name: PR Preview

on:
  pull_request:
    types:
      - opened
      - synchronize
      - reopened
    paths:
      - .github/workflows/pr-preview.yml
      - docs/**
      - overrides/**
      - mkdocs.yml
      - pyproject.toml
      - uv.lock

concurrency:
  group: pr-preview-${{ github.event.pull_request.number }}
  cancel-in-progress: true

permissions:
  contents: read

jobs:
  build:
    name: Build site
    runs-on: ubuntu-latest

    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          persist-credentials: false

      - name: Setup Python
        uses: actions/setup-python@v5
        with:
          python-version: "3.13"

      - name: Install uv
        uses: astral-sh/setup-uv@v5
        with:
          enable-cache: true
          cache-dependency-glob: uv.lock

      - name: Install dependencies
        run: uv sync --frozen

      - name: Build site
        run: uv run mkdocs build --clean

      - name: Remove production custom domain
        run: rm -f site/CNAME

      - name: Upload site artifact
        uses: actions/upload-artifact@v4
        with:
          name: mkdocs-site
          path: site
          if-no-files-found: error
          retention-days: 7

  deploy:
    name: Deploy preview
    needs: build
    if: github.event.pull_request.head.repo.full_name == github.repository
    runs-on: ubuntu-latest

    permissions:
      contents: read
      deployments: write
      issues: write
      pull-requests: write

    steps:
      - name: Download site artifact
        uses: actions/download-artifact@v4
        with:
          name: mkdocs-site
          path: site

      - name: Deploy to Cloudflare Pages
        id: deploy
        uses: cloudflare/wrangler-action@v3
        with:
          apiToken: ${{ secrets.CF_SANDBOX_API_TOKEN }}
          accountId: ${{ secrets.CF_SANDBOX_ACCOUNT_ID }}
          command: >-
            pages deploy site
            --project-name=${{ vars.CF_SANDBOX_PAGES_PROJECT || 'two-torial-preview' }}
            --branch=pr-${{ github.event.pull_request.number }}
          gitHubToken: ${{ secrets.GITHUB_TOKEN }}

      - name: Comment preview URL
        uses: actions/github-script@v7
        env:
          PREVIEW_URL: ${{ steps.deploy.outputs['pages-deployment-alias-url'] || steps.deploy.outputs['deployment-url'] }}
        with:
          script: |
            const marker = '<!-- pr-preview:cloudflare-pages -->';
            const previewUrl = process.env.PREVIEW_URL;
            const body = `${marker}\nPR preview: ${previewUrl}`;
            const { owner, repo } = context.repo;
            const issue_number = context.issue.number;

            const { data: comments } = await github.rest.issues.listComments({
              owner,
              repo,
              issue_number,
              per_page: 100,
            });

            const existing = comments.find((comment) =>
              comment.user.type === 'Bot' && comment.body?.includes(marker)
            );

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