# This configuration is used to build and test on GitHub Actions only.
# It is not the same configuration that is used by Google DeepMind to create release binaries.
# The "official" binaries are built with Clang 13 on all platforms, and are linked against libc++
# on Linux.
#
# We set CMAKE_INTERPROCEDURAL_OPTIMIZATION=OFF here to reduce build time.
# It is highly recommended that this is set to ON for production builds.
#
# Build speed notes:
#   * The compiler matrix lives in build_matrix.json. Pull requests build the
#     representative "core" subset; pushes to main run the full compiler sweep.
#     (See generate_matrix() in build_steps.sh.)
#   * Studio/Filament and WASM are NOT built in the main matrix - they are covered
#     by the dedicated `studio` and `wasm` jobs below. WASM in particular is built
#     with emcc, which ignores the host compiler, so building it per-compiler added
#     no coverage.
#   * ccache is used to wrap the compiler. PR branches fall back to main's cache, so
#     the expensive (and pinned) Filament build is restored rather than recompiled.

# TODO(matijak): Consider switching Windows to Ninja builds only, this configures slightly faster
# and brings Windows in line with other OSes. Also we wouldn't need to specify the --config option
# in the build step because Ninja doesn't support multiple configurations (unlike MSBuild).

name: build

on:
  push:
    branches:
      - main
    paths-ignore:
      - "doc/**"
      - "**/README.md"
  pull_request:
    paths-ignore:
      - "doc/**"
      - "**/README.md"

# Limit the default GITHUB_TOKEN to read-only. No job here writes via the token:
# checkout reads the repo; ccache/cache and upload-artifact use their own backend
# tokens; the chat notification uses a secret webhook.
permissions:
  contents: read

jobs:
  # Compute the build matrix based on the event: PRs get the "core" representative
  # compiler set, pushes to main get the full sweep.
  setup:
    name: "setup (compute matrix)"
    runs-on: ubuntu-latest
    outputs:
      matrix: ${{ steps.generate.outputs.matrix }}
    steps:
    - uses: actions/checkout@v6
    - name: Generate build matrix
      id: generate
      env:
        GITHUB_EVENT_NAME: ${{ github.event_name }}
      run: bash ./.github/workflows/build_steps.sh generate_matrix

  mujoco:
    needs: setup
    strategy:
      fail-fast: false
      matrix: ${{ fromJson(needs.setup.outputs.matrix) }}

    name: "${{ matrix.label }}"
    runs-on: ${{ matrix.os }}

    steps:
    - uses: actions/checkout@v6

    - name: Prepare Linux
      if: ${{ runner.os == 'Linux' }}
      run: bash ./.github/workflows/build_steps.sh prepare_linux

    - name: Prepare macOS
      if: ${{ runner.os == 'macOS' }}
      run: brew install ninja

    - uses: actions/setup-python@v6
      with:
        python-version: "3.11"

    # uv makes the dependency install much faster, with a cross-run cache. POSIX
    # only: Windows stays on pip (it is not a Python-setup bottleneck, and this
    # keeps the venv activate fixup path untouched there).
    - name: Install uv
      if: ${{ runner.os != 'Windows' }}
      uses: astral-sh/setup-uv@v8.2.0
      with:
        enable-cache: true
        cache-dependency-glob: "python/build_requirements*.txt"

    - name: Prepare Python
      shell: bash
      env:
        TMPDIR: ${{ matrix.tmpdir }}
      run: bash ./.github/workflows/build_steps.sh prepare_python

    # ccache dramatically speeds up warm rebuilds. The key is the matrix label so
    # each compiler gets its own cache; the action's restore-keys let PR branches
    # fall back to main's cache. ccache on Windows/MSVC is finicky and Windows
    # isn't the bottleneck, so we skip it there.
    - name: Setup ccache
      if: ${{ runner.os != 'Windows' }}
      uses: hendrikmuhs/ccache-action@v1.2.23
      with:
        key: ${{ matrix.label }}
        max-size: "1.5G"

    - name: Configure MuJoCo
      env:
        TMPDIR: ${{ matrix.tmpdir }}
        CMAKE_ARGS: ${{ matrix.cmake_args }}
      run: bash ./.github/workflows/build_steps.sh configure_mujoco

    - name: Upload CMake Configure Log
      if: always()
      uses: actions/upload-artifact@v7
      with:
        name: cmake-configure-log-${{ matrix.label }}
        path: build/CMakeFiles/CMakeConfigureLog.yaml
        retention-days: 5

