class Item < ActiveRecord::Base
  belongs_to :unit
  has_many :multi_media_descriptions
  belongs_to :sub_category
  belongs_to :supplier
  belongs_to :brand
  belongs_to :delivery_time_estimation
  has_and_belongs_to_many :item_groups,                                                       :join_table => 'item_item_groups'

  validates_presence_of :name, :description, :list_price, :current_input_price, :tags, :unit_id, :code, :sub_category_id, :weight, :supplier_id

  def self.items_to_order
  	items_raw = Item.find_by_sql(%Q{
  		select s.id as supplier_id, i.code as code, i.name as name, sum(iic.count) amount, i.current_input_price
  		from carts c
  		left join item_in_carts iic on iic.cart_id = c.id
  		left join items i on i.id = iic.item_id
  		left join suppliers s on i.supplier_id = s.id
  		where c.confirmed and not (c.packed or c.delivered)
  		group by s.id, i.name, i.code, i.current_input_price
  		order by s.name, amount desc;
    })

    items_sorted = {}
    suppliers_sorted = {}

    items_raw.each do |item|
      items_sorted[item.supplier_id] ||= []
      suppliers_sorted[item.supplier_id] ||= item.supplier
      items_sorted[item.supplier_id] << item
    end

    report_items = []

    complete_sum = 0

    suppliers_sorted.each_pair do |key, value|
      rep_sec = OpenStruct.new # report section
      rep_sec.supplier = value
      rep_sec.items = items_sorted[key]
      rep_sec.sum_amount = rep_sec.items.reduce(0) do |sum, item|
        sum + (item.current_input_price * item.amount)
      end
      complete_sum += rep_sec.sum_amount

      report_items << rep_sec
    end

    full_report = OpenStruct.new
    full_report.sections = report_items
    full_report.full_sum = complete_sum

    return full_report
  end


end