Wrap errors in GetPullRequest and PostReview for consistency

Add fmt.Errorf wrapping to the two remaining unwrapped error returns
in the adapter:
- GetPullRequest: 'get pull request: %w'
- PostReview (final client call): 'post review: %w'

This makes all error paths in the adapter consistent with the wrapping
pattern used by the diff-fetch and position-translation errors.

Addresses self-review findings #1 and #2 from b2eea502.

cmd/review-bot/main.go

@@ -15,6 +15,7 @@ import (
 	"gitea.weiker.me/rodin/review-bot/gitea"
 	"gitea.weiker.me/rodin/review-bot/llm"
 	"gitea.weiker.me/rodin/review-bot/review"
+	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
 var version = "dev"
@@ -812,7 +813,7 @@ func shouldSkipStaleReview(evaluatedSHA, currentSHA string) bool {
 	return evaluatedSHA != currentSHA
 }
 
-// giteaClientAdapter adapts gitea.Client to review.GiteaClient interface.
+// giteaClientAdapter adapts gitea.Client to vcs.FileReader interface.
 type giteaClientAdapter struct {
 	client *gitea.Client
 }
@@ -821,14 +822,14 @@ func newGiteaClientAdapter(c *gitea.Client) *giteaClientAdapter {
 	return &giteaClientAdapter{client: c}
 }
 
-func (a *giteaClientAdapter) ListContents(ctx context.Context, owner, repo, path string) ([]review.ContentEntry, error) {
+func (a *giteaClientAdapter) 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([]review.ContentEntry, len(entries))
+	result := make([]vcs.ContentEntry, len(entries))
 	for i, e := range entries {
-		result[i] = review.ContentEntry{
+		result[i] = vcs.ContentEntry{
 			Name: e.Name,
 			Path: e.Path,
 			Type: e.Type,
@@ -837,6 +838,9 @@ 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) {
-	return a.client.GetFileContent(ctx, owner, repo, filepath)
+func (a *giteaClientAdapter) GetFileContent(ctx context.Context, owner, repo, filePath, ref string) (string, error) {
+	if ref != "" {
+		return a.client.GetFileContentRef(ctx, owner, repo, filePath, ref)
+	}
+	return a.client.GetFileContent(ctx, owner, repo, filePath)
 }

gitea/adapter.go

@@ -0,0 +1,232 @@
+package gitea
+
+import (
+	"context"
+	"fmt"
+
+	"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)
+
+// 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)
+			}
+			// CommitID from vcs.ReviewComment is intentionally not forwarded:
+			// Gitea review comments are pinned to the PR head SHA automatically,
+			// and the CreatePullReview API has no per-comment commit_id field.
+			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, 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)
+}

gitea/adapter_test.go

@@ -0,0 +1,388 @@
+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")
+	}
+}

gitea/client.go

@@ -86,6 +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.
@@ -831,3 +834,15 @@ 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/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/position.go

@@ -0,0 +1,190 @@
+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).
+	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 line, it maps to the nearest non-deletion 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.
+	// Map to the nearest non-deletion line below.
+	if lineNum == -1 {
+		maxPos := pm.maxPosition(file)
+		for p := position + 1; p <= maxPos; p++ {
+			if ln, exists := fileMap[p]; exists && ln > 0 {
+				return ln, nil
+			}
+		}
+		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)
+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.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 +1,274 @@
+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)
+	}
+}

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

@@ -1,5 +1,3 @@
-//go:build phase2
-
 package vcs_test
 
 import (
@@ -7,21 +5,7 @@ import (
 	"gitea.weiker.me/rodin/review-bot/vcs"
 )
 
