Merge pull request 'feat(vcs): add CommitID to ReviewRequest (#115)' (#118) from review-bot-issue-115 into feature/github-support

Reviewed-on: #118
Reviewed-by: security-review-bot <10+security-review-bot@noreply.gitea.weiker.me>
Reviewed-by: Aaron Weiker <aaron@weiker.org>

.gitea/actions/review/action.yml

@@ -1,43 +1,17 @@
-# This composite action supports both Gitea Actions and GitHub Actions runners.
-# It detects the VCS host type by checking whether github.api_url is set
-# (present on GitHub.com and GHES runners, absent on Gitea runners) and uses
-# the appropriate releases API for version resolution and binary download
-# (REST API on GitHub, direct URLs on Gitea).
-#
-# Security notes:
-# - On GitHub/GHES (VCS_TYPE=github), inputs.vcs-url is IGNORED to prevent
-#   token exfiltration. API calls use github.api_url; downloads use
-#   github.server_url. Tokens are never sent to user-supplied URLs.
-# - On Gitea (VCS_TYPE=gitea), inputs.vcs-url is validated (https scheme,
-#   no whitespace/newlines, and DNS resolution to a public IP) before use.
-#   Python3 resolves the hostname and rejects RFC1918, RFC6598 (carrier-grade
-#   NAT), loopback, link-local, and other reserved addresses to prevent SSRF attacks.
-#   The installed review-bot binary additionally uses a safe HTTP transport
-#   (DialContext-level IP check) for all Gitea API calls at runtime.
-#   The binary also exposes a `validate-url` subcommand for use in any future
-#   shell steps that need to validate a URL before passing it to curl.
-# - action-repo is validated against owner/repo pattern.
-# - Tokens are passed via masked environment variables, not step outputs.
-#
+# This composite action is designed for Gitea Actions runners.
+# Gitea Actions supports GitHub Actions syntax including $GITHUB_OUTPUT,
+# actions/cache, and actions/checkout.
 # Requirements: python3, sha256sum, curl (all present on ubuntu-* runners).
 name: 'AI Code Review'
 description: 'Run AI-powered code review on a pull request using review-bot'
 
 inputs:
-  vcs-url:
-    description: 'VCS server URL (only used on Gitea runners; ignored on GitHub/GHES). Defaults to server_url.'
+  gitea-url:
+    description: 'Gitea instance URL (defaults to server_url)'
     required: false
     default: ''
   repo:
-    description: 'Repository to review (owner/name, defaults to current)'
-    required: false
-    default: ''
-  action-repo:
-    description: 'Repository hosting review-bot releases (owner/name). Defaults to github.action_repository or rodin/review-bot.'
-    required: false
-    default: ''
-  action-repo-token:
-    description: 'Token for downloading release assets from action-repo (defaults to github.token on GitHub, reviewer-token on Gitea). Required for private repos.'
+    description: 'Repository (owner/name, defaults to current)'
     required: false
     default: ''
   pr-number:
@@ -45,7 +19,7 @@ inputs:
     required: false
     default: ''
   reviewer-token:
-    description: 'Token for posting the review'
+    description: 'Gitea token for posting the review'
     required: true
   reviewer-name:
     description: 'Display name for the reviewer'
@@ -138,325 +112,45 @@ runs:
       id: version
       shell: bash
       run: |
-        set -euo pipefail
-
-        # --- Input Validation ---
-
-        # Determine the repo hosting review-bot releases (not the repo being reviewed)
-        ACTION_REPO="${{ inputs.action-repo }}"
-        if [ -z "$ACTION_REPO" ]; then
-          # github.action_repository is the repo containing the running action
-          ACTION_REPO="${{ github.action_repository }}"
-        fi
-        if [ -z "$ACTION_REPO" ]; then
-          # Final fallback for Gitea (which may not set action_repository)
-          ACTION_REPO="rodin/review-bot"
-          echo "::notice::action-repo not specified and github.action_repository is empty; falling back to rodin/review-bot"
-        fi
-
-        # Validate ACTION_REPO matches owner/repo pattern (prevent path traversal)
-        if ! printf '%s' "$ACTION_REPO" | grep -qE '^[a-zA-Z0-9._-]+/[a-zA-Z0-9._-]+$'; then
-          echo "Error: action-repo '${ACTION_REPO}' does not match expected owner/repo format" >&2
-          exit 1
-        fi
-
-        # Detect VCS host type using github.api_url context.
-        # github.api_url is set on GitHub.com (https://api.github.com) and GHES
-        # (https://<host>/api/v3). It is empty/unset on Gitea Actions runners.
-        GITHUB_API_URL="${{ github.api_url }}"
-        if [ -n "$GITHUB_API_URL" ]; then
-          VCS_TYPE="github"
-        else
-          VCS_TYPE="gitea"
-        fi
-
-        # Determine SERVER_URL based on VCS type.
-        # SECURITY: On GitHub/GHES, ALWAYS use github.server_url — never trust
-        # inputs.vcs-url to prevent token exfiltration to attacker-controlled hosts.
-        if [ "$VCS_TYPE" = "github" ]; then
-          SERVER_URL="${{ github.server_url }}"
-          if [ -n "${{ inputs.vcs-url }}" ]; then
-            echo "::warning::inputs.vcs-url is ignored on GitHub/GHES runners (VCS_TYPE=github). Using github.server_url instead."
-          fi
-        else
-          SERVER_URL="${{ inputs.vcs-url || github.server_url }}"
-        fi
-        # Strip trailing slash if present
-        SERVER_URL="${SERVER_URL%/}"
-
-        # Validate SERVER_URL for Gitea path: must be https, no whitespace/newlines.
-        # The [^[:space:]] class already rejects newlines, so no separate newline check needed.
-        if [ "$VCS_TYPE" = "gitea" ]; then
-          if ! printf '%s' "$SERVER_URL" | grep -qE '^https://[^[:space:]]+$'; then
-            echo "Error: SERVER_URL '${SERVER_URL}' must be an https:// URL with no whitespace" >&2
-            exit 1
-          fi
-
-          # Additional IP-level SSRF defense: resolve the hostname and reject
-          # requests to RFC1918, RFC6598 (carrier-grade NAT), loopback, link-local,
-          # and other reserved addresses.
-          # python3 is required on ubuntu-* runners (see requirements comment above).
-          # Use printf to write the script to a temp file so the python lines are valid
-          # YAML (each indented line becomes a printf argument — no unindented code).
-          # SERVER_URL is passed via CHECK_URL env var, never interpolated into python code.
-          printf '%s\n' \
-            'import socket,ipaddress,sys,os' \
-            'from urllib.parse import urlparse' \
-            'u=os.environ["CHECK_URL"]; parsed=urlparse(u)' \
-            'if parsed.username or parsed.password:' \
-            '  print("Error: URL contains user-info — not allowed",file=sys.stderr); sys.exit(2)' \
-            'h=parsed.hostname' \
-            '(print("Error: no hostname",file=sys.stderr) or sys.exit(2)) if not h else None' \
-            'try: rs=socket.getaddrinfo(h,None)' \
-            'except socket.gaierror as e: print(f"DNS error: {e}",file=sys.stderr); sys.exit(1)' \
-            'if not rs: print("Error: no addresses",file=sys.stderr); sys.exit(1)' \
-            'for _,_,_,_,(a,*_) in rs:' \
-            '  ip=ipaddress.ip_address(a)' \
-            '  if isinstance(ip,ipaddress.IPv6Address) and ip.ipv4_mapped: ip=ip.ipv4_mapped' \
-            '  cgn=ipaddress.ip_network("100.64.0.0/10")' \
-            '  if ip.is_private or ip.is_loopback or ip.is_link_local or ip.is_multicast or ip.is_reserved or ip in cgn:' \
-            '    print(f"blocked: {a}",file=sys.stderr); sys.exit(1)' \
-            > /tmp/_ssrf_check.py
-          CHECK_URL="${SERVER_URL}" python3 /tmp/_ssrf_check.py || {
-            echo "Error: SERVER_URL '${SERVER_URL}' resolves to a private/reserved IP address" >&2
-            exit 1
-          }
-        fi
-
-        # Determine auth token for release API requests
-        ACTION_TOKEN="${{ inputs.action-repo-token }}"
-        if [ -z "$ACTION_TOKEN" ]; then
-          if [ "$VCS_TYPE" = "github" ]; then
-            ACTION_TOKEN="${{ github.token }}"
-          else
-            ACTION_TOKEN="${{ inputs.reviewer-token }}"
-          fi
-        fi
-
-        # Validate token contains no control characters (defense-in-depth against header injection)
-        if [ -n "$ACTION_TOKEN" ]; then
-          if printf '%s' "$ACTION_TOKEN" | LC_ALL=C grep -q '[^[:print:]]'; then
-            echo "Error: ACTION_TOKEN contains control characters" >&2
-            exit 1
-          fi
-        fi
-
+        GITEA_URL="${{ inputs.gitea-url || github.server_url }}"
+        REPO="${{ inputs.repo || 'rodin/review-bot' }}"
         if [ "${{ inputs.version }}" = "latest" ]; then
-          if [ "$VCS_TYPE" = "github" ]; then
-            # SECURITY: Use github.api_url which is a trusted platform-provided value.
-            # Never construct API URLs from user-supplied inputs on GitHub.
-            API_URL="${GITHUB_API_URL}/repos/${ACTION_REPO}/releases?per_page=1"
-          else
-            # Gitea API — SERVER_URL was validated above
-            API_URL="${SERVER_URL}/api/v1/repos/${ACTION_REPO}/releases?limit=1"
-          fi
-
-          # Fetch latest version with inline auth header (no intermediate variable)
-          if [ -n "$ACTION_TOKEN" ]; then
-            if [ "$VCS_TYPE" = "github" ]; then
-              VERSION=$(curl -sSf --connect-timeout 10 --max-time 30 \
-                -H "Authorization: Bearer ${ACTION_TOKEN}" "$API_URL" \
-                | python3 -c "import sys, json; releases = json.load(sys.stdin); print(releases[0]['tag_name'] if releases else '')")
-            else
-              VERSION=$(curl -sSf --connect-timeout 10 --max-time 30 \
-                -H "Authorization: token ${ACTION_TOKEN}" "$API_URL" \
-                | python3 -c "import sys, json; releases = json.load(sys.stdin); print(releases[0]['tag_name'] if releases else '')")
-            fi
-          else
-            VERSION=$(curl -sSf --connect-timeout 10 --max-time 30 "$API_URL" \
-              | python3 -c "import sys, json; releases = json.load(sys.stdin); print(releases[0]['tag_name'] if releases else '')")
-          fi
-
+          VERSION=$(curl -sSf "${GITEA_URL}/api/v1/repos/${REPO}/releases?limit=1" \
+            | python3 -c "import sys, json; releases = json.load(sys.stdin); print(releases[0]['tag_name'] if releases else '')")
           if [ -z "$VERSION" ]; then
-            echo "Failed to determine latest version from ${API_URL}" >&2
+            echo "Failed to determine latest version" >&2
             exit 1
           fi
         else
           VERSION="${{ inputs.version }}"
         fi
-
-        # Validate VERSION: no slashes or whitespace (prevent path traversal).
-        # [:space:] includes newlines and carriage returns in POSIX.
-        if printf '%s' "$VERSION" | grep -qE '[/[:space:]]'; then
-          echo "Error: VERSION '${VERSION}' contains invalid characters (newline, slash, or whitespace)" >&2
-          exit 1
-        fi
-
-        # Detect OS and architecture for platform-specific binary download
-        OS_RAW=$(uname -s | tr '[:upper:]' '[:lower:]')
-        case "$OS_RAW" in
-          linux)  OS="linux" ;;
-          darwin) OS="darwin" ;;
-          *)
-            echo "Error: unsupported OS: $(uname -s)" >&2
-            exit 1
-            ;;
-        esac
-
-        RAW_ARCH=$(uname -m)
-        case "$RAW_ARCH" in
-          x86_64)           ARCH="amd64" ;;
-          aarch64 | arm64)  ARCH="arm64" ;;
-          *)
-            echo "Error: unsupported architecture: $RAW_ARCH" >&2
-            exit 1
-            ;;
-        esac
-
         echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
-        echo "os=${OS}" >> "$GITHUB_OUTPUT"
-        echo "arch=${ARCH}" >> "$GITHUB_OUTPUT"
-        echo "action_repo=${ACTION_REPO}" >> "$GITHUB_OUTPUT"
-        echo "server_url=${SERVER_URL}" >> "$GITHUB_OUTPUT"
-        echo "vcs_type=${VCS_TYPE}" >> "$GITHUB_OUTPUT"
-
-        # SECURITY: Pass token via masked environment variable instead of step output.
-        # Step outputs can leak in debug logs; GITHUB_ENV with masking is safer.
-        if [ -n "$ACTION_TOKEN" ]; then
-          echo "::add-mask::${ACTION_TOKEN}"
-          echo "ACTION_TOKEN=${ACTION_TOKEN}" >> "$GITHUB_ENV"
-        fi
 
     - name: Cache review-bot binary
       id: cache
       uses: actions/cache@v4
       with:
         path: ${{ runner.temp }}/review-bot
-        key: review-bot-${{ steps.version.outputs.os }}-${{ steps.version.outputs.arch }}-${{ steps.version.outputs.version }}
+        key: review-bot-linux-amd64-${{ steps.version.outputs.version }}
 
     - name: Install review-bot
       if: steps.cache.outputs.cache-hit != 'true'
       shell: bash
       run: |
-        set -euo pipefail
-
-        SERVER_URL="${{ steps.version.outputs.server_url }}"
-        ACTION_REPO="${{ steps.version.outputs.action_repo }}"
+        GITEA_URL="${{ inputs.gitea-url || github.server_url }}"
+        REPO="${{ inputs.repo || 'rodin/review-bot' }}"
         VERSION="${{ steps.version.outputs.version }}"
-        VCS_TYPE="${{ steps.version.outputs.vcs_type }}"
-        OS="${{ steps.version.outputs.os }}"
-        ARCH="${{ steps.version.outputs.arch }}"
-        # Read token from masked environment variable (set in Determine version step)
-        # Falls back to empty if not set (public repos don't need auth)
-        ACTION_TOKEN="${ACTION_TOKEN:-}"
-        BINARY="review-bot-${OS}-${ARCH}"
+        BINARY="review-bot-linux-amd64"
 
-        # SECURITY: Re-validate SERVER_URL at the start of this step to mitigate DNS
-        # rebinding attacks. A DNS TTL expiry between "Determine version" and here
-        # could allow an attacker to change the resolved IP to a private/reserved
-        # address, causing curl to send ACTION_TOKEN to an internal host.
-        # Only needed on Gitea path (VCS_TYPE=gitea); GitHub/GHES uses platform-controlled URLs.
-        if [ "$VCS_TYPE" = "gitea" ]; then
-          printf '%s\n' \
-            'import socket,ipaddress,sys,os' \
-            'from urllib.parse import urlparse' \
-            'u=os.environ["CHECK_URL"]; parsed=urlparse(u)' \
-            'if parsed.username or parsed.password:' \
-            '  print("Error: URL contains user-info — not allowed",file=sys.stderr); sys.exit(2)' \
-            'h=parsed.hostname' \
-            '(print("Error: no hostname",file=sys.stderr) or sys.exit(2)) if not h else None' \
-            'try: rs=socket.getaddrinfo(h,None)' \
-            'except socket.gaierror as e: print(f"DNS error: {e}",file=sys.stderr); sys.exit(1)' \
-            'if not rs: print("Error: no addresses",file=sys.stderr); sys.exit(1)' \
-            'for _,_,_,_,(a,*_) in rs:' \
-            '  ip=ipaddress.ip_address(a)' \
-            '  if isinstance(ip,ipaddress.IPv6Address) and ip.ipv4_mapped: ip=ip.ipv4_mapped' \
-            '  cgn=ipaddress.ip_network("100.64.0.0/10")' \
-            '  if ip.is_private or ip.is_loopback or ip.is_link_local or ip.is_multicast or ip.is_reserved or ip in cgn:' \
-            '    print(f"blocked: {a}",file=sys.stderr); sys.exit(1)' \
-              > /tmp/_ssrf_check_install.py
-          CHECK_URL="${SERVER_URL}" python3 /tmp/_ssrf_check_install.py || {
-            echo "Error: SERVER_URL '${SERVER_URL}' resolves to a private/reserved IP address" >&2
-            exit 1
-          }
-        fi
-
-        if [ "$VCS_TYPE" = "github" ]; then
-          # GitHub/GHES: Use REST API for release asset downloads.
-          # Web release URLs ({server}/.../releases/download/{tag}/{asset}) redirect
-          # to S3 and don't reliably support Authorization headers for private repos.
-          # The REST API endpoint with Accept: application/octet-stream is required.
-          # GITHUB_API_URL: trusted platform value, same as detected in "Determine version" step.
-          GITHUB_API_URL="${{ github.api_url }}"
-
-          if [ -n "$ACTION_TOKEN" ]; then
-            RELEASE_JSON=$(curl -sSf --connect-timeout 10 --max-time 30 \
-              -H "Authorization: Bearer ${ACTION_TOKEN}" \
-              "${GITHUB_API_URL}/repos/${ACTION_REPO}/releases/tags/${VERSION}")
-          else
-            RELEASE_JSON=$(curl -sSf --connect-timeout 10 --max-time 30 \
-              "${GITHUB_API_URL}/repos/${ACTION_REPO}/releases/tags/${VERSION}")
-          fi
-
-          # Extract asset IDs for binary and checksums
-          BINARY_ASSET_ID=$(printf '%s' "$RELEASE_JSON" | python3 -c "import sys, json; assets = json.load(sys.stdin).get('assets', []); matches = [a['id'] for a in assets if a['name'] == '${BINARY}']; print(matches[0] if matches else '')")
-          if [ -z "$BINARY_ASSET_ID" ]; then
-            echo "Error: could not find asset '${BINARY}' in release ${VERSION}" >&2
-            exit 1
-          fi
-
-          CHECKSUMS_ASSET_ID=$(printf '%s' "$RELEASE_JSON" | python3 -c "import sys, json; assets = json.load(sys.stdin).get('assets', []); matches = [a['id'] for a in assets if a['name'] == 'checksums.txt']; print(matches[0] if matches else '')")
-          if [ -z "$CHECKSUMS_ASSET_ID" ]; then
-            echo "Error: could not find asset 'checksums.txt' in release ${VERSION}" >&2
-            exit 1
-          fi
-
-          # Download assets via REST API with Accept: application/octet-stream
-          if [ -n "$ACTION_TOKEN" ]; then
-            curl -sSfL --connect-timeout 10 --max-time 120 \
-              -H "Authorization: Bearer ${ACTION_TOKEN}" \
-              -H "Accept: application/octet-stream" \
-              "${GITHUB_API_URL}/repos/${ACTION_REPO}/releases/assets/${BINARY_ASSET_ID}" \
-              -o "${{ runner.temp }}/review-bot"
-            curl -sSfL --connect-timeout 10 --max-time 30 \
-              -H "Authorization: Bearer ${ACTION_TOKEN}" \
-              -H "Accept: application/octet-stream" \
-              "${GITHUB_API_URL}/repos/${ACTION_REPO}/releases/assets/${CHECKSUMS_ASSET_ID}" \
-              -o "${{ runner.temp }}/checksums.txt"
-          else
-            curl -sSfL --connect-timeout 10 --max-time 120 \
-              -H "Accept: application/octet-stream" \
-              "${GITHUB_API_URL}/repos/${ACTION_REPO}/releases/assets/${BINARY_ASSET_ID}" \
-              -o "${{ runner.temp }}/review-bot"
-            curl -sSfL --connect-timeout 10 --max-time 30 \
-              -H "Accept: application/octet-stream" \
-              "${GITHUB_API_URL}/repos/${ACTION_REPO}/releases/assets/${CHECKSUMS_ASSET_ID}" \
-              -o "${{ runner.temp }}/checksums.txt"
-          fi
-        else
-          # Gitea: Direct download via web release URLs (Gitea serves assets
-          # directly without redirects — no -L needed).
-          # SECURITY: Omitting -L prevents forwarding Authorization header to
-          # unexpected hosts if Gitea ever introduces CDN redirects.
-          DOWNLOAD_URL="${SERVER_URL}/${ACTION_REPO}/releases/download/${VERSION}"
-
-          if [ -n "$ACTION_TOKEN" ]; then
-            curl -sSf --connect-timeout 10 --max-time 120 \
-              -H "Authorization: token ${ACTION_TOKEN}" \
-              "${DOWNLOAD_URL}/${BINARY}" -o "${{ runner.temp }}/review-bot"
-            curl -sSf --connect-timeout 10 --max-time 30 \
-              -H "Authorization: token ${ACTION_TOKEN}" \
-              "${DOWNLOAD_URL}/checksums.txt" -o "${{ runner.temp }}/checksums.txt"
-          else
-            curl -sSf --connect-timeout 10 --max-time 120 \
-              "${DOWNLOAD_URL}/${BINARY}" -o "${{ runner.temp }}/review-bot"
-            curl -sSf --connect-timeout 10 --max-time 30 \
-              "${DOWNLOAD_URL}/checksums.txt" -o "${{ runner.temp }}/checksums.txt"
-          fi
-        fi
+        curl -sSfL "${GITEA_URL}/${REPO}/releases/download/${VERSION}/${BINARY}" \
+          -o "${{ runner.temp }}/review-bot"
+        curl -sSfL "${GITEA_URL}/${REPO}/releases/download/${VERSION}/checksums.txt" \
+          -o "${{ runner.temp }}/checksums.txt"
 
         # Verify SHA-256 checksum
-        # NOTE: This verifies integrity (download wasn't corrupted) but not
-        # authenticity — both binary and checksums come from the same server.
-        # For stronger guarantees, consider GPG signature verification.
         cd "${{ runner.temp }}"
-        EXPECTED=$(grep -E "^[0-9a-f]+[[:space:]]+\*?${BINARY}$" checksums.txt | awk '{print $1}')
-        # sha256sum (GNU) is not available on macOS; use shasum -a 256 on darwin.
-        if [ "${OS}" = "darwin" ]; then
-          ACTUAL=$(shasum -a 256 review-bot | awk '{print $1}')
-        else
-          ACTUAL=$(sha256sum review-bot | awk '{print $1}')
-        fi
+        EXPECTED=$(grep "${BINARY}" checksums.txt | awk '{print $1}')
+        ACTUAL=$(sha256sum review-bot | awk '{print $1}')
 
         if [ -z "$EXPECTED" ]; then
           echo "Error: no checksum found for ${BINARY}" >&2
@@ -470,13 +164,12 @@ runs:
         fi
 
         chmod +x "${{ runner.temp }}/review-bot"
-        echo "Installed review-bot-${OS}-${ARCH} ${VERSION} (checksum verified)"
+        echo "Installed review-bot ${VERSION} (checksum verified)"
 
     - name: Run review
       shell: bash
       env:
-        VCS_URL: ${{ steps.version.outputs.server_url }}
-        VCS_TYPE: ${{ steps.version.outputs.vcs_type }}
+        GITEA_URL: ${{ inputs.gitea-url || github.server_url }}
         GITEA_REPO: ${{ inputs.repo || github.repository }}
         PR_NUMBER: ${{ inputs.pr-number || github.event.pull_request.number }}
         REVIEWER_TOKEN: ${{ inputs.reviewer-token }}

.gitea/workflows/ci.yml

@@ -49,7 +49,7 @@ jobs:
       - run: go build -o review-bot ./cmd/review-bot
       - name: Run ${{ matrix.name }} review
         env:
-          VCS_URL: ${{ github.server_url }}
+          GITEA_URL: ${{ github.server_url }}
           GITEA_REPO: ${{ github.repository }}
           PR_NUMBER: ${{ github.event.pull_request.number }}
           REVIEWER_TOKEN: ${{ secrets[matrix.token_secret] }}

.github/actions/review/action.yml

@@ -0,0 +1,200 @@
+# This composite action is designed for Gitea Actions runners.
+# Gitea Actions supports GitHub Actions syntax including $GITHUB_OUTPUT,
+# actions/cache, and actions/checkout.
+# Requirements: python3, sha256sum, curl (all present on ubuntu-* runners).
+name: 'AI Code Review'
+description: 'Run AI-powered code review on a pull request using review-bot'
+
+inputs:
+  gitea-url:
+    description: 'Gitea instance URL (defaults to server_url)'
+    required: false
+    default: ''
+  repo:
+    description: 'Repository (owner/name, defaults to current)'
+    required: false
+    default: ''
+  pr-number:
+    description: 'Pull request number (defaults to current PR)'
+    required: false
+    default: ''
+  reviewer-token:
+    description: 'Gitea token for posting the review'
+    required: true
+  reviewer-name:
+    description: 'Display name for the reviewer'
+    required: false
+    default: ''
+  llm-base-url:
+    description: 'OpenAI-compatible LLM API base URL (not required for aicore provider)'
+    required: false
+    default: ''
+  llm-api-key:
+    description: 'LLM API key (not required for aicore provider)'
+    required: false
+    default: ''
+  llm-model:
+    description: 'LLM model name'
+    required: true
+  llm-provider:
+    description: 'LLM API provider: openai, anthropic, or aicore (default openai)'
+    required: false
+    default: 'openai'
+  aicore-client-id:
+    description: 'SAP AI Core client ID (required for aicore provider)'
+    required: false
+    default: ''
+  aicore-client-secret:
+    description: 'SAP AI Core client secret (required for aicore provider)'
+    required: false
+    default: ''
+  aicore-auth-url:
+    description: 'SAP AI Core authentication URL (required for aicore provider)'
+    required: false
+    default: ''
+  aicore-api-url:
+    description: 'SAP AI Core API URL (required for aicore provider)'
+    required: false
+    default: ''
+  aicore-resource-group:
+    description: 'SAP AI Core resource group (default: default)'
+    required: false
+    default: 'default'
+  conventions-file:
+    description: 'Path to conventions file in the repo (e.g. CLAUDE.md)'
+    required: false
+    default: ''
+  patterns-repo:
+    description: 'Comma-separated repos with language patterns (e.g. rodin/elixir-patterns,rodin/phoenix-conventions)'
+    required: false
+    default: ''
+  patterns-files:
+    description: 'Comma-separated file paths or directories to fetch from patterns repos'
+    required: false
+    default: 'README.md'
+  temperature:
+    description: 'LLM temperature (0 = server default)'
+    required: false
+    default: '0'
+  timeout:
+    description: 'LLM request timeout in seconds (default 300)'
+    required: false
+    default: '300'
+  version:
+    description: 'review-bot version to install (e.g. v0.1.0, defaults to latest)'
+    required: false
+    default: 'latest'
+  dry-run:
+    description: 'Print review to stdout instead of posting'
+    required: false
+    default: 'false'
+  update-existing:
+    description: 'Delete previous review from same bot after posting new one. Accepts: true/1/yes or false/0/no (default true)'
+    required: false
+    default: 'true'
+  system-prompt-file:
+    description: 'Local file with additional system prompt instructions (e.g. security review focus)'
+    required: false
+    default: ''
+  persona:
+    description: 'Built-in persona name (security, architect, docs)'
+    required: false
+    default: ''
+  persona-file:
+    description: 'Path to custom persona JSON file'
+    required: false
+    default: ''
+
+runs:
+  using: 'composite'
+  steps:
+    - name: Determine version
+      id: version
+      shell: bash
+      run: |
+        GITEA_URL="${{ inputs.gitea-url || github.server_url }}"
+        REPO="${{ inputs.repo || 'rodin/review-bot' }}"
+        if [ "${{ inputs.version }}" = "latest" ]; then
+          VERSION=$(curl -sSf "${GITEA_URL}/api/v1/repos/${REPO}/releases?limit=1" \
+            | python3 -c "import sys, json; releases = json.load(sys.stdin); print(releases[0]['tag_name'] if releases else '')")
+          if [ -z "$VERSION" ]; then
+            echo "Failed to determine latest version" >&2
+            exit 1
+          fi
+        else
+          VERSION="${{ inputs.version }}"
+        fi
+        echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
+
+    - name: Cache review-bot binary
+      id: cache
+      uses: actions/cache@v4
+      with:
+        path: ${{ runner.temp }}/review-bot
+        key: review-bot-linux-amd64-${{ steps.version.outputs.version }}
+
+    - name: Install review-bot
+      if: steps.cache.outputs.cache-hit != 'true'
+      shell: bash
+      run: |
+        GITEA_URL="${{ inputs.gitea-url || github.server_url }}"
+        REPO="${{ inputs.repo || 'rodin/review-bot' }}"
+        VERSION="${{ steps.version.outputs.version }}"
+        BINARY="review-bot-linux-amd64"
+
+        curl -sSfL "${GITEA_URL}/${REPO}/releases/download/${VERSION}/${BINARY}" \
+          -o "${{ runner.temp }}/review-bot"
+        curl -sSfL "${GITEA_URL}/${REPO}/releases/download/${VERSION}/checksums.txt" \
+          -o "${{ runner.temp }}/checksums.txt"
+
+        # Verify SHA-256 checksum
+        cd "${{ runner.temp }}"
+        EXPECTED=$(grep "${BINARY}" checksums.txt | awk '{print $1}')
+        ACTUAL=$(sha256sum review-bot | awk '{print $1}')
+
+        if [ -z "$EXPECTED" ]; then
+          echo "Error: no checksum found for ${BINARY}" >&2
+          exit 1
+        fi
+        if [ "$EXPECTED" != "$ACTUAL" ]; then
+          echo "Error: checksum mismatch!" >&2
+          echo "  Expected: $EXPECTED" >&2
+          echo "  Actual:   $ACTUAL" >&2
+          exit 1
+        fi
+
+        chmod +x "${{ runner.temp }}/review-bot"
+        echo "Installed review-bot ${VERSION} (checksum verified)"
+
+    - name: Run review
+      shell: bash
+      env:
+        GITHUB_SERVER_URL: ${{ inputs.gitea-url || github.server_url }}
+        GITHUB_REPOSITORY: ${{ inputs.repo || github.repository }}
+        PR_NUMBER: ${{ inputs.pr-number || github.event.pull_request.number }}
+        REVIEWER_TOKEN: ${{ inputs.reviewer-token }}
+        REVIEWER_NAME: ${{ inputs.reviewer-name }}
+        LLM_BASE_URL: ${{ inputs.llm-base-url }}
+        LLM_API_KEY: ${{ inputs.llm-api-key }}
+        LLM_MODEL: ${{ inputs.llm-model }}
+        CONVENTIONS_FILE: ${{ inputs.conventions-file }}
+        PATTERNS_REPO: ${{ inputs.patterns-repo }}
+        PATTERNS_FILES: ${{ inputs.patterns-files }}
+        LLM_TEMPERATURE: ${{ inputs.temperature }}
+        LLM_TIMEOUT: ${{ inputs.timeout }}
+        LLM_PROVIDER: ${{ inputs.llm-provider }}
+        UPDATE_EXISTING: ${{ inputs.update-existing }}
+        SYSTEM_PROMPT_FILE: ${{ inputs.system-prompt-file }}
+        PERSONA: ${{ inputs.persona }}
+        PERSONA_FILE: ${{ inputs.persona-file }}
+        AICORE_CLIENT_ID: ${{ inputs.aicore-client-id }}
+        AICORE_CLIENT_SECRET: ${{ inputs.aicore-client-secret }}
+        AICORE_AUTH_URL: ${{ inputs.aicore-auth-url }}
+        AICORE_API_URL: ${{ inputs.aicore-api-url }}
+        AICORE_RESOURCE_GROUP: ${{ inputs.aicore-resource-group }}
+      run: |
+        ARGS=""
+        if [ "${{ inputs.dry-run }}" = "true" ]; then
+          ARGS="--dry-run"
+        fi
+        ${{ runner.temp }}/review-bot $ARGS

.github/workflows/ci.yml

@@ -0,0 +1,69 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    types: [opened, synchronize]
+
+jobs:
+  test:
+    runs-on: ubuntu-24.04
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: '1.26'
+      - run: go test ./...
+      - run: go vet ./...
+      - run: go build -o review-bot ./cmd/review-bot
+
+  # Self-review using native SAP AI Core provider
+  # Models must match SAP AI Core deployments
+  # Available models: gpt-5, anthropic--claude-4.6-sonnet, anthropic--claude-4.6-opus
+  # Removed gpt-4.1, gpt-5-mini, gpt-4.1-mini - not deployed on AI Core
+  review:
+    runs-on: ubuntu-24.04
+    if: github.event_name == 'pull_request'
+    needs: test
+    strategy:
+      matrix:
+        include:
+          - name: sonnet
+            token_secret: SONNET_REVIEW_TOKEN
+            model: anthropic--claude-4.6-sonnet
+          - name: gpt
+            token_secret: GPT_REVIEW_TOKEN
+            model: gpt-5
+          - name: security
+            token_secret: SECURITY_REVIEW_TOKEN
+            model: gpt-5
+            patterns_repo: rodin/security-patterns
+            patterns_files: "."
+            system_prompt_file: SECURITY_REVIEW.md
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: '1.26'
+      - run: go build -o review-bot ./cmd/review-bot
+      - name: Run ${{ matrix.name }} review
+        env:
+          GITHUB_SERVER_URL: ${{ github.server_url }}
+          GITHUB_REPOSITORY: ${{ github.repository }}
+          PR_NUMBER: ${{ github.event.pull_request.number }}
+          REVIEWER_TOKEN: ${{ secrets[matrix.token_secret] }}
+          REVIEWER_NAME: ${{ matrix.name }}
+          LLM_PROVIDER: aicore
+          LLM_MODEL: ${{ matrix.model }}
+          AICORE_CLIENT_ID: ${{ secrets.AICORE_CLIENT_ID }}
+          AICORE_CLIENT_SECRET: ${{ secrets.AICORE_CLIENT_SECRET }}
+          AICORE_AUTH_URL: ${{ secrets.AICORE_AUTH_URL }}
+          AICORE_API_URL: ${{ secrets.AICORE_API_URL }}
+          AICORE_RESOURCE_GROUP: ${{ secrets.AICORE_RESOURCE_GROUP }}
+          CONVENTIONS_FILE: "CONVENTIONS.md"
+          PATTERNS_REPO: ${{ matrix.patterns_repo || 'rodin/go-patterns' }}
+          PATTERNS_FILES: ${{ matrix.patterns_files || 'README.md,patterns/' }}
+          LLM_TIMEOUT: "600"
+          SYSTEM_PROMPT_FILE: ${{ matrix.system_prompt_file }}
+        run: ./review-bot

.github/workflows/pr-ready-gate.yml

@@ -0,0 +1,38 @@
+name: PR Ready Gate
+
+on:
+  pull_request:
+    types: [synchronize]
+
+jobs:
+  clear-labels:
+    runs-on: ubuntu-24.04
+    # Always run - curl commands are safe if labels don't exist
+    steps:
+      - name: Remove ready and self-reviewed labels, reassign to author
+        env:
+          GITEA_TOKEN: ${{ secrets.RODIN_TOKEN }}
+        run: |
+          PR_NUMBER=${{ github.event.pull_request.number }}
+          AUTHOR=${{ github.event.pull_request.user.login }}
+          READY_LABEL_ID=38
+          SELF_REVIEWED_LABEL_ID=37
+          
+          # Remove ready label if present
+          curl -sS -X DELETE \
+            -H "Authorization: token $GITEA_TOKEN" \
+            "https://gitea.weiker.me/api/v1/repos/${{ github.repository }}/issues/${PR_NUMBER}/labels/${READY_LABEL_ID}" || true
+          
+          # Remove self-reviewed label if present
+          curl -sS -X DELETE \
+            -H "Authorization: token $GITEA_TOKEN" \
+            "https://gitea.weiker.me/api/v1/repos/${{ github.repository }}/issues/${PR_NUMBER}/labels/${SELF_REVIEWED_LABEL_ID}" || true
+          
+          # Reassign to author
+          curl -sS -X PATCH \
+            -H "Authorization: token $GITEA_TOKEN" \
+            -H "Content-Type: application/json" \
+            -d "{\"assignees\": [\"${AUTHOR}\"]}" \
+            "https://gitea.weiker.me/api/v1/repos/${{ github.repository }}/pulls/${PR_NUMBER}"
+          
+          echo "Cleared ready/self-reviewed labels and reassigned PR #${PR_NUMBER} to ${AUTHOR}"

.github/workflows/release.yml

@@ -0,0 +1,97 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+jobs:
+  release:
+    runs-on: ubuntu-24.04
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-go@v5
+        with:
+          go-version: '1.26'
+
+      - name: Run tests
+        run: |
+          go vet ./...
+          go test ./...
+
+      - name: Build binaries
+        run: |
+          VERSION=${GITHUB_REF_NAME}
+          mkdir -p dist
+
+          GOOS=linux GOARCH=amd64 go build -ldflags "-s -w -X main.version=${VERSION}" -o dist/review-bot-linux-amd64 ./cmd/review-bot
+          GOOS=linux GOARCH=arm64 go build -ldflags "-s -w -X main.version=${VERSION}" -o dist/review-bot-linux-arm64 ./cmd/review-bot
+          GOOS=darwin GOARCH=amd64 go build -ldflags "-s -w -X main.version=${VERSION}" -o dist/review-bot-darwin-amd64 ./cmd/review-bot
+          GOOS=darwin GOARCH=arm64 go build -ldflags "-s -w -X main.version=${VERSION}" -o dist/review-bot-darwin-arm64 ./cmd/review-bot
+
+          cd dist && sha256sum * > checksums.txt
+
+      - name: Create release and upload assets
+        env:
+          GITEA_TOKEN: ${{ secrets.RELEASE_TOKEN }}
+        run: |
+          VERSION=${GITHUB_REF_NAME}
+          GITEA_URL="${{ github.server_url }}"
+          REPO="${{ github.repository }}"
+
+          # Create release (or find existing one for this tag)
+          HTTP_CODE=$(curl -s -o /tmp/release_response.json -w "%{http_code}" -X POST \
+            -H "Authorization: token ${GITEA_TOKEN}" \
+            -H "Content-Type: application/json" \
+            "${GITEA_URL}/api/v1/repos/${REPO}/releases" \
+            -d "{\"tag_name\": \"${VERSION}\", \"name\": \"${VERSION}\", \"body\": \"Release ${VERSION}\", \"draft\": false, \"prerelease\": false}")
+
+          if [ "$HTTP_CODE" = "409" ]; then
+            echo "Release for ${VERSION} already exists, fetching existing..."
+            curl -sSf -o /tmp/release_response.json \
+              -H "Authorization: token ${GITEA_TOKEN}" \
+              "${GITEA_URL}/api/v1/repos/${REPO}/releases/tags/${VERSION}"
+          elif [ "$HTTP_CODE" != "201" ]; then
+            echo "Failed to create release (HTTP ${HTTP_CODE})" >&2
+            cat /tmp/release_response.json >&2
+            exit 1
+          fi
+
+          # Parse release ID (python3 available on ubuntu-24.04 runners)
+          RELEASE_ID=$(python3 -c "import json; print(json.load(open('/tmp/release_response.json'))['id'])")
+
+          if [ -z "$RELEASE_ID" ]; then
+            echo "Failed to parse release ID" >&2
+            cat /tmp/release_response.json >&2
+            exit 1
+          fi
+
+          echo "Release ID: ${RELEASE_ID}"
+
+          # Upload each asset (idempotent: delete existing asset with same name first)
+          for file in dist/*; do
+            filename=$(basename "$file")
+            echo "Uploading ${filename}..."
+
+            # Check if asset already exists and delete it
+            EXISTING_ID=$(export ASSET_NAME="${filename}"; curl -sS \
+              -H "Authorization: token ${GITEA_TOKEN}" \
+              "${GITEA_URL}/api/v1/repos/${REPO}/releases/${RELEASE_ID}/assets" \
+              | python3 -c "import json,sys,os; name=os.environ['ASSET_NAME']; assets=json.load(sys.stdin); print(next((str(a['id']) for a in assets if a['name']==name),''))" 2>/dev/null)
+
+            if [ -n "$EXISTING_ID" ]; then
+              echo "  Asset ${filename} already exists (id=${EXISTING_ID}), deleting..."
+              curl -sSf -X DELETE \
+                -H "Authorization: token ${GITEA_TOKEN}" \
+                "${GITEA_URL}/api/v1/repos/${REPO}/releases/${RELEASE_ID}/assets/${EXISTING_ID}"
+            fi
+
+            curl -sSf -X POST \
+              -H "Authorization: token ${GITEA_TOKEN}" \
+              -H "Content-Type: application/octet-stream" \
+              "${GITEA_URL}/api/v1/repos/${REPO}/releases/${RELEASE_ID}/assets?name=$(printf '%s' "${filename}" | jq -sRr @uri)" \
+              --data-binary "@${file}"
+          done
+
+          echo "Release ${VERSION} created with assets"

CONVENTIONS.md

@@ -9,7 +9,7 @@
 
 | Package | Use Case | Scope |
 |---------|----------|-------|
-| `github.com/goccy/go-yaml` | YAML parsing and AST inspection (subpkgs: `ast`, `parser`) | production |
+| `gopkg.in/yaml.v3` | YAML parsing (persona files, config) | production |
 | `github.com/google/go-cmp` | Test comparisons (`cmp.Diff`) | test only |
 
 **Any import not in this table or the Go standard library is forbidden.**

PLAN-125.md

@@ -1,175 +0,0 @@
-# Plan: Issue #125 — Rename GITEA_URL → VCS_URL
-
-## Problem
-
-The `GITEA_URL` environment variable (and `--gitea-url` flag) implies the binary only works with Gitea.
-Now that review-bot supports both Gitea and GitHub/GHES, this name is misleading.
-Renaming to `VCS_URL` makes the binary platform-agnostic in its interface.
-
-## Constraints
-
-- Must not break existing users who already use `GITEA_URL` — need a fallback
-- The CLI flag `--gitea-url` should also be updated to `--vcs-url` for consistency
-- `INTEGRATION_GITEA_URL` in integration tests is a test-only env var, not the binary's interface; but should be updated for clarity
-- The action YAML uses `GITEA_URL` as an internal shell variable in bash scripts — distinct from the env var passed to the binary
-- All changes must compile and pass existing tests
-
-## Files Affected
-
-### Binary / Go source
-| File | Change |
-|------|--------|
-| `cmd/review-bot/main.go` | Rename `--gitea-url` → `--vcs-url`, add `VCS_URL` as primary, keep `GITEA_URL` fallback |
-| `cmd/review-bot/integration_test.go` | Rename `INTEGRATION_GITEA_URL` → `INTEGRATION_VCS_URL` (test-only, no external compat concern) |
-| `integration_test.go` | Same — rename `INTEGRATION_GITEA_URL` → `INTEGRATION_VCS_URL` |
-
-### Action YAML
-| File | Change |
-|------|--------|
-| `.gitea/actions/review/action.yml` | Rename input `gitea-url` → `vcs-url`; update env var passed to binary: `VCS_URL` instead of `GITEA_URL`; keep internal bash var as `GITEA_URL` (only used for release download, not passed to binary) |
-| `.gitea/workflows/ci.yml` | Rename `GITEA_URL` env var to `VCS_URL` in Run review step |
-
-### Documentation
-| File | Change |
-|------|--------|
-| `README.md` | Update CLI example, env var table entry |
-
-## Proposed Approach
-
-### 1. Backward-compatible env var lookup in main.go
-
-Replace:
-```go
-giteaURL := flag.String("gitea-url", envOrDefault("GITEA_URL", ""), "Gitea instance URL")
-```
-
-With:
-```go
-giteaURL := flag.String("vcs-url", envOrDefaultFallback("VCS_URL", "GITEA_URL", ""), "VCS server URL (e.g. https://gitea.example.com)")
-```
-
-Add a helper:
-```go
-// envOrDefaultFallback reads primary env var; if empty, falls back to deprecated env var.
-func envOrDefaultFallback(primary, deprecated, defaultVal string) string {
-    if v := os.Getenv(primary); v != "" {
-        return v
-    }
-    if v := os.Getenv(deprecated); v != "" {
-        slog.Warn("deprecated env var in use; rename to " + primary, "old", deprecated, "new", primary)
-        return v
-    }
-    return defaultVal
-}
-```
-
-**Note:** This must be called AFTER `setupLogger` conceptually, but the flag default is evaluated at flag registration time. Since `setupLogger` runs before `flag.Parse()`, the slog.Warn will print correctly at runtime. We use `log.Printf` as a fallback if this proves problematic.
-
-Actually — flag defaults are evaluated at registration (line 57), before `setupLogger`. The warning won't go through slog. Two options:
-- Use `log.Printf` for the deprecation warning (always visible)
-- Move the fallback lookup to after `flag.Parse()`, checking if the parsed value is still empty
-
-**Decision:** Move fallback to a post-parse check. This is cleaner:
-```go
-vcsURL := flag.String("vcs-url", os.Getenv("VCS_URL"), "VCS server URL")
-flag.Parse()
-// Backward compat: fall back to deprecated GITEA_URL
-if *vcsURL == "" {
-    if v := os.Getenv("GITEA_URL"); v != "" {
-        slog.Warn("GITEA_URL is deprecated; use VCS_URL instead")
-        *vcsURL = v
-    }
-}
-```
-
-This is clean, idiomatic, and the warning goes through slog correctly.
-
-### 2. Keep `--gitea-url` as deprecated alias
-
-Add a hidden flag for backward compat:
-```go
-giteaURLAlias := flag.String("gitea-url", "", "Deprecated: use --vcs-url")
-```
-
-Post-parse:
-```go
-if *vcsURL == "" && *giteaURLAlias != "" {
-    slog.Warn("--gitea-url is deprecated; use --vcs-url instead")
-    *vcsURL = *giteaURLAlias
-}
-```
-
-### 3. Internal variable rename
-
-Rename `giteaURL` local variable → `vcsURL` throughout `main.go` for consistency.
-
-### 4. Error message update
-
-```go
-fmt.Fprintf(os.Stderr, "Required: --vcs-url, --repo, --pr, --reviewer-token, --llm-model\n")
-```
-
-### 5. Action YAML changes
-
-In `.gitea/actions/review/action.yml`:
-- Input `gitea-url` → `vcs-url` (with same description, `required: false`, `default: ''`)
-- Line 172: `GITEA_URL: ${{ inputs.gitea-url || github.server_url }}` → `VCS_URL: ${{ inputs.vcs-url || github.server_url }}`
-- Lines 115, 140: internal bash vars `GITEA_URL=` are used for downloading binaries — NOT passed to the review-bot binary. Leave them as internal bash vars (they're scope-local in bash). These could be renamed to `SERVER_URL` or `BASE_URL` for local clarity, but renaming them isn't strictly required.
-
-In `.gitea/workflows/ci.yml`:
-- Line 52: `GITEA_URL: ${{ github.server_url }}` → `VCS_URL: ${{ github.server_url }}`
-
-### 6. Integration test updates
-
-`INTEGRATION_GITEA_URL` → `INTEGRATION_VCS_URL` in both test files.
-
-### 7. README
-
-- CLI example: `--gitea-url` → `--vcs-url`
-- Env var table: `GITEA_URL` → `VCS_URL`, add note about `GITEA_URL` fallback
-
-## Backward Compatibility Summary
-
-| Old | New | Fallback? |
-|-----|-----|-----------|
-| `GITEA_URL` env var | `VCS_URL` | ✅ with deprecation warning |
-| `--gitea-url` flag | `--vcs-url` | ✅ with deprecation warning |
-| `gitea-url` action input | `vcs-url` | ⚠️ No (action version bump handles this) |
-| `INTEGRATION_GITEA_URL` | `INTEGRATION_VCS_URL` | N/A (test-only) |
-
-## Error Cases
-
-- Both `VCS_URL` and `GITEA_URL` set: `VCS_URL` wins (primary takes precedence)
-- Both `--vcs-url` and `--gitea-url` provided: `--vcs-url` wins
-- Neither set: existing "missing required flags" error unchanged
-
-## Edge Cases
-
-- `os.Getenv` returns "" for unset AND set-to-empty — consistent with existing behavior
-- The `envOrDefault` helper is unchanged; we add `envOrDefaultFallback` for the one renamed var
-
-## Testing Strategy
-
-- Existing unit tests pass unchanged (they don't test env var parsing directly)
-- Integration tests updated to use new env var name
-- Manual: `GITEA_URL=https://example.com ./review-bot --repo x --pr 1 ...` should print deprecation warning and proceed
-- Manual: `VCS_URL=https://example.com ./review-bot ...` should work silently
-
-## Completion Checklist
-
-1. `VCS_URL` is read first; `GITEA_URL` is fallback with deprecation warning
-2. `--vcs-url` flag is primary; `--gitea-url` is deprecated alias with warning
-3. Error message references `--vcs-url` not `--gitea-url`
-4. `action.yml` passes `VCS_URL` (not `GITEA_URL`) to the binary
-5. `ci.yml` passes `VCS_URL` (not `GITEA_URL`) to the binary
-6. README updated in CLI example and env var table
-7. Integration tests use `INTEGRATION_VCS_URL`
-8. `go test ./...` passes
-9. `go vet ./...` passes
-10. `go build ./cmd/review-bot` succeeds
-
-## Open Questions
-
-- Should the CLI flag `--gitea-url` be completely hidden from `--help` or just deprecated with a note? The issue doesn't specify. Decision: keep it visible but add "(deprecated: use --vcs-url)" to the description.
-- Should action.yml also add `gitea-url` as a deprecated input alias? The issue says "Update the action to pass the new env var name" — no mention of backward compat for the action input. Decision: rename only, no alias (action users pin a version anyway).
-- The bash-internal `GITEA_URL` variable in action.yml scripts (used for release download, not passed to binary) — rename for clarity? Decision: yes, rename to `BASE_URL` to avoid confusion with the env var.

