/// <summary>
/// Purchase an item from the machine
/// </summary>
/// <param name="slotID">The slot identifier</param>
/// <returns>The vended product</returns>
public VendingMachineItem Purchase(string slotID)
{
// Translate the slot to all uppercase for comparison
slotID = slotID.ToUpper();
// check if there is anything at the slot
if (GetQuantityOfSlot(slotID) > 0)
{
// is there enough money?
if (_currentBalance > GetCostOfSlot(slotID))
{
// decrement the balance by the cost of the item
_currentBalance -= GetCostOfSlot(slotID);
// get the item from the slot
VendingMachineItem purchasedItem = GetItemOutOfSlot(slotID);
// log the purchase
FileFunctions.LogTransaction(purchasedItem.itemName + " " + slotID, purchasedItem.price, _currentBalance);
// return the item to the purchaser
return(purchasedItem);
}
// If not enough money, through InsufficientFundsException
throw new InsufficientFundsException();
}
// if there is nothing in slot, throw and OutOfStockException
throw new OutOfStockException();
}
/// <summary>
/// Method to return change from the vending machine
/// </summary>
/// <returns>A changedrawer object containing the change breakdown</returns>
public ChangeDrawer ReturnChange()
{
// Log the transaction. Do it here since the CurrentBalance will change after MakeChange is called
FileFunctions.LogTransaction("GIVE CHANGE", CurrentBalance, 0M);
ChangeDrawer changeDrawer = new ChangeDrawer();
changeDrawer.MakeChange(CurrentBalance);
return(changeDrawer);
}
/// <summary>
/// Public method to add money to the vending machine's balance
/// </summary>
/// <param name="dollars">Amount of dollars to add.</param>
/// <returns>The machine balance after the money is added</returns>
public decimal FeedMoney(int dollars)
{
try
{
_currentBalance += dollars;
}
catch (Exception e)
{
throw e;
}
// Log it
FileFunctions.LogTransaction("FEED MONEY", (decimal)dollars, CurrentBalance);
return(CurrentBalance);
}
/// <summary>
/// Public method to add money to the vending machine's balance
/// </summary>
/// <param name="dollars">Amount of dollars to add.</param>
/// <returns>The machine balance after the money is added</returns>
public decimal FeedMoney(int dollars)
{
// check for negative values. Need to check here in case this class is used elsewhere
if (dollars < 0)
{
throw new InvalidDollarAmount();
}
try
{
_currentBalance += dollars;
}
catch (Exception e)
{
throw e;
}
// Log it
FileFunctions.LogTransaction("FEED MONEY", (decimal)dollars, CurrentBalance);
return(CurrentBalance);
}
