name: PR Docker Build Check

# Lightweight build check on PR only, no image push
# Strategy: Quick verify amd64 + spot check arm64 (backend only)
on:
  pull_request:
    branches:
      - main
      - dev
    paths:
      - 'docker/**'
      - 'Dockerfile*'
      - 'go.mod'
      - 'go.sum'
      - '**.go'
      - 'web/**'
      - '.github/workflows/docker-build.yml'
      - '.github/workflows/pr-docker-check.yml'

jobs:
  # Quick check: amd64 builds for all images
  docker-build-amd64:
    name: Build Check (amd64)
    runs-on: ubuntu-22.04
    permissions:
      contents: read

    strategy:
      fail-fast: false
      matrix:
        include:
          - name: backend
            dockerfile: ./docker/Dockerfile.backend
            test_run: true  # Needs test run
          - name: frontend
            dockerfile: ./docker/Dockerfile.frontend
            test_run: true

    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Build ${{ matrix.name }} image (amd64)
        id: build
        uses: docker/build-push-action@v5
        with:
          context: .
          file: ${{ matrix.dockerfile }}
          platforms: linux/amd64
          push: false
          load: true  # Load into local Docker for test run
          tags: nofx-${{ matrix.name }}:pr-test
          cache-from: type=gha,scope=${{ matrix.name }}-amd64
          cache-to: type=gha,mode=max,scope=${{ matrix.name }}-amd64
          build-args: |
            BUILD_DATE=${{ github.event.pull_request.updated_at }}
            VCS_REF=${{ github.event.pull_request.head.sha }}
            VERSION=pr-${{ github.event.pull_request.number }}

      - name: Test run container (smoke test)
        if: matrix.test_run
        timeout-minutes: 2
        run: |
          echo "🧪 Testing container startup..."

          # Start container
          docker run -d --name test-${{ matrix.name }} \
            --health-cmd="exit 0" \
            nofx-${{ matrix.name }}:pr-test

          # Wait for container to start (up to 30 seconds)
          for i in {1..30}; do
            if docker ps | grep -q test-${{ matrix.name }}; then
              echo "✅ Container started successfully"
              docker logs test-${{ matrix.name }}
              docker stop test-${{ matrix.name }} || true
              exit 0
            fi
            sleep 1
          done

          echo "❌ Container failed to start"
          docker logs test-${{ matrix.name }} || true
          exit 1

      - name: Check image size
        run: |
          SIZE=$(docker image inspect nofx-${{ matrix.name }}:pr-test --format='{{.Size}}')
          SIZE_MB=$((SIZE / 1024 / 1024))

          echo "📦 Image size: ${SIZE_MB} MB"

          # Warning thresholds
          if [ "${{ matrix.name }}" = "backend" ] && [ $SIZE_MB -gt 500 ]; then
            echo "⚠️  Warning: Backend image is larger than 500MB"
          elif [ "${{ matrix.name }}" = "frontend" ] && [ $SIZE_MB -gt 200 ]; then
            echo "⚠️  Warning: Frontend image is larger than 200MB"
          else
            echo "✅ Image size is reasonable"
          fi

  # ARM64 native build check: Uses GitHub native ARM64 runner (fast!)
  docker-build-arm64-native:
    name: Build Check (arm64 native - backend)
    runs-on: ubuntu-22.04-arm  # Native ARM64 runner
    permissions:
      contents: read

    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      # Native ARM64 does not need QEMU, builds directly
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Build backend image (arm64 native)
        uses: docker/build-push-action@v5
        timeout-minutes: 15  # Native builds are faster!
        with:
          context: .
          file: ./docker/Dockerfile.backend
          platforms: linux/arm64
          push: false
          load: true  # Load locally for testing
          tags: nofx-backend:pr-test-arm64
          cache-from: type=gha,scope=backend-arm64
          cache-to: type=gha,mode=max,scope=backend-arm64
          build-args: |
            BUILD_DATE=${{ github.event.pull_request.updated_at }}
            VCS_REF=${{ github.event.pull_request.head.sha }}
            VERSION=pr-${{ github.event.pull_request.number }}

      - name: Test run ARM64 container
        timeout-minutes: 2
        run: |
          echo "🧪 Testing ARM64 container startup..."

