name: Deploy PR Preview

on:
  workflow_run:
    workflows: ["Pull Request"]
    types: [completed]

permissions:
  contents: read

jobs:
  preview-gate:
    if: |
      github.event.workflow_run.event == 'pull_request' &&
      github.event.workflow_run.conclusion == 'success'
    name: Validate preview deployment gates
    runs-on: ubuntu-latest
    timeout-minutes: 10
    permissions:
      actions: read
      contents: read
      pull-requests: read
    outputs:
      artifact_name: ${{ steps.preview.outputs.artifact_name }}
      head_sha: ${{ steps.preview.outputs.head_sha }}
      is_fork: ${{ steps.preview.outputs.is_fork }}
      pr_number: ${{ steps.preview.outputs.pr_number }}
      should_deploy: ${{ steps.preview.outputs.should_deploy }}

    steps:
      - name: Checkout trusted preview resolver
        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
        with:
          ref: ${{ github.event.repository.default_branch }}
          path: trusted-preview-resolver
          persist-credentials: false
          sparse-checkout: |
            workers/preview/deploy

      - name: Resolve preview request
        id: preview
        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
        with:
          script: |
            const { resolvePreviewRequest } = require('./trusted-preview-resolver/workers/preview/deploy/resolve_preview_request.cjs');
            await resolvePreviewRequest({ github, context, core });

  deployment_record:
    needs: preview-gate
    if: needs.preview-gate.outputs.should_deploy == 'true'
    name: Create GitHub Deployment
    runs-on: ubuntu-latest
    timeout-minutes: 5
    permissions:
      contents: read
      deployments: write
    outputs:
      deployment_id: ${{ steps.deployment.outputs.result }}
    env:
      HEAD_SHA: ${{ needs.preview-gate.outputs.head_sha }}
      IS_FORK: ${{ needs.preview-gate.outputs.is_fork }}
      PR_NUMBER: ${{ needs.preview-gate.outputs.pr_number }}

    steps:
      - name: Create GitHub Deployment
        if: env.IS_FORK == 'false'
        id: deployment
        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
        with:
          script: |
            const prNumber = process.env.PR_NUMBER;
            const headSha = process.env.HEAD_SHA;
            const deployment = await github.rest.repos.createDeployment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              ref: headSha,
              environment: `preview-pr-${prNumber}`,
              auto_merge: false,
              required_contexts: [],
              description: 'PR Preview Deployment'
            });
            return deployment.data.id;
          result-encoding: string

  deploy-preview:
    needs: [preview-gate, deployment_record]
    if: |
      always() &&
      needs.preview-gate.outputs.should_deploy == 'true' &&
      (needs.deployment_record.result == 'success' || needs.deployment_record.result == 'skipped')
    name: Deploy to Cloudflare Containers
    runs-on: ubuntu-latest
    timeout-minutes: 45
    concurrency:
      group: preview-deploy-${{ needs.preview-gate.outputs.pr_number }}
      cancel-in-progress: true
    environment: preview
    permissions:
      actions: read
      contents: read
    outputs:
      preview_url: ${{ steps.deploy.outputs.preview_url }}
    env:
      ARTIFACT_NAME: ${{ needs.preview-gate.outputs.artifact_name }}
      HEAD_SHA: ${{ needs.preview-gate.outputs.head_sha }}
      IS_FORK: ${{ needs.preview-gate.outputs.is_fork }}
      PR_NUMBER: ${{ needs.preview-gate.outputs.pr_number }}

    steps:
      - name: Checkout trusted preview tooling
        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
        with:
          ref: ${{ github.event.repository.default_branch }}
          path: trusted
          persist-credentials: false
          sparse-checkout: |
            workers/preview

      - name: Download preview image artifact
        uses: actions/download-artifact@018cc2cf5baa6db3ef3c5f8a56943fffe632ef53 # v6
        with:
          name: ${{ env.ARTIFACT_NAME }}
          run-id: ${{ github.event.workflow_run.id }}
          github-token: ${{ github.token }}
          path: ${{ runner.temp }}/preview-image

      - name: Setup Node.js
        uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6
        with:
          node-version: "24"

