protected void DisplayBalance(IReadOnlyCashTransaction balance)
{
Console.WriteLine("Machine Balance:");
var ordered = UnitedStatesTender.GetAllDefinedTenders().OrderByDescending(tender => tender.Value);
foreach (var bill in ordered)
{
Console.WriteLine($"${bill.Value} - {balance.BillCount(bill)}");
}
}
public IWithdrawalResult Withdraw(int amount, IAtmInventory inventory)
{
var withdrawTransaction = CashTransaction.Start();
var descendingUnitedStatesTenders = UnitedStatesTender.GetAllDefinedTenders().OrderByDescending(tender => tender.Value);
var transactionAmount = amount;
foreach (var tender in descendingUnitedStatesTenders)
{
var numberOfBills = transactionAmount / tender.Value;
if (numberOfBills > 0)
{
withdrawTransaction.Add(tender, numberOfBills);
transactionAmount = transactionAmount - tender.GetValue(numberOfBills);
}
if (transactionAmount == 0)
{
break;
}
if (transactionAmount < 0)
{
throw new ApplicationException($"transaction amount has gone below zero!");
}
}
// Does inventory support transaction
var isPossible = inventory.Withdraw(withdrawTransaction);
if (isPossible)
{
return(WithdrawalResult.CreateSuccessResult(withdrawTransaction));
}
else
{
return(WithdrawalResult.CreateFailureResult("insufficient funds", withdrawTransaction));
}
}