gistfile1.rb

class SendList < ActiveRecord::Base

	belongs_to :destination, :polymorphic => true
	belongs_to :store
	has_many :send_list_items
	has_many :products, :through => :send_list_items

	after_initialize :setup_identifier

	def total_items
		self.send_list_items.inject(0){|result,item| result + item.product_total}
	end

	def shoes
		self.send_list_items.select{|i| i.product.shoe?}
	end

	def not_shoes
		self.send_list_items.select{|i| !i.product.shoe?}
	end

	def update_stock
		Product.transaction do
			self.products.each(&:update_stock_from_send_list)
		end
	end

	def setup_identifier
		unless self.identifier
			self.identifier = SendList.last.identifier.next
		end
	rescue
		self.identifier = "000001"
	end

end

gistfile2.rb

class SendList < ActiveRecord::Base

  # modules
  include Bentou::Models::Openable
  include Bentou::Models::AutoIdentifier
  include Bentou::Models::CategoryFiltrable 
  include Bentou::Models::ItemsManager  
  include Bentou::Models::ProductStockReflectable  
    
  belongs_to :destination, :polymorphic => true
  belongs_to :store
  has_many :send_list_items
  has_many :products, :through => :send_list_items

end