Update rules pattern examples

Author: nemanjarogic

src/AdditionalPatterns/Rules/RulesLibrary/Common/Customer.cs

@@ -2,9 +2,13 @@
 
 public class Customer
 {
-    public DateTime? DateOfFirstPurchase { get; set; }
-
-    public DateTime DateOfBirth { get; set; }
-
-    public bool IsVeteran { get; set; }
-}
+    public Customer(DateTime dateOfBirth, bool isVeteran, DateTime? dateOfFirstPurchase = null)
+    {
+        DateOfBirth = dateOfBirth;
+        IsVeteran = isVeteran;
+        DateOfFirstPurchase = dateOfFirstPurchase;
+    }
+    public DateTime DateOfBirth { get; }
+    public DateTime? DateOfFirstPurchase { get; }
+    public bool IsVeteran { get; }
+}

src/AdditionalPatterns/Rules/RulesLibrary/Executor.cs

@@ -13,4 +13,4 @@ public override void Execute()
         MotivatingExecutor.Execute();
         RulesExecutor.Execute();
     }
-}
+}

src/AdditionalPatterns/Rules/RulesLibrary/MotivatingExample/DiscountCalculator.cs

@@ -11,28 +11,28 @@ public class DiscountCalculator
 {
     public decimal Calculate(Customer customer)
     {
-        decimal discount = 0;
+        var discount = 0m;
         var currentDate = DateTime.Now;
 
         if (customer.DateOfBirth < currentDate.AddYears(-65))
         {
-            // Senior discount of 5%
+            // Senior discount of 5%.
             discount = 0.05m;
         }
 
         if (customer.DateOfFirstPurchase.HasValue)
         {
             if (customer.DateOfFirstPurchase.Value < currentDate.AddYears(-1))
             {
-                // After 1 year, loyal customers get 10% discount
+                // After 1 year, loyal customers get 10% discount.
                 discount = Math.Max(discount, 0.10m);
                 if (customer.DateOfFirstPurchase.Value < currentDate.AddYears(-5))
                 {
-                    // After 5 years, loyal customers get 12% discount
+                    // After 5 years, loyal customers get 12% discount.
                     discount = Math.Max(discount, 0.12m);
                     if (customer.DateOfFirstPurchase.Value < currentDate.AddYears(-10))
                     {
-                        // After 10 years, loyal customers get 20% discount
+                        // After 10 years, loyal customers get 20% discount.
                         discount = Math.Max(discount, 0.20m);
                     }
                 }
@@ -41,20 +41,20 @@ public decimal Calculate(Customer customer)
                     customer.DateOfBirth.Day == DateTime.Today.Day)
                 {
                     // Loyal customers can get an additional 10% discount
-                    // if they purchase a product on their birthday
+                    // if they purchase a product on their birthday.
                     discount += 0.10m;
                 }
             }
         }
         else
         {
-            // First time purchase discount of 15%
+            // First time purchase discount of 15%.
             discount = Math.Max(discount, 0.15m);
         }
 
         if (customer.IsVeteran)
         {
-            // Veterans get 10% discount
+            // Veterans get 10% discount.
             discount = Math.Max(discount, 0.10m);
         }
 

src/AdditionalPatterns/Rules/RulesLibrary/MotivatingExample/MotivatingExecutor.cs

@@ -9,17 +9,14 @@ public static void Execute()
     {
         ConsoleExtension.WriteSeparator("Motivating example");
 
-        var customer = new Customer()
-        {
-            DateOfBirth = DateTime.Now.AddYears(-70),
-            DateOfFirstPurchase = DateTime.Today.AddYears(-6),
-            IsVeteran = false,
-        };
+        var customer = new Customer(
+            dateOfBirth: DateTime.Now.AddYears(-70),
+            dateOfFirstPurchase: DateTime.Today.AddYears(-6),
+            isVeteran: false);
 
         var discountCalculator = new DiscountCalculator();
-
         var discountPercentage = discountCalculator.Calculate(customer);
 
-        Console.WriteLine($"Customer can get a {discountPercentage:P2} discount on any product.");
+        Console.WriteLine($"The customer can get a {discountPercentage:P2} discount on any product.");
     }
-}
+}

src/AdditionalPatterns/Rules/RulesLibrary/RulesExample/DiscountCalculator.cs

@@ -39,4 +39,4 @@ public decimal Calculate(Customer customer)
 
         return discount;
     }
-}
+}

src/AdditionalPatterns/Rules/RulesLibrary/RulesExample/Rules/BirthdayDiscountRule.cs

@@ -15,4 +15,4 @@ public decimal CalculateDiscount(Customer customer)
 
         return 0;
     }
-}
+}

src/AdditionalPatterns/Rules/RulesLibrary/RulesExample/Rules/Common/IDiscountRule.cs

@@ -5,4 +5,4 @@ namespace RulesLibrary.RulesExample.Rules.Common;
 public interface IDiscountRule
 {
     decimal CalculateDiscount(Customer customer);
-}
+}

src/AdditionalPatterns/Rules/RulesLibrary/RulesExample/Rules/FirstPurchaseRule.cs

@@ -14,4 +14,4 @@ public decimal CalculateDiscount(Customer customer)
 
         return 0;
     }
-}
+}

src/AdditionalPatterns/Rules/RulesLibrary/RulesExample/Rules/LoyalCustomerRule.cs

@@ -27,4 +27,4 @@ public decimal CalculateDiscount(Customer customer)
 
         return 0;
     }
-}
+}

src/AdditionalPatterns/Rules/RulesLibrary/RulesExample/Rules/SeniorRule.cs

@@ -14,4 +14,4 @@ public decimal CalculateDiscount(Customer customer)
 
         return 0;
     }
-}
+}