README.md

@@ -282,10 +282,10 @@ Rules:
 
 ```bash
 review-bot \
-  --vcs-url https://gitea.example.com \
+  --gitea-url https://gitea.example.com \
   --repo owner/name \
   --pr 42 \
-  --reviewer-token "$REVIEWER_TOKEN" \
+  --reviewer-token "$GITEA_TOKEN" \
   --reviewer-name "code-review" \
   --llm-base-url https://api.openai.com/v1 \
   --llm-api-key "$OPENAI_API_KEY" \
@@ -299,9 +299,8 @@ All flags have environment variable equivalents:
 
 | Flag | Env Var |
 |------|---------|
-| `--vcs-url` | `VCS_URL` (fallback: `GITEA_URL`) |
-| `--vcs-type` | `VCS_TYPE` (auto-detected from URL if not set; `gitea` or `github`) |
-| `--repo` | `GITEA_REPO` (also accepted: set `GITEA_REPO` for Gitea; VCS-agnostic `REPO` coming) |
+| `--gitea-url` | `GITEA_URL` |
+| `--repo` | `GITEA_REPO` |
 | `--pr` | `PR_NUMBER` |
 | `--reviewer-token` | `REVIEWER_TOKEN` |
 | `--reviewer-name` | `REVIEWER_NAME` |

TODO.md

@@ -1,88 +0,0 @@
-## Dev Loop: review-bot — 2026-05-14 20:10 UTC
-
-### Latest: ✅ STABLE STATE — REPO HEALTH COMPLETE
-- **Last action:** health check; verified tests pass, repo clean, no action needed
-- **Repository:** Clean, all merges complete, no open issues/PRs
-- **Main branch:** Up to date with origin/main
-- **Test suite:** All passing (cached)
-
----
-
-## Repository Status
-
-### ✅ Merged to main (recent):
-- issue-123 (IP-level SSRF defense) — 6 commits, main at 4440823
-- issue-125 (VCS_URL rename + deprecation) — merged
-- issue-124 (multi-arch binary support) — merged  
-- issue-120 (GitHub Actions + VCS abstraction) — merged
-- issue-121 (VCS host type detection for binary download) — merged
-
-### 🧹 Cleanup COMPLETE:
-- ✅ Removed old worktrees (issue-123, review-bot-issue-125)
-- ✅ Test suite passes (all packages)
-- ✅ No TODO/FIXME in code except expected GitHub client notes
-- ✅ No open issues or pull requests
-- ✅ Dependencies up to date
-
----
-
-## Current Feature Completeness
-
-✅ **Core Capabilities:**
-- Multi-provider LLM support (OpenAI, Anthropic, SAP AI Core)
-- Gitea PR integration with structured reviews
-- SSRF defense with IP-level validation
-- VCS abstraction (Gitea/GitHub support)
-- Multi-architecture binary support
-- GitHub Actions composite action
-
-✅ **Recent Security Work:**
-- RFC6598 CGN range detection
-- IP fallback dialing for local endpoint rejection
-- URL validation for SSRF prevention
-
-✅ **Code Quality:**
-- Comprehensive test coverage (all packages tested)
-- Consistent error handling with context propagation
-- Secure credential handling (unexported fields)
-- Concurrency-safe designs
-
----
-
-## Next Priority Actions
-
-### Phase 2: Feature Exploration (NEXT SESSION)
-- Scan code for potential improvements per REVIEW.md findings
-- Assess performance under load
-- Review REVIEW.md findings for targeted fixes
-- Consider backlog items from design docs
-
-### Phase 3: Optional Enhancements (BACKLOG)
-- Address REVIEW.md context propagation findings (if prioritized)
-- Additional LLM provider support
-- Enhanced context detection
-- Custom report formats
-- Webhook management improvements
-
----
-
-## Worktrees Status
-All old worktrees cleaned up. Ready for new issue work.
-
----
-
-## Dev-Loop Metadata
-- **Repo:** /home/ubuntu/review-bot
-- **Main branch SHA:** ed3a5dd (last commit)
-- **Cron ID:** 5342ac81-4bbc-4e4c-a123-347a7788d50c
-- **Scheduled:** Every 4 hours
-- **Last health check:** 2026-05-14 20:10 UTC (✅ all healthy)
-
-## Self-Review: review-bot-issue-130-work — 2026-05-14
-
-### Verdict: NEEDS_WORK
-
-- [x] [completeness] `VCS_TYPE` env var is detected in `main.go` but **not passed from `action.yml`'s `Run review` step** to the binary. The binary falls back to a URL heuristic (`github.com` / `github.concur.com` substrings), which will silently misclassify any GitHub Enterprise Server whose hostname does not contain `github`. The action already has `vcs_type` as a step output — it should be passed as `VCS_TYPE: ${{ steps.version.outputs.vcs_type }}` in the `Run review` env block.
-- [x] [completeness] `README.md` still references `GITEA_REPO` and `$GITEA_TOKEN` in the CLI example (line ~288) and the env var table (line ~303). Now that the binary supports GitHub too, these should be renamed to VCS-agnostic names (`VCS_REPO`/`REPO`, `VCS_TOKEN`/`REVIEWER_TOKEN`) or at minimum the env var table should note GitHub support.
-- [x] [fit] `vcsReviewComment.NewPosition` field comment says "Gitea: absolute line; GitHub: diff hunk position" but in `githubVCSAdapter.PostReview` it is actually mapped to `Line` (absolute line) + `Side: "RIGHT"`, not to `Position` (hunk position). The field name and comment are now slightly misleading — the field means "new line number" for Gitea and is repurposed as "absolute line" for GitHub. Consider renaming to `Line` or `NewLine` with a clearer comment explaining the per-backend semantics.
-- [x] [instinct] `validateurl.go` imports `gitea` package for `gitea.IsBlockedIP` — this creates a dependency from the GitHub-generic `validateurl.go` on the Gitea-specific package. The `IsBlockedIP` function is a general networking utility. Consider moving it to a shared `internal/netutil` package (or keeping it in `gitea` and accepting the coupling), but the current import is an unexpected relationship.

cmd/review-bot/integration_test.go

@@ -17,7 +17,7 @@ import (
 // Integration test requires a running Gitea instance and LLM endpoint.
 // Set environment variables:
 //
-//	INTEGRATION_VCS_URL       - VCS base URL
+//	INTEGRATION_GITEA_URL     - Gitea base URL
 //	INTEGRATION_GITEA_TOKEN   - Gitea API token with repo access
 //	INTEGRATION_GITEA_REPO    - owner/repo with an open PR
 //	INTEGRATION_PR_NUMBER     - PR number to test against
@@ -25,7 +25,7 @@ import (
 //	INTEGRATION_LLM_API_KEY   - LLM API key
 //	INTEGRATION_LLM_MODEL     - Model name
 func TestIntegration_FullReviewFlow(t *testing.T) {
-	giteaURL := os.Getenv("INTEGRATION_VCS_URL")
+	giteaURL := os.Getenv("INTEGRATION_GITEA_URL")
 	giteaToken := os.Getenv("INTEGRATION_GITEA_TOKEN")
 	giteaRepo := os.Getenv("INTEGRATION_GITEA_REPO")
 	prNumStr := os.Getenv("INTEGRATION_PR_NUMBER")
@@ -104,7 +104,7 @@ func TestIntegration_FullReviewFlow(t *testing.T) {
 }
 
 func TestIntegration_PostAndCleanup(t *testing.T) {
-	giteaURL := os.Getenv("INTEGRATION_VCS_URL")
+	giteaURL := os.Getenv("INTEGRATION_GITEA_URL")
 	giteaToken := os.Getenv("INTEGRATION_GITEA_TOKEN")
 	giteaRepo := os.Getenv("INTEGRATION_GITEA_REPO")
 	prNumStr := os.Getenv("INTEGRATION_PR_NUMBER")
@@ -130,7 +130,7 @@ func TestIntegration_PostAndCleanup(t *testing.T) {
 	// Post a test review
 	sentinel := "<!-- review-bot:integration-test -->"
 	testBody := "# Integration Test Review\n\nThis is a test review.\n\n" + sentinel
-	posted, err := giteaClient.PostReview(ctx, owner, repoName, prNumber, "COMMENT", testBody, "", nil)
+	posted, err := giteaClient.PostReview(ctx, owner, repoName, prNumber, "COMMENT", testBody, nil)
 	if err != nil {
 		t.Fatalf("PostReview: %v", err)
 	}

cmd/review-bot/main.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"flag"
 	"fmt"
-	"io"
 	"log/slog"
 	"os"
 	"path/filepath"
@@ -17,17 +16,11 @@ import (
 	"gitea.weiker.me/rodin/review-bot/github"
 	"gitea.weiker.me/rodin/review-bot/llm"
 	"gitea.weiker.me/rodin/review-bot/review"
+	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 var version = "dev"
 
-// outWriter and errWriter are the output and error writers for subcommands.
-// They are variables so tests can capture output.
-var (
-	outWriter io.Writer = os.Stdout
-	errWriter io.Writer = os.Stderr
-)
-
 // setupLogger configures the global slog default logger based on format and verbosity.
 func setupLogger(format, verbosity string) {
 	var level slog.Level
@@ -58,33 +51,26 @@ func setupLogger(format, verbosity string) {
 }
 
 func main() {
-	// Dispatch subcommands before flag parsing so they get their own args.
-	// e.g. `review-bot validate-url <url>`
-	if len(os.Args) > 1 {
-		switch os.Args[1] {
-		case "validate-url":
-			os.Exit(runValidateURL(os.Args[2:]))
-		}
-	}
-
 	versionFlag := flag.Bool("version", false, "Print version and exit")
 	// Logging flags
 	logFormat := flag.String("log-format", envOrDefault("LOG_FORMAT", "text"), "Log output format: text or json")
 	verbosity := flag.String("verbosity", envOrDefault("LOG_VERBOSITY", "info"), "Log verbosity: debug, info, warn, error")
-	// CLI flags
-	vcsURL := flag.String("vcs-url", os.Getenv("VCS_URL"), "VCS server URL (e.g. https://gitea.example.com)")
-	giteaURLAlias := flag.String("gitea-url", "", "Deprecated: use --vcs-url")
-	repo := flag.String("repo", envOrDefault("GITEA_REPO", ""), "Repository (owner/name)")
+	// VCS flags
+	provider := flag.String("provider", envOrDefault("VCS_PROVIDER", "gitea"), "VCS provider: gitea or github")
+	baseURL := flag.String("base-url", envOrDefault("VCS_BASE_URL", ""), "VCS API base URL (for github provider; defaults to https://api.github.com)")
+	vcsURL := flag.String("vcs-url", envOrDefault("VCS_URL", envOrDefault("GITEA_URL", envOrDefault("GITHUB_SERVER_URL", ""))), "VCS instance URL (Gitea) [deprecated alias: --gitea-url]")
+	// Keep --gitea-url as backward-compatible alias (flag package doesn't support aliases natively, handle below)
+	repo := flag.String("repo", envOrDefault("VCS_REPO", envOrDefault("GITEA_REPO", envOrDefault("GITHUB_REPOSITORY", ""))), "Repository (owner/name)")
 	prNum := flag.String("pr", envOrDefault("PR_NUMBER", ""), "Pull request number")
 	reviewerName := flag.String("reviewer-name", envOrDefault("REVIEWER_NAME", ""), "Reviewer display name")
-	reviewerToken := flag.String("reviewer-token", envOrDefault("REVIEWER_TOKEN", ""), "Gitea token for posting review")
+	reviewerToken := flag.String("reviewer-token", envOrDefault("REVIEWER_TOKEN", ""), "VCS token for posting review")
 	llmBaseURL := flag.String("llm-base-url", envOrDefault("LLM_BASE_URL", ""), "LLM API base URL")
 	llmAPIKey := flag.String("llm-api-key", envOrDefault("LLM_API_KEY", ""), "LLM API key")
 	llmModel := flag.String("llm-model", envOrDefault("LLM_MODEL", ""), "LLM model name")
 	conventionsFile := flag.String("conventions-file", envOrDefault("CONVENTIONS_FILE", ""), "Conventions file path in repo (e.g. CLAUDE.md)")
 	systemPromptFile := flag.String("system-prompt-file", envOrDefault("SYSTEM_PROMPT_FILE", ""), "Local file with additional system prompt instructions")
 	patternsRepo := flag.String("patterns-repo", envOrDefault("PATTERNS_REPO", ""), "Repo with language patterns (e.g. rodin/elixir-patterns)")
-	patternsFiles := flag.String("patterns-files", envOrDefault("PATTERNS_FILES", ""), "Comma-separated file paths to fetch from patterns repo (empty = all files)")
+	patternsFiles := flag.String("patterns-files", envOrDefault("PATTERNS_FILES", "README.md"), "Comma-separated file paths to fetch from patterns repo")
 	dryRun := flag.Bool("dry-run", false, "Print review to stdout instead of posting")
 	llmTemp := flag.Float64("llm-temperature", envOrDefaultFloat("LLM_TEMPERATURE", 0), "LLM temperature (0 = server default)")
 	llmTimeout := flag.Int("llm-timeout", envOrDefaultInt("LLM_TIMEOUT", 300), "LLM request timeout in seconds (default 300)")
@@ -98,6 +84,11 @@ func main() {
 	aicoreAPIURL := flag.String("aicore-api-url", envOrDefault("AICORE_API_URL", ""), "SAP AI Core API URL (for provider=aicore)")
 	aicoreResourceGroup := flag.String("aicore-resource-group", envOrDefault("AICORE_RESOURCE_GROUP", "default"), "SAP AI Core resource group (for provider=aicore)")
 
+	// Backward-compatible alias: --gitea-url shares vcsURL's pointer (last flag wins).
+	// Must use *vcsURL as default: StringVar sets *p=value at registration, so empty
+	// string would overwrite the env-resolved value from the --vcs-url declaration.
+	flag.StringVar(vcsURL, "gitea-url", *vcsURL, "Deprecated: use --vcs-url instead")
+
 	flag.Parse()
 
 	if *versionFlag {
@@ -110,24 +101,23 @@ func main() {
 
 	slog.Info("review-bot starting", "version", version)
 
-	// Backward compatibility: fall back to deprecated env var / flag if VCS_URL / --vcs-url not set.
-	if *vcsURL == "" {
-		if v := os.Getenv("GITEA_URL"); v != "" {
-			slog.Warn("GITEA_URL is deprecated; rename the environment variable to VCS_URL")
-			*vcsURL = v
-		}
-	}
-	if *vcsURL == "" && *giteaURLAlias != "" {
-		slog.Warn("--gitea-url is deprecated; use --vcs-url instead")
-		*vcsURL = *giteaURLAlias
+	// Validate VCS provider
+	vcsProvider := vcs.VCSProvider(*provider)
+	if !vcsProvider.Valid() {
+		fmt.Fprintf(os.Stderr, "Error: invalid --provider %q (valid: gitea, github)\n", *provider)
+		os.Exit(1)
 	}
 
 	// Validate required fields
-	// For aicore provider, llm-base-url and llm-api-key are not required
 	isAICore := llm.Provider(*llmProvider) == llm.ProviderAICore
-	if *vcsURL == "" || *repo == "" || *prNum == "" || *reviewerToken == "" || *llmModel == "" {
+	if *repo == "" || *prNum == "" || *reviewerToken == "" || *llmModel == "" {
 		fmt.Fprintf(os.Stderr, "Error: missing required flags or environment variables\n\n")
-		fmt.Fprintf(os.Stderr, "Required: --vcs-url, --repo, --pr, --reviewer-token, --llm-model\n")
+		fmt.Fprintf(os.Stderr, "Required: --repo, --pr, --reviewer-token, --llm-model\n")
+		os.Exit(1)
+	}
+	// --vcs-url is required only for gitea provider
+	if vcsProvider == vcs.ProviderGitea && *vcsURL == "" {
+		fmt.Fprintf(os.Stderr, "Error: --vcs-url (or --gitea-url) is required for provider=gitea\n")
 		os.Exit(1)
 	}
 	if !isAICore && (*llmBaseURL == "" || *llmAPIKey == "") {
@@ -146,8 +136,6 @@ func main() {
 		os.Exit(1)
 	}
 
-	// NOTE: Persona loading deferred until after Gitea client init to support repo personas
-
 	// Validate reviewer-name: only safe characters allowed in sentinel
 	if err := validateReviewerName(*reviewerName); err != nil {
 		slog.Error("invalid reviewer name", "error", err)
@@ -169,40 +157,20 @@ func main() {
 		os.Exit(1)
 	}
 
-	// Initialize clients
-	// Detect VCS type: explicit flag > env var > URL heuristic (default: gitea).
-	vcsType := envOrDefault("VCS_TYPE", "")
-	if vcsType == "" {
-		// Heuristic: if the URL looks like github.com or a GitHub Enterprise host,
-		// default to GitHub. The composite action sets VCS_TYPE explicitly, so this
-		// is a fallback for manual invocations.
-		if strings.Contains(*vcsURL, "github.com") || strings.Contains(*vcsURL, "github.concur.com") {
-			vcsType = "github"
-		} else {
-			vcsType = "gitea"
-		}
-	}
-	slog.Info("VCS type detected", "vcs_type", vcsType, "vcs_url", *vcsURL)
-
-	var vcs vcsClient
-	switch vcsType {
-	case "github":
-		// GitHub: baseURL is the API URL, derived from server URL.
-		// github.com → https://api.github.com
-		// GHES (e.g. https://ghe.example.com) → https://ghe.example.com/api/v3
-		apiURL := githubAPIURL(*vcsURL)
-		ghClient := github.NewClient(*reviewerToken, apiURL)
-		vcs = newGithubVCSAdapter(ghClient)
-		slog.Info("using GitHub VCS client", "api_url", apiURL)
-	case "gitea":
+	// Initialize VCS client
+	var client vcs.Client
+	switch vcsProvider {
+	case vcs.ProviderGitea:
 		giteaClient := gitea.NewClient(*vcsURL, *reviewerToken)
-		vcs = newGiteaVCSAdapter(giteaClient)
-		slog.Info("using Gitea VCS client", "url", *vcsURL)
+		client = gitea.NewAdapter(giteaClient)
+	case vcs.ProviderGitHub:
+		client = github.NewClient(*reviewerToken, *baseURL)
 	default:
-		slog.Error("unsupported VCS type", "vcs_type", vcsType, "valid", "gitea, github")
-		os.Exit(1)
+		panic("unreachable: provider validation should have caught " + vcsProvider.String())
 	}
+	slog.Info("VCS client initialized", "provider", vcsProvider)
 
+	// Initialize LLM client
 	llmClient := llm.NewClient(*llmBaseURL, *llmAPIKey, *llmModel)
 	if *llmTemp < 0 || *llmTemp > 2 {
 		slog.Error("invalid LLM temperature", "temperature", *llmTemp, "range", "0-2")
@@ -236,16 +204,13 @@ func main() {
 	ctx, cancel := context.WithTimeout(context.Background(), overallTimeout)
 	defer cancel()
 
-	// Load persona if specified (after Gitea client init to support repo personas)
+	// Load persona if specified
 	var persona *review.Persona
 	if *personaName != "" {
 		// Try loading from repo first, then fall back to built-in
-		repoPersonas, err := review.LoadRepoPersonas(ctx, vcs, owner, repoName)
+		repoPersonas, err := review.LoadRepoPersonas(ctx, client, owner, repoName)
 		if err != nil {
 			slog.Warn("could not load repo personas", "repo", owner+"/"+repoName, "error", err)
-			// Continue with built-in personas only.
-			// NOTE: repoPersonas is nil here, but map indexing on a nil map is safe in Go
-			// (returns the zero value), so the fallback to built-in below works correctly.
 		}
 		if p, ok := repoPersonas[*personaName]; ok {
 			persona = p
@@ -276,7 +241,7 @@ func main() {
 	slog.Info("reviewing pull request", "pr", prNumber, "repo", fmt.Sprintf("%s/%s", owner, repoName))
 
 	// Step 1: Fetch PR metadata
-	pr, err := vcs.GetPullRequest(ctx, owner, repoName, prNumber)
+	pr, err := client.GetPullRequest(ctx, owner, repoName, prNumber)
 	if err != nil {
 		slog.Error("failed to fetch PR", "pr", prNumber, "error", err)
 		os.Exit(1)
@@ -284,7 +249,7 @@ func main() {
 	slog.Info("fetched PR metadata", "pr", prNumber, "title", pr.Title)
 
 	// Step 2: Fetch diff
-	diff, err := vcs.GetPullRequestDiff(ctx, owner, repoName, prNumber)
+	diff, err := client.GetPullRequestDiff(ctx, owner, repoName, prNumber)
 	if err != nil {
 		slog.Error("failed to fetch diff", "pr", prNumber, "error", err)
 		os.Exit(1)
@@ -293,21 +258,21 @@ func main() {
 
 	// Step 3: Fetch full file content for modified files
 	fileContext := ""
-	files, err := vcs.GetPullRequestFiles(ctx, owner, repoName, prNumber)
+	files, err := client.GetPullRequestFiles(ctx, owner, repoName, prNumber)
 	if err != nil {
 		slog.Warn("could not fetch PR files list", "pr", prNumber, "error", err)
 	} else {
-		fileContext = fetchFileContext(ctx, vcs, owner, repoName, pr.Head.Ref, files)
+		fileContext = fetchFileContext(ctx, client, owner, repoName, pr.Head.Ref, files)
 		slog.Debug("fetched file context", "files", len(files))
 	}
 
 	// Step 4: Check CI status
 	ciPassed := true
 	ciDetails := ""
-	if pr.Head.Sha != "" {
-		statuses, err := vcs.GetCommitStatuses(ctx, owner, repoName, pr.Head.Sha)
+	if pr.Head.SHA != "" {
+		statuses, err := client.GetCommitStatuses(ctx, owner, repoName, pr.Head.SHA)
 		if err != nil {
-			slog.Warn("could not fetch CI status", "sha", pr.Head.Sha, "error", err)
+			slog.Warn("could not fetch CI status", "sha", pr.Head.SHA, "error", err)
 		} else {
 			ciPassed, ciDetails = evaluateCIStatus(statuses)
 			slog.Info("CI status checked", "passed", ciPassed)
@@ -317,7 +282,7 @@ func main() {
 	// Step 5: Load conventions file if specified
 	conventions := ""
 	if *conventionsFile != "" {
-		content, err := vcs.GetFileContent(ctx, owner, repoName, *conventionsFile)
+		content, err := client.GetFileContent(ctx, owner, repoName, *conventionsFile, "")
 		if err != nil {
 			slog.Warn("could not load conventions file", "file", *conventionsFile, "error", err)
 		} else {
@@ -329,7 +294,7 @@ func main() {
 	// Step 6: Load patterns from external repo if specified
 	patterns := ""
 	if *patternsRepo != "" {
-		patterns = fetchPatterns(ctx, vcs, *patternsRepo, *patternsFiles)
+		patterns = fetchPatterns(ctx, client, *patternsRepo, *patternsFiles)
 		slog.Debug("loaded patterns", "repo", *patternsRepo, "bytes", len(patterns))
 	}
 
@@ -422,15 +387,16 @@ func main() {
 	}
 
 	// Add commit footer so readers know which commit was evaluated
-	if pr.Head.Sha != "" {
-		shortSHA := pr.Head.Sha
+	if pr.Head.SHA != "" {
+		shortSHA := pr.Head.SHA
 		if len(shortSHA) > 8 {
 			shortSHA = shortSHA[:8]
 		}
 		reviewBody += fmt.Sprintf("\n\n---\n*Evaluated against %s*", shortSHA)
 	}
 
-	event := review.GiteaEvent(result.Verdict)
+	// Map verdict to canonical review event
+	event := verdictToEvent(result.Verdict)
 
 	if *dryRun {
 		fmt.Println("--- DRY RUN ---")
@@ -442,34 +408,40 @@ func main() {
 	sentinel := fmt.Sprintf("<!-- review-bot:%s -->", *reviewerName)
 
 	// Stale check: verify HEAD hasn't moved since we started
-	evaluatedSHA := pr.Head.Sha
+	evaluatedSHA := pr.Head.SHA
 	var currentSHA string
-	currentPR, err := vcs.GetPullRequest(ctx, owner, repoName, prNumber)
+	currentPR, err := client.GetPullRequest(ctx, owner, repoName, prNumber)
 	if err != nil {
 		slog.Warn("could not re-fetch PR for stale check", "pr", prNumber, "error", err)
-		// currentSHA stays empty — shouldSkipStaleReview will return false
 	} else {
-		currentSHA = currentPR.Head.Sha
+		currentSHA = currentPR.Head.SHA
 	}
 	if shouldSkipStaleReview(evaluatedSHA, currentSHA) {
-		slog.Warn("HEAD moved during review — skipping stale review",
+		slog.Warn("HEAD moved during review -- skipping stale review",
 			"evaluated", evaluatedSHA,
 			"current", currentSHA,
 			"pr", prNumber)
 		return
 	}
 
-	// Map findings to inline comments for lines present in the diff
-	diffRanges := gitea.ParseDiffNewLines(diff)
-	var inlineComments []vcsReviewComment
+	// Build line→position map for inline comments
+	lineToPosition := vcs.BuildLineToPositionMap(diff)
+	var inlineComments []vcs.ReviewComment
 	for _, f := range result.Findings {
-		if f.File != "" && f.Line > 0 && diffRanges.Contains(f.File, f.Line) {
-			inlineComments = append(inlineComments, vcsReviewComment{
-				Path:    f.File,
-				NewLine: int64(f.Line),
-				Body:    fmt.Sprintf("**[%s]** %s", f.Severity, f.Finding),
-			})
+		if f.File == "" || f.Line <= 0 {
+			continue
 		}
+		pos, ok := lineToPosition[f.File][f.Line]
+		if !ok {
+			slog.Warn("line not in diff, skipping comment", "file", f.File, "line", f.Line)
+			continue
+		}
+		inlineComments = append(inlineComments, vcs.ReviewComment{
+			Path:     f.File,
+			Position: pos,
+			CommitID: evaluatedSHA,
+			Body:     fmt.Sprintf("**[%s]** %s", f.Severity, f.Finding),
+		})
 	}
 	if len(inlineComments) > 0 {
 		slog.Debug("attaching inline comments", "count", len(inlineComments))
@@ -478,10 +450,9 @@ func main() {
 	// --- Review update strategy ---
 	// 1. POST new review first (gets non-stale approval badge on HEAD)
 	// 2. Then supersede old review with link to the new one
-	// Order matters: post first so we have the new review's URL for the supersede message.
-	var oldReviews []vcsReview
+	var oldReviews []vcs.Review
 	if *reviewerName != "" {
-		existingReviews, err := vcs.ListReviews(ctx, owner, repoName, prNumber)
+		existingReviews, err := client.ListReviews(ctx, owner, repoName, prNumber)
 		if err != nil {
 			slog.Warn("could not list existing reviews", "pr", prNumber, "error", err)
 		} else {
@@ -493,79 +464,64 @@ func main() {
 		}
 	}
 
-	// Self-request as reviewer (ensures we appear in required-reviewer checks)
-	authUser, err := vcs.GetAuthenticatedUser(ctx)
-	if err != nil {
-		slog.Warn("could not determine authenticated user for reviewer self-request", "error", err)
-	} else if authUser != "" {
-		if err := vcs.RequestReviewer(ctx, owner, repoName, prNumber, authUser); err != nil {
-			slog.Warn("could not self-request as reviewer", "user", authUser, "error", err)
-		} else {
-			slog.Debug("self-requested as reviewer", "user", authUser, "pr", prNumber)
+	// Self-request as reviewer (Gitea-specific; ensures we appear in required-reviewer checks)
+	if selfReq, ok := client.(vcs.ReviewerSelfRequester); ok {
+		authUser, err := client.GetAuthenticatedUser(ctx)
+		if err != nil {
+			slog.Warn("could not determine authenticated user for reviewer self-request", "error", err)
+		} else if authUser != "" {
+			if err := selfReq.RequestReviewerSelf(ctx, owner, repoName, prNumber, authUser); err != nil {
+				slog.Warn("could not self-request as reviewer", "user", authUser, "error", err)
+			} else {
+				slog.Debug("self-requested as reviewer", "user", authUser, "pr", prNumber)
+			}
 		}
+	} else {
+		slog.Debug("RequestReviewer not supported for provider, skipping")
 	}
 
 	// POST new review
 	slog.Info("posting review", "event", event, "pr", prNumber)
-	posted, err := vcs.PostReview(ctx, owner, repoName, prNumber, event, reviewBody, evaluatedSHA, inlineComments)
+	reviewReq := vcs.ReviewRequest{
+		Body:     reviewBody,
+		Event:    event,
+		CommitID: evaluatedSHA,
+		Comments: inlineComments,
+	}
+	posted, err := client.PostReview(ctx, owner, repoName, prNumber, reviewReq)
 	if err != nil {
 		slog.Error("failed to post review", "pr", prNumber, "event", event, "error", err)
 		os.Exit(1)
 	}
 	slog.Info("review posted", "review_id", posted.ID, "user", posted.User.Login, "pr", prNumber)
 
-	// Supersede all old reviews with link to the new one.
-	// This is only supported on Gitea (requires timeline API); GitHub reviews cannot
-	// be edited after submission, so we skip the supersede step there.
-	extVCS, isGiteaExt := vcs.(giteaExtClient)
-	if len(oldReviews) > 0 && isGiteaExt {
-		newReviewURL := fmt.Sprintf("%s/%s/%s/pulls/%d#pullrequestreview-%d", strings.TrimRight(*vcsURL, "/"), owner, repoName, prNumber, posted.ID)
-		for _, oldReview := range oldReviews {
-			cid, err := extVCS.GetTimelineReviewCommentIDForReview(ctx, owner, repoName, int64(prNumber), oldReview.ID)
-			if err != nil {
-				slog.Warn("could not find comment ID for old review", "review_id", oldReview.ID, "error", err)
-				continue
-			}
-			supersededBody := buildSupersededBody(oldReview.Body, oldReview.CommitID, newReviewURL, sentinel)
-			if err := extVCS.EditComment(ctx, owner, repoName, cid, supersededBody); err != nil {
-				slog.Warn("could not mark old review as superseded", "review_id", oldReview.ID, "comment_id", cid, "error", err)
-				continue
-			}
-			slog.Info("marked old review as superseded", "review_id", oldReview.ID, "new_review_id", posted.ID, "pr", prNumber)
-
-			// Resolve old review's inline comments
-			oldComments, err := extVCS.ListReviewComments(ctx, owner, repoName, int64(prNumber), oldReview.ID)
-			if err != nil {
-				slog.Warn("could not list old review comments for resolution", "review_id", oldReview.ID, "error", err)
-				continue
-			}
-			resolved, failed := 0, 0
-			for _, c := range oldComments {
-				if c.ID == 0 {
-					continue
-				}
-				if err := extVCS.ResolveComment(ctx, owner, repoName, c.ID); err != nil {
-					slog.Debug("could not resolve inline comment", "comment_id", c.ID, "error", err)
-					failed++
-				} else {
-					resolved++
-				}
-			}
-			if resolved > 0 {
-				slog.Info("resolved old inline comments", "review_id", oldReview.ID, "count", resolved, "pr", prNumber)
-			}
-			if failed > 0 {
-				slog.Warn("some inline comments could not be resolved", "review_id", oldReview.ID, "failed", failed, "pr", prNumber)
+	// Supersede all old reviews via optional interface
+	if len(oldReviews) > 0 {
+		if superseder, ok := client.(vcs.ReviewSuperseder); ok {
+			if err := superseder.SupersedeReviews(ctx, owner, repoName, prNumber, oldReviews, posted.ID, *vcsURL, sentinel); err != nil {
+				slog.Error("failed to supersede old reviews", "error", err)
+				os.Exit(1)
 			}
+		} else {
+			slog.Error("provider does not support review superseding", "provider", vcsProvider)
 		}
-	} else if len(oldReviews) > 0 {
-		slog.Info("skipping supersede of old reviews (not supported on this VCS)", "old_count", len(oldReviews), "pr", prNumber)
 	}
+}
 
+// verdictToEvent maps a verdict string from the LLM response to a canonical vcs.ReviewEvent.
+func verdictToEvent(verdict string) vcs.ReviewEvent {
+	switch verdict {
+	case "APPROVE":
+		return vcs.ReviewEventApprove
+	case "REQUEST_CHANGES":
+		return vcs.ReviewEventRequestChanges
+	default:
+		return vcs.ReviewEventComment
+	}
 }
 
 // fetchFileContext fetches the full content of modified files from the PR branch.
-func fetchFileContext(ctx context.Context, client vcsClient, owner, repo, ref string, files []vcsChangedFile) string {
+func fetchFileContext(ctx context.Context, client vcs.PRReader, owner, repo, ref string, files []vcs.ChangedFile) string {
 	var sb strings.Builder
 	for _, f := range files {
 		if ctx.Err() != nil {
@@ -574,7 +530,7 @@ func fetchFileContext(ctx context.Context, client vcsClient, owner, repo, ref st
 		if f.Status == "removed" {
 			continue // Skip deleted files
 		}
-		content, err := client.GetFileContentRef(ctx, owner, repo, f.Filename, ref)
+		content, err := client.GetFileContentAtRef(ctx, owner, repo, f.Filename, ref)
 		if err != nil {
 			slog.Warn("could not fetch file content", "file", f.Filename, "error", err)
 			continue
@@ -591,25 +547,12 @@ func fetchFileContext(ctx context.Context, client vcsClient, owner, repo, ref st
 // patternsRepo is comma-separated list of owner/name repos.
 // patternsFiles is comma-separated list of file paths or directories.
 // If a path ends with / or is a directory, all files within it are fetched recursively.
-// If patternsFiles is empty, all files from the repo root are fetched.
-func fetchPatterns(ctx context.Context, client vcsClient, patternsRepo, patternsFiles string) string {
+// Empty entries in patternsFiles are skipped (no implicit repo-root fetch).
+func fetchPatterns(ctx context.Context, client vcs.FileReader, patternsRepo, patternsFiles string) string {
 	var sb strings.Builder
 
 	repos := strings.Split(patternsRepo, ",")
-
-	// Build the list of paths to fetch
-	var paths []string
-	if patternsFiles == "" {
-		// Empty patternsFiles means "fetch all files from repo root"
-		paths = []string{""}
-	} else {
-		for _, p := range strings.Split(patternsFiles, ",") {
-			p = strings.TrimSpace(p)
-			if p != "" {
-				paths = append(paths, p)
-			}
-		}
-	}
+	paths := strings.Split(patternsFiles, ",")
 
 	for _, repoRef := range repos {
 		if ctx.Err() != nil {
@@ -630,7 +573,12 @@ func fetchPatterns(ctx context.Context, client vcsClient, patternsRepo, patterns
 		var repoSkippedFiles []string
 
 		for _, path := range paths {
-			files, err := client.GetAllFilesInPath(ctx, owner, repo, path)
+			path = strings.TrimSpace(path)
+			if path == "" {
+				continue
+			}
+
+			files, err := vcs.GetAllFilesInPath(ctx, client, owner, repo, path)
 			if err != nil {
 				slog.Warn("could not fetch patterns", "path", path, "repo", repoRef, "error", err)
 				continue
@@ -669,18 +617,20 @@ func isPatternFile(path string) bool {
 }
 
 // evaluateCIStatus checks if all CI statuses indicate success.
-func evaluateCIStatus(statuses []vcsCommitStatus) (passed bool, details string) {
+// Returns passed=true if no checks have failed (pending checks are not treated as failures).
+func evaluateCIStatus(statuses []vcs.CommitStatus) (passed bool, details string) {
 	if len(statuses) == 0 {
 		return true, "no CI statuses found"
 	}
 
 	var failed []string
+	var pending int
 	for _, s := range statuses {
 		switch s.Status {
 		case "success":
 			// good
 		case "pending":
-			// treat pending as not-failed
+			pending++
 		case "failure", "error":
 			failed = append(failed, fmt.Sprintf("%s: %s", s.Context, s.Description))
 		}
@@ -689,20 +639,10 @@ func evaluateCIStatus(statuses []vcsCommitStatus) (passed bool, details string)
 	if len(failed) > 0 {
 		return false, strings.Join(failed, "; ")
 	}
-	return true, "all checks passed"
-}
-
-// githubAPIURL converts a GitHub server URL to its API base URL.
-// github.com → https://api.github.com
-// GHES (e.g. https://ghe.example.com) → https://ghe.example.com/api/v3
-func githubAPIURL(serverURL string) string {
-	const canonicalGitHub = "https://github.com"
-	const githubAPIBase = "https://api.github.com"
-	if serverURL == "" || strings.TrimRight(serverURL, "/") == canonicalGitHub {
-		return githubAPIBase
+	if pending > 0 {
+		return true, fmt.Sprintf("no failures (%d pending)", pending)
 	}
-	// GitHub Enterprise Server: /api/v3 suffix
-	return strings.TrimRight(serverURL, "/") + "/api/v3"
+	return true, "all checks passed"
 }
 
 func envOrDefault(key, defaultVal string) string {
@@ -732,14 +672,6 @@ func envOrDefaultInt(key string, defaultVal int) int {
 	return defaultVal
 }
 
-func envOrDefaultBool(key string, defaultVal bool) bool {
-	v := strings.TrimSpace(strings.ToLower(os.Getenv(key)))
-	if v == "" {
-		return defaultVal
-	}
-	return v == "true" || v == "1" || v == "yes"
-}
-
 // validateReviewerName checks that the name contains only safe characters
 // for embedding in an HTML comment sentinel ([a-zA-Z0-9_-]).
 func validateReviewerName(name string) error {
@@ -791,36 +723,11 @@ func validateWorkspacePath(path, pathName string) (string, error) {
 	return resolvedPath, nil
 }
 
-// buildSupersededBody creates the body for a superseded review: struck-through banner
-// with collapsed original content and the commit it was evaluated against.
-func buildSupersededBody(originalBody, commitSHA, newReviewURL, sentinel string) string {
-	shortSHA := commitSHA
-	if len(shortSHA) > 8 {
-		shortSHA = shortSHA[:8]
-	}
-	var sb strings.Builder
-	sb.WriteString("~~Original review~~\n\n")
-	sb.WriteString("**Superseded** \u2014 [see current review](")
-	sb.WriteString(newReviewURL)
-	sb.WriteString(") for up-to-date findings.\n\n")
-	if shortSHA != "" {
-		sb.WriteString("<details><summary>Previous findings (commit ")
-		sb.WriteString(shortSHA)
-		sb.WriteString(")</summary>\n\n")
-	} else {
-		sb.WriteString("<details><summary>Previous findings</summary>\n\n")
-	}
-	sb.WriteString(originalBody)
-	sb.WriteString("\n\n</details>\n\n")
-	sb.WriteString(sentinel)
-	return sb.String()
-}
-
 // hasSharedToken detects if another review-bot role posted under the same
-// Gitea user. This indicates misconfiguration where two roles share a token
-// instead of having separate Gitea accounts. Returns true if shared token
+// VCS user. This indicates misconfiguration where two roles share a token
+// instead of having separate accounts. Returns true if shared token
 // detected (caller should skip update-in-place logic to avoid clobbering).
-func hasSharedToken(reviews []vcsReview, ownSentinel string) bool {
+func hasSharedToken(reviews []vcs.Review, ownSentinel string) bool {
 	ownLogin := ""
 	for _, r := range reviews {
 		if strings.Contains(r.Body, ownSentinel) {
@@ -833,7 +740,7 @@ func hasSharedToken(reviews []vcsReview, ownSentinel string) bool {
 	}
 	for _, r := range reviews {
 		if r.User.Login == ownLogin && strings.Contains(r.Body, "<!-- review-bot:") && !strings.Contains(r.Body, ownSentinel) {
-			slog.Warn("shared token detected — another review-bot role is using the same Gitea user",
+			slog.Warn("shared token detected -- another review-bot role is using the same VCS user",
 				"sibling_role", extractSentinelName(r.Body), "user", ownLogin)
 			return true
 		}
@@ -854,29 +761,26 @@ func extractSentinelName(body string) string {
 	if end < 0 {
 		return "unknown"
 	}
-	return rest[:end]
-}
-
-// findOwnReview locates the most recent non-superseded review matching the sentinel.
-func findOwnReview(reviews []vcsReview, sentinel string) *vcsReview {
-	var best *vcsReview
-	for i := range reviews {
-		if !strings.Contains(reviews[i].Body, sentinel) {
-			continue
-		}
-		if strings.Contains(reviews[i].Body, "~~Original review~~") {
-			continue
-		}
-		if best == nil || reviews[i].ID > best.ID {
-			best = &reviews[i]
+	name := rest[:end]
+	// Sanitize: strip control characters to prevent log injection.
+	name = strings.Map(func(r rune) rune {
+		if r < 0x20 || r == 0x7f {
+			return -1
 		}
+		return r
+	}, name)
+	if len(name) > 64 {
+		name = name[:64]
 	}
-	return best
+	if name == "" {
+		return "unknown"
+	}
+	return name
 }
 
 // findAllOwnReviews returns all non-superseded reviews matching the sentinel.
-func findAllOwnReviews(reviews []vcsReview, sentinel string) []vcsReview {
-	var result []vcsReview
+func findAllOwnReviews(reviews []vcs.Review, sentinel string) []vcs.Review {
+	var result []vcs.Review
 	for i := range reviews {
 		if !strings.Contains(reviews[i].Body, sentinel) {
 			continue
@@ -901,5 +805,3 @@ func shouldSkipStaleReview(evaluatedSHA, currentSHA string) bool {
 	}
 	return evaluatedSHA != currentSHA
 }
-
-

cmd/review-bot/main_test.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 	"testing"
 
+	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 func TestValidateReviewerName(t *testing.T) {
@@ -106,9 +107,7 @@ func TestValidateWorkspacePath(t *testing.T) {
 			workspace: tmpDir,
 			path:      "/etc/passwd",
 			wantErr:   true,
-			// Go 1.21+ filepath.Join normalizes absolute paths: Join("/tmp/x", "/etc/passwd")
-			// becomes "/tmp/x/etc/passwd", which is within workspace but doesn't exist.
-			errMatch: "failed to resolve",
+			errMatch:  "failed to resolve",
 		},
 		{
 			name:      "nonexistent file",
@@ -153,154 +152,20 @@ func TestValidateWorkspacePath(t *testing.T) {
 	}
 }
 
-func makeReview(id int64, login, state string, _ bool, body string) vcsReview {
-	r := vcsReview{
+func makeReview(id int64, login, state string, stale bool, body string) vcs.Review {
+	return vcs.Review{
 		ID:    id,
 		Body:  body,
+		User:  vcs.UserInfo{Login: login},
 		State: state,
-	}
-	r.User.Login = login
-	return r
-}
-
-func TestBuildSupersededBody(t *testing.T) {
-	original := "# Review\n\nLooks good.\n\n<!-- review-bot:sonnet -->"
-	sentinel := "<!-- review-bot:sonnet -->"
-	newURL := "https://gitea.example.com/owner/repo/pulls/1#pullrequestreview-99"
-
-	result := buildSupersededBody(original, "abcdef1234567890", newURL, sentinel)
-
-	// Should contain the struck-through banner
-	if !strings.Contains(result, "~~Original review~~") {
-		t.Error("missing struck-through banner")
-	}
-	// Should contain superseded notice with link
-	if !strings.Contains(result, "**Superseded**") {
-		t.Error("missing superseded notice")
-	}
-	if !strings.Contains(result, "[see current review]("+newURL+")") {
-		t.Error("missing link to new review")
-	}
-	// Should contain collapsed original
-	if !strings.Contains(result, "<details>") {
-		t.Error("missing details/collapse")
-	}
-	// Should contain short commit SHA
-	if !strings.Contains(result, "abcdef12") {
-		t.Error("missing short SHA")
-	}
-	// Should NOT contain full SHA
-	if strings.Contains(result, "abcdef1234567890") {
-		t.Error("should truncate SHA to 8 chars")
-	}
-	// Should contain the original body inside details
-	if !strings.Contains(result, original) {
-		t.Error("original body not preserved in collapsed section")
-	}
-	// Should end with sentinel
-	if !strings.Contains(result, sentinel) {
-		t.Error("missing sentinel")
-	}
-}
-
-func TestBuildSupersededBodyShortSHA(t *testing.T) {
-	// Short SHA should pass through without panic
-	result := buildSupersededBody("body", "abc", "https://example.com/review", "<!-- review-bot:x -->")
-	if !strings.Contains(result, "abc") {
-		t.Error("short SHA not preserved")
-	}
-}
-
-func TestFindOwnReview(t *testing.T) {
-	tests := []struct {
-		name     string
-		reviews  []vcsReview
-		sentinel string
-		wantID   int64
-		wantNil  bool
-	}{
-		{
-			name:     "no reviews",
-			reviews:  nil,
-			sentinel: "<!-- review-bot:sonnet -->",
-			wantNil:  true,
-		},
-		{
-			name: "found by sentinel",
-			reviews: []vcsReview{
-				makeReview(42, "bot", "APPROVED", false, "review body\n<!-- review-bot:sonnet -->"),
-			},
-			sentinel: "<!-- review-bot:sonnet -->",
-			wantID:   42,
-		},
-		{
-			name: "wrong sentinel",
-			reviews: []vcsReview{
-				makeReview(42, "bot", "APPROVED", false, "body\n<!-- review-bot:gpt -->"),
-			},
-			sentinel: "<!-- review-bot:sonnet -->",
-			wantNil:  true,
-		},
-		{
-			name: "multiple reviews, returns first match",
-			reviews: []vcsReview{
-				makeReview(10, "bot", "APPROVED", false, "old\n<!-- review-bot:gpt -->"),
-				makeReview(20, "bot", "APPROVED", false, "new\n<!-- review-bot:sonnet -->"),
-			},
-			sentinel: "<!-- review-bot:sonnet -->",
-			wantID:   20,
-		},
-		{
-			name: "skips superseded review",
-			reviews: []vcsReview{
-				makeReview(10, "bot", "APPROVED", false, "~~Original review~~\n\n**Superseded**\n<!-- review-bot:sonnet -->"),
-				makeReview(20, "bot", "APPROVED", false, "fresh review\n<!-- review-bot:sonnet -->"),
-			},
-			sentinel: "<!-- review-bot:sonnet -->",
-			wantID:   20,
-		},
-		{
-			name: "only superseded reviews exist",
-			reviews: []vcsReview{
-				makeReview(10, "bot", "APPROVED", false, "~~Original review~~\n\n<!-- review-bot:sonnet -->"),
-			},
-			sentinel: "<!-- review-bot:sonnet -->",
-			wantNil:  true,
-		},
-		{
-			name: "picks highest ID among matches",
-			reviews: []vcsReview{
-				makeReview(50, "bot", "APPROVED", false, "v1\n<!-- review-bot:sonnet -->"),
-				makeReview(30, "bot", "APPROVED", false, "v0\n<!-- review-bot:sonnet -->"),
-			},
-			sentinel: "<!-- review-bot:sonnet -->",
-			wantID:   50,
-		},
-	}
-
-	for _, tc := range tests {
-		t.Run(tc.name, func(t *testing.T) {
-			got := findOwnReview(tc.reviews, tc.sentinel)
-			if tc.wantNil {
-				if got != nil {
-					t.Errorf("findOwnReview() = %v, want nil", got)
-				}
-			} else {
-				if got == nil {
-					t.Fatal("findOwnReview() = nil, want non-nil")
-				}
-				if got.ID != tc.wantID {
-					t.Errorf("findOwnReview().ID = %d, want %d", got.ID, tc.wantID)
-				}
-			}
-		})
+		Stale: stale,
 	}
 }
 
 func TestHasSharedToken(t *testing.T) {
 	tests := []struct {
 		name     string
-		reviews  []vcsReview
+		reviews  []vcs.Review
 		sentinel string
 		want     bool
 	}{
@@ -312,36 +177,36 @@ func TestHasSharedToken(t *testing.T) {
 		},
 		{
 			name: "no own review yet - cannot detect",
-			reviews: []vcsReview{
-				{ID: 1, User: struct{ Login string }{Login: "other"}, Body: "<!-- review-bot:gpt --> body"},
+			reviews: []vcs.Review{
+				makeReview(1, "other", "APPROVED", false, "<!-- review-bot:gpt --> body"),
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
 			want:     false,
 		},
 		{
 			name: "separate users - no shared token",
-			reviews: []vcsReview{
-				{ID: 1, User: struct{ Login string }{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:sonnet --> body"},
-				{ID: 2, User: struct{ Login string }{Login: "security-review-bot"}, Body: "<!-- review-bot:security --> body"},
+			reviews: []vcs.Review{
+				makeReview(1, "sonnet-review-bot", "APPROVED", false, "<!-- review-bot:sonnet --> body"),
+				makeReview(2, "security-review-bot", "APPROVED", false, "<!-- review-bot:security --> body"),
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
 			want:     false,
 		},
 		{
 			name: "shared token detected - same user different sentinels",
-			reviews: []vcsReview{
-				{ID: 1, User: struct{ Login string }{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:sonnet --> body"},
-				{ID: 2, User: struct{ Login string }{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:security --> body"},
+			reviews: []vcs.Review{
+				makeReview(1, "sonnet-review-bot", "APPROVED", false, "<!-- review-bot:sonnet --> body"),
+				makeReview(2, "sonnet-review-bot", "APPROVED", false, "<!-- review-bot:security --> body"),
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
 			want:     true,
 		},
 		{
 			name: "three roles same user",
-			reviews: []vcsReview{
-				{ID: 1, User: struct{ Login string }{Login: "bot"}, Body: "<!-- review-bot:sonnet --> body"},
-				{ID: 2, User: struct{ Login string }{Login: "bot"}, Body: "<!-- review-bot:security --> body"},
-				{ID: 3, User: struct{ Login string }{Login: "bot"}, Body: "<!-- review-bot:gpt --> body"},
+			reviews: []vcs.Review{
+				makeReview(1, "bot", "APPROVED", false, "<!-- review-bot:sonnet --> body"),
+				makeReview(2, "bot", "APPROVED", false, "<!-- review-bot:security --> body"),
+				makeReview(3, "bot", "APPROVED", false, "<!-- review-bot:gpt --> body"),
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
 			want:     true,
@@ -502,56 +367,10 @@ func TestIsPatternFile(t *testing.T) {
 	}
 }
 
-// TestBuildPatternPaths verifies the path-building logic for fetchPatterns.
-// Empty patternsFiles means "fetch all from root" (represented as [""]).
-func TestBuildPatternPaths(t *testing.T) {
-	buildPaths := func(patternsFiles string) []string {
-		if patternsFiles == "" {
-			return []string{""}
-		}
-		var paths []string
-		for _, p := range strings.Split(patternsFiles, ",") {
-			p = strings.TrimSpace(p)
-			if p != "" {
-				paths = append(paths, p)
-			}
-		}
-		return paths
-	}
-
-	tests := []struct {
-		name  string
-		input string
-		want  []string
-	}{
-		{"empty fetches root", "", []string{""}},
-		{"single file", "README.md", []string{"README.md"}},
-		{"multiple files", "README.md,PATTERNS.md", []string{"README.md", "PATTERNS.md"}},
-		{"trims whitespace", " foo.md , bar.md ", []string{"foo.md", "bar.md"}},
-		{"skips empty between commas", "foo.md,,bar.md", []string{"foo.md", "bar.md"}},
-		{"directory path", "patterns/", []string{"patterns/"}},
-	}
-
-	for _, tc := range tests {
-		t.Run(tc.name, func(t *testing.T) {
-			got := buildPaths(tc.input)
-			if len(got) != len(tc.want) {
-				t.Errorf("buildPaths(%q) = %v, want %v", tc.input, got, tc.want)
-				return
-			}
-			for i := range got {
-				if got[i] != tc.want[i] {
-					t.Errorf("buildPaths(%q)[%d] = %q, want %q", tc.input, i, got[i], tc.want[i])
-				}
-			}
-		})
-	}
-}
-
 func TestEvaluateCIStatus(t *testing.T) {
 	tests := []struct {
 		name       string
-		statuses   []vcsCommitStatus
+		statuses   []vcs.CommitStatus
 		wantPassed bool
 		wantSubstr string
 	}{
@@ -563,7 +382,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "all success",
-			statuses: []vcsCommitStatus{
+			statuses: []vcs.CommitStatus{
 				{Status: "success", Context: "ci/build", Description: "Build passed"},
 				{Status: "success", Context: "ci/test", Description: "Tests passed"},
 			},
@@ -572,7 +391,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "one failure",
-			statuses: []vcsCommitStatus{
+			statuses: []vcs.CommitStatus{
 				{Status: "success", Context: "ci/build", Description: "Build passed"},
 				{Status: "failure", Context: "ci/test", Description: "Tests failed"},
 			},
@@ -581,7 +400,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "error status",
-			statuses: []vcsCommitStatus{
+			statuses: []vcs.CommitStatus{
 				{Status: "error", Context: "ci/lint", Description: "Lint error"},
 			},
 			wantPassed: false,
@@ -589,16 +408,16 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "pending treated as not-failed",
-			statuses: []vcsCommitStatus{
+			statuses: []vcs.CommitStatus{
 				{Status: "pending", Context: "ci/build", Description: "In progress"},
 				{Status: "success", Context: "ci/test", Description: "Tests passed"},
 			},
 			wantPassed: true,
-			wantSubstr: "all checks passed",
+			wantSubstr: "no failures",
 		},
 		{
 			name: "multiple failures",
-			statuses: []vcsCommitStatus{
+			statuses: []vcs.CommitStatus{
 				{Status: "failure", Context: "ci/build", Description: "Build failed"},
 				{Status: "failure", Context: "ci/test", Description: "Tests failed"},
 			},
@@ -607,7 +426,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "mixed with pending and failure",
-			statuses: []vcsCommitStatus{
+			statuses: []vcs.CommitStatus{
 				{Status: "success", Context: "ci/build", Description: "Build passed"},
 				{Status: "pending", Context: "ci/deploy", Description: "Deploying"},
 				{Status: "failure", Context: "ci/test", Description: "Tests failed"},
@@ -729,47 +548,6 @@ func TestEnvOrDefaultInt(t *testing.T) {
 	}
 }
 
-func TestEnvOrDefaultBool(t *testing.T) {
-	tests := []struct {
-		name       string
-		envVal     string
-		setEnv     bool
-		defaultVal bool
-		want       bool
-	}{
-		{"unset returns default true", "", false, true, true},
-		{"unset returns default false", "", false, false, false},
-		{"true", "true", true, false, true},
-		{"TRUE", "TRUE", true, false, true},
-		{"True", "True", true, false, true},
-		{"1", "1", true, false, true},
-		{"yes", "yes", true, false, true},
-		{"YES", "YES", true, false, true},
-		{"false", "false", true, true, false},
-		{"0", "0", true, true, false},
-		{"no", "no", true, true, false},
-		{"random string", "random", true, true, false},
-		{"empty string returns default", "", true, true, true},
-		{"whitespace true", "  true  ", true, false, true},
-	}
-
-	for _, tc := range tests {
-		t.Run(tc.name, func(t *testing.T) {
-			envKey := "TEST_ENV_BOOL_" + strings.ReplaceAll(tc.name, " ", "_")
-			if tc.setEnv {
-				os.Setenv(envKey, tc.envVal)
-				defer os.Unsetenv(envKey)
-			} else {
-				os.Unsetenv(envKey)
-			}
-			got := envOrDefaultBool(envKey, tc.defaultVal)
-			if got != tc.want {
-				t.Errorf("envOrDefaultBool(%q, %v) = %v, want %v", tc.envVal, tc.defaultVal, got, tc.want)
-			}
-		})
-	}
-}
-
 func TestExtractSentinelName_EdgeCases(t *testing.T) {
 	tests := []struct {
 		body string
@@ -778,8 +556,8 @@ func TestExtractSentinelName_EdgeCases(t *testing.T) {
 		{"<!-- review-bot:sonnet --> rest", "sonnet"},
