using learun.util;
using StackExchange.Redis;
using System;
using System.Collections.Concurrent;

namespace learun.cache
{
	/// <summary>
	/// 版 本 EasyCode EC管理后台
	/// Copyright (c) 2019-present EC管理有限公司
	/// 创建人：tobin
	/// 日 期：2019.09.02
	/// 描 述：Redis连接帮助类
	/// </summary>
	public class RedisConnectionHelp
	{
		/// <summary>
		/// 系统自定义Key前缀
		/// </summary>
		public static readonly string SysCustomKey = ConfigHelper.GetConfig().RedisPrev ?? "";

		//"127.0.0.1:6379,allowadmin=true
		private static readonly string RedisConnectionString = ConfigHelper.GetConfig().RedisExchangeHosts ?? "127.0.0.1:6379,allowadmin=true";

		private static readonly object Locker = new object();
		private static ConnectionMultiplexer _instance;
		private static readonly ConcurrentDictionary<string, ConnectionMultiplexer> ConnectionCache = new ConcurrentDictionary<string, ConnectionMultiplexer>();

		/// <summary>
		/// 单例获取
		/// </summary>
		public static ConnectionMultiplexer Instance
		{
			get
			{
				if (_instance == null)
				{
					lock (Locker)
					{
						if (_instance == null || !_instance.IsConnected)
						{
							_instance = GetManager();
						}
					}
				}
				return _instance;
			}
		}

		/// <summary>
		/// 缓存获取
		/// </summary>
		/// <param name="connectionString"></param>
		/// <returns></returns>
		public static ConnectionMultiplexer GetConnectionMultiplexer(string connectionString)
		{
			if (!ConnectionCache.ContainsKey(connectionString))
			{
				ConnectionCache[connectionString] = GetManager(connectionString);
			}
			return ConnectionCache[connectionString];
		}

		private static ConnectionMultiplexer GetManager(string connectionString = null)
		{
			connectionString = connectionString ?? RedisConnectionString;
			var connect = ConnectionMultiplexer.Connect(connectionString);

			//注册如下事件
			connect.ConnectionFailed += MuxerConnectionFailed;
			connect.ConnectionRestored += MuxerConnectionRestored;
			connect.ErrorMessage += MuxerErrorMessage;
			connect.ConfigurationChanged += MuxerConfigurationChanged;
			connect.HashSlotMoved += MuxerHashSlotMoved;
			connect.InternalError += MuxerInternalError;

			return connect;
		}

		#region 事件

		/// <summary>
		/// 配置更改时
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private static void MuxerConfigurationChanged(object sender, EndPointEventArgs e)
		{
			Console.WriteLine("Configuration changed: " + e.EndPoint);
		}

		/// <summary>
		/// 发生错误时
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private static void MuxerErrorMessage(object sender, RedisErrorEventArgs e)
		{
			Console.WriteLine("ErrorMessage: " + e.Message);
		}

		/// <summary>
		/// 重新建立连接之前的错误
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private static void MuxerConnectionRestored(object sender, ConnectionFailedEventArgs e)
		{
			Console.WriteLine("ConnectionRestored: " + e.EndPoint);
		}

		/// <summary>
		/// 连接失败 ， 如果重新连接成功你将不会收到这个通知
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private static void MuxerConnectionFailed(object sender, ConnectionFailedEventArgs e)
		{
			Console.WriteLine("重新连接：Endpoint failed: " + e.EndPoint + ", " + e.FailureType + (e.Exception == null ? "" : (", " + e.Exception.Message)));
		}

		/// <summary>
		/// 更改集群
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private static void MuxerHashSlotMoved(object sender, HashSlotMovedEventArgs e)
		{
			Console.WriteLine("HashSlotMoved:NewEndPoint" + e.NewEndPoint + ", OldEndPoint" + e.OldEndPoint);
		}

		/// <summary>
		/// redis类库错误
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private static void MuxerInternalError(object sender, InternalErrorEventArgs e)
		{
			Console.WriteLine("InternalError:Message" + e.Exception.Message);
		}

		#endregion 事件
	}
}