name: PR Checklist Validation (History Rewrite)

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

jobs:
  validate:
    name: Validate history-rewrite checklist (conditional)
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Validate PR checklist (only for history-rewrite changes)
        uses: actions/github-script@v7
        with:
          script: |
            const owner = context.repo.owner;
            const repo = context.repo.repo;
            const prNumber = context.issue.number;
            const pr = await github.rest.pulls.get({owner, repo, pull_number: prNumber});
            const body = (pr.data && pr.data.body) || '';

            // Determine if this PR modifies history-rewrite related files
            const filesResp = await github.rest.pulls.listFiles({ owner, repo, pull_number: prNumber });
            const files = filesResp.data.map(f => f.filename.toLowerCase());
            const relevant = files.some(fn => fn.startsWith('scripts/history-rewrite/') || fn.startsWith('docs/plans/history_rewrite.md') || fn.includes('history-rewrite'));
            if (!relevant) {
              core.info('No history-rewrite related files changed; skipping checklist validation.');
              return;
            }

            const required = [ 'preview_removals.sh', 'data/backups', "i will not run the destructive --force" ];
            const missing = required.filter(r => !body.toLowerCase().includes(r.toLowerCase()));
            if (missing.length > 0) {
              // Post a comment to the PR with instructions for filling the checklist
              const commentBody = `Hi! This PR touches history-rewrite artifacts and requires the checklist in .github/PULL_REQUEST_TEMPLATE/history-rewrite.md. The following items are missing in your PR body: ${missing.join(', ')}\n\nPlease update the PR description using the history-rewrite template and re-run checks.`;
              await github.rest.issues.createComment({ owner, repo, issue_number: prNumber, body: commentBody });
              core.setFailed('Missing required checklist items: ' + missing.join(', '));
            }