name: Documentation and GitHub Pages

on:
  pull_request:
  push:
    branches:
      - main
    tags:
      - '*'

  # Allows you to run this workflow manually from the Actions tab
  workflow_dispatch:

env:
  # Required to make some things output color
  TERM: ansi
  # Publishing to my nix binary cache
  ATTIC_TOKEN: ${{ secrets.ATTIC_TOKEN }}
  # conduwuit.cachix.org
  CACHIX_AUTH_TOKEN: ${{ secrets.CACHIX_AUTH_TOKEN }}
  # Custom nix binary cache if fork is being used
  ATTIC_ENDPOINT: ${{ vars.ATTIC_ENDPOINT }}
  ATTIC_PUBLIC_KEY: ${{ vars.ATTIC_PUBLIC_KEY }}
  # Get error output from nix that we can actually use, and use our binary caches for the earlier CI steps
  NIX_CONFIG: |
    show-trace = true
    extra-substituters = https://attic.kennel.juneis.dog/conduit https://attic.kennel.juneis.dog/conduwuit https://cache.lix.systems https://conduwuit.cachix.org
    extra-trusted-public-keys = conduit:eEKoUwlQGDdYmAI/Q/0slVlegqh/QmAvQd7HBSm21Wk= conduwuit:BbycGUgTISsltcmH0qNjFR9dbrQNYgdIAcmViSGoVTE= cache.lix.systems:aBnZUw8zA7H35Cz2RyKFVs3H4PlGTLawyY5KRbvJR8o= conduwuit.cachix.org-1:MFRm6jcnfTf0jSAbmvLfhO3KBMt4px+1xaereWXp8Xg=

# Allow only one concurrent deployment, skipping runs queued between the run in-progress and latest queued.
# However, do NOT cancel in-progress runs as we want to allow these production deployments to complete.
concurrency:
  group: "pages"
  cancel-in-progress: false

jobs:
  docs:
    name: Documentation and GitHub Pages
    runs-on: ubuntu-latest

    permissions:
      pages: write
      id-token: write

    environment:
      name: github-pages
      url: ${{ steps.deployment.outputs.page_url }}

    steps:
      - name: Free Disk Space (Ubuntu)
        uses: jlumbroso/free-disk-space@main

      - name: Sync repository
        uses: actions/checkout@v4

      - name: Setup GitHub Pages
        if: github.event_name != 'pull_request'
        uses: actions/configure-pages@v5

      - uses: nixbuild/nix-quick-install-action@v28

      - name: Restore and cache Nix store
        uses: nix-community/cache-nix-action@v5.1.0
        with:
          # restore and save a cache using this key
          primary-key: nix-${{ runner.os }}-${{ hashFiles('**/*.nix', '**/.lock') }}
          # if there's no cache hit, restore a cache by this prefix
          restore-prefixes-first-match: nix-${{ runner.os }}-
          # collect garbage until Nix store size (in bytes) is at most this number
          # before trying to save a new cache
          gc-max-store-size-linux: 2073741824
          # do purge caches
          purge: true
          # purge all versions of the cache
          purge-prefixes: nix-${{ runner.os }}-
          # created more than this number of seconds ago relative to the start of the `Post Restore` phase
          purge-last-accessed: 86400
          # except the version with the `primary-key`, if it exists
          purge-primary-key: never
          # always save the cache
          save-always: true

      - name: Enable Cachix binary cache
        run: |
            nix profile install nixpkgs#cachix
            cachix use crane
            cachix use nix-community

      - name: Apply Nix binary cache configuration
        run: |
            sudo tee -a "${XDG_CONFIG_HOME:-$HOME/.config}/nix/nix.conf" > /dev/null <<EOF
            extra-substituters = https://attic.kennel.juneis.dog/conduit https://attic.kennel.juneis.dog/conduwuit https://cache.lix.systems https://conduwuit.cachix.org
            extra-trusted-public-keys = conduit:eEKoUwlQGDdYmAI/Q/0slVlegqh/QmAvQd7HBSm21Wk= conduwuit:BbycGUgTISsltcmH0qNjFR9dbrQNYgdIAcmViSGoVTE= cache.lix.systems:aBnZUw8zA7H35Cz2RyKFVs3H4PlGTLawyY5KRbvJR8o= conduwuit.cachix.org-1:MFRm6jcnfTf0jSAbmvLfhO3KBMt4px+1xaereWXp8Xg=
            EOF

      - name: Use alternative Nix binary caches if specified
        if: ${{ (env.ATTIC_ENDPOINT != '') && (env.ATTIC_PUBLIC_KEY != '') }}
        run: |
            sudo tee -a "${XDG_CONFIG_HOME:-$HOME/.config}/nix/nix.conf" > /dev/null <<EOF
            extra-substituters = ${{ env.ATTIC_ENDPOINT }}
            extra-trusted-public-keys = ${{ env.ATTIC_PUBLIC_KEY }}
            EOF

      - name: Prepare build environment
        run: |
            echo 'source $HOME/.nix-profile/share/nix-direnv/direnvrc' > "$HOME/.direnvrc"
            nix profile install --inputs-from . nixpkgs#direnv nixpkgs#nix-direnv
            direnv allow
            nix develop --command true

      - name: Cache CI dependencies
        run: |
            bin/nix-build-and-cache ci

      - name: Run lychee and markdownlint
        run: |
            direnv exec . engage just lints lychee
            direnv exec . engage just lints markdownlint

      - name: Build documentation (book)
        run: |
            bin/nix-build-and-cache just .#book

            cp -r --dereference result public

      - name: Upload generated documentation (book) as normal artifact
        uses: actions/upload-artifact@v4
        with:
          name: public
          path: public
          if-no-files-found: error
          # don't compress again
          compression-level: 0

      - name: Upload generated documentation (book) as GitHub Pages artifact
        if: github.event_name != 'pull_request'
        uses: actions/upload-pages-artifact@v3
        with:
          path: public

      - name: Deploy to GitHub Pages
        if: github.event_name != 'pull_request'
        id: deployment
        uses: actions/deploy-pages@v4