83 lines
3.4 KiB
C#

using Microsoft.eShopOnContainers.Services.Ordering.Domain.AggregatesModel.BuyerAggregate;
using Microsoft.eShopOnContainers.Services.Ordering.Domain.Seedwork;
using System;
using System.Collections.Generic;
using System.Linq;
namespace Microsoft.eShopOnContainers.Services.Ordering.Domain.AggregatesModel.OrderAggregate
{
public class Order
: Entity
{
// DDD Patterns comment
// Using private fields, allowed since EF Core 1.1, is a much better encapsulation
// aligned with DDD Aggregates and Domain Entities (Instead of properties and property collections)
private DateTime _orderDate;
public Address Address { get; private set; }
public Buyer Buyer { get; private set; }
private int _buyerId;
public OrderStatus OrderStatus { get; private set; }
private int _orderStatusId;
// DDD Patterns comment
// Using a private collection field, better for DDD Aggregate's encapsulation
// so OrderItems cannot be added from "outside the AggregateRoot" directly to the collection,
// but only through the method OrderAggrergateRoot.AddOrderItem() which includes behaviour.
private readonly List<OrderItem> _orderItems;
public IEnumerable<OrderItem> OrderItems => _orderItems.AsReadOnly();
// Using List<>.AsReadOnly()
// This will create a read only wrapper around the private list so is protected against "external updates".
// It's much cheaper than .ToList() because it will not have to copy all items in a new collection. (Just one heap alloc for the wrapper instance)
//https://msdn.microsoft.com/en-us/library/e78dcd75(v=vs.110).aspx
public PaymentMethod PaymentMethod { get; private set; }
private int _paymentMethodId;
protected Order() { }
public Order(int buyerId, int paymentMethodId, Address address)
{
_orderItems = new List<OrderItem>();
_buyerId = buyerId;
_paymentMethodId = paymentMethodId;
_orderStatusId = OrderStatus.InProcess.Id;
_orderDate = DateTime.UtcNow;
Address = address;
}
// DDD Patterns comment
// This Order AggregateRoot's method "AddOrderitem()" should be the only way to add Items to the Order,
// so any behavior (discounts, etc.) and validations are controlled by the AggregateRoot
// in order to maintain consistency between the whole Aggregate.
public void AddOrderItem(int productId, string productName, decimal unitPrice, decimal discount, string pictureUrl, int units = 1)
{
var existingOrderForProduct = _orderItems.Where(o => o.ProductId == productId)
.SingleOrDefault();
if (existingOrderForProduct != null)
{
//if previous line exist modify it with higher discount and units..
if (discount > existingOrderForProduct.GetCurrentDiscount())
{
existingOrderForProduct.SetNewDiscount(discount);
existingOrderForProduct.AddUnits(units);
}
}
else
{
//add validated new order item
var orderItem = new OrderItem(productId, productName, unitPrice, discount, pictureUrl, units);
_orderItems.Add(orderItem);
}
}
}
}