public void ConstructATransaction()
{
// arrange
var expectedFiveDollarBills = 3;
var expectedOneDollarBills = 2;
var expectedAmount = 17;
CashTransaction testTransaction = CashTransaction.Start();
// act
testTransaction
.Add(UnitedStatesTender.FiveDollar, expectedFiveDollarBills)
.Add(UnitedStatesTender.OneDollar, expectedOneDollarBills);
// assert
Assert.Equal <int>(expectedAmount, testTransaction.TotalAmount);
Assert.Equal <int>(expectedFiveDollarBills, testTransaction.BillCount(UnitedStatesTender.FiveDollar));
Assert.Equal <int>(expectedOneDollarBills, testTransaction.BillCount(UnitedStatesTender.OneDollar));
}
public void GivenEmptyInventoryWhenRestockedThenBalanceIsExpected()
{
// Arrange
var sut = new AtmInventory();
var expectedInventory = CashTransaction.Start();
expectedInventory.Add(UnitedStatesTender.FiveDollar, 10);
expectedInventory.Add(UnitedStatesTender.OneDollar, 10);
// Act
sut.ResetInventory(expectedInventory);
// Assert
var actual = sut.MachineBalance();
Assert.Equal <int>(60, actual.TotalAmount);
Assert.Equal <int>(10, actual.BillCount(UnitedStatesTender.FiveDollar));
Assert.Equal <int>(10, actual.BillCount(UnitedStatesTender.OneDollar));
}
public void GivenStockedInventoryWhenRequestingInventoryByBillsThenOnlyBillsThatAreReuestedAreReturned()
{
// Arrange
var sut = new AtmInventory();
var expectedInventory = CashTransaction.Start();
expectedInventory.Add(UnitedStatesTender.TenDollar, 1000);
expectedInventory.Add(UnitedStatesTender.FiveDollar, 100);
expectedInventory.Add(UnitedStatesTender.OneDollar, 10);
sut.ResetInventory(expectedInventory);
var billsToGet = new List <UnitedStatesTender>();
billsToGet.Add(UnitedStatesTender.OneDollar);
billsToGet.Add(UnitedStatesTender.TenDollar);
// Act
var actual = sut.InventoryByBills(billsToGet);
// Assert
Assert.Equal <int>(1000, actual.BillCount(UnitedStatesTender.TenDollar));
Assert.Equal <int>(0, actual.BillCount(UnitedStatesTender.FiveDollar));
Assert.Equal <int>(10, actual.BillCount(UnitedStatesTender.OneDollar));
}
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));
}
}