# Updates the draft GitHub release on every push to main, and applies
# Conventional-Commit-derived labels to incoming PRs. Config lives in
# `.github/release-drafter.yml`. The drafter writes one line per merged
# PR into a draft release tagged `next`; `prepare-release.yml` reads
# that body when bumping versions so the English half of
# `docs/changelog/v<ver>.md` is prefilled.
#
# Cost: one ubuntu-latest job per relevant PR/push event, single API
# call, no compile, no tests. Zero contention with the self-hosted
# Hetzner runners that release.yml uses.

name: release-drafter

on:
  push:
    branches: [main]
  # `pull_request_target` runs in the context of the base branch (main),
  # which is what the autolabeler needs to write labels back to PRs —
  # including PRs from forks, which the regular `pull_request` event
  # doesn't grant write permissions for. We never check out PR code
  # in this workflow (only call the action), so the elevated context
  # is safe.
  pull_request_target:
    types: [opened, reopened, synchronize, edited]

permissions:
  contents: read

jobs:
  update-draft:
    permissions:
      contents: write       # write the draft release object
      pull-requests: write  # apply autolabeler labels to incoming PRs
    runs-on: ubuntu-latest
    steps:
      # Ensure the labels referenced by .github/release-drafter.yml's
      # autolabeler block all exist. release-drafter logs a warning and
      # skips when it tries to apply a label that's missing — labelling
      # itself doesn't fail, but exclude-labels and downstream filtering
      # become silent no-ops. `gh label create … || true` is idempotent:
      # creates on first run, exits with "already exists" on every run
      # after that. Cheap (5 API calls per workflow run, no compile).
      - name: Ensure autolabeler labels exist
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -euo pipefail
          # Format: name|color|description (color without leading #).
          while IFS='|' read -r name color desc; do
            gh label create "$name" --color "$color" --description "$desc" \
              --repo "${{ github.repository }}" 2>/dev/null || true
          done <<'LABELS'
          release-prep|ededed|Automated version-bump PR; excluded from release-drafter changelog
          type: feature|a2eeef|feat: PR — auto-applied by release-drafter
          type: fix|d73a4a|fix: PR — auto-applied by release-drafter
          type: chore|cfd3d7|chore: PR — auto-applied by release-drafter
          type: docs|0075ca|docs: PR — auto-applied by release-drafter
          type: refactor|fbca04|refactor: PR — auto-applied by release-drafter
          LABELS

      - uses: release-drafter/release-drafter@v6
        with:
          config-name: release-drafter.yml
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}