name: Unit Tests

on:
  # push:
  #   branches:
  #     - "dev-v2"
  #   paths:
  #     - ".github/workflows/unit-tests.yml"
  #     - "unit_test/**"
  #     - "src/**"
  # pull_request:
  #   paths:
  #     - ".github/workflows/unit-tests.yml"
  #     - "unit_test/**"
  #     - "src/**"
  workflow_dispatch:

permissions:
  contents: read

jobs:
  select-tests:
    name: Select Unit Test Suites
    runs-on: ubuntu-latest
    outputs:
      has_tests: ${{ steps.select.outputs.has_tests }}
      matrix: ${{ steps.select.outputs.matrix }}

    steps:
      - name: Checkout repository
        uses: actions/checkout@v7
        with:
          fetch-depth: 0
          show-progress: false

      - name: Select affected test suites
        id: select
        env:
          EVENT_NAME: ${{ github.event_name }}
          BEFORE_SHA: ${{ github.event.before }}
          HEAD_SHA: ${{ github.sha }}
          PR_BASE_SHA: ${{ github.event.pull_request.base.sha }}
          PR_HEAD_SHA: ${{ github.event.pull_request.head.sha }}
        run: |
          python3 - <<'PY'
          import json
          import os
          import subprocess

          def matches(path: str, rule: str) -> bool:
              if rule.endswith('/**'):
                  return path.startswith(rule[:-3])
              return path == rule

          with open('unit_test/test-suites.json', encoding='utf-8') as f:
              mapping = json.load(f)

          event_name = os.environ['EVENT_NAME']
          changed_files = []
          run_all = event_name == 'workflow_dispatch'

          if not run_all:
              if event_name == 'pull_request':
                  base_sha = os.environ['PR_BASE_SHA']
                  head_sha = os.environ['PR_HEAD_SHA']
              else:
                  base_sha = os.environ['BEFORE_SHA']
                  head_sha = os.environ['HEAD_SHA']

              if not base_sha or set(base_sha) == {'0'}:
                  run_all = True
              else:
                  diff = subprocess.check_output(
                      ['git', 'diff', '--name-only', base_sha, head_sha],
                      text=True,
                  )
                  changed_files = [line for line in diff.splitlines() if line]

          print('Changed files:')
          for file_path in changed_files:
              print(f'  - {file_path}')

          if run_all or any(any(matches(path, rule) for rule in mapping['runAllOnChanges']) for path in changed_files):
              selected = mapping['suites']
          else:
              selected = []
              for suite in mapping['suites']:
                  if any(any(matches(path, rule) for rule in suite['paths']) for path in changed_files):
                      selected.append(suite)

          matrix = {'suite': selected}
          with open(os.environ['GITHUB_OUTPUT'], 'a', encoding='utf-8') as f:
              f.write(f"has_tests={'true' if selected else 'false'}\n")
              f.write(f"matrix={json.dumps(matrix, separators=(',', ':'))}\n")
          PY

  unit-tests:
    name: ${{ matrix.suite.name }} Unit Tests
    needs: select-tests
    if: ${{ needs.select-tests.outputs.has_tests == 'true' }}
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix: ${{ fromJson(needs.select-tests.outputs.matrix) }}

    steps:
      - name: Checkout repository
        uses: actions/checkout@v7
        with:
          show-progress: false

      - name: Configure unit tests
        run: |
          cmake -S unit_test -B build/unit_test -DCMAKE_BUILD_TYPE=Release

      - name: Build selected unit test target
        run: |
          cmake --build build/unit_test --parallel --target ${{ matrix.suite.buildTarget }}

      - name: Run selected unit tests
        run: |
          ctest --test-dir build/unit_test --output-on-failure -R '${{ matrix.suite.ctestRegex }}'