##
# Order Item 是订单项。

module Unidom
  module Order

    class OrderItem < ApplicationRecord

      self.table_name = 'unidom_order_items'

      include Unidom::Common::Concerns::ModelExtension
      include Unidom::Order::Concerns::AsAdjusted

      #validates :ordinal,         presence: true, numericality: { only_integer: true, greater_than: 0, less_than: 1_000_000_000 }
      validates :unit_price,      presence: true, numericality: { greater_than_or_equal_to: 0, less_than_or_equal_to: 1_000_000_000 }
      validates :quantity,        presence: true, numericality: { greater_than:             0, less_than_or_equal_to: 1_000_000_000 }
      validates :purchase_amount, presence: true, numericality: { greater_than_or_equal_to: 0, less_than_or_equal_to: 1_000_000_000 }
      validates :subtotal_amount, presence: true, numericality: { greater_than_or_equal_to: 0, less_than_or_equal_to: 1_000_000_000 }

      belongs_to :order,   class_name:  'Unidom::Order::Order'
      belongs_to :ordered, polymorphic: true
      belongs_to :placer,  polymorphic: true

      scope :order_is,   ->(order)   { where order:   order   }
      scope :ordered_is, ->(ordered) { where ordered: ordered }
      scope :placed_by,  ->(placer)  { where placer:  placer  }

      ##
      # 订购商品 ordered ，放入订单 of 。订购者为 by ，缺省为订单的下单者。单价为 unit_price ，缺省值为 0 。数量为 quantity ，缺省值为 1。如：
      # Unidom::Order::OrderItem.order! coca_cola, of: order, by: current_person, unit_price: 3.50, quantity: 2
      def self.order!(ordered, of: nil, by: of.placer, unit_price: 0, quantity: 1)
        item = of.items.ordered_is(ordered).placed_by(by).valid_at.alive.first
        if item.present?
          item.quantity        += quantity
          item.unit_price      =  unit_price
          item.purchase_amount =  item.unit_price*item.quantity
          item.subtotal_amount =  item.purchase_amount+item.adjustments.valid_at.alive.sum(:amount).to_f
          item.save!
        else
          ordinal = 1+of.items.valid_at.alive.maximum(:ordinal).to_i
          of.items.create! ordered: ordered, placer: by, ordinal: ordinal, quantity: quantity, unit_price: unit_price, purchase_amount: unit_price*quantity, subtotal_amount: unit_price*quantity, opened_at: Time.now
        end
      end

    end unless Unidom::Common::Neglection.namespace_neglected? 'Unidom::Order::OrderItem'

  end
end