Add Design Patterns

.gitignore

@@ -4,3 +4,4 @@ obj/
 riderModule.iml
 /_ReSharper.Caches/
 .idea/
+*.user

DecoratorLib/Component.cs

@@ -0,0 +1,9 @@
+namespace DecoratorLib;
+
+public class Component : IComponent
+{
+    public void Log()
+    {
+        Console.WriteLine("Component Log");
+    }
+}

DecoratorLib/DecoratorLib.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net10.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+</Project>

DecoratorLib/IComponent.cs

@@ -0,0 +1,6 @@
+namespace DecoratorLib;
+
+public interface IComponent
+{
+    void Log();
+}

DesignPatterns.sln

@@ -2,6 +2,12 @@
 Microsoft Visual Studio Solution File, Format Version 12.00
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DesignPatterns", "DesignPatterns\DesignPatterns.csproj", "{97DCCECE-E259-4D62-B8D4-B713C4029578}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "VisitorLib", "VisitorLib\VisitorLib.csproj", "{148F50F8-70D5-462A-9C1E-F25463EF7BB4}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DecoratorLib", "DecoratorLib\DecoratorLib.csproj", "{298AAC41-87D0-475E-B97C-4F9389549F3E}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ProxyLib", "ProxyLib\ProxyLib.csproj", "{76B2946E-1252-442D-B995-F46D4B1A3520}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -12,5 +18,17 @@ Global
 		{97DCCECE-E259-4D62-B8D4-B713C4029578}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{97DCCECE-E259-4D62-B8D4-B713C4029578}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{97DCCECE-E259-4D62-B8D4-B713C4029578}.Release|Any CPU.Build.0 = Release|Any CPU
+		{148F50F8-70D5-462A-9C1E-F25463EF7BB4}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{148F50F8-70D5-462A-9C1E-F25463EF7BB4}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{148F50F8-70D5-462A-9C1E-F25463EF7BB4}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{148F50F8-70D5-462A-9C1E-F25463EF7BB4}.Release|Any CPU.Build.0 = Release|Any CPU
+		{298AAC41-87D0-475E-B97C-4F9389549F3E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{298AAC41-87D0-475E-B97C-4F9389549F3E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{298AAC41-87D0-475E-B97C-4F9389549F3E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{298AAC41-87D0-475E-B97C-4F9389549F3E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{76B2946E-1252-442D-B995-F46D4B1A3520}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{76B2946E-1252-442D-B995-F46D4B1A3520}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{76B2946E-1252-442D-B995-F46D4B1A3520}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{76B2946E-1252-442D-B995-F46D4B1A3520}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 EndGlobal

DesignPatterns/Builder/Warehouse.cs

@@ -0,0 +1,27 @@
+namespace DesignPatterns;
+
+public class Warehouse(Warehouse.WarehouseBuilder warehouseBuilder)
+{
+    public int Capacity { get; } = warehouseBuilder.Capacity;
+    public List<string> Stock { get; } = warehouseBuilder.Stock ?? [];
+    
+    public override string ToString() {
+        return $"Capacity: {Capacity},  Stock: {string.Join(",", Stock)}";
+    }
+    public class WarehouseBuilder(int capacity)
+    {
+        public int Capacity { get; } = capacity;
+        public List<string>? Stock { get; private set; }
+        public WarehouseBuilder SetStock(List<string> stock)
+        {
+            Stock = stock;
+            return this;
+        }
+        public Warehouse Build()
+        {
+            var warehouse = new Warehouse(this);
+            return warehouse;
+        }
+    }
+
+}

DesignPatterns/Decorator/ComponentDecorator.cs

@@ -0,0 +1,9 @@
+using DecoratorLib;
+
+namespace DesignPatterns.Decorator;
+
+public abstract class ComponentDecorator(IComponent component) : IComponent
+{
+    private readonly IComponent _component = component;
+    public abstract void Log();
+}

DesignPatterns/Decorator/FailableComponentComponentDecorator.cs

@@ -0,0 +1,22 @@
+using DecoratorLib;
+
+namespace DesignPatterns.Decorator;
+
+public class FailableComponentComponentDecorator(IComponent comp) : ComponentDecorator(comp)
+{
+    private readonly IComponent _comp = comp;
+    public bool ShouldFail { get; set; }
+
+    public override void Log()
+    {
+        if (ShouldFail)
+        {
+            throw new Exception("FailableComponentComponentDecorator should fail");
+        }
+        _comp.Log();
+    }
+    public string GetLogString()
+    {
+        return "Component Log";
+    }
+}

DesignPatterns/DesignPatterns.csproj

@@ -7,4 +7,10 @@
         <Nullable>enable</Nullable>
     </PropertyGroup>
 
+    <ItemGroup>
+      <ProjectReference Include="..\DecoratorLib\DecoratorLib.csproj" />
+      <ProjectReference Include="..\ProxyLib\ProxyLib.csproj" />
+      <ProjectReference Include="..\VisitorLib\VisitorLib.csproj" />
+    </ItemGroup>
+
 </Project>

DesignPatterns/Factory/Book.cs

@@ -0,0 +1,11 @@
+namespace DesignPatterns;
+
+sealed class Book : Product
+{
+    internal Book()
+    {
+        
+    }
+    public new double Price { get; set; } = 20;
+    public override string ToString() => "Book";
+}

