/// <summary>
/// Calculates the total cost of an order.
/// </summary>
/// <param name="orderId">The unique identifier of the order.</param>
/// <returns>The total cost of the order.</returns>
public double CalculateOrderTotal(int orderId)
{
var coffees = _coffeeRepository.GetByOrderId(orderId);
if (!coffees.Any())
{
throw new ArgumentOutOfRangeException("There is no coffee added to the order. Please add coffee before attempting to purchase your order.");
}
var totalSmalls = coffees.Count(c => c.Size == "small");
var totalMediums = coffees.Count(c => c.Size == "medium");
var totalLarges = coffees.Count(c => c.Size == "large");
var totalCream = coffees.Sum(c => c.AmountOfCream);
var totalSugar = coffees.Sum(c => c.AmountOfSugar);
return(totalSmalls * CostOfSmallCoffee + totalMediums * CostOfMediumCoffee + totalLarges * CostOfLargeCoffee + totalCream * CostOfCream + totalSugar * CostOfSugar);
}
