pre-review.yml

name: PR Pre-review

on:
  pull_request_target:
    branches: [ master ]
    types: [opened, synchronize, reopened, closed]
  pull_request_review:
    types: [submitted]

permissions:
  contents: read
  pull-requests: write
  issues: write

env:
  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

jobs:
  pre-review:
    if: github.event_name == 'pull_request_target' && github.event.action != 'closed'
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4
        with:
          repository: ${{ github.event.pull_request.head.repo.full_name }}
          ref: ${{ github.event.pull_request.head.sha }}
          fetch-depth: 50
          
      - name: Fetch master branch
        run: git fetch origin master

      - name: Check for labelled PR to skip
        id: check-skip
        run: |
          LABELS=$(gh pr view ${{ github.event.pull_request.number }} \
            -R "${{ github.event.pull_request.base.repo.full_name }}" \
            --json labels --jq ".labels[].name")

          if echo "$LABELS" | grep -Eiq 'Out of scope|Consideration / WIP'; then
            echo "Skipping pre-review for non-scoped contributions."
            echo "skip=true" >> $GITHUB_OUTPUT
          else
            echo "Eligible for pre-review"
            echo "skip=false" >> $GITHUB_OUTPUT
          fi

      - uses: actions/setup-node@v4
        if: steps.check-skip.outputs.skip != 'true'
        with:
          node-version: 20
          cache: 'npm'


      - name: Collect information
        if: steps.check-skip.outputs.skip != 'true'
        run: |
          echo "Setting environment variables for preReview.js"
          setEnv() { echo "$1=${!1}" >> $GITHUB_ENV; }

          PR_NUMBER=${{ github.event.pull_request.number }}
          setEnv "PR_NUMBER"

          CONTRIBUTOR=${{ github.event.pull_request.user.login }}
          setEnv "CONTRIBUTOR"
          echo "Contributor github handle: $CONTRIBUTOR"

          BASE_REPO=${{ github.event.pull_request.base.repo.full_name }}
          setEnv "BASE_REPO"

          HEAD_REF=${{ github.event.pull_request.head.ref }}
          setEnv "HEAD_REF"

          git fetch origin ${{ github.event.pull_request.base.ref }}
          MERGE_BASE=$(git merge-base origin/${{ github.event.pull_request.base.ref }} HEAD)
          setEnv "MERGE_BASE"

          CHANGED_FILES=$(gh pr view $PR_NUMBER -R "$BASE_REPO" --json files -q '.files[].path')
          echo "CHANGED_FILES<<EOF" >> $GITHUB_ENV
          printf '%s\n' "$CHANGED_FILES" >> $GITHUB_ENV
          echo "EOF" >> $GITHUB_ENV

          GITHUB_PERMISSION_ROLE=$(gh api "repos/$BASE_REPO/collaborators/$CONTRIBUTOR/permission" -q '.role_name' 2>/dev/null || echo 'unknown')
          setEnv "GITHUB_PERMISSION_ROLE"

      - name: Run "preReview" script
        if: steps.check-skip.outputs.skip != 'true'
        id: pre-review
        run: |
          PR_NUMBER=${{ github.event.pull_request.number }}
          REVIEW_MESSAGE=$(node ./generators/pre-review/preReview.js "$CONTRIBUTOR" "$CHANGED_FILES" "$GITHUB_PERMISSION_ROLE")

          echo "REVIEW_MESSAGE<<EOF" >> $GITHUB_ENV
          echo "$REVIEW_MESSAGE" >> $GITHUB_ENV
          echo "EOF" >> $GITHUB_ENV

          echo "===== REVIEW_MESSAGE ====="
          echo "$REVIEW_MESSAGE"
          echo "=========================="

          echo "Submit review comment"
          gh pr comment "$PR_NUMBER" --body "$REVIEW_MESSAGE" -R "${{ github.event.pull_request.base.repo.full_name }}"

          echo "Handle 'Changes Requested' label and contributor assignment"
          CURRENT_MONTH=$(date +%m)

          if echo "$REVIEW_MESSAGE" | grep -q '\- \[ \]'; then
            if [[ "$GITHUB_PERMISSION_ROLE" != "unknown" ]]; then
              echo "Assigning contributor: $CONTRIBUTOR"
              gh pr edit "$PR_NUMBER" --add-assignee "$CONTRIBUTOR" -R "${{ github.event.pull_request.base.repo.full_name }}" || true
            else
              echo "Contributor $CONTRIBUTOR is not a collaborator — skipping assignment"
            fi

            gh pr edit "$PR_NUMBER" --add-label "Changes Requested" -R "${{ github.event.pull_request.base.repo.full_name }}"
            gh pr edit "$PR_NUMBER" --remove-label "Awaiting Maintainer Validation" -R "${{ github.event.pull_request.base.repo.full_name }}"
          else
            gh pr edit "$PR_NUMBER" --add-label "Awaiting Maintainer Validation" -R "${{ github.event.pull_request.base.repo.full_name }}"
            gh pr edit "$PR_NUMBER" --remove-label "Changes Requested" -R "${{ github.event.pull_request.base.repo.full_name }}"

            if [[ "$CURRENT_MONTH" == "10" ]]; then
              echo "Adding 'hacktoberfest-accepted' as no review detected"
              gh pr edit "$PR_NUMBER" --add-label "hacktoberfest-accepted" -R "${{ github.event.pull_request.base.repo.full_name }}"
            fi
          fi

          echo "Handle 'invalid' label"
          if echo "$REVIEW_MESSAGE" | grep -q -Eqi 'empty file'; then
            gh pr edit "$PR_NUMBER" --add-label "invalid" -R "${{ github.event.pull_request.base.repo.full_name }}"
          else
            gh pr edit "$PR_NUMBER" --remove-label "invalid" -R "${{ github.event.pull_request.base.repo.full_name }}"
          fi

          echo "Handle 'Conflict present' label"
          if echo "$REVIEW_MESSAGE" | grep -q -Eqi '/icon'; then
            gh pr edit "$PR_NUMBER" --add-label "Conflict present" -R "${{ github.event.pull_request.base.repo.full_name }}"
          else
            gh pr edit "$PR_NUMBER" --remove-label "Conflict present" -R "${{ github.event.pull_request.base.repo.full_name }}"
          fi

        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

  remove-awaiting-on-merge:
    if: github.event_name == 'pull_request_target' && github.event.action == 'closed'
    runs-on: ubuntu-latest
    steps:
      - name: Remove 'Awaiting Maintainer Validation' on merged PR
        run: |
          if [ "${{ github.event.pull_request.merged }}" == "true" ]; then
            echo "PR merged — removing 'Awaiting Maintainer Validation' label"
            gh pr edit ${{ github.event.pull_request.number }} --remove-label "Awaiting Maintainer Validation" -R "${{ github.event.pull_request.base.repo.full_name }}"
          else
            echo "PR closed but not merged — skipping label removal"
          fi
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}