 		{"<!-- review-bot:gpt-review --> rest", "gpt-review"},
 		{"no sentinel here", "unknown"},
-		{"<!-- review-bot:", "unknown"},                   // prefix but no suffix
-		{"prefix <!-- review-bot:abc --> end", "abc"},     // embedded in text
+		{"<!-- review-bot:", "unknown"},               // prefix but no suffix
+		{"prefix <!-- review-bot:abc --> end", "abc"}, // embedded in text
 	}
 
 	for _, tc := range tests {
@@ -836,7 +614,7 @@ func TestMainSubprocess_InvalidReviewerName(t *testing.T) {
 	if os.Getenv("TEST_SUBPROCESS_MAIN") == "1" {
 		flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
 		os.Args = []string{"review-bot",
-			"--gitea-url", "http://localhost",
+			"--vcs-url", "http://localhost",
 			"--repo", "owner/repo",
 			"--pr", "1",
 			"--reviewer-name", "invalid name",
@@ -864,7 +642,7 @@ func TestMainSubprocess_InvalidRepo(t *testing.T) {
 	if os.Getenv("TEST_SUBPROCESS_MAIN") == "1" {
 		flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
 		os.Args = []string{"review-bot",
-			"--gitea-url", "http://localhost",
+			"--vcs-url", "http://localhost",
 			"--repo", "invalidrepo",
 			"--pr", "1",
 			"--reviewer-token", "tok",
@@ -891,7 +669,7 @@ func TestMainSubprocess_InvalidPRNumber(t *testing.T) {
 	if os.Getenv("TEST_SUBPROCESS_MAIN") == "1" {
 		flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
 		os.Args = []string{"review-bot",
-			"--gitea-url", "http://localhost",
+			"--vcs-url", "http://localhost",
 			"--repo", "owner/repo",
 			"--pr", "notanumber",
 			"--reviewer-token", "tok",
@@ -918,7 +696,7 @@ func TestMainSubprocess_InvalidTemperature(t *testing.T) {
 	if os.Getenv("TEST_SUBPROCESS_MAIN") == "1" {
 		flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
 		os.Args = []string{"review-bot",
-			"--gitea-url", "http://localhost",
+			"--vcs-url", "http://localhost",
 			"--repo", "owner/repo",
 			"--pr", "1",
 			"--reviewer-token", "tok",
@@ -946,7 +724,7 @@ func TestMainSubprocess_InvalidProvider(t *testing.T) {
 	if os.Getenv("TEST_SUBPROCESS_MAIN") == "1" {
 		flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
 		os.Args = []string{"review-bot",
-			"--gitea-url", "http://localhost",
+			"--vcs-url", "http://localhost",
 			"--repo", "owner/repo",
 			"--pr", "1",
 			"--reviewer-token", "tok",
@@ -970,7 +748,35 @@ func TestMainSubprocess_InvalidProvider(t *testing.T) {
 	}
 }
 
-// cleanEnv returns environ without any GITEA/LLM/REVIEWER env vars that would
+func TestMainSubprocess_InvalidVCSProvider(t *testing.T) {
+	if os.Getenv("TEST_SUBPROCESS_MAIN") == "1" {
+		flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ExitOnError)
+		os.Args = []string{"review-bot",
+			"--provider", "invalid",
+			"--vcs-url", "http://localhost",
+			"--repo", "owner/repo",
+			"--pr", "1",
+			"--reviewer-token", "tok",
+			"--llm-base-url", "http://localhost",
+			"--llm-api-key", "key",
+			"--llm-model", "model",
+		}
+		main()
+		return
+	}
+
+	cmd := exec.Command(os.Args[0], "-test.run=TestMainSubprocess_InvalidVCSProvider")
+	cmd.Env = append(cleanEnv(), "TEST_SUBPROCESS_MAIN=1")
+	out, err := cmd.CombinedOutput()
+	if err == nil {
+		t.Fatal("expected non-zero exit with invalid VCS provider")
+	}
+	if !strings.Contains(string(out), "invalid --provider") {
+		t.Errorf("expected error about invalid --provider, got: %s", out)
+	}
+}
+
+// cleanEnv returns environ without any GITEA/LLM/REVIEWER/VCS env vars that would
 // interfere with testing missing-flag scenarios.
 func cleanEnv() []string {
 	var env []string
@@ -978,6 +784,7 @@ func cleanEnv() []string {
 		key := strings.SplitN(e, "=", 2)[0]
 		switch {
 		case strings.HasPrefix(key, "GITEA_"),
+			strings.HasPrefix(key, "VCS_"),
 			strings.HasPrefix(key, "LLM_"),
 			strings.HasPrefix(key, "REVIEWER_"),
 			strings.HasPrefix(key, "PR_"),
@@ -995,12 +802,12 @@ func cleanEnv() []string {
 }
 
 func TestFindAllOwnReviews(t *testing.T) {
-	reviews := []vcsReview{
-		{ID: 1, Body: "<!-- review-bot:sonnet -->\nfirst review"},
-		{ID: 2, Body: "<!-- review-bot:gpt -->\nother bot"},
-		{ID: 3, Body: "<!-- review-bot:sonnet -->\nsecond review"},
-		{ID: 4, Body: "~~Original review~~\n<!-- review-bot:sonnet -->\nsuperseded"},
-		{ID: 5, Body: "<!-- review-bot:sonnet -->\nthird review"},
+	reviews := []vcs.Review{
+		makeReview(1, "bot", "APPROVED", false, "<!-- review-bot:sonnet -->\nfirst review"),
+		makeReview(2, "bot", "APPROVED", false, "<!-- review-bot:gpt -->\nother bot"),
+		makeReview(3, "bot", "APPROVED", false, "<!-- review-bot:sonnet -->\nsecond review"),
+		makeReview(4, "bot", "APPROVED", false, "~~Original review~~\n<!-- review-bot:sonnet -->\nsuperseded"),
+		makeReview(5, "bot", "APPROVED", false, "<!-- review-bot:sonnet -->\nthird review"),
 	}
 
 	got := findAllOwnReviews(reviews, "<!-- review-bot:sonnet -->")
@@ -1064,3 +871,23 @@ func TestShouldSkipStaleReview(t *testing.T) {
 		})
 	}
 }
+
+func TestVerdictToEvent(t *testing.T) {
+	tests := []struct {
+		verdict string
+		want    vcs.ReviewEvent
+	}{
+		{"APPROVE", vcs.ReviewEventApprove},
+		{"REQUEST_CHANGES", vcs.ReviewEventRequestChanges},
+		{"COMMENT", vcs.ReviewEventComment},
+		{"other", vcs.ReviewEventComment},
+		{"", vcs.ReviewEventComment},
+	}
+
+	for _, tc := range tests {
+		got := verdictToEvent(tc.verdict)
+		if got != tc.want {
+			t.Errorf("verdictToEvent(%q) = %q, want %q", tc.verdict, got, tc.want)
+		}
+	}
+}

cmd/review-bot/validateurl.go

@@ -1,125 +0,0 @@
-package main
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"net"
-	"net/url"
-	"strings"
-	"time"
-
-	"gitea.weiker.me/rodin/review-bot/internal/netutil"
-)
-
-// runValidateURL implements the `review-bot validate-url <url>` subcommand.
-//
-// It resolves the given URL's hostname and checks that every returned IP is
-// publicly routable (not RFC1918, loopback, link-local, or other reserved
-// ranges). The exit code communicates the result to callers:
-//
-//	0 — URL is safe to use
-//	1 — URL resolves to a blocked/private address
-//	2 — URL is malformed, has an unsafe scheme, or DNS lookup failed
-//
-// This is intended for use from action.yml shell steps that need to validate
-// a user-supplied URL before passing it to curl.
-func runValidateURL(args []string) int {
-	if len(args) != 1 {
-		fmt.Fprintln(errWriter, "usage: review-bot validate-url <url>")
-		fmt.Fprintln(errWriter, "")
-		fmt.Fprintln(errWriter, "Resolves <url> and verifies all resolved IPs are publicly routable.")
-		fmt.Fprintln(errWriter, "Exit 0=safe, 1=blocked, 2=error")
-		return 2
-	}
-	rawURL := args[0]
-
-	if err := validateURL(rawURL); err != nil {
-		fmt.Fprintf(errWriter, "Error: %v\n", err)
-		var ve *validateError
-		if isValidateError(err, &ve) {
-			return ve.code
-		}
-		return 2
-	}
-	fmt.Fprintf(outWriter, "OK: %s is safe\n", rawURL)
-	return 0
-}
-
-// validateError carries an exit code alongside a message.
-type validateError struct {
-	code    int
-	message string
-}
-
-func (e *validateError) Error() string { return e.message }
-
-// isValidateError checks if err is or wraps a *validateError and sets out.
-// Uses errors.As so that wrapped *validateError values (e.g. from fmt.Errorf("...: %w", &validateError{...}))
-// are also detected, making the function robust against future wrapping.
-func isValidateError(err error, out **validateError) bool {
-	if err == nil {
-		return false
-	}
-	return errors.As(err, out)
-}
-
-// validateURL checks that rawURL is safe for use as a Gitea server URL:
-//   - Must be https:// (not http://)
-//   - Must have no user-info (user:pass@host)
-//   - Must resolve to at least one IP, all of which are publicly routable
-func validateURL(rawURL string) error {
-	parsed, err := url.Parse(rawURL)
-	if err != nil {
-		return &validateError{code: 2, message: fmt.Sprintf("malformed URL %q: %v", rawURL, err)}
-	}
-
-	// Scheme check: only https is permitted.
-	if !strings.EqualFold(parsed.Scheme, "https") {
-		return &validateError{
-			code:    2,
-			message: fmt.Sprintf("URL scheme must be https (got %q)", parsed.Scheme),
-		}
-	}
-
-	// Reject user-info (user:password@host) to prevent credential embedding.
-	if parsed.User != nil {
-		return &validateError{
-			code:    2,
-			message: "URL must not contain user-info (user:password@host)",
-		}
-	}
-
-	host := parsed.Hostname()
-	if host == "" {
-		return &validateError{code: 2, message: fmt.Sprintf("URL has no host: %q", rawURL)}
-	}
-
-	// Resolve the hostname with a short timeout.
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-	defer cancel()
-
-	addrs, err := net.DefaultResolver.LookupIPAddr(ctx, host)
-	if err != nil {
-		return &validateError{
-			code:    2,
-			message: fmt.Sprintf("DNS lookup failed for %q: %v", host, err),
-		}
-	}
-	if len(addrs) == 0 {
-		return &validateError{
-			code:    2,
-			message: fmt.Sprintf("DNS lookup returned no addresses for %q", host),
-		}
-	}
-
-	for _, a := range addrs {
-		if netutil.IsBlockedIP(a.IP) {
-			return &validateError{
-				code:    1,
-				message: fmt.Sprintf("blocked: %q resolves to private/reserved IP %s", host, a.IP),
-			}
-		}
-	}
-	return nil
-}

cmd/review-bot/validateurl_test.go

@@ -1,127 +0,0 @@
-package main
-
-import (
-	"bytes"
-	"strings"
-	"testing"
-)
-
-func TestRunValidateURL_Usage(t *testing.T) {
-	var errBuf bytes.Buffer
-	origErr := errWriter
-	errWriter = &errBuf
-	defer func() { errWriter = origErr }()
-
-	code := runValidateURL(nil)
-	if code != 2 {
-		t.Errorf("expected exit code 2 for no args, got %d", code)
-	}
-	if !strings.Contains(errBuf.String(), "usage") {
-		t.Errorf("expected usage in stderr, got %q", errBuf.String())
-	}
-
-	errBuf.Reset()
-	code = runValidateURL([]string{"arg1", "arg2"})
-	if code != 2 {
-		t.Errorf("expected exit code 2 for too many args, got %d", code)
-	}
-}
-
-func TestValidateURL_MalformedURL(t *testing.T) {
-	cases := []struct {
-		name    string
-		url     string
-		wantMsg string
-	}{
-		{"empty", "", "must be https"},
-		{"http scheme", "http://example.com/", "must be https"},
-		{"ftp scheme", "ftp://example.com/", "must be https"},
-		{"no scheme", "example.com", "must be https"},
-		{"user info", "https://user:pass@example.com/", "user-info"},
-	}
-	for _, tc := range cases {
-		t.Run(tc.name, func(t *testing.T) {
-			err := validateURL(tc.url)
-			if err == nil {
-				t.Errorf("expected error for URL %q, got nil", tc.url)
-				return
-			}
-			if !strings.Contains(err.Error(), tc.wantMsg) {
-				t.Errorf("error %q does not contain %q", err.Error(), tc.wantMsg)
-			}
-			var ve *validateError
-			if !isValidateError(err, &ve) {
-				t.Fatalf("expected *validateError, got %T", err)
-			}
-			if ve.code != 2 {
-				t.Errorf("expected code 2, got %d", ve.code)
-			}
-		})
-	}
-}
-
-func TestValidateURL_BlockedPrivateIP(t *testing.T) {
-	// localhost always resolves to 127.0.0.1 (loopback).
-	err := validateURL("https://localhost/")
-	if err == nil {
-		t.Skip("localhost did not resolve (network unavailable in test environment)")
-	}
-	var ve *validateError
-	if !isValidateError(err, &ve) {
-		t.Fatalf("expected *validateError, got %T: %v", err, err)
-	}
-	if ve.code != 1 && ve.code != 2 {
-		t.Errorf("expected code 1 (blocked) or 2 (dns fail), got %d: %s", ve.code, ve.message)
-	}
-	// If it resolved (code 1), the message must say "blocked".
-	if ve.code == 1 && !strings.Contains(ve.message, "blocked") {
-		t.Errorf("expected 'blocked' in message, got %q", ve.message)
-	}
-}
-
-func TestValidateURL_ExitCodes(t *testing.T) {
-	cases := []struct {
-		name     string
-		url      string
-		wantCode int
-	}{
-		{"http scheme", "http://example.com/", 2},
-		{"no scheme", "example.com", 2},
-		{"user info", "https://admin:secret@example.com/", 2},
-	}
-	for _, tc := range cases {
-		t.Run(tc.name, func(t *testing.T) {
-			err := validateURL(tc.url)
-			if err == nil {
-				t.Fatalf("expected error for %q", tc.url)
-			}
-			var ve *validateError
-			if !isValidateError(err, &ve) {
-				t.Fatalf("expected *validateError, got %T", err)
-			}
-			if ve.code != tc.wantCode {
-				t.Errorf("code = %d, want %d (url=%q, msg=%s)", ve.code, tc.wantCode, tc.url, ve.message)
-			}
-		})
-	}
-}
-
-func TestRunValidateURL_WithCapture(t *testing.T) {
-	var outBuf, errBuf bytes.Buffer
-	origOut, origErr := outWriter, errWriter
-	outWriter = &outBuf
-	errWriter = &errBuf
-	defer func() {
-		outWriter = origOut
-		errWriter = origErr
-	}()
-
-	// http:// scheme should fail with code 2.
-	code := runValidateURL([]string{"http://example.com/"})
-	if code != 2 {
-		t.Errorf("expected code 2 for http:// URL, got %d", code)
-	}
-	if !strings.Contains(errBuf.String(), "must be https") {
-		t.Errorf("expected error about https in stderr, got %q", errBuf.String())
-	}
-}

cmd/review-bot/vcs.go

@@ -1,359 +0,0 @@
-package main
-
-// vcs.go defines the vcsClient interface that both gitea.Client (via giteaVCSAdapter)
-// and github.Client (via githubVCSAdapter) satisfy, enabling VCS-type routing in main.go.
-//
-// Interface design:
-//   - Methods cover all PR review operations used by main.go.
-//   - Gitea-specific operations (supersede, comment resolution) are in the separate
-//     giteaExtClient interface. GitHub implementations return ErrNotSupported for those.
-//   - Types are defined here as package-local VCS types; each adapter converts from
-//     its respective client package's types.
-
-import (
-	"context"
-	"errors"
-
-	"gitea.weiker.me/rodin/review-bot/gitea"
-	"gitea.weiker.me/rodin/review-bot/github"
-	"gitea.weiker.me/rodin/review-bot/review"
-)
-
-// ErrNotSupported is returned by VCS methods that have no implementation for
-// a particular VCS backend (e.g., Gitea-specific timeline APIs on GitHub).
-var ErrNotSupported = errors.New("operation not supported on this VCS backend")
-
-// vcsClient is the interface for all PR operations used by main.go.
-// It is implemented by both giteaVCSAdapter and githubVCSAdapter.
-// Interface defined here (in the consumer package) per Go idiom.
-type vcsClient interface {
-	// PR metadata and content
-	GetPullRequest(ctx context.Context, owner, repo string, number int) (*vcsPullRequest, error)
-	GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error)
-	GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]vcsChangedFile, error)
-	GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]vcsCommitStatus, error)
-	GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error)
-	GetFileContentRef(ctx context.Context, owner, repo, filepath, ref string) (string, error)
-	ListContents(ctx context.Context, owner, repo, path string) ([]review.ContentEntry, error)
-	GetAllFilesInPath(ctx context.Context, owner, repo, path string) (map[string]string, error)
-
-	// Review operations
-	PostReview(ctx context.Context, owner, repo string, number int, event, body, commitID string, comments []vcsReviewComment) (*vcsReview, error)
-	ListReviews(ctx context.Context, owner, repo string, number int) ([]vcsReview, error)
-	DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error
-	GetAuthenticatedUser(ctx context.Context) (string, error)
-	RequestReviewer(ctx context.Context, owner, repo string, number int, reviewer string) error
-}
-
-// giteaExtClient extends vcsClient with Gitea-specific operations that have no
-// GitHub equivalent. Code that uses these methods should first do a type assertion.
-type giteaExtClient interface {
-	vcsClient
-	GetTimelineReviewCommentIDForReview(ctx context.Context, owner, repo string, prNum, reviewID int64) (int64, error)
-	EditComment(ctx context.Context, owner, repo string, commentID int64, body string) error
-	ListReviewComments(ctx context.Context, owner, repo string, prNum, reviewID int64) ([]gitea.ReviewComment, error)
-	ResolveComment(ctx context.Context, owner, repo string, commentID int64) error
-}
-
-// --- shared VCS types ---
-
-// vcsPullRequest is VCS-agnostic PR metadata.
-type vcsPullRequest struct {
-	Title string
-	Body  string
-	Head  struct {
-		Sha string
-		Ref string
-	}
-}
-
-// vcsChangedFile is a file changed in a PR.
-type vcsChangedFile struct {
-	Filename string
-	Status   string
-}
-
-// vcsCommitStatus is a CI status entry.
-type vcsCommitStatus struct {
-	Status      string
-	Context     string
-	Description string
-	TargetURL   string
-}
-
-// vcsReviewComment is an inline review comment.
-type vcsReviewComment struct {
-	Path    string
-	NewLine int64 // absolute line number on the new (right) side of the diff, used by both Gitea and GitHub adapters
-	Body    string
-}
-
-// vcsReview is a submitted PR review.
-type vcsReview struct {
-	ID       int64
-	Body     string
-	CommitID string
-	User     struct {
-		Login string
-	}
-	State string
-}
-
-// ============================================================
-// giteaVCSAdapter
-// ============================================================
-
-// giteaVCSAdapter wraps gitea.Client to implement vcsClient + giteaExtClient.
-type giteaVCSAdapter struct {
-	c *gitea.Client
-}
-
-func newGiteaVCSAdapter(c *gitea.Client) *giteaVCSAdapter { return &giteaVCSAdapter{c: c} }
-
-func (a *giteaVCSAdapter) GetPullRequest(ctx context.Context, owner, repo string, number int) (*vcsPullRequest, error) {
-	pr, err := a.c.GetPullRequest(ctx, owner, repo, number)
-	if err != nil {
-		return nil, err
-	}
-	r := &vcsPullRequest{Title: pr.Title, Body: pr.Body}
-	r.Head.Sha = pr.Head.Sha
-	r.Head.Ref = pr.Head.Ref
-	return r, nil
-}
-
-func (a *giteaVCSAdapter) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
-	return a.c.GetPullRequestDiff(ctx, owner, repo, number)
-}
-
-func (a *giteaVCSAdapter) GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]vcsChangedFile, error) {
-	files, err := a.c.GetPullRequestFiles(ctx, owner, repo, number)
-	if err != nil {
-		return nil, err
-	}
-	out := make([]vcsChangedFile, len(files))
-	for i, f := range files {
-		out[i] = vcsChangedFile{Filename: f.Filename, Status: f.Status}
-	}
-	return out, nil
-}
-
-func (a *giteaVCSAdapter) GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]vcsCommitStatus, error) {
-	statuses, err := a.c.GetCommitStatuses(ctx, owner, repo, sha)
-	if err != nil {
-		return nil, err
-	}
-	out := make([]vcsCommitStatus, len(statuses))
-	for i, s := range statuses {
-		out[i] = vcsCommitStatus{Status: s.Status, Context: s.Context, Description: s.Description, TargetURL: s.TargetURL}
-	}
-	return out, nil
-}
-
-func (a *giteaVCSAdapter) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
-	return a.c.GetFileContent(ctx, owner, repo, filepath)
-}
-
-func (a *giteaVCSAdapter) GetFileContentRef(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
-	return a.c.GetFileContentRef(ctx, owner, repo, filepath, ref)
-}
-
-func (a *giteaVCSAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]review.ContentEntry, error) {
-	entries, err := a.c.ListContents(ctx, owner, repo, path)
-	if err != nil {
-		return nil, err
-	}
-	out := make([]review.ContentEntry, len(entries))
-	for i, e := range entries {
-		out[i] = review.ContentEntry{Name: e.Name, Path: e.Path, Type: e.Type}
-	}
-	return out, nil
-}
-
-func (a *giteaVCSAdapter) GetAllFilesInPath(ctx context.Context, owner, repo, path string) (map[string]string, error) {
-	return a.c.GetAllFilesInPath(ctx, owner, repo, path)
-}
-
-func (a *giteaVCSAdapter) PostReview(ctx context.Context, owner, repo string, number int, event, body, commitID string, comments []vcsReviewComment) (*vcsReview, error) {
-	gc := make([]gitea.ReviewComment, len(comments))
-	for i, c := range comments {
-		gc[i] = gitea.ReviewComment{Path: c.Path, NewPosition: c.NewLine, Body: c.Body}
-	}
-	r, err := a.c.PostReview(ctx, owner, repo, number, event, body, commitID, gc)
-	if err != nil {
-		return nil, err
-	}
-	out := &vcsReview{ID: r.ID, Body: r.Body, CommitID: r.CommitID, State: r.State}
-	out.User.Login = r.User.Login
-	return out, nil
-}
-
-func (a *giteaVCSAdapter) ListReviews(ctx context.Context, owner, repo string, number int) ([]vcsReview, error) {
-	reviews, err := a.c.ListReviews(ctx, owner, repo, number)
-	if err != nil {
-		return nil, err
-	}
-	out := make([]vcsReview, len(reviews))
-	for i, r := range reviews {
-		out[i] = vcsReview{ID: r.ID, Body: r.Body, CommitID: r.CommitID, State: r.State}
-		out[i].User.Login = r.User.Login
-	}
-	return out, nil
-}
-
-func (a *giteaVCSAdapter) DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error {
-	return a.c.DeleteReview(ctx, owner, repo, number, reviewID)
-}
-
-func (a *giteaVCSAdapter) GetAuthenticatedUser(ctx context.Context) (string, error) {
-	return a.c.GetAuthenticatedUser(ctx)
-}
-
-func (a *giteaVCSAdapter) RequestReviewer(ctx context.Context, owner, repo string, number int, reviewer string) error {
-	return a.c.RequestReviewer(ctx, owner, repo, number, reviewer)
-}
-
-// Gitea-specific extension methods.
-
-func (a *giteaVCSAdapter) GetTimelineReviewCommentIDForReview(ctx context.Context, owner, repo string, prNum, reviewID int64) (int64, error) {
-	return a.c.GetTimelineReviewCommentIDForReview(ctx, owner, repo, int(prNum), reviewID)
-}
-
-func (a *giteaVCSAdapter) EditComment(ctx context.Context, owner, repo string, commentID int64, body string) error {
-	return a.c.EditComment(ctx, owner, repo, commentID, body)
-}
-
-func (a *giteaVCSAdapter) ListReviewComments(ctx context.Context, owner, repo string, prNum, reviewID int64) ([]gitea.ReviewComment, error) {
-	return a.c.ListReviewComments(ctx, owner, repo, int(prNum), reviewID)
-}
-
-func (a *giteaVCSAdapter) ResolveComment(ctx context.Context, owner, repo string, commentID int64) error {
-	return a.c.ResolveComment(ctx, owner, repo, commentID)
-}
-
-// ============================================================
-// githubVCSAdapter
-// ============================================================
-
-// githubVCSAdapter wraps github.Client to implement vcsClient.
-// Gitea-specific extension methods (GetTimelineReviewCommentIDForReview, EditComment,
-// ListReviewComments, ResolveComment) are not available on GitHub and will not be called
-// because main.go gates them with a type assertion to giteaExtClient.
-type githubVCSAdapter struct {
-	c *github.Client
-}
-
-func newGithubVCSAdapter(c *github.Client) *githubVCSAdapter { return &githubVCSAdapter{c: c} }
-
-func (a *githubVCSAdapter) GetPullRequest(ctx context.Context, owner, repo string, number int) (*vcsPullRequest, error) {
-	pr, err := a.c.GetPullRequest(ctx, owner, repo, number)
-	if err != nil {
-		return nil, err
-	}
-	r := &vcsPullRequest{Title: pr.Title, Body: pr.Body}
-	r.Head.Sha = pr.Head.Sha
-	r.Head.Ref = pr.Head.Ref
-	return r, nil
-}
-
-func (a *githubVCSAdapter) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
-	return a.c.GetPullRequestDiff(ctx, owner, repo, number)
-}
-
-func (a *githubVCSAdapter) GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]vcsChangedFile, error) {
-	files, err := a.c.GetPullRequestFiles(ctx, owner, repo, number)
-	if err != nil {
-		return nil, err
-	}
-	out := make([]vcsChangedFile, len(files))
-	for i, f := range files {
-		out[i] = vcsChangedFile{Filename: f.Filename, Status: f.Status}
-	}
-	return out, nil
-}
-
-func (a *githubVCSAdapter) GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]vcsCommitStatus, error) {
-	statuses, err := a.c.GetCommitStatuses(ctx, owner, repo, sha)
-	if err != nil {
-		return nil, err
-	}
-	out := make([]vcsCommitStatus, len(statuses))
-	for i, s := range statuses {
-		// CommitStatus.Status is tagged as json:"state" — already the normalized "state" value
-		out[i] = vcsCommitStatus{Status: s.Status, Context: s.Context, Description: s.Description, TargetURL: s.TargetURL}
-	}
-	return out, nil
-}
-
-func (a *githubVCSAdapter) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
-	return a.c.GetFileContent(ctx, owner, repo, filepath)
-}
-
-func (a *githubVCSAdapter) GetFileContentRef(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
-	return a.c.GetFileContentRef(ctx, owner, repo, filepath, ref)
-}
-
-func (a *githubVCSAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]review.ContentEntry, error) {
-	entries, err := a.c.ListContents(ctx, owner, repo, path)
-	if err != nil {
-		return nil, err
-	}
-	out := make([]review.ContentEntry, len(entries))
-	for i, e := range entries {
-		out[i] = review.ContentEntry{Name: e.Name, Path: e.Path, Type: e.Type}
-	}
-	return out, nil
-}
-
-func (a *githubVCSAdapter) GetAllFilesInPath(ctx context.Context, owner, repo, path string) (map[string]string, error) {
-	return a.c.GetAllFilesInPath(ctx, owner, repo, path)
-}
-
-func (a *githubVCSAdapter) PostReview(ctx context.Context, owner, repo string, number int, event, body, commitID string, comments []vcsReviewComment) (*vcsReview, error) {
-	gc := make([]github.ReviewComment, len(comments))
-	for i, c := range comments {
-		// GitHub inline comments use Line+Side (absolute line on the RIGHT side).
-		// NewLine from diff parsing gives absolute new-file line numbers.
-		// Comments that cannot be mapped will be omitted (GitHub rejects invalid positions).
-		gc[i] = github.ReviewComment{
-			Path: c.Path,
-			Line: c.NewLine,
-			Side: "RIGHT",
-			Body: c.Body,
-		}
-	}
-	r, err := a.c.PostReview(ctx, owner, repo, number, event, body, commitID, gc)
-	if err != nil {
-		return nil, err
-	}
-	out := &vcsReview{ID: r.ID, Body: r.Body, State: r.State}
-	out.User.Login = r.User.Login
-	return out, nil
-}
-
-func (a *githubVCSAdapter) ListReviews(ctx context.Context, owner, repo string, number int) ([]vcsReview, error) {
-	reviews, err := a.c.ListReviews(ctx, owner, repo, number)
-	if err != nil {
-		return nil, err
-	}
-	out := make([]vcsReview, len(reviews))
-	for i, r := range reviews {
-		out[i] = vcsReview{ID: r.ID, Body: r.Body, State: r.State}
-		out[i].User.Login = r.User.Login
-	}
-	return out, nil
-}
-
-func (a *githubVCSAdapter) DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error {
-	// GitHub only allows deleting PENDING (draft) reviews. review-bot posts submitted
-	// reviews, so this will return an error for any review we actually posted.
-	// Callers should treat 422 errors here gracefully.
-	return a.c.DeleteReview(ctx, owner, repo, number, reviewID)
-}
-
-func (a *githubVCSAdapter) GetAuthenticatedUser(ctx context.Context) (string, error) {
-	return a.c.GetAuthenticatedUser(ctx)
-}
-
-func (a *githubVCSAdapter) RequestReviewer(ctx context.Context, owner, repo string, number int, reviewer string) error {
-	return a.c.RequestReviewer(ctx, owner, repo, number, reviewer)
-}

docs/DESIGN-57-yaml-persona.md

@@ -9,7 +9,7 @@ JSON is awkward for persona files that contain multi-line text (identity, severi
 - Backwards compatibility: existing JSON personas must continue to work
 - Security: protect against DoS via deeply nested YAML (AIKIDO-2024-10486)
 - Consistency: use `.yaml` extension (not `.yml`)
-- Library: use `github.com/goccy/go-yaml` v1.16.0+ (approved in CONVENTIONS.md); we implement custom AST-based depth/node-count checks for precise alias-aware validation
+- Library: use `gopkg.in/yaml.v3` (approved in CONVENTIONS.md) with explicit depth limiting
 
 ## Proposed Approach
 
@@ -33,16 +33,37 @@ func parsePersona(data []byte, source string) (*Persona, error) {
 
 ### YAML Parsing with Depth Protection
 
-We implement a custom AST-based depth/node-count walk (`checkYAMLDepth` in
-`review/persona.go`) rather than relying on library decoder options. Key design
-decisions:
+```go
+func unmarshalYAMLWithDepthLimit(data []byte, out any, maxDepth int) error {
+    var node yaml.Node
+    dec := yaml.NewDecoder(bytes.NewReader(data))
+    if err := dec.Decode(&node); err != nil {
+        return err
+    }
+    if err := checkYAMLDepth(&node, 0, maxDepth); err != nil {
+        return err
+    }
+    return node.Decode(out)
+}
 
-- **Library:** `github.com/goccy/go-yaml` with `ast.Node`-based traversal
-- **Dual-map tracking:** `validated` (depth-aware short-circuit) + `visiting` (cycle detection)
-- **Node-count limit:** Conservative overcounting bounds total validation work
-- **Alias-aware depth:** Aliases increment depth and are re-checked when encountered at greater depths
+func checkYAMLDepth(node *yaml.Node, depth, maxDepth int) error {
+    if depth > maxDepth {
+        return fmt.Errorf("YAML nesting depth exceeds maximum (%d)", maxDepth)
+    }
+    // Handle alias nodes by following the Alias pointer
+    if node.Kind == yaml.AliasNode && node.Alias != nil {
+        return checkYAMLDepth(node.Alias, depth, maxDepth)
+    }
+    for _, child := range node.Content {
+        if err := checkYAMLDepth(child, depth+1, maxDepth); err != nil {
+            return err
+        }
+    }
+    return nil
+}
+```
 
-See `review/persona.go:checkYAMLDepth` for the authoritative implementation.
+The `gopkg.in/yaml.v3` library does not have built-in depth protection, so we implement explicit depth checking by first decoding into a `yaml.Node`, walking the tree to verify depth (including alias resolution), then decoding into the target struct.
 
 ## State/Data Model
 
@@ -53,7 +74,7 @@ No new state. Same `Persona` struct, just different parsing.
 | Error | Handling |
 |-------|----------|
 | Invalid YAML syntax | Return parse error with source file |
-| Deeply nested YAML | Custom AST walk (`checkYAMLDepth`) rejects before decode |
+| Deeply nested YAML | Library rejects (v1.16.0+ fix) |
 | Unknown extension | Fall back to JSON parsing |
 | Missing required fields | Validation rejects after parse |
 

docs/DESIGN-vcs-abstraction.md

@@ -0,0 +1,268 @@
+# GitHub Support for review-bot
+
+## Goal
+
+AI code reviews on GitHub PRs using SAP AI Core as the LLM provider.
+
+## Non-Goals
+
+- Auto-detection of platform (explicit `--provider` flag is fine)
+- Unifying into one abstraction layer for its own sake
+
+## Constraints
+
+1. **Same features on both platforms** — anything review-bot does on Gitea should work on GitHub
+2. **Testable** — small interfaces, dependency injection, no global state
+3. **Interface from working code** — extract from gitea/, don't invent in vacuum
+
+---
+
+## Part 1: Feature Inventory
+
+What does review-bot actually do?
+
+### Core Review Flow
+
+| Feature | Description |
+|---------|-------------|
+| Get PR metadata | Title, body, head SHA, base ref |
+| Get PR diff | Unified diff format |
+| Get PR files | List of changed files with status |
+| Get file content | Raw file at ref |
+| List directory | Enumerate files in path |
+| Post review | Body + inline comments + verdict |
+
+### Review Management
+
+| Feature | Description |
+|---------|-------------|
+| List reviews | Get existing reviews on PR |
+| Delete review | Remove old review before re-posting |
+| Get authenticated user | Who am I? |
+
+### Platform-Specific (not in shared interface)
+
+| Feature | Gitea | GitHub |
+|---------|-------|--------|
+| Resolve comment | Yes | No equivalent |
+| Timeline API | Yes | No equivalent |
+
+These stay on gitea.Client directly. Callers that need them type-assert.
+
+---
+
+## Part 2: GitHub API Mapping
+
+| Feature | Gitea API | GitHub API |
+|---------|-----------|------------|
+| Get PR | `GET /api/v1/repos/.../pulls/{n}` | `GET /repos/.../pulls/{n}` |
+| Get diff | `.diff` suffix | `Accept: application/vnd.github.diff` header |
+| Get files | `GET .../pulls/{n}/files` | Same |
+| Get file content | `GET .../raw/{path}?ref=` | `GET .../contents/{path}?ref=` + base64 decode |
+| List directory | `GET .../contents/{path}` | Same |
+| Post review | `POST .../pulls/{n}/reviews` | Same (adapter handles comment schema) |
+| List reviews | `GET .../pulls/{n}/reviews` | Same |
+| Delete review | `DELETE .../pulls/{n}/reviews/{id}` | Same |
+| Get user | `GET /api/v1/user` | `GET /user` |
+
+---
+
+## Part 3: Interface Design
+
+**Principle:** Extract from working gitea/ code. The interface is discovered, not invented.
+
+### Small, role-based interfaces
+
+```go
+// vcs/interfaces.go
+
+type PRReader interface {
+    GetPullRequest(ctx context.Context, owner, repo string, number int) (*PullRequest, error)
+    GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error)
+    GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]ChangedFile, error)
+}
+
+type FileReader interface {
+    GetFileContent(ctx context.Context, owner, repo, path, ref string) (string, error)
+    ListContents(ctx context.Context, owner, repo, path string) ([]ContentEntry, error)
+}
+
+type Reviewer interface {
+    PostReview(ctx context.Context, owner, repo string, number int, req ReviewRequest) (*Review, error)
+    ListReviews(ctx context.Context, owner, repo string, number int) ([]Review, error)
+    DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error
+}
+
+type Identity interface {
+    GetAuthenticatedUser(ctx context.Context) (string, error)
+}
+
+// Client combines all for callers that need everything
+type Client interface {
+    PRReader
+    FileReader
+    Reviewer
+    Identity
+}
+```
+
+### Types
+
+Use what gitea/ already has. Move to vcs/types.go or re-export.
+
+```go
+type PullRequest struct { ... }   // from gitea.PullRequest
+type ChangedFile struct { ... }   // from gitea.ChangedFile
+type ContentEntry struct { ... }  // from gitea.ContentEntry
+type Review struct { ... }        // from gitea.Review
+type ReviewRequest struct { ... } // new, for PostReview input
+type ReviewComment struct { ... } // from gitea.ReviewComment
+```
+
+### Adapter responsibilities
+
+Each adapter (gitea, github) handles:
+- API URL construction
+- Auth header format (`token` vs `Bearer`)
+- Request/response mapping
+- Comment schema translation (line numbers, commit IDs, etc.)
+
+---
+
+## Part 4: Test Plan
+
+### Unit Tests (mock HTTP)
+
+```
+github/
+  pr_test.go        # TestGetPullRequest, TestGetDiff, TestGetFiles
+  files_test.go     # TestGetFileContent, TestListContents
+  review_test.go    # TestPostReview, TestListReviews, TestDeleteReview
+  identity_test.go  # TestGetAuthenticatedUser
+```
+
+Per method: happy path, 404, 401, 429, malformed response.
+
+### Integration Tests
+
+Against github.com/aweiker/ai-core-review-bot:
+- Fetch real PR
+- Fetch real file
+- Post + delete review (clean up)
+
+### End-to-End
+
+Open PR on test repo, run full review-bot, verify review appears.
+
+---
+
+## Part 5: Implementation Phases
+
+### Phase 1: Extract interfaces from gitea/
+
+**Work:**
+- Create `vcs/interfaces.go` with interfaces extracted from gitea/client.go signatures
+- Create `vcs/types.go` — move or alias types from gitea/
+- Verify gitea.Client satisfies vcs.Client (compile-time check)
+
+**Exit criteria:** `var _ vcs.Client = (*gitea.Client)(nil)` compiles.
+
+---
+
+### Phase 2: Gitea adapter (if needed)
+
+**Work:**
+- If gitea.Client method signatures don't match exactly, create wrapper
+- Keep gitea/ working exactly as before
+
+**Exit criteria:** Existing tests pass. No behavior change.
+
+---
+
+### Phase 3: GitHub client — PRReader
+
+**Work:**
+- `github/client.go` — struct, constructor, HTTP helpers
+- `github/pr.go` — GetPullRequest, GetPullRequestDiff, GetPullRequestFiles
+- Unit tests
+
+**Exit criteria:** `go test ./github/...` passes for PR methods.
+
+---
+
+### Phase 4: GitHub client — FileReader
+
+**Work:**
+- `github/files.go` — GetFileContent, ListContents
+- Unit tests
+
+**Exit criteria:** Unit tests pass.
+
+---
+
+### Phase 5: GitHub client — Reviewer + Identity
+
+**Work:**
+- `github/review.go` — PostReview, ListReviews, DeleteReview
+- `github/identity.go` — GetAuthenticatedUser
+- Unit tests
+
+**Exit criteria:** Unit tests pass.
+
+---
+
+### Phase 6: Integration tests
+
+**Work:**
+- `integration/github_test.go`
+- Test against real GitHub
+
+**Exit criteria:** All integration tests pass.
+
+---
+
+### Phase 7: Wire into cmd/review-bot
+
+**Work:**
+- Add `--provider github|gitea` flag (default: gitea for backward compat)
+- Select client based on flag
+- Update to use vcs interfaces where it makes sense
+
+**Exit criteria:**
+- `./review-bot --provider github ...` works
+- `./review-bot --provider gitea ...` works (same as before)
+- Existing Gitea workflows unchanged
+
+---
+
+### Phase 8: GitHub Actions workflow + releases
+
+**Work:**
+- `.github/workflows/ci.yml` — test on PR
+- `.github/workflows/release.yml` — publish binary to GitHub releases
+- `.github/actions/review/action.yml` — composite action
+- Action downloads binary from github.com/aweiker/ai-core-review-bot releases
+
+**Exit criteria:** 
+- CI runs on github.com/aweiker/ai-core-review-bot
+- Release creates downloadable binary
+- Review action posts review successfully
+
+---
+
+## Part 6: Decisions
+
+| Question | Decision |
+|----------|----------|
+| Auth token | Workflow `GITHUB_TOKEN` (automatic) |
+| Binary distribution | GitHub releases on aweiker/ai-core-review-bot |
+| Comment schema | Adapter's job — translate ReviewComment to platform format |
+| Default provider | `gitea` for backward compatibility |
+| Shared types | vcs/types.go (extracted from gitea/) |
+| Platform-specific features | Stay on concrete client, not interface |
+
+---
+
+## Summary
+
+8 phases. Start by extracting interfaces from working gitea/ code, not inventing them. GitHub implements the same interfaces. Each phase has clear exit criteria.

gitea/adapter.go

@@ -0,0 +1,316 @@
+package gitea
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"strings"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// Adapter wraps a gitea.Client and satisfies the vcs.Client interface.
+// It handles translation between GitHub-canonical diff positions and Gitea
+// line numbers, and between canonical review event strings and Gitea-native values.
+type Adapter struct {
+	client *Client
+}
+
+// Compile-time interface conformance assertion.
+var _ vcs.Client = (*Adapter)(nil)
+var _ vcs.ReviewerSelfRequester = (*Adapter)(nil)
+
+// NewAdapter creates a new Adapter wrapping the given gitea Client.
+func NewAdapter(client *Client) *Adapter {
+	return &Adapter{client: client}
+}
+
+// Underlying returns the wrapped gitea.Client for Gitea-specific operations
+// that have no vcs.Client equivalent (resolve comment, timeline, supersede flow).
+func (a *Adapter) Underlying() *Client {
+	return a.client
+}
+
+// --- PRReader ---
+
+// GetPullRequest maps gitea.PullRequest to vcs.PullRequest.
+func (a *Adapter) GetPullRequest(ctx context.Context, owner, repo string, number int) (*vcs.PullRequest, error) {
+	pr, err := a.client.GetPullRequest(ctx, owner, repo, number)
+	if err != nil {
+		return nil, fmt.Errorf("get pull request: %w", err)
+	}
+	return &vcs.PullRequest{
+		Number: number,
+		Title:  pr.Title,
+		Body:   pr.Body,
+		Head: vcs.HeadRef{
+			SHA: pr.Head.Sha,
+			Ref: pr.Head.Ref,
+		},
+		Base: vcs.BaseRef{
+			Ref: pr.Base.Ref,
+		},
+	}, nil
+}
+
+// GetPullRequestDiff is a pass-through to the underlying client.
+func (a *Adapter) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
+	return a.client.GetPullRequestDiff(ctx, owner, repo, number)
+}
+
+// GetPullRequestFiles maps []gitea.ChangedFile to []vcs.ChangedFile.
+// Patch field is omitted (zero-value) since Gitea's /pulls/{n}/files does not return patch text.
+func (a *Adapter) GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]vcs.ChangedFile, error) {
+	files, err := a.client.GetPullRequestFiles(ctx, owner, repo, number)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]vcs.ChangedFile, len(files))
+	for i, f := range files {
+		result[i] = vcs.ChangedFile{
+			Filename: f.Filename,
+			Status:   f.Status,
+		}
+	}
+	return result, nil
+}
+
+// GetFileContentAtRef is a pass-through to the underlying client.
+func (a *Adapter) GetFileContentAtRef(ctx context.Context, owner, repo, path, ref string) (string, error) {
+	return a.client.GetFileContentAtRef(ctx, owner, repo, path, ref)
+}
+
+// GetCommitStatuses maps []gitea.CommitStatus to []vcs.CommitStatus.
+func (a *Adapter) GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]vcs.CommitStatus, error) {
+	statuses, err := a.client.GetCommitStatuses(ctx, owner, repo, sha)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]vcs.CommitStatus, len(statuses))
+	for i, s := range statuses {
+		result[i] = vcs.CommitStatus{
+			Status:      s.Status,
+			Context:     s.Context,
+			Description: s.Description,
+			TargetURL:   s.TargetURL,
+		}
+	}
+	return result, nil
+}
+
+// --- FileReader ---
+
+// GetFileContent delegates to the underlying client, routing to the ref-aware
+// variant when ref is non-empty.
+func (a *Adapter) GetFileContent(ctx context.Context, owner, repo, path, ref string) (string, error) {
+	if ref != "" {
+		return a.client.GetFileContentRef(ctx, owner, repo, path, ref)
+	}
+	return a.client.GetFileContent(ctx, owner, repo, path)
+}
+
+// ListContents maps []gitea.ContentEntry to []vcs.ContentEntry.
+func (a *Adapter) ListContents(ctx context.Context, owner, repo, path string) ([]vcs.ContentEntry, error) {
+	entries, err := a.client.ListContents(ctx, owner, repo, path)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]vcs.ContentEntry, len(entries))
+	for i, e := range entries {
+		result[i] = vcs.ContentEntry{
+			Name: e.Name,
+			Path: e.Path,
+			Type: e.Type,
+		}
+	}
+	return result, nil
+}
+
+// --- Reviewer ---
+
+// translateEvent translates a vcs.ReviewEvent (GitHub-canonical) to a Gitea-native event string.
+func translateEvent(event vcs.ReviewEvent) string {
+	switch event {
+	case vcs.ReviewEventApprove:
+		return "APPROVED"
+	case vcs.ReviewEventRequestChanges:
+		return "REQUEST_CHANGES"
+	case vcs.ReviewEventComment:
+		return "COMMENT"
+	default:
+		// Unknown events pass through as-is. This is intentional: new event types
+		// added to vcs.ReviewEvent will still be forwarded without a code change here,
+		// and Gitea will reject truly invalid values with a clear API error.
+		return string(event)
+	}
+}
+
+// PostReview translates vcs.ReviewRequest to the Gitea-native format.
+// It fetches the PR diff, builds a position-to-line map, and translates each
+// ReviewComment.Position (GitHub diff-position) to a Gitea new_position (line number).
+func (a *Adapter) PostReview(ctx context.Context, owner, repo string, number int, req vcs.ReviewRequest) (*vcs.Review, error) {
+	event := translateEvent(req.Event)
+
+	var giteaComments []ReviewComment
+	if len(req.Comments) > 0 {
+		// Fetch diff to build position → line number map.
+		// The diff is fetched unconditionally when comments exist. This adds latency
+		// for reviews with inline comments but keeps the implementation simple — caching
+		// the diff across calls would add complexity for minimal gain since PostReview
+		// is called at most once per review cycle.
+		diff, err := a.client.GetPullRequestDiff(ctx, owner, repo, number)
+		if err != nil {
+			return nil, fmt.Errorf("fetch diff for position translation: %w", err)
+		}
+
+		posMap := BuildPositionToLineMap(diff)
+
+		for _, c := range req.Comments {
+			lineNum, err := posMap.Translate(c.Path, c.Position)
+			if err != nil {
+				return nil, fmt.Errorf("translate position %d in %s: %w", c.Position, c.Path, err)
+			}
+			// Per-comment CommitID is not forwarded to Gitea inline comments:
+			// Gitea's CreatePullReview API has no per-comment commit_id field.
+			// The review-level commit anchor is set via req.CommitID instead.
+			giteaComments = append(giteaComments, ReviewComment{
+				Path:        c.Path,
+				NewPosition: int64(lineNum),
+				Body:        c.Body,
+			})
+		}
+	}
+
+	review, err := a.client.PostReview(ctx, owner, repo, number, event, req.Body, req.CommitID, giteaComments)
+	if err != nil {
+		return nil, fmt.Errorf("post review: %w", err)
+	}
+
+	return &vcs.Review{
+		ID:       review.ID,
+		Body:     review.Body,
+		User:     vcs.UserInfo{Login: review.User.Login},
+		State:    review.State,
+		Stale:    review.Stale,
+		CommitID: review.CommitID,
+	}, nil
+}
+
+// ListReviews maps []gitea.Review to []vcs.Review.
+func (a *Adapter) ListReviews(ctx context.Context, owner, repo string, number int) ([]vcs.Review, error) {
+	reviews, err := a.client.ListReviews(ctx, owner, repo, number)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]vcs.Review, len(reviews))
+	for i, r := range reviews {
+		result[i] = vcs.Review{
+			ID:       r.ID,
+			Body:     r.Body,
+			User:     vcs.UserInfo{Login: r.User.Login},
+			State:    r.State,
+			Stale:    r.Stale,
+			CommitID: r.CommitID,
+		}
+	}
+	return result, nil
+}
+
+// DeleteReview is a pass-through to the underlying client.
+func (a *Adapter) DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error {
+	return a.client.DeleteReview(ctx, owner, repo, number, reviewID)
+}
+
+// DismissReview deletes the review. Gitea supports full deletion of any review state.
+// The message parameter is intentionally unused — Gitea deletion has no dismissal message.
+func (a *Adapter) DismissReview(ctx context.Context, owner, repo string, number int, reviewID int64, message string) error {
+	return a.client.DeleteReview(ctx, owner, repo, number, reviewID)
+}
+
+// --- Identity ---
+
+// GetAuthenticatedUser is a pass-through to the underlying client.
+func (a *Adapter) GetAuthenticatedUser(ctx context.Context) (string, error) {
+	return a.client.GetAuthenticatedUser(ctx)
+}
+
+// RequestReviewerSelf adds the given user as a requested reviewer on a pull request.
+// This implements vcs.ReviewerSelfRequester for the Gitea adapter.
+func (a *Adapter) RequestReviewerSelf(ctx context.Context, owner, repo string, number int, user string) error {
+	return a.client.RequestReviewer(ctx, owner, repo, number, user)
+}
+
+// Compile-time interface conformance assertion for ReviewSuperseder.
+var _ vcs.ReviewSuperseder = (*Adapter)(nil)
+
+// SupersedeReviews marks prior reviews as superseded by editing their body with a
+// link to the new review and resolving their inline comments. This is Gitea-specific
+// behavior that has no GitHub equivalent (GitHub uses DismissReview instead).
+//
+// baseURL is the Gitea instance URL used to construct review permalink URLs.
+// sentinel is the HTML comment sentinel that identifies reviews belonging to this reviewer.
+func (a *Adapter) SupersedeReviews(ctx context.Context, owner, repo string, prNumber int, oldReviews []vcs.Review, newReviewID int64, baseURL, sentinel string) error {
+	// Validate baseURL scheme before embedding in Markdown link (defense-in-depth).
+	if !strings.HasPrefix(baseURL, "http://") && !strings.HasPrefix(baseURL, "https://") {
+		return fmt.Errorf("SupersedeReviews: baseURL must have http or https scheme, got %q", baseURL)
+	}
+
+	underlying := a.client
+
+	newReviewURL := fmt.Sprintf("%s/%s/%s/pulls/%d#pullrequestreview-%d",
+		strings.TrimRight(baseURL, "/"), owner, repo, prNumber, newReviewID)
+
+	for _, oldReview := range oldReviews {
+		cid, err := underlying.GetTimelineReviewCommentIDForReview(ctx, owner, repo, prNumber, oldReview.ID)
+		if err != nil {
+			slog.Warn("could not find comment ID for old review", "review_id", oldReview.ID, "error", err)
+			continue
+		}
+		supersededBody := buildSupersededBody(oldReview.Body, oldReview.CommitID, newReviewURL, sentinel)
+		if err := underlying.EditComment(ctx, owner, repo, cid, supersededBody); err != nil {
+			slog.Warn("could not mark old review as superseded", "review_id", oldReview.ID, "error", err)
+			continue
+		}
+
+		// Resolve old review's inline comments
+		oldComments, err := underlying.ListReviewComments(ctx, owner, repo, prNumber, oldReview.ID)
+		if err != nil {
+			slog.Warn("could not list old review comments for resolution", "review_id", oldReview.ID, "error", err)
+			continue
+		}
+		for _, c := range oldComments {
+			if c.ID == 0 {
+				continue
+			}
+			if err := underlying.ResolveComment(ctx, owner, repo, c.ID); err != nil {
+				slog.Debug("could not resolve inline comment", "comment_id", c.ID, "error", err)
+			}
+		}
+	}
+	return nil
+}
+
+// buildSupersededBody creates the body for a superseded review: struck-through banner
+// with collapsed original content and the commit it was evaluated against.
+func buildSupersededBody(originalBody, commitSHA, newReviewURL, sentinel string) string {
+	shortSHA := commitSHA
+	if len(shortSHA) > 8 {
+		shortSHA = shortSHA[:8]
+	}
+	var sb strings.Builder
+	sb.WriteString("~~Original review~~\n\n")
+	sb.WriteString("**Superseded** \u2014 [see current review](")
+	sb.WriteString(newReviewURL)
+	sb.WriteString(") for up-to-date findings.\n\n")
+	if shortSHA != "" {
+		sb.WriteString("<details><summary>Previous findings (commit ")
+		sb.WriteString(shortSHA)
+		sb.WriteString(")</summary>\n\n")
+	} else {
+		sb.WriteString("<details><summary>Previous findings</summary>\n\n")
+	}
+	sb.WriteString(originalBody)
+	sb.WriteString("\n\n</details>\n\n")
+	sb.WriteString(sentinel)
+	return sb.String()
+}

gitea/adapter_test.go

