name: Deploy Docs

on:
  push:
    branches:
      - 'main'
  # Allows running the action manually.
  workflow_dispatch:

env:
  CARGO_TERM_COLOR: always
  RUSTDOCFLAGS: --html-in-header header.html
  # If nightly is breaking CI, modify this variable to target a specific nightly version.
  NIGHTLY_TOOLCHAIN: nightly

# Sets the permissions to allow deploying to Github pages.
permissions:
  contents: read
  pages: write
  id-token: write

# Only allow one deployment to run at a time, however it will not cancel in-progress runs.
concurrency:
  group: "pages"
  cancel-in-progress: false

jobs:
  build-and-deploy:
    runs-on: ubuntu-latest
    # Only run this job when on the main Bevy repository. Without this, it would also run on forks
    # where developers work on the main branch but have not enabled Github Pages.
    if: ${{ github.repository == 'bevyengine/bevy' }}
    environment:
      name: github-pages
      url: ${{ steps.deployment.outputs.page_url }}
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - uses: dtolnay/rust-toolchain@master
        with:
          toolchain: ${{ env.NIGHTLY_TOOLCHAIN }}

      - name: Install Linux dependencies
        uses: ./.github/actions/install-linux-deps
        with:
          wayland: true
          xkb: true

      #  This does the following:
      #   - Replaces the docs icon with one that clearly denotes it's not the released package on crates.io
      #   - Adds a meta tag that forces Google not to index any page on the site.
      - name: Pre-docs-build
        run: |
          sed -i.bak "s/icon.png/icon-docs-dev.png/" src/lib.rs
          echo "<meta name=\"robots\" content=\"noindex\">" > header.html

      - name: Build docs
        env:
          # needs to be in sync with [package.metadata.docs.rs]
          RUSTFLAGS: --cfg docsrs_dep
          RUSTDOCFLAGS: -Zunstable-options --cfg=docsrs --generate-link-to-definition
        run: |
          cargo doc \
            -Zunstable-options \
            -Zrustdoc-scrape-examples \
            --all-features \
            --workspace \
            --no-deps \
            --document-private-items \
            --exclude ci \
            --exclude errors \
            --exclude bevy_mobile_example \
            --exclude build-wasm-example \
            --exclude build-templated-pages \
            --exclude example-showcase

      #  This adds the following:
      #   - A top level redirect to the bevy crate documentation
      #   - A CNAME file for redirecting the docs domain to the API reference
      #   - A robots.txt file to forbid any crawling of the site (to defer to the docs.rs site on search engines).
      - name: Finalize documentation
        run: |
          echo "<meta http-equiv=\"refresh\" content=\"0; url=bevy/index.html\">" > target/doc/index.html
          echo "dev-docs.bevyengine.org" > target/doc/CNAME
          echo $'User-Agent: *\nDisallow: /' > target/doc/robots.txt
          rm target/doc/.lock

      - name: Upload site artifact
        uses: actions/upload-pages-artifact@v3
        with:
          path: target/doc

      - name: Deploy to Github Pages
        id: deployment
        uses: actions/deploy-pages@v4