using System;
using System.Collections.Generic;
using System.Linq;

namespace NestedSetModelTest
{
    internal class Program
    {
        private static List<Node> list = new List<Node>();

        private static void Main(string[] args)
        {
            var root = CreateTree();
            Add(root);
            var i = 1;
            foreach (var item in list)
            {
                item.Left = i++;
            }
            list.Reverse();
            foreach (var item in list)
            {
                item.Right = i++;
            }
            list.Reverse();
            foreach (var item in list)
            {
                Console.WriteLine($"{item.Name}:{item.Number},{item.Left}-{item.Right}");
            }
        }

        private static void Add(Node node)
        {
            list.Add(node);
            if (node.Children.Any())
            {
                foreach (var item in node.Children.OrderBy(o => o.DisplayOrder))
                {
                    Add(item);
                }
            }
        }

        private static Node CreateTree()
        {
            var root = new Node
            {
                Name = "root",
                Number = "1-18",
                Children = new List<Node> {
                    new Node{
                        Name="Fruit",
                        Number="2-11",
                        Children=new List<Node>{
                            new Node{
                                Name="Red",
                                Number="3-6",
                                Children=new List<Node>
                                {
                                    new Node{
                                        Name="Cherry",
                                        Number="4-5"
                                    }
                                }
                            },
                            new Node{
                                Name="Yellow",
                                Number="7-10",
                                DisplayOrder=1,
                                Children=new List<Node>
                                {
                                    new Node{
                                        Name="Banana",
                                        Number="8-9"
                                    }
                                }
                            }
                        }
                    },
                    new Node{
                        Name="Meat",
                        Number="12-17",
                        DisplayOrder=1,
                        Children=new List<Node>{
                            new Node{
                                Name="Beef",
                                Number="13-14"
                            },
                            new Node{
                                Name="Port",
                                Number="15-16",
                                DisplayOrder=1,
                            }
                        }
                    }
                }
            };
            return root;
        }
    }
}