public void Buy(string userName, int productId, int quantity)
{
if (quantity <= 0)
{
throw new InvalidOperationException("Quantity can't be less or equal 0");
}
lockService.Execute(() =>
{
try
{
var entities = GetAndCheckEntities(userName, productId);
User user = entities.Item1;
Product product = entities.Item2;
if (product.Quantity < quantity)
{
throw new ValidationException("Not enough product to buy");
}
float userDiscount = GetDiscount(productId);
decimal discountPrice = userDiscount != 0
? product.Cost - ((product.Cost / 100) * (decimal)userDiscount)
: product.Cost;
decimal amount = discountPrice * quantity;
if (user.Amount < amount)
{
throw new ValidationException("Not enough money to buy the product");
}
transactionsRepository.Add(new Transaction()
{
Username = user.Name,
ProductId = product.Id,
ProductName = product.Name,
Quantity = quantity,
Cost = product.Cost,
Discount = userDiscount,
SellCost = discountPrice,
Amount = amount
});
productsRepository.ChangeQuantity(productId, product.Quantity - quantity);
usersRepository.ChangeBalance(user.Name, user.Amount - amount);
}
catch (Exception ex) when(!(ex is ValidationException))
{
errorsRepository.Add(new TransactionError()
{
Date = environment.GetUtcNow(),
Description = ex.Message
});
throw;
}
});
}
public void Create(User user)
{
lockService.Execute(() =>
{
user.Assert(() => new ArgumentNullException("user"))
.Do(u => ValidateAndThrowIfErrors(u))
.Do(u => usersRepository.Add(u));
});
}
