name: "pr-split score"
description: "Score a PR's complexity and suggest splits when it's too large"
branding:
  icon: git-pull-request
  color: blue

inputs:
  max-loc:
    description: "Maximum target diff lines per sub-PR"
    default: "400"
  min-loc:
    description: "Minimum target diff lines per sub-PR"
    default: ""
  partition-strategy:
    description: "Backend for partitioning (graph or cp_sat)"
    default: "graph"
  priority:
    description: "Grouping priority (orthogonal or logical)"
    default: "orthogonal"
  threshold-groups:
    description: "Minimum suggested groups before showing the split plan"
    default: "2"
  python-version:
    description: "Python version to use"
    default: "3.12"
  post-comment:
    description: "Whether to post a PR comment with the results"
    default: "true"

outputs:
  total-loc:
    description: "Total lines of code in the PR diff"
    value: ${{ steps.score.outputs.total_loc }}
  total-groups:
    description: "Number of suggested groups"
    value: ${{ steps.score.outputs.total_groups }}
  objective:
    description: "Plan objective score (lower is better)"
    value: ${{ steps.score.outputs.objective }}
  should-split:
    description: "Whether the PR should be split (true/false)"
    value: ${{ steps.score.outputs.should_split }}

runs:
  using: composite
  steps:
    - name: Install uv
      uses: astral-sh/setup-uv@v4

    - name: Set up Python
      shell: bash
      env:
        UV_PYTHON_VERSION: ${{ inputs.python-version }}
      run: uv python install "$UV_PYTHON_VERSION"

    - name: Install pr-split
      shell: bash
      env:
        PARTITION_STRATEGY: ${{ inputs.partition-strategy }}
      run: |
        if [ "$PARTITION_STRATEGY" = "cp_sat" ]; then
          uv tool install "${{ github.action_path }}[cp-sat]"
        else
          uv tool install "${{ github.action_path }}"
        fi

    - name: Score PR
      id: score
      shell: bash
      env:
        MAX_LOC: ${{ inputs.max-loc }}
        MIN_LOC: ${{ inputs.min-loc }}
        PARTITION_STRATEGY: ${{ inputs.partition-strategy }}
        PRIORITY: ${{ inputs.priority }}
        THRESHOLD_GROUPS: ${{ inputs.threshold-groups }}
        PR_NUMBER: ${{ github.event.pull_request.number }}
        BASE_BRANCH: ${{ github.event.pull_request.base.ref }}
        HEAD_BRANCH: ${{ github.event.pull_request.head.ref }}
      run: python "${{ github.action_path }}/scripts/score_pr.py"

    - name: Post comment
      if: inputs.post-comment == 'true' && steps.score.outputs.should_split == 'true'
      uses: actions/github-script@v7
      with:
        script: |
          const fs = require('fs');
          const body = fs.readFileSync('${{ steps.score.outputs.comment_path }}', 'utf8');
          const { data: comments } = await github.rest.issues.listComments({
            owner: context.repo.owner,
            repo: context.repo.repo,
            issue_number: context.payload.pull_request.number,
          });
          const existing = comments.find(c => c.body.includes('<!-- pr-split-score -->'));
          if (existing) {
            await github.rest.issues.updateComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: existing.id,
              body,
            });
          } else {
            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.payload.pull_request.number,
              body,
            });
          }