using System;
using System.Collections.Generic;
using System.Runtime.CompilerServices;
using UnityEngine.Scripting;

namespace AlicizaX.Fsm.Runtime
{
    // 新增非泛型接口

    public struct FsmDebugInfo
    {
        public string FsmName;
        public string CurrentStateName;
        public int RegisteredStates;
    }

    [Preserve]
    public sealed class FsmModule : IFsmModule
    {
        private const int DefaultPoolSize = 64;
        private const int MaxPoolSize = 2048;

        // 按类型分组的对象池和活动实例
        private Dictionary<Type, Stack<IUltraFSM>> _fsmPools;
        private Dictionary<Type, List<IUltraFSM>> _activeFsms;

        public UltraFSM<TState> Create<TState>(string name, int initialCapacity = 8) where TState : struct, Enum
        {
            var stateType = typeof(TState);
            // 初始化存储结构
            if (!_fsmPools.ContainsKey(stateType))
            {
                _fsmPools.Add(stateType, new Stack<IUltraFSM>(DefaultPoolSize));
                _activeFsms.Add(stateType, new List<IUltraFSM>(DefaultPoolSize));
            }

            // 从池中获取或新建实例
            var fsm = _fsmPools[stateType].Count > 0
                ? (UltraFSM<TState>)_fsmPools[stateType].Pop()
                : new UltraFSM<TState>();

            fsm.Initialize(name, initialCapacity);
            _activeFsms[stateType].Add(fsm);
            return fsm;
        }

        public void Destroy<TState>(UltraFSM<TState> fsm) where TState : Enum
        {
            var stateType = typeof(TState);
            if (!_activeFsms.TryGetValue(stateType, out var activeList)) return;

            fsm?.Dispose();

            // 回收实例到池
            if (_fsmPools[stateType].Count < MaxPoolSize)
            {
                _fsmPools[stateType].Push(fsm);
            }

            // 从活动列表移除
            activeList.Remove(fsm);
        }

        public List<FsmDebugInfo> GetDebugInfo()
        {
            var list = new List<FsmDebugInfo>();
            foreach (var kvp in _activeFsms)
            {
                foreach (var fsm in kvp.Value)
                {
                    list.Add(new FsmDebugInfo
                    {
                        FsmName = fsm.Name,
                        CurrentStateName = fsm.StateName,
                    });
                }
            }

            return list;
        }

        void IModuleUpdate.Update(float elapseSeconds, float realElapseSeconds)
        {
            foreach (var kvp in _activeFsms)
            {
                foreach (var fsm in kvp.Value)
                {
                    fsm.Update(elapseSeconds);
                }
            }
        }

        void IModule.Dispose()
        {
            foreach (var pool in _fsmPools.Values)
            {
                while (pool.Count > 0)
                {
                    pool.Pop().Dispose();
                }
            }

            foreach (var activeList in _activeFsms.Values)
            {
                foreach (var fsm in activeList)
                {
                    fsm?.Dispose();
                }

                activeList.Clear();
            }

            _fsmPools.Clear();
            _activeFsms.Clear();
        }

        public int Priority => 0;

        void IModuleAwake.Awake()
        {
            _fsmPools = new();
            _activeFsms = new();
        }
    }
}