on:
  pull_request:
    types: [opened, synchronize, reopened]

jobs:
  lint:
    name: Lint YAML files
    runs-on: docker
    container:
      image: mafyuh/node-yamllint:v1.0.0
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Fetch all branches
        run: git fetch --all

      - name: Get modified YAML files
        id: get_changed_files
        run: |
          BASE_BRANCH=$(git merge-base HEAD origin/${{ github.event.pull_request.base.ref }})
          CHANGED_FILES=$(git diff --name-only $BASE_BRANCH HEAD | grep -E '\.(yml)$' || true)
          echo "CHANGED_FILES=$CHANGED_FILES" >> $GITHUB_ENV

      - name: Debug changed files
        run: echo "Changed files: ${{ env.CHANGED_FILES }}"

      - name: Run yamllint on modified files
        if: env.CHANGED_FILES != ''
        run: |
          yamllint $CHANGED_FILES
        env:
          CHANGED_FILES: ${{ env.CHANGED_FILES }}

      - name: Skip linting if no YAML files are changed
        if: env.CHANGED_FILES == ''
        run: echo "No YAML files changed in this PR. Skipping lint."