name: Shadow Repo

on:
  push:
  pull_request:
    types: [opened]

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}-${{ github.event_name }}
  cancel-in-progress: true

jobs:
  build:
    name: Build
    runs-on: ubuntu-latest
    if: github.event_name == 'push'
    steps:
      - uses: actions/checkout@v3
      - uses: actions/setup-node@v3
        with:
          node-version-file: .nvmrc
          cache: npm
      - run: npm ci
      - run: npm run build-prod
      - run: tar cf site.tar _site
      - uses: actions/upload-artifact@v2
        with:
          name: site
          path: site.tar

  diff-link:
    name: Comment
    runs-on: ubuntu-latest
    if: github.event_name == 'pull_request' && github.event.action == 'opened'
    steps:
      - uses: peter-evans/create-or-update-comment@v3
        with:
          issue-number: ${{ github.event.number }}
          body: |
            View diff of compiled files (may take a few minutes): https://github.com/${{ vars.SHADOW_OWNER }}/${{ vars.SHADOW_REPO }}/compare/${{ github.event.pull_request.base.ref }}..${{ github.event.pull_request.head.ref }}