public void Apply()
{
if (_promoDatabase.HasPromotion(Id))
{
//TODO: handle already exists error better;
throw new System.Exception("Promotion already exists");
}
var applicability = ApplyApplicability();
var discount = ApplyDiscount();
_promoDatabase.AddPromotion(new Promotion(Id, Description, applicability, discount));
}
public void HappyPath_MultiBuyPromotionIsApplied()
{
//arrange
string id = "promo1";
string description = "Buy 5 get 20% off";
int qualifyingSize = 5;
decimal percent = 20;
var db = new InMemoryPromotionPersistence();
var strategy = new MultiBuyPercentStrategy(id, description, qualifyingSize, percent, db);
//act
strategy.Apply();
//assert
Assert.IsTrue(db.HasPromotion(id));
var promo = db.GetPromotion(id);
Assert.AreEqual(id, promo.Id);
Assert.AreEqual(description, promo.Description);
Assert.IsInstanceOf <PercentDiscount>(promo.Discount);
Assert.IsInstanceOf <MultiApplicability>(promo.Applicability);
Assert.AreEqual(percent, ((PercentDiscount)(promo.Discount)).GetPercent());
Assert.AreEqual(qualifyingSize, promo.Applicability.GetApplicableSize());
}
public void HappyPath_MultiBuyPromotionIsApplied()
{
//arrange
string id = "promo2";
string description = "Buy 2 get one free";
int qualifyingSize = 2;
decimal valueOfSingleItem = 20;
var db = new InMemoryPromotionPersistence();
var strategy = new MultiBuyValueStrategy(id, description, qualifyingSize, valueOfSingleItem, db);
//act
strategy.Apply();
//assert
Assert.IsTrue(db.HasPromotion(id));
var promo = db.GetPromotion(id);
Assert.AreEqual(id, promo.Id);
Assert.AreEqual(description, promo.Description);
Assert.IsInstanceOf <ValueDiscount>(promo.Discount);
Assert.IsInstanceOf <MultiApplicability>(promo.Applicability);
Assert.AreEqual(valueOfSingleItem, ((ValueDiscount)(promo.Discount)).GetValue());
Assert.AreEqual(qualifyingSize, promo.Applicability.GetApplicableSize());
}