    - name: Build MuJoCo
      working-directory: build
      env:
        CMAKE_BUILD_ARGS: ${{ matrix.cmake_build_args }}
      run: bash ../.github/workflows/build_steps.sh build_mujoco

    - name: Test MuJoCo
      working-directory: build
      run: bash ../.github/workflows/build_steps.sh test_mujoco

    - name: Install MuJoCo
      working-directory: build
      run: bash ../.github/workflows/build_steps.sh install_mujoco

    - name: Copy plugins (POSIX)
      if: ${{ runner.os != 'Windows' }}
      working-directory: build
      env:
        TMPDIR: ${{ matrix.tmpdir }}
      run: bash ../.github/workflows/build_steps.sh copy_plugins_posix

    - name: Copy plugins (Windows)
      if: ${{ runner.os == 'Windows' }}
      working-directory: build
      env:
        TMPDIR: ${{ matrix.tmpdir }}
      run: bash ../.github/workflows/build_steps.sh copy_plugins_window

    - name: Configure samples
      working-directory: sample
      env:
        TMPDIR: ${{ matrix.tmpdir }}
        CMAKE_ARGS: ${{ matrix.cmake_args }}
      run: bash ../.github/workflows/build_steps.sh configure_samples

    - name: Build samples
      working-directory: sample/build
      run: cmake --build . --config=Release ${{ matrix.cmake_build_args }}

    - name: Configure simulate
      working-directory: simulate
      env:
        TMPDIR: ${{ matrix.tmpdir }}
        CMAKE_ARGS: ${{ matrix.cmake_args }}
      run: bash ../.github/workflows/build_steps.sh configure_simulate

    - name: Build simulate
      working-directory: simulate/build
      env:
        CMAKE_BUILD_ARGS: ${{ matrix.cmake_build_args }}
      run: bash ../../.github/workflows/build_steps.sh build_simulate

    - name: Make Python sdist
      shell: bash
      working-directory: python
      env:
        TMPDIR: ${{ matrix.tmpdir }}
      run: bash ../.github/workflows/build_steps.sh make_python_sdist

    - name: Build Python bindings
      if: ${{ runner.os != 'Windows' }}
      shell: bash
      working-directory: python/dist
      env:
        TMPDIR: ${{ matrix.tmpdir }}
        CMAKE_ARGS: ${{ matrix.cmake_args }}
      run: bash ../../.github/workflows/build_steps.sh build_python_bindings

    - name: Install Python bindings
      if: ${{ runner.os != 'Windows' }}
      shell: bash
      working-directory: python/dist
      env:
        TMPDIR: ${{ matrix.tmpdir }}
      run: bash ../../.github/workflows/build_steps.sh install_python_bindings

    - name: Test Python bindings
      if: ${{ runner.os != 'Windows' }}
      shell: bash
      env:
        MUJOCO_GL: disable
        TMPDIR: ${{ matrix.tmpdir }}
      run: bash ./.github/workflows/build_steps.sh test_python_bindings

    # MJX (mujoco.mjx) is covered by the dedicated `mjx` job below; it is
    # compiler-independent so it does not need to run in every matrix job.

    - name: Notify team chat
      shell: bash
      env:
        GCHAT_API_URL: ${{ secrets.GCHAT_API }}
        JOB_URL: "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
        CHATMSG_AUTHOR_NAME: ${{ github.event.head_commit.author.name }}
        CHATMSG_AUTHOR_EMAIL: ${{ github.event.head_commit.author.email }}
        CHATMSG_COMMIT_MESSAGE: ${{ github.event.head_commit.message }}
        CHATMSG_JOB_ID: ${{ matrix.label }}
      if: failure() && github.ref_name == 'main' && github.event_name == 'push' && env.GCHAT_API_URL != ''
      run: bash ./.github/workflows/build_steps.sh notify_team_chat

