name: Fix linting, formatting, and Bazel module lock file

on:
  push:
    branches:
      - 'master'

permissions:
  contents: write

jobs:
  auto-format:
    name: Auto-format on push
    runs-on: ubuntu-latest
    if: github.repository_owner == 'The-OpenROAD-Project'
    env:
      BUILDIFIER_VERSION: v8.2.1

    steps:
      - name: Checkout
        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
        with:
          fetch-depth: 0

      - name: Install Python tools
        run: |
          python3 -m venv venv
          venv/bin/pip install tclint==0.7.0 black

      - name: Cache buildifier
        id: cache-buildifier
        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9  # v6.1.0
        with:
          path: ./buildifier
          key: ${{ runner.os }}-buildifier-${{ env.BUILDIFIER_VERSION }}

      - name: Download buildifier
        if: steps.cache-buildifier.outputs.cache-hit != 'true'
        run: |
          wget https://github.com/bazelbuild/buildtools/releases/download/${BUILDIFIER_VERSION}/buildifier-linux-amd64 -O buildifier
          chmod +x buildifier

      - name: Auto-format
        run: |
          # Skip if the last commit was already an auto-format
          if git log -1 --format='%s' | grep -qF 'ci: auto-format'; then
            exit 0
          fi

          # Get files changed in the full pushed range.
          changed=$(git diff --name-only "${{ github.event.before }}..${{ github.sha }}")

          # Run clang-format, excluding upstream-managed directories
          echo "$changed" \
            | grep -E '\.(h|hh|hpp|hxx|c|cc|cpp|cxx)$' \
            | grep -v '^src/sta/' \
            | grep -v '^src/odb/src/codeGenerator/' \
            | xargs --no-run-if-empty clang-format -i

          # Run black on changed Python files
          source venv/bin/activate
          echo "$changed" \
            | grep -E '\.py$' \
            | xargs --no-run-if-empty black

          # Run buildifier on changed Bazel files
          echo "$changed" \
            | grep -E '(BUILD|WORKSPACE|\.bzl|\.bazel)$' \
            | xargs --no-run-if-empty ./buildifier -lint=fix

          # Run tclfmt on changed Tcl files
          echo "$changed" \
            | grep -E '\.tcl$' \
            | grep -v '^src/sta/' \
            | xargs --no-run-if-empty tclfmt --in-place

          # Commit if any diffs were created
          if [ -n "$(git diff --name-only)" ]; then
            git config user.name "github-actions[bot]"
            git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
            git diff --name-only | xargs git add --
            git commit -m "ci: auto-format [skip ci]"
            git push
            echo "Auto-format committed fixes and pushed."
          fi