name: Documentation

on:
  push:
    branches: [ main ]

permissions:
  contents: write

jobs:
  docs:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@v2

    - name: Cache mdbook installation
      uses: actions/cache@v2
      with:
        path: ~/.cargo/bin/mdbook
        key: ${{ runner.os }}-mdbook

    - name: Cache mdbook-mermaid installation
      uses: actions/cache@v2
      with:
        path: ~/.cargo/bin/mdbook
        key: ${{ runner.os }}-mdbook-mermaid

    - name: Install mdBook if not installed already
      run: |
        if [ ! -f ~/.cargo/bin/mdbook ]; then
          cargo install mdbook
        fi

    - name: Install mdBook-mermaid if not installed already
      run: |
        if [ ! -f ~/.cargo/bin/mdbook-mermaid ]; then
          cargo install mdbook-mermaid
        fi

    - name: Cache mdBook build
      id: mdbook-build-cache
      uses: actions/cache@v3
      with:
        path: ./docs/book/
        key: ${{ runner.os }}-mdbook-${{ hashFiles('./docs/**') }}
        restore-keys: |
          ${{ runner.os }}-mdbook-

    - name: Build the book
      if: steps.mdbook-build-cache.outputs.cache-hit != 'true'
      run: mdbook build ./docs/

    - name: Deploy book to GitHub Pages
      uses: peaceiris/actions-gh-pages@v3
      with:
        github_token: ${{ secrets.GITHUB_TOKEN }}
        publish_dir: ./docs/book/