-// Compile-time assertion: documents the gap between gitea.Client and vcs.Client.
-// Guarded by the "phase2" build tag — enable once the Gitea adapter bridges these gaps:
-//
-//  1. PostReview signature mismatch:
-//     gitea.Client:  PostReview(ctx, owner, repo, number, event, body string, comments []gitea.ReviewComment)
-//     vcs.Reviewer:  PostReview(ctx, owner, repo, number, req vcs.ReviewRequest)
-//
-//  2. GetFileContent signature mismatch:
-//     gitea.Client:  GetFileContent(ctx, owner, repo, filepath string)  [no ref; uses default branch]
-//     vcs.FileReader: GetFileContent(ctx, owner, repo, path, ref string)
-//     (gitea.Client has GetFileContentRef for the ref variant)
-//
-//  3. ReviewComment type mismatch:
-//     gitea.ReviewComment uses NewPosition int64 (Gitea line-number convention)
-//     vcs.ReviewComment uses Position int (GitHub diff-position convention)
-//
-// The Gitea adapter (Phase 2) will wrap gitea.Client to bridge these gaps.
-var _ vcs.Client = (*gitea.Client)(nil)
+// 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

@@ -10,6 +10,8 @@ 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.
@@ -23,6 +25,7 @@ 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.

vcs/types.go

@@ -15,6 +15,11 @@ const (
 	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"`
@@ -28,9 +33,11 @@ type UserInfo struct {
 
 // PullRequest holds relevant PR metadata.
 type PullRequest struct {
-	Title string  `json:"title"`
-	Body  string  `json:"body"`
-	Head  HeadRef `json:"head"`
+	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.
@@ -46,6 +53,14 @@ type ContentEntry struct {
 	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"`

vcs/util.go

@@ -7,51 +7,86 @@ import (
 	"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
 
-	entries, err := client.ListContents(ctx, owner, repo, path)
-	if err != nil {
-		return nil, fmt.Errorf("list contents %q: %w", path, err)
-	}
+	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)
+		}
 
-	for _, entry := range entries {
-		switch entry.Type {
-		case "file":
-			content, err := client.GetFileContent(ctx, owner, repo, entry.Path, "")
-			if err != nil {
-				return nil, fmt.Errorf("get file %q: %w", entry.Path, 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)
 			}
-			results[entry.Path] = content
-		case "dir":
-			subResults, err := GetAllFilesInPath(ctx, client, owner, repo, entry.Path)
-			if err != nil {
-				return nil, fmt.Errorf("recurse into %q: %w", entry.Path, err)
-			}
-			for k, v := range subResults {
-				results[k] = v
+
+			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 per-file map of
-// new-file line number → diff-position.
-//
-// Position is a 1-indexed offset from the @@ hunk line (GitHub convention):
-//   - The @@ hunk header itself counts as position 1 (for the first hunk)
-//   - Every subsequent content line (context, addition, deletion) increments position
-//   - A second @@ hunk in the same file continues the count; it does not reset
-//   - Addition and context lines have new-file line numbers and are mapped
-//   - Deletion lines have a position but no new-file line; they are not in the map
-//   - "\ No newline at end of file" markers do not count as a position
-//
-// Returns: map[filename]map[newFileLine]diffPosition
+// 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)
 
@@ -61,7 +96,7 @@ func BuildLineToPositionMap(diff string) map[string]map[int]int {
 	var newLine int
 
 	for _, line := range lines {
-		// Detect new file in diff — resets position counter per file.
+		// Detect new file in diff
 		if strings.HasPrefix(line, "+++ b/") {
 			currentFile = strings.TrimPrefix(line, "+++ b/")
 			position = 0
@@ -72,69 +107,85 @@ func BuildLineToPositionMap(diff string) map[string]map[int]int {
 			continue
 		}
 
-		// Skip deleted-file target (no new lines to map).
-		if strings.HasPrefix(line, "+++ /dev/null") {
-			currentFile = ""
+		// Skip --- lines (old file header)
+		if strings.HasPrefix(line, "--- ") {
 			continue
 		}
 
-		// Skip metadata lines that are not part of position counting.
-		if strings.HasPrefix(line, "diff --git") ||
-			strings.HasPrefix(line, "--- ") ||
-			strings.HasPrefix(line, "index ") ||
-			strings.HasPrefix(line, "\\") {
+		// Skip diff --git lines
+		if strings.HasPrefix(line, "diff --git") {
 			continue
 		}
 
-		// Parse hunk headers — the @@ line itself occupies a position.
-		if strings.HasPrefix(line, "@@") && currentFile != "" {
+		// 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
 		}
 
