using Microsoft.Extensions.DependencyInjection;

using System.Threading.Tasks;

using System;

using Decor;

​

public class LoggingDecorator : IDecorator

{

    public async Task OnInvoke(Call call)

    {

        Console.WriteLine("Will do some work!");

        await call.Next();

        Console.WriteLine("Work is finished!");

    }

}

​

public class CachingDecorator : IDecorator

{

    public async Task OnInvoke(Call call)

    {       

        await call.Next();      

        Console.WriteLine("Stuffed {0} in the cache!", call.ReturnValue);

    }

}

​

public interface IWorker

{

    string DoWork();

    string SomeOtherWork(string s);

}

​

public class Worker : IWorker

{

    [Decorate(typeof(LoggingDecorator))]

    [Decorate(typeof(CachingDecorator))]

    public string DoWork()

    {

        Console.WriteLine("Working...");

        return DateTime.Now.ToString();

    }

    [Decorate(typeof(LoggingDecorator))]

    [Decorate(typeof(CachingDecorator))]

    public string SomeOtherWork(string s)

    {

        Console.WriteLine("Some Other Working...");

        return "Hello " + s;

    }

}

​

public class Program

{

    static void Main()

    {

        var serviceProvider = new ServiceCollection()

            .AddTransient<LoggingDecorator>()

            .AddTransient<CachingDecorator>()

            .AddSingleton<IWorker, Worker>()

            .Decorate<IWorker>()

            .BuildServiceProvider();

        var worker = serviceProvider.GetRequiredService<IWorker>();

        worker.DoWork();

        worker.SomeOtherWork("Fred");

        worker.SomeOtherWork("Billy");

        worker.SomeOtherWork("Bob");

    }

}