using System;

​

public interface INotification

{

    void Send(string message);

}

​

public interface INotificationFactory

{

    INotification CreateEmailNotification();

    INotification CreateSmsNotification();

}

​

// Concrete Factory for Windows

public class WindowsNotificationFactory : INotificationFactory

{

    public INotification CreateEmailNotification() => new WindowsEmailNotification();

    public INotification CreateSmsNotification() => new WindowsSmsNotification();

}

​

public class WindowsEmailNotification : INotification

{

    public void Send(string message) => Console.WriteLine($"Windows Email sent: {message}");

}

​

public class WindowsSmsNotification : INotification

{

    public void Send(string message) => Console.WriteLine($"Windows SMS sent: {message}");

}

​

// Concrete Factory for Web

public class WebNotificationFactory : INotificationFactory

{

    public INotification CreateEmailNotification() => new WebEmailNotification();

    public INotification CreateSmsNotification() => new WebSmsNotification();

}

​

public class WebEmailNotification : INotification

{

    public void Send(string message) => Console.WriteLine($"Web Email sent: {message}");

}

​

public class WebSmsNotification : INotification

{

    public void Send(string message) => Console.WriteLine($"Web SMS sent: {message}");

}

​

// Client

class Program

{

    static void Main()

    {

        INotificationFactory factory = new WindowsNotificationFactory();

        var emailNotification = factory.CreateEmailNotification();

        emailNotification.Send("Hello via Windows Email!");

        var smsNotification = factory.CreateSmsNotification();

        smsNotification.Send("Hello via Windows SMS!");

        factory = new WebNotificationFactory();

        var webEmailNotification = factory.CreateEmailNotification();

        webEmailNotification.Send("Hello via Web Email!");

        var webSmsNotification = factory.CreateSmsNotification();

        webSmsNotification.Send("Hello via Web SMS!");

    }

}