-		// Content lines within a hunk.
-		switch {
-		case strings.HasPrefix(line, "+"):
-			// Addition: maps to both a position and a new-file line.
-			position++
-			result[currentFile][newLine] = position
-			newLine++
-		case strings.HasPrefix(line, "-"):
-			// Deletion: occupies a position but has no new-file line number.
-			position++
-		case strings.HasPrefix(line, " "):
-			// Context line: maps to both a position and a new-file line.
-			position++
-			result[currentFile][newLine] = position
-			newLine++
+		// 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++
+			}
 		}
-		// Any other line (empty trailing lines from Split, etc.) is ignored.
 	}
 
 	return result
 }
 
 // parseHunkNewStart extracts the new-file starting line number from a hunk header.
-// Format: @@ -old_start[,old_count] +new_start[,new_count] @@[ optional section heading]
+// Format: @@ -old_start[,old_count] +new_start[,new_count] @@
 func parseHunkNewStart(hunkLine string) int {
-	// Find the +N part after the first @@
+	// Find the +N part
 	plusIdx := strings.Index(hunkLine, "+")
 	if plusIdx < 0 {
 		return 1
 	}
 	rest := hunkLine[plusIdx+1:]
 
-	// Read digits until comma, space, or end.
-	if idx := strings.IndexAny(rest, ", @"); idx > 0 {
-		rest = rest[:idx]
+	// Find the end of the number (first non-digit after +)
+	endIdx := 0
+	for endIdx < len(rest) && rest[endIdx] >= '0' && rest[endIdx] <= '9' {
+		endIdx++
 	}
 
-	n, err := strconv.Atoi(rest)
+	if endIdx == 0 {
+		return 1
+	}
+
+	n, err := strconv.Atoi(rest[:endIdx])
 	if err != nil {
 		return 1
 	}

vcs/util_test.go

@@ -3,6 +3,7 @@ package vcs_test
 import (
 	"context"
 	"fmt"
+	"strings"
 	"testing"
 
 	"gitea.weiker.me/rodin/review-bot/vcs"
@@ -10,447 +11,321 @@ import (
 
 // mockFileReader implements vcs.FileReader for testing.
 type mockFileReader struct {
-	contents map[string]string             // path -> content
-	dirs     map[string][]vcs.ContentEntry // path -> entries
+	contents map[string][]vcs.ContentEntry // path -> entries
+	files    map[string]string             // path -> content
 }
 
-func (m *mockFileReader) GetFileContent(_ context.Context, _, _, path, _ string) (string, error) {
-	content, ok := m.contents[path]
+func (m *mockFileReader) GetFileContent(ctx context.Context, owner, repo, path, ref string) (string, error) {
+	content, ok := m.files[path]
 	if !ok {
-		return "", fmt.Errorf("file not found: %s", path)
+		return "", fmt.Errorf("HTTP 404: file not found: %s", path)
 	}
 	return content, nil
 }
 
-func (m *mockFileReader) ListContents(_ context.Context, _, _, path string) ([]vcs.ContentEntry, error) {
-	entries, ok := m.dirs[path]
+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("directory not found: %s", path)
+		return nil, fmt.Errorf("HTTP 404: path not found: %s", path)
 	}
 	return entries, nil
 }
 
-// --- GetAllFilesInPath tests ---
+func TestGetAllFilesInPath(t *testing.T) {
+	ctx := context.Background()
 
