private void VerifyCurrentOrderExists(Customer currentCustomer)
{
if (currentCustomer.getOrder() == null)
{
throw new InvalidOperationException("Order not started");
}
}
public void StartNewOrder(Customer customer)
{
if (customer.getOrder() != null)
{
throw new InvalidOperationException("Cannot start a new order while another is still in progress");
}
customer.Order = new Order(currentStock);
}