# .gitea/workflows/nightly-regression.yml
# Nightly Full-Suite Regression Testing
# Sprint: CI/CD Enhancement - Comprehensive Testing
#
# Purpose: Run comprehensive regression tests that are too expensive for PR gating
#   - Full test matrix (all categories)
#   - Extended integration tests
#   - Performance benchmarks with historical comparison
#   - Cross-module dependency validation
#   - Determinism verification
#
# Schedule: Daily at 2:00 AM UTC (off-peak hours)
#
# Notifications: Slack/Teams on failure

name: Nightly Regression

on:
  schedule:
    - cron: '0 2 * * *'  # Daily at 2:00 AM UTC
  workflow_dispatch:
    inputs:
      skip_performance:
        description: 'Skip performance tests'
        type: boolean
        default: false
      skip_determinism:
        description: 'Skip determinism tests'
        type: boolean
        default: false
      notify_on_success:
        description: 'Send notification on success'
        type: boolean
        default: false

env:
  DOTNET_VERSION: '10.0.100'
  DOTNET_NOLOGO: 1
  DOTNET_CLI_TELEMETRY_OPTOUT: 1
  DOTNET_SYSTEM_GLOBALIZATION_INVARIANT: 1
  TZ: UTC

jobs:
  # ===========================================================================
  # PREPARE NIGHTLY RUN
  # ===========================================================================

  prepare:
    name: Prepare Nightly Run
    runs-on: ubuntu-22.04
    outputs:
      run_id: ${{ steps.metadata.outputs.run_id }}
      run_date: ${{ steps.metadata.outputs.run_date }}
      commit_sha: ${{ steps.metadata.outputs.commit_sha }}
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Generate run metadata
        id: metadata
        run: |
          RUN_ID="nightly-$(date -u +%Y%m%d-%H%M%S)"
          RUN_DATE=$(date -u +%Y-%m-%d)
          COMMIT_SHA=$(git rev-parse HEAD)

          echo "run_id=$RUN_ID" >> $GITHUB_OUTPUT
          echo "run_date=$RUN_DATE" >> $GITHUB_OUTPUT
          echo "commit_sha=$COMMIT_SHA" >> $GITHUB_OUTPUT

          echo "## Nightly Regression Run" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "- **Run ID:** $RUN_ID" >> $GITHUB_STEP_SUMMARY
          echo "- **Date:** $RUN_DATE" >> $GITHUB_STEP_SUMMARY
          echo "- **Commit:** $COMMIT_SHA" >> $GITHUB_STEP_SUMMARY

      - name: Check recent commits
        run: |
          echo "### Recent Commits" >> $GITHUB_STEP_SUMMARY
          echo '```' >> $GITHUB_STEP_SUMMARY
          git log --oneline -10 >> $GITHUB_STEP_SUMMARY
          echo '```' >> $GITHUB_STEP_SUMMARY

  # ===========================================================================
  # FULL BUILD VERIFICATION
  # ===========================================================================

  build:
    name: Full Build
    runs-on: ubuntu-22.04
    timeout-minutes: 30
    needs: prepare
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Setup .NET
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: ${{ env.DOTNET_VERSION }}
          include-prerelease: true

      - name: Restore dependencies
        run: dotnet restore src/StellaOps.sln

      - name: Build solution (Release)
        run: |
          START_TIME=$(date +%s)
          dotnet build src/StellaOps.sln --configuration Release --no-restore
          END_TIME=$(date +%s)
          DURATION=$((END_TIME - START_TIME))
          echo "build_time=$DURATION" >> $GITHUB_ENV
          echo "Build completed in ${DURATION}s"

      - name: Report build metrics
        run: |
          echo "### Build Metrics" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "- **Build Time:** ${{ env.build_time }}s" >> $GITHUB_STEP_SUMMARY
          echo "- **Configuration:** Release" >> $GITHUB_STEP_SUMMARY

  # ===========================================================================
  # COMPREHENSIVE TEST SUITE
  # ===========================================================================

  test-pr-gating:
    name: PR-Gating Tests
    runs-on: ubuntu-22.04
    timeout-minutes: 45
    needs: build
    services:
      postgres:
        image: postgres:16
        env:
          POSTGRES_USER: stellaops
          POSTGRES_PASSWORD: stellaops
          POSTGRES_DB: stellaops_test
        ports:
          - 5432:5432
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5

    strategy:
      fail-fast: false
      matrix:
        category:
          - Unit
          - Architecture
          - Contract
          - Integration
          - Security
          - Golden

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

      - name: Setup .NET
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: ${{ env.DOTNET_VERSION }}
          include-prerelease: true

      - name: Run ${{ matrix.category }} Tests
        env:
          STELLAOPS_TEST_POSTGRES_CONNECTION: "Host=localhost;Port=5432;Database=stellaops_test;Username=stellaops;Password=stellaops"
        run: |
          chmod +x .gitea/scripts/test/run-test-category.sh
          .gitea/scripts/test/run-test-category.sh "${{ matrix.category }}"