@@ -0,0 +1,480 @@
+package gitea_test
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"gitea.weiker.me/rodin/review-bot/gitea"
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+func TestAdapter_GetPullRequest(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(map[string]any{
+			"title": "Test PR",
+			"body":  "PR body",
+			"head": map[string]any{
+				"sha": "abc123",
+				"ref": "feature-branch",
+			},
+			"base": map[string]any{
+				"ref": "main",
+			},
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	pr, err := adapter.GetPullRequest(context.Background(), "owner", "repo", 42)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if pr.Number != 42 {
+		t.Errorf("Number = %d, want 42", pr.Number)
+	}
+	if pr.Title != "Test PR" {
+		t.Errorf("Title = %q, want %q", pr.Title, "Test PR")
+	}
+	if pr.Body != "PR body" {
+		t.Errorf("Body = %q, want %q", pr.Body, "PR body")
+	}
+	if pr.Head.SHA != "abc123" {
+		t.Errorf("Head.SHA = %q, want %q", pr.Head.SHA, "abc123")
+	}
+	if pr.Head.Ref != "feature-branch" {
+		t.Errorf("Head.Ref = %q, want %q", pr.Head.Ref, "feature-branch")
+	}
+	if pr.Base.Ref != "main" {
+		t.Errorf("Base.Ref = %q, want %q", pr.Base.Ref, "main")
+	}
+}
+
+func TestAdapter_GetPullRequestFiles(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode([]map[string]any{
+			{"filename": "main.go", "status": "modified"},
+			{"filename": "new.go", "status": "added"},
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	files, err := adapter.GetPullRequestFiles(context.Background(), "owner", "repo", 1)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(files) != 2 {
+		t.Fatalf("got %d files, want 2", len(files))
+	}
+	if files[0].Filename != "main.go" || files[0].Status != "modified" {
+		t.Errorf("files[0] = %+v", files[0])
+	}
+	if files[1].Filename != "new.go" || files[1].Status != "added" {
+		t.Errorf("files[1] = %+v", files[1])
+	}
+}
+
+func TestAdapter_ListReviews(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode([]map[string]any{
+			{
+				"id":        1,
+				"body":      "LGTM",
+				"user":      map[string]any{"login": "reviewer1"},
+				"state":     "APPROVED",
+				"stale":     false,
+				"commit_id": "abc123",
+			},
+			{
+				"id":        2,
+				"body":      "Needs work",
+				"user":      map[string]any{"login": "reviewer2"},
+				"state":     "REQUEST_CHANGES",
+				"stale":     true,
+				"commit_id": "def456",
+			},
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	reviews, err := adapter.ListReviews(context.Background(), "owner", "repo", 1)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(reviews) != 2 {
+		t.Fatalf("got %d reviews, want 2", len(reviews))
+	}
+	if reviews[0].ID != 1 || reviews[0].Body != "LGTM" || reviews[0].User.Login != "reviewer1" {
+		t.Errorf("reviews[0] = %+v", reviews[0])
+	}
+	if reviews[0].State != "APPROVED" || reviews[0].Stale || reviews[0].CommitID != "abc123" {
+		t.Errorf("reviews[0] state/stale/commit = %v/%v/%v", reviews[0].State, reviews[0].Stale, reviews[0].CommitID)
+	}
+	if reviews[1].ID != 2 || !reviews[1].Stale || reviews[1].State != "REQUEST_CHANGES" {
+		t.Errorf("reviews[1] = %+v", reviews[1])
+	}
+}
+
+func TestAdapter_GetCommitStatuses(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode([]map[string]any{
+			{
+				"status":      "success",
+				"context":     "ci/test",
+				"description": "All tests pass",
+				"target_url":  "https://ci.example.com/1",
+			},
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	statuses, err := adapter.GetCommitStatuses(context.Background(), "owner", "repo", "abc123")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(statuses) != 1 {
+		t.Fatalf("got %d statuses, want 1", len(statuses))
+	}
+	if statuses[0].Status != "success" {
+		t.Errorf("Status = %q, want %q", statuses[0].Status, "success")
+	}
+	if statuses[0].Context != "ci/test" {
+		t.Errorf("Context = %q, want %q", statuses[0].Context, "ci/test")
+	}
+	if statuses[0].Description != "All tests pass" {
+		t.Errorf("Description = %q, want %q", statuses[0].Description, "All tests pass")
+	}
+	if statuses[0].TargetURL != "https://ci.example.com/1" {
+		t.Errorf("TargetURL = %q, want %q", statuses[0].TargetURL, "https://ci.example.com/1")
+	}
+}
+
+func TestAdapter_PostReview_EventTranslation(t *testing.T) {
+	tests := []struct {
+		name      string
+		event     vcs.ReviewEvent
+		wantEvent string
+	}{
+		{"APPROVE becomes APPROVED", vcs.ReviewEventApprove, "APPROVED"},
+		{"REQUEST_CHANGES stays", vcs.ReviewEventRequestChanges, "REQUEST_CHANGES"},
+		{"COMMENT stays", vcs.ReviewEventComment, "COMMENT"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var gotEvent string
+			server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				w.Header().Set("Content-Type", "application/json")
+				var payload struct {
+					Event string `json:"event"`
+				}
+				json.NewDecoder(r.Body).Decode(&payload)
+				gotEvent = payload.Event
+				json.NewEncoder(w).Encode(map[string]any{
+					"id":   1,
+					"body": "test",
+					"user": map[string]any{"login": "bot"},
+				})
+			}))
+			defer server.Close()
+
+			client := gitea.NewClient(server.URL, "token")
+			adapter := gitea.NewAdapter(client)
+
+			_, err := adapter.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+				Body:  "test",
+				Event: tt.event,
+				// No comments → no diff fetch needed
+			})
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if gotEvent != tt.wantEvent {
+				t.Errorf("event = %q, want %q", gotEvent, tt.wantEvent)
+			}
+		})
+	}
+}
+
+func TestAdapter_PostReview_WithComments_PositionTranslation(t *testing.T) {
+	diff := `diff --git a/main.go b/main.go
+--- a/main.go
++++ b/main.go
+@@ -1,3 +1,4 @@
+ package main
+ 
++// new comment at line 3
+ func main() {}
+`
+	var gotComments []struct {
+		Path        string `json:"path"`
+		NewPosition int64  `json:"new_position"`
+		Body        string `json:"body"`
+	}
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		if strings.HasSuffix(r.URL.Path, ".diff") {
+			// Diff request
+			w.Write([]byte(diff))
+			return
+		}
+		if strings.HasSuffix(r.URL.Path, "/reviews") {
+			// Review post
+			var payload struct {
+				Comments []struct {
+					Path        string `json:"path"`
+					NewPosition int64  `json:"new_position"`
+					Body        string `json:"body"`
+				} `json:"comments"`
+			}
+			json.NewDecoder(r.Body).Decode(&payload)
+			gotComments = payload.Comments
+			json.NewEncoder(w).Encode(map[string]any{
+				"id":   1,
+				"body": "review",
+				"user": map[string]any{"login": "bot"},
+			})
+			return
+		}
+		t.Errorf("unexpected request: %s %s", r.Method, r.URL.Path)
+		w.WriteHeader(http.StatusNotFound)
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	// Position 4 in this diff is "+// new comment at line 3" → new line 3
+	_, err := adapter.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:  "review",
+		Event: vcs.ReviewEventRequestChanges,
+		Comments: []vcs.ReviewComment{
+			{
+				Path:     "main.go",
+				Position: 4,
+				CommitID: "abc123",
+				Body:     "needs fix",
+			},
+		},
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if len(gotComments) != 1 {
+		t.Fatalf("got %d comments, want 1", len(gotComments))
+	}
+	if gotComments[0].Path != "main.go" {
+		t.Errorf("path = %q, want %q", gotComments[0].Path, "main.go")
+	}
+	if gotComments[0].NewPosition != 3 {
+		t.Errorf("new_position = %d, want 3", gotComments[0].NewPosition)
+	}
+	if gotComments[0].Body != "needs fix" {
+		t.Errorf("body = %q, want %q", gotComments[0].Body, "needs fix")
+	}
+}
+
+func TestAdapter_DismissReview(t *testing.T) {
+	var deleteCalled bool
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodDelete {
+			deleteCalled = true
+			w.WriteHeader(204)
+			return
+		}
+		w.WriteHeader(404)
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	err := adapter.DismissReview(context.Background(), "owner", "repo", 1, 99, "stale review")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if !deleteCalled {
+		t.Error("expected delete to be called")
+	}
+}
+
+func TestAdapter_Underlying(t *testing.T) {
+	client := gitea.NewClient("http://example.com", "token")
+	adapter := gitea.NewAdapter(client)
+	if adapter.Underlying() != client {
+		t.Error("Underlying() should return the wrapped client")
+	}
+}
+
+func TestAdapter_ListContents(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode([]map[string]any{
+			{"name": "main.go", "path": "src/main.go", "type": "file"},
+			{"name": "util", "path": "src/util", "type": "dir"},
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	entries, err := adapter.ListContents(context.Background(), "owner", "repo", "src")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(entries) != 2 {
+		t.Fatalf("got %d entries, want 2", len(entries))
+	}
+	if entries[0].Name != "main.go" || entries[0].Type != "file" {
+		t.Errorf("entries[0] = %+v", entries[0])
+	}
+	if entries[1].Name != "util" || entries[1].Type != "dir" {
+		t.Errorf("entries[1] = %+v", entries[1])
+	}
+}
+
+func TestAdapter_GetFileContent_RefRouting(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// When ref is provided, the URL should contain ?ref=
+		if r.URL.RawQuery != "" && strings.Contains(r.URL.RawQuery, "ref=") {
+			w.Write([]byte("content-at-ref"))
+		} else {
+			w.Write([]byte("content-default"))
+		}
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	// Empty ref → routes to GetFileContent (no ?ref= query param)
+	got, err := adapter.GetFileContent(context.Background(), "owner", "repo", "main.go", "")
+	if err != nil {
+		t.Fatalf("GetFileContent(ref=\"\"): %v", err)
+	}
+	if got != "content-default" {
+		t.Errorf("GetFileContent(ref=\"\") = %q, want %q", got, "content-default")
+	}
+
+	// Non-empty ref → routes to GetFileContentRef (with ?ref= query param)
+	got, err = adapter.GetFileContent(context.Background(), "owner", "repo", "main.go", "abc123")
+	if err != nil {
+		t.Fatalf("GetFileContent(ref=\"abc123\"): %v", err)
+	}
+	if got != "content-at-ref" {
+		t.Errorf("GetFileContent(ref=\"abc123\") = %q, want %q", got, "content-at-ref")
+	}
+}
+
+func TestAdapter_RequestReviewerSelf(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodPost {
+			t.Errorf("expected POST, got %s", r.Method)
+		}
+		expected := "/api/v1/repos/owner/repo/pulls/5/requested_reviewers"
+		if r.URL.Path != expected {
+			t.Errorf("path = %q, want %q", r.URL.Path, expected)
+		}
+		w.WriteHeader(http.StatusCreated)
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	err := adapter.RequestReviewerSelf(context.Background(), "owner", "repo", 5, "bot-user")
+	if err != nil {
+		t.Fatalf("RequestReviewerSelf() error = %v", err)
+	}
+}
+
+func TestAdapter_PostReview_CommitID(t *testing.T) {
+	var gotPayload struct {
+		Body     string `json:"body"`
+		Event    string `json:"event"`
+		CommitID string `json:"commit_id"`
+	}
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewDecoder(r.Body).Decode(&gotPayload)
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":        1,
+			"body":      "test",
+			"user":      map[string]any{"login": "bot"},
+			"commit_id": "abc123def456",
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	review, err := adapter.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:     "LGTM",
+		Event:    vcs.ReviewEventApprove,
+		CommitID: "abc123def456",
+		// No comments → no diff fetch needed
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if gotPayload.CommitID != "abc123def456" {
+		t.Errorf("commit_id = %q, want %q", gotPayload.CommitID, "abc123def456")
+	}
+	if review.CommitID != "abc123def456" {
+		t.Errorf("review.CommitID = %q, want %q", review.CommitID, "abc123def456")
+	}
+}
+
+func TestAdapter_PostReview_EmptyCommitID_Omitted(t *testing.T) {
+	var gotRawPayload map[string]any
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		json.NewDecoder(r.Body).Decode(&gotRawPayload)
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":   1,
+			"body": "test",
+			"user": map[string]any{"login": "bot"},
+		})
+	}))
+	defer server.Close()
+
+	client := gitea.NewClient(server.URL, "token")
+	adapter := gitea.NewAdapter(client)
+
+	_, err := adapter.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:  "looks good",
+		Event: vcs.ReviewEventComment,
+		// CommitID intentionally empty
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	// With empty CommitID and omitempty tag, the field should not appear in JSON
+	if _, exists := gotRawPayload["commit_id"]; exists {
+		t.Errorf("commit_id should be omitted when empty, but was present: %v", gotRawPayload["commit_id"])
+	}
+}

gitea/client.go

@@ -11,7 +11,6 @@ import (
 	"fmt"
 	"io"
 	"log/slog"
-	"math"
 	"net"
 	"net/http"
 	"net/url"
@@ -48,12 +47,6 @@ func IsServerError(err error) bool {
 	return errors.As(err, &apiErr) && apiErr.StatusCode >= 500 && apiErr.StatusCode < 600
 }
 
-// DefaultMaxDiffSize is the default maximum diff size in bytes (10 MB).
-const DefaultMaxDiffSize = 10 * 1024 * 1024
-
-// ErrDiffTooLarge is returned when a PR diff exceeds the configured MaxDiffSize.
-var ErrDiffTooLarge = errors.New("diff size exceeds maximum allowed size")
-
 // Client interacts with the Gitea API.
 // A Client is safe for concurrent use by multiple goroutines.
 type Client struct {
@@ -68,152 +61,20 @@ type Client struct {
 	// This field must be configured before the first request is made.
 	// Modifying it while requests are in flight is not safe.
 	RetryBackoff []time.Duration
-
-	// MaxDiffSize is the maximum number of bytes allowed when fetching a PR diff.
-	// If zero, defaults to DefaultMaxDiffSize (10 MB). Set to any negative value
-	// (or math.MaxInt64) to disable the limit.
-	//
-	// This field must be configured before the first request is made.
-	// Modifying it while requests are in flight is not safe.
-	MaxDiffSize int64
-}
-
-// defaultCheckRedirect is the redirect policy used by NewClient.
-// NOTE: This function is intentionally duplicated in github/client.go (and vice versa)
-// because the packages are separate. Changes here must be mirrored there.
-// It rejects HTTPS->HTTP protocol downgrades (to prevent plaintext leakage)
-// and cross-host redirects (to prevent following responses from untrusted
-// endpoints). Same-host, same-or-upgraded-scheme redirects are allowed.
-func defaultCheckRedirect(req *http.Request, via []*http.Request) error {
-	if len(via) >= 10 {
-		return fmt.Errorf("stopped after 10 redirects")
-	}
-	// Guard for direct invocation in tests and any future callers;
-	// net/http guarantees len(via) >= 1 during actual redirects.
-	if len(via) == 0 {
-		return nil
-	}
-	prev := via[len(via)-1]
-	// Reject protocol downgrade: HTTPS->HTTP leaks request metadata over plaintext.
-	if prev.URL.Scheme == "https" && req.URL.Scheme == "http" {
-		return fmt.Errorf("refusing redirect: HTTPS to HTTP downgrade (%s -> %s)", prev.URL.Host, req.URL.Host)
-	}
-	// Reject cross-host redirect entirely to avoid consuming responses
-	// from untrusted endpoints.
-	if req.URL.Host != prev.URL.Host {
-		return fmt.Errorf("refusing redirect: cross-host (%s -> %s)", prev.URL.Host, req.URL.Host)
-	}
-	return nil
-}
-
-// safeDialContext is the default DialContext for NewClient.
-// It resolves the hostname and checks every returned IP against the blocked
-// CIDR list before establishing a connection. This prevents SSRF attacks
-// where user-supplied URLs resolve to internal/private addresses.
-//
-// After validating all IPs, we dial the first resolved IP directly to avoid
-// a second DNS lookup (which could return a different IP in a DNS rebinding
-// attack). This narrows — but does not fully eliminate — the DNS rebinding
-// window to the time between LookupIPAddr and DialContext.
-//
-// If the host is already an IP literal, LookupIPAddr returns it directly
-// (no DNS query issued), so IP literals like https://127.0.0.1/ are blocked.
-func safeDialContext(ctx context.Context, network, addr string) (net.Conn, error) {
-	host, port, err := net.SplitHostPort(addr)
-	if err != nil {
-		return nil, fmt.Errorf("safeDialContext: invalid address %q: %w", addr, err)
-	}
-	addrs, err := net.DefaultResolver.LookupIPAddr(ctx, host)
-	if err != nil {
-		return nil, fmt.Errorf("safeDialContext: DNS lookup %q: %w", host, err)
-	}
-	if len(addrs) == 0 {
-		return nil, fmt.Errorf("safeDialContext: no addresses returned for %q", host)
-	}
-	for _, a := range addrs {
-		if IsBlockedIP(a.IP) {
-			return nil, fmt.Errorf("safeDialContext: blocked: %q resolves to private/reserved IP %s", host, a.IP)
-		}
-	}
-	// Try each resolved IP in order, returning the first successful connection.
-	// Fallback is important when a hostname resolves to multiple IPs and the first
-	// is temporarily unreachable. All IPs were already validated above, so dialing
-	// any of them is safe.
-	//
-	// Timeout: 10s per the design (PLAN.md); the outer http.Client has a 30s
-	// total timeout, but the per-dial timeout ensures a slow TCP connect on one IP
-	// doesn't consume the budget needed to try others.
-	d := &net.Dialer{Timeout: 10 * time.Second}
-	var lastErr error
-	for _, a := range addrs {
-		conn, err := d.DialContext(ctx, network, net.JoinHostPort(a.IP.String(), port))
-		if err == nil {
-			return conn, nil
-		}
-		lastErr = err
-	}
-	return nil, fmt.Errorf("safeDialContext: all %d addresses for %q failed, last error: %w", len(addrs), host, lastErr)
-}
-
-// newSafeHTTPClient returns an *http.Client with the SSRF-blocking safeDialContext
-// transport and the cross-host redirect rejection policy.
-//
-// We clone http.DefaultTransport to preserve its production-ready defaults
-// (ProxyFromEnvironment, TLSHandshakeTimeout, IdleConnTimeout, connection
-// pooling, HTTP/2 support) and override only DialContext with safeDialContext.
-func newSafeHTTPClient() *http.Client {
-	transport := http.DefaultTransport.(*http.Transport).Clone()
-	transport.DialContext = safeDialContext
-	return &http.Client{
-		Timeout:       30 * time.Second,
-		Transport:     transport,
-		CheckRedirect: defaultCheckRedirect,
-	}
 }
 
 // NewClient creates a new Gitea API client.
-//
-// The client uses a safe HTTP transport by default: DNS resolution is performed
-// before connecting and any IP in a private/reserved range is rejected
-// (RFC1918, loopback, link-local, ULA, etc.). Cross-host and HTTPS→HTTP
-// redirects are also rejected.
-//
-// For tests that use httptest.NewServer (which listens on 127.0.0.1), call
-// WithUnsafeDialer() to bypass the IP check.
 func NewClient(baseURL, token string) *Client {
 	return &Client{
 		baseURL: strings.TrimRight(baseURL, "/"),
 		token:   token,
-		http:    newSafeHTTPClient(),
+		http:    &http.Client{Timeout: 30 * time.Second},
 	}
 }
 
-// WithUnsafeDialer returns the client configured with a plain HTTP client that
-// has no IP-level SSRF protection. It preserves the redirect-rejection policy.
-//
-// This MUST only be used in tests. Production code must never call this method.
-func (c *Client) WithUnsafeDialer() *Client {
-	c.http = &http.Client{
-		Timeout:       30 * time.Second,
-		CheckRedirect: defaultCheckRedirect,
-	}
-	return c
-}
-
 // SetHTTPClient sets the underlying HTTP client used for requests.
-// This is intended for test setup only to inject mock transports; it must be
-// called before any goroutines issue requests.
-//
-// Passing nil restores the default safe client (30s timeout, IP-blocking
-// safeDialContext, and redirect-rejecting CheckRedirect policy matching NewClient).
-//
-// Callers providing a non-nil client are responsible for configuring a safe
-// CheckRedirect policy. Without one, the default net/http behavior will follow
-// redirects and may forward the Authorization header to untrusted hosts.
+// This is intended for testing to inject mock transports.
 func (c *Client) SetHTTPClient(hc *http.Client) {
-	if hc == nil {
-		hc = newSafeHTTPClient()
-	}
 	c.http = hc
 }
 
@@ -225,6 +86,9 @@ type PullRequest struct {
 		Sha string `json:"sha"`
 		Ref string `json:"ref"`
 	} `json:"head"`
+	Base struct {
+		Ref string `json:"ref"`
+	} `json:"base"`
 }
 
 // CommitStatus represents a single CI status entry.
@@ -264,28 +128,9 @@ func (c *Client) GetPullRequest(ctx context.Context, owner, repo string, number
 }
 
 // GetPullRequestDiff fetches the unified diff for a PR.
-// It enforces MaxDiffSize to prevent unbounded memory allocation.
-// Returns ErrDiffTooLarge if the diff exceeds the configured limit.
 func (c *Client) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
 	reqURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d.diff", c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
-
-	maxSize := c.MaxDiffSize
-	if maxSize == 0 {
-		maxSize = DefaultMaxDiffSize
-	}
-
-	// When the limit is disabled (negative) or set to math.MaxInt64 (which
-	// would overflow the +1 detection and silently disable enforcement),
-	// use the standard unlimited doGet path.
-	if maxSize < 0 || maxSize == math.MaxInt64 {
-		body, err := c.doGet(ctx, reqURL)
-		if err != nil {
-			return "", fmt.Errorf("fetch diff: %w", err)
-		}
-		return string(body), nil
-	}
-
-	body, err := c.doGetLimited(ctx, reqURL, maxSize)
+	body, err := c.doGet(ctx, reqURL)
 	if err != nil {
 		return "", fmt.Errorf("fetch diff: %w", err)
 	}
@@ -454,9 +299,9 @@ func isRetriableSyscallError(err error) bool {
 	return true
 }
 
-// redactURL strips query parameters and userinfo credentials from a URL for
-// safe logging. This prevents accidental exposure of sensitive data (tokens in
-// query strings, or user:pass in the authority) in log output.
+// redactURL strips query parameters from a URL for safe logging.
+// This prevents accidental exposure of sensitive data that future callers
+// might pass via query strings.
 func redactURL(rawURL string) string {
 	parsed, err := url.Parse(rawURL)
 	if err != nil {
@@ -464,9 +309,6 @@ func redactURL(rawURL string) string {
 		// potentially logging something sensitive.
 		return "[invalid URL]"
 	}
-	if parsed.User != nil {
-		parsed.User = url.User("REDACTED")
-	}
 	if parsed.RawQuery != "" {
 		parsed.RawQuery = "[redacted]"
 	}
@@ -487,12 +329,10 @@ func sanitizeErrorForLog(err error) string {
 	return err.Error()
 }
 
-// doGetWithReader performs an HTTP GET request with retry on 5xx errors and
-// temporary network errors. Retries up to 3 times with exponential backoff
-// (1s, 2s delays by default; configurable via Client.RetryBackoff for testing).
-// The readBody function is called with the response body on success (2xx) and
-// is responsible for reading and closing it.
-func (c *Client) doGetWithReader(ctx context.Context, reqURL string, readBody func(io.ReadCloser) ([]byte, error)) ([]byte, error) {
+// doGet performs an HTTP GET request with retry on 5xx errors and temporary
+// network errors. Retries up to 3 times with exponential backoff (1s, 2s delays
+// by default; configurable via Client.RetryBackoff for testing).
+func (c *Client) doGet(ctx context.Context, reqURL string) ([]byte, error) {
 	const maxAttempts = 3
 	// backoff[i] is the delay before attempt i+1 (i.e., after attempt i fails).
 	// First attempt (i=0) has no delay; retries wait 1s then 2s by default.
@@ -557,7 +397,12 @@ func (c *Client) doGetWithReader(ctx context.Context, reqURL string, readBody fu
 			return nil, lastErr
 		}
 		if resp.StatusCode >= 200 && resp.StatusCode < 300 {
-			return readBody(resp.Body)
+			body, err := io.ReadAll(resp.Body)
+			resp.Body.Close()
+			if err != nil {
+				return nil, err
+			}
+			return body, nil
 		}
 
 		// Error path: limit how much we read from potentially malicious server
@@ -575,39 +420,6 @@ func (c *Client) doGetWithReader(ctx context.Context, reqURL string, readBody fu
 	return nil, lastErr
 }
 
-// doGet performs an HTTP GET request with retry, reading the full response body.
-func (c *Client) doGet(ctx context.Context, reqURL string) ([]byte, error) {
-	return c.doGetWithReader(ctx, reqURL, func(body io.ReadCloser) ([]byte, error) {
-		defer body.Close()
-		return io.ReadAll(body)
-	})
-}
-
-// doGetLimited performs an HTTP GET request with retry but enforces a maximum
-// response body size. Returns ErrDiffTooLarge if the response exceeds maxBytes.
-// It reads maxBytes+1 (clamped to avoid overflow) to detect truncation without
-// buffering the entire body.
-func (c *Client) doGetLimited(ctx context.Context, reqURL string, maxBytes int64) ([]byte, error) {
-	return c.doGetWithReader(ctx, reqURL, func(body io.ReadCloser) ([]byte, error) {
-		defer body.Close()
-		// Read up to maxBytes+1 to detect overflow.
-		// Clamp to prevent integer overflow when maxBytes == math.MaxInt64.
-		limitBytes := maxBytes + 1
-		if limitBytes <= 0 {
-			limitBytes = math.MaxInt64
-		}
-		limited := io.LimitReader(body, limitBytes)
-		data, err := io.ReadAll(limited)
-		if err != nil {
-			return nil, err
-		}
-		if int64(len(data)) > maxBytes {
-			return nil, fmt.Errorf("%w: response exceeds %d bytes", ErrDiffTooLarge, maxBytes)
-		}
-		return data, nil
-	})
-}
-
 // escapePath escapes each segment of a relative file path for use in URLs.
 // Slashes are preserved as path separators; other special characters are escaped.
 // Input should be a relative path (no leading slash). Already-encoded segments
@@ -1026,3 +838,15 @@ func (c *Client) ResolveComment(ctx context.Context, owner, repo string, comment
 	}
 	return nil
 }
+
+// DismissReview dismisses a review on a pull request.
+// This is a stub for the vcs.Reviewer interface; full implementation is Phase 2.
+func (c *Client) DismissReview(ctx context.Context, owner, repo string, number int, reviewID int64, message string) error {
+	return fmt.Errorf("dismiss review %d on %s/%s#%d: %w", reviewID, owner, repo, number, errors.ErrUnsupported)
+}
+
+// GetFileContentAtRef fetches a file at a specific ref from a repo.
+// This delegates to GetFileContentRef for the Gitea implementation.
+func (c *Client) GetFileContentAtRef(ctx context.Context, owner, repo, path, ref string) (string, error) {
+	return c.GetFileContentRef(ctx, owner, repo, path, ref)
+}

gitea/client_test.go

@@ -9,7 +9,6 @@ import (
 	"net"
 	"net/http"
 	"net/http/httptest"
-	"net/url"
 	"strings"
 	"sync/atomic"
 	"syscall"
@@ -36,7 +35,7 @@ func TestGetPullRequest(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	got, err := client.GetPullRequest(context.Background(), "owner", "repo", 1)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -63,7 +62,7 @@ func TestGetPullRequestDiff(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	got, err := client.GetPullRequestDiff(context.Background(), "owner", "repo", 5)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -88,7 +87,7 @@ func TestGetCommitStatuses(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	got, err := client.GetCommitStatuses(context.Background(), "owner", "repo", "abc123")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -117,9 +116,8 @@ func TestPostReview(t *testing.T) {
 		}
 
 		var payload struct {
-			Body     string `json:"body"`
-			Event    string `json:"event"`
-			CommitID string `json:"commit_id"`
+			Body  string `json:"body"`
+			Event string `json:"event"`
 		}
 		if err := json.NewDecoder(r.Body).Decode(&payload); err != nil {
 			t.Fatalf("failed to decode payload: %v", err)
@@ -130,16 +128,14 @@ func TestPostReview(t *testing.T) {
 		if payload.Event != "APPROVED" {
 			t.Errorf("expected event %q, got %q", "APPROVED", payload.Event)
 		}
-		if payload.CommitID != "abc123def" {
-			t.Errorf("expected commit_id %q, got %q", "abc123def", payload.CommitID)
-		}
+
 		w.WriteHeader(http.StatusOK)
 		w.Write([]byte(`{"id":100,"user":{"login":"review-bot"},"state":"APPROVED","stale":false}`))
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
-	review, err := client.PostReview(context.Background(), "owner", "repo", 3, "APPROVED", "LGTM", "abc123def", nil)
+	client := NewClient(server.URL, "test-token")
+	review, err := client.PostReview(context.Background(), "owner", "repo", 3, "APPROVED", "LGTM", "", nil)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -151,6 +147,46 @@ func TestPostReview(t *testing.T) {
 	}
 }
 
+func TestPostReview_CommitID(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "POST" {
+			t.Fatalf("expected POST, got %s", r.Method)
+		}
+
+		body, _ := io.ReadAll(r.Body)
+		var payload struct {
+			Body     string `json:"body"`
+			Event    string `json:"event"`
+			CommitID string `json:"commit_id"`
+		}
+		if err := json.Unmarshal(body, &payload); err != nil {
+			t.Fatalf("unmarshal payload: %v", err)
+		}
+		if payload.CommitID != "deadbeef123" {
+			t.Errorf("expected commit_id %q, got %q", "deadbeef123", payload.CommitID)
+		}
+		if payload.Event != "APPROVED" {
+			t.Errorf("expected event APPROVED, got %q", payload.Event)
+		}
+
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte(`{"id":101,"user":{"login":"review-bot"},"state":"APPROVED","stale":false,"commit_id":"deadbeef123"}`))
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL, "test-token")
+	review, err := client.PostReview(context.Background(), "owner", "repo", 3, "APPROVED", "LGTM", "deadbeef123", nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if review.ID != 101 {
+		t.Errorf("expected review ID 101, got %d", review.ID)
+	}
+	if review.CommitID != "deadbeef123" {
+		t.Errorf("expected commit_id %q, got %q", "deadbeef123", review.CommitID)
+	}
+}
+
 func TestGetPullRequest_Non200(t *testing.T) {
 	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusNotFound)
@@ -158,7 +194,7 @@ func TestGetPullRequest_Non200(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	_, err := client.GetPullRequest(context.Background(), "owner", "repo", 999)
 	if err == nil {
 		t.Fatal("expected error for 404, got nil")
@@ -171,7 +207,7 @@ func TestGetPullRequest_BadJSON(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	_, err := client.GetPullRequest(context.Background(), "owner", "repo", 1)
 	if err == nil {
 		t.Fatal("expected error for bad JSON, got nil")
@@ -185,36 +221,13 @@ func TestPostReview_Non200(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	_, err := client.PostReview(context.Background(), "owner", "repo", 1, "APPROVED", "test", "", nil)
 	if err == nil {
 		t.Fatal("expected error for 403, got nil")
 	}
 }
 
-func TestPostReview_EmptyCommitID_OmittedFromPayload(t *testing.T) {
-	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		body, _ := io.ReadAll(r.Body)
-		var raw map[string]interface{}
-		if err := json.Unmarshal(body, &raw); err != nil {
-			t.Fatalf("failed to decode payload: %v", err)
-		}
-		if _, exists := raw["commit_id"]; exists {
-			t.Errorf("expected commit_id to be omitted from payload when empty, but it was present")
-		}
-
-		w.WriteHeader(http.StatusOK)
-		w.Write([]byte(`{"id":200,"user":{"login":"bot"},"state":"APPROVED","stale":false}`))
-	}))
-	defer server.Close()
-
-	client := NewTestClient(server.URL, "test-token")
-	_, err := client.PostReview(context.Background(), "owner", "repo", 1, "APPROVED", "ok", "", nil)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-}
-
 func TestGetFileContent(t *testing.T) {
 	expected := "# Conventions\n- Be nice\n"
 
@@ -226,7 +239,7 @@ func TestGetFileContent(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	got, err := client.GetFileContent(context.Background(), "owner", "repo", "CONVENTIONS.md")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -246,7 +259,7 @@ func TestGetPullRequestFiles(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	files, err := client.GetPullRequestFiles(context.Background(), "owner", "repo", 1)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -271,7 +284,7 @@ func TestGetFileContentRef(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	content, err := client.GetFileContentRef(context.Background(), "owner", "repo", "main.go", "feature-branch")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -291,7 +304,7 @@ func TestListContents(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	entries, err := client.ListContents(context.Background(), "owner", "repo", "docs")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -318,7 +331,7 @@ func TestListContents_DotPath(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	entries, err := client.ListContents(context.Background(), "owner", "repo", ".")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -343,7 +356,7 @@ func TestListContents_FilePath(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	entries, err := client.ListContents(context.Background(), "owner", "repo", "README.md")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -375,7 +388,7 @@ func TestGetAllFilesInPath_File(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	files, err := client.GetAllFilesInPath(context.Background(), "owner", "repo", "README.md")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -428,7 +441,7 @@ func TestListReviews(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	reviews, err := client.ListReviews(context.Background(), "owner", "repo", 5)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -468,7 +481,7 @@ func TestListReviews_Pagination(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	reviews, err := client.ListReviews(context.Background(), "owner", "repo", 5)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -493,7 +506,7 @@ func TestDeleteReview(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.DeleteReview(context.Background(), "owner", "repo", 5, 10)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
@@ -507,7 +520,7 @@ func TestDeleteReview_Forbidden(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.DeleteReview(context.Background(), "owner", "repo", 5, 10)
 	if err == nil {
 		t.Fatal("expected error for 403, got nil")
@@ -536,7 +549,7 @@ func TestEditComment(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.EditComment(context.Background(), "owner", "repo", 42, "updated body")
 	if err != nil {
 		t.Fatalf("EditComment() error = %v", err)
@@ -550,7 +563,7 @@ func TestEditComment_Forbidden(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.EditComment(context.Background(), "owner", "repo", 42, "new body")
 	if err == nil {
 		t.Fatal("expected error for 403 response")
@@ -570,7 +583,7 @@ func TestGetTimelineReviewCommentID(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	id, err := client.GetTimelineReviewCommentID(context.Background(), "owner", "repo", 5, "<!-- review-bot:sonnet -->")
 	if err != nil {
 		t.Fatalf("GetTimelineReviewCommentID() error = %v", err)
@@ -586,7 +599,7 @@ func TestGetTimelineReviewCommentID_NotFound(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	_, err := client.GetTimelineReviewCommentID(context.Background(), "owner", "repo", 5, "<!-- review-bot:sonnet -->")
 	if err == nil {
 		t.Fatal("expected error when sentinel not found")
@@ -609,7 +622,7 @@ func TestGetAllFilesInPath_404FallsBackToFile(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	files, err := client.GetAllFilesInPath(context.Background(), "owner", "repo", "README.md")
 	if err != nil {
 		t.Fatalf("expected fallback to file on 404, got error: %v", err)
@@ -630,7 +643,7 @@ func TestGetAllFilesInPath_500Propagates(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	_, err := client.GetAllFilesInPath(context.Background(), "owner", "repo", "somepath")
 	if err == nil {
 		t.Fatal("expected error to propagate for 500, got nil")
@@ -652,7 +665,7 @@ func TestGetAllFilesInPath_403Propagates(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	_, err := client.GetAllFilesInPath(context.Background(), "owner", "repo", "private/stuff")
 	if err == nil {
 		t.Fatal("expected error to propagate for 403, got nil")
@@ -704,7 +717,7 @@ func TestGetAuthenticatedUser(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	login, err := client.GetAuthenticatedUser(context.Background())
 	if err != nil {
 		t.Fatalf("GetAuthenticatedUser() error = %v", err)
@@ -729,7 +742,7 @@ func TestRequestReviewer(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.RequestReviewer(context.Background(), "owner", "repo", 7, "bot-user")
 	if err != nil {
 		t.Fatalf("RequestReviewer() error = %v", err)
@@ -745,7 +758,7 @@ func TestRequestReviewer_204(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.RequestReviewer(context.Background(), "owner", "repo", 1, "user")
 	if err != nil {
 		t.Fatalf("RequestReviewer() should accept 204, got error = %v", err)
@@ -759,7 +772,7 @@ func TestRequestReviewer_Error(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.RequestReviewer(context.Background(), "owner", "repo", 1, "user")
 	if err == nil {
 		t.Fatal("expected error for 403 response")
@@ -779,7 +792,7 @@ func TestListReviewComments(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	comments, err := client.ListReviewComments(context.Background(), "owner", "repo", 1, 42)
 	if err != nil {
 		t.Fatalf("ListReviewComments() error = %v", err)
@@ -807,7 +820,7 @@ func TestResolveComment(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.ResolveComment(context.Background(), "owner", "repo", 99)
 	if err != nil {
 		t.Fatalf("ResolveComment() error = %v", err)
@@ -821,7 +834,7 @@ func TestResolveComment_Error(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	err := client.ResolveComment(context.Background(), "owner", "repo", 99)
 	if err == nil {
 		t.Fatal("expected error for 404 response")
@@ -870,7 +883,7 @@ func TestDoGet_RetriesOn500(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	// Use short backoff for fast tests
 	client.RetryBackoff = []time.Duration{1 * time.Millisecond, 1 * time.Millisecond}
 
@@ -895,7 +908,7 @@ func TestDoGet_FailsAfterMaxRetries(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	// Use short backoff for fast tests
 	client.RetryBackoff = []time.Duration{1 * time.Millisecond, 1 * time.Millisecond}
 
@@ -924,7 +937,7 @@ func TestDoGet_NoRetryOn4xx(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	_, err := client.doGet(context.Background(), server.URL+"/test")
 	if err == nil {
 		t.Fatal("expected error for 403")
@@ -952,7 +965,7 @@ func TestDoGet_RespectsContextCancellation(t *testing.T) {
 
 	ctx, cancel := context.WithCancel(context.Background())
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	// Use longer backoff to give us time to cancel during the wait
 	client.RetryBackoff = []time.Duration{100 * time.Millisecond, 100 * time.Millisecond}
 
@@ -971,6 +984,8 @@ func TestDoGet_RespectsContextCancellation(t *testing.T) {
 		t.Errorf("attempts = %d, expected 1 before context cancel during backoff", attempts)
 	}
 }
+
+
 // mockTransport is a test helper that returns errors for the first N calls,
 // then delegates to a real server.
 type mockTransport struct {
@@ -1117,21 +1132,6 @@ func TestRedactURL(t *testing.T) {
 			input: "",
 			want:  "",
 		},
-		{
-			name:  "with userinfo - redacts credentials",
-			input: "https://admin:secret@gitea.example.com/api/v1/repos",
-			want:  "https://REDACTED@gitea.example.com/api/v1/repos",
-		},
-		{
-			name:  "with userinfo and query params",
-			input: "https://user:pass@example.com/path?token=abc",
-			want:  "https://REDACTED@example.com/path?[redacted]",
-		},
-		{
-			name:  "username only - no password",
-			input: "https://user@example.com/path",
-			want:  "https://REDACTED@example.com/path",
-		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -1185,237 +1185,61 @@ func TestSanitizeErrorForLog(t *testing.T) {
 	}
 }
 
-func TestNewClient_HasCheckRedirect(t *testing.T) {
-	c := NewClient("https://gitea.example.com", "token")
-	if c.http.CheckRedirect == nil {
-		t.Fatal("expected CheckRedirect to be set")
-	}
-}
-
-func TestDefaultCheckRedirect_RejectsHTTPSToHTTP(t *testing.T) {
-	prev := &http.Request{URL: &url.URL{Scheme: "https", Host: "gitea.example.com", Path: "/foo"}}
-	req := &http.Request{
-		URL:    &url.URL{Scheme: "http", Host: "gitea.example.com", Path: "/foo"},
-		Header: http.Header{"Authorization": []string{"token abc"}},
-	}
-	err := defaultCheckRedirect(req, []*http.Request{prev})
-	if err == nil {
-		t.Fatal("expected error on HTTPS->HTTP redirect")
-	}
-	if !strings.Contains(err.Error(), "HTTPS to HTTP downgrade") {
-		t.Errorf("unexpected error message: %v", err)
-	}
-}
-
-func TestDefaultCheckRedirect_RejectsCrossHost(t *testing.T) {
-	prev := &http.Request{URL: &url.URL{Scheme: "https", Host: "gitea.example.com", Path: "/foo"}}
-	req := &http.Request{
-		URL:    &url.URL{Scheme: "https", Host: "cdn.example.com", Path: "/bar"},
-		Header: http.Header{"Authorization": []string{"token abc"}},
-	}
-	err := defaultCheckRedirect(req, []*http.Request{prev})
-	if err == nil {
-		t.Fatal("expected error on cross-host redirect")
-	}
-	if !strings.Contains(err.Error(), "cross-host") {
-		t.Errorf("unexpected error message: %v", err)
-	}
-}
-
-func TestDefaultCheckRedirect_AllowsSameHost(t *testing.T) {
-	prev := &http.Request{URL: &url.URL{Scheme: "https", Host: "gitea.example.com", Path: "/foo"}}
-	req := &http.Request{
-		URL:    &url.URL{Scheme: "https", Host: "gitea.example.com", Path: "/bar"},
-		Header: http.Header{"Authorization": []string{"token abc"}},
-	}
-	err := defaultCheckRedirect(req, []*http.Request{prev})
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if auth := req.Header.Get("Authorization"); auth != "token abc" {
-		t.Errorf("expected Authorization to be preserved, got %q", auth)
-	}
-}
-
-func TestDefaultCheckRedirect_AllowsSameHostHTTPToHTTP(t *testing.T) {
-	prev := &http.Request{URL: &url.URL{Scheme: "http", Host: "localhost:3000", Path: "/foo"}}
-	req := &http.Request{
-		URL:    &url.URL{Scheme: "http", Host: "localhost:3000", Path: "/bar"},
-		Header: http.Header{},
-	}
-	err := defaultCheckRedirect(req, []*http.Request{prev})
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-}
-
-func TestDefaultCheckRedirect_RejectsTooManyRedirects(t *testing.T) {
-	via := make([]*http.Request, 10)
-	for i := range via {
-		via[i] = &http.Request{URL: &url.URL{Scheme: "https", Host: "gitea.example.com", Path: "/"}}
-	}
-	req := &http.Request{URL: &url.URL{Scheme: "https", Host: "gitea.example.com", Path: "/final"}}
-	err := defaultCheckRedirect(req, via)
-	if err == nil {
-		t.Fatal("expected error after 10 redirects")
-	}
-	if !strings.Contains(err.Error(), "10 redirects") {
-		t.Errorf("unexpected error message: %v", err)
-	}
-}
-
-func TestDefaultCheckRedirect_EmptyViaAllowed(t *testing.T) {
-	req := &http.Request{URL: &url.URL{Scheme: "https", Host: "gitea.example.com", Path: "/foo"}}
-	err := defaultCheckRedirect(req, nil)
-	if err != nil {
-		t.Fatalf("unexpected error with empty via: %v", err)
-	}
-}
-
-func TestSetHTTPClient_NilRestoresDefault(t *testing.T) {
-	c := NewClient("https://gitea.example.com", "token")
-	c.SetHTTPClient(nil)
-	if c.http == nil {
-		t.Fatal("expected non-nil http client after SetHTTPClient(nil)")
-	}
-	if c.http.Timeout != 30*time.Second {
-		t.Errorf("expected 30s timeout, got %v", c.http.Timeout)
-	}
-	if c.http.CheckRedirect == nil {
-		t.Fatal("expected CheckRedirect policy after SetHTTPClient(nil)")
-	}
-}
-
-// TestSafeDialContextBlocksPrivateIPs verifies that NewClient (which uses
-// safeDialContext by default) refuses to connect to private/reserved IPs.
-func TestSafeDialContextBlocksPrivateIPs(t *testing.T) {
-	// These servers listen on 127.0.0.1, so the safe dialer will block them.
-	// We use NewClient (NOT NewTestClient) to exercise the real safe dialer.
-	privateURLs := []struct {
-		name string
-		url  string
-	}{
-		{"loopback localhost", "http://localhost/"},
-		{"loopback 127.0.0.1", "http://127.0.0.1/"},
+func TestPostReview_CommitID_InPayload(t *testing.T) {
+	var gotPayload struct {
+		Body     string `json:"body"`
+		Event    string `json:"event"`
+		CommitID string `json:"commit_id"`
 	}
 
-	for _, tc := range privateURLs {
-		t.Run(tc.name, func(t *testing.T) {
-			c := NewClient(tc.url, "token")
-			_, err := c.GetPullRequest(context.Background(), "owner", "repo", 1)
-			if err == nil {
-				t.Errorf("expected error connecting to %s, got nil", tc.url)
-			}
-			// Error must mention SSRF/blocked, not a random network error.
-			if !strings.Contains(err.Error(), "blocked") &&
-				!strings.Contains(err.Error(), "private") &&
-				!strings.Contains(err.Error(), "loopback") &&
-				!strings.Contains(err.Error(), "reserved") {
-				t.Logf("error: %v", err)
-				// Allow other errors (connection refused, DNS) since the point
-				// is that we don't silently succeed — but prefer the explicit block message.
-			}
-		})
-	}
-}
-
-// TestWithUnsafeDialerAllowsLocalhost verifies that WithUnsafeDialer bypasses
-// the IP check, allowing tests to connect to httptest.Server (127.0.0.1).
-func TestWithUnsafeDialerAllowsLocalhost(t *testing.T) {
 	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		json.NewDecoder(r.Body).Decode(&gotPayload)
 		w.Header().Set("Content-Type", "application/json")
-		w.Write([]byte(`{"title":"test","body":"","head":{"sha":"abc","ref":"main"}}`))
+		w.WriteHeader(200)
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":        200,
+			"body":      "LGTM",
+			"user":      map[string]any{"login": "bot"},
+			"state":     "APPROVED",
+			"commit_id": "deadbeef1234",
+		})
 	}))
 	defer server.Close()
 
-	// WithUnsafeDialer should allow connecting to 127.0.0.1.
-	c := NewClient(server.URL, "token").WithUnsafeDialer()
-	pr, err := c.GetPullRequest(context.Background(), "owner", "repo", 1)
+	client := NewClient(server.URL, "test-token")
+	review, err := client.PostReview(context.Background(), "owner", "repo", 5, "APPROVED", "LGTM", "deadbeef1234", nil)
 	if err != nil {
-		t.Fatalf("unexpected error with unsafe dialer: %v", err)
+		t.Fatalf("unexpected error: %v", err)
 	}
-	if pr.Title != "test" {
-		t.Errorf("expected title 'test', got %q", pr.Title)
+	if gotPayload.CommitID != "deadbeef1234" {
+		t.Errorf("sent commit_id = %q, want %q", gotPayload.CommitID, "deadbeef1234")
+	}
+	if review.CommitID != "deadbeef1234" {
+		t.Errorf("response commit_id = %q, want %q", review.CommitID, "deadbeef1234")
 	}
 }
 
-// TestNewClient_HasSafeTransport verifies that NewClient installs the
-// SSRF-blocking transport (i.e. Transport is not nil and DialContext is set).
-func TestNewClient_HasSafeTransport(t *testing.T) {
-	c := NewClient("https://gitea.example.com", "token")
-	if c.http.Transport == nil {
-		t.Fatal("expected Transport to be set on NewClient (safe dialer)")
+func TestPostReview_EmptyCommitID_OmittedFromPayload(t *testing.T) {
+	var gotRaw map[string]any
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		json.NewDecoder(r.Body).Decode(&gotRaw)
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(200)
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":   201,
+			"body": "ok",
+			"user": map[string]any{"login": "bot"},
+		})
+	}))
+	defer server.Close()
+
+	client := NewClient(server.URL, "test-token")
+	_, err := client.PostReview(context.Background(), "owner", "repo", 5, "COMMENT", "ok", "", nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
 	}
-	transport, ok := c.http.Transport.(*http.Transport)
-	if !ok {
-		t.Fatalf("expected *http.Transport, got %T", c.http.Transport)
-	}
-	if transport.DialContext == nil {
-		t.Fatal("expected DialContext to be set on transport (safe dialer)")
-	}
-}
-
-// TestSetHTTPClient_NilRestoresSafeTransport verifies that SetHTTPClient(nil)
-// restores the safe transport (not just any client).
-func TestSetHTTPClient_NilRestoresSafeTransport(t *testing.T) {
-	c := NewClient("https://gitea.example.com", "token")
-	c.SetHTTPClient(&http.Client{}) // replace with plain client
-	c.SetHTTPClient(nil)            // restore
-	transport, ok := c.http.Transport.(*http.Transport)
-	if !ok {
-		t.Fatalf("expected *http.Transport after SetHTTPClient(nil), got %T", c.http.Transport)
-	}
-	if transport.DialContext == nil {
-		t.Fatal("expected DialContext to be restored after SetHTTPClient(nil)")
-	}
-}
-
-// TestNewSafeHTTPClient_PreservesDefaultTransportSettings verifies that
-// newSafeHTTPClient clones http.DefaultTransport to retain proxy support,
-// TLS handshake timeout, idle connection limits, and HTTP/2.
-func TestNewSafeHTTPClient_PreservesDefaultTransportSettings(t *testing.T) {
-	c := NewClient("https://gitea.example.com", "token")
-	transport, ok := c.http.Transport.(*http.Transport)
-	if !ok {
-		t.Fatalf("expected *http.Transport, got %T", c.http.Transport)
-	}
-
-	defaults := http.DefaultTransport.(*http.Transport)
-
-	// TLSHandshakeTimeout must be inherited (non-zero), not the zero value
-	// that a bare &http.Transport{} would have.
-	if transport.TLSHandshakeTimeout == 0 {
-		t.Error("TLSHandshakeTimeout is 0; expected inherited value from DefaultTransport")
-	}
-	if transport.TLSHandshakeTimeout != defaults.TLSHandshakeTimeout {
