feat(#130): add VCS routing in cmd/review-bot via --vcs-type flag

- Add vcs_client.go with vcsClient interface, giteaClientVCSAdapter, githubClientVCSAdapter
- Add giteaExtendedClient interface for Gitea-specific operations (supersede, resolve, etc.)
- Add --vcs-type flag (gitea|github, default: gitea) with VCS_TYPE env var support
- Replace direct giteaClient usage with vcsClient interface in main.go
- Add verdictToVCSEvent() to map LLM verdict to vcs.ReviewEvent
- Gitea adapter translates vcs.ReviewEvent back to Gitea API format (APPROVE->APPROVED)
- Guard Gitea-specific ops (RequestReviewer, supersede, resolve) with type assertion
- Guard fetchPatterns GetAllFilesInPath with Gitea-only type assertion
- Replace reviewClientAdapter (giteaClientAdapter) for review.GiteaClient interface
- Update main_test.go to use reviewInfo/commitStatusInfo instead of gitea types

cmd/review-bot/main.go

@@ -14,8 +14,10 @@ import (
 
 	"gitea.weiker.me/rodin/review-bot/budget"
 	"gitea.weiker.me/rodin/review-bot/gitea"
+	"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"
@@ -84,6 +86,7 @@ func main() {
 	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)")
+	vcsType := flag.String("vcs-type", envOrDefault("VCS_TYPE", "gitea"), "VCS type: gitea or github")
 	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)")
@@ -168,8 +171,19 @@ func main() {
 		os.Exit(1)
 	}
 
-	// Initialize clients
-	giteaClient := gitea.NewClient(*vcsURL, *reviewerToken)
+	// Initialize VCS client
+	var vcsClientImpl vcsClient
+	switch strings.ToLower(*vcsType) {
+	case "github":
+		vcsClientImpl = newGitHubVCSAdapter(github.NewClient(*reviewerToken, *vcsURL))
+		slog.Info("using GitHub VCS client", "url", *vcsURL)
+	case "gitea", "":
+		vcsClientImpl = newGiteaVCSAdapter(gitea.NewClient(*vcsURL, *reviewerToken))
+		slog.Info("using Gitea VCS client", "url", *vcsURL)
+	default:
+		slog.Error("invalid vcs-type", "type", *vcsType, "valid", "gitea, github")
+		os.Exit(1)
+	}
 	llmClient := llm.NewClient(*llmBaseURL, *llmAPIKey, *llmModel)
 	if *llmTemp < 0 || *llmTemp > 2 {
 		slog.Error("invalid LLM temperature", "temperature", *llmTemp, "range", "0-2")
@@ -207,7 +221,7 @@ func main() {
 	var persona *review.Persona
 	if *personaName != "" {
 		// Try loading from repo first, then fall back to built-in
-		repoPersonas, err := review.LoadRepoPersonas(ctx, newGiteaClientAdapter(giteaClient), owner, repoName)
+		repoPersonas, err := review.LoadRepoPersonas(ctx, newReviewClientAdapter(vcsClientImpl), owner, repoName)
 		if err != nil {
 			slog.Warn("could not load repo personas", "repo", owner+"/"+repoName, "error", err)
 			// Continue with built-in personas only.
@@ -243,7 +257,7 @@ func main() {
 	slog.Info("reviewing pull request", "pr", prNumber, "repo", fmt.Sprintf("%s/%s", owner, repoName))
 
 	// Step 1: Fetch PR metadata
-	pr, err := giteaClient.GetPullRequest(ctx, owner, repoName, prNumber)
+	pr, err := vcsClientImpl.GetPullRequest(ctx, owner, repoName, prNumber)
 	if err != nil {
 		slog.Error("failed to fetch PR", "pr", prNumber, "error", err)
 		os.Exit(1)
@@ -251,7 +265,7 @@ func main() {
 	slog.Info("fetched PR metadata", "pr", prNumber, "title", pr.Title)
 
 	// Step 2: Fetch diff
-	diff, err := giteaClient.GetPullRequestDiff(ctx, owner, repoName, prNumber)
+	diff, err := vcsClientImpl.GetPullRequestDiff(ctx, owner, repoName, prNumber)
 	if err != nil {
 		slog.Error("failed to fetch diff", "pr", prNumber, "error", err)
 		os.Exit(1)
@@ -260,21 +274,21 @@ func main() {
 
 	// Step 3: Fetch full file content for modified files
 	fileContext := ""
-	files, err := giteaClient.GetPullRequestFiles(ctx, owner, repoName, prNumber)
+	files, err := vcsClientImpl.GetPullRequestFiles(ctx, owner, repoName, prNumber)
 	if err != nil {
 		slog.Warn("could not fetch PR files list", "pr", prNumber, "error", err)
 	} else {
-		fileContext = fetchFileContext(ctx, giteaClient, owner, repoName, pr.Head.Ref, files)
+		fileContext = fetchFileContext(ctx, vcsClientImpl, owner, repoName, pr.HeadRef, files)
 		slog.Debug("fetched file context", "files", len(files))
 	}
 
