name: Build and Publish to PyPI

on:
  workflow_dispatch:
    inputs:
      source_ref:
        description: 'Existing release tag to publish (for example v4.10.11)'
        required: true
        type: string
  release:
    types: [published]

jobs:
  build-and-publish:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      id-token: write  # Required for trusted publishing to PyPI

    steps:
      - name: Checkout code
        uses: actions/checkout@v4
        with:
          ref: ${{ inputs.source_ref || github.sha }}
          fetch-depth: 0
          persist-credentials: false

      - name: Validate release source and version
        env:
          RELEASE_TAG: ${{ inputs.source_ref || github.event.release.tag_name }}
        run: |
          python3 - <<'PY'
          import os
          import re
          import subprocess
          import tomllib
          from pathlib import Path

          tag = os.environ['RELEASE_TAG']
          if not re.fullmatch(r'v[0-9]+\.[0-9]+\.[0-9]+(?:-(?:alpha|beta|rc)\.[0-9]+)?', tag):
              raise SystemExit('source_ref must be an existing release tag: vX.Y.Z or vX.Y.Z-beta.N')
          def revision(ref):
              return subprocess.check_output(['git', 'rev-parse', '--verify', ref], text=True).strip()
          if revision('HEAD') != revision(f'refs/tags/{tag}^{{}}'):
              raise SystemExit('Checked-out commit does not match the release tag')
          version = tomllib.loads(Path('pyproject.toml').read_text())['project']['version']
          if version != tag[1:]:
              raise SystemExit(f'Package version {version} does not match tag {tag}')
          print(f'Validated {tag} at {revision("HEAD")} (package {version})')
          PY

      - name: Set up Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '22'

      - name: Build frontend
        run: |
          cd web
          # Match the archive/Docker npm path; npm ci rejects older tags' stale npm lockfiles.
          npm install --include=optional
          npm run build
          mkdir -p ../src/langbot/web/dist
          cp -r dist ../src/langbot/web/

      - name: Install the latest version of uv
        uses: astral-sh/setup-uv@v6
        with:
          version: "latest"

      - name: Build package
        run: |
          python3 scripts/stamp_build_revision.py
          uv build

      - name: Publish to PyPI
        run: |
          uv publish --token ${{ secrets.PYPI_TOKEN }}