/*
* Copyright (c) Contributors, http://opensimulator.org/
* See CONTRIBUTORS.TXT for a full list of copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
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*       derived from this software without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS AS IS AND ANY
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using System;
using System.Collections;
using System.Collections.Generic;
using System.Net;
using System.Net.Sockets;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Tcp;
using System.Security.Authentication;

using libsecondlife;
using Nwc.XmlRpc;
using OpenSim.Framework;
using OpenSim.Framework.Communications;
using OpenSim.Framework.Console;
using OpenSim.Framework.Servers;
using OpenSim.Framework;
using OpenSim.Region.Communications.Local;

namespace OpenSim.Region.Communications.OGS1
{
    public class OGS1GridServices : IGridServices, IInterRegionCommunications
    {
        private LocalBackEndServices m_localBackend = new LocalBackEndServices();
        private Dictionary<ulong, RegionInfo> m_remoteRegionInfoCache = new Dictionary<ulong, RegionInfo>();

        public BaseHttpServer httpListener;
        public NetworkServersInfo serversInfo;
        public BaseHttpServer httpServer;

        /// <summary>
        /// 
        /// </summary>
        /// <param name="servers_info"></param>
        /// <param name="httpServe"></param>
        public OGS1GridServices(NetworkServersInfo servers_info, BaseHttpServer httpServe)
        {
            serversInfo = servers_info;
            httpServer = httpServe;
            httpServer.AddXmlRPCHandler("expect_user", this.ExpectUser);
            httpServer.AddXmlRPCHandler("check", this.PingCheckReply);

            this.StartRemoting();
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="regionInfo"></param>
        /// <returns></returns>
        public RegionCommsListener RegisterRegion(RegionInfo regionInfo)
        {
            Hashtable GridParams = new Hashtable();
            // Login / Authentication

            GridParams["authkey"] = serversInfo.GridSendKey;
            GridParams["UUID"] = regionInfo.RegionID.ToStringHyphenated();
            GridParams["sim_ip"] = regionInfo.ExternalHostName;
            GridParams["sim_port"] = regionInfo.InternalEndPoint.Port.ToString();
            GridParams["region_locx"] = regionInfo.RegionLocX.ToString();
            GridParams["region_locy"] = regionInfo.RegionLocY.ToString();
            GridParams["sim_name"] = regionInfo.RegionName;
            GridParams["http_port"] = serversInfo.HttpListenerPort.ToString();
            GridParams["remoting_port"] = NetworkServersInfo.RemotingListenerPort.ToString();
            GridParams["map-image-id"] = regionInfo.EstateSettings.terrainImageID.ToStringHyphenated();

            // Package into an XMLRPC Request
            ArrayList SendParams = new ArrayList();
            SendParams.Add(GridParams);

            // Send Request
            XmlRpcRequest GridReq = new XmlRpcRequest("simulator_login", SendParams);
            XmlRpcResponse GridResp = GridReq.Send(serversInfo.GridURL, 10000);
            Hashtable GridRespData = (Hashtable)GridResp.Value;

            Hashtable griddatahash = GridRespData;

            // Process Response
            if (GridRespData.ContainsKey("error"))
            {
                string errorstring = (string)GridRespData["error"];
                MainLog.Instance.Error("Unable to connect to grid: " + errorstring);
                return null;
            }

            return m_localBackend.RegisterRegion(regionInfo);
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="regionInfo"></param>
        /// <returns></returns>
        public List<SimpleRegionInfo> RequestNeighbours(uint x, uint y)
        {

            Hashtable respData = MapBlockQuery((int)x - 1, (int)y - 1, (int)x + 1, (int)y + 1);

            List<SimpleRegionInfo> neighbours = new List<SimpleRegionInfo>();

            foreach (ArrayList neighboursList in respData.Values)
            {
                foreach (Hashtable neighbourData in neighboursList)
                {
                    uint regX = Convert.ToUInt32(neighbourData["x"]);
                    uint regY = Convert.ToUInt32(neighbourData["y"]);
                    if ((x != regX) || (y != regY))
                    {

                        string simIp = (string)neighbourData["sim_ip"];

                        int port = Convert.ToInt32(neighbourData["sim_port"]);
                        string externalUri = (string)neighbourData["sim_uri"];