 	// Step 4: Check CI status
 	ciPassed := true
 	ciDetails := ""
-	if pr.Head.Sha != "" {
-		statuses, err := giteaClient.GetCommitStatuses(ctx, owner, repoName, pr.Head.Sha)
+	if pr.HeadSha != "" {
+		statuses, err := vcsClientImpl.GetCommitStatuses(ctx, owner, repoName, pr.HeadSha)
 		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.HeadSha, "error", err)
 		} else {
 			ciPassed, ciDetails = evaluateCIStatus(statuses)
 			slog.Info("CI status checked", "passed", ciPassed)
@@ -284,7 +298,7 @@ func main() {
 	// Step 5: Load conventions file if specified
 	conventions := ""
 	if *conventionsFile != "" {
-		content, err := giteaClient.GetFileContent(ctx, owner, repoName, *conventionsFile)
+		content, err := vcsClientImpl.GetFileContent(ctx, owner, repoName, *conventionsFile)
 		if err != nil {
 			slog.Warn("could not load conventions file", "file", *conventionsFile, "error", err)
 		} else {
@@ -296,7 +310,7 @@ func main() {
 	// Step 6: Load patterns from external repo if specified
 	patterns := ""
 	if *patternsRepo != "" {
-		patterns = fetchPatterns(ctx, giteaClient, *patternsRepo, *patternsFiles)
+		patterns = fetchPatterns(ctx, vcsClientImpl, *patternsRepo, *patternsFiles)
 		slog.Debug("loaded patterns", "repo", *patternsRepo, "bytes", len(patterns))
 	}
 
@@ -389,15 +403,15 @@ func main() {
 	}
 
 	// Add commit footer so readers know which commit was evaluated
-	if pr.Head.Sha != "" {
-		shortSHA := pr.Head.Sha
+	if pr.HeadSha != "" {
+		shortSHA := pr.HeadSha
 		if len(shortSHA) > 8 {
 			shortSHA = shortSHA[:8]
 		}
 		reviewBody += fmt.Sprintf("\n\n---\n*Evaluated against %s*", shortSHA)
 	}
 
-	event := review.GiteaEvent(result.Verdict)
+	event := verdictToVCSEvent(result.Verdict)
 
 	if *dryRun {
 		fmt.Println("--- DRY RUN ---")
@@ -409,14 +423,14 @@ 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.HeadSha
 	var currentSHA string
-	currentPR, err := giteaClient.GetPullRequest(ctx, owner, repoName, prNumber)
+	currentPR, err := vcsClientImpl.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.HeadSha
 	}
 	if shouldSkipStaleReview(evaluatedSHA, currentSHA) {
 		slog.Warn("HEAD moved during review — skipping stale review",
@@ -427,28 +441,30 @@ func main() {
 	}
 
 	// Map findings to inline comments for lines present in the diff
-	diffRanges := gitea.ParseDiffNewLines(diff)
-	var inlineComments []gitea.ReviewComment
-	for _, f := range result.Findings {
-		if f.File != "" && f.Line > 0 && diffRanges.Contains(f.File, f.Line) {
-			inlineComments = append(inlineComments, gitea.ReviewComment{
-				Path:        f.File,
-				NewPosition: int64(f.Line),
-				Body:        fmt.Sprintf("**[%s]** %s", f.Severity, f.Finding),
-			})
+	var inlineComments []vcs.ReviewComment
+	if ext, ok := vcsClientImpl.(giteaExtendedClient); ok {
+		diffRanges := ext.ParseDiffNewLines(diff)
+		for _, f := range result.Findings {
+			if f.File != "" && f.Line > 0 && diffRanges.Contains(f.File, f.Line) {
+				inlineComments = append(inlineComments, vcs.ReviewComment{
+					Path:     f.File,
+					Position: f.Line,
+					Body:     fmt.Sprintf("**[%s]** %s", f.Severity, f.Finding),
+				})
+			}
+		}
+		if len(inlineComments) > 0 {
+			slog.Debug("attaching inline comments", "count", len(inlineComments))
 		}
-	}
-	if len(inlineComments) > 0 {
-		slog.Debug("attaching inline comments", "count", len(inlineComments))
 	}
 
 	// --- 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 []gitea.Review
+	var oldReviews []reviewInfo
 	if *reviewerName != "" {
-		existingReviews, err := giteaClient.ListReviews(ctx, owner, repoName, prNumber)
+		existingReviews, err := vcsClientImpl.ListReviews(ctx, owner, repoName, prNumber)
 		if err != nil {
 			slog.Warn("could not list existing reviews", "pr", prNumber, "error", err)
 		} else {
@@ -461,20 +477,27 @@ func main() {
 	}
 
 	// Self-request as reviewer (ensures we appear in required-reviewer checks)
-	authUser, err := giteaClient.GetAuthenticatedUser(ctx)
+	authUser, err := vcsClientImpl.GetAuthenticatedUser(ctx)
 	if err != nil {
 		slog.Warn("could not determine authenticated user for reviewer self-request", "error", err)
 	} else if authUser != "" {
-		if err := giteaClient.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)
+		if ext, ok := vcsClientImpl.(giteaExtendedClient); ok {
+			if err := ext.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)
+			}
 		}
 	}
 