      - name: Verify preview image artifact checksum
        run: |
          set -euo pipefail

          image_archive="$RUNNER_TEMP/preview-image/sure-preview-image.tar.gz"
          checksum_file="$RUNNER_TEMP/preview-image/sure-preview-image.sha256"
          manifest_file="$RUNNER_TEMP/preview-image/sure-preview-image.manifest.json"
          expected_files="$(mktemp)"
          actual_files="$(mktemp)"

          test -f "$image_archive"
          test -f "$checksum_file"
          test -f "$manifest_file"

          printf '%s\n' \
            sure-preview-image.manifest.json \
            sure-preview-image.sha256 \
            sure-preview-image.tar.gz | sort > "$expected_files"
          find "$RUNNER_TEMP/preview-image" -maxdepth 1 -type f -printf '%f\n' | sort > "$actual_files"

          if ! diff -u "$expected_files" "$actual_files"; then
            echo "Preview image artifact contained unexpected files" >&2
            exit 1
          fi

          expected_checksum="$(tr -d '[:space:]' < "$checksum_file")"
          actual_checksum="$(sha256sum "$image_archive" | awk '{print $1}')"

          if [ "$expected_checksum" != "$actual_checksum" ]; then
            echo "Preview image artifact checksum mismatch" >&2
            exit 1
          fi

          node - "$manifest_file" "$expected_checksum" <<'NODE'
          const fs = require('node:fs');

          const manifestPath = process.argv[2];
          const expectedChecksum = process.argv[3];
          const manifest = JSON.parse(fs.readFileSync(manifestPath, 'utf8'));
          const expectedImageTag = `sure-preview-pr-${process.env.PR_NUMBER}:${process.env.HEAD_SHA}`;
          const expected = {
            artifactVersion: 1,
            archivePath: 'sure-preview-image.tar.gz',
            archiveSha256: expectedChecksum,
            headSha: process.env.HEAD_SHA,
            imageTag: expectedImageTag,
            prNumber: process.env.PR_NUMBER,
          };

          for (const [key, value] of Object.entries(expected)) {
            if (manifest[key] !== value) {
              throw new Error(`Preview image manifest ${key} mismatch`);
            }
          }

          if (!/^sha256:[a-f0-9]{64}$/.test(manifest.imageId || '')) {
            throw new Error('Preview image manifest imageId is invalid');
          }
          NODE

      - name: Prepare trusted preview deploy workspace
        run: |
          set -euo pipefail

          preview_dir="$RUNNER_TEMP/sure-preview-worker"
          rm -rf "$preview_dir"
          mkdir -p "$preview_dir"

          cp trusted/workers/preview/package.json "$preview_dir/package.json"
          cp trusted/workers/preview/package-lock.json "$preview_dir/package-lock.json"
          cp trusted/workers/preview/tsconfig.json "$preview_dir/tsconfig.json"
          cp trusted/workers/preview/wrangler.toml "$preview_dir/wrangler.toml"
          cp -R trusted/workers/preview/src "$preview_dir/src"

          sed -i "s/\${PR_NUMBER}/${PR_NUMBER}/g" "$preview_dir/wrangler.toml"
          sed -i "s/\${PR_NUMBER}/${PR_NUMBER}/g" "$preview_dir/src/index.ts"

          cd "$preview_dir"
          npm ci --ignore-scripts --no-audit --no-fund

      - name: Load preview image artifact
        run: |
          set -euo pipefail

          image_archive="$RUNNER_TEMP/preview-image/sure-preview-image.tar.gz"
          manifest_file="$RUNNER_TEMP/preview-image/sure-preview-image.manifest.json"
          expected_image="sure-preview-pr-${PR_NUMBER}:${HEAD_SHA}"

          gzip -dc "$image_archive" | docker load
          docker image inspect "$expected_image" >/dev/null
          expected_image_id="$(node -e 'const fs = require("node:fs"); process.stdout.write(JSON.parse(fs.readFileSync(process.argv[1], "utf8")).imageId);' "$manifest_file")"
          actual_image_id="$(docker image inspect --format '{{.Id}}' "$expected_image")"

          if [ "$expected_image_id" != "$actual_image_id" ]; then
            echo "Loaded preview image ID did not match artifact manifest" >&2
            exit 1
          fi

      - name: Push preview image to Cloudflare registry
        id: image
        env:
          CLOUDFLARE_ACCOUNT_ID: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
          CLOUDFLARE_API_TOKEN: ${{ secrets.CLOUDFLARE_PREVIEW_API_TOKEN || secrets.CLOUDFLARE_API_TOKEN }}
        run: |
          set -euo pipefail

          cd "$RUNNER_TEMP/sure-preview-worker"
          image_tag="sure-preview-pr-${PR_NUMBER}:${HEAD_SHA}"
          push_log="$RUNNER_TEMP/wrangler-containers-push.log"
          clean_log="$RUNNER_TEMP/wrangler-containers-push.clean.log"

