class Asciidoctor::SyntaxHighlighter::PrettifyAdapter

def docinfo location, doc, opts
  base_url = doc.attr 'prettifydir', %(#{opts[:cdn_base_url]}/prettify/r298)
  if location == :head
    prettify_theme_url = ((prettify_theme = doc.attr 'prettify-theme', 'prettify').start_with? 'http://', 'https://') ? prettify_theme : %(#{base_url}/#{prettify_theme}.min.css)
    %(<link rel="stylesheet" href="#{prettify_theme_url}"#{opts[:self_closing_tag_slash]}>)
  else # :footer
    %(<script src="#{base_url}/run_prettify.min.js"></script>)
  end
end