public static void LogSuccessfulTransaction(string cardNumber, DateTime transactionDate, decimal amount)
{
/*
* Task03
* We again use Repeatable read because we don't want someone to change the CardNumber while we are creating a new trasnaction history log for that card number
*/
TransactionScope tran = new TransactionScope(
TransactionScopeOption.Required,
new TransactionOptions()
{
IsolationLevel = IsolationLevel.RepeatableRead
});
using (tran)
{
using (ATMEntitiesModel context = new ATMEntitiesModel())
{
TransactionsHistory newLogEntry = new TransactionsHistory()
{
CardNumber = cardNumber,
TransactionDate = transactionDate,
Amount = amount
};
context.TransactionsHistories.Add(newLogEntry);
context.SaveChanges();
}
tran.Complete();
}
}
public static decimal RetreiveFunds(string cardNumber, string cardPin, decimal amount)
{
decimal remainingAmount = 0;
TransactionScope tran = new TransactionScope(
TransactionScopeOption.Required,
new TransactionOptions()
{
IsolationLevel = IsolationLevel.RepeatableRead
});
using (tran)
{
using (ATMEntitiesModel context = new ATMEntitiesModel())
{
var cardAccount = context.CardAccounts.FirstOrDefault(c => c.CardNumber == cardNumber && c.CardPIN == cardPin);
if (cardAccount == null)
{
throw new InvalidOperationException("Invalid Card Number of Card Pin");
}
decimal currentCardAmount = cardAccount.CardCash;
if (currentCardAmount < amount)
{
throw new InvalidOperationException("Insufficient Card Amount");
}
remainingAmount = cardAccount.CardCash - amount;
cardAccount.CardCash = remainingAmount;
context.SaveChanges();
}
tran.Complete();
}
return(remainingAmount);
}