name: PR Conventional Labeler

# Labels each PR with its conventional-commit type (feat, fix, docs, perf,
# refactor, chore) derived from the PR title. These labels drive the changelog
# categories in .github/release.yml when release-please generates notes.
# chore is labeled but excluded from the changelog (see .github/release.yml),
# preserving the previous "chore hidden" behavior.

on:
  pull_request_target:
    types: [opened, edited, reopened, ready_for_review]

permissions:
  contents: read
  pull-requests: write

jobs:
  label:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v7
        with:
          script: |
            // Conventional-commit types we manage as labels.
            const managedLabels = ['feat', 'fix', 'docs', 'perf', 'refactor', 'chore'];

            const pr = context.payload.pull_request;
            const title = pr.title || '';

            // Matches: feat:, fix(scope):, perf!:, refactor(api)!: ...
            const match = title.match(/^([a-zA-Z]+)(\([^)]*\))?!?:/);
            const type = match ? match[1].toLowerCase() : null;
            const target = managedLabels.includes(type) ? type : null;

            const { owner, repo } = context.repo;
            const issue_number = pr.number;
            const current = pr.labels.map(l => l.name);

            // Remove any managed label that no longer matches the title
            // (e.g. PR retitled from feat: to fix:).
            for (const label of current) {
              if (managedLabels.includes(label) && label !== target) {
                await github.rest.issues
                  .removeLabel({ owner, repo, issue_number, name: label })
                  .catch(() => {});
              }
            }

            // Apply the matching label if not already present.
            if (target && !current.includes(target)) {
              await github.rest.issues.addLabels({
                owner, repo, issue_number, labels: [target],
              });
            }