public async Task <OrderPlaced> Handle(PlaceOrderCommand command)
{
var(clientId, offer) = CreateDomainModelFrom(command);
var currentOffer = await _calculatePrices.For(clientId, SalesChannel.OnlineSales, offer.ProductAmounts, offer.Currency);
if (!offer.Equals(currentOffer))
{
throw new DomainException();
}
var order = Order.FromOffer(offer);
await _orders.Save(order);
return(CreateEventFrom(clientId, order));
}
private static (ClientId, Offer) CreateDomainModelFrom(PlaceOrderCommand command) => (