name: CI

on:
  push:
    branches: [main, develop]
  pull_request:

permissions:
  contents: read

concurrency:
  group: ci-${{ github.ref }}
  cancel-in-progress: true

jobs:
  # ---------------------------------------------------------------------------
  # Static checks: Rule R2 boundary + formatting. Fast, gates the build matrix.
  # ---------------------------------------------------------------------------
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Rule R2 — PDFium boundary check
        run: bash scripts/check_pdfium_boundary.sh

      # Pinned so CI matches the version the tree was formatted with — clang-format
      # output drifts between releases, and an unpinned runner version would cause
      # spurious lint failures.
      - name: Install clang-format (pinned)
        run: pipx install clang-format==22.1.5

      - name: clang-format
        run: |
          clang-format --version
          find engine \( -name '*.cpp' -o -name '*.cc' -o -name '*.h' -o -name '*.hpp' \) \
            -print0 | xargs -0 clang-format --dry-run --Werror

  # ---------------------------------------------------------------------------
  # Build + test on all three platforms (Gate G0: compiles clean everywhere).
  # ---------------------------------------------------------------------------
  build:
    needs: lint
    strategy:
      fail-fast: false
      matrix:
        include:
          - os: ubuntu-latest
            preset: linux-debug
          - os: macos-latest
            preset: macos-debug
          - os: windows-latest
            preset: windows-debug
    runs-on: ${{ matrix.os }}
    env:
      VCPKG_DEFAULT_BINARY_CACHE: ${{ github.workspace }}/.vcpkg-cache
    steps:
      - uses: actions/checkout@v4

      - name: Install Ninja
        uses: seanmiddleditch/gha-setup-ninja@v5

      - name: Set up MSVC environment
        if: runner.os == 'Windows'
        uses: ilammy/msvc-dev-cmd@v1

      # GitHub-hosted runners ship vcpkg preinstalled. VCPKG_INSTALLATION_ROOT is
      # a runner OS env var, so it must be promoted to GITHUB_ENV here — it is
      # NOT visible via the ${{ env.* }} context in a job-level env: block.
      - name: Locate vcpkg
        shell: bash
        run: |
          echo "VCPKG_ROOT=$VCPKG_INSTALLATION_ROOT" >> "$GITHUB_ENV"
          # The runner's preinstalled vcpkg may predate our pinned builtin-baseline;
          # fetch so manifest resolution can find that commit's versions tree.
          git -C "$VCPKG_INSTALLATION_ROOT" fetch --quiet origin || true

      - name: Create vcpkg binary cache dir
        shell: bash
        run: mkdir -p "$VCPKG_DEFAULT_BINARY_CACHE"

      - name: Cache vcpkg artifacts
        uses: actions/cache@v4
        with:
          path: ${{ env.VCPKG_DEFAULT_BINARY_CACHE }}
          key: vcpkg-${{ matrix.os }}-${{ hashFiles('vcpkg.json') }}
          restore-keys: vcpkg-${{ matrix.os }}-

      # vcpkg.json ships without a builtin-baseline; the local bootstrap script
      # normally pins it. In CI we pin it on the fly (idempotent) so the
      # CMakeLists dependency-pinning guard is satisfied.
      - name: Pin vcpkg dependency baseline
        shell: bash
        run: |
          if ! grep -q '"builtin-baseline"' vcpkg.json; then
            "$VCPKG_ROOT/vcpkg" x-update-baseline --add-initial-baseline
          fi

      - name: Configure
        run: cmake --preset ${{ matrix.preset }}

      - name: Build
        run: cmake --build --preset ${{ matrix.preset }}

      - name: Test
        run: ctest --preset ${{ matrix.preset }}