name: Publish Design System Docs PR Preview

on:
  pull_request:
    types: [opened, synchronize, reopened]
    paths:
      - apps/design-system-docs/**
      - .github/actions/build-design-system-docs/action.yml
      - .github/workflows/ds-docs-pr-preview.yml

# Ensure only one preview build runs per-PR at a time
concurrency:
  group: pr-${{ github.event.pull_request.number }}-preview
  cancel-in-progress: true

jobs:
  preview:
    # Avoid running this workflow for pull requests from forks, which would fail due to missing secrets
    if: github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name

    runs-on: ubuntu-latest

    steps:
      # 1. Checkout the PR code
      - uses: actions/checkout@v4

      # 2. Build the Design System Docs site
      - uses: ./.github/actions/build-design-system-docs

      # 3. Install Wrangler
      - run: npm install -g wrangler

      # 4. Upload a new Worker version and capture the preview URL
      - name: Upload Worker version
        id: upload
        env:
          CLOUDFLARE_ACCOUNT_ID: ${{ secrets.DESIGN_SYSTEM_PREVIEW_CLOUDFLARE_ACCOUNT }}
          CLOUDFLARE_API_TOKEN: ${{ secrets.DESIGN_SYSTEM_PREVIEW_CLOUDFLARE_TOKEN }}
        run: |
          # Run the upload and tee output so it's visible in the GitHub Actions log
          OUT=$(wrangler versions upload --cwd apps/design-system-docs 2>&1 | tee /dev/stderr)

          # Extract the preview URL from the output
          URL=$(echo "$OUT" | grep -oE 'https://[a-z0-9-]+-preview\.a8cds\.workers\.dev/?')

          # Output the URL to the GitHub Actions log for debugging
          echo "URL: $URL"

          # Expose it to later steps
          echo "url=$URL" >> "$GITHUB_OUTPUT"

      # 5. Try to find an existing comment with our marker
      - name: Find preview comment
        id: find_comment
        uses: peter-evans/find-comment@v3
        with:
          issue-number: ${{ github.event.pull_request.number }}
          body-includes: '<!-- cf-preview-comment -->'

      # 6. Create or update a comment that shows the preview URL
      - name: Comment (create or update)
        uses: peter-evans/create-or-update-comment@v4
        with:
          issue-number: ${{ github.event.pull_request.number }}
          comment-id: ${{ steps.find_comment.outputs.comment-id }}
          edit-mode: replace
          body: |
            <!-- cf-preview-comment -->
            **Design System Reference Site Preview:**

            ${{ steps.upload.outputs.url }}

            (Latest commit: ${{ github.event.pull_request.head.sha }})