name: Docs checker

on:
  pull_request:

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: ${{ github.ref != 'refs/heads/master' }}

jobs:
  docs-checker:
    name: New doxygen warnings checker
    runs-on: ubuntu-latest

    steps:
    - name: Checkout
      uses: actions/checkout@v6
      with:
        fetch-depth: 4

    - name: Get pull-request commits
      uses: OpenTTD/actions/checkout-pull-request@v6

    - name: Install dependencies
      run: |
        echo "::group::Update apt"
        sudo apt-get update
        echo "::endgroup::"

        echo "::group::Install dependencies"
        sudo apt-get install -y --no-install-recommends \
          doxygen \
          # EOF
        echo "::endgroup::"
      env:
        DEBIAN_FRONTEND: noninteractive

    - name: Build docs for PR
      run: |
        mkdir build

        echo "::group::CMake"
        cmake -S . -B build -DOPTION_DOCS_ONLY=ON -DOPTION_LINE_IN_DOXYGEN_WARNINGS=OFF -DOPTION_DOXYGEN_GS_WARN_FILE="Warnings.GS" -DOPTION_DOXYGEN_AI_WARN_FILE="Warnings.AI" -DOPTION_DOXYGEN_WARN_FILE="Warnings.source"
        echo "::endgroup::"

        echo "::group::Build Source"
        cmake --build build --target docs_source
        mv build/Warnings.source doxygen_warnings.PR
        echo "::endgroup::"

        echo "::group::Build AI"
        cmake --build build --target docs_ai
        mv build/Warnings.AI doxygen_AI_warnings.PR
        echo "::endgroup::"

        echo "::group::Build GS"
        cmake --build build --target docs_game
        mv build/Warnings.GS doxygen_GS_warnings.PR
        echo "::endgroup::"

        rm -r build
        git restore Doxyfile.in src/script/api/Doxyfile_AI.in src/script/api/Doxyfile_GS.in

    - name: Build docs for base branch
      run: |
        git checkout HEAD^
        mkdir build

        echo "::group::CMake"
        cmake -S . -B build -DOPTION_DOCS_ONLY=ON -DOPTION_LINE_IN_DOXYGEN_WARNINGS=OFF -DOPTION_DOXYGEN_GS_WARN_FILE="Warnings.GS" -DOPTION_DOXYGEN_AI_WARN_FILE="Warnings.AI" -DOPTION_DOXYGEN_WARN_FILE="Warnings.source"
        echo "::endgroup::"

        echo "::group::Build Source"
        cmake --build build --target docs_source
        mv build/Warnings.source doxygen_warnings.base
        echo "::endgroup::"

        echo "::group::Build AI"
        cmake --build build --target docs_ai
        mv build/Warnings.AI doxygen_AI_warnings.base
        echo "::endgroup::"

        echo "::group::Build GS"
        cmake --build build --target docs_game
        mv build/Warnings.GS doxygen_GS_warnings.base
        echo "::endgroup::"

        rm -r build

    - name: Compare doxygen warnings and errors
      run: |
        unset FAIL

        diff doxygen_warnings.base doxygen_warnings.PR | grep '^>' && FAIL=1
        diff doxygen_AI_warnings.base doxygen_AI_warnings.PR | grep '^>' && FAIL=1
        diff doxygen_GS_warnings.base doxygen_GS_warnings.PR | grep '^>' && FAIL=1

        if [ $FAIL ]; then
            exit 1;
        fi