# A pull request's title becomes its commit on main (squash merges, .gitea/default_merge_message), so it must be a
# conventional commit: the release workflow versions releases and writes the changelog from them. Required to merge
# (branch protection, dhkatz/infra modules/app-repo).
name: Pull request

on:
  pull_request:
    types: [opened, edited, reopened, synchronize]

jobs:
  title:
    runs-on: ubuntu-latest
    steps:
      - name: Conventional commit title
        env:
          TITLE: ${{ github.event.pull_request.title }}
          BRANCH: ${{ github.head_ref }}
          AUTHOR: ${{ github.event.pull_request.user.login }}
        run: |
          types="feat|fix|perf|refactor|docs|test|build|ci|chore|style|revert"
          conventional="^($types)(\([a-z0-9][a-z0-9./_-]*\))?!?: [^ ]"
          if ! [[ "$TITLE" =~ $conventional ]]; then
            echo "::error::The title becomes the commit on main, so it must be a conventional commit: type(scope): summary, e.g. \"feat(api): room bans\" or \"fix: crash on an empty catalog\" (! before the colon for a breaking change). Types: ${types//|/, }."
            exit 1
          fi
          if [[ "$TITLE" =~ ^chore\(release\) ]] && [[ "$BRANCH" != release || "$AUTHOR" != release-bot ]]; then
            echo "::error::chore(release) is release-bot's: merging its release pull request is what tags a release."
            exit 1
          fi
          echo "OK: $TITLE"