public AddPaymentMethodResponse AddPaymentMethod(
AddPaymentMethodRequest request, int accountId)
{
//this class allows a user to create and edit their payment details
var expiry = new DateTime(request.ExpiryYear, request.ExpiryMonth,
DateTime.DaysInMonth(request.ExpiryYear, request.ExpiryMonth));
//find the user and validate if they exist
var user = UserRepository.Find(accountId);
if (user == null)
{
return new AddPaymentMethodResponse
{
Message = $"Account {accountId} does not exist",
Success = false
}
}
;
//validate that the user must be activated in the system first
if (user.Status != Constants.UserActiveStatus)
{
return new AddPaymentMethodResponse
{
Message = "Only activated users can add payment methods",
Success = false
}
}
;
//validate that the card number entered and cvv is not empty
if (string.IsNullOrEmpty(request.CardNumber) ||
string.IsNullOrEmpty(request.CardVerificationValue))
{
return new AddPaymentMethodResponse
{
Message = "A credit card is required",
Success = false
}
}
;
request.CardNumber = request.CardNumber.Replace(" ", "");
//luhn check to validate that the entered card number is correct
var sumOfDigits = request.CardNumber.Where(
e => e >= '0' && e <= '9')
.Reverse()
.Select((e, i) => ((int)e - 48) * (i % 2 == 0 ? 1 : 2))
.Sum(e => e / 10 + e % 10);
//if luhn check fails
if (sumOfDigits % 10 != 0)
{
return new AddPaymentMethodResponse
{
Message = "The entered card number is invalid.",
Success = false
}
}
;
//if the card expiry exceeds the historic date
if (DateTime.Now > expiry)
{
return new AddPaymentMethodResponse
{
Message = "The entered credit card has expired.",
Success = false
}
}
;
//calculate the card type
string cardType;
switch (request.CardNumber.Substring(0, 1))
{
case "3":
cardType = "AMEX";
break;
case "4":
cardType = "Visa";
break;
case "5":
cardType = "Mastercard";
break;
default:
cardType = "Mastercard";
break;
}
try
{
//if an existing payment method exists update the old one
var existingPaymentMethod =
PaymentMethodRepository.Find(accountId);
if (existingPaymentMethod != null)
{
existingPaymentMethod.CardName = request.CardName;
existingPaymentMethod.CardNumber = request.CardNumber;
existingPaymentMethod.CardType = cardType;
existingPaymentMethod.ExpiryMonth = request.ExpiryMonth;
existingPaymentMethod.ExpiryYear = request.ExpiryYear;
existingPaymentMethod.CardVerificationValue =
request.CardVerificationValue;
PaymentMethodRepository.Update(existingPaymentMethod);
}
else
{
//otherwise create a new payment method
var payment = new PaymentMethod
{
AccountID = accountId,
CardNumber = request.CardNumber,
CardName = request.CardName,
CardType = cardType,
ExpiryMonth = request.ExpiryMonth,
ExpiryYear = request.ExpiryYear,
CardVerificationValue = request.CardVerificationValue
};
PaymentMethodRepository.Add(payment);
};
}
catch (Exception e)
{
return(new AddPaymentMethodResponse
{
Message = $"Error in updating payment method. Error: {e}",
Success = false
});
}
return(new AddPaymentMethodResponse
{
Success = true,
Message = "Payment method has been successfull added!"
});
}
