using System;

public class Program

{

    public void Main()

    {

        IHandler first = HandlerFactory.CreateInstance(

            HandlerType.Handler1,

            ParamBuilder.start().withOne("x").withTwo("y").build());

        IHandler second = HandlerFactory.CreateInstance(

            HandlerType.Handler2,

            ParamBuilder.start().withAlpha(1).withBeta(new DateTime()).build());

        IHandler third = HandlerFactory.CreateInstance(

            HandlerType.Handler3,

            ParamBuilder.start().withMickey(":)").withMouse(1L).build());

        first.DoStuff();

        second.DoStuff();

        third.DoStuff();

    }

    class HandlerFactory

    {

        public static IHandler CreateInstance(HandlerType type, IParam param)

        {

            switch (type) {

            case HandlerType.Handler1: return new Handler1(param);

            case HandlerType.Handler2: return new Handler2(param);

            case HandlerType.Handler3: return new Handler3(param);

            default: throw new NotSupportedException();

            }

        }

    }

    enum HandlerType { Handler1, Handler2, Handler3 

    }

    interface IHandler { void DoStuff(); }

    class Handler1 : IHandler {

        private Param1 numbers; private Param2 letters; private Param3 disney;

        public Handler1(IParam param) {

            if (param is Param1) numbers = (Param1) param;

            if (param is Param2) letters = (Param2) param;

            if (param is Param3) disney = (Param3) param;

        }

        public void DoStuff() { Console.WriteLine("I am alive - Handler 1");}

    }

    class Handler2 : IHandler {

        private Param1 numbers; private Param2 letters; private Param3 disney;

        public Handler2(IParam param) {

            if (param is Param1) numbers = (Param1) param;

            if (param is Param2) letters = (Param2) param;

            if (param is Param3) disney = (Param3) param;

        }

        public void DoStuff() { Console.WriteLine("I am alive - Handler 2");}

    }

    class Handler3 : IHandler {

        private Param1 numbers;

        private Param2 letters;

        private Param3 disney;

        public Handler3(IParam param) {

            if (param is Param1) numbers = (Param1) param;

            if (param is Param2) letters = (Param2) param;

            if (param is Param3) disney = (Param3) param;

        }

        public void DoStuff() { Console.WriteLine("I am alive - Handler 3");}

    }

    interface IParam {

        string One { get; } string Two { get; } // first param class

        int Alpha { get; } DateTime Beta { get; } // second param class

        string Mickey { get; } long Mouse { get; } // third param class

    }

    class ParamBuilder {

        private string one, two;

        private int? alpha; private DateTime? beta;

        private  string mickey; private long? mouse;

        public static ParamBuilder start() { return new ParamBuilder(); }

        public IParam build() {

            if (!string.IsNullOrEmpty(one) && !string.IsNullOrEmpty(one)) {

                return new Param1(one, two);

            }

            if (alpha.HasValue && beta.HasValue) {

                return new Param2(alpha.Value, beta.Value);

            }

            if (!string.IsNullOrEmpty(mickey) && mouse.HasValue) {

                return new Param3(mickey, mouse.Value);

            }

            throw new NotSupportedException();

        }

        public ParamBuilder withOne(string one) { this.one = one; return this; }

        public ParamBuilder withTwo(string two) { this.two = two; return this; }

        public ParamBuilder withAlpha(int alpha) { this.alpha = alpha; return this; }

        public ParamBuilder withBeta(DateTime beta) { this.beta = beta; return this; }

        public ParamBuilder withMickey(string m) { this.mickey = m; return this; }

        public ParamBuilder withMouse(long m) { this.mouse = m; return this; }

    }

    class Param1 : IParam {

        public string One { private set; get; }

        public string Two { private set; get; }

        public int Alpha { get {throw new NotImplementedException();} }

        public DateTime Beta { get {throw new NotImplementedException();} }

        public string Mickey { get {throw new NotImplementedException();} }

        public long Mouse { get {throw new NotImplementedException();} }

        public Param1(string one, string two) {

            One = one; Two = two;

        }

    }

    class Param2 : IParam {

        public int Alpha { private set; get; }

        public DateTime Beta { private set; get; }

        public string One { get {throw new NotImplementedException();} }

        public string Two { get {throw new NotImplementedException();} }

        public string Mickey { get {throw new NotImplementedException();} }

        public long Mouse { get {throw new NotImplementedException();} }

        public Param2(int alpha, DateTime beta) {

            Alpha = alpha; Beta = beta;

        }

    }

    class Param3 : IParam {

        public string Mickey { private set; get; }

        public long Mouse { private set; get; }

        public string One { get {throw new NotImplementedException();} }

        public string Two { get {throw new NotImplementedException();} }

        public int Alpha { get {throw new NotImplementedException();} }

        public DateTime Beta { get {throw new NotImplementedException();} }

        public Param3(string mi, long mo) {

            Mickey = mi; Mouse = mo;

        }

    }

}