pr-comment.yml

name: PR Comment

on:
  workflow_run:
    workflows: ["PR Build"]
    types: [completed]

permissions:
  pull-requests: write
  actions: read

jobs:
  comment:
    if: >-
      github.event.workflow_run.conclusion == 'success' &&
      github.event.workflow_run.event == 'pull_request'
    runs-on: ubuntu-latest
    steps:
      - name: Download binaries artifact
        uses: actions/download-artifact@v4
        with:
          name: uploadcare-cli-binaries
          path: binaries
          run-id: ${{ github.event.workflow_run.id }}
          github-token: ${{ secrets.GITHUB_TOKEN }}

      - name: Comment on PR
        uses: actions/github-script@v7
        with:
          script: |
            const fs = require('fs');

            const headSha = context.payload.workflow_run.head_sha;
            const headRepo = context.payload.workflow_run.head_repository;

            // Try workflow_run.pull_requests first (populated for same-repo PRs)
            let prNumber = context.payload.workflow_run.pull_requests?.[0]?.number;

            // For forked PRs, pull_requests is empty — look up by head owner:branch
            if (!prNumber) {
              const { data: pulls } = await github.rest.pulls.list({
                owner: context.repo.owner,
                repo: context.repo.repo,
                state: 'open',
                head: `${headRepo.owner.login}:${context.payload.workflow_run.head_branch}`,
              });
              if (pulls.length === 0) {
                core.warning(`No open PR found for ${headRepo.owner.login}:${context.payload.workflow_run.head_branch} — skipping comment`);
                return;
              }
              prNumber = pulls[0].number;
            }

            // Skip if this build is no longer the PR head (stale build race)
            const { data: pr } = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: prNumber,
            });

            if (pr.head.sha !== headSha) {
              core.info(`Build is for ${headSha.substring(0, 7)} but PR head is now ${pr.head.sha.substring(0, 7)} — skipping stale comment`);
              return;
            }

            // List files from the downloaded artifact, sanitize names
            const safeNamePattern = /^[\w.\-]+\.(tar\.gz|zip)$/;
            const files = fs.readdirSync('binaries')
              .filter(f => safeNamePattern.test(f))
              .sort();

            const buildRunId = context.payload.workflow_run.id;
            const runUrl = `https://github.com/${context.repo.owner}/${context.repo.repo}/actions/runs/${buildRunId}#artifacts`;
            const shortSha = headSha.substring(0, 7);
            const now = new Date().toISOString().replace('T', ' ').replace(/\.\d+Z$/, ' UTC');

            const newRow = `| \`${shortSha}\` | [Download](${runUrl}) | ${now} |`;

            // Find existing comment
            const { data: comments } = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: prNumber,
            });

            const botComment = comments.find(c =>
              c.user.type === 'Bot' && c.body.includes('PR Build Artifacts')
            );

            let historyRows = [];
            if (botComment) {
              // Extract existing table rows (skip header and separator)
              const lines = botComment.body.split('\n');
              historyRows = lines.filter(l =>
                l.startsWith('|') && !l.startsWith('| Commit') && !l.startsWith('| ---')
              );
            }

            // Prepend new build (latest first)
            historyRows.unshift(newRow);

            const platformList = files.map(f => `- \`${f}\``).join('\n');

            const body = [
              '## PR Build Artifacts',
              '',
              '| Commit | Build | Time (UTC) |',
              '| --- | --- | --- |',
              ...historyRows,
              '',
              '<details>',
              '<summary>Available platforms</summary>',
              '',
              platformList,
              '',
              '</details>',
              '',
              '<details>',
              '<summary>How to install</summary>',
              '',
              '1. Click **Download** for the build you want',
              '2. Download **uploadcare-cli-binaries** zip',
              '3. Unzip it — you\'ll find per-platform archives inside',
              '4. Extract the archive for your platform (e.g. `tar xzf uploadcare-cli_*_darwin_arm64.tar.gz`)',
              '5. Run `./uploadcare`',
              '',
              '</details>',
            ].join('\n');

            if (botComment) {
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: botComment.id,
                body,
              });
            } else {
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: prNumber,
                body,
              });
            }