                        string externalIpStr = OpenSim.Framework.Util.GetHostFromDNS(simIp).ToString();
                        SimpleRegionInfo sri = new SimpleRegionInfo(regX, regY, simIp, port);
                        sri.RemotingPort = Convert.ToUInt32(neighbourData["remoting_port"]);
                        sri.RegionID = new LLUUID((string)neighbourData["uuid"]);

                        neighbours.Add(sri);
                    }
                }
            }

            return neighbours;
        }


        /// <summary>
        /// 
        /// </summary>
        /// <param name="regionHandle"></param>
        /// <returns></returns>
        public RegionInfo RequestNeighbourInfo(ulong regionHandle)
        {
            RegionInfo regionInfo = m_localBackend.RequestNeighbourInfo(regionHandle);

            if (regionInfo != null)
            {
                return regionInfo;
            }

            if (m_remoteRegionInfoCache.TryGetValue(regionHandle, out regionInfo))
            {
            }
            else
            {
                Hashtable requestData = new Hashtable();
                requestData["region_handle"] = regionHandle.ToString();
                requestData["authkey"] = this.serversInfo.GridSendKey;
                ArrayList SendParams = new ArrayList();
                SendParams.Add(requestData);
                XmlRpcRequest GridReq = new XmlRpcRequest("simulator_data_request", SendParams);
                XmlRpcResponse GridResp = GridReq.Send(this.serversInfo.GridURL, 3000);

                Hashtable responseData = (Hashtable) GridResp.Value;

                if (responseData.ContainsKey("error"))
                {
                    Console.WriteLine("error received from grid server" + responseData["error"]);
                    return null;
                }

                uint regX = Convert.ToUInt32((string) responseData["region_locx"]);
                uint regY = Convert.ToUInt32((string) responseData["region_locy"]);
                string internalIpStr = (string) responseData["sim_ip"];
                uint port = Convert.ToUInt32(responseData["sim_port"]);
                string externalUri = (string) responseData["sim_uri"];

                IPEndPoint neighbourInternalEndPoint = new IPEndPoint(IPAddress.Parse(internalIpStr), (int) port);
                string neighbourExternalUri = externalUri;
                regionInfo = new RegionInfo(regX, regY, neighbourInternalEndPoint, internalIpStr);

                regionInfo.RemotingPort = Convert.ToUInt32((string) responseData["remoting_port"]);
                regionInfo.RemotingAddress = internalIpStr;

                regionInfo.RegionID = new LLUUID((string) responseData["region_UUID"]);
                regionInfo.RegionName = (string) responseData["region_name"];

                m_remoteRegionInfoCache.Add( regionHandle, regionInfo );
            }

            return regionInfo;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="minX"></param>
        /// <param name="minY"></param>
        /// <param name="maxX"></param>
        /// <param name="maxY"></param>
        /// <returns></returns>
        public List<MapBlockData> RequestNeighbourMapBlocks(int minX, int minY, int maxX, int maxY)
        {
            Hashtable respData = MapBlockQuery(minX, minY, maxX, maxY);

            List<MapBlockData> neighbours = new List<MapBlockData>();

            foreach (ArrayList a in respData.Values)
            {
                foreach (Hashtable n in a)
                {
                    MapBlockData neighbour = new MapBlockData();

                    neighbour.X = Convert.ToUInt16(n["x"]);
                    neighbour.Y = Convert.ToUInt16(n["y"]);

                    neighbour.Name = (string)n["name"];
                    neighbour.Access = Convert.ToByte(n["access"]);
                    neighbour.RegionFlags = Convert.ToUInt32(n["region-flags"]);
                    neighbour.WaterHeight = Convert.ToByte(n["water-height"]);
                    neighbour.MapImageId = new LLUUID((string)n["map-image-id"]);

