listing_page.rb

class ListingPage
  attr_reader :url

  def initialize(url)
    @url = url
  end

  def nodes
    nodes = []
    dom.at_css("#toc_rows").traverse do |node|
      nodes << something_node(node)               
    end
    nodes
  end
  
  def something_node(node)
    case 
    when node[:class] == "row"
      Listing.new(node)
    when node[:class]=="ban" && node.name == "h4" 
      DateBanner.new(node)
    end
  end

  def dom
    @dom ||= Nokogiri::HTML(open(url))
  end

end

class Node
  def initialize(node); @node = node; end
  def to_s; "<#{self.class.name}>"; end
end
class Listing < Node
  def initialize(node); super; end
end
class DateBanner < Node
  def initialize(node); super; end
end