/*
 Sog 游戏基础库
 2016 by zouwei
 */

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Threading.Tasks;

using Sog;
using Sog.Gate;

namespace Gate
{
    // 客户端连接的路由策略，可定制一定路由规则
    public class ServerRoute : BaseReloadableService
    {
        private ServerApp m_app;

        private long m_selectBackEndSeq = 0;

        //接口实现
        public override int GetServiceType()
        {
            return GateServiceType.ServerRoute;
        }

        //接口实现
        public override void Dispose()
        {
            m_app = null;
        }

        public ServerRoute(ServerApp app)
        {
            m_app = app;
        }

        /// <summary>
        /// 选择后端逻辑服务器
        /// </summary>
        /// <param name="info"></param>
        /// <returns></returns>
        public uint SelectBackEndServerID(GateClientInfo info)
        {
            //如果之前已经有了，直接采用
            if(info.LinkServerID != 0)
            {
                return info.LinkServerID;
            }

            //随机选一个
            int backEndType = GateServerUtils.GetServerConfig().backEndServerType;

            uint[] serverIDs = m_app.GetCluster().GetRemoteAppID(backEndType);
            if(serverIDs.Length == 0)
            {
                TraceLog.Error("ServerRoute.SelectBackEndServerID no valid logic server id, serverType {0}", backEndType);
                return 0;
            }

            uint serverId = 0;
            int myType = ServerIDUtils.GetServerType(m_app.ServerID);
            int myInstId = (int)ServerIDUtils.GetInstanceID(m_app.ServerID);
            //游戏服务器尽量选instid相同的，这样保证第一次选择就是正确的game，不用切
            if (myType == (int)ServerType.GameGate && myInstId <= serverIDs.Length)
            {
                serverId = serverIDs[myInstId - 1];
            }
            else
            {
                int index = (int)(m_selectBackEndSeq % serverIDs.Length);
                serverId = serverIDs[index];
                m_selectBackEndSeq++;
            }

            TraceLog.Trace("SelectBackEndServerID SelectPlayerGameGate myInstId {0} serverId {1}", myInstId, ServerIDUtils.IDToString(serverId));

            info.LinkServerID = serverId;

            return info.LinkServerID;
        }

        public void RouteBackEndServer(uint remoteAppID, MessageData message, GateMsgHeader header)
        {
            GateClientInfo info = GateServerUtils.GetGateClientService().GetGateClientInfoThreadSafe(header.SessionID);
            if (info == null)
            {
                TraceLog.Debug("ServerRoute.RouteBackEndServer session {0} message ,but can not find session,drop msg"
                    , header.SessionID);
                return;
            }

            if (info.State != GameClientState.Noraml)
            {
                TraceLog.Debug("ServerRoute.RouteBackEndServer session {0} message ,but session stat is {1},drop msg"
                    , header.SessionID, GameClientState.Noraml);
                return;
            }

            uint routeServerID = message.Header.ServerID;

            TraceLog.Debug("ServerRoute.RouteBackEndServer session {0} src server {1} change to dst server {2}"
                , header.SessionID, ServerIDUtils.IDToString(remoteAppID), ServerIDUtils.IDToString(routeServerID));

            //判断下route的目标服务器合不合法
            int backEndType = GateServerUtils.GetServerConfig().backEndServerType;

            uint[] serverIDs = m_app.GetCluster().GetRemoteAppID(backEndType);
            bool valid = false;
            foreach (uint serverId in serverIDs)
            {
                if (serverId == routeServerID)
                {
                    valid = true;
                    break;
                }
            }

            if (valid == false)
            {
                TraceLog.Error("ServerRoute.RouteBackEndServer session {0} message ,but route serverid invalid {1}"
                    , header.SessionID, routeServerID);
                return;
            }

            //改后端服务器地址
            info.LinkServerID = routeServerID;

            string ip = "0.0.0.0";
            if (info.Session != null && info.Session.RemoteEndPoint != null)
            {
                try
                {
                    ip = info.Session.RemoteEndPoint.ToString().Split(':')[0];
                }
                catch (Exception)
                {

                }

            }


            //先通知一个connected
            GateClientConnectedReq req = new GateClientConnectedReq();
            req.IPAddress = ip;
            GateServerUtils.GetServerMsgTrans().NotifyServerClientConnected(info, req);

            //转发消息,判断一下是不是有实际消息需要转发，没有就算了
            if (message.Header.Length > GateMsgHeaderPacker.GetLength())
            {
                TraceLog.Debug("ServerRoute.RouteBackEndServer session {0} trans route msg to new server"
                    , header.SessionID);

                //这里面本来是GateMsgOpCode.Route，直接改成Trans就可以了
                GateMsgHeaderPacker.RawSetGateMsgHeadOpCode(message.Buffer.Data, GateMsgOpCode.Trans);
                //拷贝一个新的，要不然内存管理会出问题
                MessageData newMessage = new MessageData();
                newMessage.Header = message.Header;
                newMessage.MallocData(message.Buffer.Length);

                Buffer.BlockCopy(message.Buffer.Data, 0, newMessage.Buffer.Data, 0, newMessage.Buffer.Length);

                m_app.GetCluster().Send(info.LinkServerID, newMessage);


            }

        }

    }
}