          ./node_modules/.bin/wrangler containers push "$image_tag" 2>&1 | tee "$push_log"
          perl -pe 's/\e\[[0-9;]*[A-Za-z]//g' "$push_log" > "$clean_log"
          image_ref=$(grep -Eo 'registry\.cloudflare\.com/[^[:space:]]+' "$clean_log" | tail -n 1 | tr -d '\r')

          if [ -z "$image_ref" ]; then
            echo "Could not find Cloudflare registry image reference in wrangler output" >&2
            exit 1
          fi

          echo "image_ref=${image_ref}" >> "$GITHUB_OUTPUT"

      - name: Configure trusted preview image reference
        env:
          IMAGE_REF: ${{ steps.image.outputs.image_ref }}
        run: |
          set -euo pipefail

          config_path="$RUNNER_TEMP/sure-preview-worker/wrangler.toml"
          # Use Node instead of sed so the replacement preserves TOML string syntax.
          node - "$config_path" <<'NODE'
          const fs = require('node:fs');

          const configPath = process.argv[2];
          const imageRef = process.env.IMAGE_REF;

          if (!imageRef || !imageRef.startsWith('registry.cloudflare.com/')) {
            throw new Error('Expected a Cloudflare registry image reference');
          }

          const original = fs.readFileSync(configPath, 'utf8');
          const updated = original.replace(/image = "[^"]+"/, `image = ${JSON.stringify(imageRef)}`);
          if (updated === original) {
            throw new Error('Expected wrangler.toml to contain an image entry to rewrite');
          }
          fs.writeFileSync(configPath, updated);
          NODE

          cat "$config_path"

      - name: Deploy to Cloudflare Containers
        id: deploy
        env:
          CLOUDFLARE_ACCOUNT_ID: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
          CLOUDFLARE_API_TOKEN: ${{ secrets.CLOUDFLARE_PREVIEW_API_TOKEN || secrets.CLOUDFLARE_API_TOKEN }}
          CLOUDFLARE_WORKERS_SUBDOMAIN: ${{ secrets.CLOUDFLARE_WORKERS_SUBDOMAIN }}
        run: |
          set -euo pipefail

          cd "$RUNNER_TEMP/sure-preview-worker"
          deploy_log="$RUNNER_TEMP/wrangler-deploy.log"
          clean_deploy_log="$RUNNER_TEMP/wrangler-deploy.clean.log"

          deploy_once() {
            ./node_modules/.bin/wrangler deploy --config wrangler.toml --var "PR_NUMBER:${PR_NUMBER}" 2>&1 | tee "$deploy_log"
          }

          if ! deploy_once; then
            perl -pe 's/\e\[[0-9;]*[A-Za-z]//g' "$deploy_log" > "$clean_deploy_log"

            if grep -F "associated with a different durable object namespace" "$clean_deploy_log" >/dev/null; then
              echo "Detected stale Cloudflare container app state for PR ${PR_NUMBER}; deleting preview Worker and retrying once."
              if ! ./node_modules/.bin/wrangler delete --name "sure-preview-${PR_NUMBER}" --force; then
                echo "Preview Worker delete failed; continuing to the single retry so wrangler deploy reports the final error if the stale state remains." >&2
              fi
              deploy_once
            else
              exit 1
            fi
          fi

          # Get the deployment URL
          PREVIEW_URL="https://sure-preview-${PR_NUMBER}.${CLOUDFLARE_WORKERS_SUBDOMAIN}.workers.dev"
          echo "preview_url=${PREVIEW_URL}" >> "$GITHUB_OUTPUT"

      - name: Warm preview container
        env:
          PREVIEW_URL: ${{ steps.deploy.outputs.preview_url }}
        run: |
          echo "Triggering preview wake-up..."
          curl -fsS --connect-timeout 5 --max-time 15 "$PREVIEW_URL/_container_status" >/dev/null || true