DesignPatterns/Factory/Product.cs

@@ -0,0 +1,16 @@
+namespace DesignPatterns;
+
+public abstract class Product
+{
+    public double Price { get; set; } = 5;
+    public override string ToString() => "Product";
+    public static Product FactoryMethod(string productName)
+    {
+        return productName switch
+        {
+            "Smartphone" => new Smartphone(),
+            "Book" => new Book(),
+            _ => throw new ArgumentException()
+        };
+    }
+}

DesignPatterns/Factory/Smartphone.cs

@@ -0,0 +1,11 @@
+namespace DesignPatterns;
+
+sealed class Smartphone : Product
+{
+    internal Smartphone()
+    {
+        
+    }
+    public new double Price { get; set; } = 300;
+    public override string ToString() => "Smartphone";
+}

DesignPatterns/Program.cs

@@ -1,3 +1,39 @@
-// See https://aka.ms/new-console-template for more information
+using DecoratorLib;
+using DesignPatterns;
+using DesignPatterns.Decorator;
+using ProxyLib;
+using VisitorLib;
 
-Console.WriteLine("Hello, World!");
+LoggerSingleton.Instance.Logger.WriteLine("Hello World!");
+var product = Product.FactoryMethod("Smartphone");
+Console.WriteLine(product);
+product = Product.FactoryMethod("Book");
+Console.WriteLine(product);
+var warehouseBuilder = new Warehouse.WarehouseBuilder(12);
+warehouseBuilder.SetStock(["abc", "def"]);
+var warehouse = warehouseBuilder.Build();
+Console.WriteLine($"{warehouse.Capacity}, {warehouse.Stock}");
+var visitor = new LoggingVisitor();
+List<Shape> shapes =
+[
+    new Rectangle
+    {
+        Area = 12,
+    },
+    new Circle()
+    {
+        Radius = 5,
+    }
+];
+shapes.ForEach(shape => shape.Accept(visitor));
+var decorator = new FailableComponentComponentDecorator(new Component())
+{
+    ShouldFail = false,
+};
+Console.WriteLine(decorator.GetLogString());
+decorator.Log();
+ISubject subject = new SubjectProxy
+{
+    CanLog = true,
+};
+subject.Log();

DesignPatterns/Singleton/LoggerSingleton.cs

@@ -0,0 +1,17 @@
+namespace DesignPatterns;
+
+public class LoggerSingleton
+{
+    private static LoggerSingleton? _instance;
+
+    public static LoggerSingleton Instance
+    {
+        get
+        {
+            _instance ??= new LoggerSingleton();
+            return _instance;
+        }
+    }
+
+    public TextWriter Logger => Console.Out;
+}

DesignPatterns/Visitor/LoggingVisitor.cs

@@ -0,0 +1,16 @@
+using VisitorLib;
+
+namespace DesignPatterns;
+
+public class LoggingVisitor: IShapeVisitor
+{
+
+    public void VisitRectangle(Rectangle rectangle)
+    {
+        Console.WriteLine($"Rect, Area: {rectangle.Area}");
+    }
+    public void VisitCircle(Circle circle)
+    {
+        Console.WriteLine($"Circle, Radius: {circle.Radius}");
+    }
+}

ProxyLib/ConcreteSubject.cs

@@ -0,0 +1,10 @@
+namespace ProxyLib;
+
+internal class ConcreteSubject: ISubject
+{
+
+    public void Log()
+    {
+        Console.WriteLine("ConcreteSubject Log");
+    }
+}

ProxyLib/ISubject.cs

@@ -0,0 +1,6 @@
+namespace ProxyLib;
+
+public interface ISubject
+{
+    void Log();
+}

ProxyLib/ProxyLib.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net10.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+</Project>

ProxyLib/SubjectProxy.cs

@@ -0,0 +1,13 @@
+namespace ProxyLib;
+
+public class SubjectProxy : ISubject
+{
+    public bool CanLog { get; set; }
+    private readonly ISubject _subject = new ConcreteSubject();
+
+    public void Log()
+    {
+        if (!CanLog) return;
+        _subject.Log();
+    }
+}

VisitorLib/Circle.cs

@@ -0,0 +1,10 @@
+namespace VisitorLib;
+
+public class Circle: Shape
+{
+    public int Radius { get; set; }
+    public override void Accept(IShapeVisitor visitor)
+    {
+        visitor.VisitCircle(this);
+    }
+}

VisitorLib/IShapeVisitor.cs

@@ -0,0 +1,7 @@
+namespace VisitorLib;
+
+public interface IShapeVisitor
+{
+    void VisitRectangle(Rectangle rectangle);
+    void VisitCircle(Circle rectangle);
+}

VisitorLib/Rectangle.cs

@@ -0,0 +1,10 @@
+namespace VisitorLib;
+
+public class Rectangle: Shape
+{
+    public int Area { get; set; }
+    public override void Accept(IShapeVisitor visitor)
+    {
+        visitor.VisitRectangle(this);
+    }
+}

VisitorLib/Shape.cs

@@ -0,0 +1,6 @@
+namespace VisitorLib;
+
+public abstract class Shape
+{
+    public abstract void Accept(IShapeVisitor visitor);
+}

VisitorLib/VisitorLib.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net10.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+        <RootNamespace>VisitorLib</RootNamespace>
+    </PropertyGroup>
+
+</Project>