  # This job quickly determines if MuJoCo Studio is broken. It is the only place
  # Filament is compiled in CI, so ccache here is what keeps the long pole short.
  studio:
    strategy:
      fail-fast: false
      matrix:
        include:
          - os: ubuntu-24.04
            label: "ubuntu-24.04-clang-18-studio"
            cmake_args: >-
              -G Ninja
              -DCMAKE_C_COMPILER:STRING=clang-18
              -DCMAKE_CXX_COMPILER:STRING=clang++-18
              -DMUJOCO_HARDEN:BOOL=ON
          # gcc canary: Filament is compiler-dependent and historically finicky on
          # gcc, so keep one gcc Studio build even though the matrix no longer does.
          - os: ubuntu-24.04
            label: "ubuntu-24.04-gcc-14-studio"
            cmake_args: >-
              -G Ninja
              -DCMAKE_C_COMPILER:STRING=gcc-14
              -DCMAKE_CXX_COMPILER:STRING=g++-14
              -DCMAKE_EXE_LINKER_FLAGS:STRING=-Wl,--no-as-needed
          - os: windows-2025
            label: "windows-2025-ninja-studio"
            cmake_args: >-
              -G Ninja
              -DCMAKE_SYSTEM_VERSION=10.0.26100.0
          - os: macos-15
            label: "macos-15-arm64-studio"
            cmake_args: >-
              -G Ninja
              -DCMAKE_CXX_FLAGS="-Wno-error=deprecated-declarations"
              -DMUJOCO_HARDEN:BOOL=ON

    name: "${{ matrix.label }}"
    runs-on: ${{ matrix.os }}

    steps:
    - uses: actions/checkout@v6

    - name: Prepare Windows (setup MSVC)
      if: ${{ runner.os == 'Windows' }}
      uses: ilammy/msvc-dev-cmd@v1

    - name: Prepare Linux
      if: ${{ runner.os == 'Linux' }}
      run: bash ./.github/workflows/build_steps.sh prepare_linux

    # Key the cache on the Filament pin: hashing cmake/third_party_deps/filament.cmake
    # captures BOTH the pinned commit hash and the FILAMENT_* build flags, so bumping
    # either starts a fresh cache namespace instead of restoring stale artifacts.
    # (Correctness does not depend on this: ccache is content-addressed on the full
    # compiler invocation, so changing any build flag forces a recompile regardless.)
    - name: Setup ccache
      if: ${{ runner.os != 'Windows' }}
      uses: hendrikmuhs/ccache-action@v1.2.23
      with:
        key: ${{ matrix.label }}-filament-${{ hashFiles('cmake/third_party_deps/filament.cmake') }}
        restore-keys: ${{ matrix.label }}-filament-
        max-size: "2.0G"

    - name: Configure Studio
      env:
        CMAKE_ARGS: ${{ matrix.cmake_args }}
      run: bash ./.github/workflows/build_steps.sh configure_studio

    - name: Build Studio
      run: bash ./.github/workflows/build_steps.sh build_studio

    - name: Notify team chat
      shell: bash
      env:
        GCHAT_API_URL: ${{ secrets.GCHAT_API }}
        JOB_URL: "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
        CHATMSG_AUTHOR_NAME: ${{ github.event.head_commit.author.name }}
        CHATMSG_AUTHOR_EMAIL: ${{ github.event.head_commit.author.email }}
        CHATMSG_COMMIT_MESSAGE: ${{ github.event.head_commit.message }}
        CHATMSG_JOB_ID: ${{ matrix.label }}
      if: failure() && github.ref_name == 'main' && github.event_name == 'push' && env.GCHAT_API_URL != ''
      run: bash ./.github/workflows/build_steps.sh notify_team_chat


  # This job quickly determines if WASM bindings are broken.
  wasm:
    name: "ubuntu-24.04-clang-18-wasm"
    runs-on: ubuntu-24.04
    env:
      label: "ubuntu-24.04-clang-18-wasm"
      cmake_args: >-
        -G Ninja
        -DCMAKE_C_COMPILER:STRING=clang-18
        -DCMAKE_CXX_COMPILER:STRING=clang++-18
        -DMUJOCO_HARDEN:BOOL=ON
    steps:
    - uses: actions/checkout@v6

    - name: Setup Node.js for WASM bindings
      uses: actions/setup-node@v6
      with:
        node-version: '20'

    - name: Prepare Linux
      if: ${{ runner.os == 'Linux' }}
      run: bash ./.github/workflows/build_steps.sh prepare_linux

    - name: Setup ccache
      uses: hendrikmuhs/ccache-action@v1.2.23
      with:
        key: ${{ env.label }}
        max-size: "1.5G"