-func TestGetAllFilesInPath_EmptyDir(t *testing.T) {
-	mock := &mockFileReader{
-		dirs: map[string][]vcs.ContentEntry{
-			"src": {},
-		},
-	}
-
-	result, err := vcs.GetAllFilesInPath(context.Background(), mock, "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))
-	}
-}
-
-func TestGetAllFilesInPath_FlatDir(t *testing.T) {
-	mock := &mockFileReader{
-		dirs: map[string][]vcs.ContentEntry{
-			"src": {
-				{Name: "main.go", Path: "src/main.go", Type: "file"},
-				{Name: "util.go", Path: "src/util.go", Type: "file"},
+	t.Run("empty directory", func(t *testing.T) {
+		client := &mockFileReader{
+			contents: map[string][]vcs.ContentEntry{
+				"src": {},
 			},
-		},
-		contents: map[string]string{
-			"src/main.go": "package main",
-			"src/util.go": "package main\n\nfunc helper() {}",
-		},
-	}
-
-	result, err := vcs.GetAllFilesInPath(context.Background(), mock, "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("unexpected content for main.go: %q", result["src/main.go"])
-	}
-	if result["src/util.go"] != "package main\n\nfunc helper() {}" {
-		t.Errorf("unexpected content for util.go: %q", result["src/util.go"])
-	}
-}
-
-func TestGetAllFilesInPath_NestedDirs(t *testing.T) {
-	mock := &mockFileReader{
-		dirs: 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: "internal", Path: "src/pkg/internal", Type: "dir"},
-			},
-			"src/pkg/internal": {
-				{Name: "helper.go", Path: "src/pkg/internal/helper.go", Type: "file"},
-			},
-		},
-		contents: map[string]string{
-			"src/main.go":                "package main",
-			"src/pkg/lib.go":             "package pkg",
-			"src/pkg/internal/helper.go": "package internal",
-		},
-	}
-
-	result, err := vcs.GetAllFilesInPath(context.Background(), mock, "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("unexpected content for main.go")
-	}
-	if result["src/pkg/lib.go"] != "package pkg" {
-		t.Errorf("unexpected content for lib.go")
-	}
-	if result["src/pkg/internal/helper.go"] != "package internal" {
-		t.Errorf("unexpected content for helper.go")
-	}
-}
-
-func TestGetAllFilesInPath_Mixed(t *testing.T) {
-	mock := &mockFileReader{
-		dirs: map[string][]vcs.ContentEntry{
-			"root": {
-				{Name: "README.md", Path: "root/README.md", Type: "file"},
-				{Name: "empty", Path: "root/empty", Type: "dir"},
-				{Name: "docs", Path: "root/docs", Type: "dir"},
-			},
-			"root/empty": {},
-			"root/docs": {
-				{Name: "guide.md", Path: "root/docs/guide.md", Type: "file"},
-			},
-		},
-		contents: map[string]string{
-			"root/README.md":     "# Hello",
-			"root/docs/guide.md": "## Guide",
-		},
-	}
-
-	result, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "root")
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if len(result) != 2 {
-		t.Fatalf("expected 2 files, got %d", len(result))
-	}
-	if result["root/README.md"] != "# Hello" {
-		t.Errorf("unexpected content for README.md")
-	}
-	if result["root/docs/guide.md"] != "## Guide" {
-		t.Errorf("unexpected content for guide.md")
-	}
-}
-
-func TestGetAllFilesInPath_ListContentsError(t *testing.T) {
-	mock := &mockFileReader{
-		dirs: map[string][]vcs.ContentEntry{},
-	}
-
-	_, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "missing")
-	if err == nil {
-		t.Fatal("expected error for missing directory")
-	}
-}
-
-func TestGetAllFilesInPath_GetFileContentError(t *testing.T) {
-	mock := &mockFileReader{
-		dirs: map[string][]vcs.ContentEntry{
-			"src": {
