chore: import upstream snapshot with attribution

cmd/gortex/git.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"bytes"
+	"os/exec"
+	"strings"
+
+	"github.com/zzet/gortex/internal/churn"
+	"github.com/zzet/gortex/internal/indexer"
+)
+
+// gitCommitHash returns the HEAD commit hash for the repository at dir,
+// or an empty string if git is unavailable or the directory is not a repo.
+func gitCommitHash(dir string) string {
+	cmd := exec.Command("git", "rev-parse", "HEAD")
+	cmd.Dir = dir
+	var out bytes.Buffer
+	cmd.Stdout = &out
+	cmd.Stderr = nil
+	if err := cmd.Run(); err != nil {
+		return ""
+	}
+	return strings.TrimSpace(out.String())
+}
+
+// gitBranch returns the current branch name for the repository at dir.
+// It returns an empty string when git is unavailable, the directory is
+// not a repo, or HEAD is detached — callers then key snapshots by
+// commit hash instead of branch.
+func gitBranch(dir string) string {
+	cmd := exec.Command("git", "rev-parse", "--abbrev-ref", "HEAD")
+	cmd.Dir = dir
+	var out bytes.Buffer
+	cmd.Stdout = &out
+	cmd.Stderr = nil
+	if err := cmd.Run(); err != nil {
+		return ""
+	}
+	branch := strings.TrimSpace(out.String())
+	if branch == "HEAD" {
+		return "" // detached HEAD — no branch to key on
+	}
+	return branch
+}
+
+// canonicalRepo resolves a git worktree to the main repository it
+// shares a .git directory with, so every worktree of one repo keys its
+// index cache under a shared base — the per-branch snapshot slot then
+// gives each worktree its own entry. A non-worktree path is returned
+// unchanged.
+func canonicalRepo(dir string) string {
+	return indexer.ResolveWorktree(dir).MainRepoPath
+}
+
+// gitDefaultBranch returns the repository's default branch as a
+// rev-parseable reference. Thin wrapper over churn.DefaultBranch so
+// the CLI, daemon controller, and MCP tool resolve the same branch
+// the same way.
+func gitDefaultBranch(dir string) string {
+	return churn.DefaultBranch(dir)
+}
+