using System;
using System.Collections;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using BITKit;
using BITKit.Entities;
using BITKit.SubSystems.Quest;
using Cysharp.Threading.Tasks;
using kcp2k;
using Quadtree;
using Quadtree.Items;
using UnityEngine;
using UnityEngine.AI;
using YooAsset;
using Random = UnityEngine.Random;

namespace BITFALL.GameMode
{
	public class NpcSpawnService : MonoBehaviour
	{
		private class MyInfo:IItem<MyInfo,Node<MyInfo>>
		{
			public int Id { get; } = BITApp.Count;
			public InfoNpcStart Info { get; set; }
			public Bounds GetBounds() => new(Info.Position, Vector3.one);
			public Node<MyInfo> ParentNode { get; set; }
			public void QuadTree_Root_Initialized(IQuadtreeRoot<MyInfo, Node<MyInfo>> root)
			{
			}
		}
		private struct NpcInfo
		{
			public int Id;
			public Transform Transform;
			public Renderer Renderer;
			public string Name;
			public IHealth Health;
			public Entity Entity;
		}
		[SerializeReference, SubclassSelector] private ITicker ticker;
		[SerializeReference, SubclassSelector] private ITicker clearRepeatTick;
		[SerializeField] private Vector3 spawnSize = Vector3.one;
		[SerializeField, ReadOnly] private int spawnCount;
		[SerializeField, ReadOnly] private int tickCount;

		private readonly QuadtreeRoot<MyInfo, Node<MyInfo>> _quadtree = new(default,Vector3.one*2048);
		private bool _isBusy;
		
		private readonly ConcurrentDictionary<string,Transform> _prefabs=new();

		private readonly Dictionary<int,NpcInfo> actives=new();
		private readonly List<int> _removeList = new();
		private readonly List<MyInfo> _myInfos = new();
		private readonly HashSet<int> _usedNodes = new();
		private void Start()
		{
			ticker.Add(OnTick);
			clearRepeatTick?.Add(ClearRepeat);
			NodeQuery.AddRegisterListener(typeof(InfoNpcStart), OnNpcInfoRegister);
			NodeQuery.AddUnregisterListener(typeof(InfoNpcStart), OnNpcInfoUnRegister);
			destroyCancellationToken.Register(Dispose);
			
			foreach (var x in NodeQuery.Query<InfoNpcStart>())
			{
				OnNpcInfoRegister(x);
			}
		}
		private void Dispose()
		{
			clearRepeatTick?.Remove(ClearRepeat);
			NodeQuery.RemoveRegisterListener(typeof(InfoNpcStart), OnNpcInfoRegister);
			NodeQuery.RemoveUnregisterListener(typeof(InfoNpcStart), OnNpcInfoUnRegister);
			ticker.Remove(OnTick);
		}
		private void ClearRepeat(float obj)
		{
			_usedNodes.Clear();
		}
		private void OnNpcInfoRegister(object obj)
		{
			_quadtree.Insert(new MyInfo{Info = (InfoNpcStart) obj});
		}
		private void OnNpcInfoUnRegister(object obj)
		{
			_quadtree.Remove(new MyInfo{Info = (InfoNpcStart) obj});
		}
		private async void OnTick(float obj)
		{
			try
			{
				if (_isBusy || enabled is false) return;
				tickCount++;
				_isBusy = true;
				var cameraPosition = Camera.main.transform.position;
				await UniTask.SwitchToThreadPool();

				_myInfos.Clear();

				float ByDistance(MyInfo y)
				{
					return Vector3.Distance(y.GetBounds().center, cameraPosition);
				}

				foreach (var x in _quadtree.Find(new Bounds(cameraPosition, spawnSize)).OrderBy(ByDistance))
				{
					if (clearRepeatTick is not null)
					{
						if (_usedNodes.Add(x.Id) is false) continue;
					}

					var distance = Vector3.Distance(cameraPosition, x.Info.Position);
					if (8 > distance) continue;
					if( 32 < distance) continue;
					if( x.Info.Position.y - cameraPosition.y > 3) continue;
					_myInfos.Add(x);
				}
				await UniTask.SwitchToMainThread();
				if (destroyCancellationToken.IsCancellationRequested) return;

				foreach (var (id, info) in actives)
				{
					if (!info.Transform || info.Health.IsAlive is false)
					{
						_removeList.Add(id);
						continue;
					}
					var infoPos = info.Transform.position;
					
					switch (Vector3.Distance(infoPos, cameraPosition), info.Renderer.isVisible)
					{
						case (> 64, _):
						case (> 32, false):
							//info.Health.HealthPoint = -1;
							_removeList.Add(id);
							break;
						default:
							if (Mathf.Abs(infoPos.y - cameraPosition.y) > 6)
							{
								_removeList.Add(id);
							}
							break;
					}
				}
				foreach (var x in _removeList)
				{
					var info = actives[x];
					if (info.Transform)
					{
						if (info.Transform.TryGetComponent<IPoolObject>(out var pool))
						{
							pool.EnabledHandle.RemoveElement(this);
						}
					}
					actives.Remove(x);
				}
				_removeList.Clear();

				foreach (var info in _myInfos)
				{
					var prefab = _prefabs.GetOrAdd(info.Info.Name, OnAdd);
					var prefabName = prefab.name;
					if (destroyCancellationToken.IsCancellationRequested) return;
					if (PoolService.TryGet(prefab, out var x) is false)
					{
						_isBusy = false;
						return;
					}
					
				
					
					spawnCount++;
					x.TryGetComponent<IHealth>(out var health);
						var pos = info.Info.Position;
						pos.x += Random.Range(-1, 1);
						pos.z += Random.Range(-1, 1);
						health.HealthPoint = health.MaxHealthPoint;
						x.SetPositionAndRotation(pos, info.Info.Rotation);
						if (x.TryGetComponent<NavMeshAgent>(out var agent))
						{
							if (agent.enabled)
							{
								agent.enabled = false;
								agent.enabled = true;
								agent.SetDestination(pos);
								agent.nextPosition = pos;
							}
						}
						var npcInfo = new NpcInfo
						{
							Id = spawnCount,
							Transform = x,
							Renderer = x.GetComponentInChildren<Renderer>(true),
							Entity = x.GetComponent<Entity>(),
							Name = prefabName,
							Health = health,
						};
						actives.Add(npcInfo.Id, npcInfo);
						health.OnSetAlive += OnSetAlive;

						if (x.TryGetComponent<IPoolObject>(out var pool))
						{
							pool.EnabledHandle.AddElement(this);
						}

						continue;

						void OnSetAlive(bool alive)
						{
							if(alive)return;
							health.OnSetAlive -= OnSetAlive;
							actives.TryRemove(npcInfo.Id);
							if (x.TryGetComponent<IPoolObject>(out var o))
							{
								o.EnabledHandle.RemoveElement(this);
							}
						}
				}
				_isBusy = false;
			}
			catch (Exception e)
			{
				BIT4Log.LogException(e);
				_isBusy = false;
			}
		}

		

		private Transform OnAdd(string arg)
		{
			var asset = YooAssets.LoadAssetAsync<GameObject>(arg);
			asset.WaitForAsyncComplete();
			var prefab = asset.AssetObject.As<GameObject>().transform;
			_prefabs.TryAdd(arg, prefab);
			return prefab;
		}
		
		private void Reset()
		{
			foreach (var x in actives.Values.ToArray())
			{
				x.Health.HealthPoint = -1;
			}
		}
	}
}