name: documentation cleanup
on:
  schedule:
    - cron: '0 1 * * SUN'

jobs:
  docs-cleanup:
    runs-on: ubuntu-latest
    if: github.repository == 'cvc5/cvc5'
    steps:
      - name: Install Packages
        run: |
          sudo apt-get update
          sudo apt-get install -y python3 python3-jinja2

      - name: Setup Deploy Key
        env:
            SSH_AUTH_SOCK: /tmp/ssh_agent.sock
        run: |
            ssh-agent -a $SSH_AUTH_SOCK > /dev/null
            ssh-add - <<< "${{ secrets.CVC5_DOCS_TOKEN }}"

      - name: Clone docs repo
        env:
            SSH_AUTH_SOCK: /tmp/ssh_agent.sock
        run: |
          git config --global user.email "docbot@cvc5"
          git config --global user.name "DocBot"
          git clone git@github.com:cvc5/docs-ci.git target/
      
      - name: Remove stale docs
        run: |
          cd target
          for file in `find ./ -maxdepth 1 -name "docs-*"`; do
            mod=`git log -1 HEAD --pretty="%ci" $file`
            touch -d "$mod" $file
          done
          find ./ -maxdepth 1 -name "docs-*" -mtime +7 -exec git rm -r {} +
          find ./ -maxdepth 1 -name "docs-*" -xtype l -exec git rm {} +
          git commit -m "Prune docs" || echo "Nothing to prune"

      - name: Squash old commits
        env:
            SSH_AUTH_SOCK: /tmp/ssh_agent.sock
        run: |
          cd target
          first=`git rev-list --max-parents=0 HEAD`
          last=`git rev-list --until=1.month.ago -n1 HEAD`
          if [ -n "$last" ]; then
            git checkout $last
            ts=`git log -1 --format=%ct`
            git reset --soft $first
            if git diff --cached --exit-code
            then
              echo "Nothing to squash"
            else
              git commit -m "Squash old history" --date=$ts
            fi
            git cherry-pick $last..main
          fi
      
      - name: Push
        env:
            SSH_AUTH_SOCK: /tmp/ssh_agent.sock
        run: |
          cd target

          python3 genindex.py
          git add README.md
          if git diff --cached --exit-code
          then
            echo "Nothing changed"
          else
            git commit -m "Update README.md"
          fi

          git push -f origin HEAD:main