ci.yml

name: CI

# Build, test and lint CppNCorr. Triggered on pushes and pull requests targeting
# main and newversion. Kept deliberately fast: GCC on ubuntu-latest, system
# dependencies from apt (no GPU, no large dataset downloads, no source builds of
# OpenCV etc.).
on:
  push:
    branches: [main, newversion]
  pull_request:
    branches: [main, newversion]
  workflow_dispatch:

# Cancel superseded runs on the same ref to save CI minutes.
concurrency:
  group: ci-${{ github.ref }}
  cancel-in-progress: true

env:
  DEBIAN_FRONTEND: noninteractive
  # CMake >= 3.21 on the runner sets PROJECT_IS_TOP_LEVEL automatically.
  CMAKE_ARGS: -DCMAKE_POLICY_VERSION_MINIMUM=3.5

jobs:
  build:
    name: build (gcc, ubuntu-latest)
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Install dependencies
        run: |
          sudo apt-get update
          sudo apt-get install -y --no-install-recommends \
            build-essential cmake \
            libopencv-dev libfftw3-dev libsuitesparse-dev \
            libopenblas-dev liblapack-dev nlohmann-json3-dev libomp-dev

      - name: Configure (top-level, tests enabled)
        run: cmake -S . -B build $CMAKE_ARGS

      - name: Build library + tests
        run: cmake --build build -j "$(nproc)"

  test:
    name: test (unit + integration via ctest)
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Install dependencies
        run: |
          sudo apt-get update
          sudo apt-get install -y --no-install-recommends \
            build-essential cmake \
            libopencv-dev libfftw3-dev libsuitesparse-dev \
            libopenblas-dev liblapack-dev nlohmann-json3-dev libomp-dev

      - name: Configure
        run: cmake -S . -B build $CMAKE_ARGS

      - name: Build test targets
        run: cmake --build build --target ncorr_unit_tests ncorr_engine_tests -j "$(nproc)"

      - name: Run unit tests (fast)
        working-directory: build
        run: ctest --output-on-failure -L unit

      - name: Run integration tests (ohtcfrp)
        working-directory: build
        env:
          OMP_NUM_THREADS: "2"
        # Integration DIC is compute-heavy; give it a generous timeout. The very
        # slow end-to-end cases (label "e2e") are excluded here to keep CI fast —
        # they run locally / on demand (see docs/developer_guide.md).
        run: ctest --output-on-failure --timeout 1200 -L integration

  lint:
    name: lint (clang-format on changed files)
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Install clang-format (pinned)
        # Pin the exact version: apt ships different clang-format majors across
        # runner images, which disagree with the version used to format the tree.
        run: python3 -m pip install --quiet "clang-format==18.1.8"

      - name: clang-format --dry-run on changed C/C++ files
        run: |
          # Always use the pinned pip binary explicitly (the runner image also
          # ships a different-major clang-format on PATH).
          CF="$(python3 -c 'import clang_format, os; print(os.path.join(os.path.dirname(clang_format.__file__), "data", "bin", "clang-format"))')"
          "$CF" --version
          # Determine the base ref to diff against.
          if [ "${{ github.event_name }}" = "pull_request" ]; then
            BASE="origin/${{ github.base_ref }}"
            git fetch origin "${{ github.base_ref }}" || true
          else
            BASE="${{ github.event.before }}"
          fi
          # Lint files ADDED on this branch (diff-filter=A). Pre-existing legacy
          # files that only received small edits are intentionally not reformatted
          # wholesale; the .clang-format style applies to new code on this branch.
          CHANGED=$(git diff --name-only --diff-filter=A "$BASE" HEAD 2>/dev/null \
                    | grep -E '\.(c|cc|cpp|cxx|h|hpp)$' || true)
          if [ -z "$CHANGED" ]; then
            echo "No newly added C/C++ files to lint."
            exit 0
          fi
          echo "Linting:"; echo "$CHANGED"
          # --dry-run --Werror fails if any file is not formatted.
          "$CF" --dry-run --Werror $CHANGED

  coverage:
    name: Coverage (gcov → Codecov)
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Install dependencies
        run: |
          sudo apt-get update
          sudo apt-get install -y \
            cmake build-essential \
            libopencv-dev \
            libfftw3-dev \
            libsuitesparse-dev \
            liblapack-dev libblas-dev \
            libomp-dev \
            gcovr

      - name: Configure (coverage instrumentation)
        run: >
          cmake -S . -B build
          -DCMAKE_BUILD_TYPE=Debug
          -DCMAKE_CXX_FLAGS="--coverage -O0 -g"
          -DCMAKE_C_FLAGS="--coverage -O0 -g"
          -DCMAKE_EXE_LINKER_FLAGS="--coverage"

      - name: Build
        run: cmake --build build -j"$(nproc)"

      - name: Run tests
        working-directory: build
        run: ctest --output-on-failure || echo "ctest returned non-zero (continuing for coverage)"

      - name: Generate coverage report (Cobertura XML)
        run: >
          gcovr --root .
          --exclude 'build/'
          --exclude 'test/'
          --exclude 'tests/'
          --xml-pretty --output coverage.xml
          --print-summary || true

      - name: Upload coverage to Codecov
        uses: codecov/codecov-action@v4
        with:
          files: ./coverage.xml
          flags: unittests
          name: cppncorr-coverage
          token: ${{ secrets.CODECOV_TOKEN }}
          fail_ci_if_error: false