Initial commit

Co-Authored-By: Claude <noreply@anthropic.com>

internal/git/git.go

@@ -0,0 +1,100 @@
+package git
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	gogit "github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/transport"
+	"github.com/go-git/go-git/v5/plumbing/transport/http"
+)
+
+// Service handles Git operations for projects.
+type Service struct{}
+
+// New creates a new Git Service.
+func New() *Service {
+	return &Service{}
+}
+
+// CloneOrPull clones a repo if it doesn't exist locally, or pulls latest changes.
+// Returns the commit hash of HEAD after the operation.
+func (s *Service) CloneOrPull(url, branch, username, password, dstDir string) (string, error) {
+	// Check if repo already exists
+	repo, err := gogit.PlainOpen(dstDir)
+	if err == nil {
+		// Repo exists, pull
+		return s.pull(repo, branch, username, password)
+	}
+
+	// Clone fresh
+	return s.clone(url, branch, username, password, dstDir)
+}
+
+func (s *Service) clone(url, branch, username, password, dstDir string) (string, error) {
+	// Ensure parent directory exists
+	os.MkdirAll(filepath.Dir(dstDir), 0755)
+	// Remove target if it exists (shouldn't, but be safe)
+	os.RemoveAll(dstDir)
+
+	var auth transport.AuthMethod
+	if username != "" || password != "" {
+		auth = &http.BasicAuth{
+			Username: username,
+			Password: password,
+		}
+	}
+
+	refName := plumbing.NewBranchReferenceName(branch)
+	repo, err := gogit.PlainClone(dstDir, false, &gogit.CloneOptions{
+		URL:           url,
+		Auth:          auth,
+		ReferenceName: refName,
+		SingleBranch:  true,
+		Depth:         1,
+		Progress:      nil,
+	})
+	if err != nil {
+		return "", fmt.Errorf("clone failed: %w", err)
+	}
+
+	return getHeadHash(repo)
+}
+
+func (s *Service) pull(repo *gogit.Repository, branch, username, password string) (string, error) {
+	w, err := repo.Worktree()
+	if err != nil {
+		return "", fmt.Errorf("worktree: %w", err)
+	}
+
+	var auth transport.AuthMethod
+	if username != "" || password != "" {
+		auth = &http.BasicAuth{
+			Username: username,
+			Password: password,
+		}
+	}
+
+	refName := plumbing.NewBranchReferenceName(branch)
+	err = w.Pull(&gogit.PullOptions{
+		RemoteName:    "origin",
+		Auth:          auth,
+		ReferenceName: refName,
+		SingleBranch:  true,
+	})
+	if err != nil && err != gogit.NoErrAlreadyUpToDate {
+		return "", fmt.Errorf("pull failed: %w", err)
+	}
+
+	return getHeadHash(repo)
+}
+
+func getHeadHash(repo *gogit.Repository) (string, error) {
+	ref, err := repo.Head()
+	if err != nil {
+		return "", err
+	}
+	return ref.Hash().String(), nil
+}