using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SampleConsoleAppDelegate
{
    //This is a delegate type
    //public delegate void LogDelegate(string message);
    internal class Program
    {

        public class Model
        {
            public int A { get; set; }
            public string B { get; set; }
        }


        public delegate void LogDelegate(string message);

        static void Main(string[] args)
        {
            //This is a variable of type of delegate           
            LogDelegate myLogger;
            Action<int, string> myLogger2;
            Func<int, string, bool> myLogger3;

            //This is assigning the delegate variable by an instance of the delegate
            myLogger = Log;
            myLogger2 = Log2;
            myLogger3 = Log3;

            //Or the following syntax:
            //myLogger = new LogDelegate(Log);

            //Or the following syntax:
            //myLogger = (message) => Console.WriteLine(message);

            //Or the following syntax:
            //myLogger = delegate (string message) { Console.WriteLine(message); };

            //This is calling the delegate
            if (myLogger != null)
                myLogger("This is a message!");

            // Or the following Syntax:
            myLogger?.Invoke("This is a message 2!");
            myLogger2?.Invoke(4, "Test with action");

            bool ret = myLogger3.Invoke(4, "Test with func");



            var list = new[] {
                new Model {A= 1, B= "One"},
                new Model { A= 2, B= "Two"},
                new Model { A= 3, B= "Three"},
            }.ToList();
            var item = list.Find(x => x.A == 52);
            //var item = list.Find(new Predicate<Model>(x => x.A == 2));
            //var item = list.Find(MyPredicate);
            var item2 = list.Find(x => MyPredicate(x));


            Console.WriteLine("Press enter to exit.");
            Console.ReadLine();
        }
        private static void Log(string message)
        {
            Console.WriteLine(message);
        }
        private static void Log2(int id, string message)
        {
            Console.WriteLine($"{id}, {message}");
        }
        private static bool Log3(int id, string message)
        {
            Console.WriteLine($"{id}, {message}");
            return true;
        }
        static bool MyPredicate(Model input)
        {
            return input.A == 2;
        }
    }
}