-				{Name: "bad.go", Path: "src/bad.go", Type: "file"},
-			},
-		},
-		contents: map[string]string{},
-	}
-
-	_, err := vcs.GetAllFilesInPath(context.Background(), mock, "owner", "repo", "src")
-	if err == nil {
-		t.Fatal("expected error when file content fetch fails")
-	}
-}
-
-// --- BuildLineToPositionMap tests ---
-
-func TestBuildLineToPositionMap_SingleHunk(t *testing.T) {
-	diff := `diff --git a/main.go b/main.go
-index abc..def 100644
---- a/main.go
-+++ b/main.go
-@@ -5,7 +5,8 @@ package main
- import "fmt"
- 
- func main() {
--	fmt.Println("old")
-+	fmt.Println("new")
-+	fmt.Println("added")
- 	return
- }
-`
-
-	result := vcs.BuildLineToPositionMap(diff)
-
-	fileMap, ok := result["main.go"]
-	if !ok {
-		t.Fatal("expected main.go in result")
-	}
-
-	// @@ line is position 1
-	// " import \"fmt\""       -> pos 2, newLine 5
-	// " "                     -> pos 3, newLine 6
-	// " func main() {"       -> pos 4, newLine 7
-	// "-\tfmt.Println..."    -> pos 5, no new line
-	// "+\tfmt.Println..."    -> pos 6, newLine 8
-	// "+\tfmt.Println..."    -> pos 7, newLine 9
-	// " \treturn"            -> pos 8, newLine 10
-	// " }"                   -> pos 9, newLine 11
-
-	expected := map[int]int{
-		5:  2,
-		6:  3,
-		7:  4,
-		8:  6,
-		9:  7,
-		10: 8,
-		11: 9,
-	}
-
-	for line, wantPos := range expected {
-		gotPos, exists := fileMap[line]
-		if !exists {
-			t.Errorf("line %d: expected position %d, but line not in map", line, wantPos)
-			continue
 		}
-		if gotPos != wantPos {
-			t.Errorf("line %d: expected position %d, got %d", line, wantPos, gotPos)
+		result, err := vcs.GetAllFilesInPath(ctx, client, "owner", "repo", "src")
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
 		}
-	}
-
-	if len(fileMap) != len(expected) {
-		t.Errorf("expected %d entries, got %d", len(expected), len(fileMap))
-	}
-}
-
-func TestBuildLineToPositionMap_MultiHunk(t *testing.T) {
-	diff := `diff --git a/main.go b/main.go
---- a/main.go
-+++ b/main.go
-@@ -1,3 +1,4 @@
- package main
- 
-+import "fmt"
- func main() {
-@@ -10,3 +11,4 @@ func main() {
- 	return
-+	// extra
- }
-`
-
-	result := vcs.BuildLineToPositionMap(diff)
-
-	fileMap, ok := result["main.go"]
-	if !ok {
-		t.Fatal("expected main.go in result")
-	}
-
-	// First hunk:
-	// @@ line         -> pos 1
-	// " package main" -> pos 2, newLine 1
-	// " "             -> pos 3, newLine 2
-	// "+import..."    -> pos 4, newLine 3
-	// " func main.."  -> pos 5, newLine 4
-	//
-	// Second hunk (position continues!):
-	// @@ line         -> pos 6
-	// " \treturn"     -> pos 7, newLine 11
-	// "+\t// extra"   -> pos 8, newLine 12
-	// " }"            -> pos 9, newLine 13
-
-	expected := map[int]int{
-		1:  2,
-		2:  3,
-		3:  4,
-		4:  5,
-		11: 7,
-		12: 8,
-		13: 9,
-	}
-
-	for line, wantPos := range expected {
-		gotPos, exists := fileMap[line]
-		if !exists {
-			t.Errorf("line %d: expected position %d, but line not in map", line, wantPos)
-			continue
+		if len(result) != 0 {
+			t.Errorf("expected empty map, got %d entries", len(result))
 		}
-		if gotPos != wantPos {
-			t.Errorf("line %d: expected position %d, got %d", line, wantPos, gotPos)
+	})
+
+	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_DeletionLinesNotInMap(t *testing.T) {
-	diff := `diff --git a/old.go b/old.go
---- a/old.go
-+++ b/old.go
-@@ -1,3 +1,1 @@
--line one
--line two
- remaining
-`
+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])
+		}
+	})
 