          # Start container
          docker run -d --name test-backend-arm64 \
            --health-cmd="exit 0" \
            nofx-backend:pr-test-arm64

          # Wait for startup
          for i in {1..30}; do
            if docker ps | grep -q test-backend-arm64; then
              echo "✅ ARM64 container started successfully"
              docker logs test-backend-arm64
              docker stop test-backend-arm64 || true
              exit 0
            fi
            sleep 1
          done

          echo "❌ ARM64 container failed to start"
          docker logs test-backend-arm64 || true
          exit 1

      - name: ARM64 build summary
        run: |
          echo "✅ Backend ARM64 native build successful!"
          echo "Using GitHub native ARM64 runner - no QEMU needed!"
          echo "Build time is ~3x faster than emulation"

  # Aggregate check results
  check-summary:
    name: Docker Build Summary
    needs: [docker-build-amd64, docker-build-arm64-native]
    runs-on: ubuntu-22.04
    if: always()
    permissions:
      pull-requests: write  # For posting comments
    steps:
      - name: Check build results
        id: check
        run: |
          echo "## 🐳 Docker Build Check Results" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY

          # Check amd64 build
          if [[ "${{ needs.docker-build-amd64.result }}" == "success" ]]; then
            echo "✅ **AMD64 builds**: All passed" >> $GITHUB_STEP_SUMMARY
            AMD64_OK=true
          else
            echo "❌ **AMD64 builds**: Failed" >> $GITHUB_STEP_SUMMARY
            AMD64_OK=false
          fi

          # Check arm64 build
          if [[ "${{ needs.docker-build-arm64-native.result }}" == "success" ]]; then
            echo "✅ **ARM64 build** (native): Backend passed (frontend will be verified after merge)" >> $GITHUB_STEP_SUMMARY
            ARM64_OK=true
          else
            echo "❌ **ARM64 build** (native): Backend failed" >> $GITHUB_STEP_SUMMARY
            ARM64_OK=false
          fi

          echo "" >> $GITHUB_STEP_SUMMARY

          if [ "$AMD64_OK" = true ] && [ "$ARM64_OK" = true ]; then
            echo "### 🎉 All checks passed!" >> $GITHUB_STEP_SUMMARY
            echo "" >> $GITHUB_STEP_SUMMARY
            echo "After merge:" >> $GITHUB_STEP_SUMMARY
            echo "- Full multi-arch builds (amd64 + arm64) will run in parallel" >> $GITHUB_STEP_SUMMARY
            echo "- Estimated time: 15-20 minutes" >> $GITHUB_STEP_SUMMARY
            exit 0
          else
            echo "### ❌ Build checks failed" >> $GITHUB_STEP_SUMMARY
            echo "" >> $GITHUB_STEP_SUMMARY
            echo "Please check the build logs above and fix the errors." >> $GITHUB_STEP_SUMMARY
            exit 1
          fi

      - name: Comment on PR
        if: always() && github.event.pull_request.head.repo.full_name == github.repository
        uses: actions/github-script@v7
        with:
          script: |
            const amd64Status = '${{ needs.docker-build-amd64.result }}';
            const arm64Status = '${{ needs.docker-build-arm64-native.result }}';

            const successIcon = '✅';
            const failIcon = '❌';

            const comment = [
              '## 🐳 Docker Build Check Results',
              '',
              `**AMD64 builds**: ${amd64Status === 'success' ? successIcon : failIcon} ${amd64Status}`,
              `**ARM64 build** (native runner): ${arm64Status === 'success' ? successIcon : failIcon} ${arm64Status}`,
              '',
              amd64Status === 'success' && arm64Status === 'success'
                ? '### 🎉 All Docker builds passed!\n\n✨ Using GitHub native ARM64 runners - 3x faster than emulation!\n\nAfter merge, full multi-arch builds will run in ~10-12 minutes.'
                : '### ⚠️ Some builds failed\n\nPlease check the Actions tab for details.',
              '',
              '<sub>Checked: Backend (amd64 + arm64 native), Frontend (amd64) | Powered by GitHub ARM64 Runners</sub>'
            ].join('\n');

            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.payload.pull_request.number,
              body: comment
            });