name: Unit plan

# Full runs need only a matrix; shadow import-graph analysis belongs after tests.
on:
  workflow_call:
    inputs:
      selection_mode:
        description: Shadow validates selection; selected applies it only to draft PRs.
        required: false
        default: shadow
        type: string
      defer_shadow:
        description: Emit the full matrix without dependencies; the caller owns the selected-draft exception.
        default: false
        type: boolean

    outputs:
      shards:
        description: JSON array of shard assignments for the unit matrix.
        value: ${{ jobs.plan.outputs.shards }}
      selection_planned:
        description: Whether a selection plan artifact was uploaded for shards to download.
        value: ${{ jobs.plan.outputs.selection_planned }}

permissions:
  contents: read

jobs:
  plan:
    runs-on: ${{ inputs.defer_shadow && 'ubuntu-slim' || 'ubuntu-24.04' }}
    timeout-minutes: 5
    env:
      DEFER_SHADOW: ${{ inputs.defer_shadow }}
    outputs:
      shards: ${{ steps.plan.outputs.shards }}
      selection_planned: ${{ !inputs.defer_shadow }}
    steps:
      - uses: actions/checkout@v6
        with:
          fetch-depth: 2
          sparse-checkout: ${{ inputs.defer_shadow && '/config/scripts/ci/unit-selection/ci-unit-matrix.mjs' || '' }}
          sparse-checkout-cone-mode: false
          persist-credentials: false
      - uses: ./.github/actions/install-node-dependencies
        if: env.DEFER_SHADOW != 'true'
      - name: Plan unit selection
        id: plan
        env:
          ORCA_UNIT_SELECTION_MODE: ${{ inputs.selection_mode }}
          ORCA_PULL_REQUEST_DRAFT: ${{ github.event.pull_request.draft }}
          # Twelve 4-vCPU hosted shards match the old 8-vCPU wall time; the repository variable can request 2 to 16.
          ORCA_UNIT_FULL_SHARD_COUNT: ${{ vars.ORCA_UNIT_FULL_SHARD_COUNT || '12' }}
        run: |
          if [ "$DEFER_SHADOW" = true ]; then
            node config/scripts/ci/unit-selection/ci-unit-matrix.mjs
          else
            node config/scripts/ci/unit-selection/ci-unit-plan.mjs
          fi
      - uses: actions/upload-artifact@v7
        if: env.DEFER_SHADOW != 'true'
        continue-on-error: true
        with:
          name: unit-selection-attempt-${{ github.run_attempt }}
          path: ci-shards/unit-selection.json
          retention-days: 14