using System;
using System.Collections;
using System.Collections.Concurrent;
using System.Collections.Generic;
using AYellowpaper.SerializedCollections;
using UnityEngine;

namespace BITKit
{
	public class PoolService : MonoBehaviour
	{
		private static readonly ConcurrentDictionary<string, Transform> _Prefabs = new();
		private static readonly ConcurrentDictionary<string,UnityPool<Transform>> _Pools = new();
		public static Transform Get(Transform prefab)
		{
			_Prefabs.TryAdd(prefab.name, prefab);
			var pool = _Pools.GetOrAdd(prefab.name, CreatePool);
			return pool.Get();
		}
		public static bool TryGet(Transform prefab, out Transform instance)
		{
			_Prefabs.TryAdd(prefab.name, prefab);
			var pool = _Pools.GetOrAdd(prefab.name, CreatePool);
			instance = null;
			if (pool.InstanceCount>=pool.DefaultCapacity) return false;
			instance = pool.Get();
			return true;
		}
		public static void Release(string name,Transform instance)
		{
			var pool = _Pools.GetOrAdd(name, CreatePool);
			pool.Return(instance);
		}
		private static UnityPool<Transform> CreatePool(string name)
		{
			var pool = new UnityPool<Transform>
			{
				Prefab = _Prefabs[name],
				OnReturn = null,
			};
			return pool;
		}
		[SerializeField] private SerializedDictionary<Transform,int> initialCapacity;

		private void Start()
		{
			foreach (var (key, value) in initialCapacity)
			{
				var pool = new UnityPool<Transform>
				{
					Prefab = key,
					DefaultCapacity = value,
					Root = transform,
					OnReturn = null,
				};
				_Prefabs.TryAdd(key.name, key);
				_Pools.TryAdd(key.name, pool);
				var list = new List<Transform>();
				for (var i = 0; i < pool.DefaultCapacity; i++)
				{
					list.Add(pool.Get());
				}
				foreach (var x in list)
				{
					x.gameObject.SetActive(false);
					pool.Return(x);
				}
			}
		}

		private void OnDestroy()
		{
			_Prefabs.Clear();
			_Pools.Clear();
		}
	}

}