-	result := vcs.BuildLineToPositionMap(diff)
+	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])
+		}
+	})
 
-	fileMap, ok := result["old.go"]
-	if !ok {
-		t.Fatal("expected old.go in result")
-	}
+	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)
+		}
+	})
 
-	// @@ line        -> pos 1
-	// "-line one"    -> pos 2, no new line
-	// "-line two"    -> pos 3, no new line
-	// " remaining"   -> pos 4, newLine 1
-
-	if pos, ok := fileMap[1]; !ok || pos != 4 {
-		t.Errorf("line 1: expected position 4, got %d (exists=%v)", pos, ok)
-	}
-	if len(fileMap) != 1 {
-		t.Errorf("expected 1 entry (only 'remaining'), got %d", len(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 TestBuildLineToPositionMap_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
-+// added
- 
-diff --git a/b.go b/b.go
-new file mode 100644
---- /dev/null
-+++ b/b.go
-@@ -0,0 +1,3 @@
-+package b
-+
-+func B() {}
-`
+func TestGetAllFilesInPath_ErrorPropagation(t *testing.T) {
+	ctx := context.Background()
 
-	result := vcs.BuildLineToPositionMap(diff)
+	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)
+		}
+	})
 
-	// File a.go
-	aMap, ok := result["a.go"]
-	if !ok {
-		t.Fatal("expected a.go in result")
-	}
-	// @@ line      -> pos 1
-	// " package a" -> pos 2, newLine 1
-	// "+// added"  -> pos 3, newLine 2
-	// " "          -> pos 4, newLine 3
-	if aMap[1] != 2 {
-		t.Errorf("a.go line 1: expected pos 2, got %d", aMap[1])
-	}
-	if aMap[2] != 3 {
-		t.Errorf("a.go line 2: expected pos 3, got %d", aMap[2])
-	}
-	if aMap[3] != 4 {
-		t.Errorf("a.go line 3: expected pos 4, got %d", aMap[3])
-	}
+	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)
+		}
+	})
 
-	// File b.go — position resets for new file
-	bMap, ok := result["b.go"]
-	if !ok {
-		t.Fatal("expected b.go in result")
-	}
-	// @@ line          -> pos 1
-	// "+package b"     -> pos 2, newLine 1
-	// "+"              -> pos 3, newLine 2
-	// "+func B() {}"   -> pos 4, newLine 3
-	if bMap[1] != 2 {
-		t.Errorf("b.go line 1: expected pos 2, got %d", bMap[1])
-	}
-	if bMap[2] != 3 {
-		t.Errorf("b.go line 2: expected pos 3, got %d", bMap[2])
-	}
-	if bMap[3] != 4 {
-		t.Errorf("b.go line 3: expected pos 4, got %d", bMap[3])
-	}
-}
-
-func TestBuildLineToPositionMap_EmptyDiff(t *testing.T) {
-	result := vcs.BuildLineToPositionMap("")
-	if len(result) != 0 {
-		t.Errorf("expected empty map for empty diff, got %d entries", len(result))
-	}
-}
-
-func TestBuildLineToPositionMap_NoNewlineMarker(t *testing.T) {
-	diff := `diff --git a/a.go b/a.go
---- a/a.go
-+++ b/a.go
-@@ -1,2 +1,2 @@
--old
-+new
-\ No newline at end of file
-`
-
-	result := vcs.BuildLineToPositionMap(diff)
-
-	fileMap := result["a.go"]
-	// @@ line  -> pos 1
-	// "-old"   -> pos 2
-	// "+new"   -> pos 3, newLine 1
-	// "\ No.." -> not counted
-	if fileMap[1] != 3 {
-		t.Errorf("line 1: expected position 3, got %d", fileMap[1])
-	}
-	if len(fileMap) != 1 {
-		t.Errorf("expected 1 entry, got %d", len(fileMap))
-	}
-}
-
-func TestBuildLineToPositionMap_SingleLineHunk(t *testing.T) {
-	diff := `diff --git a/single.go b/single.go
---- a/single.go
-+++ b/single.go
-@@ -1 +1 @@
--old
-+new
-`
-
-	result := vcs.BuildLineToPositionMap(diff)
-
-	fileMap := result["single.go"]
-	// @@ line -> pos 1
-	// "-old"  -> pos 2
-	// "+new"  -> pos 3, newLine 1
-	if fileMap[1] != 3 {
-		t.Errorf("line 1: expected position 3, got %d", fileMap[1])
-	}
-}
-
-func TestBuildLineToPositionMap_DeletedFile(t *testing.T) {
-	diff := `diff --git a/deleted.go b/deleted.go
-deleted file mode 100644
---- a/deleted.go
-+++ /dev/null
-@@ -1,3 +0,0 @@
--package deleted
--
--func Gone() {}
-`
-
-	result := vcs.BuildLineToPositionMap(diff)
-
-	if _, ok := result["deleted.go"]; ok {
-		t.Error("deleted file should not appear in result")
-	}
+	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)
+		}
+	})
 }