 	// POST new review
 	slog.Info("posting review", "event", event, "pr", prNumber)
-	posted, err := giteaClient.PostReview(ctx, owner, repoName, prNumber, event, reviewBody, evaluatedSHA, inlineComments)
+	posted, err := vcsClientImpl.PostReview(ctx, owner, repoName, prNumber, vcs.ReviewRequest{
+		Body:     reviewBody,
+		Event:    event,
+		CommitID: evaluatedSHA,
+		Comments: inlineComments,
+	})
 	if err != nil {
 		slog.Error("failed to post review", "pr", prNumber, "event", event, "error", err)
 		os.Exit(1)
@@ -484,21 +507,26 @@ func main() {
 	// Supersede all old reviews with link to the new one
 	if len(oldReviews) > 0 {
 		newReviewURL := fmt.Sprintf("%s/%s/%s/pulls/%d#pullrequestreview-%d", strings.TrimRight(*vcsURL, "/"), owner, repoName, prNumber, posted.ID)
+		ext, hasExt := vcsClientImpl.(giteaExtendedClient)
 		for _, oldReview := range oldReviews {
-			cid, err := giteaClient.GetTimelineReviewCommentIDForReview(ctx, owner, repoName, prNumber, oldReview.ID)
+			if !hasExt {
+				slog.Debug("VCS client does not support review supersede; skipping", "review_id", oldReview.ID)
+				continue
+			}
+			cid, err := ext.GetTimelineReviewCommentIDForReview(ctx, owner, repoName, 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 := giteaClient.EditComment(ctx, owner, repoName, cid, supersededBody); err != nil {
+			if err := ext.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 := giteaClient.ListReviewComments(ctx, owner, repoName, prNumber, oldReview.ID)
+			oldComments, err := ext.ListReviewComments(ctx, owner, repoName, prNumber, oldReview.ID)
 			if err != nil {
 				slog.Warn("could not list old review comments for resolution", "review_id", oldReview.ID, "error", err)
 				continue
@@ -508,7 +536,7 @@ func main() {
 				if c.ID == 0 {
 					continue
 				}
-				if err := giteaClient.ResolveComment(ctx, owner, repoName, c.ID); err != nil {
+				if err := ext.ResolveComment(ctx, owner, repoName, c.ID); err != nil {
 					slog.Debug("could not resolve inline comment", "comment_id", c.ID, "error", err)
 					failed++
 				} else {
@@ -527,7 +555,7 @@ func main() {
 }
 
 // fetchFileContext fetches the full content of modified files from the PR branch.
-func fetchFileContext(ctx context.Context, client *gitea.Client, owner, repo, ref string, files []gitea.ChangedFile) string {
+func fetchFileContext(ctx context.Context, client vcsClient, owner, repo, ref string, files []changedFileInfo) string {
 	var sb strings.Builder
 	for _, f := range files {
 		if ctx.Err() != nil {
@@ -554,7 +582,7 @@ func fetchFileContext(ctx context.Context, client *gitea.Client, owner, repo, re
 // 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 *gitea.Client, patternsRepo, patternsFiles string) string {
+func fetchPatterns(ctx context.Context, client vcsClient, patternsRepo, patternsFiles string) string {
 	var sb strings.Builder
 
 	repos := strings.Split(patternsRepo, ",")
@@ -591,8 +619,13 @@ func fetchPatterns(ctx context.Context, client *gitea.Client, patternsRepo, patt
 		var repoLoadedFiles []string
 		var repoSkippedFiles []string
 
+		giteaRaw, isGitea := client.(*giteaClientVCSAdapter)
+		if !isGitea {
+			slog.Warn("patterns fetching is only supported with the Gitea VCS client; skipping", "repo", repoRef)
+			continue
+		}
 		for _, path := range paths {
-			files, err := client.GetAllFilesInPath(ctx, owner, repo, path)
+			files, err := giteaRaw.client.GetAllFilesInPath(ctx, owner, repo, path)
 			if err != nil {
 				slog.Warn("could not fetch patterns", "path", path, "repo", repoRef, "error", err)
 				continue
@@ -631,7 +664,7 @@ func isPatternFile(path string) bool {
 }
 
 // evaluateCIStatus checks if all CI statuses indicate success.
-func evaluateCIStatus(statuses []gitea.CommitStatus) (passed bool, details string) {
+func evaluateCIStatus(statuses []commitStatusInfo) (passed bool, details string) {
 	if len(statuses) == 0 {
 		return true, "no CI statuses found"
 	}
@@ -769,7 +802,7 @@ func buildSupersededBody(originalBody, commitSHA, newReviewURL, sentinel string)
 // Gitea user. This indicates misconfiguration where two roles share a token
 // instead of having separate Gitea accounts. Returns true if shared token
 // detected (caller should skip update-in-place logic to avoid clobbering).
-func hasSharedToken(reviews []gitea.Review, ownSentinel string) bool {
+func hasSharedToken(reviews []reviewInfo, ownSentinel string) bool {
 	ownLogin := ""
 	for _, r := range reviews {
 		if strings.Contains(r.Body, ownSentinel) {
@@ -807,8 +840,8 @@ func extractSentinelName(body string) string {
 }
 
 // findOwnReview locates the most recent non-superseded review matching the sentinel.
-func findOwnReview(reviews []gitea.Review, sentinel string) *gitea.Review {
-	var best *gitea.Review
+func findOwnReview(reviews []reviewInfo, sentinel string) *reviewInfo {
+	var best *reviewInfo
 	for i := range reviews {
 		if !strings.Contains(reviews[i].Body, sentinel) {
 			continue
@@ -824,8 +857,8 @@ func findOwnReview(reviews []gitea.Review, sentinel string) *gitea.Review {
 }
 
 // findAllOwnReviews returns all non-superseded reviews matching the sentinel.
-func findAllOwnReviews(reviews []gitea.Review, sentinel string) []gitea.Review {
-	var result []gitea.Review
+func findAllOwnReviews(reviews []reviewInfo, sentinel string) []reviewInfo {
+	var result []reviewInfo
 	for i := range reviews {
 		if !strings.Contains(reviews[i].Body, sentinel) {
 			continue
@@ -838,6 +871,22 @@ func findAllOwnReviews(reviews []gitea.Review, sentinel string) []gitea.Review {
 	return result
 }
 
