name: commit-validation
on: [ push ]

permissions:
  contents: read

jobs:
  check-commit-msg-length:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v6
    - name: Check commit message length
      id: check-commit-msg-length
      uses: actions/github-script@v8
      with:
        result-encoding: json
        script: |
          var longlines = 0;
          const commits = ${{ toJSON(github.event.commits) }};
          for (const commit of commits) {
            for (const line of commit.message.split('\n')) {
              if (line.length > 78) {
                 longlines += 1;
                 console.log("Overlong line:\n" + line);
              }
            }
          }
          return longlines
    - name: Get result
      run: |
        result=${{steps.check-commit-msg-length.outputs.result}}
        if [[ $result -eq 0 ]]; then
          echo "Ok"
          exit 0
        else
          echo "Commit messages contain $result lines longer than 78 characters."
          echo "See under 'Check commit message length' for a list of the lines."
          exit 1
        fi