name: setup-bazel-ci
description: Prepare a Bazel CI runner with shared caches.
inputs:
  target:
    description: Target triple used for cache namespacing.
    required: true
outputs:
  repository-cache-path:
    description: Filesystem path used for the Bazel repository cache.
    value: ${{ steps.configure_bazel_repository_cache.outputs.repository-cache-path }}

runs:
  using: composite
  steps:
    - id: setup_ci
      uses: ./.github/actions/setup-ci

    - name: Set up Bazel
      uses: bazel-contrib/setup-bazel@c5acdfb288317d0b5c0bbd7a396a3dc868bb0f86 # 0.19.0
      # Without an explicit Bazelisk version, setup-bazel leaves PATH unchanged
      # and Windows can use the runner's standalone Bazel, ignoring .bazelversion.
      with:
        bazelisk-version: 1.28.1
        # setup-bazel writes an explicit output_base, which otherwise overrides
        # BAZEL_OUTPUT_USER_ROOT and leaves Bazel's I/O-heavy trees on C:.
        output-base: ${{ steps.setup_ci.outputs.bazel-output-base }}

    - name: Configure Bazel repository cache
      id: configure_bazel_repository_cache
      shell: pwsh
      run: |
        "repository-cache-path=$env:BAZEL_REPOSITORY_CACHE" | Out-File -FilePath $env:GITHUB_OUTPUT -Encoding utf8 -Append

    - name: Expose MSVC SDK environment (Windows)
      if: runner.os == 'Windows'
      shell: pwsh
      run: |
        # Bazel exec-side Rust build scripts do not reliably inherit the MSVC developer
        # shell on GitHub-hosted Windows runners, so discover the latest VS install and
        # ask `VsDevCmd.bat` to materialize the x64/x64 compiler + SDK environment.
        $vswhere = "${env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe"
        if (-not (Test-Path $vswhere)) {
          throw "vswhere.exe not found"
        }

        $installPath = & $vswhere -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath 2>$null
        if (-not $installPath) {
          throw "Could not locate a Visual Studio installation with VC tools"
        }

        $vsDevCmd = Join-Path $installPath 'Common7\Tools\VsDevCmd.bat'
        if (-not (Test-Path $vsDevCmd)) {
          throw "VsDevCmd.bat not found at $vsDevCmd"
        }

        # Keep the export surface explicit: these are the paths and SDK roots that the
        # MSVC toolchain probes need later when Bazel runs Windows exec-platform build
        # scripts such as `aws-lc-sys`.
        $varsToExport = @(
          'INCLUDE',
          'LIB',
          'LIBPATH',
          'PATH',
          'UCRTVersion',
          'UniversalCRTSdkDir',
          'VCINSTALLDIR',
          'VCToolsInstallDir',
          'WindowsLibPath',
          'WindowsSdkBinPath',
          'WindowsSdkDir',
          'WindowsSDKLibVersion',
          'WindowsSDKVersion'
        )

        # `VsDevCmd.bat` is a batch file, so invoke it under `cmd.exe`, suppress its
        # banner, then dump the resulting environment with `set`. Re-export only the
        # approved keys into `GITHUB_ENV` so later steps inherit the same MSVC context.
        $envLines = & cmd.exe /c ('"{0}" -no_logo -arch=x64 -host_arch=x64 >nul && set' -f $vsDevCmd)
        foreach ($line in $envLines) {
          if ($line -notmatch '^(.*?)=(.*)$') {
            continue
          }

          $name = $matches[1]
          $value = $matches[2]
          if ($varsToExport -contains $name) {
            "$name=$value" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
          }
        }

    - name: Compute cache-stable Windows Bazel PATH
      if: runner.os == 'Windows'
      shell: pwsh
      run: ./.github/scripts/compute-bazel-windows-path.ps1