NavigationNode.cs

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

namespace TelegramBot.Navigation
{
    public abstract class NavigationNode<T> where T : NavigationNode<T>
    {
        public string HexID { get; private set; }
        public string FullAddress { get; private set; }
        public int Depth { get; private set; }
        public T Parent { get; private set; }
        protected List<T> _children = new List<T>();
        public IReadOnlyList<T> Children => _children.AsReadOnly();


        protected NavigationNode(T parent = null)
        {
            SetParent(parent);
        }
        private void _SetProperties()
        {
            _SetHexID();
            _SetDepth();
            _SetFullAddress();
        }
        private void _SetHexID()
        {
            if (Parent == null)
            {
                HexID = "r";
            }
            else
            {
                HexID = Convert.ToString(Parent._children.IndexOf(this as T), 16);
            }
        }
        private void _SetDepth()
        {
            if (Parent == null)
            {
                Depth = 0;
            }
            else
            {
                Depth = Parent.Depth + 1;
            }
        }
        private void _SetFullAddress()
        {
            FullAddress = HexID;
            T currentNode = this as T;
            for (int i = 0; i < Depth; i++)
            {
                FullAddress = FullAddress.Insert(0, currentNode.Parent.HexID);
                currentNode = currentNode.Parent;
            }
        }
        public t GetChild<t>() where t : NavigationNode<T>
        {
            return _children.Find(x => x is t) as t;
        }
        public async Task<t> GetChildAsync<t>() where t : NavigationNode<T>
        {
            return await Task.Run(() => _children.Find(x => x is t) as t);
        }
        public void SetParent(T newParent)
        {
            if (Parent != null)
            {
                Parent._children.Remove(this as T);
            }
            if (newParent != null)
            {
                if (newParent._children.Count >= 16)
                {
                    throw new ArgumentOutOfRangeException("Maximum capacity of the node has been reached", "newParent");
                }
                newParent._children.Add(this as T);
                Parent = newParent;
            }
            _SetProperties();
        }
        public T GetChild(int index)
        {
            return _children[index];
        }
    }
}