using OnlineStore;

using DL.Utils;
using log4net;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Reflection;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace DL.Com
{
    public class UdpServer
    {

        static readonly ILog log = LogManager.GetLogger(MethodBase.GetCurrentMethod()?.DeclaringType);
        private Thread m_serverThread;
        private Socket udpServer;
        public delegate void ReviceMsg(EndPoint address, string Msg);
        /// <summary>
        /// 接受到数据事件
        /// </summary>
        public event ReviceMsg ReviceMsgEvent;

        private bool isRun = true;
        private int serverPort;
        private void logLocalIp()
        {
            string[] addresses = GetLocalAddresses();
            string iplist = crc.GetString("Res0038","本机IP:[");
            if (addresses.Length > 0)
            {
                for (int i = 0; i < addresses.Length; i++)
                {
                    if (addresses.Length != 0)
                    {
                        iplist = iplist + " " + addresses[i];
                    }
                }
            }
            LogUtil.Info(iplist + "]",log);
        }
        public UdpServer(int m_serverPort)
        {
            serverPort = m_serverPort;
        }

        /// <summary>
        /// 开始服务
        /// </summary>
        public bool Start()
        {
            try
            {
                IPEndPoint ipep = new IPEndPoint(IPAddress.Any, serverPort);//定义一网络端点
                udpServer = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);//定义一个Socket
                udpServer.Bind(ipep);//Socket与本地的一个终结点相关联

                m_serverThread = new Thread(new ThreadStart(ReceiveData));
                m_serverThread.Start();
                logLocalIp();
                isRun = true;
                return true;
            }

            catch (Exception ex)
            {
                LogUtil.Error("启动udpserver出错" ,log,ex);
            }
            return false;
        }

        /// <summary>
        /// 停止服务
        /// </summary>
        public bool Stop()
        {
            try
            {
                isRun = false;
                m_serverThread.Interrupt(); // 线程终止
                udpServer.Close(); // Socket Close  
                return true;
            }
            catch (Exception ex)
            {
                LogUtil.Error("Stop Udpserver出错",log,ex);
            }
            return false;
        }
        private StringBuilder sb = new StringBuilder();             //这个是用来保存：接收到了的，但是还没有结束的消息
        private int receiveBufferSize = 1024;
        /// <summary>
        /// 结束符
        /// </summary>
        public string terminateString = "\r";
        private void ReceiveData()
        {
            try
            {

                IPEndPoint sender = new IPEndPoint(IPAddress.Any, 0);//定义要发送的计算机的地址
                EndPoint Remote = (EndPoint)(sender);//

                while (true)
                {
                    byte[] buffer = new byte[receiveBufferSize];
                    int receivedSize = udpServer.ReceiveFrom(buffer, ref Remote);

                    if (receivedSize > 0)
                    {
                        string rawMsg = Encoding.ASCII.GetString(buffer, 0, receivedSize);
                        int rnFixLength = terminateString.Length;   //这个是指消息结束符的长度，此处为\r\n
                        for (int i = 0; i < rawMsg.Length;)               //遍历接收到的整个buffer文本
                        {
                            if (i <= rawMsg.Length - rnFixLength)
                            {
                                if (rawMsg.Substring(i, rnFixLength) != terminateString)//非消息结束符，则加入sb
                                {
                                    sb.Append(rawMsg[i]);
                                    i++;
                                }
                                else
                                {
                                    this.ReviceMsgEvent.Invoke(Remote, sb.ToString());//找到了消息结束符，触发消息接收完成事件
                                    sb = new StringBuilder();
                                    i += rnFixLength;
                                }
                            }
                            else
                            {
                                sb.Append(rawMsg[i]);
                                i++;
                            }
                        }
                    }
                    Thread.Sleep(500);
                }
            }
            catch (Exception ex)
            {
                LogUtil.Error("启动udpserver出错：" ,log,ex);
            }
        }
        /// <summary>
        /// 获取本机地址列表
        /// </summary>
        public string[] GetLocalAddresses()
        {
            // 获取主机名
            string strHostName = Dns.GetHostName();

            // 根据主机名进行查找
            IPHostEntry iphostentry = Dns.GetHostEntry(strHostName);

            string[] retval = new string[iphostentry.AddressList.Length];

            int i = 0;
            foreach (IPAddress ipaddress in iphostentry.AddressList)
            {
                if (ipaddress.AddressFamily != AddressFamily.InterNetworkV6)
                {
                    retval[i] = ipaddress.ToString();
                    i++;
                }
            }
            return retval;
        }

        public bool IsOnline(string addr = "")
        {
            return isRun;
        }

        public string GetAddr()
        {
            return $"{string.Join(",",GetLocalAddresses())}:{serverPort}";
        }
    }
}