using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Configuration;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Newtonsoft.Json;
using StackExchange.Redis;

namespace ProjectBase.Data.Redis
{
    public class RedisConnection
    {
        // 系统自定义Key前缀
        public static readonly string SysCustomKey = ConfigurationManager.AppSettings["redisKey"] ?? "";

        // "127.0.0.1:6379,allowadmin=true
        private static readonly string RedisConnectionString = ConfigurationManager.ConnectionStrings["RedisExchangeHosts"].ConnectionString;

        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;
        }
    }
}