name: cmake-multiplatform-build
on:
  push:
  pull_request:
    branches: [ "main" ]

concurrency:
  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
  cancel-in-progress: true


jobs:
  build:
    runs-on: ${{ matrix.os }}

    strategy:
      fail-fast: false

      matrix:
        os: [ubuntu-latest, windows-latest, macos-latest]
        build_type: [Release]
        c_compiler: [gcc, clang, cl]
        include:
          - os: windows-latest
            c_compiler: cl
            cpp_compiler: cl
          - os: ubuntu-latest
            c_compiler: gcc
            cpp_compiler: g++
          - os: ubuntu-latest
            c_compiler: clang
            cpp_compiler: clang++
          - os: macos-latest
            c_compiler: clang
            cpp_compiler: clang++
        exclude:
          - os: windows-latest
            c_compiler: gcc
          - os: windows-latest
            c_compiler: clang
          - os: ubuntu-latest
            c_compiler: cl
          - os: macos-latest
            c_compiler: gcc
          - os: macos-latest
            c_compiler: cl

    steps:
    - uses: actions/checkout@v4

    - name: Set reusable strings
      id: strings
      shell: bash
      run: |
        echo "build-output-dir=${{ github.workspace }}/build" >> "$GITHUB_OUTPUT"

    - name: Configure CMake
      run: >
        cmake -B ${{ steps.strings.outputs.build-output-dir }}
        -DCMAKE_CXX_COMPILER=${{ matrix.cpp_compiler }}
        -DCMAKE_C_COMPILER=${{ matrix.c_compiler }}
        -DCMAKE_BUILD_TYPE=${{ matrix.build_type }}
        -S ${{ github.workspace }}

    - name: Build
      # Note that --config is needed because the default Windows generator is a multi-config generator (Visual Studio generator).
      run: cmake --build ${{ steps.strings.outputs.build-output-dir }} --config ${{ matrix.build_type }} -j 2