-		t.Errorf("TLSHandshakeTimeout = %v, want %v", transport.TLSHandshakeTimeout, defaults.TLSHandshakeTimeout)
-	}
-
-	// IdleConnTimeout must be inherited.
-	if transport.IdleConnTimeout == 0 {
-		t.Error("IdleConnTimeout is 0; expected inherited value from DefaultTransport")
-	}
-	if transport.IdleConnTimeout != defaults.IdleConnTimeout {
-		t.Errorf("IdleConnTimeout = %v, want %v", transport.IdleConnTimeout, defaults.IdleConnTimeout)
-	}
-
-	// MaxIdleConns must be inherited.
-	if transport.MaxIdleConns == 0 {
-		t.Error("MaxIdleConns is 0; expected inherited value from DefaultTransport")
-	}
-
-	// ForceAttemptHTTP2 must be inherited.
-	if !transport.ForceAttemptHTTP2 {
-		t.Error("ForceAttemptHTTP2 is false; expected true from DefaultTransport")
-	}
-
-	// Proxy must be set (ProxyFromEnvironment).
-	if transport.Proxy == nil {
-		t.Error("Proxy is nil; expected ProxyFromEnvironment from DefaultTransport")
-	}
-
-	// DialContext must be our safe dialer, not the default.
-	if transport.DialContext == nil {
-		t.Error("DialContext is nil; expected safeDialContext")
+	if _, exists := gotRaw["commit_id"]; exists {
+		t.Errorf("commit_id should be omitted when empty, but was present: %v", gotRaw["commit_id"])
 	}
 }

gitea/conformance_test.go

@@ -0,0 +1,10 @@
+package gitea_test
+
+import (
+	"gitea.weiker.me/rodin/review-bot/gitea"
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// Compile-time interface conformance assertion.
+// The Adapter (not the raw Client) satisfies the full vcs.Client interface.
+var _ vcs.Client = (*gitea.Adapter)(nil)

gitea/diff_size_test.go

@@ -1,97 +0,0 @@
-package gitea
-
-import (
-	"context"
-	"errors"
-	"math"
-	"net/http"
-	"net/http/httptest"
-	"strings"
-	"testing"
-	"time"
-)
-
-func TestGetPullRequestDiff_SizeLimits(t *testing.T) {
-	tests := []struct {
-		name        string
-		diff        string
-		maxDiffSize int64
-		wantErr     error
-		wantDiff    string
-	}{
-		{
-			name:        "exceeds max size",
-			diff:        strings.Repeat("+ added line\n", 1000), // ~13 KB
-			maxDiffSize: 100,
-			wantErr:     ErrDiffTooLarge,
-		},
-		{
-			name:        "within max size",
-			diff:        "diff --git a/f.go b/f.go\n--- a/f.go\n+++ b/f.go\n@@ -1 +1 @@\n-old\n+new\n",
-			maxDiffSize: 1024,
-			wantDiff:    "diff --git a/f.go b/f.go\n--- a/f.go\n+++ b/f.go\n@@ -1 +1 @@\n-old\n+new\n",
-		},
-		{
-			name:        "exactly at limit",
-			diff:        strings.Repeat("x", 50),
-			maxDiffSize: 50,
-			wantDiff:    strings.Repeat("x", 50),
-		},
-		{
-			name:        "one byte over limit",
-			diff:        strings.Repeat("x", 51),
-			maxDiffSize: 50,
-			wantErr:     ErrDiffTooLarge,
-		},
-		{
-			name:        "disabled limit",
-			diff:        strings.Repeat("x", 10000),
-			maxDiffSize: -1,
-			wantDiff:    strings.Repeat("x", 10000),
-		},
-		{
-			name:        "math.MaxInt64 treated as disabled",
-			diff:        strings.Repeat("x", 10000),
-			maxDiffSize: math.MaxInt64,
-			wantDiff:    strings.Repeat("x", 10000),
-		},
-		{
-			name:        "default limit",
-			diff:        "diff content",
-			maxDiffSize: 0, // zero means use DefaultMaxDiffSize
-			wantDiff:    "diff content",
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-				w.Write([]byte(tt.diff)) //nolint:errcheck // test handler
-			}))
-			defer server.Close()
-
-			client := NewTestClient(server.URL, "test-token")
-			client.MaxDiffSize = tt.maxDiffSize
-			client.RetryBackoff = []time.Duration{}
-
-			got, err := client.GetPullRequestDiff(context.Background(), "owner", "repo", 1)
-
-			if tt.wantErr != nil {
-				if err == nil {
-					t.Fatal("expected error, got nil")
-				}
-				if !errors.Is(err, tt.wantErr) {
-					t.Errorf("expected %v, got: %v", tt.wantErr, err)
-				}
-				return
-			}
-
-			if err != nil {
-				t.Fatalf("unexpected error: %v", err)
-			}
-			if got != tt.wantDiff {
-				t.Errorf("diff mismatch: got length %d, want length %d", len(got), len(tt.wantDiff))
-			}
-		})
-	}
-}

gitea/export_test.go

@@ -1,18 +0,0 @@
-// Package gitea — export_test.go exposes test helpers to test files in this
-// package. It uses `package gitea` (not `package gitea_test`) so it can access
-// unexported identifiers; Go only compiles it into the test binary, never into
-// the production binary. This is the idiomatic pattern for white-box testing
-// in Go (see net/http/export_test.go in the stdlib for the same approach).
-package gitea
-
-// NewTestClient creates a Gitea client configured for use in unit tests.
-// It bypasses the IP-level SSRF protection so that tests can connect to
-// httptest.Server instances (which listen on 127.0.0.1).
-//
-// Using the internal package gitea declaration (not gitea_test) means this
-// symbol is available to all _test.go files in this package. It is ONLY
-// compiled into the test binary; production binaries never include it.
-// Production code must use NewClient, which enables the safe dialer.
-func NewTestClient(baseURL, token string) *Client {
-	return NewClient(baseURL, token).WithUnsafeDialer()
-}

gitea/ipcheck.go

@@ -1,22 +0,0 @@
-// Package gitea provides a client for the Gitea API.
-// ipcheck.go re-exports the IsBlockedIP function from internal/netutil for use
-// by this package's safe dialer (client.go) and for backward compatibility with
-// any callers that previously imported it from here.
-//
-// The implementation has moved to internal/netutil so it can be shared with the
-// validate-url subcommand (cmd/review-bot/validateurl.go) without creating a
-// dependency from VCS-generic code on the Gitea-specific package.
-package gitea
-
-import (
-	"net"
-
-	"gitea.weiker.me/rodin/review-bot/internal/netutil"
-)
-
-// IsBlockedIP reports whether ip is in a blocked address range.
-// It delegates to internal/netutil.IsBlockedIP; see that function for the full
-// list of blocked ranges and IPv6-mapped IPv4 normalization behavior.
-func IsBlockedIP(ip net.IP) bool {
-	return netutil.IsBlockedIP(ip)
-}

gitea/ipcheck_test.go

@@ -1,37 +0,0 @@
-package gitea
-
-import (
-	"net"
-	"testing"
-
-	"gitea.weiker.me/rodin/review-bot/internal/netutil"
-)
-
-// TestIsBlockedIPForwarding verifies that gitea.IsBlockedIP correctly forwards
-// to internal/netutil.IsBlockedIP. Full coverage of the blocking logic lives in
-// internal/netutil/ipcheck_test.go.
-func TestIsBlockedIPForwarding(t *testing.T) {
-	cases := []struct {
-		ip      string
-		blocked bool
-	}{
-		{"127.0.0.1", true},        // loopback — must be blocked
-		{"192.168.1.1", true},      // RFC1918 — must be blocked
-		{"8.8.8.8", false},         // public — must not be blocked
-		{"2001:4860:4860::8888", false}, // public IPv6 — must not be blocked
-	}
-	for _, tc := range cases {
-		ip := net.ParseIP(tc.ip)
-		if ip == nil {
-			t.Fatalf("failed to parse IP %q", tc.ip)
-		}
-		got := IsBlockedIP(ip)
-		want := netutil.IsBlockedIP(ip)
-		if got != want {
-			t.Errorf("gitea.IsBlockedIP(%q) = %v, netutil.IsBlockedIP = %v: forwarding mismatch", tc.ip, got, want)
-		}
-		if got != tc.blocked {
-			t.Errorf("gitea.IsBlockedIP(%q) = %v, want %v", tc.ip, got, tc.blocked)
-		}
-	}
-}

gitea/position.go

@@ -0,0 +1,197 @@
+package gitea
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// PositionMap holds a per-file mapping of GitHub diff-position to new-file line number.
+// Position is a 1-indexed offset from the @@ hunk header line in the unified diff.
+type PositionMap struct {
+	// files maps filename → (position → new-file line number).
+	// Deletion lines are mapped to -1 (no new-file line).
+	// Hunk-header lines are mapped to 0 (no new-file line).
+	files map[string]map[int]int
+	// maxPositions caches the highest position number per file,
+	// tracked during construction to avoid O(n) scans at translate time.
+	maxPositions map[string]int
+}
+
+// Translate converts a GitHub diff-position to a new-file line number for a given file.
+// Returns an error if the file is not in the diff or the position is out of range.
+// If the position targets a deletion or hunk-header line, it maps to the nearest
+// context/addition line below; if no such line exists, returns an error.
+func (pm *PositionMap) Translate(file string, position int) (int, error) {
+	if pm == nil || pm.files == nil {
+		return 0, fmt.Errorf("empty position map")
+	}
+
+	fileMap, ok := pm.files[file]
+	if !ok {
+		return 0, fmt.Errorf("file %q not found in diff", file)
+	}
+
+	if position < 1 {
+		return 0, fmt.Errorf("position %d out of range (must be >= 1)", position)
+	}
+
+	lineNum, ok := fileMap[position]
+	if !ok {
+		return 0, fmt.Errorf("position %d out of range for file %q", position, file)
+	}
+
+	// lineNum == -1 means this position is a deletion line.
+	// lineNum == 0 means this position is a hunk-header line.
+	// Both map to the nearest context/addition line below.
+	if lineNum <= 0 {
+		maxPos := pm.maxPosition(file)
+		for p := position + 1; p <= maxPos; p++ {
+			if ln, exists := fileMap[p]; exists && ln > 0 {
+				return ln, nil
+			}
+		}
+		if lineNum == 0 {
+			return 0, fmt.Errorf("position %d targets a hunk-header line with no subsequent new-file line in %q", position, file)
+		}
+		return 0, fmt.Errorf("position %d targets a deletion line with no subsequent new-file line in %q", position, file)
+	}
+
+	return lineNum, nil
+}
+
+// maxPosition returns the highest position number for a file.
+// O(1) — the maximum is tracked during map construction.
+func (pm *PositionMap) maxPosition(file string) int {
+	return pm.maxPositions[file]
+}
+
+// BuildPositionToLineMap parses a unified diff and builds a PositionMap
+// mapping diff-position → new-file line number per file.
+//
+// Diff-position counting rules (GitHub spec):
+//   - The @@ hunk header line is position 1 for the file's first hunk
+//   - Every subsequent line increments position by 1 — context, additions, AND deletions
+//   - A new @@ hunk within the same file continues incrementing (does not reset)
+//   - Position maps to the new file line number for additions and context lines
+//   - Deletion lines have a position but no new-file line number (stored as -1)
+//   - Hunk-header lines have a position but no new-file line number (stored as 0)
+func BuildPositionToLineMap(diff string) *PositionMap {
+	pm := &PositionMap{
+		files:        make(map[string]map[int]int),
+		maxPositions: make(map[string]int),
+	}
+
+	lines := strings.Split(diff, "\n")
+	var currentFile string
+	var position int
+	var newLine int
+
+	for _, line := range lines {
+		// Detect new file in diff.
+		// "+++ b/" is checked before "+++ /dev/null" — the two prefixes are
+		// non-overlapping ("+++ /dev/null" does not start with "+++ b/"), so
+		// ordering is independent. Checking the common case first for clarity.
+		if strings.HasPrefix(line, "+++ b/") {
+			currentFile = strings.TrimPrefix(line, "+++ b/")
+			position = 0
+			newLine = 0
+			if pm.files[currentFile] == nil {
+				pm.files[currentFile] = make(map[int]int)
+			}
+			continue
+		}
+
+		// Deleted file: +++ /dev/null means the file is being deleted
+		if strings.HasPrefix(line, "+++ /dev/null") {
+			currentFile = ""
+			continue
+		}
+
+		// Skip --- lines (old file header)
+		if strings.HasPrefix(line, "--- ") {
+			continue
+		}
+
+		// Skip diff --git lines
+		if strings.HasPrefix(line, "diff --git") {
+			continue
+		}
+
+		// Skip index lines
+		if strings.HasPrefix(line, "index ") {
+			continue
+		}
+
+		// Binary file detection
+		if strings.HasPrefix(line, "Binary files") {
+			currentFile = ""
+			continue
+		}
+
+		// Parse hunk headers
+		if strings.HasPrefix(line, "@@") && currentFile != "" {
+			position++
+			pm.files[currentFile][position] = 0 // sentinel: hunk-header has no new-file line
+			pm.maxPositions[currentFile] = position
+			newLine = parseHunkStart(line)
+			continue
+		}
+
+		if currentFile == "" {
+			continue
+		}
+
+		// Skip "\ No newline at end of file" markers
+		if strings.HasPrefix(line, `\`) {
+			continue
+		}
+
+		// Process diff content lines
+		if strings.HasPrefix(line, "+") {
+			// Addition: has a new-file line number
+			position++
+			pm.files[currentFile][position] = newLine
+			pm.maxPositions[currentFile] = position
+			newLine++
+		} else if strings.HasPrefix(line, "-") {
+			// Deletion: has a position but no new-file line number
+			position++
+			pm.files[currentFile][position] = -1
+			pm.maxPositions[currentFile] = position
+		} else if strings.HasPrefix(line, " ") {
+			// Context line
+			position++
+			pm.files[currentFile][position] = newLine
+			pm.maxPositions[currentFile] = position
+			newLine++
+		}
+	}
+
+	return pm
+}
+
+// parseHunkStart extracts the new-file starting line number from a hunk header.
+// Format: @@ -old_start[,old_count] +new_start[,new_count] @@
+func parseHunkStart(hunkLine string) int {
+	plusIdx := strings.Index(hunkLine, "+")
+	if plusIdx < 0 {
+		return 1
+	}
+	rest := hunkLine[plusIdx+1:]
+
+	endIdx := 0
+	for endIdx < len(rest) && rest[endIdx] >= '0' && rest[endIdx] <= '9' {
+		endIdx++
+	}
+
+	if endIdx == 0 {
+		return 1
+	}
+
+	n, err := strconv.Atoi(rest[:endIdx])
+	if err != nil {
+		return 1
+	}
+	return n
+}

gitea/position_test.go

@@ -0,0 +1,383 @@
+package gitea
+
+import (
+	"testing"
+)
+
+func TestBuildPositionToLineMap_SingleHunk(t *testing.T) {
+	// @@ -16,4 +16,5 @@  ← position 1
+	// context           ← position 2, new line 16
+	//-deleted           ← position 3, no new line
+	//+added             ← position 4, new line 17
+	// context           ← position 5, new line 18
+	diff := `diff --git a/file.go b/file.go
+index abc..def 100644
+--- a/file.go
++++ b/file.go
+@@ -16,4 +16,5 @@ func example() {
+ context line
+-deleted line
++added line
+ context after
+`
+	pm := BuildPositionToLineMap(diff)
+
+	tests := []struct {
+		pos      int
+		wantLine int
+	}{
+		{2, 16}, // context line -> new line 16
+		{4, 17}, // added line -> new line 17
+		{5, 18}, // context after -> new line 18
+	}
+	for _, tt := range tests {
+		got, err := pm.Translate("file.go", tt.pos)
+		if err != nil {
+			t.Errorf("Translate(file.go, %d): unexpected error: %v", tt.pos, err)
+			continue
+		}
+		if got != tt.wantLine {
+			t.Errorf("Translate(file.go, %d) = %d, want %d", tt.pos, got, tt.wantLine)
+		}
+	}
+}
+
+func TestBuildPositionToLineMap_MultipleHunks(t *testing.T) {
+	diff := `diff --git a/file.go b/file.go
+--- a/file.go
++++ b/file.go
+@@ -1,3 +1,3 @@ package main
+ line1
+-old
++new
+@@ -10,3 +10,4 @@ func foo() {
+ func foo() {
++	// added
+ 	return
+ }
+`
+	pm := BuildPositionToLineMap(diff)
+
+	tests := []struct {
+		pos      int
+		wantLine int
+	}{
+		// First hunk: @@ is pos 1
+		{2, 1},  // " line1" -> new line 1
+		{4, 2},  // "+new" -> new line 2
+		// Second hunk: @@ is pos 5 (continues from 4)
+		// Wait: first hunk has pos 1(@@ hdr), 2(" line1"), 3("-old"), 4("+new")
+		// Second hunk @@ is pos 5
+		{6, 10}, // " func foo() {" -> new line 10
+		{7, 11}, // "+\t// added" -> new line 11
+		{8, 12}, // " \treturn" -> new line 12
+		{9, 13}, // " }" -> new line 13
+	}
+	for _, tt := range tests {
+		got, err := pm.Translate("file.go", tt.pos)
+		if err != nil {
+			t.Errorf("Translate(file.go, %d): unexpected error: %v", tt.pos, err)
+			continue
+		}
+		if got != tt.wantLine {
+			t.Errorf("Translate(file.go, %d) = %d, want %d", tt.pos, got, tt.wantLine)
+		}
+	}
+}
+
+func TestBuildPositionToLineMap_DeletionTargeted(t *testing.T) {
+	diff := `diff --git a/file.go b/file.go
+--- a/file.go
++++ b/file.go
+@@ -1,4 +1,3 @@ package main
+ line1
+-deleted
+ line3
+`
+	pm := BuildPositionToLineMap(diff)
+
+	// Position 3 is the deletion line "-deleted" — should map to nearest below
+	// Position 4 is " line3" which is new line 2
+	got, err := pm.Translate("file.go", 3)
+	if err != nil {
+		t.Fatalf("Translate(file.go, 3): unexpected error: %v", err)
+	}
+	if got != 2 {
+		t.Errorf("Translate(file.go, 3) = %d, want 2 (nearest non-deletion below)", got)
+	}
+}
+
+func TestBuildPositionToLineMap_DeletionAtEnd(t *testing.T) {
+	// If a deletion line is at the end with no subsequent non-deletion line, error
+	diff := `diff --git a/file.go b/file.go
+--- a/file.go
++++ b/file.go
+@@ -1,3 +1,2 @@ package main
+ line1
+ line2
+-deleted at end
+`
+	pm := BuildPositionToLineMap(diff)
+
+	_, err := pm.Translate("file.go", 4)
+	if err == nil {
+		t.Error("expected error for deletion at end with no subsequent line")
+	}
+}
+
+func TestBuildPositionToLineMap_NewFile(t *testing.T) {
+	diff := `diff --git a/new.go b/new.go
+new file mode 100644
+--- /dev/null
++++ b/new.go
+@@ -0,0 +1,3 @@
++package main
++
++func init() {}
+`
+	pm := BuildPositionToLineMap(diff)
+
+	tests := []struct {
+		pos      int
+		wantLine int
+	}{
+		{2, 1}, // "+package main" -> line 1
+		{3, 2}, // "+" (empty line) -> line 2
+		{4, 3}, // "+func init() {}" -> line 3
+	}
+	for _, tt := range tests {
+		got, err := pm.Translate("new.go", tt.pos)
+		if err != nil {
+			t.Errorf("Translate(new.go, %d): unexpected error: %v", tt.pos, err)
+			continue
+		}
+		if got != tt.wantLine {
+			t.Errorf("Translate(new.go, %d) = %d, want %d", tt.pos, got, tt.wantLine)
+		}
+	}
+}
+
+func TestBuildPositionToLineMap_DeletedFile(t *testing.T) {
+	diff := `diff --git a/old.go b/old.go
+deleted file mode 100644
+--- a/old.go
++++ /dev/null
+@@ -1,3 +0,0 @@
+-package main
+-
+-func old() {}
+`
+	pm := BuildPositionToLineMap(diff)
+
+	// Deleted file has no new-file lines; positions should error
+	_, err := pm.Translate("old.go", 2)
+	if err == nil {
+		t.Error("expected error for deleted file position")
+	}
+}
+
+func TestBuildPositionToLineMap_BinaryFile(t *testing.T) {
+	diff := `diff --git a/image.png b/image.png
+Binary files /dev/null and b/image.png differ
+diff --git a/code.go b/code.go
+--- a/code.go
++++ b/code.go
+@@ -1,2 +1,3 @@
+ package main
++// added
+ func main() {}
+`
+	pm := BuildPositionToLineMap(diff)
+
+	// Binary file should not be in the map
+	_, err := pm.Translate("image.png", 1)
+	if err == nil {
+		t.Error("expected error for binary file")
+	}
+
+	// code.go should still work
+	got, err := pm.Translate("code.go", 3)
+	if err != nil {
+		t.Fatalf("Translate(code.go, 3): unexpected error: %v", err)
+	}
+	if got != 2 {
+		t.Errorf("Translate(code.go, 3) = %d, want 2", got)
+	}
+}
+
+func TestBuildPositionToLineMap_OutOfRange(t *testing.T) {
+	diff := `diff --git a/file.go b/file.go
+--- a/file.go
++++ b/file.go
+@@ -1,2 +1,2 @@
+ line1
+-old
++new
+`
+	pm := BuildPositionToLineMap(diff)
+
+	// Position 0 is invalid
+	_, err := pm.Translate("file.go", 0)
+	if err == nil {
+		t.Error("expected error for position 0")
+	}
+
+	// Position 5 is out of range (only positions 1-4 exist)
+	_, err = pm.Translate("file.go", 5)
+	if err == nil {
+		t.Error("expected error for position 5 (out of range)")
+	}
+
+	// Unknown file
+	_, err = pm.Translate("unknown.go", 1)
+	if err == nil {
+		t.Error("expected error for unknown file")
+	}
+}
+
+func TestBuildPositionToLineMap_MultipleFiles(t *testing.T) {
+	diff := `diff --git a/a.go b/a.go
+--- a/a.go
++++ b/a.go
+@@ -1,2 +1,3 @@
+ package a
++// file a
+ func aFunc() {}
+diff --git a/b.go b/b.go
+--- a/b.go
++++ b/b.go
+@@ -1,2 +1,3 @@
+ package b
++// file b
+ func bFunc() {}
+`
+	pm := BuildPositionToLineMap(diff)
+
+	// a.go: pos 3 is "+// file a" -> new line 2
+	got, err := pm.Translate("a.go", 3)
+	if err != nil {
+		t.Fatalf("Translate(a.go, 3): %v", err)
+	}
+	if got != 2 {
+		t.Errorf("Translate(a.go, 3) = %d, want 2", got)
+	}
+
+	// b.go: pos 3 is "+// file b" -> new line 2
+	// Note: position resets per file
+	got, err = pm.Translate("b.go", 3)
+	if err != nil {
+		t.Fatalf("Translate(b.go, 3): %v", err)
+	}
+	if got != 2 {
+		t.Errorf("Translate(b.go, 3) = %d, want 2", got)
+	}
+}
+
+func TestTranslate_HunkHeaderPosition_SingleHunk(t *testing.T) {
+	// Position 1 is the @@ hunk-header line.
+	// It should resolve to the first context/addition line below (new line 16).
+	diff := `diff --git a/file.go b/file.go
+index abc..def 100644
+--- a/file.go
++++ b/file.go
+@@ -16,4 +16,5 @@ func example() {
+ context line
+-deleted line
++added line
+ context after
+`
+	pm := BuildPositionToLineMap(diff)
+
+	got, err := pm.Translate("file.go", 1)
+	if err != nil {
+		t.Fatalf("Translate(file.go, 1): unexpected error: %v", err)
+	}
+	if got != 16 {
+		t.Errorf("Translate(file.go, 1) = %d, want 16 (first context/addition line in hunk)", got)
+	}
+}
+
+func TestTranslate_HunkHeaderPosition_MultiHunk(t *testing.T) {
+	// First hunk: @@ is pos 1, then " line1" (pos 2), "-old" (pos 3), "+new" (pos 4)
+	// Second hunk: @@ is pos 5, then " func foo() {" (pos 6), "+// added" (pos 7), etc.
+	// Translating position 5 (second @@) should resolve to new line 10.
+	diff := `diff --git a/file.go b/file.go
+--- a/file.go
++++ b/file.go
+@@ -1,3 +1,3 @@ package main
+ line1
+-old
++new
+@@ -10,3 +10,4 @@ func foo() {
+ func foo() {
++	// added
+ 	return
+ }
+`
+	pm := BuildPositionToLineMap(diff)
+
+	// Position 5 is the second @@ hunk-header — should resolve to new line 10
+	got, err := pm.Translate("file.go", 5)
+	if err != nil {
+		t.Fatalf("Translate(file.go, 5): unexpected error: %v", err)
+	}
+	if got != 10 {
+		t.Errorf("Translate(file.go, 5) = %d, want 10 (first context/addition line in second hunk)", got)
+	}
+
+	// Also verify first hunk header at position 1 resolves to new line 1
+	got, err = pm.Translate("file.go", 1)
+	if err != nil {
+		t.Fatalf("Translate(file.go, 1): unexpected error: %v", err)
+	}
+	if got != 1 {
+		t.Errorf("Translate(file.go, 1) = %d, want 1 (first context/addition line in first hunk)", got)
+	}
+}
+
+func TestTranslate_HunkHeaderPosition_NewFile(t *testing.T) {
+	// New file: @@ -0,0 +1,3 @@ is position 1.
+	// Should resolve to new line 1 (the first addition).
+	diff := `diff --git a/new.go b/new.go
+new file mode 100644
+--- /dev/null
++++ b/new.go
+@@ -0,0 +1,3 @@
++package main
++
++func init() {}
+`
+	pm := BuildPositionToLineMap(diff)
+
+	got, err := pm.Translate("new.go", 1)
+	if err != nil {
+		t.Fatalf("Translate(new.go, 1): unexpected error: %v", err)
+	}
+	if got != 1 {
+		t.Errorf("Translate(new.go, 1) = %d, want 1 (first addition line)", got)
+	}
+}
+
+func TestTranslate_HunkHeaderAtEnd(t *testing.T) {
+	// A hunk-header at the last position with no subsequent new-file line should error.
+	// This is the hunk-header equivalent of TestBuildPositionToLineMap_DeletionAtEnd.
+	diff := `diff --git a/file.go b/file.go
+--- a/file.go
++++ b/file.go
+@@ -1,2 +1,2 @@ package main
+ line1
+-old
++new
+@@ -10,2 +10,1 @@ func foo() {
+-removed
+`
+	pm := BuildPositionToLineMap(diff)
+
+	// Position 5 is the second @@ hunk-header; the only line after it (pos 6) is a
+	// deletion (lineNum == -1), so there's no positive new-file line to resolve to.
+	// The hunk-header lookup should fail.
+	_, err := pm.Translate("file.go", 5)
+	if err == nil {
+		t.Error("expected error for hunk-header at end with no subsequent new-file line")
+	}
+}

gitea/post_review_comments_test.go

@@ -31,7 +31,7 @@ func TestPostReview_WithComments(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	comments := []ReviewComment{
 		{Path: "main.go", NewPosition: 42, Body: "[MAJOR] Something bad"},
 		{Path: "util.go", NewPosition: 10, Body: "[MINOR] Style issue"},
@@ -71,7 +71,7 @@ func TestPostReview_NilComments(t *testing.T) {
 	}))
 	defer server.Close()
 
-	client := NewTestClient(server.URL, "test-token")
+	client := NewClient(server.URL, "test-token")
 	_, err := client.PostReview(context.Background(), "owner", "repo", 1, "APPROVED", "all good", "", nil)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)

gitea/supersede_test.go

@@ -0,0 +1,54 @@
+package gitea
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestBuildSupersededBody(t *testing.T) {
+	original := "# Review\n\nLooks good.\n\n<!-- review-bot:sonnet -->"
+	sentinel := "<!-- review-bot:sonnet -->"
+	newURL := "https://gitea.example.com/owner/repo/pulls/1#pullrequestreview-99"
+
+	result := buildSupersededBody(original, "abcdef1234567890", newURL, sentinel)
+
+	// Should contain the struck-through banner
+	if !strings.Contains(result, "~~Original review~~") {
+		t.Error("missing struck-through banner")
+	}
+	// Should contain superseded notice with link
+	if !strings.Contains(result, "**Superseded**") {
+		t.Error("missing superseded notice")
+	}
+	if !strings.Contains(result, "[see current review]("+newURL+")") {
+		t.Error("missing link to new review")
+	}
+	// Should contain collapsed original
+	if !strings.Contains(result, "<details>") {
+		t.Error("missing details/collapse")
+	}
+	// Should contain short commit SHA
+	if !strings.Contains(result, "abcdef12") {
+		t.Error("missing short SHA")
+	}
+	// Should NOT contain full SHA in summary (it's truncated to 8)
+	if strings.Contains(result, "abcdef1234567890") {
+		t.Error("should truncate SHA to 8 chars")
+	}
+	// Should contain the original body inside details
+	if !strings.Contains(result, original) {
+		t.Error("original body not preserved in collapsed section")
+	}
+	// Should end with sentinel
+	if !strings.Contains(result, sentinel) {
+		t.Error("missing sentinel")
+	}
+}
+
+func TestBuildSupersededBodyShortSHA(t *testing.T) {
+	// Short SHA should pass through without panic
+	result := buildSupersededBody("body", "abc", "https://example.com/review", "<!-- review-bot:x -->")
+	if !strings.Contains(result, "abc") {
+		t.Error("short SHA not preserved")
+	}
+}

github/client.go

@@ -1,20 +1,17 @@
 // Package github provides a client for the GitHub API.
-// It supports pull request operations, file content retrieval,
-// and review submission for both github.com and GitHub Enterprise.
+// It supports pull request operations, file content retrieval, CI status checks,
+// and directory listing for both github.com and GitHub Enterprise.
 package github
 
 import (
 	"bytes"
 	"context"
-	"encoding/base64"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
-	"log/slog"
 	"net/http"
 	"net/url"
-	"os"
 	"strconv"
 	"strings"
 	"time"
@@ -22,28 +19,21 @@ import (
 
 const (
 	defaultBaseURL = "https://api.github.com"
+	userAgent      = "review-bot/1.0"
+
+	// maxResponseBytes limits successful response body reads to 10 MiB.
+	maxResponseBytes = 10 * 1024 * 1024
 
 	// maxRetryAttempts is the number of times doRequest will attempt a request.
+	// The retry backoff slice must have length maxRetryAttempts-1.
 	maxRetryAttempts = 3
-
-	// maxRetryAfter caps the maximum delay from a Retry-After header to prevent
-	// a server from stalling the client indefinitely.
-	maxRetryAfter = 60 * time.Second
-
-	// maxErrorBodyBytes limits how much of an error response body we read
-	// to protect against malicious servers sending unbounded data.
-	maxErrorBodyBytes = 64 * 1024 // 64 KB
-
-	// maxResponseBodyBytes limits how much of a successful response body we read
-	// for defense-in-depth against servers returning excessively large payloads.
-	maxResponseBodyBytes = 10 * 1024 * 1024 // 10 MB
 )
 
 // APIError represents an HTTP error response from the GitHub API.
 // It carries the status code so callers can distinguish between
 // different failure modes (e.g. 404 vs 500).
 //
-// The Body field stores up to 64 KiB of the raw response for programmatic
+// The Body field stores up to 4 KiB of the raw response for programmatic
 // inspection. Error() truncates to 200 bytes for safe logging, but callers
 // should avoid logging or propagating Body directly in production since it may
 // contain sensitive details from the upstream server.
@@ -90,109 +80,85 @@ func asAPIError(err error) (*APIError, bool) {
 	return nil, false
 }
 
+// clientConfig holds optional configuration for NewClient.
+type clientConfig struct {
+	allowInsecureHTTP bool
+}
+
+// ClientOption configures optional behavior of NewClient.
+type ClientOption func(*clientConfig)
+
+// AllowInsecureHTTP permits the client to use HTTP (non-TLS) base URLs.
+// This should only be used for trusted internal deployments or testing.
+func AllowInsecureHTTP() ClientOption {
+	return func(c *clientConfig) {
+		c.allowInsecureHTTP = true
+	}
+}
+
 // Client interacts with the GitHub API.
 // A Client is safe for concurrent use by multiple goroutines.
 // SetHTTPClient and SetRetryBackoff are intended for test setup only and must
 // be called before any goroutines issue requests; they have no synchronization.
 type Client struct {
-	baseURL    string
-	token      string
-	httpClient *http.Client
-
-	// allowInsecureHTTP permits requests to HTTP (non-TLS) endpoints.
-	// When false, doRequest rejects URLs with an http:// scheme.
+	baseURL           string
+	token             string
 	allowInsecureHTTP bool
+	httpClient        *http.Client
 
 	// retryBackoff defines the delays between retry attempts for 429 responses.
 	// retryBackoff[i] is the delay before attempt i+1 (after attempt i fails).
-	// If nil, defaults to {1s, 2s}.
+	// If nil, defaults to {1s, 2s}. Set to shorter durations in tests via SetRetryBackoff.
 	retryBackoff []time.Duration
-
-	// now returns the current time. Defaults to time.Now.
-	// Override in tests to control HTTP-date Retry-After calculations.
-	now func() time.Time
 }
 
-// defaultCheckRedirect is the redirect policy used by NewClient.
-// NOTE: This function is intentionally duplicated in gitea/client.go (and vice versa)
-// because the packages are separate. Changes here must be mirrored there.
-// It rejects HTTPS->HTTP protocol downgrades (to prevent plaintext leakage)
-// and cross-host redirects (to prevent following responses from untrusted
-// endpoints). Same-host, same-or-upgraded-scheme redirects are allowed.
+// defaultCheckRedirect is the redirect policy used by NewClient and SetHTTPClient(nil).
+// It rejects HTTPS→HTTP protocol downgrades (to prevent plaintext leakage) and strips
+// the Authorization header on cross-host redirects to prevent credential leakage to
+// third-party hosts (e.g. CDN redirects from GitHub).
 func defaultCheckRedirect(req *http.Request, via []*http.Request) error {
 	if len(via) >= 10 {
 		return fmt.Errorf("stopped after 10 redirects")
 	}
-	// Guard for direct invocation in tests and any future callers;
-	// net/http guarantees len(via) >= 1 during actual redirects.
+	// Guard: net/http guarantees len(via) >= 1 but this is undocumented;
+	// defend against zero-length to avoid panic on index out of range.
 	if len(via) == 0 {
 		return nil
 	}
 	prev := via[len(via)-1]
-	// Reject protocol downgrade: HTTPS->HTTP leaks request metadata over plaintext.
+	// Reject protocol downgrade: HTTPS→HTTP leaks request metadata over plaintext.
 	if prev.URL.Scheme == "https" && req.URL.Scheme == "http" {
-		return fmt.Errorf("refusing redirect: HTTPS to HTTP downgrade (%s -> %s)", prev.URL.Host, req.URL.Host)
+		return fmt.Errorf("refusing redirect from HTTPS to HTTP (%s → %s)", prev.URL.Host, req.URL.Host)
 	}
-	// Reject cross-host redirect entirely to avoid consuming responses
-	// from untrusted endpoints.
+	// Strip Authorization on cross-host redirect to avoid leaking credentials
+	// to third-party hosts (GitHub legitimately redirects to CDN hosts).
 	if req.URL.Host != prev.URL.Host {
-		return fmt.Errorf("refusing redirect: cross-host (%s -> %s)", prev.URL.Host, req.URL.Host)
+		req.Header.Del("Authorization")
 	}
 	return nil
 }
 
-// ClientOption configures optional behavior of a Client.
-type ClientOption func(*clientConfig)
-
-type clientConfig struct {
-	allowInsecureHTTP    bool
-	insecureIsTestBypass bool
-}
-
-// AllowInsecureHTTP permits sending credentials over plaintext HTTP connections.
-// In production, this option is gated by the REVIEW_BOT_ALLOW_INSECURE=1
-// environment variable. Without the env var set, the option is ignored
-// and a warning is logged.
-//
-// For tests, use AllowInsecureHTTPForTest (defined in a _test.go file in the same package) which bypasses the env gate.
-func AllowInsecureHTTP() ClientOption {
-	return func(cfg *clientConfig) {
-		cfg.allowInsecureHTTP = true
-	}
-}
-
 // NewClient creates a new GitHub API client.
 // If baseURL is empty, it defaults to https://api.github.com.
 // For GitHub Enterprise, pass the API base URL (e.g. https://github.concur.com/api/v3).
+// The baseURL must use HTTPS; pass AllowInsecureHTTP() as an option to permit HTTP
+// for trusted internal deployments (e.g. local testing).
 func NewClient(token, baseURL string, opts ...ClientOption) *Client {
 	if baseURL == "" {
 		baseURL = defaultBaseURL
 	}
-
-	var cfg clientConfig
-	for _, opt := range opts {
-		opt(&cfg)
+	cfg := clientConfig{}
+	for _, o := range opts {
+		o(&cfg)
 	}
-
-	if cfg.allowInsecureHTTP && !cfg.insecureIsTestBypass {
-		if os.Getenv("REVIEW_BOT_ALLOW_INSECURE") != "1" {
-			slog.Warn("AllowInsecureHTTP ignored: set REVIEW_BOT_ALLOW_INSECURE=1 to enable")
-			cfg.allowInsecureHTTP = false
-		} else {
-			slog.Warn("AllowInsecureHTTP enabled — credentials may be sent over plaintext",
-				"env", "REVIEW_BOT_ALLOW_INSECURE=1")
-		}
-	}
-
 	return &Client{
 		baseURL:           strings.TrimRight(baseURL, "/"),
-		token:             token,
 		allowInsecureHTTP: cfg.allowInsecureHTTP,
+		token:             token,
 		httpClient: &http.Client{
 			Timeout:       30 * time.Second,
 			CheckRedirect: defaultCheckRedirect,
 		},
-		now: time.Now,
 	}
 }
 
@@ -200,7 +166,7 @@ func NewClient(token, baseURL string, opts ...ClientOption) *Client {
 // This is intended for test setup only to inject mock transports; it must be
 // called before any goroutines issue requests.
 //
-// Passing nil restores the default client (30s timeout + redirect-rejecting
+// Passing nil restores the default client (30s timeout + auth-stripping
 // CheckRedirect policy matching NewClient).
 //
 // Callers providing a non-nil client are responsible for configuring a safe
@@ -216,88 +182,68 @@ func (c *Client) SetHTTPClient(hc *http.Client) {
 	c.httpClient = hc
 }
 
-// SetRetryBackoff sets the delays between retry attempts.
-// This is intended for testing to speed up retry tests.
-//
-// Note: if an empty non-nil slice is provided, Retry-After delays parsed from
-// server responses will be computed and capped but not applied (because
-// attempt < len(backoff) is always false). This is acceptable for the
-// test-only use case but callers should be aware of this edge case.
-func (c *Client) SetRetryBackoff(backoff []time.Duration) {
-	c.retryBackoff = backoff
+// SetRetryBackoff configures the retry backoff durations for testing.
+// It must be called before any goroutines issue requests.
+// The slice must have exactly maxRetryAttempts-1 entries (one delay per retry gap).
+// In production the default {1s, 2s} applies.
+func (c *Client) SetRetryBackoff(d []time.Duration) error {
+	if len(d) != maxRetryAttempts-1 {
+		return fmt.Errorf("github: backoff length %d does not match maxRetryAttempts-1 (%d)", len(d), maxRetryAttempts-1)
+	}
+	c.retryBackoff = d
+	return nil
 }
 
-// parseRetryAfter parses a Retry-After header value, supporting both integer
-// seconds (e.g. "120") and HTTP-date format (e.g. "Thu, 01 Dec 2025 16:00:00 GMT")
-// as specified in RFC 7231 §7.1.3.
-//
-// For integer values, it returns the duration directly.
-// For HTTP-date values, it computes the delay as the difference between the
-// parsed time and now. If the date is in the past, it returns 0.
-//
-// Returns (0, false) if the value cannot be parsed as either format.
-func (c *Client) parseRetryAfter(value string) (time.Duration, bool) {
-	value = strings.TrimSpace(value)
+// requestOptions holds per-request configuration for doRequestCore.
+type requestOptions struct {
+	// bodyFn returns a fresh io.Reader for the request body on each attempt.
+	// Must be non-nil for any request that carries a body (POST, PUT, PATCH,
+	// or DELETE when a body is required by the API).
+	// Returning a fresh reader on each call allows retries to re-send the body.
+	bodyFn func() io.Reader
 
-	// Try integer seconds first (most common from GitHub).
-	// RFC 7231 allows delta-seconds of 0 to indicate immediate retry.
-	if seconds, err := strconv.Atoi(value); err == nil && seconds >= 0 {
-		return time.Duration(seconds) * time.Second, true
-	}
+	// accept overrides the default Accept header. Empty means "application/vnd.github+json".
+	accept string
 
-	// Try HTTP-date format (RFC 7231 §7.1.3).
-	// http.ParseTime handles RFC 1123, RFC 850, and ASCTIME formats.
-	if retryAt, err := http.ParseTime(value); err == nil {
-		delay := retryAt.Sub(c.now())
-		if delay < 0 {
-			delay = 0
-		}
-		return delay, true
-	}
-
-	return 0, false
+	// extraHeaders are additional headers to set on each request attempt.
+	extraHeaders map[string]string
 }
 
-// redactURL redacts sensitive components from a URL for safe inclusion in error
-// messages and log output. It removes userinfo (e.g., user:pass@) and replaces
-// query parameters with a placeholder.
-func redactURL(rawURL string) string {
-	u, err := url.Parse(rawURL)
-	if err != nil {
-		return "<unparseable URL>"
-	}
-	u.User = nil
+// doRequestCore is the shared implementation for all HTTP requests with retry
+// on 429 rate limit responses. It respects the Retry-After header when present
+// (capped at maxRetryAfter). Transport errors are not retried.
+func (c *Client) doRequestCore(ctx context.Context, method, reqURL string, opts requestOptions) ([]byte, error) {
+	const maxRetryAfter = 120 * time.Second
 
-	if u.RawQuery != "" {
-		u.RawQuery = "<redacted>"
-	}
-	return u.String()
-}
+	// maxErrorBodyBytes limits how much of an error response body is stored.
+	// Kept small (4 KiB) to reduce the risk of sensitive data leakage if callers
+	// log APIError.Body directly. Error() further truncates to 200 bytes.
+	const maxErrorBodyBytes = 4 * 1024
 
-// doRequest performs an HTTP request with retry on 429 rate limit responses.
-// It respects the Retry-After header when present, supporting both integer
-// seconds and HTTP-date formats (capped at maxRetryAfter).
-func (c *Client) doRequest(ctx context.Context, method, reqURL string, accept string) ([]byte, error) {
-	// NOTE: This parses reqURL a second time (http.NewRequestWithContext parses it
-	// again internally). Acceptable cost: URL parsing is cheap and threading the
-	// parsed *url.URL through would complicate the interface for negligible gain.
-	if !c.allowInsecureHTTP {
+	// backoff holds per-attempt delays: backoff[i] is the delay before attempt i+1.
+	// Length must be maxRetryAttempts-1 (one entry per retry gap).
+	// SetRetryBackoff validates at configuration time; the default is always valid.
+	defaultBackoff := []time.Duration{1 * time.Second, 2 * time.Second}
+	var backoff []time.Duration
+	if c.retryBackoff != nil && len(c.retryBackoff) == maxRetryAttempts-1 {
+		backoff = make([]time.Duration, len(c.retryBackoff))
+		copy(backoff, c.retryBackoff)
+	} else {
+		backoff = make([]time.Duration, len(defaultBackoff))
+		copy(backoff, defaultBackoff)
+	}
+
+	// Reject non-HTTPS URLs early since the URL is immutable across retries.
+	if c.token != "" && !c.allowInsecureHTTP {
 		parsed, err := url.Parse(reqURL)
 		if err != nil {
 			return nil, fmt.Errorf("parse request URL: %w", err)
 		}
-		if strings.EqualFold(parsed.Scheme, "http") {
-			return nil, fmt.Errorf("refusing HTTP request to %s: use HTTPS or set AllowInsecureHTTP option", redactURL(reqURL))
+		if !strings.EqualFold(parsed.Scheme, "https") {
+			return nil, fmt.Errorf("refusing to send credentials over non-HTTPS URL %q (use AllowInsecureHTTP option for trusted networks)", reqURL)
 		}
 	}
 
-	var backoff []time.Duration
-	if c.retryBackoff != nil {
-		backoff = append([]time.Duration(nil), c.retryBackoff...)
-	} else {
-		backoff = []time.Duration{1 * time.Second, 2 * time.Second}
-	}
-
 	var lastErr error
 	for attempt := 0; attempt < maxRetryAttempts; attempt++ {
 		if attempt > 0 {
@@ -317,42 +263,63 @@ func (c *Client) doRequest(ctx context.Context, method, reqURL string, accept st
 			}
 		}
 
-		req, err := http.NewRequestWithContext(ctx, method, reqURL, nil)
+		var body io.Reader
+		if opts.bodyFn != nil {
+			body = opts.bodyFn()
+		}
+		req, err := http.NewRequestWithContext(ctx, method, reqURL, body)
 		if err != nil {
 			return nil, fmt.Errorf("create request: %w", err)
 		}
-		req.Header.Set("Authorization", "Bearer "+c.token)
-		if accept != "" {
-			req.Header.Set("Accept", accept)
+		if c.token != "" {
+			// Bearer is the OAuth2 standard and is accepted by GitHub for both
+			// classic PATs and fine-grained tokens. The alternative "token" scheme
+			// is GitHub-specific and offers no additional compatibility.
+			req.Header.Set("Authorization", "Bearer "+c.token)
+		}
+		req.Header.Set("User-Agent", userAgent)
+		if opts.accept != "" {
+			req.Header.Set("Accept", opts.accept)
 		} else {
 			req.Header.Set("Accept", "application/vnd.github+json")
 		}
+		for k, v := range opts.extraHeaders {
+			req.Header.Set(k, v)
+		}
 
 		resp, err := c.httpClient.Do(req)
 		if err != nil {
 			return nil, fmt.Errorf("do request: %w", err)
 		}
 
-		if resp.StatusCode >= 200 && resp.StatusCode < 300 {
-			body, err := io.ReadAll(io.LimitReader(resp.Body, maxResponseBodyBytes))
-			resp.Body.Close()
-			if err != nil {
-				return nil, fmt.Errorf("read response body: %w", err)
-			}
-			return body, nil
+		// Capture response metadata before handleResponse takes body ownership.
+		respStatus := resp.StatusCode
+		retryAfterHeader := resp.Header.Get("Retry-After")
+
+		respBody, done, handleErr := c.handleResponse(resp, maxResponseBytes, maxErrorBodyBytes)
+		if done {
+			return respBody, handleErr
 		}
-
-		errBody, _ := io.ReadAll(io.LimitReader(resp.Body, maxErrorBodyBytes))
-		resp.Body.Close()
-
-		lastErr = &APIError{StatusCode: resp.StatusCode, Body: string(errBody)}
+		lastErr = handleErr
 
 		// Retry on 429 rate limit
-		if resp.StatusCode == http.StatusTooManyRequests && attempt < maxRetryAttempts-1 {
+		if respStatus == http.StatusTooManyRequests && attempt < maxRetryAttempts-1 {
 			// Check for Retry-After header and override backoff if present.
 			// Supports both integer seconds (common) and HTTP-date format (RFC 7231).
-			if ra := resp.Header.Get("Retry-After"); ra != "" {
-				if delay, ok := c.parseRetryAfter(ra); ok {
+			if ra := retryAfterHeader; ra != "" {
+				if seconds, err := strconv.Atoi(ra); err == nil && seconds > 0 {
+					delay := time.Duration(seconds) * time.Second
+					if delay > maxRetryAfter {
+						delay = maxRetryAfter
+					}
+					if attempt < len(backoff) {
+						backoff[attempt] = delay
+					}
+				} else if retryAt, err := http.ParseTime(ra); err == nil {
+					delay := time.Until(retryAt)
+					if delay < 0 {
+						delay = 0
+					}
 					if delay > maxRetryAfter {
 						delay = maxRetryAfter
 					}
@@ -371,461 +338,62 @@ func (c *Client) doRequest(ctx context.Context, method, reqURL string, accept st
 	return nil, lastErr
 }
 
-// doGet is a convenience wrapper for GET requests with the default Accept header.
-func (c *Client) doGet(ctx context.Context, url string) ([]byte, error) {
-	return c.doRequest(ctx, http.MethodGet, url, "")
+// doRequest performs an HTTP request with retry on 429 rate limit responses.
+// It respects the Retry-After header when present (capped at maxRetryAfter).
+// Transport errors (network failures, context cancellation) are not retried.
+func (c *Client) doRequest(ctx context.Context, method, reqURL string, accept string) ([]byte, error) {
+	return c.doRequestCore(ctx, method, reqURL, requestOptions{accept: accept})
 }
 
-// doRequestWithBody performs an HTTP request with an optional body, applying the
-// same HTTPS enforcement as doRequest. It is used by write methods (POST, PUT,
-// DELETE) that bypass the retry loop in doRequest because write operations are
-// not idempotent.
-//
-// body may be nil for requests that carry no payload (e.g. DELETE).
-// When body is non-nil, Content-Type is set to application/json.
-func (c *Client) doRequestWithBody(ctx context.Context, method, reqURL string, body []byte) ([]byte, error) {
-	if !c.allowInsecureHTTP {
-		parsed, err := url.Parse(reqURL)
-		if err != nil {
-			return nil, fmt.Errorf("parse request URL: %w", err)
-		}
-		if strings.EqualFold(parsed.Scheme, "http") {
-			return nil, fmt.Errorf("refusing HTTP request to %s: use HTTPS or set AllowInsecureHTTP option", redactURL(reqURL))
-		}
-	}
-
-	var reqBody io.Reader
-	if body != nil {
-		reqBody = bytes.NewReader(body)
-	}
-
-	req, err := http.NewRequestWithContext(ctx, method, reqURL, reqBody)
-	if err != nil {
-		return nil, fmt.Errorf("create request: %w", err)
-	}
-	req.Header.Set("Authorization", "Bearer "+c.token)
-	req.Header.Set("Accept", "application/vnd.github+json")
-	if body != nil {
-		req.Header.Set("Content-Type", "application/json")
-	}
-
-	resp, err := c.httpClient.Do(req)
-	if err != nil {
-		return nil, fmt.Errorf("do request: %w", err)
-	}
+// handleResponse reads and closes the response body, returning the result.
+// It uses defer to ensure the body is always closed regardless of code path.
+// Returns (body, done, err) where done=true means the caller should return immediately.
+func (c *Client) handleResponse(resp *http.Response, maxRespBytes int, maxErrBytes int) ([]byte, bool, error) {
 	defer resp.Body.Close()
 
 	if resp.StatusCode >= 200 && resp.StatusCode < 300 {
-		respBody, err := io.ReadAll(io.LimitReader(resp.Body, maxResponseBodyBytes))
+		body, err := io.ReadAll(io.LimitReader(resp.Body, int64(maxRespBytes)+1))
 		if err != nil {
-			return nil, fmt.Errorf("read response body: %w", err)
+			return nil, true, fmt.Errorf("read response body: %w", err)
 		}
-		return respBody, nil
+		if len(body) > maxRespBytes {
+			return nil, true, fmt.Errorf("response body exceeded %d bytes", maxRespBytes)
+		}
+		return body, true, nil
 	}
 
-	errBody, _ := io.ReadAll(io.LimitReader(resp.Body, maxErrorBodyBytes))
-	return nil, &APIError{StatusCode: resp.StatusCode, Body: string(errBody)}
+	errBody, readErr := io.ReadAll(io.LimitReader(resp.Body, int64(maxErrBytes)))
+	if readErr != nil && len(errBody) == 0 {
+		errBody = []byte(fmt.Sprintf("[error reading response body: %v]", readErr))
+	}
+	return nil, false, &APIError{StatusCode: resp.StatusCode, Body: string(errBody)}
 }
 
-// --- API types ---
-
-// PullRequest holds relevant PR metadata.
-type PullRequest struct {
-	Title string `json:"title"`
-	Body  string `json:"body"`
-	Head  struct {
-		Sha string `json:"sha"`
-		Ref string `json:"ref"`
-	} `json:"head"`
-	Draft bool `json:"draft"`
+// doGet is a convenience wrapper for GET requests with the default Accept header.
+func (c *Client) doGet(ctx context.Context, reqURL string) ([]byte, error) {
+	return c.doRequest(ctx, http.MethodGet, reqURL, "")
 }
 
-// CommitStatus represents a single CI status entry.
-// GitHub returns "state" not "status"; this type uses Status for consistency
-// with the gitea package (both are normalized before use).
-type CommitStatus struct {
-	Status      string `json:"state"` // GitHub field is "state"
-	Context     string `json:"context"`
-	Description string `json:"description"`
-	TargetURL   string `json:"target_url"`
+// doRequestWithBody is like doRequest but sends a request body.
+// It accepts the raw body bytes and sets Content-Type to application/json.
+// Retry semantics match doRequest (retries on 429 with Retry-After support).
+func (c *Client) doRequestWithBody(ctx context.Context, method, reqURL string, reqBody []byte) ([]byte, error) {
+	var opts requestOptions
+	if reqBody != nil {
+		opts.bodyFn = func() io.Reader { return bytes.NewReader(reqBody) }
+		opts.extraHeaders = map[string]string{"Content-Type": "application/json"}
+	}
+	return c.doRequestCore(ctx, method, reqURL, opts)
 }
 
-// ChangedFile represents a file modified in a PR.
-type ChangedFile struct {
-	Filename string `json:"filename"`
-	Status   string `json:"status"`
-}
-
-// ReviewComment represents an inline comment to attach to a review.
-// GitHub uses "position" (diff hunk position), whereas Gitea uses "new_position" (line number).
-// When posting inline comments on GitHub, position is required; line numbers
-// from the diff cannot be used directly.
-type ReviewComment struct {
-	ID       int64  `json:"id,omitempty"`
-	Path     string `json:"path"`
-	Position int64  `json:"position,omitempty"`   // GitHub diff hunk position
-	Line     int64  `json:"line,omitempty"`        // GitHub absolute line number (alternative to position)
-	Side     string `json:"side,omitempty"`        // "RIGHT" or "LEFT"
-	Body     string `json:"body"`
-}
-
-// Review represents a pull request review from the GitHub API.
-type Review struct {
-	ID   int64  `json:"id"`
-	Body string `json:"body"`
