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using Nini.Config;
using System;
using System.Collections;
using System.Collections.Generic;
using OpenSim.Framework;
using OpenSim.Framework.Console;
using OpenSim.Region.Environment.Interfaces;
using OpenSim.Region.Environment.Scenes;
using libsecondlife;
using Nwc.XmlRpc;

namespace OpenSim.Region.Environment.Modules
{
    public class FriendsModule : IRegionModule
    {
        private static readonly log4net.ILog m_log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

        private List<Scene> m_scene = new List<Scene>();

        Dictionary<LLUUID, LLUUID> m_pendingFriendRequests = new Dictionary<LLUUID, LLUUID>();

        public void Initialise(Scene scene, IConfigSource config)
        {
            lock (m_scene)
            {
                if (m_scene.Count == 0)
                {
                    scene.AddXmlRPCHandler("presence_update", processPresenceUpdate);
                }

                if (!m_scene.Contains(scene))
                    m_scene.Add(scene);
            }
            scene.EventManager.OnNewClient += OnNewClient;
            scene.EventManager.OnGridInstantMessageToFriendsModule += OnGridInstantMessage;
            
        }
        public XmlRpcResponse processPresenceUpdate(XmlRpcRequest req)
        {
            m_log.Info("[FRIENDS]: Got Notification about a user! OMG");
            return new XmlRpcResponse();
        }
        private void OnNewClient(IClientAPI client)
        {
            // All friends establishment protocol goes over instant message
            // There's no way to send a message from the sim 
            // to a user to 'add a friend' without causing dialog box spam
            // 
            // The base set of friends are added when the user signs on in their XMLRPC response
            // Generated by LoginService.  The friends are retreived from the database by the UserManager

            // Subscribe to instant messages
            client.OnInstantMessage += OnInstantMessage;
            client.OnApproveFriendRequest += OnApprovedFriendRequest;
            client.OnDenyFriendRequest += OnDenyFriendRequest;
            client.OnTerminateFriendship += OnTerminateFriendship;

            
        }

        private void OnInstantMessage(IClientAPI client,LLUUID fromAgentID,
                                      LLUUID fromAgentSession, LLUUID toAgentID,
                                      LLUUID imSessionID, uint timestamp, string fromAgentName,
                                      string message, byte dialog, bool fromGroup, byte offline, 
                                      uint ParentEstateID, LLVector3 Position, LLUUID RegionID, 
                                      byte[] binaryBucket)
        {
            // Friend Requests go by Instant Message..    using the dialog param
            // https://wiki.secondlife.com/wiki/ImprovedInstantMessage

            // 38 == Offer friendship
            if (dialog == (byte)38)
            {
                LLUUID friendTransactionID = LLUUID.Random();

                m_pendingFriendRequests.Add(friendTransactionID, fromAgentID);

                m_log.Info("[FRIEND]: 38 - From:" + fromAgentID.ToString() + " To: " + toAgentID.ToString() + " Session:" + imSessionID.ToString() + " Message:" + message);
                GridInstantMessage msg = new GridInstantMessage();
                msg.fromAgentID = fromAgentID.UUID;
                msg.fromAgentSession = fromAgentSession.UUID;
                msg.toAgentID = toAgentID.UUID;
                msg.imSessionID = friendTransactionID.UUID; // This is the item we're mucking with here
                m_log.Info("[FRIEND]: Filling Session: " + msg.imSessionID.ToString());
                msg.timestamp = timestamp;
                if (client != null)
                {
                    msg.fromAgentName = client.FirstName + " " + client.LastName;// fromAgentName;
                }
                else
                {
                    msg.fromAgentName = "(hippos)";// Added for posterity.  This means that we can't figure out who sent it
                }
                msg.message = message;
                msg.dialog = dialog;
                msg.fromGroup = fromGroup;
                msg.offline = offline;
                msg.ParentEstateID = ParentEstateID;
                msg.Position = new sLLVector3(Position);
                msg.RegionID = RegionID.UUID;
                msg.binaryBucket = binaryBucket;
                // We don't really care which scene we pipe it through.
                m_scene[0].TriggerGridInstantMessage(msg, InstantMessageReceiver.IMModule);
            }

            // 39 == Accept Friendship
            if (dialog == (byte)39)
            {
                m_log.Info("[FRIEND]: 39 - From:" + fromAgentID.ToString() + " To: " + toAgentID.ToString() + " Session:" + imSessionID.ToString() + " Message:" + message);
            }

            // 40 == Decline Friendship
            if (dialog == (byte)40)
            {
                m_log.Info("[FRIEND]: 40 - From:" + fromAgentID.ToString() + " To: " + toAgentID.ToString() + " Session:" + imSessionID.ToString() + " Message:" + message);
            }
        }

        private void OnApprovedFriendRequest(IClientAPI client, LLUUID agentID, LLUUID transactionID, List<LLUUID> callingCardFolders)
        {
            if (m_pendingFriendRequests.ContainsKey(transactionID))
            {
                // Found Pending Friend Request with that Transaction..    
                Scene SceneAgentIn = m_scene[0];