      - name: Upload Test Results
        uses: actions/upload-artifact@v4
        if: always()
        with:
          name: nightly-test-${{ matrix.category }}
          path: ./TestResults/${{ matrix.category }}
          retention-days: 30

  test-extended:
    name: Extended Tests
    runs-on: ubuntu-22.04
    timeout-minutes: 60
    needs: build
    if: github.event.inputs.skip_performance != 'true'

    strategy:
      fail-fast: false
      matrix:
        category:
          - Performance
          - Benchmark
          - Resilience
          - Observability

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

      - name: Setup .NET
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: ${{ env.DOTNET_VERSION }}
          include-prerelease: true

      - name: Run ${{ matrix.category }} Tests
        run: |
          chmod +x .gitea/scripts/test/run-test-category.sh
          .gitea/scripts/test/run-test-category.sh "${{ matrix.category }}"

      - name: Upload Test Results
        uses: actions/upload-artifact@v4
        if: always()
        with:
          name: nightly-extended-${{ matrix.category }}
          path: ./TestResults/${{ matrix.category }}
          retention-days: 30

  # ===========================================================================
  # DETERMINISM VERIFICATION
  # ===========================================================================

  determinism:
    name: Determinism Verification
    runs-on: ubuntu-22.04
    timeout-minutes: 45
    needs: build
    if: github.event.inputs.skip_determinism != 'true'
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Setup .NET
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: ${{ env.DOTNET_VERSION }}
          include-prerelease: true

      - name: First build
        run: |
          dotnet build src/StellaOps.sln --configuration Release -o ./build-1
          find ./build-1 -name "*.dll" -exec sha256sum {} \; | sort > checksums-1.txt

      - name: Clean and rebuild
        run: |
          rm -rf ./build-1
          dotnet clean src/StellaOps.sln
          dotnet build src/StellaOps.sln --configuration Release -o ./build-2
          find ./build-2 -name "*.dll" -exec sha256sum {} \; | sort > checksums-2.txt

      - name: Compare builds
        id: compare
        run: |
          echo "### Determinism Check" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY

          if diff checksums-1.txt checksums-2.txt > /dev/null; then
            echo "PASS: Builds are deterministic" >> $GITHUB_STEP_SUMMARY
            echo "deterministic=true" >> $GITHUB_OUTPUT
          else
            echo "FAIL: Builds differ" >> $GITHUB_STEP_SUMMARY
            echo "" >> $GITHUB_STEP_SUMMARY
            echo "<details><summary>Differences</summary>" >> $GITHUB_STEP_SUMMARY
            echo "" >> $GITHUB_STEP_SUMMARY
            echo '```diff' >> $GITHUB_STEP_SUMMARY
            diff checksums-1.txt checksums-2.txt >> $GITHUB_STEP_SUMMARY || true
            echo '```' >> $GITHUB_STEP_SUMMARY
            echo "</details>" >> $GITHUB_STEP_SUMMARY
            echo "deterministic=false" >> $GITHUB_OUTPUT
            exit 1
          fi

      - name: Upload checksums
        uses: actions/upload-artifact@v4
        if: always()
        with:
          name: nightly-determinism-checksums
          path: checksums-*.txt
          retention-days: 30

  # ===========================================================================
  # CROSS-MODULE VALIDATION
  # ===========================================================================

  cross-module:
    name: Cross-Module Validation
    runs-on: ubuntu-22.04
    timeout-minutes: 30
    needs: build
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Setup .NET
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: ${{ env.DOTNET_VERSION }}
          include-prerelease: true

      - name: Check for circular dependencies
        run: |
          echo "### Dependency Analysis" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY

          # Build dependency graph
          echo "Analyzing project dependencies..."
          for proj in $(find src -name "*.csproj" ! -path "*/bin/*" ! -path "*/obj/*" | head -50); do
            # Extract ProjectReference entries
            refs=$(grep -oP 'ProjectReference Include="\K[^"]+' "$proj" 2>/dev/null || true)
            if [[ -n "$refs" ]]; then
              basename "$proj" >> deps.txt
              echo "$refs" | while read ref; do
                echo "  -> $(basename "$ref")" >> deps.txt
              done
            fi
          done

          if [[ -f deps.txt ]]; then
            echo "<details><summary>Project Dependencies (first 50)</summary>" >> $GITHUB_STEP_SUMMARY
            echo "" >> $GITHUB_STEP_SUMMARY
            echo '```' >> $GITHUB_STEP_SUMMARY
            head -100 deps.txt >> $GITHUB_STEP_SUMMARY
            echo '```' >> $GITHUB_STEP_SUMMARY
            echo "</details>" >> $GITHUB_STEP_SUMMARY
          fi

      - name: Validate no deprecated APIs
        run: |
          # Check for use of deprecated patterns
          DEPRECATED_COUNT=$(grep -r "Obsolete" src --include="*.cs" | wc -l || echo "0")
          echo "- Obsolete attribute usages: $DEPRECATED_COUNT" >> $GITHUB_STEP_SUMMARY