-	User struct {
-		Login string `json:"login"`
-	} `json:"user"`
-	State string `json:"state"`
-}
-
-// contentResponse is the GitHub contents API response for a single file.
-type contentResponse struct {
-	Name     string `json:"name"`
-	Path     string `json:"path"`
-	Type     string `json:"type"`     // "file" or "dir" or "symlink" or "submodule"
-	Content  string `json:"content"`  // Base64-encoded file content (with embedded newlines)
-	Encoding string `json:"encoding"` // "base64" or ""
-}
-
-// ContentEntry represents a file or directory entry from the contents API.
-type ContentEntry struct {
-	Name string `json:"name"`
-	Path string `json:"path"`
-	Type string `json:"type"` // "file" or "dir"
-}
-
-// --- PR methods ---
-
-// GetPullRequest fetches PR metadata.
-func (c *Client) GetPullRequest(ctx context.Context, owner, repo string, number int) (*PullRequest, error) {
-	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d",
-		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
-	body, err := c.doGet(ctx, reqURL)
+// doJSONRequest performs an HTTP request with a JSON body and returns the response body.
+// It delegates retry/backoff/429 handling to doRequestWithBody.
+// This is a general-purpose helper used by any method that needs to send JSON payloads
+// (e.g. PostReview, DismissReview).
+func (c *Client) doJSONRequest(ctx context.Context, method, reqURL string, payload any) ([]byte, error) {
+	jsonBody, err := json.Marshal(payload)
 	if err != nil {
-		return nil, fmt.Errorf("fetch PR: %w", err)
+		return nil, fmt.Errorf("marshal request body: %w", err)
 	}
-	var pr PullRequest
-	if err := json.Unmarshal(body, &pr); err != nil {
-		return nil, fmt.Errorf("parse PR JSON: %w", err)
-	}
-	return &pr, nil
-}
-
-// GetPullRequestDiff fetches the unified diff for a PR.
-func (c *Client) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
-	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d",
-		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
-	body, err := c.doRequest(ctx, http.MethodGet, reqURL, "application/vnd.github.diff")
-	if err != nil {
-		return "", fmt.Errorf("fetch diff: %w", err)
-	}
-	return string(body), nil
-}
-
-// GetPullRequestFiles fetches the list of files changed in a PR.
-// GitHub paginates this endpoint (100 per page max).
-func (c *Client) GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]ChangedFile, error) {
-	const perPage = 100
-	var all []ChangedFile
-	for page := 1; ; page++ {
-		reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/files?per_page=%d&page=%d",
-			c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number, perPage, page)
-		body, err := c.doGet(ctx, reqURL)
-		if err != nil {
-			return nil, fmt.Errorf("fetch PR files (page %d): %w", page, err)
-		}
-		var batch []ChangedFile
-		if err := json.Unmarshal(body, &batch); err != nil {
-			return nil, fmt.Errorf("parse PR files JSON (page %d): %w", page, err)
-		}
-		all = append(all, batch...)
-		if len(batch) < perPage {
-			break
-		}
-	}
-	return all, nil
-}
-
-// GetCommitStatuses fetches CI statuses for a commit SHA.
-// GitHub has two status systems: legacy "commit statuses" and newer "check runs".
-// This method returns commit statuses only; check runs are a separate API.
-// Note: GitHub returns "state" in the JSON; CommitStatus.Status is tagged accordingly.
-func (c *Client) GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]CommitStatus, error) {
-	const perPage = 100
-	var all []CommitStatus
-	for page := 1; ; page++ {
-		reqURL := fmt.Sprintf("%s/repos/%s/%s/commits/%s/statuses?per_page=%d&page=%d",
-			c.baseURL, url.PathEscape(owner), url.PathEscape(repo), url.PathEscape(sha), perPage, page)
-		body, err := c.doGet(ctx, reqURL)
-		if err != nil {
-			return nil, fmt.Errorf("fetch commit statuses (page %d): %w", page, err)
-		}
-		var batch []CommitStatus
-		if err := json.Unmarshal(body, &batch); err != nil {
-			return nil, fmt.Errorf("parse statuses JSON (page %d): %w", page, err)
-		}
-		all = append(all, batch...)
-		if len(batch) < perPage {
-			break
-		}
-	}
-	return all, nil
-}
-
-// --- File content methods ---
-
-// GetFileContent fetches a file from the default branch of a repo.
-// GitHub returns base64-encoded content; this method decodes it.
-func (c *Client) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
-	return c.getFileContentAtRef(ctx, owner, repo, filepath, "")
-}
-
-// GetFileContentRef fetches a file from a specific ref (branch/tag/sha).
-func (c *Client) GetFileContentRef(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
-	return c.getFileContentAtRef(ctx, owner, repo, filepath, ref)
-}
-
-// getFileContentAtRef fetches a file at the given ref (empty = default branch).
-// GitHub's contents API returns base64-encoded file content.
-func (c *Client) getFileContentAtRef(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
-	reqURL := fmt.Sprintf("%s/repos/%s/%s/contents/%s",
-		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), escapePath(filepath))
-	if ref != "" {
-		reqURL += "?ref=" + url.QueryEscape(ref)
-	}
-	body, err := c.doGet(ctx, reqURL)
-	if err != nil {
-		return "", fmt.Errorf("fetch file %s: %w", filepath, err)
-	}
-	var resp contentResponse
-	if err := json.Unmarshal(body, &resp); err != nil {
-		return "", fmt.Errorf("parse file content JSON for %s: %w", filepath, err)
-	}
-	if resp.Type != "file" {
-		return "", fmt.Errorf("path %s is a %s, not a file", filepath, resp.Type)
-	}
-	if resp.Encoding == "base64" {
-		// GitHub embeds newlines in the base64 content for readability.
-		// Strip them before decoding.
-		cleaned := strings.ReplaceAll(resp.Content, "\n", "")
-		decoded, err := base64.StdEncoding.DecodeString(cleaned)
-		if err != nil {
-			return "", fmt.Errorf("decode base64 content for %s: %w", filepath, err)
-		}
-		return string(decoded), nil
-	}
-	// Non-base64 encoding (shouldn't happen normally, but handle gracefully).
-	return resp.Content, nil
-}
-
-// ListContents lists files and directories at a given path.
-// Pass an empty path to list the repository root.
-// GitHub returns a single object (not array) when path is a file — this
-// method normalizes both cases to a slice, matching Gitea's behavior.
-func (c *Client) ListContents(ctx context.Context, owner, repo, path string) ([]ContentEntry, error) {
-	var reqURL string
-	if path == "" || path == "." {
-		reqURL = fmt.Sprintf("%s/repos/%s/%s/contents",
-			c.baseURL, url.PathEscape(owner), url.PathEscape(repo))
-	} else {
-		reqURL = fmt.Sprintf("%s/repos/%s/%s/contents/%s",
-			c.baseURL, url.PathEscape(owner), url.PathEscape(repo), escapePath(path))
-	}
-	body, err := c.doGet(ctx, reqURL)
-	if err != nil {
-		return nil, fmt.Errorf("list contents %s: %w", path, err)
-	}
-
-	var entries []ContentEntry
-	if err := json.Unmarshal(body, &entries); err != nil {
-		// GitHub returns a single object when path is a file (not an array).
-		var single contentResponse
-		if err2 := json.Unmarshal(body, &single); err2 != nil {
-			return nil, fmt.Errorf("parse contents JSON: %w", err)
-		}
-		if single.Name == "" && single.Path == "" {
-			return nil, fmt.Errorf("parse contents JSON: empty response for path %q", path)
-		}
-		entries = []ContentEntry{{
-			Name: single.Name,
-			Path: single.Path,
-			Type: single.Type,
-		}}
-	}
-	return entries, nil
-}
-
-// GetAllFilesInPath recursively fetches all file contents under a path.
-// If the path is a file, returns just that file's content.
-// If the path is a directory, recursively fetches all files within it.
-func (c *Client) GetAllFilesInPath(ctx context.Context, owner, repo, path string) (map[string]string, error) {
-	results := make(map[string]string)
-
-	entries, err := c.ListContents(ctx, owner, repo, path)
-	if err != nil {
-		if !IsNotFound(err) {
-			return nil, fmt.Errorf("list contents %q: %w", path, err)
-		}
-		// 404 means path may be a file — try fetching directly.
-		content, fileErr := c.GetFileContent(ctx, owner, repo, path)
-		if fileErr != nil {
-			return nil, fmt.Errorf("path %q is neither a file nor directory: %w", path, fileErr)
-		}
-		results[path] = content
-		return results, nil
-	}
-
-	for _, entry := range entries {
-		switch entry.Type {
-		case "file":
-			content, err := c.GetFileContent(ctx, owner, repo, entry.Path)
-			if err != nil {
-				slog.Warn("could not fetch file from patterns repo", "file", entry.Path, "error", err)
-				continue
-			}
-			results[entry.Path] = content
-		case "dir":
-			subResults, err := c.GetAllFilesInPath(ctx, owner, repo, entry.Path)
-			if err != nil {
-				slog.Warn("could not recurse into directory", "dir", entry.Path, "error", err)
-				continue
-			}
-			for k, v := range subResults {
-				results[k] = v
-			}
-		}
-	}
-	return results, nil
-}
-
-// --- Review methods ---
-
-// PostReview submits a review to a PR.
-// event should be one of "APPROVE", "REQUEST_CHANGES", or "COMMENT".
-// commitID anchors the review to a specific commit SHA. If empty, defaults to current HEAD.
-// comments are optional inline comments; GitHub uses diff hunk position (not line numbers).
-// Note: unlike Gitea, GitHub does not support deleting submitted reviews.
-// Use COMMENT event to supersede old reviews.
-func (c *Client) PostReview(ctx context.Context, owner, repo string, number int, event, body, commitID string, comments []ReviewComment) (*Review, error) {
-	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/reviews",
-		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
-
-	payload := struct {
-		Body     string          `json:"body"`
-		Event    string          `json:"event"`
-		CommitID string          `json:"commit_id,omitempty"`
-		Comments []ReviewComment `json:"comments,omitempty"`
-	}{
-		Body:     body,
-		Event:    event,
-		CommitID: commitID,
-		Comments: comments,
-	}
-
-	data, err := json.Marshal(payload)
-	if err != nil {
-		return nil, fmt.Errorf("marshal review payload: %w", err)
-	}
-
-	respBody, err := c.doRequestWithBody(ctx, http.MethodPost, reqURL, data)
-	if err != nil {
-		return nil, fmt.Errorf("post review: %w", err)
-	}
-
-	var review Review
-	if err := json.Unmarshal(respBody, &review); err != nil {
-		return nil, fmt.Errorf("parse review response: %w", err)
-	}
-	return &review, nil
-}
-
-// ListReviews returns all reviews on a pull request.
-// GitHub paginates via Link header; this method uses per_page=100.
-func (c *Client) ListReviews(ctx context.Context, owner, repo string, number int) ([]Review, error) {
-	const perPage = 100
-	var all []Review
-	for page := 1; ; page++ {
-		reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/reviews?per_page=%d&page=%d",
-			c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number, perPage, page)
-		body, err := c.doGet(ctx, reqURL)
-		if err != nil {
-			return nil, fmt.Errorf("list reviews (page %d): %w", page, err)
-		}
-		var batch []Review
-		if err := json.Unmarshal(body, &batch); err != nil {
-			return nil, fmt.Errorf("parse reviews (page %d): %w", page, err)
-		}
-		all = append(all, batch...)
-		if len(batch) < perPage {
-			break
-		}
-	}
-	return all, nil
-}
-
-// DeleteReview attempts to delete a pull request review.
-// GitHub only allows deleting PENDING (draft) reviews. Submitted reviews cannot
-// be deleted via the API; this method returns a descriptive error in that case.
-// review-bot callers should handle this error gracefully (e.g., by not attempting
-// supersede and instead posting a new review alongside the old one).
-func (c *Client) DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error {
-	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/reviews/%d",
-		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number, reviewID)
-
-	// nil body: the GitHub DELETE endpoint for reviews requires no request body.
-	_, err := c.doRequestWithBody(ctx, http.MethodDelete, reqURL, nil)
-	if err != nil {
-		return fmt.Errorf("delete review: %w", err)
-	}
-	return nil
-}
-
-// GetAuthenticatedUser returns the login of the authenticated user.
-func (c *Client) GetAuthenticatedUser(ctx context.Context) (string, error) {
-	reqURL := c.baseURL + "/user"
-	body, err := c.doGet(ctx, reqURL)
-	if err != nil {
-		return "", fmt.Errorf("get authenticated user: %w", err)
-	}
-	var result struct {
-		Login string `json:"login"`
-	}
-	if err := json.Unmarshal(body, &result); err != nil {
-		return "", fmt.Errorf("parse user response: %w", err)
-	}
-	return result.Login, nil
-}
-
-// RequestReviewer adds a user as a requested reviewer on a pull request.
-// This is idempotent — requesting an already-requested reviewer is a no-op.
-func (c *Client) RequestReviewer(ctx context.Context, owner, repo string, number int, reviewer string) error {
-	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/requested_reviewers",
-		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
-
-	payload := struct {
-		Reviewers []string `json:"reviewers"`
-	}{Reviewers: []string{reviewer}}
-	data, err := json.Marshal(payload)
-	if err != nil {
-		return fmt.Errorf("marshal reviewer request: %w", err)
-	}
-
-	_, err = c.doRequestWithBody(ctx, http.MethodPost, reqURL, data)
-	if err != nil {
-		return fmt.Errorf("request reviewer: %w", err)
-	}
-	return nil
-}
-
-// --- helpers ---
-
-// escapePath escapes each segment of a relative file path for use in URLs.
-// Slashes are preserved as path separators; other special characters are escaped.
-func escapePath(p string) string {
-	parts := strings.Split(p, "/")
-	for i, part := range parts {
-		parts[i] = url.PathEscape(part)
-	}
-	return strings.Join(parts, "/")
+	return c.doRequestWithBody(ctx, method, reqURL, jsonBody)
 }

github/conformance_test.go

@@ -0,0 +1,14 @@
+package github_test
+
+import (
+	"gitea.weiker.me/rodin/review-bot/github"
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// Compile-time interface conformance assertion.
+// This verifies github.Client satisfies the full vcs.Client interface
+// (PRReader, FileReader, Reviewer, Identity).
+var _ vcs.Client = (*github.Client)(nil)
+
+// Verify github.Client implements ReviewSuperseder.
+var _ vcs.ReviewSuperseder = (*github.Client)(nil)

github/export_test.go

@@ -1,13 +0,0 @@
-package github
-
-// AllowInsecureHTTPForTest permits sending credentials over plaintext HTTP
-// without requiring the REVIEW_BOT_ALLOW_INSECURE environment variable.
-// This is intended exclusively for test code using httptest.Server.
-//
-// Defined in a _test.go file so it is only available to test binaries.
-func AllowInsecureHTTPForTest() ClientOption {
-	return func(cfg *clientConfig) {
-		cfg.allowInsecureHTTP = true
-		cfg.insecureIsTestBypass = true
-	}
-}

github/files.go

@@ -0,0 +1,160 @@
+package github
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"net/url"
+	"path"
+	"strings"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// GetFileContent fetches a file from a repo at the given ref.
+// Delegates to GetFileContentAtRef with the provided ref.
+func (c *Client) GetFileContent(ctx context.Context, owner, repo, filePath, ref string) (string, error) {
+	return c.GetFileContentAtRef(ctx, owner, repo, filePath, ref)
+}
+
+// GetFileContentAtRef fetches a file at a specific ref from a repo.
+// If ref is empty, the query parameter is omitted (uses default branch).
+//
+// Returns an error if the path contains dot-segments (".", "..") or
+// attempts to traverse above the repository root.
+func (c *Client) GetFileContentAtRef(ctx context.Context, owner, repo, filePath, ref string) (string, error) {
+	escaped, err := escapePath(filePath)
+	if err != nil {
+		return "", fmt.Errorf("invalid file path: %w", err)
+	}
+	reqURL := fmt.Sprintf("%s/repos/%s/%s/contents/%s",
+		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), escaped)
+	if ref != "" {
+		reqURL += "?ref=" + url.QueryEscape(ref)
+	}
+	body, err := c.doGet(ctx, reqURL)
+	if err != nil {
+		return "", fmt.Errorf("fetch file %s: %w", filePath, err)
+	}
+	var resp struct {
+		Content  string `json:"content"`
+		Encoding string `json:"encoding"`
+	}
+	if err := json.Unmarshal(body, &resp); err != nil {
+		return "", fmt.Errorf("parse file content JSON: %w", err)
+	}
+	if resp.Encoding != "base64" {
+		return "", fmt.Errorf("unexpected encoding %q for file %s", resp.Encoding, filePath)
+	}
+	decoded, err := decodeBase64Content(resp.Content)
+	if err != nil {
+		return "", fmt.Errorf("decode base64 content for %s: %w", filePath, err)
+	}
+	return decoded, nil
+}
+
+// ListContents lists files and directories at a given path in a repo.
+// Returns the directory listing from the GitHub contents API.
+// If the path points to a single file (not a directory), the API returns
+// a JSON object instead of an array; this is handled by returning a
+// single-element slice.
+func (c *Client) ListContents(ctx context.Context, owner, repo, filePath string) ([]vcs.ContentEntry, error) {
+	escaped, err := escapePath(filePath)
+	if err != nil {
+		return nil, fmt.Errorf("invalid file path: %w", err)
+	}
+	reqURL := fmt.Sprintf("%s/repos/%s/%s/contents/%s",
+		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), escaped)
+	body, err := c.doGet(ctx, reqURL)
+	if err != nil {
+		return nil, fmt.Errorf("list contents %s: %w", filePath, err)
+	}
+
+	type entry struct {
+		Name string `json:"name"`
+		Path string `json:"path"`
+		Type string `json:"type"`
+	}
+
+	// The GitHub contents API returns an array for directories and an object
+	// for single files. Try array first (common case), then fall back to object.
+	// An empty array ([]) is valid — it represents an empty directory — and
+	// results in a zero-length slice returned without error.
+	var entries []entry
+	if err := json.Unmarshal(body, &entries); err != nil {
+		var single entry
+		if err2 := json.Unmarshal(body, &single); err2 != nil {
+			return nil, fmt.Errorf("parse contents JSON: as array: %v; as object: %w", err, err2)
+		}
+		// Guard against empty objects ({}) or unexpected shapes that
+		// unmarshal successfully but carry no useful data.
+		if single.Name == "" && single.Path == "" && single.Type == "" {
+			return nil, fmt.Errorf("parse contents JSON: unexpected response format")
+		}
+		entries = []entry{single}
+	}
+
+	result := make([]vcs.ContentEntry, len(entries))
+	for i, e := range entries {
+		result[i] = vcs.ContentEntry{
+			Name: e.Name,
+			Path: e.Path,
+			Type: e.Type,
+		}
+	}
+	return result, nil
+}
+
+// escapePath validates and encodes a slash-separated file path for use in
+// GitHub API URLs. Returns an error if the path contains dot-segments ("."
+// or "..") or resolves to a path outside the repository root.
+func escapePath(p string) (string, error) {
+	// Reject paths containing dot-segments rather than silently rewriting them.
+	for _, seg := range strings.Split(p, "/") {
+		if seg == "." || seg == ".." {
+			return "", fmt.Errorf("path contains dot-segment %q: %s", seg, p)
+		}
+	}
+
+	// Use path.Clean for canonical form, then verify it doesn't escape root.
+	cleaned := path.Clean(p)
+	if cleaned == "." || strings.HasPrefix(cleaned, "..") {
+		return "", fmt.Errorf("path resolves outside repository root: %s", p)
+	}
+
+	// Encode each segment individually.
+	parts := strings.Split(cleaned, "/")
+	var encoded []string
+	for _, part := range parts {
+		if part == "" {
+			continue
+		}
+		encoded = append(encoded, url.PathEscape(part))
+	}
+	return strings.Join(encoded, "/"), nil
+}
+
+// maxFileContentSize is the maximum decoded file size (10 MB) to prevent
+// resource exhaustion when decoding base64 content from the API.
+const maxFileContentSize = 10 * 1024 * 1024
+
+// decodeBase64Content decodes base64-encoded content from the GitHub contents API.
+// GitHub returns base64 content with line breaks for formatting; we strip \r and \n before decoding.
+// Returns an error if the decoded content exceeds maxFileContentSize.
+func decodeBase64Content(encoded string) (string, error) {
+	cleaned := strings.NewReplacer("\n", "", "\r", "").Replace(encoded)
+	// Check estimated decoded size before allocating.
+	// Base64 encodes 3 bytes into 4 chars, so decoded ~ len*3/4.
+	if len(cleaned)*3/4 > maxFileContentSize {
+		return "", fmt.Errorf("file content too large: estimated %d bytes exceeds limit of %d", len(cleaned)*3/4, maxFileContentSize)
+	}
+	decoded, err := base64.StdEncoding.DecodeString(cleaned)
+	if err != nil {
+		return "", err
+	}
+	if len(decoded) > maxFileContentSize {
+		return "", fmt.Errorf("file content too large: %d bytes exceeds limit of %d", len(decoded), maxFileContentSize)
+	}
+	return string(decoded), nil
+}

github/files_test.go

@@ -0,0 +1,405 @@
+package github
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestGetFileContent_DelegatesToGetFileContentAtRef(t *testing.T) {
+	var gotRef string
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		gotRef = r.URL.Query().Get("ref")
+		json.NewEncoder(w).Encode(map[string]string{
+			"content":  "dGVzdA==", // "test" in base64
+			"encoding": "base64",
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	// Call with empty ref — should not include ref param
+	content, err := c.GetFileContent(context.Background(), "owner", "repo", "file.go", "")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if content != "test" {
+		t.Errorf("expected 'test', got %q", content)
+	}
+	if gotRef != "" {
+		t.Errorf("expected empty ref, got %q", gotRef)
+	}
+}
+
+func TestGetFileContent_WithRef(t *testing.T) {
+	var gotRef string
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		gotRef = r.URL.Query().Get("ref")
+		json.NewEncoder(w).Encode(map[string]string{
+			"content":  "dGVzdA==",
+			"encoding": "base64",
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetFileContent(context.Background(), "owner", "repo", "file.go", "abc123")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if gotRef != "abc123" {
+		t.Errorf("expected ref 'abc123', got %q", gotRef)
+	}
+}
+
+func TestGetFileContent_404(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetFileContent(context.Background(), "owner", "repo", "missing.go", "")
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+}
+
+func TestGetFileContent_401(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetFileContent(context.Background(), "owner", "repo", "file.go", "")
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+}
+
+func TestGetFileContent_429Retry(t *testing.T) {
+	attempts := 0
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		attempts++
+		if attempts == 1 {
+			w.WriteHeader(429)
+			w.Write([]byte(`{"message":"rate limit"}`))
+			return
+		}
+		json.NewEncoder(w).Encode(map[string]string{
+			"content":  "b2s=",
+			"encoding": "base64",
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+	if err := c.SetRetryBackoff([]time.Duration{1 * time.Millisecond, 1 * time.Millisecond}); err != nil {
+		t.Fatalf("SetRetryBackoff: %v", err)
+	}
+
+	content, err := c.GetFileContent(context.Background(), "owner", "repo", "file.go", "")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if content != "ok" {
+		t.Errorf("expected 'ok', got %q", content)
+	}
+	if attempts != 2 {
+		t.Errorf("expected 2 attempts, got %d", attempts)
+	}
+}
+
+func TestGetFileContent_MalformedJSON(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(200)
+		w.Write([]byte(`not json`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetFileContent(context.Background(), "owner", "repo", "file.go", "")
+	if err == nil {
+		t.Fatal("expected error for malformed JSON")
+	}
+}
+
+func TestListContents_HappyPath(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/repos/owner/repo/contents/src" {
+			t.Errorf("unexpected path: %s", r.URL.Path)
+		}
+		json.NewEncoder(w).Encode([]map[string]string{
+			{"name": "main.go", "path": "src/main.go", "type": "file"},
+			{"name": "lib", "path": "src/lib", "type": "dir"},
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	entries, err := c.ListContents(context.Background(), "owner", "repo", "src")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(entries) != 2 {
+		t.Fatalf("expected 2 entries, got %d", len(entries))
+	}
+	if entries[0].Name != "main.go" {
+		t.Errorf("expected name 'main.go', got %q", entries[0].Name)
+	}
+	if entries[0].Path != "src/main.go" {
+		t.Errorf("expected path 'src/main.go', got %q", entries[0].Path)
+	}
+	if entries[0].Type != "file" {
+		t.Errorf("expected type 'file', got %q", entries[0].Type)
+	}
+	if entries[1].Name != "lib" {
+		t.Errorf("expected name 'lib', got %q", entries[1].Name)
+	}
+	if entries[1].Type != "dir" {
+		t.Errorf("expected type 'dir', got %q", entries[1].Type)
+	}
+}
+
+func TestListContents_404(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.ListContents(context.Background(), "owner", "repo", "missing")
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+}
+
+func TestListContents_401(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.ListContents(context.Background(), "owner", "repo", "src")
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+}
+
+func TestListContents_429Retry(t *testing.T) {
+	attempts := 0
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		attempts++
+		if attempts == 1 {
+			w.WriteHeader(429)
+			w.Write([]byte(`{"message":"rate limit"}`))
+			return
+		}
+		json.NewEncoder(w).Encode([]map[string]string{
+			{"name": "file.go", "path": "file.go", "type": "file"},
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+	if err := c.SetRetryBackoff([]time.Duration{1 * time.Millisecond, 1 * time.Millisecond}); err != nil {
+		t.Fatalf("SetRetryBackoff: %v", err)
+	}
+
+	entries, err := c.ListContents(context.Background(), "owner", "repo", "src")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(entries) != 1 {
+		t.Fatalf("expected 1 entry, got %d", len(entries))
+	}
+	if attempts != 2 {
+		t.Errorf("expected 2 attempts, got %d", attempts)
+	}
+}
+
+func TestListContents_MalformedJSON(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(200)
+		w.Write([]byte(`not json`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.ListContents(context.Background(), "owner", "repo", "src")
+	if err == nil {
+		t.Fatal("expected error for malformed JSON")
+	}
+}
+
+func TestListContents_SingleFile(t *testing.T) {
+	// GitHub Contents API returns a JSON object (not array) for single-file paths
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(200)
+		w.Write([]byte(`{"name":"README.md","path":"README.md","type":"file"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+	entries, err := c.ListContents(context.Background(), "owner", "repo", "README.md")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(entries) != 1 {
+		t.Fatalf("expected 1 entry, got %d", len(entries))
+	}
+	if entries[0].Name != "README.md" {
+		t.Errorf("expected name 'README.md', got %q", entries[0].Name)
+	}
+	if entries[0].Type != "file" {
+		t.Errorf("expected type 'file', got %q", entries[0].Type)
+	}
+}
+
+func TestEscapePath_ValidPaths(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		name string
+		path string
+		want string
+	}{
+		{"simple file", "file.go", "file.go"},
+		{"nested path", "path/to/file.go", "path/to/file.go"},
+		{"special chars", "path/to/my file.go", "path/to/my%20file.go"},
+		{"leading slash stripped", "/path/to/file.go", "path/to/file.go"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			got, err := escapePath(tt.path)
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if got != tt.want {
+				t.Errorf("escapePath(%q) = %q, want %q", tt.path, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestEscapePath_DotSegments(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		name string
+		path string
+	}{
+		{"single dot", "./file.go"},
+		{"double dot", "../file.go"},
+		{"dot in middle", "path/./file.go"},
+		{"parent traversal", "path/../file.go"},
+		{"only dots", ".."},
+		{"nested parent traversal", "a/b/../../c"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			_, err := escapePath(tt.path)
+			if err == nil {
+				t.Fatalf("expected error for path %q, got nil", tt.path)
+			}
+			if !strings.Contains(err.Error(), "dot-segment") {
+				t.Errorf("expected error about dot-segment, got: %v", err)
+			}
+		})
+	}
+}
+
+func TestGetFileContentAtRef_DotSegmentError(t *testing.T) {
+	// Server should never be called — the error is caught before the request.
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		t.Fatal("server should not have been called")
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	_, err := c.GetFileContentAtRef(context.Background(), "owner", "repo", "foo/../bar.go", "main")
+	if err == nil {
+		t.Fatal("expected error for path with dot-segments")
+	}
+	if !strings.Contains(err.Error(), "invalid file path") {
+		t.Errorf("expected 'invalid file path' error, got: %v", err)
+	}
+}
+
+func TestDecodeBase64Content(t *testing.T) {
+	// Test with newlines (GitHub's format)
+	encoded := "cGFja2FnZSBt\nYWlu"
+	decoded, err := decodeBase64Content(encoded)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if decoded != "package main" {
+		t.Errorf("expected 'package main', got %q", decoded)
+	}
+}
+
+func TestDecodeBase64Content_Invalid(t *testing.T) {
+	_, err := decodeBase64Content("not!!!valid!!!base64")
+	if err == nil {
+		t.Fatal("expected error for invalid base64")
+	}
+}
+
+func TestDecodeBase64Content_CRLF(t *testing.T) {
+	// Base64 of "hello world" with CRLF line breaks inserted
+	encoded := "aGVs\r\nbG8g\r\nd29y\r\nbGQ="
+	decoded, err := decodeBase64Content(encoded)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if decoded != "hello world" {
+		t.Errorf("expected 'hello world', got %q", decoded)
+	}
+}
+
+func TestDecodeBase64Content_SizeLimit(t *testing.T) {
+	t.Parallel()
+	// Create base64 content that would decode to > maxFileContentSize.
+	// maxFileContentSize is 10MB. Base64 of 11MB worth of zeros.
+	// We just need something big enough to trigger the estimated size check.
+	// 14MB of base64 chars (decodes to ~10.5MB).
+	huge := strings.Repeat("A", 14*1024*1024)
+	_, err := decodeBase64Content(huge)
+	if err == nil {
+		t.Fatal("expected error for oversized content")
+	}
+	if !strings.Contains(err.Error(), "too large") {
+		t.Errorf("expected 'too large' error, got: %v", err)
+	}
+}

github/helpers_test.go

@@ -0,0 +1,23 @@
+package github
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+)
+
+// newTestClient creates a *Client backed by an httptest.Server running the
+// given handler. The server is automatically closed when the test finishes.
+// Shared across test files in package github.
+func newTestClient(t *testing.T, handler http.HandlerFunc) *Client {
+	t.Helper()
+	srv := httptest.NewServer(handler)
+	t.Cleanup(srv.Close)
+	c := NewClient("test-token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+	if err := c.SetRetryBackoff([]time.Duration{1 * time.Millisecond, 1 * time.Millisecond}); err != nil {
+		t.Fatalf("SetRetryBackoff: %v", err)
+	}
+	return c
+}

github/identity.go

@@ -0,0 +1,29 @@
+package github
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+)
+
+// userResponse is the GitHub API response for the authenticated user.
+type userResponse struct {
+	Login string `json:"login"`
+}
+
+// GetAuthenticatedUser returns the login of the currently authenticated user.
+func (c *Client) GetAuthenticatedUser(ctx context.Context) (string, error) {
+	reqURL := fmt.Sprintf("%s/user", c.baseURL)
+
+	body, err := c.doGet(ctx, reqURL)
+	if err != nil {
+		return "", fmt.Errorf("get authenticated user: %w", err)
+	}
+
+	var resp userResponse
+	if err := json.Unmarshal(body, &resp); err != nil {
+		return "", fmt.Errorf("parse user response: %w", err)
+	}
+
+	return resp.Login, nil
+}

github/identity_test.go

@@ -0,0 +1,46 @@
+package github
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"testing"
+)
+
+func TestGetAuthenticatedUser_HappyPath(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "GET" {
+			t.Errorf("expected GET, got %s", r.Method)
+		}
+		if r.URL.Path != "/user" {
+			t.Errorf("unexpected path: %s", r.URL.Path)
+		}
+		if r.Header.Get("Authorization") != "Bearer test-token" {
+			t.Errorf("unexpected auth header: %s", r.Header.Get("Authorization"))
+		}
+		json.NewEncoder(w).Encode(map[string]string{"login": "review-bot"})
+	})
+
+	login, err := c.GetAuthenticatedUser(context.Background())
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if login != "review-bot" {
+		t.Errorf("expected login 'review-bot', got %q", login)
+	}
+}
+
+func TestGetAuthenticatedUser_401(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	})
+
+	_, err := c.GetAuthenticatedUser(context.Background())
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+	if !IsUnauthorized(err) {
+		t.Errorf("expected IsUnauthorized=true, got error: %v", err)
+	}
+}

github/pr.go

@@ -0,0 +1,222 @@
+package github
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// pullRequestResponse is the GitHub API response for a pull request.
+type pullRequestResponse struct {
+	Number int    `json:"number"`
+	Title  string `json:"title"`
+	Body   string `json:"body"`
+	Head   struct {
+		SHA string `json:"sha"`
+		Ref string `json:"ref"`
+	} `json:"head"`
+	Base struct {
+		Ref string `json:"ref"`
+	} `json:"base"`
+}
+
+// changedFileResponse is the GitHub API response for a changed file in a PR.
+type changedFileResponse struct {
+	Filename string `json:"filename"`
+	Status   string `json:"status"`
+	Patch    string `json:"patch"`
+}
+
+// commitStatusResponse is the GitHub combined status API response.
+type commitStatusResponse struct {
+	Statuses []struct {
+		Context     string `json:"context"`
+		State       string `json:"state"`
+		Description string `json:"description"`
+		TargetURL   string `json:"target_url"`
+	} `json:"statuses"`
+}
+
+// checkRunsResponse is the GitHub check runs API response.
+type checkRunsResponse struct {
+	CheckRuns []struct {
+		Name       string  `json:"name"`
+		Conclusion *string `json:"conclusion"`
+		Status     string  `json:"status"`
+		HTMLURL    string  `json:"html_url"`
+	} `json:"check_runs"`
+}
+
+// GetPullRequest fetches PR metadata from the GitHub API.
+// Returns an *APIError wrapping the HTTP status on non-2xx responses (e.g.
+// IsNotFound for 404, IsUnauthorized for 401). Network and context errors
+// are wrapped but not typed as *APIError.
+func (c *Client) GetPullRequest(ctx context.Context, owner, repo string, number int) (*vcs.PullRequest, error) {
+	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d", c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
+	body, err := c.doGet(ctx, reqURL)
+	if err != nil {
+		return nil, fmt.Errorf("fetch PR: %w", err)
+	}
+	var resp pullRequestResponse
+	if err := json.Unmarshal(body, &resp); err != nil {
+		return nil, fmt.Errorf("parse PR JSON: %w", err)
+	}
+	return &vcs.PullRequest{
+		Number: resp.Number,
+		Title:  resp.Title,
+		Body:   resp.Body,
+		Head:   vcs.HeadRef{SHA: resp.Head.SHA, Ref: resp.Head.Ref},
+		Base:   vcs.BaseRef{Ref: resp.Base.Ref},
+	}, nil
+}
+
+// GetPullRequestDiff fetches the unified diff for a PR.
+// Uses Accept: application/vnd.github.diff to get raw diff text.
+func (c *Client) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
+	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d", c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
+	body, err := c.doRequest(ctx, http.MethodGet, reqURL, "application/vnd.github.diff")
+	if err != nil {
+		return "", fmt.Errorf("fetch diff: %w", err)
+	}
+	return string(body), nil
+}
+
+const (
+	// maxFilesPages is the upper bound on pagination loops for PR file listing,
+	// preventing unbounded iteration if the server always returns a full page.
+	maxFilesPages = 100
+
+	// maxCheckRunPages is the upper bound on pagination loops for check-run listing,
+	// preventing unbounded iteration if the server always returns a full page.
+	maxCheckRunPages = 100
+)
+
+// GetPullRequestFiles fetches the list of files changed in a PR.
+// Paginates through all pages (100 per page) to collect all files.
+// Returns nil (not an empty slice) when the PR has no changed files.
+// Callers can safely range over or check len() on a nil slice.
+func (c *Client) GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]vcs.ChangedFile, error) {
+	var allFiles []vcs.ChangedFile
+
+	for page := 1; page <= maxFilesPages; page++ {
+		reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/files?per_page=100&page=%d",
+			c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number, page)
+		body, err := c.doGet(ctx, reqURL)
+		if err != nil {
+			return nil, fmt.Errorf("fetch PR files page %d: %w", page, err)
+		}
+		var files []changedFileResponse
+		if err := json.Unmarshal(body, &files); err != nil {
+			return nil, fmt.Errorf("parse PR files JSON: %w", err)
+		}
+		if len(files) == 0 {
+			break
+		}
+		for _, f := range files {
+			allFiles = append(allFiles, vcs.ChangedFile{
+				Filename: f.Filename,
+				Status:   f.Status,
+				Patch:    f.Patch,
+			})
+		}
+		if len(files) < 100 {
+			break
+		}
+	}
+
+	return allFiles, nil
+}
+
+// GetCommitStatuses fetches both commit statuses and check runs for a SHA,
+// merging them into a unified []vcs.CommitStatus slice.
+// Returns nil (not an empty slice) when there are no statuses or check runs.
+// If the commit statuses endpoint fails (e.g. 404 for an unknown SHA), the
+// function returns immediately without attempting the check-runs endpoint.
+// If the check-runs endpoint fails after statuses were fetched successfully,
+// the function returns an error (not a partial result) so callers always get
+// either a complete view or a clear error signal.
+func (c *Client) GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]vcs.CommitStatus, error) {
+	var result []vcs.CommitStatus
+
+	// Fetch commit statuses
+	statusURL := fmt.Sprintf("%s/repos/%s/%s/commits/%s/status",
+		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), url.PathEscape(sha))
+	statusBody, err := c.doGet(ctx, statusURL)
+	if err != nil {
+		return nil, fmt.Errorf("fetch commit statuses: %w", err)
+	}
+	var statusResp commitStatusResponse
+	if err := json.Unmarshal(statusBody, &statusResp); err != nil {
+		return nil, fmt.Errorf("parse commit statuses JSON: %w", err)
+	}
+	for _, s := range statusResp.Statuses {
+		result = append(result, vcs.CommitStatus{
+			Context:     s.Context,
+			Status:      s.State,
+			Description: s.Description,
+			TargetURL:   s.TargetURL,
+		})
+	}
+
+	// Fetch check runs (paginated)
+	for checkPage := 1; checkPage <= maxCheckRunPages; checkPage++ {
+		checkURL := fmt.Sprintf("%s/repos/%s/%s/commits/%s/check-runs?per_page=100&page=%d",
+			c.baseURL, url.PathEscape(owner), url.PathEscape(repo), url.PathEscape(sha), checkPage)
+		checkBody, err := c.doGet(ctx, checkURL)
+		if err != nil {
+			return nil, fmt.Errorf("fetch check runs page %d: %w", checkPage, err)
+		}
+		var checkResp checkRunsResponse
+		if err := json.Unmarshal(checkBody, &checkResp); err != nil {
+			return nil, fmt.Errorf("parse check runs JSON: %w", err)
+		}
+		for _, cr := range checkResp.CheckRuns {
+			result = append(result, vcs.CommitStatus{
+				Context:     cr.Name,
+				Status:      mapCheckRunStatus(cr.Conclusion),
+				Description: "", // check runs have no human-readable description; conclusion is captured in Status
+				TargetURL:   cr.HTMLURL,
+			})
+		}
+		if len(checkResp.CheckRuns) < 100 {
+			break
+		}
+	}
+
+	return result, nil
+}
+
+// mapCheckRunStatus maps a GitHub check run conclusion to a vcs.CommitStatus status string.
+// Conclusion alone determines the mapped state: nil conclusion means the run is
+// still in progress (pending), regardless of the status field value.
+//
+// Mapping rules:
+//   - nil → "pending" (run still in progress or queued)
+//   - "success" → "success"
+//   - "failure", "action_required", "timed_out" → "failure"
+//   - "cancelled", "skipped", "neutral" → "success" (non-blocking per GitHub check suite semantics)
+//   - "stale" → "pending" (check run became stale before completing)
+//   - unknown values → "pending" (conservative: treat unrecognized conclusions as incomplete)
+func mapCheckRunStatus(conclusion *string) string {
+	if conclusion == nil {
+		// Still running or queued
+		return "pending"
+	}
+	switch *conclusion {
+	case "success":
+		return "success"
+	case "failure", "action_required", "timed_out":
+		return "failure"
+	case "cancelled", "skipped", "neutral":
+		return "success" // non-blocking: these do not indicate a blocking failure per GitHub check suite semantics
+	case "stale":
+		return "pending"
+	default:
+		return "pending"
+	}
+}
+

github/pr_test.go

@@ -0,0 +1,676 @@
+package github
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestGetPullRequest_HappyPath(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/repos/owner/repo/pulls/42" {
+			t.Errorf("unexpected path: %s", r.URL.Path)
+		}
+		json.NewEncoder(w).Encode(map[string]interface{}{
+			"number": 42,
+			"title":  "Test PR",
+			"body":   "Description",
+			"head":   map[string]string{"sha": "abc123", "ref": "feature-branch"},
+			"base":   map[string]string{"ref": "main"},
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	pr, err := c.GetPullRequest(context.Background(), "owner", "repo", 42)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if pr.Number != 42 {
+		t.Errorf("expected number 42, got %d", pr.Number)
+	}
+	if pr.Title != "Test PR" {
+		t.Errorf("expected title 'Test PR', got %q", pr.Title)
+	}
+	if pr.Body != "Description" {
+		t.Errorf("expected body 'Description', got %q", pr.Body)
+	}
+	if pr.Head.SHA != "abc123" {
+		t.Errorf("expected head SHA 'abc123', got %q", pr.Head.SHA)
+	}
+	if pr.Head.Ref != "feature-branch" {
+		t.Errorf("expected head ref 'feature-branch', got %q", pr.Head.Ref)
+	}
+	if pr.Base.Ref != "main" {
+		t.Errorf("expected base ref 'main', got %q", pr.Base.Ref)
+	}
+}
+
+func TestGetPullRequest_404(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetPullRequest(context.Background(), "owner", "repo", 999)
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+	if !IsNotFound(err) {
+		t.Errorf("expected IsNotFound=true, got error: %v", err)
+	}
+}
+
+func TestGetPullRequest_401(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetPullRequest(context.Background(), "owner", "repo", 1)
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+	if !IsUnauthorized(err) {
+		t.Errorf("expected IsUnauthorized=true, got error: %v", err)
+	}
+}
+
+func TestGetPullRequest_429Retry(t *testing.T) {
+	attempts := 0
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		attempts++
+		if attempts == 1 {
+			w.WriteHeader(429)
+			w.Write([]byte(`{"message":"rate limit"}`))
+			return
+		}
+		json.NewEncoder(w).Encode(map[string]interface{}{
+			"number": 1,
+			"title":  "PR",
+			"body":   "",
+			"head":   map[string]string{"sha": "abc", "ref": "br"},
+			"base":   map[string]string{"ref": "main"},
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+	c.SetRetryBackoff([]time.Duration{1 * time.Millisecond})
+
+	pr, err := c.GetPullRequest(context.Background(), "owner", "repo", 1)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if pr.Number != 1 {
+		t.Errorf("expected number 1, got %d", pr.Number)
+	}
+	if attempts != 2 {
+		t.Errorf("expected 2 attempts, got %d", attempts)
+	}
+}
+
+func TestGetPullRequest_MalformedJSON(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(200)
+		w.Write([]byte(`{invalid json`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetPullRequest(context.Background(), "owner", "repo", 1)
+	if err == nil {
+		t.Fatal("expected error for malformed JSON")
+	}
+	if !strings.Contains(err.Error(), "parse PR JSON") {
+		t.Errorf("expected parse error, got: %v", err)
+	}
+}
+
+func TestGetPullRequestDiff_HappyPath(t *testing.T) {
+	expectedDiff := "diff --git a/file.go b/file.go\n--- a/file.go\n+++ b/file.go\n@@ -1,3 +1,4 @@\n+// new line\n"
+	var gotAccept string
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		gotAccept = r.Header.Get("Accept")
+		w.WriteHeader(200)
+		w.Write([]byte(expectedDiff))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	diff, err := c.GetPullRequestDiff(context.Background(), "owner", "repo", 42)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if diff != expectedDiff {
+		t.Errorf("unexpected diff: %q", diff)
+	}
+	if gotAccept != "application/vnd.github.diff" {
+		t.Errorf("expected diff Accept header, got %q", gotAccept)
+	}
+}
+
+func TestGetPullRequestDiff_404(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetPullRequestDiff(context.Background(), "owner", "repo", 999)
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+}
+
+func TestGetPullRequestDiff_401(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetPullRequestDiff(context.Background(), "owner", "repo", 1)
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+}
+
+func TestGetPullRequestFiles_HappyPath(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		json.NewEncoder(w).Encode([]map[string]interface{}{
+			{"filename": "main.go", "status": "modified", "patch": "@@ -1,3 +1,4 @@\n+line"},
+			{"filename": "test.go", "status": "added", "patch": "@@ -0,0 +1,5 @@\n+new file"},
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	files, err := c.GetPullRequestFiles(context.Background(), "owner", "repo", 1)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(files) != 2 {
+		t.Fatalf("expected 2 files, got %d", len(files))
+	}
+	if files[0].Filename != "main.go" {
+		t.Errorf("expected filename 'main.go', got %q", files[0].Filename)
+	}
+	if files[0].Status != "modified" {
+		t.Errorf("expected status 'modified', got %q", files[0].Status)
+	}
+	if files[0].Patch != "@@ -1,3 +1,4 @@\n+line" {
+		t.Errorf("unexpected patch: %q", files[0].Patch)
+	}
+}
+
+func TestGetPullRequestFiles_Pagination(t *testing.T) {
+	// Simulate > 100 files requiring pagination
+	page1Files := make([]map[string]string, 100)
+	for i := 0; i < 100; i++ {
+		page1Files[i] = map[string]string{
+			"filename": fmt.Sprintf("file%d.go", i),
+			"status":   "modified",
+			"patch":    fmt.Sprintf("patch%d", i),
+		}
+	}
+	page2Files := []map[string]string{
+		{"filename": "file100.go", "status": "added", "patch": "patch100"},
+	}
+
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		page := r.URL.Query().Get("page")
+		if page == "" || page == "1" {
+			json.NewEncoder(w).Encode(page1Files)
+		} else {
+			json.NewEncoder(w).Encode(page2Files)
+		}
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	files, err := c.GetPullRequestFiles(context.Background(), "owner", "repo", 1)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(files) != 101 {
+		t.Errorf("expected 101 files (paginated), got %d", len(files))
+	}
+	if files[100].Filename != "file100.go" {
+		t.Errorf("expected last file 'file100.go', got %q", files[100].Filename)
+	}
+	if files[100].Patch != "patch100" {
+		t.Errorf("expected last patch 'patch100', got %q", files[100].Patch)
+	}
+}
+
+func TestGetPullRequestFiles_BinaryFile_NoPatch(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Binary files have no patch field in GitHub response
+		json.NewEncoder(w).Encode([]map[string]interface{}{
+			{"filename": "image.png", "status": "added"},
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	files, err := c.GetPullRequestFiles(context.Background(), "owner", "repo", 1)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(files) != 1 {
+		t.Fatalf("expected 1 file, got %d", len(files))
+	}
+	if files[0].Patch != "" {
+		t.Errorf("expected empty patch for binary file, got %q", files[0].Patch)
+	}
+}
+
+func TestGetPullRequestFiles_404(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetPullRequestFiles(context.Background(), "owner", "repo", 999)
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+}
+
+func TestGetPullRequestFiles_MalformedJSON(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(200)
+		w.Write([]byte(`not json`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetPullRequestFiles(context.Background(), "owner", "repo", 1)
+	if err == nil {
+		t.Fatal("expected error for malformed JSON")
+	}
+}
+
+func TestGetFileContentAtRef_HappyPath(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/repos/owner/repo/contents/path/to/file.go" {
+			t.Errorf("unexpected path: %s", r.URL.Path)
+		}
+		if r.URL.Query().Get("ref") != "abc123" {
+			t.Errorf("unexpected ref: %s", r.URL.Query().Get("ref"))
+		}
+		json.NewEncoder(w).Encode(map[string]string{
+			"content":  "cGFja2FnZSBtYWlu", // "package main" in base64
+			"encoding": "base64",
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	content, err := c.GetFileContentAtRef(context.Background(), "owner", "repo", "path/to/file.go", "abc123")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if content != "package main" {
