public OrderCreationFacade(IMongoCollection <Order> collection, Func <OrderNumbersQuery> orderNumbersQuery, OrderPriceCalculationFacade orderPriceCalculationFacade, IPublisher <OrderCreated> orderCreatedPublisher, IDateTimeProvider dateTimeProvider, IEventsApi eventsApi)
{
this.collection = collection;
this.orderNumbersQuery = orderNumbersQuery;
this.orderPriceCalculationFacade = orderPriceCalculationFacade;
this.orderCreatedPublisher = orderCreatedPublisher;
this.dateTimeProvider = dateTimeProvider;
this.eventsApi = eventsApi;
}
public async Task ApplyDiscount(EventDTO eventData, CalculateOrderDTO order, List <PriceDataDTO> orderItemPrices, bool invalidateDiscountCoupon)
{
// get discount code
var discountCode = await discountCodeCollection.FindByIdAsync(order.DiscountCode);
if (discountCode == null || discountCode.ExpirationDate < DateTime.UtcNow || discountCode.ClaimedDate != null)
{
throw new InvalidDiscountCodeException();
}
// apply to products
for (int i = 0; i < order.OrderItems.Count; i++)
{
var orderItem = order.OrderItems[i];
var orderItemPrice = orderItemPrices[i];
// try to find an applicable rule
var rule = discountCode.Rules.FirstOrDefault(r => r.ApplicableSku.Contains(orderItem.Sku));
if (rule != null)
{
// apply the rule
var applicableAmount = Math.Min(orderItem.Amount, rule.MaxAmount);
var discountPrice = CalculateDiscountPrice(rule, orderItemPrice);
// add the discount order line
order.OrderItems.Add(new CalculateOrderItemDTO()
{
Sku = Constants.DiscountSku,
Amount = applicableAmount
});
orderItemPrices.Add(new PriceDataDTO()
{
BasePrice = -discountPrice,
CurrencyCode = orderItemPrice.CurrencyCode,
Price = OrderPriceCalculationFacade.Round(-discountPrice * applicableAmount)
});
if (invalidateDiscountCoupon)
{
// claim discount code
await InvalidateDiscountCode(order);
}
return;
}
}
throw new InvalidDiscountCodeException();
}
private decimal CalculateDiscountPrice(DiscountCodeRule rule, PriceDataDTO orderItemPrice)
{
decimal discountPrice = 0;
if (rule.DiscountAmount != null)
{
discountPrice = rule.DiscountAmount.Value;
}
else if (rule.DiscountPercent != null)
{
discountPrice = OrderPriceCalculationFacade.Round(orderItemPrice.BasePrice * rule.DiscountPercent.Value / 100m);
}
return(discountPrice);
}