  # ===========================================================================
  # CODE COVERAGE REPORT
  # ===========================================================================

  coverage:
    name: Code Coverage
    runs-on: ubuntu-22.04
    timeout-minutes: 45
    needs: build
    services:
      postgres:
        image: postgres:16
        env:
          POSTGRES_USER: stellaops
          POSTGRES_PASSWORD: stellaops
          POSTGRES_DB: stellaops_test
        ports:
          - 5432:5432
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Setup .NET
        uses: actions/setup-dotnet@v4
        with:
          dotnet-version: ${{ env.DOTNET_VERSION }}
          include-prerelease: true

      - name: Run tests with coverage
        env:
          STELLAOPS_TEST_POSTGRES_CONNECTION: "Host=localhost;Port=5432;Database=stellaops_test;Username=stellaops;Password=stellaops"
        run: |
          dotnet test src/StellaOps.sln \
            --configuration Release \
            --collect:"XPlat Code Coverage" \
            --results-directory ./TestResults/Coverage \
            --filter "Category=Unit|Category=Integration" \
            --verbosity minimal \
            -- DataCollectionRunSettings.DataCollectors.DataCollector.Configuration.Format=cobertura

      - name: Install ReportGenerator
        run: dotnet tool install -g dotnet-reportgenerator-globaltool

      - name: Generate coverage report
        run: |
          reportgenerator \
            -reports:"./TestResults/Coverage/**/coverage.cobertura.xml" \
            -targetdir:"./TestResults/CoverageReport" \
            -reporttypes:"Html;MarkdownSummary;Cobertura" \
            || true

      - name: Add coverage to summary
        run: |
          echo "### Code Coverage Report" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          if [[ -f "./TestResults/CoverageReport/Summary.md" ]]; then
            cat "./TestResults/CoverageReport/Summary.md" >> $GITHUB_STEP_SUMMARY
          else
            echo "Coverage report generation failed or no coverage data collected." >> $GITHUB_STEP_SUMMARY
          fi

      - name: Upload coverage report
        uses: actions/upload-artifact@v4
        if: always()
        with:
          name: nightly-coverage-report
          path: ./TestResults/CoverageReport
          retention-days: 30

  # ===========================================================================
  # SUMMARY AND NOTIFICATION
  # ===========================================================================

  summary:
    name: Nightly Summary
    runs-on: ubuntu-22.04
    needs:
      - prepare
      - build
      - test-pr-gating
      - test-extended
      - determinism
      - cross-module
      - coverage
    if: always()
    steps:
      - name: Generate final summary
        run: |
          echo "## Nightly Regression Summary" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "**Run ID:** ${{ needs.prepare.outputs.run_id }}" >> $GITHUB_STEP_SUMMARY
          echo "**Date:** ${{ needs.prepare.outputs.run_date }}" >> $GITHUB_STEP_SUMMARY
          echo "**Commit:** ${{ needs.prepare.outputs.commit_sha }}" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "### Job Results" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "| Job | Status |" >> $GITHUB_STEP_SUMMARY
          echo "|-----|--------|" >> $GITHUB_STEP_SUMMARY
          echo "| Build | ${{ needs.build.result }} |" >> $GITHUB_STEP_SUMMARY
          echo "| PR-Gating Tests | ${{ needs.test-pr-gating.result }} |" >> $GITHUB_STEP_SUMMARY
          echo "| Extended Tests | ${{ needs.test-extended.result }} |" >> $GITHUB_STEP_SUMMARY
          echo "| Determinism | ${{ needs.determinism.result }} |" >> $GITHUB_STEP_SUMMARY
          echo "| Cross-Module | ${{ needs.cross-module.result }} |" >> $GITHUB_STEP_SUMMARY
          echo "| Coverage | ${{ needs.coverage.result }} |" >> $GITHUB_STEP_SUMMARY

      - name: Determine overall status
        id: status
        run: |
          if [[ "${{ needs.build.result }}" == "failure" ]] || \
             [[ "${{ needs.test-pr-gating.result }}" == "failure" ]] || \
             [[ "${{ needs.determinism.result }}" == "failure" ]]; then
            echo "status=failure" >> $GITHUB_OUTPUT
          else
            echo "status=success" >> $GITHUB_OUTPUT
          fi

      # Placeholder for notifications - configure webhook URL in secrets
      - name: Send failure notification
        if: steps.status.outputs.status == 'failure'
        run: |
          echo "::warning::Nightly regression failed - notification would be sent here"
          # Uncomment and configure when webhook is available:
          # curl -X POST "${{ secrets.SLACK_WEBHOOK_URL }}" \
          #   -H "Content-Type: application/json" \
          #   -d '{
          #     "text": "Nightly Regression Failed",
          #     "attachments": [{
          #       "color": "danger",
          #       "fields": [
          #         {"title": "Run ID", "value": "${{ needs.prepare.outputs.run_id }}", "short": true},
          #         {"title": "Commit", "value": "${{ needs.prepare.outputs.commit_sha }}", "short": true}
          #       ]
          #     }]
          #   }'

      - name: Send success notification
        if: steps.status.outputs.status == 'success' && github.event.inputs.notify_on_success == 'true'
        run: |
          echo "::notice::Nightly regression passed"

      - name: Exit with appropriate code
        if: steps.status.outputs.status == 'failure'
        run: exit 1