                    neighbours.Add(neighbour);
                }
            }

            return neighbours;
        }

        /// <summary>
        /// Performs a XML-RPC query against the grid server returning mapblock information in the specified coordinates
        /// </summary>
        /// <remarks>REDUNDANT - OGS1 is to be phased out in favour of OGS2</remarks>
        /// <param name="minX">Minimum X value</param>
        /// <param name="minY">Minimum Y value</param>
        /// <param name="maxX">Maximum X value</param>
        /// <param name="maxY">Maximum Y value</param>
        /// <returns>Hashtable of hashtables containing map data elements</returns>
        private Hashtable MapBlockQuery(int minX, int minY, int maxX, int maxY)
        {
            Hashtable param = new Hashtable();
            param["xmin"] = minX;
            param["ymin"] = minY;
            param["xmax"] = maxX;
            param["ymax"] = maxY;
            IList parameters = new ArrayList();
            parameters.Add(param);
            XmlRpcRequest req = new XmlRpcRequest("map_block", parameters);
            XmlRpcResponse resp = req.Send(serversInfo.GridURL, 10000);
            Hashtable respData = (Hashtable)resp.Value;
            return respData;
        }

        /// <summary>
        /// A ping / version check
        /// </summary>
        /// <param name="request"></param>
        /// <returns></returns>
        public XmlRpcResponse PingCheckReply(XmlRpcRequest request)
        {
            XmlRpcResponse response = new XmlRpcResponse();

            Hashtable respData = new Hashtable();
            respData["online"] = "true";

            m_localBackend.PingCheckReply(respData);

            response.Value = respData;

            return response;
        }


        // Grid Request Processing
        /// <summary>
        /// 
        /// </summary>
        /// <param name="request"></param>
        /// <returns></returns>
        public XmlRpcResponse ExpectUser(XmlRpcRequest request)
        {
            Console.WriteLine("Expecting User...");
            Hashtable requestData = (Hashtable)request.Params[0];
            AgentCircuitData agentData = new AgentCircuitData();
            agentData.SessionID = new LLUUID((string)requestData["session_id"]);
            agentData.SecureSessionID = new LLUUID((string)requestData["secure_session_id"]);
            agentData.firstname = (string)requestData["firstname"];
            agentData.lastname = (string)requestData["lastname"];
            agentData.AgentID = new LLUUID((string)requestData["agent_id"]);
            agentData.circuitcode = Convert.ToUInt32(requestData["circuit_code"]);
            agentData.CapsPath = (string)requestData["caps_path"];

            if (requestData.ContainsKey("child_agent") && requestData["child_agent"].Equals("1"))
            {
                agentData.child = true;
            }
            else
            {
                agentData.startpos = new LLVector3(Convert.ToUInt32(requestData["startpos_x"]), Convert.ToUInt32(requestData["startpos_y"]), Convert.ToUInt32(requestData["startpos_z"]));
                agentData.child = false;

            }

            ulong regionHandle = Convert.ToUInt64((string)requestData["regionhandle"]);

            m_localBackend.TriggerExpectUser(regionHandle, agentData);

            MainLog.Instance.Verbose("ExpectUser() - Welcoming new user...");

            return new XmlRpcResponse();
        }

        #region m_interRegion Comms
        /// <summary>
        /// 
        /// </summary>
        private void StartRemoting()
        {
            TcpChannel ch = new TcpChannel(NetworkServersInfo.RemotingListenerPort);
            ChannelServices.RegisterChannel(ch, false); // Disabled security as Mono doesnt support this.

            WellKnownServiceTypeEntry wellType = new WellKnownServiceTypeEntry(typeof(OGS1InterRegionRemoting), "InterRegions", WellKnownObjectMode.Singleton);
            RemotingConfiguration.RegisterWellKnownServiceType(wellType);
            InterRegionSingleton.Instance.OnArrival += this.TriggerExpectAvatarCrossing;
            InterRegionSingleton.Instance.OnChildAgent += this.IncomingChildAgent;
        }

        #region Methods called by regions in this instance
        /// <summary>
        /// 
        /// </summary>
        /// <param name="regionHandle"></param>
        /// <param name="agentData"></param>
        /// <returns></returns>
        public bool InformRegionOfChildAgent(ulong regionHandle, AgentCircuitData agentData)
        {
            try
            {
                if (m_localBackend.InformRegionOfChildAgent(regionHandle, agentData))
                {
                    return true;
                }

                RegionInfo regInfo = this.RequestNeighbourInfo(regionHandle);
                if (regInfo != null)
                {
                    //don't want to be creating a new link to the remote instance every time like we are here
                    bool retValue = false;


