ci.yml

on:
  push:
    branches:
      - main
  pull_request:
    branches:
      - main

name: Build and deploy sites

jobs:
  build:
    name: Build site and generate HTML
    runs-on: ubuntu-latest
    outputs:
      ref-url: ${{ steps.deploy.outputs.deploy-url }}

    steps:
      - name: Install deps for figures
        run: |
          sudo apt update && sudo apt install -y texlive-latex-base texlive-pictures texlive-luatex texlive-latex-extra fonts-firacode texlive-fonts-extra poppler-utils

      - name: Install elan
        run: |
          set -o pipefail
          curl -sSfL https://github.com/leanprover/elan/releases/download/v3.0.0/elan-x86_64-unknown-linux-gnu.tar.gz | tar xz
          ./elan-init -y --default-toolchain none
          echo "$HOME/.elan/bin" >> "$GITHUB_PATH"

      - uses: actions/checkout@v4

      - name: Lean Version
        run: |
          lean --version

      - name: Cache .lake
        uses: actions/cache@v3
        with:
          path: .lake
          key: ${{ runner.os }}-${{ hashFiles('lean-toolchain') }}-${{ hashFiles('lake-manifest.json') }}-${{ hashFiles('lakefile.lean') }}-${{ github.sha }}
          restore-keys: |
            ${{ runner.os }}-${{ hashFiles('lean-toolchain') }}-${{ hashFiles('lake-manifest.json') }}-${{ hashFiles('lakefile.lean') }}-${{ github.sha }}
            ${{ runner.os }}-${{ hashFiles('lean-toolchain') }}-${{ hashFiles('lake-manifest.json') }}-${{ hashFiles('lakefile.lean') }}
            ${{ runner.os }}-${{ hashFiles('lean-toolchain') }}-${{ hashFiles('lake-manifest.json') }}-
            ${{ runner.os }}-${{ hashFiles('lean-toolchain') }}-

      - name: Build
        run: |
          lake build

      - name: Generate HTML
        run: |
          lake exe generate-manual --depth 2

      - name: Offline link checker
        uses: lycheeverse/lychee-action@v1.9.0
        with:
          args: --base './_out/html-multi/' --no-progress --offline './_out/html-multi/**/*.html'

      # deploy-alias computes a stable, but difficult-to-guess, URL component
      # for the PR preview. This is so we can have a stable name to use for
      # feedback on draft material, but at the same time we avoid having
      # something guessable by outsiders.
      #
      # SALT is a repository secret that contains some arbitrary string.
      - id: deploy-alias
        uses: actions/github-script@v7
        name: Compute Alias
        with:
          script: |
            var crypto = require('crypto');
            if (process.env.PR && process.env.SALT) {
                var hash = crypto.createHash('sha256')
                  .update(process.env.PR)
                  .update(process.env.SALT)
                  .digest('hex')
                  .slice(0,8);
                return `pr-${process.env.PR}-${hash}`
            }
        env:
          PR: ${{ github.event.number }}
          SALT: ${{ secrets.SALT }}

        # deploy-info computes metadata that's shown in the Netlify interface
        # about the deployment (for non-PR deploys)
      - id: deploy-info
        name: Compute Deployment Metadata
        if: github.event_name != 'pull_request'
        run: |
          set -e
          echo "message=$(git log -1 --pretty=format:"%s")" >> "$GITHUB_OUTPUT"

      - name: Deploy
        id: deploy
        uses: nwtgck/actions-netlify@v2.0
        with:
          publish-dir: _out/html-multi
          production-branch: main
          github-token: ${{ secrets.GITHUB_TOKEN }}
          deploy-message: |
            ${{ github.event_name == 'pull_request' && format('pr#{0}: {1}', github.event.number, github.event.pull_request.title) || format('ref/{0}: {1}', github.ref_name, steps.deploy-info.outputs.message) }}
          alias: ${{ steps.deploy-alias.outputs.result }}
          enable-commit-comment: false
          enable-pull-request-comment: false
          github-deployment-environment: |
            ${{ github.event_name == 'pull_request' && format('lean-ref-pr-#{0}', github.event.number) || 'lean-ref' }}
          fails-without-credentials: true
        env:
          NETLIFY_AUTH_TOKEN: ${{ secrets.NETLIFY_AUTH_TOKEN }}
          NETLIFY_SITE_ID: "447031bf-9a96-4cee-831b-1f73599a7cb2"


  check-links:
    name: Check links
    runs-on: ubuntu-latest
    needs: [build]
    steps:
      - uses: actions/checkout@v4
        with:
          sparse-checkout: |
            .skip-link-check

      - name: Online link checker
        uses: filiph/linkcheck@2.0.23
        continue-on-error: true
        with:
          arguments: --skip-file .skip-link-check -e ${{ needs.build.outputs.ref-url }}