+// verdictToVCSEvent converts a review verdict string to a vcs.ReviewEvent.
+// The verdict comes from the LLM result and uses values: "APPROVE", "REQUEST_CHANGES",
+// or any other string (treated as COMMENT).
+// vcs.ReviewEvent constants follow GitHub API format ("APPROVE", "REQUEST_CHANGES", "COMMENT").
+// The Gitea adapter translates these back to Gitea format ("APPROVED", etc.) before posting.
+func verdictToVCSEvent(verdict string) vcs.ReviewEvent {
+	switch verdict {
+	case "APPROVE":
+		return vcs.ReviewEventApprove
+	case "REQUEST_CHANGES":
+		return vcs.ReviewEventRequestChanges
+	default:
+		return vcs.ReviewEventComment
+	}
+}
+
 // shouldSkipStaleReview reports whether to skip posting because HEAD moved.
 // Returns true (skip) if evaluatedSHA differs from currentSHA.
 // Returns false (don't skip) if:
@@ -851,16 +900,17 @@ func shouldSkipStaleReview(evaluatedSHA, currentSHA string) bool {
 	return evaluatedSHA != currentSHA
 }
 
-// giteaClientAdapter adapts gitea.Client to review.GiteaClient interface.
-type giteaClientAdapter struct {
-	client *gitea.Client
+// reviewClientAdapter adapts a vcsClient to review.GiteaClient for persona loading.
+// The review package only needs ListContents and GetFileContent, which all vcsClients provide.
+type reviewClientAdapter struct {
+	client vcsClient
 }
 
-func newGiteaClientAdapter(c *gitea.Client) *giteaClientAdapter {
-	return &giteaClientAdapter{client: c}
+func newReviewClientAdapter(c vcsClient) *reviewClientAdapter {
+	return &reviewClientAdapter{client: c}
 }
 
-func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]review.ContentEntry, error) {
+func (a *reviewClientAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]review.ContentEntry, error) {
 	entries, err := a.client.ListContents(ctx, owner, repo, path)
 	if err != nil {
 		return nil, err
@@ -876,6 +926,6 @@ func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path
 	return result, nil
 }
 
-func (a *giteaClientAdapter) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
+func (a *reviewClientAdapter) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
 	return a.client.GetFileContent(ctx, owner, repo, filepath)
 }

cmd/review-bot/main_test.go

@@ -10,7 +10,7 @@ import (
 	"strings"
 	"testing"
 
-	"gitea.weiker.me/rodin/review-bot/gitea"
+	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 func TestValidateReviewerName(t *testing.T) {
@@ -154,14 +154,14 @@ func TestValidateWorkspacePath(t *testing.T) {
 	}
 }
 
-func makeReview(id int64, login, state string, stale bool, body string) gitea.Review {
-	r := gitea.Review{
+func makeReview(id int64, login, state string, stale bool, body string) reviewInfo {
+	r := reviewInfo{
 		ID:    id,
 		Body:  body,
 		State: state,
 		Stale: stale,
 	}
-	r.User.Login = login
+	r.User = vcs.UserInfo{Login: login}
 	return r
 }
 
