using System;

using System.Collections.Concurrent;

using System.Reflection;

​

public class Program

{

    public abstract class SmartColor<TColor> where TColor : SmartColor<TColor> {

        private static readonly ConcurrentDictionary<string, TColor> _items = new();

​

        protected SmartColor(string code, string name) {

            Code = code;

            Name = name;

            //register all colors

            foreach (var field in typeof(TColor).GetFields(BindingFlags.Public | BindingFlags.Static)) {

                TColor? item = (TColor?)field.GetValue(null);

                if (item is not null) {

                    Register(item);

                }

            }

        }

​

        public string Code { get; }

​

        public string Name { get; }

​

        public static TColor FromCode(string code) {

            if (_items.TryGetValue(code, out var result)) {

                return result;

            }

            return null;

        }

​

        private void Register(TColor item) {

            _items.GetOrAdd(item.Code, item);

        }

    }

​

    public class WebColor : SmartColor<WebColor> {

        public static readonly WebColor White = new WebColor("#ffffff", nameof(White));

        public static readonly WebColor Black = new WebColor("#000000", nameof(Black));

​

        protected WebColor(string code, string name) : base(code, name) {

        }

    }

​

    public static void Main()

    {

        WebColor color = WebColor.FromCode("#ffffff");

        Console.WriteLine(color.Name);

    }

}