using System;

using System.Collections.Generic;

public class Program

{

    public static string TabCountPrint(int count)

    {

        string ret_str = "";

        for(int i=0; i < count; i++)

        {

            ret_str += "\t";

        }

        return ret_str;

    }

    // --------

    public enum InventoryOwnerType

    {

        None,

        Player,

        InventoryItem

    }

​

    public struct InventoryOwner

    {

        public int id;

        public InventoryOwnerType type;

        public InventoryOwner() : this(0, InventoryOwnerType.None) { }

        public InventoryOwner(int id, InventoryOwnerType type)

        {

            this.id = id;

            this.type = type;

        }

    }

    public class Item

    {

        public int _id;

        public int _type;

        public int _amount;

        public DateTime _create_time;

        private Inventory _items;

        public Inventory items 

        {

            get

            {

                return _items;

            }   

            set 

            {

                if(_items == null)

                    _items = new Inventory();

                _items = value;

            }

        }

        public Item(int id, int type, int amount)

        {

            _id = id;

            _type = type;

            _amount = amount;

            _create_time = DateTime.Now;

        }

    }

    public class Inventory

    {

        public InventoryOwner ownerInfo = new InventoryOwner();

        public List<Item> items = new List<Item>();

​

        public Inventory() { }

        public Inventory(int ownerId)

        {

            ownerInfo.id = ownerId;

        }

        public Inventory(int ownerId, InventoryOwnerType ownerType)

        {

            ownerInfo.id = ownerId;

            ownerInfo.type = ownerType;

        }

        public Inventory(List<Item> items) 

        {

            this.items = items;

        }

​

        public void AddItem(Item item)

        {

            this.items.Add(item);

        }

        public void RemoveItem(Item item)

        {

            this.items.Remove(item);

        }

        public bool IsContains(Item item)

        {

            return this.items.Contains(item);

        }

        public int GetitemSCount()

        {

            return this.items.Count;

        }

        public int GetItemsCountAll()

        {

            int count = GetitemSCount();

            foreach(var item in this.items)

            {

                if(item.items?.GetitemSCount() > 0)

                {

                    count += item.items.GetItemsCountAll();

                }

            }

            return count;

        }

        public void ShowItemInfo(Item item, int tabCount = 0)

        {

            Console.WriteLine($"{TabCountPrint(tabCount)}| id: {item._id} | type: {item._type} | amount: {item._amount} | create_time: {item._create_time} | itemsCount: {item.items?.GetitemSCount() ?? 0}");

        }

        public void ShowItemInfo(int index)

        {

            ShowItemInfo(this.items[index]);

        }

        public void ShowItemsList(int tabCount = 0)

        {   

            string tabStr = TabCountPrint(tabCount);

            Console.WriteLine(tabStr + "| invetory > owner_id: " + ownerInfo.id + " | owner_type: " + ownerInfo.type);

            foreach(var item in this.items)

            {

                ShowItemInfo(item, tabCount);

                if(item.items?.GetitemSCount() > 0)

                {

                    item.items.ShowItemsList(tabCount + 1);

                }

            }

            Console.WriteLine(tabStr + "| ItemsCount: " + GetitemSCount());

            if(tabCount == 0)

                Console.WriteLine(tabStr + "| ItemsCountAll: " + GetItemsCountAll());

            if(ownerInfo.type != InventoryOwnerType.InventoryItem)

                Console.WriteLine();

        }

    }

    public static void Main()

    {

        Inventory inventory = new Inventory(1, InventoryOwnerType.Player) 

        {

            items = new List<Item> 

            {

                new Item(1, 10, 2) 

                {

                    items = new Inventory

                    (

                        new List<Item>

                        {

                            new Item(6, 60, 12),

                            new Item(7, 70, 14),

                            new Item(8, 80, 16)

                            {

                                items = new Inventory

                                (

                                    new List<Item>

                                    {

                                        new Item(9, 90, 18),

                                        new Item(10, 100, 20),

                                        new Item(11, 110, 22)

                                    }

                                )

                            },

                        }

                    )

                },

                new Item(2, 20, 4),

                new Item(3, 30, 6),

                new Item(4, 40, 8),

                new Item(5, 50, 10)

            }

        };

        inventory.ShowItemsList();

        // ----

        Inventory inventory1 = new Inventory(2, InventoryOwnerType.Player);

        inventory1.AddItem(new Item(1, 50, 10));    

        inventory1.AddItem(new Item(2, 60, 12));

        inventory1.AddItem(new Item(3, 70, 14));

        inventory1.items[0].items.AddItem(new Item(3, 70, 14));

        inventory1.ShowItemsList();

        /*

        var inventory = new Inventory

        (

            new Item(1, 10, 2),

            new Item(2, 20, 4), 

            new Item(3, 30, 6)

        );

        */

    }

}

​

​