      - name: Collect preview diagnostics
        if: success()
        env:
          PREVIEW_URL: ${{ steps.deploy.outputs.preview_url }}
        run: |
          set -euo pipefail

          diagnostics_file="$RUNNER_TEMP/preview-diagnostics.json"
          last_error=""

          for attempt in $(seq 1 20); do
            if curl -fsS --connect-timeout 5 --max-time 15 "$PREVIEW_URL/_container_status" -o "$diagnostics_file"; then
              if jq -e '.previewReady == true or .previewFailed == true' "$diagnostics_file" >/dev/null; then
                break
              fi
            else
              last_error="curl failed on attempt ${attempt}"
            fi

            sleep 3
          done

          if [ ! -s "$diagnostics_file" ]; then
            jq -n --arg error "${last_error:-preview diagnostics unavailable}" \
              --arg url "$PREVIEW_URL" \
              '{previewReady: false, previewFailed: false, error: $error, previewUrl: $url}' > "$diagnostics_file"
          fi

          jq -c . "$diagnostics_file"

          if jq -e '.previewFailed == true' "$diagnostics_file" >/dev/null; then
            echo "Preview diagnostics from _container_status reported previewFailed=true:" >&2
            jq -c . "$diagnostics_file" >&2
            exit 1
          fi

      - name: Upload preview diagnostics
        if: success()
        uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6
        with:
          name: preview-diagnostics-pr-${{ env.PR_NUMBER }}-${{ env.HEAD_SHA }}
          path: ${{ runner.temp }}/preview-diagnostics.json
          if-no-files-found: error
          retention-days: 3

      - name: Store cleanup metadata
        if: success()
        uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6
        with:
          name: preview-cleanup-pr-${{ env.PR_NUMBER }}
          path: ${{ runner.temp }}/sure-preview-worker/wrangler.toml
          retention-days: 2

  deployment_status:
    needs: [preview-gate, deployment_record, deploy-preview]
    if: |
      always() &&
      needs.preview-gate.outputs.should_deploy == 'true' &&
      needs.preview-gate.outputs.is_fork == 'false' &&
      needs.deployment_record.result == 'success'
    name: Update GitHub Deployment Status
    runs-on: ubuntu-latest
    timeout-minutes: 5
    permissions:
      contents: read
      deployments: write
    env:
      DEPLOYMENT_ID: ${{ needs.deployment_record.outputs.deployment_id }}
      DEPLOY_RESULT: ${{ needs.deploy-preview.result }}
      PREVIEW_URL: ${{ needs.deploy-preview.outputs.preview_url }}

    steps:
      - name: Update Deployment Status
        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
        with:
          script: |
            const state = process.env.DEPLOY_RESULT === 'success' ? 'success' : 'failure';
            const previewUrl = process.env.PREVIEW_URL || undefined;
            await github.rest.repos.createDeploymentStatus({
              owner: context.repo.owner,
              repo: context.repo.repo,
              deployment_id: Number(process.env.DEPLOYMENT_ID),
              state: state,
              environment_url: state === 'success' ? previewUrl : undefined,
              description: state === 'success' ? 'Preview deployed successfully' : 'Preview deployment failed'
            });

  preview_comment:
    needs: [preview-gate, deploy-preview]
    if: needs.deploy-preview.result == 'success'
    name: Comment on PR
    runs-on: ubuntu-latest
    timeout-minutes: 5
    permissions:
      contents: read
      pull-requests: write
    env:
      HEAD_SHA: ${{ needs.preview-gate.outputs.head_sha }}
      PR_NUMBER: ${{ needs.preview-gate.outputs.pr_number }}
      PREVIEW_URL: ${{ needs.deploy-preview.outputs.preview_url }}

    steps:
      - name: Comment on PR
        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
        with:
          script: |
            const previewUrl = process.env.PREVIEW_URL;
            const issueNumber = Number(process.env.PR_NUMBER);
            const headSha = process.env.HEAD_SHA;
            const commentBody = [
              '## 🚀 Preview Deployment Ready',
              '',
              "Your preview environment has been deployed to Cloudflare Containers with the PR's Docker image.",
              '',
              `**Preview URL:** ${previewUrl}`,
              '',
              '> ⏰ This preview is intended to be cleaned up after **24 hours** of the last deployment once the cleanup workflow is live on the default branch.',
              '> 💤 The container will sleep after 30 minutes of inactivity and wake on the next request.',
              '',
              '---',
              `<sub>Deployed from commit ${headSha}</sub>`,
            ].join('\n');

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

            const botComment = comments.find(comment =>
              comment.user.type === 'Bot' &&
              comment.body.includes('Preview Deployment Ready')
            );

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