class LinkBar
  include Singleton
  
  def initialize
    @bars = Hash.new
    @bars.default = []
  end
  
  def register(linkbar_name, class_name, callback_method)
    @bars[linkbar_name] << {:class => class_name, :method => callback_method}
  end
  
  def query(linkbar_name)
    returning Array.new do |links|
      @bars[linkbar_name].each do |callback|
        links.concat callback[:class].send(callback[:method])
      end
    end
  end
 
  class << self
    def register(*args)
      instance.register(*args)
    end
    
    def query(*args)
      instance.query(*args)
    end
  end
end