Add basic memento pattern

src/MememntoPattern/Class1.cs

@@ -1,16 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading.Tasks;
-
-namespace MememntoPattern
-{
-    // This project can output the Class library as a NuGet Package.
-    // To enable this option, right-click on the project and select the Properties menu item. In the Build tab select "Produce outputs on build".
-    public class Class1
-    {
-        public Class1()
-        {
-        }
-    }
-}

src/MememntoPattern/Employee/Caretaker.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace MememntoPattern.Employee
+{
+    /// <summary>
+    /// Caretaker
+    /// </summary>
+    public class Caretaker
+    {
+        private Stack<EmployeeMemento> employeeHistory;
+
+        public Caretaker()
+        {
+            employeeHistory = new Stack<EmployeeMemento>();
+        }
+
+        public void Save(Employee emp)
+        {
+            employeeHistory.Push(emp.Save());
+        }
+
+        public void Revert(Employee emp)
+        {
+            emp.Revert(employeeHistory.Pop());
+        }
+    }
+}

src/MememntoPattern/Employee/Employee.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace MememntoPattern.Employee
+{
+    /// <summary>
+    /// Originator
+    /// </summary>
+    public class Employee
+    {
+        public string Name { get; set; }
+
+        public string Address { get; set; }
+
+        public List<String> Phones { get; set; }
+
+        public EmployeeMemento Save()
+        {
+            return new EmployeeMemento(Name, Address);
+        }
+
+        public void Revert(EmployeeMemento memento)
+        {            
+            Name = memento.Name;
+            Address = memento.Address;
+        }
+    }
+}

src/MememntoPattern/Employee/EmployeeExample.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace MememntoPattern.Employee
+{
+    public class EmployeeExample
+    {
+        public void Run()
+        {
+            Caretaker caretaker = new Caretaker();
+            Employee e = new Employee();
+            e.Name = "Ghiuri";
+            e.Address = "Stairway to heaven";
+
+            Console.WriteLine("First saved address: {0}", e.Address);
+            caretaker.Save(e);
+
+            e.Address = "Highway to hell";
+
+            Console.WriteLine("Last saved address: {0}", e.Address);
+
+            caretaker.Save(e);
+
+            e.Address = "Home of the brave"; // No save, no home, no address
+
+            Console.WriteLine("Address before revert: {0}", e.Address);
+
+            caretaker.Revert(e);
+
+            Console.WriteLine("First reverted Address: {0}", e.Address);
+
+            caretaker.Revert(e);
+
+            Console.WriteLine("Second reverted Address: {0}", e.Address);
+
+        }
+       
+    }
+}

src/MememntoPattern/Employee/EmployeeMemento.cs

@@ -0,0 +1,22 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace MememntoPattern.Employee
+{
+    /// <summary>
+    /// Memento object
+    /// </summary>
+    public class EmployeeMemento
+    {
+        public string Name { get; private set; }
+        public string Address { get; private set; }
+
+        public EmployeeMemento(string name, string address)
+        {
+            Name = name;
+            Address = address;
+        }
+    }
+}

src/MememntoPattern/MementoPatternExamples.cs

@@ -0,0 +1,60 @@
+using MememntoPattern.Employee;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace MememntoPattern
+{
+    // This project can output the Class library as a NuGet Package.
+    // To enable this option, right-click on the project and select the Properties menu item. In the Build tab select "Produce outputs on build".
+    public class MementoPatternExamples
+    {
+        public MementoPatternExamples()
+        {
+                       
+        }
+
+        public void Run()
+        {
+            Console.WriteLine(GetWhenToUse());
+            Console.WriteLine(GetActors());
+            Console.WriteLine(GetAlternatives());
+
+            GoToNextStep();
+
+            EmployeeExample empExample = new EmployeeExample();
+            empExample.Run();
+        }
+
+        string GetWhenToUse()
+        {
+            return @"When to use:
+When you need to be able to track the state of an object,or/and restore previous states as needed
+When you cannot use simple operation undo/redo, by saving the commands (when there are side effects to the operations) - example translation";
+        }
+
+        
+
+        string GetAlternatives()
+        {
+            return @"Alternatives:
+Command undo - when operations maybe undone
+Iterative Memento - Save the changes, instead of storing the entire state again like GIT";
+        }
+
+        string GetActors()
+        {
+            return @"Actors:
+Originator: object that we want to save. It will create the actual memento.
+Caretaker: keeps the mementos
+Memento: (Magic cookie) internal state of the object";
+        }
+
+        private static void GoToNextStep()
+        {
+            Console.ReadKey();
+            Console.Clear();
+        }
+    }
+}

src/MememntoPattern/project.json

@@ -1,8 +1,9 @@
-{
+{
   "version": "1.0.0-*",
 
   "dependencies": {
-    "NETStandard.Library": "1.5.0-rc2-24027"
+    "NETStandard.Library": "1.5.0-rc2-24027",
+    "Newtonsoft.Json": "8.0.3"
   },
 
   "frameworks": {