                // Found Pending Friend Request with that Transaction..    
                ScenePresence agentpresence = GetPresenceFromAgentID(agentID);
                if (agentpresence != null)
                {
                    SceneAgentIn = agentpresence.Scene;
                }

                // Compose response to other agent.
                GridInstantMessage msg = new GridInstantMessage();
                msg.toAgentID = m_pendingFriendRequests[transactionID].UUID;
                msg.fromAgentID = agentID.UUID;
                msg.fromAgentName = client.FirstName + " " + client.LastName;
                msg.fromAgentSession = client.SessionId.UUID;
                msg.fromGroup = false;
                msg.imSessionID = transactionID.UUID;
                msg.message = agentID.UUID.ToString();
                msg.ParentEstateID = 0;
                msg.timestamp = (uint)Util.UnixTimeSinceEpoch();
                msg.RegionID = SceneAgentIn.RegionInfo.RegionID.UUID;
                msg.dialog = (byte)39;// Approved friend request
                msg.Position = new sLLVector3();
                msg.offline = (byte)0;
                msg.binaryBucket = new byte[0];
                // We don't really care which scene we pipe it through, it goes to the shared IM Module and/or the database

                SceneAgentIn.TriggerGridInstantMessage(msg, InstantMessageReceiver.IMModule);
                SceneAgentIn.StoreAddFriendship(m_pendingFriendRequests[transactionID], agentID, (uint)1);
                m_pendingFriendRequests.Remove(transactionID);

                // TODO: Inform agent that the friend is online
            }
        }

        private void OnDenyFriendRequest(IClientAPI client, LLUUID agentID, LLUUID transactionID, List<LLUUID> callingCardFolders)
        {
            if (m_pendingFriendRequests.ContainsKey(transactionID))
            {
                Scene SceneAgentIn = m_scene[0];

                // Found Pending Friend Request with that Transaction..    
                ScenePresence agentpresence = GetPresenceFromAgentID(agentID);
                if (agentpresence != null)
                {
                    SceneAgentIn = agentpresence.Scene;
                }
                // Compose response to other agent.
                GridInstantMessage msg = new GridInstantMessage();
                msg.toAgentID = m_pendingFriendRequests[transactionID].UUID;
                msg.fromAgentID = agentID.UUID;
                msg.fromAgentName = client.FirstName + " " + client.LastName;
                msg.fromAgentSession = client.SessionId.UUID;
                msg.fromGroup = false;
                msg.imSessionID = transactionID.UUID;
                msg.message = agentID.UUID.ToString();
                msg.ParentEstateID = 0;
                msg.timestamp = (uint)Util.UnixTimeSinceEpoch();
                msg.RegionID = SceneAgentIn.RegionInfo.RegionID.UUID;
                msg.dialog = (byte)40;// Deny friend request
                msg.Position = new sLLVector3();
                msg.offline = (byte)0;
                msg.binaryBucket = new byte[0];
                SceneAgentIn.TriggerGridInstantMessage(msg, InstantMessageReceiver.IMModule);
                m_pendingFriendRequests.Remove(transactionID);
            }
        }

        private void OnTerminateFriendship(IClientAPI client, LLUUID agent, LLUUID exfriendID)
        {
            m_scene[0].StoreRemoveFriendship(agent, exfriendID);
            // TODO: Inform the client that the ExFriend is offline
        }

        private void OnGridInstantMessage(GridInstantMessage msg)
        {
            // Trigger the above event handler
            OnInstantMessage(null,new LLUUID(msg.fromAgentID), new LLUUID(msg.fromAgentSession),
                new LLUUID(msg.toAgentID), new LLUUID(msg.imSessionID), msg.timestamp, msg.fromAgentName,
                msg.message, msg.dialog, msg.fromGroup, msg.offline, msg.ParentEstateID,
                new LLVector3(msg.Position.x, msg.Position.y, msg.Position.z), new LLUUID(msg.RegionID),
                msg.binaryBucket);
        }

        private ScenePresence GetPresenceFromAgentID(LLUUID AgentID)
        {
            ScenePresence returnAgent = null;
            lock (m_scene)
            {
                ScenePresence queryagent = null;
                for (int i = 0; i < m_scene.Count; i++)
                {
                    queryagent = m_scene[i].GetScenePresence(AgentID);
                    if (queryagent != null)
                    {
                        if (!queryagent.IsChildAgent)
                        {
                            returnAgent = queryagent;
                            break;
                        }
                    }
                }
            }
            return returnAgent;

        }

        public void PostInitialise()
        {
        }

        public void Close()
        {
        }

        public string Name
        {
            get { return "FriendsModule"; }
        }

        public bool IsSharedModule
        {
            get { return true; }
        }
    }
}