preview.yml

name: PR Preview Workflow

on:
  pull_request_target:
    types:
      - opened
      - synchronize
      - closed

jobs:
  build-and-preview:
    if: github.event.action == 'opened' || github.event.action == 'synchronize'
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v3
        with:
          ref: ${{ github.event.pull_request.head.sha }}

      - name: Setup Julia
        uses: julia-actions/setup-julia@v2
        with:
          version: '1.10'

      - name: Set up Quarto
        uses: quarto-dev/quarto-actions/setup@v2
        with:
          version: pre-release

      - name: Restore cached _freeze folder
        id: cache-primes-restore
        uses: actions/cache/restore@v4
        with:
          path: |
            _freeze/
          key: ${{ runner.os }}-primes-${{ github.run_id }}
          restore-keys: |
            ${{ runner.os }}-primes

      - name: Render Quarto site
        run: quarto render

      - name: Save _freeze folder
        id: cache-primes-save
        uses: actions/cache/save@v4
        with:
          path: |
            _freeze/
          key: ${{ runner.os }}-primes-${{ github.run_id }}

      - name: Checkout gh-pages branch
        uses: actions/checkout@v3
        with:
          ref: gh-pages
          path: gh-pages

      - name: Deploy Preview to GitHub Pages
        run: |
          PR_NUMBER=${{ github.event.pull_request.number }}
          PREVIEW_DIR="pr-previews/${PR_NUMBER}"
          mkdir -p gh-pages/${PREVIEW_DIR}
          cp -r _site/* gh-pages/${PREVIEW_DIR}
          cd gh-pages
          git config --global user.name "github-actions[bot]"
          git config --global user.email "github-actions[bot]@users.noreply.github.com"
          git add .
          git commit -m "Deploy preview for PR ${PR_NUMBER}"
          git push
        env:
          GH_PAT: ${{ secrets.GH_PAT }}

  delete-preview-directory:
    if: github.event.action == 'closed' || github.event.pull_request.merged == true
    runs-on: ubuntu-latest
    steps:
      - name: Checkout gh-pages branch
        uses: actions/checkout@v3
        with:
          ref: gh-pages

      - name: Remove PR Preview Directory
        run: |
          PR_NUMBER=${{ github.event.pull_request.number }}
          PREVIEW_DIR="pr-previews/${PR_NUMBER}"
          git config --global user.name "github-actions[bot]"
          git config --global user.email "github-actions[bot]@users.noreply.github.com"
          rm -rf ${PREVIEW_DIR}
          git add .
          git commit -m "Remove preview for merged PR #${PR_NUMBER}"
          git push
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

  comment-preview-url:
    needs: build-and-preview
    if: needs.build-and-preview.result == 'success'
    runs-on: ubuntu-latest
    steps:
      - name: Comment Preview URL
        uses: actions/github-script@v7
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            const prNumber = context.payload.pull_request.number;
            const repoName = context.repo.repo;
            const previewUrl = `https://turinglang.org/${repoName}/pr-previews/${prNumber}`;
            const commentBody = `Preview the changes: ${previewUrl}, Please avoid using the search feature and navigation bar in PR previews!`;
            const botUsername = 'github-actions[bot]';
  
            // Check for existing comments by the bot
            const existingComments = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: prNumber,
            });
  
            const botComment = existingComments.data.find(
              (comment) => comment.user.login === botUsername
            );
  
            if (botComment) {
              // Update the existing comment
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: botComment.id,
                body: commentBody,
              });
            } else {
              // Create a new comment
              await github.rest.issues.createComment({
                issue_number: prNumber,
                owner: context.repo.owner,
                repo: context.repo.repo,
                body: commentBody,
              });
            }