private decimal CalculateDiscountAmount(SpecialOfferRule specialOfferRule, ShoppingBasket shoppingBasket)
{
// SpecialOfferRule product not matched basket
int specialOfferRuleMatchCount = shoppingBasket.GetItemCountById(specialOfferRule.SpecialOfferMatchRule.Product.Id) / specialOfferRule.SpecialOfferMatchRule.MinimumQuantity;
if (specialOfferRuleMatchCount == 0)
{
return(0m);
}
// SpecialOfferDiscount product not found in basket
int discountedItemCount = shoppingBasket.GetItemCountById(specialOfferRule.SpecialOfferDiscountRule.Product.Id);
if (discountedItemCount == 0)
{
return(0m);
}
// if there is a maximum limit on discountCount
int discountAppliedCount = Math.Min(specialOfferRuleMatchCount, discountedItemCount);
if (specialOfferRule.SpecialOfferDiscountRule.MaximumQuantity.HasValue)
{
discountAppliedCount = Math.Min(discountedItemCount, specialOfferRule.SpecialOfferDiscountRule.MaximumQuantity.Value);
}
// calculate the discount based on the basket items
decimal percentageDiscount = Decimal.Divide(specialOfferRule.SpecialOfferDiscountRule.DiscountPercent, 100);
decimal discountAmount = Decimal.Multiply(specialOfferRule.SpecialOfferDiscountRule.Product.Price, percentageDiscount);
return(Decimal.Multiply(discountAmount, discountAppliedCount));
}
public void CheckSpecialOfferDiscountRuleNullArgumentException()
{
try
{
SpecialOfferRule specialOfferRule = new SpecialOfferRule(
new SpecialOfferMatchRule(new Product(1, "dummy", 0.2m), 1),
new SpecialOfferDiscountRule(null, 1));
Assert.Fail("This should throw null exception");
}
catch (ArgumentNullException ex)
{
Assert.IsTrue(ex.ParamName == "product");
}
}
public static SpecialOffersDL GetAppleBeansBreadSpecialOffers(ProductsDL productsDL)
{
// 10 % off apples
SpecialOfferRule apples10percentOff = new SpecialOfferRule(new SpecialOfferMatchRule(productsDL.GetProductByName("apple"), 1),
new SpecialOfferDiscountRule(productsDL.GetProductByName("apple"), 10));
// buy 2 cans of beans, get 1 loaf of bread 50% off
SpecialOfferRule twoCans1BreadLoaf = new SpecialOfferRule(new SpecialOfferMatchRule(productsDL.GetProductByName("beans"), 2),
new SpecialOfferDiscountRule(productsDL.GetProductByName("bread"), 50, 1));
SpecialOffersDL specialOffers = new SpecialOffersDL(new List <SpecialOfferRule>()
{
apples10percentOff, twoCans1BreadLoaf
});
return(specialOffers);
}
public static SpecialOffersDL GetSpecialOffers3oranges1applefree(ProductsDL products)
{
// buy 90 % off strawberries
SpecialOfferRule apples10percentOff = new SpecialOfferRule(
new SpecialOfferMatchRule(products.GetProductByName("Strawberries"), 1),
new SpecialOfferDiscountRule(products.GetProductByName("Strawberries"), 90));
// buy 3 oranges, get 1 apple for free
SpecialOfferRule threeOrangesOneAppleFree = new SpecialOfferRule(
new SpecialOfferMatchRule(products.GetProductByName("oranges"), 3),
new SpecialOfferDiscountRule(products.GetProductByName("apple"), 100, 1));
SpecialOffersDL specialOffers = new SpecialOffersDL(new List <SpecialOfferRule>()
{
apples10percentOff, threeOrangesOneAppleFree
});
return(specialOffers);
}
static void Main(string[] args)
{
try
{
// Create Product List for example in paper
ProductsDL productsDL = new ProductsDL(new List <Product>()
{
new Product(1, "Beans", 0.65m),
new Product(2, "Bread", 0.80m),
new Product(3, "Milk", 1.30m),
new Product(4, "Apple", "Apples", 1.00m)
});
// create special offers
// Offer 1: 10% off apples
SpecialOfferRule apples10percentOff = new SpecialOfferRule(
new SpecialOfferMatchRule(productsDL.GetProductByName("apple"), 1),
new SpecialOfferDiscountRule(productsDL.GetProductByName("apple"), 10));
// Offer 2: Buy 2 cans of beans get 1 loaf of bread 50 percent off
SpecialOfferRule twoCans1BreadLoaf = new SpecialOfferRule(
new SpecialOfferMatchRule(productsDL.GetProductByName("beans"), 2),
new SpecialOfferDiscountRule(productsDL.GetProductByName("bread"), 50, 1));
SpecialOffersDL specialOffersDL = new SpecialOffersDL(new List <SpecialOfferRule>()
{
apples10percentOff, twoCans1BreadLoaf
});
// process user imput with products and special offers
IAppMain appMain = new AppMain(productsDL, specialOffersDL);
string output = appMain.Process(args);
Console.WriteLine(output);
}
catch (Exception ex)
{
// log out error not just to console.
Console.WriteLine("Fatal Error occured: ", ex);
}
}
public SpecialOfferApplied(SpecialOfferRule specialOfferRule, decimal discountedAmount)
{
SpecialOfferRule = specialOfferRule;
DiscountedAmount = discountedAmount;
}