@@ -216,7 +216,7 @@ func TestBuildSupersededBodyShortSHA(t *testing.T) {
 func TestFindOwnReview(t *testing.T) {
 	tests := []struct {
 		name     string
-		reviews  []gitea.Review
+		reviews  []reviewInfo
 		sentinel string
 		wantID   int64
 		wantNil  bool
@@ -229,7 +229,7 @@ func TestFindOwnReview(t *testing.T) {
 		},
 		{
 			name: "found by sentinel",
-			reviews: []gitea.Review{
+			reviews: []reviewInfo{
 				makeReview(42, "bot", "APPROVED", false, "review body\n<!-- review-bot:sonnet -->"),
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
@@ -237,7 +237,7 @@ func TestFindOwnReview(t *testing.T) {
 		},
 		{
 			name: "wrong sentinel",
-			reviews: []gitea.Review{
+			reviews: []reviewInfo{
 				makeReview(42, "bot", "APPROVED", false, "body\n<!-- review-bot:gpt -->"),
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
@@ -245,7 +245,7 @@ func TestFindOwnReview(t *testing.T) {
 		},
 		{
 			name: "multiple reviews, returns first match",
-			reviews: []gitea.Review{
+			reviews: []reviewInfo{
 				makeReview(10, "bot", "APPROVED", false, "old\n<!-- review-bot:gpt -->"),
 				makeReview(20, "bot", "APPROVED", false, "new\n<!-- review-bot:sonnet -->"),
 			},
@@ -254,7 +254,7 @@ func TestFindOwnReview(t *testing.T) {
 		},
 		{
 			name: "skips superseded review",
-			reviews: []gitea.Review{
+			reviews: []reviewInfo{
 				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 -->"),
 			},
@@ -263,7 +263,7 @@ func TestFindOwnReview(t *testing.T) {
 		},
 		{
 			name: "only superseded reviews exist",
-			reviews: []gitea.Review{
+			reviews: []reviewInfo{
 				makeReview(10, "bot", "APPROVED", false, "~~Original review~~\n\n<!-- review-bot:sonnet -->"),
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
@@ -271,7 +271,7 @@ func TestFindOwnReview(t *testing.T) {
 		},
 		{
 			name: "picks highest ID among matches",
-			reviews: []gitea.Review{
+			reviews: []reviewInfo{
 				makeReview(50, "bot", "APPROVED", false, "v1\n<!-- review-bot:sonnet -->"),
 				makeReview(30, "bot", "APPROVED", false, "v0\n<!-- review-bot:sonnet -->"),
 			},
@@ -302,7 +302,7 @@ func TestFindOwnReview(t *testing.T) {
 func TestHasSharedToken(t *testing.T) {
 	tests := []struct {
 		name     string
-		reviews  []gitea.Review
+		reviews  []reviewInfo
 		sentinel string
 		want     bool
 	}{
@@ -314,36 +314,36 @@ func TestHasSharedToken(t *testing.T) {
 		},
 		{
 			name: "no own review yet - cannot detect",
-			reviews: []gitea.Review{
-				{ID: 1, User: struct{ Login string `json:"login"` }{Login: "other"}, Body: "<!-- review-bot:gpt --> body"},
+			reviews: []reviewInfo{
+				{ID: 1, User: vcs.UserInfo{Login: "other"}, Body: "<!-- review-bot:gpt --> body"},
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
 			want:     false,
 		},
 		{
 			name: "separate users - no shared token",
-			reviews: []gitea.Review{
-				{ID: 1, User: struct{ Login string `json:"login"` }{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:sonnet --> body"},
-				{ID: 2, User: struct{ Login string `json:"login"` }{Login: "security-review-bot"}, Body: "<!-- review-bot:security --> body"},
+			reviews: []reviewInfo{
+				{ID: 1, User: vcs.UserInfo{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:sonnet --> body"},
+				{ID: 2, User: vcs.UserInfo{Login: "security-review-bot"}, Body: "<!-- review-bot:security --> body"},
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
 			want:     false,
 		},
 		{
 			name: "shared token detected - same user different sentinels",
-			reviews: []gitea.Review{
-				{ID: 1, User: struct{ Login string `json:"login"` }{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:sonnet --> body"},
-				{ID: 2, User: struct{ Login string `json:"login"` }{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:security --> body"},
+			reviews: []reviewInfo{
+				{ID: 1, User: vcs.UserInfo{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:sonnet --> body"},
+				{ID: 2, User: vcs.UserInfo{Login: "sonnet-review-bot"}, Body: "<!-- review-bot:security --> body"},
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
 			want:     true,
 		},
 		{
 			name: "three roles same user",
-			reviews: []gitea.Review{
-				{ID: 1, User: struct{ Login string `json:"login"` }{Login: "bot"}, Body: "<!-- review-bot:sonnet --> body"},
-				{ID: 2, User: struct{ Login string `json:"login"` }{Login: "bot"}, Body: "<!-- review-bot:security --> body"},
-				{ID: 3, User: struct{ Login string `json:"login"` }{Login: "bot"}, Body: "<!-- review-bot:gpt --> body"},
+			reviews: []reviewInfo{
+				{ID: 1, User: vcs.UserInfo{Login: "bot"}, Body: "<!-- review-bot:sonnet --> body"},
+				{ID: 2, User: vcs.UserInfo{Login: "bot"}, Body: "<!-- review-bot:security --> body"},
+				{ID: 3, User: vcs.UserInfo{Login: "bot"}, Body: "<!-- review-bot:gpt --> body"},
 			},
 			sentinel: "<!-- review-bot:sonnet -->",
 			want:     true,
@@ -553,7 +553,7 @@ func TestBuildPatternPaths(t *testing.T) {
 func TestEvaluateCIStatus(t *testing.T) {
 	tests := []struct {
 		name       string
-		statuses   []gitea.CommitStatus
+		statuses   []commitStatusInfo
 		wantPassed bool
 		wantSubstr string
 	}{
@@ -565,7 +565,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "all success",
-			statuses: []gitea.CommitStatus{
+			statuses: []commitStatusInfo{
 				{Status: "success", Context: "ci/build", Description: "Build passed"},
 				{Status: "success", Context: "ci/test", Description: "Tests passed"},
 			},
@@ -574,7 +574,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "one failure",
-			statuses: []gitea.CommitStatus{
+			statuses: []commitStatusInfo{
 				{Status: "success", Context: "ci/build", Description: "Build passed"},
 				{Status: "failure", Context: "ci/test", Description: "Tests failed"},
 			},
@@ -583,7 +583,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "error status",
-			statuses: []gitea.CommitStatus{
+			statuses: []commitStatusInfo{
 				{Status: "error", Context: "ci/lint", Description: "Lint error"},
 			},
 			wantPassed: false,
@@ -591,7 +591,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "pending treated as not-failed",
-			statuses: []gitea.CommitStatus{
+			statuses: []commitStatusInfo{
 				{Status: "pending", Context: "ci/build", Description: "In progress"},
 				{Status: "success", Context: "ci/test", Description: "Tests passed"},
 			},
@@ -600,7 +600,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "multiple failures",
-			statuses: []gitea.CommitStatus{
+			statuses: []commitStatusInfo{
 				{Status: "failure", Context: "ci/build", Description: "Build failed"},
 				{Status: "failure", Context: "ci/test", Description: "Tests failed"},
 			},
@@ -609,7 +609,7 @@ func TestEvaluateCIStatus(t *testing.T) {
 		},
 		{
 			name: "mixed with pending and failure",
-			statuses: []gitea.CommitStatus{
+			statuses: []commitStatusInfo{
 				{Status: "success", Context: "ci/build", Description: "Build passed"},
 				{Status: "pending", Context: "ci/deploy", Description: "Deploying"},
 				{Status: "failure", Context: "ci/test", Description: "Tests failed"},
@@ -997,7 +997,7 @@ func cleanEnv() []string {
 }
 
