name: Backport

on:
  pull_request_target:
    types: [closed, labeled]

permissions:
  contents: read

jobs:
  pull-request:
    runs-on: ubuntu-latest
    permissions:
      contents: write
      pull-requests: write
    if: github.repository_owner == 'akuity' && github.event.pull_request.merged && (github.event_name != 'labeled' || startsWith('backport/', github.event.label.name))
    steps:
    - name: Checkout
      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
    - name: Create backport PRs
      uses: korthout/backport-action@be567af183754f6a5d831ae90f648954763f17f5 # v3.1.0
      # xref: https://github.com/korthout/backport-action#inputs
      with:
        # Use token to allow workflows to be triggered for the created PR
        github_token: ${{ secrets.AKUITYBOT_PAT }}
        # Match labels with pattern `backport/<target-branch>`
        label_pattern: '^backport\/([^ ]+)$'
        # A title which matches the linter constraints for semantic PR titles,
        # while still being descriptive about the target branch
        pull_title: 'chore(backport ${target_branch}): ${pull_title}'
        # Simpler PR description than default
        pull_description: |-
          Automated backport to `${target_branch}`, triggered by a label in #${pull_number}.
        # Copy any labels (excluding those starting with "backport/") to the backport PR
        copy_labels_pattern: '^(?!backport\/).*'
        # Copy associated people to the backport PR
        copy_assignees: true
        copy_requested_reviewers: true
        # Skip any merge commits in the source PR
        merge_commits: 'skip'
        # Automatically detect "squash and merge" instead of copying all
        # commits from the source PR to the backport PR
        experimental: >
          {
            "detect_merge_method": true
          }
