name: Beads → GitHub Issue Sync

on:
  push:
    branches: [master]
    paths:
      - '.beads/**'
      - '.github/beads-snapshots/issues.jsonl'

# Serialize with forward-sync to prevent race conditions
concurrency:
  group: beads-sync
  cancel-in-progress: false

permissions:
  contents: read
  issues: write

jobs:
  reverse-sync:
    runs-on: ubuntu-latest
    steps:
      - name: Guard — skip loop commits
        env:
          COMMIT_MSG: ${{ github.event.head_commit.message }}
        run: |
          if [[ "$COMMIT_MSG" == chore\(beads\):* ]]; then
            echo "Loop guard: skipping chore(beads): commit"
            echo "SKIP=true" >> "$GITHUB_ENV"
          fi

      - name: Checkout current
        if: env.SKIP != 'true'
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v4
        with:
          fetch-depth: 0

      - name: Install Beads CLI (pinned to v1.0.0)
        if: env.SKIP != 'true'
        run: |
          BD_VERSION="1.0.0"
          BD_URL="https://github.com/steveyegge/beads/releases/download/v${BD_VERSION}/beads_${BD_VERSION}_linux_amd64.tar.gz"
          mkdir -p "$HOME/.local/bin"
          curl -fsSL "$BD_URL" | tar -xz -C "$HOME/.local/bin" bd
          chmod +x "$HOME/.local/bin/bd"
          echo "$HOME/.local/bin" >> "$GITHUB_PATH"

      - name: Detect and close
        if: env.SKIP != 'true'
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          BEFORE_SHA: ${{ github.event.before }}
        run: |
          OLD_SNAPSHOT_PATH="$RUNNER_TEMP/old-issues.jsonl"
          NEW_SNAPSHOT_PATH="$RUNNER_TEMP/new-issues.jsonl"
          BEFORE_WORKTREE="$RUNNER_TEMP/beads-before"

          generate_snapshot() {
            local repo_root="$1"
            local output_path="$2"

            BEADS_DIR="$repo_root/.beads" bd init 2>/dev/null || true
            if BEADS_DIR="$repo_root/.beads" bd backup --force 2>/dev/null; then
              cp "$repo_root/.beads/backup/issues.jsonl" "$output_path"
            else
              : > "$output_path"
            fi
          }

          # Rebuild the current snapshot from the pushed Beads state so local bd close
          # transitions are reflected even when the tracked snapshot file was not updated.
          generate_snapshot "$GITHUB_WORKSPACE" "$NEW_SNAPSHOT_PATH"

          # Use github.event.before (pre-push SHA) to catch multi-commit pushes.
          # Rebuild the previous snapshot from that tree's Beads state when possible.
          if [ "$BEFORE_SHA" = "0000000000000000000000000000000000000000" ] || [ -z "$BEFORE_SHA" ]; then
            : > "$OLD_SNAPSHOT_PATH"
          elif git cat-file -e "$BEFORE_SHA:.beads" 2>/dev/null; then
            rm -rf "$BEFORE_WORKTREE"
            mkdir -p "$BEFORE_WORKTREE"
            git archive "$BEFORE_SHA" .beads | tar -x -C "$BEFORE_WORKTREE"
            generate_snapshot "$BEFORE_WORKTREE" "$OLD_SNAPSHOT_PATH"
          else
            # Fallback for historical commits that predate tracked .beads state.
            OLD_CONTENT=$(git show "$BEFORE_SHA":.github/beads-snapshots/issues.jsonl 2>/dev/null || echo "")
            printf '%s' "$OLD_CONTENT" > "$OLD_SNAPSHOT_PATH"
          fi

          node scripts/github-beads-sync/reverse-sync-cli.mjs "$OLD_SNAPSHOT_PATH" "$NEW_SNAPSHOT_PATH"