class Preview
  include Mongoid::Document
  include Mongoid::Timestamps

  field :object, :type => Hash
  field :preview_at_link
  field :expired_at , :type => DateTime
  field :link_args, :type => Array
  field :object_class_type
  
  def get_arg_hash
    object.slice(*link_args).inject({}){|la,(k,v)| la[k.to_sym] = v; la}
  end

  def get_preview_link
    ap = Rails.application.routes.url_helpers
    ap.send preview_at_link,({:id=>id,:preview=>true}.merge get_arg_hash)
    #func = eval("Rails.application.routes.url_helpers.#{preview_at_link}").send 
  end

  def get_virtual_object
    eval(self.object_class_type).new object
  end

end