Engine Class

using System;
   using robotManager.FiniteStateMachine;

   namespace EngineSample
   {
       class Program
       {
           class Context
           {
               internal Engine Engine { get; set; }
               internal int I { get; set; }
           }

           #region States

           class EvenNumberState : State
           {
               internal EvenNumberState(Context c)
               {
                   Context = c;
               }
               Context Context { get; set; }

               public override bool NeedToRun
               {
                   get
                   {
                       return Context.I % 2 == 0; // return true if number is even
                   }
               }

               public override void Run()
               {
                   Console.WriteLine("Number is even: " + Context.I);
                   Context.I++;
               }
           }

           class OddNumberState : State
           {
               internal OddNumberState(Context c)
               {
                   Context = c;
               }
               Context Context { get; set; }

               public override bool NeedToRun
               {
                   get
                   {
                       return Context.I % 2 != 0; // return true if number is odd
                   }
               }

               public override void Run()
               {
                   Console.WriteLine("Number is odd: " + Context.I);
                   Context.I++;
               }
           }

           class FinishState : State
           {
               internal FinishState(Context c)
               {
                   Context = c;
               }
               Context Context { get; set; }

               public override bool NeedToRun
               {
                   get
                   {
                       return Context.I == 5;
                   }
               }

               public override void Run()
               {
                   Console.WriteLine("Finish: " + Context.I);
                   Context.Engine.StopEngine();
               }
           }

           class AlwaysTrueState : State
           {
               public override bool NeedToRun
               {
                   get
                   {
                       return true;
                   }
               }

               public override void Run()
               {
                   Console.WriteLine("AlwaysTrueState!");
               }
           }

           #endregion States

           static void Main(string[] args)
           {
               var c = new Context
               {
                   Engine = new Engine(),
                   I = 0
               };

               c.Engine.AddState(new FinishState(c) { Priority = 4 }); // if state.NeedToRun (c.I == 5) then state.Run and return to the state with the highest priority (this state) else check next state (OddNumberState)
               c.Engine.AddState(new OddNumberState(c) { Priority = 3 }); // if state.NeedToRun (c.I is odd) then state.Run and return to the state with the highest priority (FinishState) else check next state (EvenNumberState)
               c.Engine.AddState(new EvenNumberState(c) { Priority = 2 }); // ....
               c.Engine.AddState(new AlwaysTrueState() { Priority = 1 }); // should never be called, the number can be odd or even.

               c.Engine.StartEngine(25); // start engine in new thread

               Console.ReadKey();
           }
       }
   }