name: Deploy main to GitHub Pages (stable)

on:
  push:
    branches: [main]
  workflow_dispatch:

permissions:
  contents: write


jobs:
  deploy-main-pages:
    if: ${{ env.ENABLE_DEPLOY == 'true' && env.ACT != 'true' }}
    runs-on: ubuntu-latest

    steps:
      - name: Checkout (main)
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Setup Python
        uses: actions/setup-python@v5
        with:
          python-version: "3.13"
          cache: "pip"
          cache-dependency-path: mkdocs/requirements.txt

      - name: Install dependencies
        run: |
          set -euo pipefail
          pip install -r mkdocs/requirements.txt

      - name: Build (MKDOCS_STRICT)
        run: |
          set -euo pipefail

          MKDOCS_STRICT="${MKDOCS_STRICT:-true}"
          STRICT_FLAG=""
          if [ "${MKDOCS_STRICT}" = "true" ]; then
            STRICT_FLAG="--strict"
          fi

          OFFLINE=true mkdocs build ${STRICT_FLAG} -f mkdocs/mkdocs.yml -d site_build

      - name: Checkout gh-pages branch
        run: |
          set -euo pipefail
          git fetch origin gh-pages:gh-pages || true
          if git show-ref --verify --quiet refs/heads/gh-pages; then
            git switch gh-pages
          else
            git switch --orphan gh-pages
            rm -rf ./*
            git config user.name "github-actions[bot]"
            git config user.email "github-actions[bot]@users.noreply.github.com"
            git commit --allow-empty -m "Initialize gh-pages"
          fi

      - name: Publish stable site to root (preserve rc/)
        run: |
          set -euo pipefail

          mkdir -p _keep
          if [ -d rc ]; then cp -a rc _keep/; fi

          rm -rf ./*
          if [ -d _keep/rc ]; then mv _keep/rc ./rc; fi
          rm -rf _keep

          cp -a ../site_build/. .

          git add -A
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"
          git commit -m "Deploy stable site from main" || echo "No changes to commit"
          git push origin gh-pages