                    OGS1InterRegionRemoting remObject = (OGS1InterRegionRemoting)Activator.GetObject(
                        typeof(OGS1InterRegionRemoting),
                        "tcp://" + regInfo.RemotingAddress + ":" + regInfo.RemotingPort + "/InterRegions");
                    
                    if (remObject != null)
                    {
                        retValue = remObject.InformRegionOfChildAgent(regionHandle, agentData);
                    }
                    else
                    {
                        Console.WriteLine("remoting object not found");
                    }
                    remObject = null;


                    return retValue;
                }

                return false;
            }
            catch (System.Runtime.Remoting.RemotingException e)
            {
                MainLog.Instance.Error("Remoting Error: Unable to connect to remote region.\n" + e.ToString());
                return false;
            }
            catch (SocketException e)
            {
                MainLog.Instance.Error("Socket Error: Unable to connect to remote region.\n" + e.ToString());
                return false;
            }
            catch (InvalidCredentialException e)
            {
                MainLog.Instance.Error("Invalid Credentials: Unable to connect to remote region.\n" + e.ToString());
                return false;
            }
            catch (AuthenticationException e)
            {
                MainLog.Instance.Error("Authentication exception: Unable to connect to remote region.\n" + e.ToString());
                return false;
            }
            catch (Exception e)
            {
                MainLog.Instance.Error("Unknown exception: Unable to connect to remote region.\n" + e.ToString());
                return false;
            }
            return true;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="regionHandle"></param>
        /// <param name="agentID"></param>
        /// <param name="position"></param>
        /// <returns></returns>
        public bool ExpectAvatarCrossing(ulong regionHandle, LLUUID agentID, LLVector3 position, bool isFlying)
        {
            try
            {
                if (m_localBackend.TriggerExpectAvatarCrossing(regionHandle, agentID, position, isFlying))
                {
                    return true;
                }

                RegionInfo regInfo = this.RequestNeighbourInfo(regionHandle);
                if (regInfo != null)
                {
                    bool retValue = false;
                    OGS1InterRegionRemoting remObject = (OGS1InterRegionRemoting)Activator.GetObject(
                        typeof(OGS1InterRegionRemoting),
                        "tcp://" + regInfo.RemotingAddress + ":" + regInfo.RemotingPort + "/InterRegions");
                    if (remObject != null)
                    {
                        retValue = remObject.ExpectAvatarCrossing(regionHandle, agentID, position, isFlying);
                    }
                    else
                    {
                        Console.WriteLine("remoting object not found");
                    }
                    remObject = null;

                    return retValue;
                }
                //TODO need to see if we know about where this region is and use .net remoting 
                // to inform it. 
                return false;
            }
            catch (System.Runtime.Remoting.RemotingException e)
            {
                MainLog.Instance.Error("Remoting Error: Unable to connect to remote region.\n" + e.ToString());
                return false;
            }
            catch
            {
                return false;
            }
        }

        public bool AcknowledgeAgentCrossed(ulong regionHandle, LLUUID agentId)
        {
            return m_localBackend.AcknowledgeAgentCrossed(regionHandle, agentId);
        }

        #endregion

        #region Methods triggered by calls from external instances
        /// <summary>
        /// 
        /// </summary>
        /// <param name="regionHandle"></param>
        /// <param name="agentData"></param>
        /// <returns></returns>
        public bool IncomingChildAgent(ulong regionHandle, AgentCircuitData agentData)
        {
            try
            {
                return m_localBackend.IncomingChildAgent(regionHandle, agentData);
            }
            catch (System.Runtime.Remoting.RemotingException e)
            {
                MainLog.Instance.Error("Remoting Error: Unable to connect to remote region.\n" + e.ToString());
                return false;
            }
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="regionHandle"></param>
        /// <param name="agentID"></param>
        /// <param name="position"></param>
        /// <returns></returns>
        public bool TriggerExpectAvatarCrossing(ulong regionHandle, LLUUID agentID, LLVector3 position, bool isFlying)
        {

            try
            {
                return m_localBackend.TriggerExpectAvatarCrossing(regionHandle, agentID, position, isFlying);
            }
            catch (System.Runtime.Remoting.RemotingException e)
            {
                MainLog.Instance.Error("Remoting Error: Unable to connect to remote region.\n" + e.ToString());
                return false;
            }
        }
        #endregion
        #endregion
    }
}