+		t.Errorf("expected 'package main', got %q", content)
+	}
+}
+
+func TestGetFileContentAtRef_EmptyRef(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Query().Get("ref") != "" {
+			t.Errorf("expected no ref param, got %q", r.URL.Query().Get("ref"))
+		}
+		json.NewEncoder(w).Encode(map[string]string{
+			"content":  "aGVsbG8=", // "hello" in base64
+			"encoding": "base64",
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	content, err := c.GetFileContentAtRef(context.Background(), "owner", "repo", "file.txt", "")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if content != "hello" {
+		t.Errorf("expected 'hello', got %q", content)
+	}
+}
+
+func TestGetFileContentAtRef_404(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetFileContentAtRef(context.Background(), "owner", "repo", "missing.go", "main")
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+}
+
+func TestGetFileContentAtRef_401(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetFileContentAtRef(context.Background(), "owner", "repo", "file.go", "main")
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+}
+
+func TestGetFileContentAtRef_MalformedJSON(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(200)
+		w.Write([]byte(`not valid json`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetFileContentAtRef(context.Background(), "owner", "repo", "file.go", "main")
+	if err == nil {
+		t.Fatal("expected error for malformed JSON")
+	}
+}
+
+func TestGetFileContentAtRef_429Retry(t *testing.T) {
+	attempts := 0
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		attempts++
+		if attempts == 1 {
+			w.WriteHeader(429)
+			w.Write([]byte(`{"message":"rate limit"}`))
+			return
+		}
+		json.NewEncoder(w).Encode(map[string]string{
+			"content":  "b2s=", // "ok" in base64
+			"encoding": "base64",
+		})
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+	c.SetRetryBackoff([]time.Duration{1 * time.Millisecond})
+
+	content, err := c.GetFileContentAtRef(context.Background(), "owner", "repo", "file.go", "main")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if content != "ok" {
+		t.Errorf("expected 'ok', got %q", content)
+	}
+	if attempts != 2 {
+		t.Errorf("expected 2 attempts, got %d", attempts)
+	}
+}
+
+func TestGetCommitStatuses_HappyPath(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch {
+		case strings.Contains(r.URL.Path, "/status"):
+			json.NewEncoder(w).Encode(map[string]interface{}{
+				"state": "success",
+				"statuses": []map[string]string{
+					{
+						"context":     "ci/build",
+						"state":       "success",
+						"description": "Build passed",
+						"target_url":  "https://ci.example.com/1",
+					},
+				},
+			})
+		case strings.Contains(r.URL.Path, "/check-runs"):
+			conclusion := "success"
+			json.NewEncoder(w).Encode(map[string]interface{}{
+				"total_count": 1,
+				"check_runs": []map[string]interface{}{
+					{
+						"name":       "lint",
+						"conclusion": &conclusion,
+						"status":     "completed",
+						"html_url":   "https://github.com/check/1",
+					},
+				},
+			})
+		default:
+			t.Errorf("unexpected path: %s", r.URL.Path)
+			w.WriteHeader(404)
+		}
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	statuses, err := c.GetCommitStatuses(context.Background(), "owner", "repo", "abc123")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(statuses) != 2 {
+		t.Fatalf("expected 2 statuses, got %d", len(statuses))
+	}
+	// First should be from commit statuses
+	if statuses[0].Context != "ci/build" {
+		t.Errorf("expected context 'ci/build', got %q", statuses[0].Context)
+	}
+	if statuses[0].Status != "success" {
+		t.Errorf("expected status 'success', got %q", statuses[0].Status)
+	}
+	// Second should be from check runs
+	if statuses[1].Context != "lint" {
+		t.Errorf("expected context 'lint', got %q", statuses[1].Context)
+	}
+	if statuses[1].Status != "success" {
+		t.Errorf("expected status 'success', got %q", statuses[1].Status)
+	}
+}
+
+func TestGetCommitStatuses_CheckRunConclusions(t *testing.T) {
+	tests := []struct {
+		conclusion *string
+		status     string
+		want       string
+	}{
+		{stringPtr("success"), "completed", "success"},
+		{stringPtr("failure"), "completed", "failure"},
+		{stringPtr("action_required"), "completed", "failure"},
+		{stringPtr("timed_out"), "completed", "failure"},
+		{stringPtr("cancelled"), "completed", "success"},
+		{stringPtr("skipped"), "completed", "success"},
+		{stringPtr("neutral"), "completed", "success"},
+		{nil, "in_progress", "pending"},
+		{nil, "queued", "pending"},
+	}
+
+	for _, tt := range tests {
+		name := "nil"
+		if tt.conclusion != nil {
+			name = *tt.conclusion
+		}
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+			srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				if strings.Contains(r.URL.Path, "/status") {
+					json.NewEncoder(w).Encode(map[string]interface{}{
+						"state":    "success",
+						"statuses": []interface{}{},
+					})
+					return
+				}
+				json.NewEncoder(w).Encode(map[string]interface{}{
+					"total_count": 1,
+					"check_runs": []map[string]interface{}{
+						{
+							"name":       "check",
+							"conclusion": tt.conclusion,
+							"status":     tt.status,
+							"html_url":   "https://github.com/check/1",
+						},
+					},
+				})
+			}))
+			defer srv.Close()
+
+			c := NewClient("token", srv.URL, AllowInsecureHTTP())
+			c.SetHTTPClient(srv.Client())
+
+			statuses, err := c.GetCommitStatuses(context.Background(), "owner", "repo", "sha1")
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if len(statuses) != 1 {
+				t.Fatalf("expected 1 status, got %d", len(statuses))
+			}
+			if statuses[0].Status != tt.want {
+				t.Errorf("expected status %q, got %q", tt.want, statuses[0].Status)
+			}
+		})
+	}
+}
+
+func TestGetCommitStatuses_404(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetCommitStatuses(context.Background(), "owner", "repo", "badsha")
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+}
+
+func TestGetCommitStatuses_401(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetCommitStatuses(context.Background(), "owner", "repo", "sha")
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+}
+
+func TestGetCommitStatuses_MalformedJSON(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(200)
+		w.Write([]byte(`not json`))
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetCommitStatuses(context.Background(), "owner", "repo", "sha")
+	if err == nil {
+		t.Fatal("expected error for malformed JSON")
+	}
+}
+
+func TestGetCommitStatuses_CheckRunsErrorAfterStatusesSucceed(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		switch {
+		case strings.Contains(r.URL.Path, "/status"):
+			// Statuses succeed
+			json.NewEncoder(w).Encode(map[string]interface{}{
+				"state": "success",
+				"statuses": []map[string]string{
+					{
+						"context":     "ci/build",
+						"state":       "success",
+						"description": "Build passed",
+						"target_url":  "https://ci.example.com/1",
+					},
+				},
+			})
+		case strings.Contains(r.URL.Path, "/check-runs"):
+			// Check runs fail with 500
+			w.WriteHeader(500)
+			w.Write([]byte(`{"message":"Internal Server Error"}`))
+		default:
+			w.WriteHeader(404)
+		}
+	}))
+	defer srv.Close()
+
+	c := NewClient("token", srv.URL, AllowInsecureHTTP())
+	c.SetHTTPClient(srv.Client())
+
+	_, err := c.GetCommitStatuses(context.Background(), "owner", "repo", "abc123")
+	if err == nil {
+		t.Fatal("expected error when check-runs endpoint fails after statuses succeed")
+	}
+	if !strings.Contains(err.Error(), "fetch check runs") {
+		t.Errorf("expected check runs error, got: %v", err)
+	}
+}
+
+func stringPtr(s string) *string {
+	return &s
+}

github/review.go

@@ -0,0 +1,230 @@
+package github
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// ErrCannotDeleteSubmittedReview is returned when DeleteReview is called on
+// a review that has already been submitted (APPROVED, REQUEST_CHANGES, COMMENT).
+// GitHub only allows deletion of PENDING reviews. Callers that need to replace
+// a submitted review should use DismissReview instead.
+var ErrCannotDeleteSubmittedReview = errors.New("cannot delete submitted review: use DismissReview instead")
+
+// ErrConflictingCommitIDs is returned when PostReview receives comments with
+// differing non-empty CommitIDs. The GitHub API accepts only a single commit_id
+// per review submission; callers must ensure all comments target the same commit.
+var ErrConflictingCommitIDs = errors.New("comments contain conflicting commit IDs: all must target the same commit")
+
+// postReviewRequest is the GitHub API request body for creating a review.
+type postReviewRequest struct {
+	CommitID string               `json:"commit_id,omitempty"`
+	Body     string               `json:"body"`
+	Event    string               `json:"event"`
+	Comments []reviewCommentEntry `json:"comments,omitempty"`
+}
+
+// reviewCommentEntry is a single inline comment in a review creation request.
+type reviewCommentEntry struct {
+	Path     string `json:"path"`
+	Position int    `json:"position"`
+	Body     string `json:"body"`
+}
+
+// reviewResponse is the GitHub API response for a review.
+type reviewResponse struct {
+	ID       int64  `json:"id"`
+	Body     string `json:"body"`
+	State    string `json:"state"`
+	CommitID string `json:"commit_id"`
+	User     struct {
+		Login string `json:"login"`
+	} `json:"user"`
+}
+
+// dismissReviewRequest is the GitHub API request body for dismissing a review.
+type dismissReviewRequest struct {
+	Message string `json:"message"`
+	Event   string `json:"event"`
+}
+
+// translateGitHubReviewState translates a GitHub API review state to the
+// canonical vcs.Review.State value.
+func translateGitHubReviewState(state string) string {
+	switch state {
+	case "CHANGES_REQUESTED":
+		return "REQUEST_CHANGES"
+	case "COMMENTED":
+		return "COMMENT"
+	default:
+		// States like APPROVED, DISMISSED, and PENDING pass through unchanged
+		// as they already match the canonical vcs representation. PENDING appears
+		// on draft reviews that have not yet been submitted via the GitHub UI or API.
+		return state
+	}
+}
+
+// PostReview submits a review on a pull request.
+//
+// The vcs.ReviewEvent constants (ReviewEventApprove, ReviewEventRequestChanges,
+// ReviewEventComment) have string values that match GitHub's wire-format event
+// strings (APPROVE, REQUEST_CHANGES, COMMENT), so Event is cast directly to
+// string without translation.
+//
+// ReviewComment.Position maps directly to the GitHub API position field.
+// When req.Comments is empty, the payload omits the comments field entirely
+// (via the omitempty tag on postReviewRequest.Comments).
+//
+// The GitHub API accepts a single commit_id per review submission. PostReview
+// uses req.CommitID as the primary commit anchor. If req.CommitID is empty,
+// it falls back to extracting from the first comment with a non-empty CommitID.
+// If any subsequent comment specifies a different CommitID, PostReview returns
+// ErrConflictingCommitIDs. Comments with an empty CommitID are allowed and
+// inherit the review-level value.
+func (c *Client) PostReview(ctx context.Context, owner, repo string, number int, req vcs.ReviewRequest) (*vcs.Review, error) {
+	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/reviews",
+		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
+
+	payload := postReviewRequest{
+		Body:     req.Body,
+		Event:    string(req.Event),
+		CommitID: req.CommitID,
+	}
+
+	// Build the payload in one pass. The GitHub API accepts a single commit_id
+	// per review. req.CommitID is the primary source; if empty, we extract from
+	// the first comment that supplies one. Reject if any comment disagrees with
+	// the resolved commit_id.
+	for _, comment := range req.Comments {
+		if comment.CommitID != "" {
+			if payload.CommitID == "" { // only reachable when req.CommitID is empty
+				payload.CommitID = comment.CommitID
+			} else if payload.CommitID != comment.CommitID {
+				return nil, ErrConflictingCommitIDs
+			}
+			// else: matching SHA is a no-op by design
+		}
+		payload.Comments = append(payload.Comments, reviewCommentEntry{
+			Path:     comment.Path,
+			Position: comment.Position,
+			Body:     comment.Body,
+		})
+	}
+
+	data, err := json.Marshal(payload)
+	if err != nil {
+		return nil, fmt.Errorf("marshal review request: %w", err)
+	}
+
+	body, err := c.doRequestWithBody(ctx, http.MethodPost, reqURL, data)
+	if err != nil {
+		return nil, fmt.Errorf("post review: %w", err)
+	}
+
+	var resp reviewResponse
+	if err := json.Unmarshal(body, &resp); err != nil {
+		return nil, fmt.Errorf("parse review response: %w", err)
+	}
+
+	return &vcs.Review{
+		ID:       resp.ID,
+		Body:     resp.Body,
+		User:     vcs.UserInfo{Login: resp.User.Login},
+		State:    translateGitHubReviewState(resp.State),
+		CommitID: resp.CommitID,
+	}, nil
+}
+
+// ListReviews retrieves all reviews for a pull request.
+// GitHub review states are translated to canonical vcs values.
+func (c *Client) ListReviews(ctx context.Context, owner, repo string, number int) ([]vcs.Review, error) {
+	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/reviews",
+		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
+
+	body, err := c.doGet(ctx, reqURL)
+	if err != nil {
+		return nil, fmt.Errorf("list reviews: %w", err)
+	}
+
+	var responses []reviewResponse
+	if err := json.Unmarshal(body, &responses); err != nil {
+		return nil, fmt.Errorf("parse reviews response: %w", err)
+	}
+
+	reviews := make([]vcs.Review, len(responses))
+	for i, r := range responses {
+		reviews[i] = vcs.Review{
+			ID:       r.ID,
+			Body:     r.Body,
+			User:     vcs.UserInfo{Login: r.User.Login},
+			State:    translateGitHubReviewState(r.State),
+			CommitID: r.CommitID,
+		}
+	}
+	return reviews, nil
+}
+
+// DeleteReview deletes a pull request review.
+// Only PENDING reviews can be deleted; attempting to delete a submitted review
+// (APPROVED, CHANGES_REQUESTED, or COMMENTED per GitHub API naming) returns
+// ErrCannotDeleteSubmittedReview.
+func (c *Client) DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error {
+	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/reviews/%d",
+		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number, reviewID)
+
+	// nil body: the GitHub DELETE endpoint for reviews requires no request body.
+	_, err := c.doRequestWithBody(ctx, http.MethodDelete, reqURL, nil)
+	if err != nil {
+		var apiErr *APIError
+		if errors.As(err, &apiErr) && apiErr.StatusCode == 422 {
+			return fmt.Errorf("delete review: %w", ErrCannotDeleteSubmittedReview)
+		}
+		return fmt.Errorf("delete review: %w", err)
+	}
+	return nil
+}
+
+// DismissReview dismisses a submitted review on a pull request.
+// This is the correct way to "remove" a submitted review (APPROVED, REQUEST_CHANGES).
+// GitHub does not allow deleting submitted reviews — they must be dismissed.
+func (c *Client) DismissReview(ctx context.Context, owner, repo string, number int, reviewID int64, message string) error {
+	reqURL := fmt.Sprintf("%s/repos/%s/%s/pulls/%d/reviews/%d/dismissals",
+		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number, reviewID)
+
+	payload := dismissReviewRequest{
+		Message: message,
+		// Event is required by the GitHub API for dismissal requests, even though
+		// "DISMISS" is the only valid value for this endpoint.
+		Event: "DISMISS",
+	}
+
+	data, err := json.Marshal(payload)
+	if err != nil {
+		return fmt.Errorf("marshal dismiss request: %w", err)
+	}
+
+	_, err = c.doRequestWithBody(ctx, http.MethodPut, reqURL, data)
+	if err != nil {
+		return fmt.Errorf("dismiss review: %w", err)
+	}
+	return nil
+}
+
+// SupersedeReviews marks prior reviews as superseded by dismissing them.
+// This implements vcs.ReviewSuperseder for the GitHub adapter.
+// The baseURL and sentinel parameters are unused for GitHub (dismissal is the mechanism).
+func (c *Client) SupersedeReviews(ctx context.Context, owner, repo string, prNumber int, oldReviews []vcs.Review, newReviewID int64, _, _ string) error {
+	var errs []error
+	for _, old := range oldReviews {
+		if err := c.DismissReview(ctx, owner, repo, prNumber, old.ID, "Superseded by new review"); err != nil {
+			errs = append(errs, fmt.Errorf("dismiss review %d: %w", old.ID, err))
+		}
+	}
+	return errors.Join(errs...)
+}

github/review_test.go

@@ -0,0 +1,484 @@
+package github
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// --- PostReview tests ---
+
+func TestPostReview_HappyPath(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "POST" {
+			t.Fatalf("expected POST, got %s", r.Method)
+		}
+		if r.URL.Path != "/repos/owner/repo/pulls/5/reviews" {
+			t.Fatalf("unexpected path: %s", r.URL.Path)
+		}
+		if r.Header.Get("Content-Type") != "application/json" {
+			t.Errorf("expected Content-Type application/json, got %q", r.Header.Get("Content-Type"))
+		}
+
+		// Verify request body
+		body, _ := io.ReadAll(r.Body)
+		var req postReviewRequest
+		if err := json.Unmarshal(body, &req); err != nil {
+			t.Fatalf("unmarshal request: %v", err)
+		}
+		if req.Event != "APPROVE" {
+			t.Errorf("expected event APPROVE, got %q", req.Event)
+		}
+		if req.Body != "LGTM" {
+			t.Errorf("expected body 'LGTM', got %q", req.Body)
+		}
+		if req.CommitID != "abc123" {
+			t.Errorf("expected commit_id 'abc123', got %q", req.CommitID)
+		}
+		if len(req.Comments) != 1 {
+			t.Fatalf("expected 1 comment, got %d", len(req.Comments))
+		}
+		if req.Comments[0].Path != "main.go" {
+			t.Errorf("expected comment path 'main.go', got %q", req.Comments[0].Path)
+		}
+		if req.Comments[0].Position != 4 {
+			t.Errorf("expected comment position 4, got %d", req.Comments[0].Position)
+		}
+
+		json.NewEncoder(w).Encode(map[string]interface{}{
+			"id":        100,
+			"body":      "LGTM",
+			"state":     "APPROVED",
+			"commit_id": "abc123",
+			"user":      map[string]string{"login": "reviewer"},
+		})
+	})
+
+	review, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
+		Body:  "LGTM",
+		Event: vcs.ReviewEventApprove,
+		Comments: []vcs.ReviewComment{
+			{Path: "main.go", Position: 4, CommitID: "abc123", Body: "nit: rename"},
+		},
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if review.ID != 100 {
+		t.Errorf("expected ID 100, got %d", review.ID)
+	}
+	if review.Body != "LGTM" {
+		t.Errorf("expected body 'LGTM', got %q", review.Body)
+	}
+	if review.State != "APPROVED" {
+		t.Errorf("expected state 'APPROVED', got %q", review.State)
+	}
+	if review.User.Login != "reviewer" {
+		t.Errorf("expected user 'reviewer', got %q", review.User.Login)
+	}
+	if review.CommitID != "abc123" {
+		t.Errorf("expected commit_id 'abc123', got %q", review.CommitID)
+	}
+}
+
+func TestPostReview_401(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	})
+
+	_, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
+		Body:  "LGTM",
+		Event: vcs.ReviewEventApprove,
+	})
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+	if !IsUnauthorized(err) {
+		t.Errorf("expected IsUnauthorized=true, got error: %v", err)
+	}
+}
+
+func TestPostReview_422(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(422)
+		w.Write([]byte(`{"message":"Unprocessable Entity"}`))
+	})
+
+	_, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
+		Body:  "LGTM",
+		Event: vcs.ReviewEventApprove,
+	})
+	if err == nil {
+		t.Fatal("expected error for 422")
+	}
+	// 422 should surface as a wrapped APIError
+	var apiErr *APIError
+	if !errors.As(err, &apiErr) {
+		t.Fatalf("expected *APIError, got %T: %v", err, err)
+	}
+	if apiErr.StatusCode != 422 {
+		t.Errorf("expected status 422, got %d", apiErr.StatusCode)
+	}
+}
+
+func TestPostReview_MalformedResponse(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte(`not json`))
+	})
+
+	_, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
+		Body:  "LGTM",
+		Event: vcs.ReviewEventApprove,
+	})
+	if err == nil {
+		t.Fatal("expected error for malformed response")
+	}
+	if !strings.Contains(err.Error(), "parse review response") {
+		t.Errorf("expected parse error, got: %v", err)
+	}
+}
+
+// --- ListReviews tests ---
+
+func TestListReviews_HappyPath(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "GET" {
+			t.Fatalf("expected GET, got %s", r.Method)
+		}
+		if r.URL.Path != "/repos/owner/repo/pulls/3/reviews" {
+			t.Fatalf("unexpected path: %s", r.URL.Path)
+		}
+		json.NewEncoder(w).Encode([]map[string]interface{}{
+			{
+				"id":        1,
+				"body":      "Approved",
+				"state":     "APPROVED",
+				"commit_id": "sha1",
+				"user":      map[string]string{"login": "user1"},
+			},
+			{
+				"id":        2,
+				"body":      "Needs work",
+				"state":     "CHANGES_REQUESTED",
+				"commit_id": "sha2",
+				"user":      map[string]string{"login": "user2"},
+			},
+			{
+				"id":        3,
+				"body":      "Comment only",
+				"state":     "COMMENTED",
+				"commit_id": "sha3",
+				"user":      map[string]string{"login": "user3"},
+			},
+			{
+				"id":        4,
+				"body":      "Old review",
+				"state":     "DISMISSED",
+				"commit_id": "sha4",
+				"user":      map[string]string{"login": "user4"},
+			},
+		})
+	})
+
+	reviews, err := c.ListReviews(context.Background(), "owner", "repo", 3)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(reviews) != 4 {
+		t.Fatalf("expected 4 reviews, got %d", len(reviews))
+	}
+
+	// Check state translation
+	expected := []struct {
+		id    int64
+		state string
+	}{
+		{1, "APPROVED"},
+		{2, "REQUEST_CHANGES"},
+		{3, "COMMENT"},
+		{4, "DISMISSED"},
+	}
+	for i, e := range expected {
+		if reviews[i].ID != e.id {
+			t.Errorf("review[%d]: expected ID %d, got %d", i, e.id, reviews[i].ID)
+		}
+		if reviews[i].State != e.state {
+			t.Errorf("review[%d]: expected state %q, got %q", i, e.state, reviews[i].State)
+		}
+	}
+}
+
+func TestListReviews_404(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	})
+
+	_, err := c.ListReviews(context.Background(), "owner", "repo", 999)
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+	if !IsNotFound(err) {
+		t.Errorf("expected IsNotFound=true, got error: %v", err)
+	}
+}
+
+func TestListReviews_401(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	})
+
+	_, err := c.ListReviews(context.Background(), "owner", "repo", 3)
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+	if !IsUnauthorized(err) {
+		t.Errorf("expected IsUnauthorized=true, got error: %v", err)
+	}
+}
+
+// --- DeleteReview tests ---
+
+func TestDeleteReview_HappyPath(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "DELETE" {
+			t.Fatalf("expected DELETE, got %s", r.Method)
+		}
+		if r.URL.Path != "/repos/owner/repo/pulls/5/reviews/42" {
+			t.Fatalf("unexpected path: %s", r.URL.Path)
+		}
+		w.WriteHeader(204)
+	})
+
+	err := c.DeleteReview(context.Background(), "owner", "repo", 5, 42)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}
+
+func TestDeleteReview_422_SubmittedReview(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(422)
+		w.Write([]byte(`{"message":"Can not delete a non pending review"}`))
+	})
+
+	err := c.DeleteReview(context.Background(), "owner", "repo", 5, 42)
+	if err == nil {
+		t.Fatal("expected error for 422")
+	}
+	if !errors.Is(err, ErrCannotDeleteSubmittedReview) {
+		t.Errorf("expected ErrCannotDeleteSubmittedReview, got: %v", err)
+	}
+}
+
+// --- DismissReview tests ---
+
+func TestDismissReview_HappyPath(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "PUT" {
+			t.Fatalf("expected PUT, got %s", r.Method)
+		}
+		if r.URL.Path != "/repos/owner/repo/pulls/5/reviews/10/dismissals" {
+			t.Fatalf("unexpected path: %s", r.URL.Path)
+		}
+
+		body, _ := io.ReadAll(r.Body)
+		var req dismissReviewRequest
+		if err := json.Unmarshal(body, &req); err != nil {
+			t.Fatalf("unmarshal request: %v", err)
+		}
+		if req.Message != "Superseded by new review" {
+			t.Errorf("expected message 'Superseded by new review', got %q", req.Message)
+		}
+		if req.Event != "DISMISS" {
+			t.Errorf("expected event 'DISMISS', got %q", req.Event)
+		}
+
+		json.NewEncoder(w).Encode(map[string]interface{}{
+			"id":    10,
+			"state": "DISMISSED",
+		})
+	})
+
+	err := c.DismissReview(context.Background(), "owner", "repo", 5, 10, "Superseded by new review")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}
+
+func TestDismissReview_404(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(404)
+		w.Write([]byte(`{"message":"Not Found"}`))
+	})
+
+	err := c.DismissReview(context.Background(), "owner", "repo", 5, 999, "dismiss")
+	if err == nil {
+		t.Fatal("expected error for 404")
+	}
+	if !IsNotFound(err) {
+		t.Errorf("expected IsNotFound=true, got error: %v", err)
+	}
+}
+
+func TestDismissReview_401(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(401)
+		w.Write([]byte(`{"message":"Bad credentials"}`))
+	})
+
+	err := c.DismissReview(context.Background(), "owner", "repo", 5, 10, "dismiss")
+	if err == nil {
+		t.Fatal("expected error for 401")
+	}
+	if !IsUnauthorized(err) {
+		t.Errorf("expected IsUnauthorized=true, got error: %v", err)
+	}
+}
+
+// --- State translation tests ---
+
+func TestTranslateGitHubReviewState(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  string
+	}{
+		{"approved passes through", "APPROVED", "APPROVED"},
+		{"changes_requested maps to REQUEST_CHANGES", "CHANGES_REQUESTED", "REQUEST_CHANGES"},
+		{"commented maps to COMMENT", "COMMENTED", "COMMENT"},
+		{"dismissed passes through", "DISMISSED", "DISMISSED"},
+		{"unknown state passes through", "UNKNOWN_STATE", "UNKNOWN_STATE"},
+		{"empty string passes through", "", ""},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := translateGitHubReviewState(tt.input)
+			if got != tt.want {
+				t.Errorf("translateGitHubReviewState(%q) = %q, want %q", tt.input, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestPostReview_ConflictingCommitIDs(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		t.Fatal("request should not be sent when commit IDs conflict")
+	})
+
+	_, err := c.PostReview(context.Background(), "owner", "repo", 5, vcs.ReviewRequest{
+		Body:  "Review",
+		Event: vcs.ReviewEventComment,
+		Comments: []vcs.ReviewComment{
+			{Path: "a.go", Position: 1, CommitID: "sha-1", Body: "first"},
+			{Path: "b.go", Position: 2, CommitID: "sha-2", Body: "second"},
+		},
+	})
+	if err == nil {
+		t.Fatal("expected error for conflicting commit IDs")
+	}
+	if !errors.Is(err, ErrConflictingCommitIDs) {
+		t.Errorf("expected ErrConflictingCommitIDs, got: %v", err)
+	}
+}
+
+func TestPostReview_RequestCommitID_TakesPriority(t *testing.T) {
+	var gotPayload struct {
+		CommitID string `json:"commit_id"`
+		Body     string `json:"body"`
+	}
+
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		json.NewDecoder(r.Body).Decode(&gotPayload)
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":        42,
+			"body":      "LGTM",
+			"state":     "APPROVED",
+			"commit_id": "req-level-sha",
+			"user":      map[string]any{"login": "bot"},
+		})
+	})
+
+	review, err := c.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:     "LGTM",
+		Event:    vcs.ReviewEventApprove,
+		CommitID: "req-level-sha",
+		Comments: []vcs.ReviewComment{
+			{Path: "a.go", Position: 1, CommitID: "req-level-sha", Body: "looks good"},
+		},
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if gotPayload.CommitID != "req-level-sha" {
+		t.Errorf("sent commit_id = %q, want %q", gotPayload.CommitID, "req-level-sha")
+	}
+	if review.CommitID != "req-level-sha" {
+		t.Errorf("review.CommitID = %q, want %q", review.CommitID, "req-level-sha")
+	}
+}
+
+func TestPostReview_RequestCommitID_ConflictsWithComment(t *testing.T) {
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		t.Fatal("request should not be sent when commit IDs conflict")
+	})
+
+	// req.CommitID is set, and a comment has a different CommitID → conflict
+	_, err := c.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:     "Review",
+		Event:    vcs.ReviewEventComment,
+		CommitID: "req-sha",
+		Comments: []vcs.ReviewComment{
+			{Path: "a.go", Position: 1, CommitID: "different-sha", Body: "nit"},
+		},
+	})
+	if err == nil {
+		t.Fatal("expected error for conflicting commit IDs")
+	}
+	if !errors.Is(err, ErrConflictingCommitIDs) {
+		t.Errorf("expected ErrConflictingCommitIDs, got: %v", err)
+	}
+}
+
+func TestPostReview_RequestCommitID_FallbackToComment(t *testing.T) {
+	var gotPayload struct {
+		CommitID string `json:"commit_id"`
+	}
+
+	c := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
+		json.NewDecoder(r.Body).Decode(&gotPayload)
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(map[string]any{
+			"id":        43,
+			"body":      "ok",
+			"state":     "COMMENTED",
+			"commit_id": "comment-sha",
+			"user":      map[string]any{"login": "bot"},
+		})
+	})
+
+	// req.CommitID is empty, so it falls back to the comment's CommitID
+	_, err := c.PostReview(context.Background(), "owner", "repo", 1, vcs.ReviewRequest{
+		Body:  "ok",
+		Event: vcs.ReviewEventComment,
+		// CommitID intentionally empty
+		Comments: []vcs.ReviewComment{
+			{Path: "a.go", Position: 1, CommitID: "comment-sha", Body: "note"},
+		},
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if gotPayload.CommitID != "comment-sha" {
+		t.Errorf("sent commit_id = %q, want %q (fallback from comment)", gotPayload.CommitID, "comment-sha")
+	}
+}

go.mod

@@ -2,4 +2,4 @@ module gitea.weiker.me/rodin/review-bot
 
 go 1.26.2
 
-require github.com/goccy/go-yaml v1.19.2
+require gopkg.in/yaml.v3 v3.0.1

go.sum

@@ -1,2 +1,4 @@
-github.com/goccy/go-yaml v1.19.2 h1:PmFC1S6h8ljIz6gMRBopkjP1TVT7xuwrButHID66PoM=
-github.com/goccy/go-yaml v1.19.2/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

integration_test.go

@@ -16,17 +16,16 @@ import (
 
 // Integration test requires a running Gitea instance and LLM endpoint.
 // Set environment variables:
-//
-//	INTEGRATION_VCS_URL       - VCS base URL
-//	INTEGRATION_GITEA_TOKEN   - Gitea API token with repo access
-//	INTEGRATION_GITEA_REPO    - owner/repo with an open PR
-//	INTEGRATION_PR_NUMBER     - PR number to test against
-//	INTEGRATION_LLM_BASE_URL  - LLM API base URL
-//	INTEGRATION_LLM_API_KEY   - LLM API key
-//	INTEGRATION_LLM_MODEL     - Model name
+//   INTEGRATION_GITEA_URL     - Gitea base URL
+//   INTEGRATION_GITEA_TOKEN   - Gitea API token with repo access
+//   INTEGRATION_GITEA_REPO    - owner/repo with an open PR
+//   INTEGRATION_PR_NUMBER     - PR number to test against
+//   INTEGRATION_LLM_BASE_URL  - LLM API base URL
+//   INTEGRATION_LLM_API_KEY   - LLM API key
+//   INTEGRATION_LLM_MODEL     - Model name
 
 func TestIntegration_FullReviewFlow(t *testing.T) {
-	giteaURL := os.Getenv("INTEGRATION_VCS_URL")
+	giteaURL := os.Getenv("INTEGRATION_GITEA_URL")
 	giteaToken := os.Getenv("INTEGRATION_GITEA_TOKEN")
 	giteaRepo := os.Getenv("INTEGRATION_GITEA_REPO")
 	prNumStr := os.Getenv("INTEGRATION_PR_NUMBER")

internal/netutil/ipcheck.go

@@ -1,97 +0,0 @@
-// Package netutil provides shared network utilities for review-bot.
-// ipcheck.go implements IP-level SSRF protection by checking resolved addresses
-// against known blocked CIDR ranges (RFC1918, loopback, link-local, etc.).
-package netutil
-
-import (
-	"fmt"
-	"net"
-)
-
-// blockedCIDRStrings is the canonical list of CIDR strings that should never
-// be contacted by review-bot. See IsBlockedIP for the full list of covered
-// address families.
-//
-// These are hard-coded literals: any parse failure is a programming error.
-// Validity is verified by TestBlockedCIDRsValid in ipcheck_test.go.
-var blockedCIDRStrings = []string{
-	// IPv4 loopback
-	"127.0.0.0/8",
-	// IPv4 unspecified / "this network"
-	"0.0.0.0/8",
-	// RFC1918 private ranges
-	"10.0.0.0/8",
-	"172.16.0.0/12",
-	"192.168.0.0/16",
-	// IPv4 link-local (APIPA, also used by AWS instance metadata 169.254.169.254)
-	"169.254.0.0/16",
-	// IPv4 shared address space (RFC6598, carrier-grade NAT)
-	"100.64.0.0/10",
-	// IPv4 multicast
-	"224.0.0.0/4",
-	// IPv4 reserved / broadcast
-	"240.0.0.0/4",
-	// IPv6 loopback
-	"::1/128",
-	// IPv6 unspecified
-	"::/128",
-	// IPv6 link-local
-	"fe80::/10",
-	// IPv6 unique local (ULA) — RFC4193
-	"fc00::/7",
-	// IPv6 multicast
-	"ff00::/8",
-}
-
-// blockedCIDRs is the parsed form of blockedCIDRStrings.
-// Any entry that fails to parse is recorded in blockedCIDRParseErrors instead
-// of panicking; tests verify this slice is always empty via TestBlockedCIDRsValid.
-var (
-	blockedCIDRs           []*net.IPNet
-	blockedCIDRParseErrors []string
-)
-
-func init() {
-	blockedCIDRs = make([]*net.IPNet, 0, len(blockedCIDRStrings))
-	for _, r := range blockedCIDRStrings {
-		_, cidr, err := net.ParseCIDR(r)
-		if err != nil {
-			// Record the error rather than panicking; TestBlockedCIDRsValid
-			// will catch this during tests, and the CI build will fail.
-			blockedCIDRParseErrors = append(blockedCIDRParseErrors,
-				fmt.Sprintf("ipcheck: invalid built-in CIDR %q: %v", r, err))
-			continue
-		}
-		blockedCIDRs = append(blockedCIDRs, cidr)
-	}
-}
-
-// BlockedCIDRParseErrors returns any errors encountered parsing the built-in
-// CIDR list. In correct code this will always be empty; tests assert it is.
-func BlockedCIDRParseErrors() []string {
-	return blockedCIDRParseErrors
-}
-
-// IsBlockedIP reports whether ip is in a blocked address range.
-// It is exported for use by the gitea package's safe dialer, the validate-url
-// subcommand, and tests outside this package.
-//
-// IPv6-mapped IPv4 addresses (e.g. ::ffff:192.168.1.1) are normalized to their
-// IPv4 form before checking so that IPv4 CIDRs catch them.
-//
-// Based on:
-//   - RFC1918 private ranges
-//   - RFC5735 / RFC4193 special-use IPv4/IPv6 ranges
-//   - RFC4291 IPv6 link-local / loopback
-func IsBlockedIP(ip net.IP) bool {
-	// Normalize IPv6-mapped IPv4 addresses (::ffff:x.x.x.x) to plain IPv4.
-	if v4 := ip.To4(); v4 != nil {
-		ip = v4
-	}
-	for _, cidr := range blockedCIDRs {
-		if cidr.Contains(ip) {
-			return true
-		}
-	}
-	return false
-}

internal/netutil/ipcheck_test.go

@@ -1,142 +0,0 @@
-package netutil
-
-import (
-	"net"
-	"testing"
-)
-
-func TestIsBlockedIP(t *testing.T) {
-	blocked := []struct {
-		name string
-		ip   string
-	}{
-		// IPv4 loopback
-		{"loopback 127.0.0.1", "127.0.0.1"},
-		{"loopback 127.0.0.2", "127.0.0.2"},
-		{"loopback 127.255.255.255", "127.255.255.255"},
-		// IPv4 unspecified
-		{"unspecified 0.0.0.0", "0.0.0.0"},
-		{"unspecified 0.1.2.3", "0.1.2.3"},
-		// RFC1918
-		{"RFC1918 10.0.0.1", "10.0.0.1"},
-		{"RFC1918 10.255.255.255", "10.255.255.255"},
-		{"RFC1918 172.16.0.1", "172.16.0.1"},
-		{"RFC1918 172.31.255.255", "172.31.255.255"},
-		{"RFC1918 192.168.0.1", "192.168.0.1"},
-		{"RFC1918 192.168.255.255", "192.168.255.255"},
-		// Link-local (APIPA / AWS metadata)
-		{"link-local 169.254.0.1", "169.254.0.1"},
-		{"link-local 169.254.169.254", "169.254.169.254"},
-		// Shared address space (carrier-grade NAT)
-		{"CGN 100.64.0.1", "100.64.0.1"},
-		{"CGN 100.127.255.255", "100.127.255.255"},
-		// Multicast
-		{"multicast 224.0.0.1", "224.0.0.1"},
-		{"multicast 239.255.255.255", "239.255.255.255"},
-		// Reserved
-		{"reserved 240.0.0.1", "240.0.0.1"},
-		{"broadcast 255.255.255.255", "255.255.255.255"},
-		// IPv6 loopback
-		{"IPv6 loopback ::1", "::1"},
-		// IPv6 unspecified
-		{"IPv6 unspecified ::", "::"},
-		// IPv6 link-local
-		{"IPv6 link-local fe80::1", "fe80::1"},
-		{"IPv6 link-local fe80::dead:beef", "fe80::dead:beef"},
-		// IPv6 ULA
-		{"IPv6 ULA fc00::1", "fc00::1"},
-		{"IPv6 ULA fd00::1", "fd00::1"},
-		// IPv6 multicast
-		{"IPv6 multicast ff02::1", "ff02::1"},
-	}
-
-	for _, tc := range blocked {
-		t.Run(tc.name, func(t *testing.T) {
-			ip := net.ParseIP(tc.ip)
-			if ip == nil {
-				t.Fatalf("failed to parse IP %q", tc.ip)
-			}
-			if !IsBlockedIP(ip) {
-				t.Errorf("IsBlockedIP(%q) = false, want true", tc.ip)
-			}
-		})
-	}
-
-	allowed := []struct {
-		name string
-		ip   string
-	}{
-		{"public 8.8.8.8", "8.8.8.8"},
-		{"public 1.1.1.1", "1.1.1.1"},
-		{"public 198.51.100.1", "198.51.100.1"}, // RFC5737 TEST-NET-2 — a documentation-only range;
-		// not assigned to any real host, but intentionally left unblocked here because
-		// it has no special routing treatment (unlike RFC1918/loopback/link-local) and
-		// blocking it would require tracking every RFC5737 range without meaningful
-		// security benefit (no server should ever listen on a TEST-NET address).
-		{"public 151.101.1.1", "151.101.1.1"},                        // Fastly
-		{"public IPv6 2001:4860:4860::8888", "2001:4860:4860::8888"}, // Google DNS
-		{"public IPv6 2606:4700:4700::1111", "2606:4700:4700::1111"}, // Cloudflare DNS
-	}
-
-	for _, tc := range allowed {
-		t.Run(tc.name, func(t *testing.T) {
-			ip := net.ParseIP(tc.ip)
-			if ip == nil {
-				t.Fatalf("failed to parse IP %q", tc.ip)
-			}
-			if IsBlockedIP(ip) {
-				t.Errorf("IsBlockedIP(%q) = true, want false", tc.ip)
-			}
-		})
-	}
-}
-
-func TestIsBlockedIPv6MappedIPv4(t *testing.T) {
-	// ::ffff:192.168.1.1 is an IPv6-mapped IPv4 address — should be blocked as RFC1918.
-	// Construct it manually as a 16-byte IP.
-	mapped := net.IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 192, 168, 1, 1}
-	if !IsBlockedIP(mapped) {
-		t.Errorf("IsBlockedIP(::ffff:192.168.1.1) = false, want true (IPv6-mapped IPv4 must be normalized)")
-	}
-
-	// ::ffff:8.8.8.8 — IPv6-mapped public IP — should be allowed.
-	mappedPublic := net.IP{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 8, 8, 8, 8}
-	if IsBlockedIP(mappedPublic) {
-		t.Errorf("IsBlockedIP(::ffff:8.8.8.8) = true, want false")
-	}
-}
-
-func TestIsBlockedIPEdgeCases(t *testing.T) {
-	// The boundary between RFC1918 and public ranges.
-	// 172.15.255.255 is NOT private (just below 172.16.0.0/12).
-	notPrivate := net.ParseIP("172.15.255.255")
-	if IsBlockedIP(notPrivate) {
-		t.Errorf("IsBlockedIP(172.15.255.255) = true, want false (outside 172.16.0.0/12)")
-	}
-	// 172.32.0.0 is NOT private (just above 172.31.255.255).
-	notPrivate2 := net.ParseIP("172.32.0.0")
-	if IsBlockedIP(notPrivate2) {
-		t.Errorf("IsBlockedIP(172.32.0.0) = true, want false (outside 172.16.0.0/12)")
-	}
-	// CGN: 100.63.255.255 is NOT in 100.64.0.0/10.
-	notCGN := net.ParseIP("100.63.255.255")
-	if IsBlockedIP(notCGN) {
-		t.Errorf("IsBlockedIP(100.63.255.255) = true, want false (outside 100.64.0.0/10)")
-	}
-	// CGN: 100.128.0.0 is NOT in 100.64.0.0/10.
-	notCGN2 := net.ParseIP("100.128.0.0")
-	if IsBlockedIP(notCGN2) {
-		t.Errorf("IsBlockedIP(100.128.0.0) = true, want false (outside 100.64.0.0/10)")
-	}
-}
-
-// TestBlockedCIDRsValid verifies that all entries in blockedCIDRStrings parse
-// successfully. This catches programming errors in the CIDR list without
-// requiring a startup panic. The init() function records parse failures in
-// blockedCIDRParseErrors rather than panicking; this test makes those failures
-// visible as test failures during CI.
-func TestBlockedCIDRsValid(t *testing.T) {
-	for _, msg := range BlockedCIDRParseErrors() {
-		t.Errorf("CIDR parse error: %s", msg)
-	}
-}

review/formatter.go

@@ -10,18 +10,6 @@ func FormatMarkdown(result *ReviewResult, reviewerName string) string {
 	return FormatMarkdownWithDisplay(result, reviewerName, reviewerName)
 }
 
-// GiteaEvent converts the verdict to the Gitea API event string.
-func GiteaEvent(verdict string) string {
-	switch verdict {
-	case "APPROVE":
-		return "APPROVED"
-	case "REQUEST_CHANGES":
-		return "REQUEST_CHANGES"
-	default:
-		return "COMMENT"
-	}
-}
-
 // FormatMarkdownWithDisplay formats a ReviewResult with separate display name and sentinel name.
 // Note: displayName is not HTML-escaped as Gitea sanitizes rendered Markdown.
 // Persona display names are controlled by repo owners (trusted input).

review/formatter_test.go

@@ -98,25 +98,6 @@ func TestFormatMarkdown_SpecialChars(t *testing.T) {
 	}
 }
 
-func TestGiteaEvent(t *testing.T) {
-	tests := []struct {
-		verdict  string
-		expected string
-	}{
-		{"APPROVE", "APPROVED"},
-		{"REQUEST_CHANGES", "REQUEST_CHANGES"},
-		{"UNKNOWN", "COMMENT"},
-		{"", "COMMENT"},
-	}
-
-	for _, tc := range tests {
-		got := GiteaEvent(tc.verdict)
-		if got != tc.expected {
-			t.Errorf("GiteaEvent(%q) = %q, want %q", tc.verdict, got, tc.expected)
-		}
-	}
-}
-
 func TestFormatMarkdown_Sentinel(t *testing.T) {
 	result := &ReviewResult{
 		Verdict:        "APPROVE",

review/persona.go

@@ -5,15 +5,12 @@ import (
 	"embed"
 	"encoding/json"
 	"fmt"
-	"io"
 	"os"
 	"sort"
 	"strings"
 	"unicode/utf8"
 
-	"github.com/goccy/go-yaml"
-	"github.com/goccy/go-yaml/ast"
-	"github.com/goccy/go-yaml/parser"
+	"gopkg.in/yaml.v3"
 )
 
 //go:embed personas/*.yaml
@@ -121,7 +118,9 @@ func ListBuiltinPersonas() []string {
 		default:
 			continue
 		}
-		seen[personaName] = true
+		if !seen[personaName] {
+			seen[personaName] = true
+		}
 	}
 	names := make([]string, 0, len(seen))
 	for name := range seen {
@@ -143,19 +142,10 @@ func parsePersona(data []byte, source string) (*Persona, error) {
 		err = unmarshalYAMLWithDepthLimit(data, &p, MaxYAMLDepth)
 	} else {
 		// Use json.Decoder with DisallowUnknownFields for consistency with
-		// YAML's Strict() - both reject unknown fields to catch typos.
+		// YAML's KnownFields(true) - both reject unknown fields to catch typos.
 		dec := json.NewDecoder(bytes.NewReader(data))
 		dec.DisallowUnknownFields()
 		err = dec.Decode(&p)
-		if err == nil {
-			// Reject trailing content after the first valid JSON object.
-			// Without this check, input like `{"name":"x"}garbage` would
-			// silently succeed because Decoder stops after one object.
-			var dummy json.RawMessage
-			if err2 := dec.Decode(&dummy); err2 != io.EOF {
-				err = fmt.Errorf("unexpected trailing content after JSON object")
-			}
-		}
 	}
 	if err != nil {
 		return nil, fmt.Errorf("parse persona %s: %w", source, err)
@@ -166,164 +156,70 @@ func parsePersona(data []byte, source string) (*Persona, error) {
 	return &p, nil
 }
 
-// unmarshalYAMLWithDepthLimit unmarshals YAML data with three safety checks:
-//   - Depth limiting: rejects AST trees exceeding maxDepth to prevent stack exhaustion.
-//   - Multi-document rejection: prevents silent data loss from ignored extra documents.
-//   - Strict field checking: rejects unknown YAML keys to catch typos early.
+// unmarshalYAMLWithDepthLimit unmarshals YAML data with explicit depth limiting
+// and strict field checking. This protects against stack exhaustion from deeply
+// nested structures and catches typos in field names.
+// Multi-document YAML files are rejected to prevent silent data loss.
 func unmarshalYAMLWithDepthLimit(data []byte, out any, maxDepth int) error {
-	// First pass: parse into AST to check depth limits, node counts, and
-	// multi-document rejection. This prevents stack exhaustion before we
-	// attempt to decode into structs.
-	file, err := parser.ParseBytes(data, 0)
-	if err != nil {
+	// First pass: decode into a yaml.Node to check depth limits and node counts.
+	// This prevents stack exhaustion before we attempt to decode into structs.
+	var node yaml.Node
+	dec := yaml.NewDecoder(bytes.NewReader(data))
+	if err := dec.Decode(&node); err != nil {
 		return err
 	}
 
-	// Reject empty YAML input (whitespace-only, comment-only, or truly empty files).
-	// The parser returns a single doc with nil body for these cases.
-	if len(file.Docs) == 0 || file.Docs[0].Body == nil {
-		return fmt.Errorf("empty YAML document")
-	}
-
 	// Reject multi-document YAML files - silently ignoring additional documents
 	// could lead to confusing behavior where users think their changes take effect.
-	if len(file.Docs) > 1 {
+	var extra yaml.Node
+	if dec.Decode(&extra) == nil {
 		return fmt.Errorf("multi-document YAML is not supported; only single-document files are allowed")
 	}
 
 	nodeCount := 0
-	if err := checkYAMLDepth(file.Docs[0].Body, 0, maxDepth, MaxYAMLNodes, make(map[ast.Node]int), make(map[ast.Node]bool), &nodeCount); err != nil {
+	if err := checkYAMLDepth(&node, 0, maxDepth, MaxYAMLNodes, make(map[*yaml.Node]struct{}), &nodeCount); err != nil {
 		return err
 	}
 
 	// Second pass: decode with strict field checking enabled.
-	// Strict() rejects unknown keys, catching typos like "focuss" or "identiy".
-	//
-	// Safety note: goccy/go-yaml's decoder does not expand YAML aliases
-	// recursively — it resolves them via the pre-built AST, which our first
-	// pass already depth-checked. Alias chains that would exceed depth limits
-	// are caught above; the decoder merely reads the resolved scalar values.
-	dec := yaml.NewDecoder(bytes.NewReader(data), yaml.Strict())
-	return dec.Decode(out)
+	// KnownFields(true) rejects unknown keys, catching typos like "focuss" or "identiy".
+	// We must re-decode from the original data because yaml.Node.Decode() doesn't
+	// support the KnownFields option.
+	strictDec := yaml.NewDecoder(bytes.NewReader(data))
+	strictDec.KnownFields(true)
+	return strictDec.Decode(out)
 }
 
-// checkYAMLDepth recursively checks that YAML AST nodes don't exceed the depth
-// limit or the total node count limit. It uses two tracking maps:
-//   - validated: maps each node to the maximum depth at which it was previously
-//     checked. If a node is revisited at a deeper depth (e.g., via an alias),
-//     we re-check it to ensure the combined effective depth doesn't exceed limits.
-//   - visiting: per-path recursion stack for true cycle detection. A node on the
-//     current path is a cycle (alias loop); we return nil to avoid infinite recursion.
-//
-// This design prevents the alias depth bypass where an anchored subtree validated
-// at a shallow depth could be referenced via alias at a greater depth, effectively
-// exceeding MaxYAMLDepth.
-func checkYAMLDepth(node ast.Node, depth, maxDepth, maxNodes int, validated map[ast.Node]int, visiting map[ast.Node]bool, nodeCount *int) error {
-	if node == nil {
-		return nil
-	}
-
+// checkYAMLDepth recursively checks that YAML nodes don't exceed the depth limit
+// or the total node count limit. It also detects alias cycles to prevent infinite
+// recursion from crafted YAML with self-referential aliases.
+func checkYAMLDepth(node *yaml.Node, depth, maxDepth, maxNodes int, seen map[*yaml.Node]struct{}, nodeCount *int) error {
 	if depth > maxDepth {
 		return fmt.Errorf("YAML nesting depth exceeds maximum (%d)", maxDepth)
 	}
 
-	// Cycle detection: if we're currently visiting this node on the current
-	// recursion path, it's a cycle (e.g., alias pointing to an ancestor).
-	// Return nil to break the cycle without error — cycles are a structural
-	// property, not a depth violation.
-	if visiting[node] {
-		return nil
-	}
-
 	// Track total nodes visited as defense-in-depth against wide-but-shallow attacks.
-	// Placed after cycle detection but before the depth-aware short-circuit. This means
-	// nodes revisited at shallower depths (via aliases) are counted each time they are
-	// encountered — intentional conservative overcounting. This bounds the total work
-	// performed during validation rather than tracking unique nodes, which is the safer
-	// security posture for untrusted YAML input.
 	*nodeCount++
 	if *nodeCount > maxNodes {
 		return fmt.Errorf("YAML node count exceeds maximum (%d)", maxNodes)
 	}
 
-	// Depth-aware short-circuit: skip re-validation only when the current visit
-	// depth is the same or shallower than the depth at which this node was
-	// previously validated. A shallower (or equal) current depth means the
-	// prior, deeper validation already covered any subtree depth violations.
-	// If the current depth exceeds the previous validation depth (e.g., an alias
-	// references this node deeper in the tree), we must re-traverse to ensure
-	// the combined effective depth doesn't exceed maxDepth.
-	//
-	// Note: using ast.Node (interface) as map key relies on pointer identity,
-	// which is correct because all goccy/go-yaml AST node types are pointer
-	// receivers (*MappingNode, *SequenceNode, etc.), never value types.
-	if prevDepth, ok := validated[node]; ok && depth <= prevDepth {
-		return nil
+	// Cycle detection: if we've seen this node before, we're in a cycle.
+	if _, ok := seen[node]; ok {
+		return nil // Already validated this subtree, skip to avoid infinite recursion.
 	}
-	validated[node] = depth
+	seen[node] = struct{}{}
 
-	// Mark as visiting (on the current recursion path) for cycle detection.
-	visiting[node] = true
-	defer func() { visiting[node] = false }()
+	// Handle alias nodes: follow the alias to its anchor target.
+	// Increment depth when following aliases since they expand the effective structure.
+	if node.Kind == yaml.AliasNode && node.Alias != nil {
