name: Label PRs targeting LTS branches

on: [pull_request_target]

permissions:
  pull-requests: write

jobs:
  label:
    runs-on: ubuntu-latest
    steps:
      - name: Check if PR targets LTS branch
        if: startsWith(github.event.pull_request.base.ref, 'stable-')
        uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          script: |
            github.rest.issues.addLabels({
              owner: context.payload.repository.owner.login,
              repo: context.payload.repository.name,
              issue_number: context.payload.pull_request.number,
              labels: ['into-lts']
            });