Implement a general way to store selection data for gossip and fix trainer exploit

Game/Entities/Creature/Gossip.cs

@@ -182,8 +182,6 @@ namespace Game.Misc
 
         public void SetMenuId(uint menu_id) { _menuId = menu_id; }
         public uint GetMenuId() { return _menuId; }
-        public void SetSenderGUID(ObjectGuid guid) { _senderGUID = guid; }
-        public ObjectGuid GetSenderGUID() { return _senderGUID; }
         public void SetLocale(LocaleConstant locale) { _locale = locale; }
         LocaleConstant GetLocale() { return _locale; }
 
@@ -215,10 +213,21 @@ namespace Game.Misc
         Dictionary<uint, GossipMenuItem> _menuItems = new Dictionary<uint, GossipMenuItem>();
         Dictionary<uint, GossipMenuItemData> _menuItemData = new Dictionary<uint, GossipMenuItemData>();
         uint _menuId;
-        ObjectGuid _senderGUID;
         LocaleConstant _locale;
     }
 
+    public class InteractionData
+    {
+        public void Reset()
+        {
+            SourceGuid.Clear();
+            TrainerId = 0;
+        }
+
+        public ObjectGuid SourceGuid;
+        public uint TrainerId;
+    }
+
     public class PlayerMenu
     {
         public PlayerMenu(WorldSession session)
@@ -236,7 +245,8 @@ namespace Game.Misc
 
         public void SendGossipMenu(uint titleTextId, ObjectGuid objectGUID)
         {
-            _gossipMenu.SetSenderGUID(objectGUID);
+            _interactionData.Reset();
+            _interactionData.SourceGuid = objectGUID;
 
             GossipMessagePkt packet = new GossipMessagePkt();
             packet.GossipGUID = objectGUID;
@@ -294,7 +304,7 @@ namespace Game.Misc
 
         public void SendCloseGossip()
         {
-            _gossipMenu.SetSenderGUID(ObjectGuid.Empty);
+            _interactionData.Reset();
 
             _session.SendPacket(new GossipComplete());
         }
@@ -726,6 +736,7 @@ namespace Game.Misc
 
         public GossipMenu GetGossipMenu() { return _gossipMenu; }
         public QuestMenu GetQuestMenu() { return _questMenu; }
+        public InteractionData GetInteractionData() { return _interactionData; }
 
         bool IsEmpty() { return _gossipMenu.IsEmpty() && _questMenu.IsEmpty(); }
 
@@ -736,6 +747,7 @@ namespace Game.Misc
         GossipMenu _gossipMenu = new GossipMenu();
         QuestMenu _questMenu = new QuestMenu();
         WorldSession _session;
+        InteractionData _interactionData = new InteractionData();
     }
 
     public class QuestMenu

Game/Entities/Player/Player.Fields.cs

@@ -140,8 +140,6 @@ namespace Game.Entities
 
         RestMgr _restMgr;
 
-        uint _currentTrainerId;
-
         //Combat 
         int[] baseRatingValue = new int[(int)CombatRating.Max];
         public float[][] m_auraBaseMod = new float[(int)BaseModGroup.End][];

Game/Entities/Player/Player.cs

@@ -1034,9 +1034,6 @@ namespace Game.Entities
 
         public RestMgr GetRestMgr() { return _restMgr; }
 
-        public uint GetCurrentTrainerId() { return _currentTrainerId; }
-        public void SetCurrentTrainerId(uint trainerId) { _currentTrainerId = trainerId; }
-
         public bool IsAdvancedCombatLoggingEnabled()  { return _advancedCombatLoggingEnabled; }
         public void SetAdvancedCombatLogging(bool enabled) { _advancedCombatLoggingEnabled = enabled; }
 

Game/Handlers/MailHandler.cs

@@ -367,6 +367,9 @@ namespace Game
         [WorldPacketHandler(ClientOpcodes.MailReturnToSender)]
         void HandleMailReturnToSender(MailReturnToSender packet)
         {
+            if (!CanOpenMailBox(_player.PlayerTalkClass.GetInteractionData().SourceGuid))
+                return;
+
             Player player = GetPlayer();
             Mail m = player.GetMail(packet.MailID);
             if (m == null || m.state == MailState.Deleted || m.deliver_time > Time.UnixTime || m.sender != packet.SenderGUID.GetCounter())
@@ -576,6 +579,8 @@ namespace Game
                     response.Mails.Add(new MailListEntry(m, player));
             }
 
+            player.PlayerTalkClass.GetInteractionData().Reset();
+            player.PlayerTalkClass.GetInteractionData().SourceGuid = packet.Mailbox;
             SendPacket(response);
 
             // recalculate m_nextMailDelivereTime and unReadMails

Game/Handlers/MiscHandler.cs

@@ -432,6 +432,12 @@ namespace Game
                 _player.Prestige();
         }
 
+        [WorldPacketHandler(ClientOpcodes.CloseInteraction, Processing = PacketProcessing.ThreadSafe)]
+        void HandleCloseInteraction(CloseInteraction packet)
+        {
+            _player.PlayerTalkClass.GetInteractionData().Reset();
+        }
+
         [WorldPacketHandler(ClientOpcodes.ChatUnregisterAllAddonPrefixes)]
         void HandleUnregisterAllAddonPrefixes(ChatUnregisterAllAddonPrefixes packet)
         {

Game/Handlers/NPCHandler.cs

@@ -79,7 +79,9 @@ namespace Game
                 return;
             }
 
-            _player.SetCurrentTrainerId(trainerId);
+            _player.PlayerTalkClass.GetInteractionData().Reset();
+            _player.PlayerTalkClass.GetInteractionData().SourceGuid = guid;
+            _player.PlayerTalkClass.GetInteractionData().TrainerId = trainerId;
             trainer.SendSpells(unit, _player, GetSessionDbLocaleIndex());
         }
 
@@ -97,7 +99,10 @@ namespace Game
             if (_player.HasUnitState(UnitState.Died))
                 _player.RemoveAurasByType(AuraType.FeignDeath);
 
-            if (_player.GetCurrentTrainerId() != packet.TrainerID)
+            if (_player.PlayerTalkClass.GetInteractionData().SourceGuid != packet.TrainerGUID)
+                return;
+
+            if (_player.PlayerTalkClass.GetInteractionData().TrainerId != packet.TrainerID)
                 return;
 
             // check present spell in trainer spell list
@@ -164,7 +169,7 @@ namespace Game
                 return;
 
             // Prevent cheating on C# scripted menus
-            if (GetPlayer().PlayerTalkClass.GetGossipMenu().GetSenderGUID() != packet.GossipUnit)
+            if (GetPlayer().PlayerTalkClass.GetInteractionData().SourceGuid != packet.GossipUnit)
                 return;
 
             Creature unit = null;

Game/Network/Packets/MiscPackets.cs

@@ -1287,4 +1287,16 @@ namespace Game.Network.Packets
 
         public override void Read() { }
     }
+
+    class CloseInteraction : ClientPacket
+    {
+        public CloseInteraction(WorldPacket packet) : base(packet) { }
+
+        public override void Read()
+        {
+            SourceGuid = _worldPacket.ReadPackedGuid();
+        }
+
+        public ObjectGuid SourceGuid;
+    }
 }