name: Comment PR Artifacts

on:
  workflow_run:
    workflows:
      - PR Build Validation
    types:
      - completed

permissions:
  actions: read
  pull-requests: write
  issues: write

jobs:
  comment:
    # Only runs for PR Build Validation runs triggered by PRs.
    if: ${{ github.event.workflow_run.event == 'pull_request' }}
    runs-on: ubuntu-latest
    steps:
      - name: Comment with artifact download link
        uses: actions/github-script@v7
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const run = context.payload.workflow_run;
            const owner = context.repo.owner;
            const repo = context.repo.repo;

            const prs = run.pull_requests || [];
            const prNumber = prs[0]?.number;
            if (!prNumber) {
              core.info('No PR number found for this workflow_run; skipping.');
              return;
            }

            // Only comment when the PR build job actually ran (i.e. authorization passed).
            // Unauthorized PRs targeting non-dev will skip the `build` job.
            const jobs = await github.paginate(
              github.rest.actions.listJobsForWorkflowRun,
              { owner, repo, run_id: run.id, per_page: 100 }
            );
            const buildJob = jobs.find((j) => j.name === 'build');
            if (!buildJob) {
              core.info('No `build` job found on this run; skipping.');
              return;
            }
            if (buildJob.conclusion === 'skipped') {
              core.info('`build` job was skipped; skipping comment.');
              return;
            }

            // List artifacts from the run. If none exist (e.g. build failed before packaging),
            // still comment with the run link so testers can see logs.
            const artifacts = await github.paginate(
              github.rest.actions.listWorkflowRunArtifacts,
              { owner, repo, run_id: run.id, per_page: 100 }
            );
            const active = artifacts.filter((a) => !a.expired);

            const marker = '<!-- codenomad-pr-artifacts -->';
            const runUrl = `https://github.com/${owner}/${repo}/actions/runs/${run.id}`;
            const retentionDays = 7;

            const artifactsBlock = active.length
              ? ['Artifacts:', ...active.map((a) => `- ${a.name}`)].join('\n')
              : 'Artifacts: (none found on this run)';

            const body = [
              marker,
              'PR builds are available as GitHub Actions artifacts:',
              '',
              runUrl,
              '',
              `Artifacts expire in ${retentionDays} days.`,
              artifactsBlock,
            ].join('\n');

            const comments = await github.paginate(
              github.rest.issues.listComments,
              { owner, repo, issue_number: prNumber, per_page: 100 }
            );
            const existing = comments.find((c) => (c.body || '').includes(marker));

            if (existing) {
              await github.rest.issues.updateComment({
                owner,
                repo,
                comment_id: existing.id,
                body,
              });
              core.info(`Updated existing artifacts comment: ${existing.html_url}`);
            } else {
              const created = await github.rest.issues.createComment({
                owner,
                repo,
                issue_number: prNumber,
                body,
              });
              core.info(`Created artifacts comment: ${created.data.html_url}`);
            }