 func TestFindAllOwnReviews(t *testing.T) {
-	reviews := []gitea.Review{
+	reviews := []reviewInfo{
 		{ID: 1, Body: "<!-- review-bot:sonnet -->\nfirst review"},
 		{ID: 2, Body: "<!-- review-bot:gpt -->\nother bot"},
 		{ID: 3, Body: "<!-- review-bot:sonnet -->\nsecond review"},

cmd/review-bot/vcs_client.go

@@ -0,0 +1,405 @@
+package main
+
+import (
+	"context"
+
+	"gitea.weiker.me/rodin/review-bot/gitea"
+	"gitea.weiker.me/rodin/review-bot/github"
+	"gitea.weiker.me/rodin/review-bot/vcs"
+)
+
+// vcsClient is the unified interface for VCS operations used by the review flow.
+// Both gitea.Client and github.Client satisfy this interface via their respective adapters.
+type vcsClient interface {
+	// GetPullRequest fetches PR metadata.
+	GetPullRequest(ctx context.Context, owner, repo string, number int) (*pullRequestInfo, error)
+
+	// GetPullRequestDiff fetches the unified diff.
+	GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error)
+
+	// GetPullRequestFiles fetches the list of changed files.
+	GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]changedFileInfo, error)
+
+	// GetCommitStatuses fetches CI statuses for a commit.
+	GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]commitStatusInfo, error)
+
+	// GetFileContent fetches the content of a file at HEAD.
+	GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error)
+
+	// GetFileContentRef fetches the content of a file at a given ref.
+	GetFileContentRef(ctx context.Context, owner, repo, filepath, ref string) (string, error)
+
+	// ListContents lists the files and directories at a path.
+	ListContents(ctx context.Context, owner, repo, path string) ([]contentEntryInfo, error)
+
+	// ListReviews returns all reviews for a PR.
+	ListReviews(ctx context.Context, owner, repo string, number int) ([]reviewInfo, error)
+
+	// PostReview submits a review.
+	PostReview(ctx context.Context, owner, repo string, number int, req vcs.ReviewRequest) (*reviewInfo, error)
+
+	// GetAuthenticatedUser returns the login of the authenticated user.
+	GetAuthenticatedUser(ctx context.Context) (string, error)
+}
+
+// giteaExtendedClient is implemented by the Gitea adapter and exposes
+// Gitea-specific operations that have no GitHub equivalent in the current scope.
+// Callers should type-assert to this interface and skip gracefully when it is absent.
+type giteaExtendedClient interface {
+	// RequestReviewer adds the authenticated user as a reviewer on a PR.
+	RequestReviewer(ctx context.Context, owner, repo string, number int, user string) error
+
+	// GetTimelineReviewCommentIDForReview maps a review ID to its timeline comment ID.
+	GetTimelineReviewCommentIDForReview(ctx context.Context, owner, repo string, number int, reviewID int64) (int64, error)
+
+	// EditComment updates the body of an existing PR comment.
+	EditComment(ctx context.Context, owner, repo string, commentID int64, body string) error
+
+	// ListReviewComments lists the inline comments attached to a review.
+	ListReviewComments(ctx context.Context, owner, repo string, number int, reviewID int64) ([]inlineCommentInfo, error)
+
+	// ResolveComment marks an inline comment as resolved.
+	ResolveComment(ctx context.Context, owner, repo string, commentID int64) error
+
+	// ParseDiffNewLines returns the diff line ranges for inline comment positioning.
+	ParseDiffNewLines(diff string) diffLineRanges
+}
+
+// Shared adapter types to avoid duplicating gitea/github-specific types throughout main.go.
+
+type pullRequestInfo struct {
+	Title   string
+	Body    string
+	HeadSha string
+	HeadRef string
+}
+
+type changedFileInfo struct {
+	Filename string
+	Status   string
+}
+
+type commitStatusInfo struct {
+	Status      string
+	Context     string
+	Description string
+	TargetURL   string
+}
+
+type contentEntryInfo struct {
+	Name string
+	Path string
+	Type string
+}
+
+type reviewInfo struct {
+	ID       int64
+	Body     string
+	User     vcs.UserInfo
+	State    string
+	CommitID string
+	Stale    bool
+}
+
+type inlineCommentInfo struct {
+	ID          int64
+	Path        string
+	NewPosition int64
+	Body        string
+}
+
+// diffLineRanges is a type alias for gitea.DiffLineRanges to allow the
+// extended client interface to be defined without importing gitea directly.
+// In practice, only the giteaClientVCSAdapter returns this type, and callers
+// that use it will already have performed the type assertion.
+type diffLineRanges = *gitea.DiffLineRanges
+
+// --- Gitea adapter ---
+
+// giteaClientVCSAdapter wraps gitea.Client to satisfy the vcsClient interface.
+// It also implements giteaExtendedClient for Gitea-specific operations.
+type giteaClientVCSAdapter struct {
+	client *gitea.Client
+}
+
+func newGiteaVCSAdapter(c *gitea.Client) *giteaClientVCSAdapter {
+	return &giteaClientVCSAdapter{client: c}
+}
+
+func (a *giteaClientVCSAdapter) GetPullRequest(ctx context.Context, owner, repo string, number int) (*pullRequestInfo, error) {
