module RSlow
  class HtmlResource < ParsableResource
    attr_accessor  :doc, :scripts, :stylesheets, :images

    def initialize(url)
      super
      @doc = Nokogiri::HTML(@contents)
      @scripts     = fetch_script_resources(".//script", 'src', JsResource)
      @stylesheets = fetch_stylesheet_resources(".//link[@rel]", 'href', CssResource)
      @images      = fetch_image_resources(".//img", 'src', Resource)
    end

    private

    def fetch_resources(xpath, url_attribute, klass)
      resources = []
      @doc.xpath(xpath).each do |elem|
        url = elem[url_attribute]
        res = klass.new(url, self) unless url.nil? || url.empty?
        resources << res
        @children << res
      end
      return resources
   end
end