name: Reviewers - Docs Engineering

# **What it does**: Automatically add reviewers based on paths, but only for the docs-internal repo.
# And sets the 'engineering' label on the PR. It also edits the PR body to add a template
# for asking questions for the sake of being confident about the PRs rollout.
# **Why we have it**: So we can have reviewers automatically without getting open source notifications.
# **Who does it impact**: Docs team.

on:
  pull_request:
    types:
      - edited
      - opened
      - ready_for_review
      - reopened
      - synchronize
    paths:
      - '**.ts'
      - '**.tsx'
      - '**.scss'
      - 'src/**'
      - '!src/**.json' # So that Docs Engineering isn't reviewing automated pipeline data PRs
      - '!src/**.yml' # So that Docs Engineering isn't reviewing automated pipeline data PRs
      - '!src/**.sha' # So that Docs Engineering isn't reviewing automated pipeline data PRs
      - '.github/**'
      - 'config/**'
      - '.devcontainer/**'
      - '**Dockerfile'
      - 'package*.json'
      - .github/workflows/reviewers-docs-engineering.yml

permissions:
  contents: read
  pull-requests: write
  repository-projects: read

jobs:
  reviewers-docs-engineering:
    if: >-
      ${{ github.repository == 'github/docs-internal' &&
          !github.event.pull_request.draft &&
          !contains(github.event.pull_request.labels.*.name, 'reviewers-docs-engineering') &&
          !contains(github.event.pull_request.labels.*.name, 'lockfile-churn-only') &&
          github.event.pull_request.head.ref != 'repo-sync' }}
    runs-on: ubuntu-latest
    env:
      PR: ${{ github.event.pull_request.html_url }}
      GH_TOKEN: ${{ secrets.DOCS_BOT_PAT_BASE }}

    steps:
      - name: Checkout repository
        uses: actions/checkout@v6.0.1

      # Detect PRs that only changed package-lock.json (no engineering source files).
      # These are usually cross-platform `npm install` churn from contributors
      # editing content. We comment with reset instructions instead of pulling in
      # docs-engineering for review.
      - name: Detect lockfile-only churn
        id: detect
        run: |
          changed=$(gh pr diff "$PR" --name-only)
          echo "Changed files:"
          echo "$changed"
          lockfile=$(echo "$changed" | grep -c '^package-lock\.json$' || true)
          other_eng=$(echo "$changed" | grep -cE '(\.tsx?$|\.scss$|^src/|^package\.json$|^\.github/|^config/|^\.devcontainer/|Dockerfile)' || true)
          if [ "$lockfile" -gt 0 ] && [ "$other_eng" -eq 0 ]; then
            echo "lockfile_only=true" >> "$GITHUB_OUTPUT"
          else
            echo "lockfile_only=false" >> "$GITHUB_OUTPUT"
          fi

      - name: Comment and label lockfile-only PRs
        if: steps.detect.outputs.lockfile_only == 'true'
        run: |
          cat > /tmp/lockfile-churn-body.md <<'EOF'
          _Posted by Copilot on behalf of docs-engineering._

          This PR includes `package-lock.json` changes but no engineering files. Please reset the lockfile:

          ```
          git checkout origin/main -- package-lock.json
          git commit -m "Reset package-lock.json"
          git push
          ```

          If the lockfile change is intentional, remove the `lockfile-churn-only` label and request docs-engineering review.
          EOF
          gh pr comment "$PR" --body-file /tmp/lockfile-churn-body.md
          gh pr edit "$PR" --add-label lockfile-churn-only

      - name: Add docs engineering as a reviewer
        if: steps.detect.outputs.lockfile_only != 'true'
        uses: ./.github/actions/retry-command
        with:
          command: gh pr edit $PR --add-reviewer github/docs-engineering --add-label reviewers-docs-engineering