using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class EventCenter
{
    private static Dictionary<EventType, Delegate> m_EventTable = new Dictionary<EventType, Delegate>();

    //添加监听
    private static void OnListenerAdding(EventType eventType,Delegate callBack)
    {
        if (!m_EventTable.ContainsKey(eventType))
        {
            m_EventTable.Add(eventType, null);
        }
        Delegate d = m_EventTable[eventType];
        if (d != null && d.GetType() != callBack.GetType())
        {
            throw new Exception(string.Format("尝试为事件{0}添加不同类型的委托，当前事件所对应的委托是{1},要添加的委托类型为{2}", eventType, d.GetType(), callBack.GetType()));
        }
    }
    //移除监听
    private static void OnListenerRemoving(EventType eventType,Delegate callBack)
    {
        if (m_EventTable.ContainsKey(eventType))
        {
            Delegate d = m_EventTable[eventType];
            if (d == null)
            {
                throw new Exception(string.Format("移除监听错误：事件{0}没有对应的委托", eventType));
            }
            else if (d.GetType() != callBack.GetType())
            {
                throw new Exception(string.Format("移除监听错误：尝试为事件{0}移除不同类型的委托，当前委托类型为{1},要移除的类型为{2}", eventType, d.GetType(), callBack.GetType()));
            }
        }
        else
        {
            throw new Exception(string.Format("移除监听错误：没有事件码{0}", eventType));
        }
    }
    //移除监听后，刷新监听事件列表
    public static void OnListenerRemoeved(EventType eventType)
    {
        if (m_EventTable[eventType] == null)
        {
            m_EventTable.Remove(eventType);
        }
    }

    //六种参数数量的添加监听方法
    //no parameters没有参数
    public static void AddListener(EventType eventType,CallBack callBack)
    {
        OnListenerAdding(eventType, callBack);
         m_EventTable[eventType] = (CallBack)m_EventTable[eventType] + callBack;
    }
    //Single parametener一个参数
    public static void AddListener<T>(EventType eventType, CallBack<T> callBack)
    {
        OnListenerAdding(eventType, callBack);
        m_EventTable[eventType] = (CallBack<T>)m_EventTable[eventType] + callBack;
    }
    //two parametener两个参数
    public static void AddListener<T,X>(EventType eventType, CallBack<T,X> callBack)
    {
        OnListenerAdding(eventType, callBack);
        m_EventTable[eventType] = (CallBack<T,X>)m_EventTable[eventType] + callBack;
    }
    //three parametener三个参数
    public static void AddListener<T, X, Y>(EventType eventType, CallBack<T, X, Y> callBack)
    {
        OnListenerAdding(eventType, callBack);
        m_EventTable[eventType] = (CallBack<T, X, Y>)m_EventTable[eventType] + callBack;
    }
    //four parametener四个参数
    public static void AddListener<T, X, Y, Z>(EventType eventType, CallBack<T, X, Y, Z> callBack)
    {
        OnListenerAdding(eventType, callBack);
        m_EventTable[eventType] = (CallBack<T, X, Y, Z>)m_EventTable[eventType] + callBack;
    }
    //five parametener五个参数
    public static void AddListener<T, X, Y, Z, W>(EventType eventType, CallBack<T, X, Y, Z, W> callBack)
    {
        OnListenerAdding(eventType, callBack);
        m_EventTable[eventType] = (CallBack<T, X, Y, Z, W>)m_EventTable[eventType] + callBack;
    }

    //六种参数数量情况下的事件移除方法
    //no parameters
    public static void RemoveListener(EventType eventType,CallBack callBack)
    {
        OnListenerRemoving(eventType, callBack);
        m_EventTable[eventType] = (CallBack)m_EventTable[eventType] - callBack;
        OnListenerRemoeved(eventType);
    }
    //Single parameters
    public static void RemoveListener<T>(EventType eventType, CallBack<T> callBack)
    {
        OnListenerRemoving(eventType, callBack);
        m_EventTable[eventType] = (CallBack<T>)m_EventTable[eventType] - callBack;
        OnListenerRemoeved(eventType);
    }
    //two parameters
    public static void RemoveListener<T,X>(EventType eventType, CallBack<T,X> callBack)
    {
        OnListenerRemoving(eventType, callBack);