name: Build Eleventy

on:
  push:
    branches:
      - main
    paths-ignore:
      - 'maintenance/**'
      - 'README.md'
  pull_request:
    paths-ignore:
      - 'maintenance/**'
      - 'README.md'
  workflow_dispatch:

jobs:
  build:
    runs-on: arch-linux

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Set up Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '24'

      - name: Install dependencies
        run: npm ci

      - name: Build site
        run: npm run build

      - name: Publish to forgejo-pages branch
        if: github.ref == 'refs/heads/main'
        env:
          TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          git config --global user.name "Forgejo Actions"
          git config --global user.email "actions@localhost"

          # Clone target branch
          git clone \
            "https://oauth2:${TOKEN}@${{ github.server_url#https:// }}/${{ github.repository }}.git" \
            deploy

          cd deploy

          # Switch to forgejo-pages branch, create if missing
          if git show-ref --verify --quiet refs/heads/forgejo-pages; then
            git checkout forgejo-pages
          else
            git checkout --orphan forgejo-pages
            git rm -rf .
          fi

          # Remove old contents
          find . -mindepth 1 -maxdepth 1 \
            ! -name '.git' \
            -exec rm -rf {} +

          # Copy new build output
          cp -r ../docs/. .

          # Commit and push if there are changes
          git add .
          if ! git diff --cached --quiet; then
            git commit -m "Deploy from ${GITHUB_SHA}"
            git push origin forgejo-pages
          fi