name: PR Autoformat

# Manual PR hygiene helper: a human comments `/autoformat` to assign the PR
# author and add missing PR-template sections without deleting the author's text.
# This issue_comment workflow never checks out or executes PR code — it checks
# out only the default-branch script and updates PR metadata via the API.

on:
  issue_comment:
    types: [created]

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

concurrency:
  group: pr-autoformat-${{ github.event.issue.number || github.run_id }}
  cancel-in-progress: false

jobs:
  autoformat:
    name: PR Autoformat
    if: >-
      !endsWith(github.actor, '[bot]') &&
      github.event.issue.pull_request != null &&
      contains(github.event.comment.body, '/autoformat')
    runs-on: ubuntu-latest
    timeout-minutes: 5

    steps:
      - name: Checkout default-branch helper
        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0  # v7.0.0
        with:
          ref: ${{ github.event.repository.default_branch }}
          sparse-checkout: .github/scripts/pr-template
          persist-credentials: false

      - name: Set up Python
        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6.2.0
        with:
          python-version: "3.11"

      - name: Autoformat PR body and assign author
        env:
          GH_TOKEN: ${{ github.token }}
          REPO: ${{ github.repository }}
          PR_NUMBER: ${{ github.event.issue.number }}
        run: |
          set -euo pipefail

          pr_json=$(gh pr view "$PR_NUMBER" --repo "$REPO" --json author,body)
          author=$(jq -r '.author.login' <<<"$pr_json")
          body_file=$(mktemp)
          new_body_file=$(mktemp)
          jq -r '.body // ""' <<<"$pr_json" > "$body_file"

          gh api \
            --method POST \
            "/repos/${REPO}/issues/${PR_NUMBER}/assignees" \
            -f "assignees[]=${author}"

          .github/scripts/pr-template/format_body.py "$body_file" "$new_body_file"

          changed=false
          if ! cmp -s "$body_file" "$new_body_file"; then
            gh pr edit "$PR_NUMBER" --repo "$REPO" --body-file "$new_body_file"
            changed=true
          fi

          if [ "$changed" = true ]; then
            gh pr comment "$PR_NUMBER" --repo "$REPO" --body "Autoformatted PR body and assigned @${author}."
          else
            gh pr comment "$PR_NUMBER" --repo "$REPO" --body "Assigned @${author}. PR body already had the expected template sections."
          fi