+	pr, err := a.client.GetPullRequest(ctx, owner, repo, number)
+	if err != nil {
+		return nil, err
+	}
+	return &pullRequestInfo{
+		Title:   pr.Title,
+		Body:    pr.Body,
+		HeadSha: pr.Head.Sha,
+		HeadRef: pr.Head.Ref,
+	}, nil
+}
+
+func (a *giteaClientVCSAdapter) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
+	return a.client.GetPullRequestDiff(ctx, owner, repo, number)
+}
+
+func (a *giteaClientVCSAdapter) GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]changedFileInfo, error) {
+	files, err := a.client.GetPullRequestFiles(ctx, owner, repo, number)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]changedFileInfo, len(files))
+	for i, f := range files {
+		result[i] = changedFileInfo{Filename: f.Filename, Status: f.Status}
+	}
+	return result, nil
+}
+
+func (a *giteaClientVCSAdapter) GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]commitStatusInfo, error) {
+	statuses, err := a.client.GetCommitStatuses(ctx, owner, repo, sha)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]commitStatusInfo, len(statuses))
+	for i, s := range statuses {
+		result[i] = commitStatusInfo{
+			Status:      s.Status,
+			Context:     s.Context,
+			Description: s.Description,
+			TargetURL:   s.TargetURL,
+		}
+	}
+	return result, nil
+}
+
+func (a *giteaClientVCSAdapter) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
+	return a.client.GetFileContent(ctx, owner, repo, filepath)
+}
+
+func (a *giteaClientVCSAdapter) GetFileContentRef(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
+	return a.client.GetFileContentRef(ctx, owner, repo, filepath, ref)
+}
+
+func (a *giteaClientVCSAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]contentEntryInfo, error) {
+	entries, err := a.client.ListContents(ctx, owner, repo, path)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]contentEntryInfo, len(entries))
+	for i, e := range entries {
+		result[i] = contentEntryInfo{Name: e.Name, Path: e.Path, Type: e.Type}
+	}
+	return result, nil
+}
+
+func (a *giteaClientVCSAdapter) ListReviews(ctx context.Context, owner, repo string, number int) ([]reviewInfo, error) {
+	reviews, err := a.client.ListReviews(ctx, owner, repo, number)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]reviewInfo, len(reviews))
+	for i, r := range reviews {
+		result[i] = reviewInfo{
+			ID:       r.ID,
+			Body:     r.Body,
+			User:     vcs.UserInfo{Login: r.User.Login},
+			State:    r.State,
+			CommitID: r.CommitID,
+			Stale:    r.Stale,
+		}
+	}
+	return result, nil
+}
+
+func (a *giteaClientVCSAdapter) PostReview(ctx context.Context, owner, repo string, number int, req vcs.ReviewRequest) (*reviewInfo, error) {
+	// Translate vcs.ReviewComment to gitea.ReviewComment.
+	// The Gitea API uses NewPosition instead of Position.
+	var comments []gitea.ReviewComment
+	for _, c := range req.Comments {
+		comments = append(comments, gitea.ReviewComment{
+			Path:        c.Path,
+			NewPosition: int64(c.Position),
+			Body:        c.Body,
+		})
+	}
+
+	// Translate vcs.ReviewEvent (GitHub format) to Gitea API event string.
+	// vcs uses "APPROVE"; Gitea API expects "APPROVED".
+	var event string
+	switch req.Event {
+	case vcs.ReviewEventApprove:
+		event = "APPROVED"
+	case vcs.ReviewEventRequestChanges:
+		event = "REQUEST_CHANGES"
+	default:
+		event = "COMMENT"
+	}
+
+	posted, err := a.client.PostReview(ctx, owner, repo, number, event, req.Body, req.CommitID, comments)
+	if err != nil {
+		return nil, err
+	}
+	return &reviewInfo{
+		ID:       posted.ID,
+		Body:     posted.Body,
+		User:     vcs.UserInfo{Login: posted.User.Login},
+		State:    posted.State,
+		CommitID: posted.CommitID,
+	}, nil
+}
+
+func (a *giteaClientVCSAdapter) GetAuthenticatedUser(ctx context.Context) (string, error) {
+	return a.client.GetAuthenticatedUser(ctx)
+}
+
+// giteaExtendedClient implementation:
+
+func (a *giteaClientVCSAdapter) RequestReviewer(ctx context.Context, owner, repo string, number int, user string) error {
+	return a.client.RequestReviewer(ctx, owner, repo, number, user)
+}
+
+func (a *giteaClientVCSAdapter) GetTimelineReviewCommentIDForReview(ctx context.Context, owner, repo string, number int, reviewID int64) (int64, error) {
+	return a.client.GetTimelineReviewCommentIDForReview(ctx, owner, repo, number, reviewID)
+}
+
+func (a *giteaClientVCSAdapter) EditComment(ctx context.Context, owner, repo string, commentID int64, body string) error {
+	return a.client.EditComment(ctx, owner, repo, commentID, body)
+}
+
+func (a *giteaClientVCSAdapter) ListReviewComments(ctx context.Context, owner, repo string, number int, reviewID int64) ([]inlineCommentInfo, error) {
+	comments, err := a.client.ListReviewComments(ctx, owner, repo, number, reviewID)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]inlineCommentInfo, len(comments))
+	for i, c := range comments {
+		result[i] = inlineCommentInfo{
+			ID:          c.ID,
+			Path:        c.Path,
+			NewPosition: c.NewPosition,
+			Body:        c.Body,
