using Microsoft.AspNetCore.Connections;
using Newtonsoft.Json;
using RabbitMQ.Client;
using System.Collections.Concurrent;
using System.Text;
using System.Threading.Channels;
using static Microsoft.EntityFrameworkCore.DbLoggerCategory.Database;

namespace AmrControl.mq
{
    /// <summary>
    /// rabbitmq服务
    /// </summary>
    public class RabbitmqService : IRabbitmqService, IDisposable
    {

        private const string EXCHANGE_NAME = "wcs-exchange";

        private const string COMMON_TOPIC = "wcs-handle";
        /// <summary>
        /// 确认处理
        /// </summary>
        private static ConcurrentDictionary<ulong, TaskCompletionSource<byte>> outstandingConfirms = new ConcurrentDictionary<ulong, TaskCompletionSource<byte>>();
        /// <summary>
        /// 配置文件
        /// </summary>
        private readonly IConfiguration _configuration;
        /// <summary>
        /// 启动状态
        /// </summary>
        private volatile bool started;
        /// <summary>
        /// 连接工厂
        /// </summary>
        private ConnectionFactory factory;
        /// <summary>
        /// mq连接
        /// </summary>
        private IConnection _connection;
        /// <summary>
        /// 通道处理
        /// </summary>
        private IModel _channel;

        private static volatile RabbitmqService instance = null;
        public RabbitmqService(IConfiguration configuration) 
        {
            this._configuration = configuration;
            instance = this;
        }
        /// <summary>
        /// 获取实例
        /// </summary>
        /// <returns></returns>
        public static RabbitmqService getInstance()
        {
            return instance;
        }

        public void Dispose()
        {
            started = false;
            _channel?.Dispose();
            _connection?.Dispose();
        }

        public void Init()
        {
            if(!started)
            {
                started = true;
                factory = new ConnectionFactory()
                {
                    HostName = _configuration["mq:host"],
                    Port = int.Parse(_configuration["mq:port"]),
                    UserName = _configuration["mq:username"],
                    Password = _configuration["mq:password"],
                    //ClientProperties = new Dictionary<string, object>
                    //{
                    //    ["publisher-confirm-type"] = "correlated",
                    //    ["publisher-returns"] = true
                    //}
                };
                connect();
                checkAndReConn();
            }
            
        }
        /// <summary>
        /// 启动连接检查
        /// </summary>
        /// <returns></returns>
        async Task checkAndReConn()
        {
            while(started)
            {
                if(!isConnect())
                {
                    connect();
                }
                await Task.Delay(TimeSpan.FromSeconds(10));
            }
        }
        /// <summary>
        /// 判断连接状态是否正常
        /// </summary>
        /// <returns></returns>
        private bool isConnect()
        {
            return _connection != null && _connection.IsOpen && _channel != null && _channel.IsOpen;
        }
        /// <summary>
        /// 连接rabbitmq
        /// </summary>
        private void connect()
        {
            try
            {
                _connection = factory.CreateConnection();
                _channel = _connection.CreateModel();
                //声明交换机,以发布订阅方式发送消息
                _channel.ExchangeDeclare(EXCHANGE_NAME, ExchangeType.Topic, true);
            } catch
            {
                Console.WriteLine("connect failed!");
            }
            
        }

        public void SendMsg<T>(string topic, MqMessage<T> msg)
        {
            //允许消息持久化到磁盘
            var properties = _channel.CreateBasicProperties();
            if(msg.msgType != 3)
            {
                //工位消息不做持久化处理
                properties.Persistent = true;
            }
            //启用发布确认模式
            _channel.ConfirmSelect();
            _channel.BasicPublish(EXCHANGE_NAME, topic, properties, Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(msg)));

            // 添加消息发送失败的回调函数
            _channel.BasicReturn += (sender, args) =>
            {
                Console.WriteLine("消息找不到投送的queue,投送失败，消息内容: {0}", Encoding.UTF8.GetString(args.Body.ToArray()));
            };

            // 添加消息确认回调函数
            _channel.BasicAcks += (sender, args) =>
            {
                Console.WriteLine("消息发送成功");
            };
            //拒绝处理监听
            _channel.BasicNacks += (sender, ea) =>
            {
                Console.WriteLine("客户端拒绝接收消息");
            };
        }
        /// <summary>
        /// 通用topic
        /// </summary>
        /// <returns></returns>
        public string getCommonTopic()
        {
            return COMMON_TOPIC;
        }

        public void SendMsg<T>(MqMessage<T> msg)
        {
            SendMsg(COMMON_TOPIC, msg);
        }
    }
}