update-index.yml

name: Update snippets index
on:
  push:
    branches: [ main ]
  pull_request:
    types: [closed]
  # Allows manual triggering
  workflow_dispatch: 

# allow pushes
permissions:
  contents: write

jobs:
  generate-index:
    # Run on pushes or when a PR is merged — but skip runs triggered by the bot itself
    if: >
      (github.event_name == 'push' || (github.event_name == 'pull_request' && github.event.pull_request.merged == true))
      && github.actor != 'github-actions[bot]'
    runs-on: ubuntu-latest

    steps:
      - name: Checkout repository (full history & credentials)
        uses: actions/checkout@v4
        with:
          # Fetch depth 0 is crucial for proper rebase/merge history
          fetch-depth: 0 
          persist-credentials: true

      - name: Set up Python
        uses: actions/setup-python@v4
        with:
          python-version: '3.x'

      - name: Install requirements (if needed)
        run: |
          python -m pip install --upgrade pip
          # Install any minimal deps needed by tools/generate_index.py
          pip install PyGithub || true

      - name: Generate index
        run: python tools/generate_index.py

      - name: Commit and push index (Safe Rebase Strategy)
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -e
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

          # Only track the generated index file
          git add snippets/README.md

          # If nothing staged -> nothing to do
          if git diff --cached --quiet; then
            echo "No changes to commit"
            exit 0
          fi

          git commit -m "chore: update snippets index"

          # --- SAFE PUSH STRATEGY ---
          # 1. Pull remote changes and reapply the local commit on top (rebase).
          #    This is the simplest way to avoid non-fast-forward push rejections.
          echo "Syncing with remote main before push..."
          git pull origin main --rebase
          
          # 2. Push the result back to main.
          git push origin main