+		}
+	}
+	return result, nil
+}
+
+func (a *giteaClientVCSAdapter) ResolveComment(ctx context.Context, owner, repo string, commentID int64) error {
+	return a.client.ResolveComment(ctx, owner, repo, commentID)
+}
+
+func (a *giteaClientVCSAdapter) ParseDiffNewLines(diff string) diffLineRanges {
+	return gitea.ParseDiffNewLines(diff)
+}
+
+// --- GitHub adapter ---
+
+// githubClientVCSAdapter wraps github.Client to satisfy the vcsClient interface.
+type githubClientVCSAdapter struct {
+	client *github.Client
+}
+
+func newGitHubVCSAdapter(c *github.Client) *githubClientVCSAdapter {
+	return &githubClientVCSAdapter{client: c}
+}
+
+func (a *githubClientVCSAdapter) GetPullRequest(ctx context.Context, owner, repo string, number int) (*pullRequestInfo, error) {
+	pr, err := a.client.GetPullRequest(ctx, owner, repo, number)
+	if err != nil {
+		return nil, err
+	}
+	return &pullRequestInfo{
+		Title:   pr.Title,
+		Body:    pr.Body,
+		HeadSha: pr.Head.Sha,
+		HeadRef: pr.Head.Ref,
+	}, nil
+}
+
+func (a *githubClientVCSAdapter) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
+	return a.client.GetPullRequestDiff(ctx, owner, repo, number)
+}
+
+func (a *githubClientVCSAdapter) GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]changedFileInfo, error) {
+	files, err := a.client.GetPullRequestFiles(ctx, owner, repo, number)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]changedFileInfo, len(files))
+	for i, f := range files {
+		result[i] = changedFileInfo{Filename: f.Filename, Status: f.Status}
+	}
+	return result, nil
+}
+
+func (a *githubClientVCSAdapter) GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]commitStatusInfo, error) {
+	statuses, err := a.client.GetCommitStatuses(ctx, owner, repo, sha)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]commitStatusInfo, len(statuses))
+	for i, s := range statuses {
+		result[i] = commitStatusInfo{
+			Status:      s.Status,
+			Context:     s.Context,
+			Description: s.Description,
+			TargetURL:   s.TargetURL,
+		}
+	}
+	return result, nil
+}
+
+func (a *githubClientVCSAdapter) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
+	return a.client.GetFileContent(ctx, owner, repo, filepath)
+}
+
+func (a *githubClientVCSAdapter) GetFileContentRef(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
+	return a.client.GetFileContentRef(ctx, owner, repo, filepath, ref)
+}
+
+func (a *githubClientVCSAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]contentEntryInfo, error) {
+	entries, err := a.client.ListContents(ctx, owner, repo, path)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]contentEntryInfo, len(entries))
+	for i, e := range entries {
+		result[i] = contentEntryInfo{Name: e.Name, Path: e.Path, Type: e.Type}
+	}
+	return result, nil
+}
+
+func (a *githubClientVCSAdapter) ListReviews(ctx context.Context, owner, repo string, number int) ([]reviewInfo, error) {
+	reviews, err := a.client.ListReviews(ctx, owner, repo, number)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]reviewInfo, len(reviews))
+	for i, r := range reviews {
+		result[i] = reviewInfo{
+			ID:       r.ID,
+			Body:     r.Body,
+			User:     r.User,
+			State:    r.State,
+			CommitID: r.CommitID,
+		}
+	}
+	return result, nil
+}
+
+func (a *githubClientVCSAdapter) PostReview(ctx context.Context, owner, repo string, number int, req vcs.ReviewRequest) (*reviewInfo, error) {
+	posted, err := a.client.PostReview(ctx, owner, repo, number, req)
+	if err != nil {
+		return nil, err
+	}
+	return &reviewInfo{
+		ID:       posted.ID,
+		Body:     posted.Body,
+		User:     posted.User,
+		State:    posted.State,
+		CommitID: posted.CommitID,
+	}, nil
+}
+
+func (a *githubClientVCSAdapter) GetAuthenticatedUser(ctx context.Context) (string, error) {
+	return a.client.GetAuthenticatedUser(ctx)
+}

github/review.go

@@ -90,13 +90,13 @@ func (c *Client) PostReview(ctx context.Context, owner, repo string, number int,
 		c.baseURL, url.PathEscape(owner), url.PathEscape(repo), number)
 
 	payload := postReviewRequest{
-		Body:  req.Body,
-		Event: string(req.Event),
+		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; we extract it from the first comment that supplies one and
-	// reject the request if any other comment disagrees.
+	// Build the comments in one pass. Inline comment CommitIDs must match the
+	// review-level CommitID; reject if any disagree.
 	for _, comment := range req.Comments {
 		if comment.CommitID != "" {
 			if payload.CommitID == "" {

vcs/types.go

@@ -48,6 +48,12 @@ type ReviewRequest struct {
 	// Event is the review verdict.
 	Event ReviewEvent
 
+	// CommitID is the commit SHA that this review targets.
+	// When non-empty, the review is anchored to this commit.
+	// For GitHub, this is passed as commit_id in the review request.
+	// For Gitea, this is passed as the commitID parameter to PostReview.
+	CommitID string
+
 	// Comments are optional inline file-level comments.
 	Comments []ReviewComment
 }