name: Backend build, format check, and coverage

# Reusable workflow called from build.yml. Runs the full backend build matrix
# (JDK 21/25 × spring-security on/off), Spotless formatting check, JUnit, and
# posts Jacoco coverage to PRs.
on:
  workflow_call:

permissions:
  contents: read
  actions: read
  security-events: write
  pull-requests: write

jobs:
  build:
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        jdk-version: [21, 25]
        spring-security: [true, false]
    steps:
      - name: Harden Runner
        uses: step-security/harden-runner@58077d3c7e43986b6b15fba718e8ea69e387dfcc # v2.15.1
        with:
          egress-policy: audit
      - name: Checkout repository
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2

      - name: Set up JDK ${{ matrix.jdk-version }}
        uses: actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654 # v5.2.0
        with:
          java-version: ${{ matrix.jdk-version }}
          distribution: "temurin"

      - name: Cache Gradle dependency artifacts
        uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
        with:
          path: |
            ~/.gradle/wrapper
            ~/.gradle/caches/modules-2/files-2.1
            ~/.gradle/caches/modules-2/metadata-2.*
          key: gradle-deps-${{ runner.os }}-jdk-${{ matrix.jdk-version }}-${{ hashFiles('**/gradle/wrapper/gradle-wrapper.properties', '**/*.gradle', '**/*.gradle.kts', 'settings.gradle', 'settings.gradle.kts', 'gradle/libs.versions.toml') }}

      - name: Setup Gradle
        uses: gradle/actions/setup-gradle@f29f5a9d7b09a7c6b29859002d29d24e1674c884 # v5.0.1
        with:
          gradle-version: 9.3.1
          cache-disabled: true

      - name: Install Task
        uses: go-task/setup-task@3be4020d41929789a01026e0e427a4321ce0ad44 # v2.0.0
      - name: Check Java formatting (Spotless)
        if: matrix.jdk-version == 25 && matrix.spring-security == false
        id: spotless-check
        run: task backend:format:check
        continue-on-error: true
        env:
          MAVEN_USER: ${{ secrets.MAVEN_USER }}
          MAVEN_PASSWORD: ${{ secrets.MAVEN_PASSWORD }}
          MAVEN_PUBLIC_URL: ${{ secrets.MAVEN_PUBLIC_URL }}

      - name: Comment on Java formatting failure
        # Only post a comment on PRs. github-script's PR helpers need an
        # issue/PR number, which doesn't exist on merge_group runs.
        if: steps.spotless-check.outcome == 'failure' && github.event_name == 'pull_request'
        continue-on-error: true
        uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0
        with:
          script: |
            const marker = '<!-- java-formatting-check -->';
            const body = [
              marker,
              '### Java Formatting Check Failed',
              '',
              'Your code has formatting issues. Run the following command to fix them:',
              '',
              '```bash',
              'task backend:format',
              '```',
              '',
              'Then commit and push the changes.',
            ].join('\n');
            const { data: comments } = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
            });
            const existing = comments.find(c => c.body.includes(marker));
            if (existing) {
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: existing.id,
                body,
              });
            } else {
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.issue.number,
                body,
              });
            }

      - name: Fail if Java formatting issues found
        if: steps.spotless-check.outcome == 'failure'
        run: |
          echo "============================================"
          echo "  Java Formatting Check Failed"
          echo "============================================"
          echo ""
          echo "Your code has formatting issues."
          echo "Run the following command to fix them:"
          echo ""
          echo "  task backend:format"
          echo ""
          echo "Then commit and push the changes."
          echo "============================================"
          exit 1

      - name: Build with Gradle and spring security ${{ matrix.spring-security }}
        run: task backend:build:ci
        env:
          MAVEN_USER: ${{ secrets.MAVEN_USER }}
          MAVEN_PASSWORD: ${{ secrets.MAVEN_PASSWORD }}
          MAVEN_PUBLIC_URL: ${{ secrets.MAVEN_PUBLIC_URL }}
          DISABLE_ADDITIONAL_FEATURES: ${{ matrix.spring-security }}

      - name: Check Test Reports Exist
        if: always()
        run: |
          declare -a dirs=(
            "app/core/build/reports/tests/"
            "app/core/build/test-results/"
            "app/common/build/reports/tests/"
            "app/common/build/test-results/"
            "app/proprietary/build/reports/tests/"
            "app/proprietary/build/test-results/"
          )
          for dir in "${dirs[@]}"; do
            if [ ! -d "$dir" ]; then
              echo "Missing $dir"
              exit 1
            fi
          done

      - name: Upload Test Reports
        if: always()
        uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
        with:
          name: test-reports-jdk-${{ matrix.jdk-version }}-spring-security-${{ matrix.spring-security }}
          path: |
            app/**/build/reports/jacoco/test
            app/**/build/reports/tests/
            app/**/build/test-results/
            app/**/build/reports/problems/
            build/reports/problems/
          retention-days: 3
          if-no-files-found: warn

      - name: Add coverage to PR with spring security ${{ matrix.spring-security }} and JDK ${{ matrix.jdk-version }}
        # The action only supports the pull_request event (it posts a PR comment),
        # so skip it for merge_group runs and workflow_dispatch.
        if: github.event_name == 'pull_request'
        id: jacoco
        uses: madrapps/jacoco-report@50d3aff4548aa991e6753342d9ba291084e63848 # v1.7.2
        with:
          paths: |
            ${{ github.workspace }}/**/build/reports/jacoco/test/jacocoTestReport.xml
          token: ${{ secrets.GITHUB_TOKEN }}
          min-coverage-overall: 10
          min-coverage-changed-files: 0
          comment-type: summary