package_generator_service.rb

# -*- encoding : utf-8 -*-
# 下单成功之后初始化Package过程
# 1. 初始化Package
# 2. 初始化Package Item
# 3. 实时同步库存数量
class PackageGenerator
  attr_accessor :order, :package, :pickup_customer

  def initialize(order, pickup_customer)
    @order = order
    @pickup_customer = pickup_customer
  end

  def run
    generate_package
    generate_package_items
    sync_warehouse_stock_quantity
    package
  end

  private

  def generate_package
    @package ||= order.packages.create!(:warehouse_id => get_warehouse_id, :state => get_init_state)
  end

  def get_init_state
    return Package::STATE_VALUES[:awaiting_process] if pickup_customer || order.metro_pickup?
    return Package::STATE_VALUES[:awaiting_stock]
  end

  def get_warehouse_id
    return Warehouse::CENTERS[:Mtl] if order.metro_pickup?
    return pickup_customer.scm_distribution_center_id if pickup_customer
    return nil
  end

  def generate_package_items
    order.order_items.includes(:product).each do |order_item|
      if product = order_item.product
        if product.is_value_pack?
          add_virtual_product_to_package_item(order_item, package, product)
        else
          add_product_to_package_item(order_item, package, product)
        end
      end
    end
  end

  def add_product_to_package_item(order_item, package, product)
    exist_package_item = package.items.where(:product_id => product.id).first
    if exist_package_item
      exist_package_item.update_column(:quantity, exist_package_item.quantity.to_i + order_item.quantity)
      exist_package_item
    else
      package.items.create!(
        :product_id => product.id,
        :order_id => package.order_id,
        :order_item_id => order_item.id,
        :quantity => order_item.quantity
      )
    end
  end

  def add_virtual_product_to_package_item(order_item, package, product)
    product.virtual_product_items.each do |virtual_product_item|
      exist_package_item = package.items.where(:product_id => virtual_product_item.product_id).first
      if exist_package_item
        exist_package_item.update_column(:quantity, exist_package_item.quantity.to_i + virtual_product_item.quantity * order_item.quantity)
        exist_package_item
      else
        package.items.create!(
          :product_id => virtual_product_item.product_id,
          :order_id => package.order_id,
          :order_item_id => order_item.id,
          :quantity => virtual_product_item.quantity * order_item.quantity
        )
      end
    end
  end

  def sync_warehouse_stock_quantity
    StockUpdater::PackageItemsChanging.update(package) if package.processing_stock?
  end
end