preview-changes.yml

name: Preview Pages Management

on:
  issue_comment:
    types: [created]
  pull_request:
    branches: [main]
    types: [closed]
    paths-ignore:
      - 'bot_challenges/**'

jobs:
  check-permission:
    name: Check Author & Command
    if: github.event.issue.pull_request && contains(github.event.comment.body, '/preview')
    runs-on: ubuntu-latest
    outputs:
      authorized: ${{ steps.check.outputs.authorized }}
    steps:
      - name: Check user permissions
        id: check
        uses: actions/github-script@v7
        with:
          script: |
            const { owner, repo } = context.repo;
            const username = context.actor;

            const { data: permission } = await github.rest.repos.getCollaboratorPermissionLevel({
              owner,
              repo,
              username,
            });

            const allowed = ['admin', 'write'].includes(permission.permission);
            if (!allowed) {
              core.setFailed(`User @${username} is not authorized to trigger preview deployments.`);
            }
            core.setOutput('authorized', allowed);

  notify-preview-start:
    name: Post Building Comment & Cleanup Trigger
    needs: check-permission
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    outputs:
      pr_num: ${{ steps.pr_data.outputs.pr_num }}
      sha: ${{ steps.pr_data.outputs.sha }}
      ref: ${{ steps.pr_data.outputs.ref }}
      pr_author: ${{ steps.pr_data.outputs.pr_author }}
      comment_id: ${{ steps.create_comment.outputs.comment_id }}
    steps:
      - name: Get PR Information
        id: pr_data
        uses: actions/github-script@v7
        with:
          script: |
            const pr = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: context.issue.number,
            });
            core.setOutput('pr_num', pr.data.number);
            core.setOutput('sha', pr.data.head.sha);
            core.setOutput('ref', pr.data.head.ref);
            core.setOutput('pr_author', pr.data.user.login);

      - name: Post "Preview building" comment
        id: create_comment
        uses: actions/github-script@v7
        with:
          script: |
            const triggerUser = context.actor;
            const prAuthor = "${{ steps.pr_data.outputs.pr_author }}";

            let mentions = `@${triggerUser}`;
            if (prAuthor && prAuthor !== triggerUser) {
              mentions += ` @${prAuthor}`;
            }

            const { data: comment } = await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
              body: `⏳ **Preview building...**\n\ncc ${mentions}`,
            });
            core.setOutput('comment_id', comment.id);

      - name: Delete triggering /preview comment
        uses: actions/github-script@v7
        with:
          script: |
            await github.rest.issues.deleteComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: context.payload.comment.id,
            });

  deploy-preview:
    name: Deploy Preview to Cloudflare Pages
    needs: [check-permission, notify-preview-start]
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
      contents: read
    steps:
      - name: Checkout Curriculum (PR Code)
        uses: actions/checkout@v4
        with:
          path: Curriculum
          ref: ${{ needs.notify-preview-start.outputs.sha }}

      - name: Checkout Engine
        uses: actions/checkout@v4
        with:
          repository: ThePythonLedger/Docusaurus-engine
          path: engine

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: 20
          cache: 'npm'
          cache-dependency-path: engine/package-lock.json

      - name: Build Site Assets
        env:
          DOCUSAURUS_URL: https://pr-${{ needs.notify-preview-start.outputs.pr_num }}.python-ledger-preview.pages.dev
          DOCUSAURUS_BASE_URL: /
        run: |
          cd engine
          npm ci
          npm run build

      - name: Deploy to Cloudflare Pages
        uses: cloudflare/wrangler-action@v4
        id: cloudflare_deploy
        with:
          apiToken: ${{ secrets.CF_API_TOKEN }}
          accountId: ${{ secrets.CF_ACCOUNT_ID }}
          command: pages deploy engine/build --project-name=python-ledger-preview --branch=pr-${{ needs.notify-preview-start.outputs.pr_num }}

      - name: Update Preview Comment with Link
        uses: actions/github-script@v7
        with:
          script: |
            const prNumber = ${{ needs.notify-preview-start.outputs.pr_num }};
            const prAuthor = "${{ needs.notify-preview-start.outputs.pr_author }}";
            const triggerUser = context.actor;
            const previewUrl = `https://pr-${prNumber}.python-ledger-preview.pages.dev`;

            let mentions = `@${triggerUser}`;
            if (prAuthor && prAuthor !== triggerUser) {
              mentions += ` @${prAuthor}`;
            }

            const message = `🚀 **Preview Deployment Ready!**\n\ncc ${mentions}\n\nView changes live at:\n${previewUrl}`;

            await github.rest.issues.updateComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: ${{ needs.notify-preview-start.outputs.comment_id }},
              body: message,
            });

      - name: Mark Preview as Failed
        if: failure()
        uses: actions/github-script@v7
        with:
          script: |
            await github.rest.issues.updateComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: ${{ needs.notify-preview-start.outputs.comment_id }},
              body: `❌ **Preview build failed.** Check the [workflow run](${context.serverUrl}/${context.repo.owner}/${context.repo.repo}/actions/runs/${context.runId}) for details.`,
            });

  cleanup-preview:
    name: Delete Cloudflare Pages Preview
    if: github.event.action == 'closed'
    runs-on: ubuntu-latest
    steps:
      - name: Delete Cloudflare Pages Branch via API
        env:
          CLOUDFLARE_API_TOKEN: ${{ secrets.CF_API_TOKEN }}
          CLOUDFLARE_ACCOUNT_ID: ${{ secrets.CF_ACCOUNT_ID }}
        run: |
          BRANCH_NAME="pr-${{ github.event.number }}"
          PROJECT_NAME="python-ledger-preview"

          echo "Deleting Cloudflare Pages branch: $BRANCH_NAME"

          curl -s -X DELETE \
            "https://api.cloudflare.com/client/v4/accounts/${CLOUDFLARE_ACCOUNT_ID}/pages/projects/${PROJECT_NAME}/branches/${BRANCH_NAME}" \
            -H "Authorization: Bearer ${CLOUDFLARE_API_TOKEN}" \
            -H "Content-Type: application/json"