using System;
using System.Collections.Generic;
using PhxhSDK;

namespace Framework
{
    public partial class EventManager : Singlenton<EventManager>
    {
        private Dictionary<EventName, HashSet<Delegate>> _eventDict = new Dictionary<EventName, HashSet<Delegate>>();

        private Action<EventName> _afterSendCallBack;

        public event Action<EventName> AfterSendCallBack
        {
            add => _afterSendCallBack += value;
            remove => _afterSendCallBack -= value;
        }

        public const int MAX_EVENT_STACK = 3;

        public void Register<T>(EventName eventName, Action<T> action)
        {
            try
            {
                if (action == null)
                {
                    return;
                }

                if (!_eventDict.ContainsKey(eventName))
                {
                    _eventDict[eventName] = new HashSet<Delegate>();
                }

                _eventDict[eventName].Add(action);
            }
            catch (Exception e)
            {
                DebugUtil.LogError("EventSystem.Register<T> : {0}, {1}", eventName, e);
            }
        }

        public void Register(EventName eventName, Action action)
        {
            try
            {
                if (action == null)
                {
                    return;
                }

                if (!_eventDict.ContainsKey(eventName))
                {
                    _eventDict[eventName] = new HashSet<Delegate>();
                }

                _eventDict[eventName].Add(action);
            }
            catch (Exception e)
            {
                DebugUtil.LogError("EventSystem.Register : {0}, {1}", eventName, e);
            }
        }

        public void Unregister(EventName eventName, Action action)
        {
            try
            {
                if (action == null)
                {
                    return;
                }

                if (!_eventDict.ContainsKey(eventName))
                {
                    return;
                }

                _eventDict[eventName].Remove(action);
            }
            catch (Exception e)
            {
                DebugUtil.LogError("EventSystem.Unregister : {0}, {1}", eventName, e);
            }
        }

        public void Unregister<T>(EventName eventName, Action<T> action)
        {
            try
            {
                if (action == null)
                {
                    return;
                }

                if (!_eventDict.ContainsKey(eventName))
                {
                    return;
                }

                _eventDict[eventName].Remove(action);
            }
            catch (Exception e)
            {
                DebugUtil.LogError("EventSystem.Unregister<T> : {0}, {1}", eventName, e);
            }
        }

        public void Send<T>(EventName eventName, T arg)
        {
            try
            {
                _eventSendingStack.Push(eventName);
                if (EventStackReachMax(_eventSendingStack.Count))
                {
                    DebugUtil.LogError("EventSystem.Send<{0}> : {1}, {2} reach max event count {3}", typeof(T).Name, eventName, arg, MAX_EVENT_STACK);
                    foreach (var eventNameInStack in _eventSendingStack)
                    {
                        DebugUtil.LogError("Event Stack : {0}", eventNameInStack);
                    }
                    return;
                }

                //DebugUtil.Log($"EventSystem.Send<T> : {eventName}");
                if (!_eventDict.ContainsKey(eventName))
                {
                    _eventSendingStack.Pop();
                    _afterSendCallBack?.Invoke(eventName);
                    return;
                }


                var actions = _eventDict[eventName];
                var tempExecuteList = GetTempExecuteList();
                tempExecuteList.AddRange(actions);
                using var e = tempExecuteList.GetEnumerator();
                while (e.MoveNext())
                {
                    if (e.Current is Action<T> actionT)
                    {
                        actionT(arg);
                    }
                    //空参数函数也要调用
                    if (e.Current is Action action)
                    {
                        action();
                    }
                }

                ReCycleTempExecuteList(tempExecuteList);

                _afterSendCallBack?.Invoke(eventName);
                _eventSendingStack.Pop();
            }
            catch (Exception exception)
            {
                DebugUtil.LogError("EventSystem.Send<T> : {0}, {1}", eventName, exception);
            }
        }

        public void Send(EventName eventName)
        {
            try
            {
                if (!_eventDict.ContainsKey(eventName))
                {
                    _afterSendCallBack?.Invoke(eventName);
                    return;
                }

                var actions = _eventDict[eventName];
                var tempExecuteList = GetTempExecuteList();
                tempExecuteList.AddRange(actions);
                foreach (var action in tempExecuteList)
                {
                    if (action is Action actionT)
                    {
                        actionT();
                    }
                }
                
                ReCycleTempExecuteList(tempExecuteList);
                _afterSendCallBack?.Invoke(eventName);
            }
            catch (Exception e)
            {
                DebugUtil.LogError("EventSystem.Send : {0}, {1}", eventName, e);
            }
        }


        private bool EventStackReachMax(int current)
        {
            if (current > MAX_EVENT_STACK)
            {
                return true;
            }

            return false;
        }
    }
}