    # For convenience run multiple build_steps functions in a single step.
    - name: Prepare, Build and Test WASM bindings
      env:
        CMAKE_ARGS: ${{ env.cmake_args }}
      run: |
        bash ./.github/workflows/build_steps.sh npm_ci
        bash ./.github/workflows/build_steps.sh setup_emsdk
        bash ./.github/workflows/build_steps.sh build_test_wasm

    - name: Notify team chat
      shell: bash
      env:
        GCHAT_API_URL: ${{ secrets.GCHAT_API }}
        JOB_URL: "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
        CHATMSG_AUTHOR_NAME: ${{ github.event.head_commit.author.name }}
        CHATMSG_AUTHOR_EMAIL: ${{ github.event.head_commit.author.email }}
        CHATMSG_COMMIT_MESSAGE: ${{ github.event.head_commit.message }}
        CHATMSG_JOB_ID: ${{ env.label }}
      if: failure() && github.ref_name == 'main' && github.event_name == 'push' && env.GCHAT_API_URL != ''
      run: bash ./.github/workflows/build_steps.sh notify_team_chat


  # MJX (mujoco.mjx) is pure JAX/XLA and compiler-independent: it imports the
  # mujoco Python package only as a reference, so its tests run once here instead
  # of in every matrix job. MuJoCo is built WITHOUT the C++ test suite (MJX does
  # not need it) to keep the build lean.
  mjx:
    name: "ubuntu-24.04-clang-18-mjx"
    runs-on: ubuntu-24.04
    env:
      TMPDIR: "/tmp"
      CMAKE_ARGS: >-
        -G Ninja
        -DCMAKE_C_COMPILER:STRING=clang-18
        -DCMAKE_CXX_COMPILER:STRING=clang++-18
        -DMUJOCO_HARDEN:BOOL=ON
        -DMUJOCO_BUILD_TESTS:BOOL=OFF
    steps:
    - uses: actions/checkout@v6

    - name: Prepare Linux
      run: bash ./.github/workflows/build_steps.sh prepare_linux

    - uses: actions/setup-python@v6
      with:
        python-version: "3.11"

    - name: Install uv
      uses: astral-sh/setup-uv@v8.2.0
      with:
        enable-cache: true
        cache-dependency-glob: "python/build_requirements*.txt"

    - name: Prepare Python
      run: bash ./.github/workflows/build_steps.sh prepare_python

    - name: Setup ccache
      uses: hendrikmuhs/ccache-action@v1.2.23
      with:
        key: ubuntu-24.04-clang-18-mjx
        max-size: "1.0G"

    - name: Configure MuJoCo
      run: bash ./.github/workflows/build_steps.sh configure_mujoco

    - name: Build MuJoCo
      working-directory: build
      run: bash ../.github/workflows/build_steps.sh build_mujoco

    - name: Install MuJoCo
      working-directory: build
      run: bash ../.github/workflows/build_steps.sh install_mujoco

    - name: Copy plugins
      working-directory: build
      run: bash ../.github/workflows/build_steps.sh copy_plugins_posix

    - name: Make Python sdist
      working-directory: python
      run: bash ../.github/workflows/build_steps.sh make_python_sdist

    - name: Build Python bindings
      working-directory: python/dist
      run: bash ../../.github/workflows/build_steps.sh build_python_bindings

    - name: Install Python bindings
      working-directory: python/dist
      run: bash ../../.github/workflows/build_steps.sh install_python_bindings

    - name: Package MJX
      working-directory: mjx
      run: bash ../.github/workflows/build_steps.sh package_mjx

    - name: Install MJX
      working-directory: mjx
      run: bash ../.github/workflows/build_steps.sh install_mjx

    - name: Test MJX
      working-directory: mjx
      run: bash ../.github/workflows/build_steps.sh test_mjx

    - name: Notify team chat
      shell: bash
      env:
        GCHAT_API_URL: ${{ secrets.GCHAT_API }}
        JOB_URL: "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
        CHATMSG_AUTHOR_NAME: ${{ github.event.head_commit.author.name }}
        CHATMSG_AUTHOR_EMAIL: ${{ github.event.head_commit.author.email }}
        CHATMSG_COMMIT_MESSAGE: ${{ github.event.head_commit.message }}
        CHATMSG_JOB_ID: "ubuntu-24.04-clang-18-mjx"
      if: failure() && github.ref_name == 'main' && github.event_name == 'push' && env.GCHAT_API_URL != ''
      run: bash ./.github/workflows/build_steps.sh notify_team_chat