#---
# Excerpted from "Agile Web Development with Rails, 3rd Ed.",
# published by The Pragmatic Bookshelf.
# Copyrights apply to this code. It may not be used to create training material, 
# courses, books, articles, and the like. Contact us if you are in doubt.
# We make no guarantees that this code is fit for any purpose. 
# Visit http://www.pragmaticprogrammer.com/titles/rails3 for more book information.
#---
class Cart
  attr_reader :items   
  
  def initialize
    @items = []
  end
  
  
  def add_product(product)
    current_item = @items.find {|item| item.product == product}
    if current_item
      current_item.increment_quantity
    else
      @items << CartItem.new(product)
    end
  end
  
end