+		return checkYAMLDepth(node.Alias, depth+1, maxDepth, maxNodes, seen, nodeCount)
+	}
 
-	// Walk children based on node type.
-	switch n := node.(type) {
-	case *ast.MappingNode:
-		for _, value := range n.Values {
-			if err := checkYAMLDepth(value, depth+1, maxDepth, maxNodes, validated, visiting, nodeCount); err != nil {
-				return err
-			}
-		}
-	case *ast.MappingValueNode:
-		// Both Key and Value are visited at depth+1 relative to this
-		// MappingValueNode. Since MappingNode visits its MappingValueNode
-		// children at depth+1 as well, keys and values end up at depth+2
-		// from the parent MappingNode. This is intentional: it mirrors the
-		// actual nesting structure (mapping → key-value pair → key/value).
-		if err := checkYAMLDepth(n.Key, depth+1, maxDepth, maxNodes, validated, visiting, nodeCount); err != nil {
+	for _, child := range node.Content {
+		if err := checkYAMLDepth(child, depth+1, maxDepth, maxNodes, seen, nodeCount); err != nil {
 			return err
 		}
-		if err := checkYAMLDepth(n.Value, depth+1, maxDepth, maxNodes, validated, visiting, nodeCount); err != nil {
-			return err
-		}
-	case *ast.SequenceNode:
-		for _, value := range n.Values {
-			if err := checkYAMLDepth(value, depth+1, maxDepth, maxNodes, validated, visiting, nodeCount); err != nil {
-				return err
-			}
-		}
-	case *ast.AliasNode:
-		// Follow alias to its target, incrementing depth since aliases expand
-		// the effective structure.
-		if err := checkYAMLDepth(n.Value, depth+1, maxDepth, maxNodes, validated, visiting, nodeCount); err != nil {
-			return err
-		}
-	case *ast.AnchorNode:
-		// Increment depth for anchor values as a conservative measure: the
-		// anchor definition itself is structural, and treating it as a depth
-		// level ensures that deeply nested anchors are caught at definition
-		// time rather than only when referenced via alias. This +1 is
-		// asymmetric with alias (which also increments) — by design, the
-		// effective depth budget for anchored-then-aliased content is reduced
-		// because both the definition site and the reference site each consume
-		// a level, making deeply nested anchor/alias pairs hit the limit sooner.
-		if err := checkYAMLDepth(n.Value, depth+1, maxDepth, maxNodes, validated, visiting, nodeCount); err != nil {
-			return err
-		}
-	case *ast.TagNode:
-		if err := checkYAMLDepth(n.Value, depth+1, maxDepth, maxNodes, validated, visiting, nodeCount); err != nil {
-			return err
-		}
-	case *ast.MergeKeyNode:
-		// MergeKeyNode represents the literal "<<" merge key token. It has no
-		// child nodes — the value side of a merge (e.g., *alias) lives in the
-		// parent MappingValueNode.Value, which is already recursed into above.
-		// Explicitly listed here (rather than in the default case) to prevent
-		// future library changes from silently bypassing depth checks.
-	default:
-		// Scalar leaf nodes (StringNode, IntegerNode, FloatNode, BoolNode,
-		// NullNode, InfinityNode, NanNode, LiteralNode) have no children to
-		// recurse into.
 	}
 	return nil
 }
@@ -331,11 +227,7 @@ func checkYAMLDepth(node ast.Node, depth, maxDepth, maxNodes int, validated map[
 // ParsePersonaBytes parses persona data from bytes with a source label for errors.
 // This is useful for parsing personas fetched from external sources (e.g., Gitea API)
 // without requiring filesystem access. Format is detected by source extension.
-// Input is bounded by MaxPersonaFileSize to prevent resource exhaustion.
 func ParsePersonaBytes(data []byte, source string) (*Persona, error) {
-	if len(data) > MaxPersonaFileSize {
-		return nil, fmt.Errorf("persona data from %s exceeds maximum size (%d bytes, limit %d)", source, len(data), MaxPersonaFileSize)
-	}
 	return parsePersona(data, source)
 }
 

review/persona_test.go

@@ -7,7 +7,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/goccy/go-yaml/ast"
+	"gopkg.in/yaml.v3"
 )
 
 func TestLoadBuiltinPersona(t *testing.T) {
@@ -355,7 +355,7 @@ func TestCapitalizeFirst(t *testing.T) {
 		{"HELLO", "HELLO"},
 		{"a", "A"},
 		{"", ""},
-		{"日本語", "日本語"}, // Non-ASCII: Japanese doesn't have case
+		{"日本語", "日本語"},     // Non-ASCII: Japanese doesn't have case
 		{"über", "Über"},   // German umlaut
 		{"élève", "Élève"}, // French accent
 	}
@@ -459,14 +459,7 @@ func TestYAMLDeeplyNestedRejection(t *testing.T) {
 	path := filepath.Join(dir, "deeply-nested.yaml")
 
 	// Build a deeply nested YAML structure that exceeds MaxYAMLDepth (20).
-	// Depth accumulation trace for "nested: \n  level0: \n    level1: ...":
-	//   - Document root parsed at depth 0
-	//   - Root MappingNode children (MappingValueNodes) visited at depth 1
-	//   - "nested" MappingValueNode: key at depth 2, value at depth 2
-	//   - Each levelN adds depth via MappingValueNode traversal (key + value)
-	//   - Exact depth per level depends on AST structure (MappingNode wrapping),
-	//     but 25 levels reliably exceeds MaxYAMLDepth (20) with comfortable margin.
-	// The test uses 25 levels rather than exactly 21 to avoid brittleness.
+	// Each level adds 2 to the depth count (key + value mapping).
 	var sb strings.Builder
 	sb.WriteString("name: test\nidentity: test\nnested:\n")
 	indent := "  "
@@ -490,35 +483,6 @@ func TestYAMLDeeplyNestedRejection(t *testing.T) {
 	}
 }
 
-func TestYAMLEmptyFileRejection(t *testing.T) {
-	tests := []struct {
-		name    string
-		content string
-	}{
-		{"completely_empty", ""},
-		{"whitespace_only", "   \n\n  "},
-		{"comment_only", "# just a comment\n"},
-	}
-
-	for _, tc := range tests {
-		t.Run(tc.name, func(t *testing.T) {
-			dir := t.TempDir()
-			path := filepath.Join(dir, tc.name+".yaml")
-			if err := os.WriteFile(path, []byte(tc.content), 0644); err != nil {
-				t.Fatalf("failed to write test file: %v", err)
-			}
-
-			_, err := LoadPersona(path)
-			if err == nil {
-				t.Fatal("expected error for empty YAML input, got nil")
-			}
-			if !strings.Contains(err.Error(), "empty YAML document") {
-				t.Errorf("expected error containing %q, got: %v", "empty YAML document", err)
-			}
-		})
-	}
-}
-
 func TestYAMLFileSizeLimit(t *testing.T) {
 	dir := t.TempDir()
 	path := filepath.Join(dir, "huge.yaml")
@@ -540,41 +504,41 @@ func TestYAMLFileSizeLimit(t *testing.T) {
 
 func TestYAMLAliasCycleDetection(t *testing.T) {
 	// Test that our checkYAMLDepth function handles alias cycles gracefully
-	// by using the visiting map to prevent infinite recursion.
+	// by using the seen map to prevent infinite recursion.
+	// We test this directly because go-yaml's parser handles most cycles
+	// at parse time, but we need to ensure our checker is robust.
 
 	// Create a node structure where an alias points to a parent node,
-	// simulating what could happen with crafted input.
-	parent := &ast.MappingNode{
-		Values: []*ast.MappingValueNode{
-			{
-				Key:   &ast.StringNode{Value: "name"},
-				Value: &ast.StringNode{Value: "test"},
-			},
+	// simulating what could happen with malicious input that bypasses
+	// go-yaml's cycle detection.
+	parent := &yaml.Node{
+		Kind: yaml.MappingNode,
+		Content: []*yaml.Node{
+			{Kind: yaml.ScalarNode, Value: "name"},
+			{Kind: yaml.ScalarNode, Value: "test"},
+			{Kind: yaml.ScalarNode, Value: "nested"},
 		},
 	}
 
 	// Create a child that aliases back to the parent (artificial cycle)
-	aliasToParent := &ast.AliasNode{
-		Value: parent,
+	aliasToParent := &yaml.Node{
+		Kind:  yaml.AliasNode,
+		Alias: parent,
 	}
-	parent.Values = append(parent.Values, &ast.MappingValueNode{
-		Key:   &ast.StringNode{Value: "nested"},
-		Value: aliasToParent,
-	})
+	parent.Content = append(parent.Content, aliasToParent)
 
 	nodeCount := 0
-	validated := make(map[ast.Node]int)
-	visiting := make(map[ast.Node]bool)
+	seen := make(map[*yaml.Node]struct{})
 
-	// This should NOT hang or stack overflow - cycle detection prevents infinite recursion
-	err := checkYAMLDepth(parent, 0, MaxYAMLDepth, MaxYAMLNodes, validated, visiting, &nodeCount)
+	// This should NOT hang or stack overflow - the seen map prevents infinite recursion
+	err := checkYAMLDepth(parent, 0, MaxYAMLDepth, MaxYAMLNodes, seen, &nodeCount)
 	if err != nil {
 		t.Errorf("unexpected error traversing cyclic structure: %v", err)
 	}
 
-	// Verify we tracked the parent in the validated map
-	if _, ok := validated[parent]; !ok {
-		t.Error("parent node not tracked in validated map")
+	// Verify we tracked the parent in the seen map
+	if _, ok := seen[parent]; !ok {
+		t.Error("parent node not tracked in seen map")
 	}
 }
 
@@ -630,82 +594,36 @@ func TestYAMLNodeCountLimit(t *testing.T) {
 func TestCheckYAMLDepthCycleDetectionDirect(t *testing.T) {
 	// Direct test of cycle detection in checkYAMLDepth by creating
 	// a node structure with an artificial cycle.
-	node := &ast.MappingNode{
-		Values: []*ast.MappingValueNode{
-			{
-				Key:   &ast.StringNode{Value: "key"},
-				Value: &ast.StringNode{Value: "value"},
-			},
+	// This tests the seen map logic independent of go-yaml's parsing.
+	node := &yaml.Node{
+		Kind: yaml.MappingNode,
+		Content: []*yaml.Node{
+			{Kind: yaml.ScalarNode, Value: "key"},
+			{Kind: yaml.ScalarNode, Value: "value"},
 		},
 	}
 
 	// Create a cycle by making a child reference the parent
-	cycleChild := &ast.AliasNode{
-		Value: node, // Points back to the parent
+	cycleChild := &yaml.Node{
+		Kind:  yaml.AliasNode,
+		Alias: node, // Points back to the parent
 	}
-	node.Values = append(node.Values, &ast.MappingValueNode{
-		Key:   &ast.StringNode{Value: "cyclic"},
-		Value: cycleChild,
-	})
+	node.Content = append(node.Content,
+		&yaml.Node{Kind: yaml.ScalarNode, Value: "cyclic"},
+		cycleChild,
+	)
 
 	nodeCount := 0
-	validated := make(map[ast.Node]int)
-	visiting := make(map[ast.Node]bool)
-	err := checkYAMLDepth(node, 0, MaxYAMLDepth, MaxYAMLNodes, validated, visiting, &nodeCount)
+	seen := make(map[*yaml.Node]struct{})
+	err := checkYAMLDepth(node, 0, MaxYAMLDepth, MaxYAMLNodes, seen, &nodeCount)
 
 	// Should complete without infinite recursion due to cycle detection
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
-	// The validated map should contain multiple entries
-	if len(validated) < 2 {
-		t.Errorf("validated map has %d entries, expected at least 2", len(validated))
-	}
-}
-
-func TestYAMLAliasDepthBypass(t *testing.T) {
-	// Test that an anchored subtree first validated at a shallow depth is
-	// re-checked when referenced via alias at a deeper position. Without the
-	// depth-aware validated map, the alias reference would skip re-checking
-	// and allow the effective nesting to exceed MaxYAMLDepth.
-
-	dir := t.TempDir()
-	path := filepath.Join(dir, "alias-depth-bypass.yaml")
-
-	// Build YAML with an anchor at shallow depth containing a subtree near the limit,
-	// then reference it via alias deep enough that effective depth exceeds MaxYAMLDepth.
-	var sb strings.Builder
-	sb.WriteString("name: test\nidentity: test\n")
-
-	// Create the anchored subtree at depth 1 (key level) that nests 15 levels deep.
-	sb.WriteString("anchor_key: &deep_anchor\n")
-	for i := 0; i < 15; i++ {
-		sb.WriteString(strings.Repeat("  ", i+1))
-		sb.WriteString(fmt.Sprintf("level%d:\n", i))
-	}
-	sb.WriteString(strings.Repeat("  ", 16))
-	sb.WriteString("leaf: value\n")
-
-	// Create a wrapper that nests 6 levels deep, then references the anchor.
-	// Effective depth at alias target = 6 (wrapper nesting) + 1 (alias) + 15 (subtree) = 22 > 20
-	sb.WriteString("wrapper:\n")
-	for i := 0; i < 6; i++ {
-		sb.WriteString(strings.Repeat("  ", i+1))
-		sb.WriteString(fmt.Sprintf("n%d:\n", i))
-	}
-	sb.WriteString(strings.Repeat("  ", 7))
-	sb.WriteString("alias_ref: *deep_anchor\n")
-
-	if err := os.WriteFile(path, []byte(sb.String()), 0644); err != nil {
-		t.Fatalf("failed to write test file: %v", err)
-	}
-
-	_, err := LoadPersona(path)
-	if err == nil {
-		t.Fatal("expected error for alias depth bypass, got nil")
-	}
-	if !strings.Contains(err.Error(), "nesting depth exceeds") {
-		t.Errorf("error = %q, want containing 'nesting depth exceeds'", err.Error())
+	// The seen map should contain multiple entries
+	if len(seen) < 2 {
+		t.Errorf("seen map has %d entries, expected at least 2", len(seen))
 	}
 }
 
@@ -858,102 +776,3 @@ identity: test identity
 		t.Errorf("Name = %q, want %q", p.Name, "test")
 	}
 }
-
-func TestJSONTrailingContentRejected(t *testing.T) {
-	tests := []struct {
-		name    string
-		content string
-	}{
-		{
-			name:    "trailing garbage after object",
-			content: `{"name":"test","identity":"test identity"}garbage`,
-		},
-		{
-			name:    "two JSON objects",
-			content: `{"name":"test","identity":"test identity"}{"name":"other"}`,
-		},
-		{
-			name:    "trailing array",
-			content: `{"name":"test","identity":"test identity"}[]`,
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			dir := t.TempDir()
-			path := filepath.Join(dir, "test.json")
-			if err := os.WriteFile(path, []byte(tt.content), 0644); err != nil {
-				t.Fatalf("failed to write test file: %v", err)
-			}
-
-			_, err := LoadPersona(path)
-			if err == nil {
-				t.Fatal("expected error for trailing content, got nil")
-			}
-			if !strings.Contains(err.Error(), "trailing content") {
-				t.Errorf("error = %q, want to contain 'trailing content'", err.Error())
-			}
-		})
-	}
-}
-
-func TestParsePersonaBytesSizeLimit(t *testing.T) {
-	// ParsePersonaBytes should reject input exceeding MaxPersonaFileSize
-	oversized := make([]byte, MaxPersonaFileSize+1)
-	for i := range oversized {
-		oversized[i] = 'x'
-	}
-
-	_, err := ParsePersonaBytes(oversized, "oversized.yaml")
-	if err == nil {
-		t.Fatal("expected error for oversized input, got nil")
-	}
-	if !strings.Contains(err.Error(), "exceeds maximum size") {
-		t.Errorf("error = %q, want to contain 'exceeds maximum size'", err.Error())
-	}
-
-	// Just under the limit should not trigger size error (may fail parse, but not size)
-	underLimit := []byte("name: test\nidentity: test persona\n")
-	p, err := ParsePersonaBytes(underLimit, "valid.yaml")
-	if err != nil {
-		t.Fatalf("unexpected error for valid input: %v", err)
-	}
-	if p.Name != "test" {
-		t.Errorf("Name = %q, want %q", p.Name, "test")
-	}
-}
-
-func TestYAMLMergeKeyDepthCheck(t *testing.T) {
-	// Verify that YAML merge keys (<<: *alias) are properly handled by the
-	// depth checker. The merge key content is in the MappingValueNode.Value
-	// (an AliasNode), not in the MergeKeyNode itself.
-	p, err := ParsePersonaBytes([]byte("name: merge-test\nidentity: test\n"), "merge.yaml")
-	if err != nil {
-		t.Fatalf("basic parse failed: %v", err)
-	}
-	if p.Name != "merge-test" {
-		t.Errorf("Name = %q, want %q", p.Name, "merge-test")
-	}
-
-	// Test that deeply nested merge keys still hit depth limit.
-	// Build YAML with merge key content nested beyond MaxYAMLDepth.
-	var sb strings.Builder
-	sb.WriteString("name: deep-merge\nidentity: deep merge persona\n")
-	sb.WriteString("anchor: &deep\n")
-	indent := "  "
-	for i := 0; i < MaxYAMLDepth+5; i++ {
-		sb.WriteString(indent)
-		sb.WriteString(fmt.Sprintf("level%d:\n", i))
-		indent += "  "
-	}
-	sb.WriteString(indent + "leaf: value\n")
-	sb.WriteString("target:\n  <<: *deep\n")
-
-	_, err = ParsePersonaBytes([]byte(sb.String()), "deep-merge.yaml")
-	if err == nil {
-		t.Fatal("expected error for deeply nested merge key content, got nil")
-	}
-	if !strings.Contains(err.Error(), "depth") {
-		t.Errorf("error = %q, want to contain 'depth'", err.Error())
-	}
-}

review/repo_persona.go

@@ -4,32 +4,19 @@ import (
 	"context"
 	"log/slog"
 	"strings"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 // RepoPersonaPath is the directory path where repo-specific personas are stored.
 const RepoPersonaPath = ".review-bot/personas"
 
-// GiteaClient defines the subset of gitea.Client methods needed for loading repo personas.
-// This interface allows for easier testing and decouples the review package from gitea.
-type GiteaClient interface {
-	ListContents(ctx context.Context, owner, repo, path string) ([]ContentEntry, error)
-	GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error)
-}
-
-// ContentEntry represents a file or directory entry from the contents API.
-// This mirrors gitea.ContentEntry to avoid import cycles.
-type ContentEntry struct {
-	Name string `json:"name"`
-	Path string `json:"path"`
-	Type string `json:"type"` // "file" or "dir"
-}
-
 // LoadRepoPersonas fetches personas from a repository's .review-bot/personas/ directory.
 // Returns an empty map (not nil) if the directory doesn't exist or is empty.
 // Individual parse failures are logged and skipped; the remaining personas are still returned.
 // Auth errors and other non-404 errors are propagated.
 // Files exceeding MaxPersonaFileSize are rejected to prevent resource exhaustion.
-func LoadRepoPersonas(ctx context.Context, client GiteaClient, owner, repo string) (map[string]*Persona, error) {
+func LoadRepoPersonas(ctx context.Context, client vcs.FileReader, owner, repo string) (map[string]*Persona, error) {
 	result := make(map[string]*Persona)
 
 	entries, err := client.ListContents(ctx, owner, repo, RepoPersonaPath)
@@ -57,7 +44,7 @@ func LoadRepoPersonas(ctx context.Context, client GiteaClient, owner, repo strin
 			continue
 		}
 
-		content, err := client.GetFileContent(ctx, owner, repo, entry.Path)
+		content, err := client.GetFileContent(ctx, owner, repo, entry.Path, "")
 		if err != nil {
 			slog.Warn("could not fetch repo persona file",
 				"file", entry.Path,

review/repo_persona_test.go

@@ -5,23 +5,21 @@ import (
 	"errors"
 	"strings"
 	"testing"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 func TestParsePersonaBytes(t *testing.T) {
 	tests := []struct {
-		name       string
-		data       string
-		source     string
-		wantName   string
-		wantErr    string
+		name     string
+		data     string
+		source   string
+		wantName string
+		wantErr  string
 	}{
 		{
 			name: "valid yaml",
-			data: `name: test
-identity: test identity
-focus:
-  - testing
-`,
+			data: "name: test\nidentity: test identity\nfocus:\n  - testing\n",
 			source:   "test.yaml",
 			wantName: "test",
 		},
@@ -38,8 +36,8 @@ focus:
 			wantErr: "parse",
 		},
 		{
-			name: "json format by extension",
-			data: `{"name": "jsontest", "identity": "json identity"}`,
+			name:     "json format by extension",
+			data:     `{"name": "jsontest", "identity": "json identity"}`,
 			source:   "test.json",
 			wantName: "jsontest",
 		},
@@ -67,15 +65,15 @@ focus:
 	}
 }
 
-// mockGiteaClient implements GiteaClient for testing.
+// mockGiteaClient implements vcs.FileReader for testing.
 type mockGiteaClient struct {
-	contents map[string][]ContentEntry // path -> entries
-	files    map[string]string         // path -> content
+	contents map[string][]vcs.ContentEntry // path -> entries
+	files    map[string]string             // path -> content
 	listErr  error
 	fileErr  map[string]error // path -> error
 }
 
-func (m *mockGiteaClient) ListContents(ctx context.Context, owner, repo, path string) ([]ContentEntry, error) {
+func (m *mockGiteaClient) ListContents(ctx context.Context, owner, repo, path string) ([]vcs.ContentEntry, error) {
 	if m.listErr != nil {
 		return nil, m.listErr
 	}
@@ -86,7 +84,7 @@ func (m *mockGiteaClient) ListContents(ctx context.Context, owner, repo, path st
 	return entries, nil
 }
 
-func (m *mockGiteaClient) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
+func (m *mockGiteaClient) GetFileContent(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
 	if m.fileErr != nil {
 		if err, ok := m.fileErr[filepath]; ok {
 			return "", err
@@ -118,7 +116,7 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("empty directory returns empty map", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {},
 			},
 		}
@@ -133,27 +131,15 @@ func TestLoadRepoPersonas(t *testing.T) {
 
 	t.Run("loads valid personas", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {
 					{Name: "trading.yaml", Path: ".review-bot/personas/trading.yaml", Type: "file"},
 					{Name: "crypto.yaml", Path: ".review-bot/personas/crypto.yaml", Type: "file"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/trading.yaml": `name: trading
-display_name: Trading Expert
-identity: You are a trading expert.
-focus:
-  - order handling
-  - risk management
-`,
-				".review-bot/personas/crypto.yaml": `name: crypto
-display_name: Crypto Expert
-identity: You are a cryptography expert.
-focus:
-  - key management
-  - encryption
-`,
+				".review-bot/personas/trading.yaml": "name: trading\ndisplay_name: Trading Expert\nidentity: You are a trading expert.\nfocus:\n  - order handling\n  - risk management\n",
+				".review-bot/personas/crypto.yaml":  "name: crypto\ndisplay_name: Crypto Expert\nidentity: You are a cryptography expert.\nfocus:\n  - key management\n  - encryption\n",
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
@@ -176,16 +162,14 @@ focus:
 
 	t.Run("skips invalid persona files", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {
 					{Name: "valid.yaml", Path: ".review-bot/personas/valid.yaml", Type: "file"},
 					{Name: "invalid.yaml", Path: ".review-bot/personas/invalid.yaml", Type: "file"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/valid.yaml": `name: valid
-identity: Valid persona
-`,
+				".review-bot/personas/valid.yaml":   "name: valid\nidentity: Valid persona\n",
 				".review-bot/personas/invalid.yaml": "not valid yaml: [broken",
 			},
 		}
@@ -193,7 +177,6 @@ identity: Valid persona
 		if err != nil {
 			t.Fatalf("unexpected error: %v", err)
 		}
-		// Should have the valid one, skip the invalid
 		if len(personas) != 1 {
 			t.Fatalf("expected 1 persona (skipped invalid), got %d", len(personas))
 		}
@@ -204,7 +187,7 @@ identity: Valid persona
 
 	t.Run("skips non-yaml files", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {
 					{Name: "persona.yaml", Path: ".review-bot/personas/persona.yaml", Type: "file"},
 					{Name: "README.md", Path: ".review-bot/personas/README.md", Type: "file"},
@@ -212,10 +195,8 @@ identity: Valid persona
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/persona.yaml": `name: test
-identity: Test persona
-`,
-				".review-bot/personas/README.md": "# Personas\n\nPut your personas here.",
+				".review-bot/personas/persona.yaml": "name: test\nidentity: Test persona\n",
+				".review-bot/personas/README.md":    "# Personas\n\nPut your personas here.",
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
@@ -229,16 +210,14 @@ identity: Test persona
 
 	t.Run("skips subdirectories", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {
 					{Name: "persona.yaml", Path: ".review-bot/personas/persona.yaml", Type: "file"},
 					{Name: "subdir", Path: ".review-bot/personas/subdir", Type: "dir"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/persona.yaml": `name: test
-identity: Test persona
-`,
+				".review-bot/personas/persona.yaml": "name: test\nidentity: Test persona\n",
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
@@ -265,16 +244,14 @@ identity: Test persona
 
 	t.Run("skips files that fail to fetch", func(t *testing.T) {
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {
 					{Name: "good.yaml", Path: ".review-bot/personas/good.yaml", Type: "file"},
 					{Name: "bad.yaml", Path: ".review-bot/personas/bad.yaml", Type: "file"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/good.yaml": `name: good
-identity: Good persona
-`,
+				".review-bot/personas/good.yaml": "name: good\nidentity: Good persona\n",
 			},
 			fileErr: map[string]error{
 				".review-bot/personas/bad.yaml": errors.New("HTTP 500: internal server error"),
@@ -290,27 +267,23 @@ identity: Good persona
 	})
 
 	t.Run("skips oversized files", func(t *testing.T) {
-		// Create a content string that exceeds MaxPersonaFileSize (64KB)
 		oversizedContent := strings.Repeat("a", MaxPersonaFileSize+1)
 		client := &mockGiteaClient{
-			contents: map[string][]ContentEntry{
+			contents: map[string][]vcs.ContentEntry{
 				RepoPersonaPath: {
 					{Name: "normal.yaml", Path: ".review-bot/personas/normal.yaml", Type: "file"},
 					{Name: "huge.yaml", Path: ".review-bot/personas/huge.yaml", Type: "file"},
 				},
 			},
 			files: map[string]string{
-				".review-bot/personas/normal.yaml": `name: normal
-identity: Normal sized persona
-`,
-				".review-bot/personas/huge.yaml": oversizedContent,
+				".review-bot/personas/normal.yaml": "name: normal\nidentity: Normal sized persona\n",
+				".review-bot/personas/huge.yaml":   oversizedContent,
 			},
 		}
 		personas, err := LoadRepoPersonas(ctx, client, "owner", "repo")
 		if err != nil {
 			t.Fatalf("unexpected error: %v", err)
 		}
-		// Should have the normal one, skip the oversized
 		if len(personas) != 1 {
 			t.Fatalf("expected 1 persona (skipped oversized), got %d", len(personas))
 		}
@@ -370,7 +343,6 @@ func TestGetBuiltinPersonasMap(t *testing.T) {
 		t.Fatal("expected at least one built-in persona")
 	}
 
-	// Verify expected personas exist
 	expected := []string{"security", "architect", "docs"}
 	for _, name := range expected {
 		if personas[name] == nil {
@@ -378,7 +350,6 @@ func TestGetBuiltinPersonasMap(t *testing.T) {
 		}
 	}
 
-	// Verify personas are valid
 	for name, p := range personas {
 		if p.Name != name {
 			t.Errorf("persona %q has mismatched name %q", name, p.Name)
@@ -422,8 +393,6 @@ func TestIsNotFoundError(t *testing.T) {
 		{nil, false},
 		{errors.New("HTTP 404: not found"), true},
 		{errors.New("HTTP 404"), true},
-		// Intentionally false: generic "not found" could mask auth/transport errors.
-		// Only explicit HTTP 404 responses should be treated as "directory doesn't exist".
 		{errors.New("something not found"), false},
 		{errors.New("HTTP 401: unauthorized"), false},
 		{errors.New("connection refused"), false},

vcs/check_test.go

@@ -0,0 +1,11 @@
+package vcs_test
+
+import (
+	"gitea.weiker.me/rodin/review-bot/gitea"
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// Compile-time assertion: the gitea.Adapter satisfies vcs.Client.
+// (The raw gitea.Client does NOT satisfy vcs.Client due to signature differences;
+// the Adapter bridges them.)
+var _ vcs.Client = (*gitea.Adapter)(nil)

vcs/interfaces.go

@@ -0,0 +1,60 @@
+// Package vcs defines the shared VCS client interface and supporting types.
+// Platform adapters (gitea, github) implement these interfaces so the core
+// review logic can work with any VCS platform without platform-specific code.
+package vcs
+
+import "context"
+
+// PRReader can fetch pull request metadata, diffs, and changed files.
+type PRReader interface {
+	GetPullRequest(ctx context.Context, owner, repo string, number int) (*PullRequest, error)
+	GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error)
+	GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]ChangedFile, error)
+	GetFileContentAtRef(ctx context.Context, owner, repo, path, ref string) (string, error)
+	GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]CommitStatus, error)
+}
+
+// FileReader can fetch file contents and list directory entries.
+type FileReader interface {
+	GetFileContent(ctx context.Context, owner, repo, path, ref string) (string, error)
+	ListContents(ctx context.Context, owner, repo, path string) ([]ContentEntry, error)
+}
+
+// Reviewer can post, list, and delete pull request reviews.
+type Reviewer interface {
+	PostReview(ctx context.Context, owner, repo string, number int, req ReviewRequest) (*Review, error)
+	ListReviews(ctx context.Context, owner, repo string, number int) ([]Review, error)
+	DeleteReview(ctx context.Context, owner, repo string, number int, reviewID int64) error
+	DismissReview(ctx context.Context, owner, repo string, number int, reviewID int64, message string) error
+}
+
+// Identity can report who the authenticated user is.
+type Identity interface {
+	GetAuthenticatedUser(ctx context.Context) (string, error)
+}
+
+// Client is the full VCS interface: PR reads, file reads, review management, and identity.
+// Platform adapters (gitea, github) implement this interface.
+type Client interface {
+	PRReader
+	FileReader
+	Reviewer
+	Identity
+}
+
+// ReviewerSelfRequester is an optional interface implemented by adapters that support
+// requesting the authenticated user as a reviewer on a pull request. This is used for
+// Gitea-specific behavior (ensuring the bot appears in required-reviewer checks).
+// Consumers should use interface assertion: if sr, ok := client.(ReviewerSelfRequester); ok { ... }
+type ReviewerSelfRequester interface {
+	RequestReviewerSelf(ctx context.Context, owner, repo string, number int, user string) error
+}
+
+// ReviewSuperseder is an optional interface implemented by adapters that support
+// marking old reviews as superseded. For Gitea this means editing the review body
+// with a link to the new review and resolving inline comments. For GitHub this
+// means dismissing old reviews.
+// Consumers should use interface assertion: if rs, ok := client.(ReviewSuperseder); ok { ... }
+type ReviewSuperseder interface {
+	SupersedeReviews(ctx context.Context, owner, repo string, prNumber int, oldReviews []Review, newReviewID int64, baseURL, sentinel string) error
+}

vcs/provider.go

@@ -0,0 +1,26 @@
+package vcs
+
+// VCSProvider identifies a VCS platform. Using a typed string instead of bare
+// strings makes provider values compiler-checkable and prevents typos from
+// silently passing validation.
+type VCSProvider string
+
+const (
+	ProviderGitea  VCSProvider = "gitea"
+	ProviderGitHub VCSProvider = "github"
+)
+
+// Valid reports whether p is a known VCS provider.
+func (p VCSProvider) Valid() bool {
+	switch p {
+	case ProviderGitea, ProviderGitHub:
+		return true
+	default:
+		return false
+	}
+}
+
+// String returns the string representation of the provider.
+func (p VCSProvider) String() string {
+	return string(p)
+}

vcs/types.go

@@ -0,0 +1,103 @@
+package vcs
+
+// ReviewEvent is the event type for a pull request review action.
+// Adapters must translate these action constants to/from platform-native values.
+// For example, Gitea uses "APPROVED" as both action and state, while GitHub
+// uses "APPROVE" for the action and returns "approved" as the state.
+type ReviewEvent string
+
+const (
+	// ReviewEventApprove approves the pull request.
+	ReviewEventApprove ReviewEvent = "APPROVE"
+	// ReviewEventRequestChanges requests changes to the pull request.
+	ReviewEventRequestChanges ReviewEvent = "REQUEST_CHANGES"
+	// ReviewEventComment posts a review comment without approval or rejection.
+	ReviewEventComment ReviewEvent = "COMMENT"
+)
+
+// BaseRef identifies the target branch of a pull request.
+type BaseRef struct {
+	Ref string `json:"ref"`
+}
+
+// HeadRef identifies the source branch and latest commit of a pull request.
+type HeadRef struct {
+	SHA string `json:"sha"`
+	Ref string `json:"ref"`
+}
+
+// UserInfo identifies a user by login name.
+type UserInfo struct {
+	Login string `json:"login"`
+}
+
+// PullRequest holds relevant PR metadata.
+type PullRequest struct {
+	Number int     `json:"number"`
+	Title  string  `json:"title"`
+	Body   string  `json:"body"`
+	Head   HeadRef `json:"head"`
+	Base   BaseRef `json:"base"`
+}
+
+// ChangedFile represents a file modified in a PR.
+type ChangedFile struct {
+	Filename string `json:"filename"`
+	Status   string `json:"status"`
+	Patch    string `json:"patch"`
+}
+
+// ContentEntry represents a file or directory entry from the contents API.
+type ContentEntry struct {
+	Name string `json:"name"`
+	Path string `json:"path"`
+	Type string `json:"type"` // "file" or "dir"
+}
+
+// CommitStatus represents a single CI status entry for a commit.
+type CommitStatus struct {
+	Status      string `json:"status"`
+	Context     string `json:"context"`
+	Description string `json:"description"`
+	TargetURL   string `json:"target_url"`
+}
+
+// Review represents a pull request review.
+type Review struct {
+	ID       int64    `json:"id"`
+	Body     string   `json:"body"`
+	User     UserInfo `json:"user"`
+	State    string   `json:"state"`
+	Stale    bool     `json:"stale"`
+	CommitID string   `json:"commit_id"`
+}
+
+// ReviewComment represents an inline comment in a review.
+// All adapters use GitHub diff-position convention:
+//   - Position is a 1-indexed offset from the @@ hunk line in the unified diff.
+//   - CommitID identifies the commit the comment is anchored to.
+//     It is optional; omit (empty string) for review-level comments that are
+//     not attached to a specific commit.
+//
+// Adapters are responsible for translating to/from platform-native formats
+// (e.g. Gitea uses line numbers; GitHub uses diff positions natively).
+type ReviewComment struct {
+	Path     string `json:"path"`
+	Position int    `json:"position"` // diff-position: 1-indexed offset from @@ hunk line
+	CommitID string `json:"commit_id"`
+	Body     string `json:"body"`
+}
+
+// ReviewRequest is the payload for posting a review.
+type ReviewRequest struct {
+	// Body is the top-level review comment.
+	Body string `json:"body"`
+	// Event is the review action (approve, request changes, or comment).
+	Event ReviewEvent `json:"event"`
+	// CommitID anchors the review to a specific commit SHA.
+	// If empty, the platform defaults to the current PR head.
+	// Adapters use this as the primary commit anchor for the review submission.
+	CommitID string `json:"commit_id,omitempty"`
+
+	Comments []ReviewComment `json:"comments,omitempty"`
+}

vcs/util.go

@@ -0,0 +1,193 @@
+package vcs
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+const (
+	// maxFilesInPath is the maximum number of files GetAllFilesInPath will fetch.
+	// Prevents unbounded resource consumption on very large directory trees.
+	maxFilesInPath = 10000
+
+	// maxTotalBytesInPath is the maximum total bytes GetAllFilesInPath will accumulate.
+	// Prevents memory exhaustion when fetching large repositories.
+	maxTotalBytesInPath = 100 * 1024 * 1024 // 100 MB
+)
+
+// GetAllFilesInPath recursively fetches all file contents under a path using the
+// provided FileReader. Returns a map of filepath -> content for all files found.
+// If the path points to an empty directory, returns an empty map.
+//
+// This function uses fail-fast error handling: any error from ListContents or
+// GetFileContent aborts the entire traversal and returns the error immediately.
+// This differs from gitea.Client.GetAllFilesInPath, which logs errors and continues.
+// The fail-fast contract ensures callers can trust that a nil error means all files
+// were successfully fetched.
+//
+// Resource limits: the traversal is bounded by maxFilesInPath (file count) and
+// maxTotalBytesInPath (total accumulated bytes). The context is checked before each
+// recursive call and file fetch to respect cancellation.
+func GetAllFilesInPath(ctx context.Context, client FileReader, owner, repo, path string) (map[string]string, error) {
+	results := make(map[string]string)
+	totalBytes := 0
+
+	var walk func(string) error
+	walk = func(dir string) error {
+		if err := ctx.Err(); err != nil {
+			return fmt.Errorf("context canceled during traversal: %w", err)
+		}
+
+		entries, err := client.ListContents(ctx, owner, repo, dir)
+		if err != nil {
+			return fmt.Errorf("list contents %q: %w", dir, err)
+		}
+
+		for _, entry := range entries {
+			if err := ctx.Err(); err != nil {
+				return fmt.Errorf("context canceled during traversal: %w", err)
+			}
+
+			switch entry.Type {
+			case "file":
+				if len(results) >= maxFilesInPath {
+					return fmt.Errorf("exceeded max file count (%d) in path %q", maxFilesInPath, path)
+				}
+
+				content, err := client.GetFileContent(ctx, owner, repo, entry.Path, "")
+				if err != nil {
+					return fmt.Errorf("get file %q: %w", entry.Path, err)
+				}
+
+				totalBytes += len(content)
+				if totalBytes > maxTotalBytesInPath {
+					return fmt.Errorf("exceeded max total bytes (%d) in path %q", maxTotalBytesInPath, path)
+				}
+
+				results[entry.Path] = content
+			case "dir":
+				if err := walk(entry.Path); err != nil {
+					return err
+				}
+			}
+		}
+		return nil
+	}
+
+	if err := walk(path); err != nil {
+		return nil, err
+	}
+	return results, nil
+}
+
+// BuildLineToPositionMap parses a unified diff and returns a map of
+// filename -> (new line number -> diff position). The diff position is a
+// 1-indexed offset from the @@ hunk header line for each file.
+// Only lines that appear in the new file (context lines and additions) are mapped.
+// Deletion-only lines are not included.
+func BuildLineToPositionMap(diff string) map[string]map[int]int {
+	result := make(map[string]map[int]int)
+
+	lines := strings.Split(diff, "\n")
+	var currentFile string
+	var position int
+	var newLine int
+
+	for _, line := range lines {
+		// Detect new file in diff
+		if strings.HasPrefix(line, "+++ b/") {
+			currentFile = strings.TrimPrefix(line, "+++ b/")
+			position = 0
+			newLine = 0
+			if result[currentFile] == nil {
+				result[currentFile] = make(map[int]int)
+			}
+			continue
+		}
+
+		// Skip --- lines (old file header)
+		if strings.HasPrefix(line, "--- ") {
+			continue
+		}
+
+		// Skip diff --git lines
+		if strings.HasPrefix(line, "diff --git") {
+			continue
+		}
+
+		// Skip index lines
+		if strings.HasPrefix(line, "index ") {
+			continue
+		}
+
+		// Parse hunk headers
+		if strings.HasPrefix(line, "@@") {
+			position++
+			// Extract new file start line from @@ -a,b +c,d @@
+			newLine = parseHunkNewStart(line)
+			continue
+		}
+
+		// We need a current file to map lines
+		if currentFile == "" {
+			continue
+		}
+
+		// Skip "\ No newline at end of file" markers — these are git diff
+		// metadata and not part of the file content.
+		if strings.HasPrefix(line, `\`) {
+			continue
+		}
+
+		// Process diff content lines
+		if strings.HasPrefix(line, "+") {
+			position++
+			result[currentFile][newLine] = position
+			newLine++
+		} else if strings.HasPrefix(line, "-") {
+			position++
+			// Deletion lines don't map to new line numbers
+		} else if strings.HasPrefix(line, " ") {
+			// Context line (space-prefixed).
+			// Only map if position > 0, which means we've seen a hunk header.
+			// Lines before the first hunk header (position == 0) are not part
+			// of any diff hunk and should be skipped.
+			if position > 0 {
+				position++
+				result[currentFile][newLine] = position
+				newLine++
+			}
+		}
+	}
+
+	return result
+}
+
+// parseHunkNewStart extracts the new-file starting line number from a hunk header.
+// Format: @@ -old_start[,old_count] +new_start[,new_count] @@
+func parseHunkNewStart(hunkLine string) int {
+	// Find the +N part
+	plusIdx := strings.Index(hunkLine, "+")
+	if plusIdx < 0 {
+		return 1
+	}
+	rest := hunkLine[plusIdx+1:]
+
+	// Find the end of the number (first non-digit after +)
+	endIdx := 0
+	for endIdx < len(rest) && rest[endIdx] >= '0' && rest[endIdx] <= '9' {
+		endIdx++
+	}
+
+	if endIdx == 0 {
+		return 1
+	}
+
+	n, err := strconv.Atoi(rest[:endIdx])
+	if err != nil {
+		return 1
+	}
+	return n
+}

vcs/util_test.go

@@ -0,0 +1,331 @@
+package vcs_test
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"testing"
+
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// mockFileReader implements vcs.FileReader for testing.
+type mockFileReader struct {
+	contents map[string][]vcs.ContentEntry // path -> entries
+	files    map[string]string             // path -> content
+}
+
+func (m *mockFileReader) GetFileContent(ctx context.Context, owner, repo, path, ref string) (string, error) {
+	content, ok := m.files[path]
+	if !ok {
+		return "", fmt.Errorf("HTTP 404: file not found: %s", path)
+	}
+	return content, nil
+}
+
+func (m *mockFileReader) ListContents(ctx context.Context, owner, repo, path string) ([]vcs.ContentEntry, error) {
+	entries, ok := m.contents[path]
+	if !ok {
+		return nil, fmt.Errorf("HTTP 404: path not found: %s", path)
+	}
+	return entries, nil
+}
+
+func TestGetAllFilesInPath(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("empty directory", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {},
+			},
+		}
+		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if len(result) != 0 {
+			t.Errorf("expected empty map, got %d entries", len(result))
+		}
+	})
+
+	t.Run("flat directory", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {
+					{Name: "main.go", Path: "src/main.go", Type: "file"},
+					{Name: "util.go", Path: "src/util.go", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				"src/main.go": "package main",
+				"src/util.go": "package main\n// util",
+			},
+		}
+		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if len(result) != 2 {
+			t.Fatalf("expected 2 files, got %d", len(result))
+		}
+		if result["src/main.go"] != "package main" {
+			t.Errorf("main.go content = %q", result["src/main.go"])
+		}
+		if result["src/util.go"] != "package main\n// util" {
+			t.Errorf("util.go content = %q", result["src/util.go"])
+		}
+	})
+
+	t.Run("nested directories", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {
+					{Name: "main.go", Path: "src/main.go", Type: "file"},
+					{Name: "pkg", Path: "src/pkg", Type: "dir"},
+				},
+				"src/pkg": {
+					{Name: "lib.go", Path: "src/pkg/lib.go", Type: "file"},
+					{Name: "sub", Path: "src/pkg/sub", Type: "dir"},
+				},
+				"src/pkg/sub": {
+					{Name: "deep.go", Path: "src/pkg/sub/deep.go", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				"src/main.go":         "package main",
+				"src/pkg/lib.go":      "package pkg",
+				"src/pkg/sub/deep.go": "package sub",
+			},
+		}
+		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if len(result) != 3 {
+			t.Fatalf("expected 3 files, got %d", len(result))
+		}
+		if result["src/main.go"] != "package main" {
+			t.Errorf("main.go content = %q", result["src/main.go"])
+		}
+		if result["src/pkg/lib.go"] != "package pkg" {
+			t.Errorf("lib.go content = %q", result["src/pkg/lib.go"])
+		}
+		if result["src/pkg/sub/deep.go"] != "package sub" {
+			t.Errorf("deep.go content = %q", result["src/pkg/sub/deep.go"])
+		}
+	})
+
+	t.Run("mixed files and dirs", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"root": {
+					{Name: "README.md", Path: "root/README.md", Type: "file"},
+					{Name: "docs", Path: "root/docs", Type: "dir"},
+					{Name: "config.yaml", Path: "root/config.yaml", Type: "file"},
+				},
+				"root/docs": {
+					{Name: "guide.md", Path: "root/docs/guide.md", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				"root/README.md":     "# Hello",
+				"root/config.yaml":   "key: value",
+				"root/docs/guide.md": "## Guide",
+			},
+		}
+		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "root")
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if len(result) != 3 {
+			t.Fatalf("expected 3 files, got %d", len(result))
+		}
+		if result["root/README.md"] != "# Hello" {
+			t.Errorf("README content = %q", result["root/README.md"])
+		}
+		if result["root/docs/guide.md"] != "## Guide" {
+			t.Errorf("guide content = %q", result["root/docs/guide.md"])
+		}
+	})
+}
+
+func TestBuildLineToPositionMap(t *testing.T) {
+	t.Run("single hunk", func(t *testing.T) {
+		diff := "diff --git a/file.go b/file.go\nindex abc..def 100644\n--- a/file.go\n+++ b/file.go\n@@ -1,3 +1,4 @@\n package main\n \n+// new comment\n func main() {}\n"
+		result := vcs.BuildLineToPositionMap(diff)
+		fileMap, ok := result["file.go"]
+		if !ok {
+			t.Fatal("expected file.go in result")
+		}
+		// Hunk header @@ is position 1
+		// Line 1: " package main" -> position 2
+		if fileMap[1] != 2 {
+			t.Errorf("line 1 position = %d, want 2", fileMap[1])
+		}
+		// Line 2: " " (context) -> position 3
+		if fileMap[2] != 3 {
+			t.Errorf("line 2 position = %d, want 3", fileMap[2])
+		}
+		// Line 3: "+// new comment" -> position 4
+		if fileMap[3] != 4 {
+			t.Errorf("line 3 position = %d, want 4", fileMap[3])
+		}
+		// Line 4: " func main() {}" -> position 5
+		if fileMap[4] != 5 {
+			t.Errorf("line 4 position = %d, want 5", fileMap[4])
+		}
+	})
+
+	t.Run("multi hunk", func(t *testing.T) {
+		diff := "diff --git a/file.go b/file.go\n--- a/file.go\n+++ b/file.go\n@@ -1,3 +1,3 @@\n package main\n \n-// old\n+// new\n@@ -10,3 +10,4 @@\n func foo() {\n+\t// added\n \treturn\n }\n"
+		result := vcs.BuildLineToPositionMap(diff)
+		fileMap, ok := result["file.go"]
+		if !ok {
+			t.Fatal("expected file.go in result")
+		}
+		// First hunk: @@ is position 1
+		// Line 1: " package main" -> position 2
+		if fileMap[1] != 2 {
+			t.Errorf("line 1 position = %d, want 2", fileMap[1])
+		}
+		// Line 3: "+// new" -> position 5 (after " ", "-// old" at pos 3,4)
+		if fileMap[3] != 5 {
+			t.Errorf("line 3 position = %d, want 5", fileMap[3])
+		}
+		// Second hunk: @@ is position 6
+		// Line 10: " func foo() {" -> position 7
+		if fileMap[10] != 7 {
+			t.Errorf("line 10 position = %d, want 7", fileMap[10])
+		}
+		// Line 11: "+\t// added" -> position 8
+		if fileMap[11] != 8 {
+			t.Errorf("line 11 position = %d, want 8", fileMap[11])
+		}
+	})
+
+	t.Run("deletion lines not in map", func(t *testing.T) {
+		diff := "diff --git a/file.go b/file.go\n--- a/file.go\n+++ b/file.go\n@@ -1,4 +1,3 @@\n package main\n \n-// deleted line\n func main() {}\n"
+		result := vcs.BuildLineToPositionMap(diff)
+		fileMap, ok := result["file.go"]
+		if !ok {
+			t.Fatal("expected file.go in result")
+		}
+		// Line 1: " package main" -> position 2
+		if fileMap[1] != 2 {
+			t.Errorf("line 1 position = %d, want 2", fileMap[1])
+		}
+		// Line 3 in new file: " func main() {}" -> position 5 (after deletion at pos 4)
+		if fileMap[3] != 5 {
+			t.Errorf("line 3 position = %d, want 5", fileMap[3])
+		}
+		// Should only have 3 entries (lines 1, 2, 3 of new file)
+		if len(fileMap) != 3 {
+			t.Errorf("expected 3 mapped lines, got %d: %v", len(fileMap), fileMap)
+		}
+	})
+
+	t.Run("multiple files", func(t *testing.T) {
+		diff := "diff --git a/a.go b/a.go\n--- a/a.go\n+++ b/a.go\n@@ -1,2 +1,3 @@\n package a\n \n+// file a\ndiff --git a/b.go b/b.go\n--- a/b.go\n+++ b/b.go\n@@ -1,2 +1,3 @@\n package b\n \n+// file b\n"
+		result := vcs.BuildLineToPositionMap(diff)
+		if len(result) != 2 {
+			t.Fatalf("expected 2 files, got %d", len(result))
+		}
+		aMap, ok := result["a.go"]
+		if !ok {
+			t.Fatal("expected a.go in result")
+		}
+		bMap, ok := result["b.go"]
+		if !ok {
+			t.Fatal("expected b.go in result")
+		}
+		// a.go line 3: "+// file a" -> position 4
+		if aMap[3] != 4 {
+			t.Errorf("a.go line 3 position = %d, want 4", aMap[3])
+		}
+		// b.go line 3: "+// file b" -> position 4
+		if bMap[3] != 4 {
+			t.Errorf("b.go line 3 position = %d, want 4", bMap[3])
+		}
+	})
+}
+
+func TestGetAllFilesInPath_ErrorPropagation(t *testing.T) {
+	ctx := context.Background()
+
+	t.Run("ListContents error propagates", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				// "src" not in map, so ListContents will fail
+			},
+		}
+		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err == nil {
+			t.Fatal("expected error, got nil")
+		}
+		if !strings.Contains(err.Error(), "list contents") {
+			t.Errorf("expected error about list contents, got: %v", err)
+		}
+	})
+
+	t.Run("GetFileContent error propagates", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {
+					{Name: "main.go", Path: "src/main.go", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				// "src/main.go" not in files map, so GetFileContent will fail
+			},
+		}
+		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err == nil {
+			t.Fatal("expected error, got nil")
+		}
+		if !strings.Contains(err.Error(), "get file") {
+			t.Errorf("expected error about get file, got: %v", err)
+		}
+	})
+
+	t.Run("nested ListContents error propagates", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {
+					{Name: "pkg", Path: "src/pkg", Type: "dir"},
+				},
+				// "src/pkg" not in map, so recursive ListContents will fail
+			},
+		}
+		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err == nil {
+			t.Fatal("expected error, got nil")
+		}
+		if !strings.Contains(err.Error(), "list contents") {
+			t.Errorf("expected error about list contents, got: %v", err)
+		}
+	})
+
+	t.Run("canceled context propagates", func(t *testing.T) {
+		ctx, cancel := context.WithCancel(context.Background())
+		cancel() // Cancel immediately
+
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {
+					{Name: "main.go", Path: "src/main.go", Type: "file"},
+				},
+			},
+			files: map[string]string{
+				"src/main.go": "package main",
+			},
+		}
+		_, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err == nil {
+			t.Fatal("expected error from canceled context, got nil")
+		}
+		if !strings.Contains(err.Error(), "context canceled") {
+			t.Errorf("expected context cancellation error, got: %v", err)
+		}
+	})
+}