Core/Groups: Fixes groups staying linked with players.

Source/Framework/Collections/LinkedListElement.cs

@@ -1,12 +1,28 @@
 // Copyright (c) CypherCore <http://github.com/CypherCore> All rights reserved.
 // Licensed under the GNU GENERAL PUBLIC LICENSE. See LICENSE file in the project root for full license information.
 
+using System.Collections.Generic;
+
 namespace Framework.Collections
 {
     public class LinkedListElement
     {
-        internal LinkedListElement INext;
+        internal LinkedListElement INext
-        internal LinkedListElement IPrev;
+        {
+            get;
+            set
+            {
+                field = value;
+            }
+        }
+        internal LinkedListElement IPrev
+        {
+            get;
+            set
+            {
+                field = value;
+            }
+        }
 
         public LinkedListElement()
         {
@@ -52,32 +68,31 @@ namespace Framework.Collections
 
     public class LinkedListHead
     {
-        LinkedListElement _iFirst = new();
+        LinkedListElement iHeader = new();
-        LinkedListElement _iLast = new();
         uint _iSize;
 
         public LinkedListHead()
         {
             _iSize = 0;
-            // create empty list
             
-            _iFirst.INext = _iLast;
+            // create empty list
-            _iLast.IPrev = _iFirst;
+            iHeader.INext = new();
+            iHeader.IPrev = new();
         }
 
-        public bool IsEmpty() { return (!_iFirst.INext.IsInList()); }
+        public bool IsEmpty() { return iHeader.INext == iHeader; }
 
-        public LinkedListElement GetFirstElement() { return (IsEmpty() ? null : _iFirst.INext); }
+        public LinkedListElement GetFirstElement() { return (IsEmpty() ? null : iHeader.INext); }
-        public LinkedListElement GetLastElement() { return (IsEmpty() ? null : _iLast.IPrev); }
+        public LinkedListElement GetLastElement() { return (IsEmpty() ? null : iHeader); }
 
         public void InsertFirst(LinkedListElement pElem)
         {
-            _iFirst.InsertAfter(pElem);
+            iHeader.InsertBefore(pElem);
         }
 
         public void InsertLast(LinkedListElement pElem)
         {
-            _iLast.InsertBefore(pElem);
+            iHeader.InsertBefore(pElem);
         }
 
         public uint GetSize()

Source/Framework/Dynamic/Reference.cs

@@ -1,11 +1,14 @@
 // Copyright (c) CypherCore <http://github.com/CypherCore> All rights reserved.
 // Licensed under the GNU GENERAL PUBLIC LICENSE. See LICENSE file in the project root for full license information.
 
-using Framework.Collections;
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
 
 namespace Framework.Dynamic
 {
-    public class Reference<TO, FROM> : LinkedListElement where TO : class where FROM : class
+    public class Reference<TO, FROM> where TO : class where FROM : class
     {
         TO _RefTo;
         FROM _RefFrom;
@@ -21,7 +24,8 @@ namespace Framework.Dynamic
 
         public Reference()
         {
-            _RefTo = null; _RefFrom = null;
+            _RefTo = null;
+            _RefFrom = null;
         }
 
         // Create new link
@@ -43,7 +47,6 @@ namespace Framework.Dynamic
         public void Unlink()
         {
             TargetObjectDestroyLink();
-            Delink();
             _RefTo = null;
             _RefFrom = null;
         }
@@ -53,7 +56,6 @@ namespace Framework.Dynamic
         public void Invalidate()                                   // the iRefFrom MUST remain!!
         {
             SourceObjectDestroyLink();
-            Delink();
             _RefTo = null;
         }
 
@@ -62,26 +64,60 @@ namespace Framework.Dynamic
             return _RefTo != null;
         }
 
-        public Reference<TO, FROM> Next() { return ((Reference<TO, FROM>)GetNextElement()); }
-        public Reference<TO, FROM> Prev() { return ((Reference<TO, FROM>)GetPrevElement()); }
-
         public TO GetTarget() { return _RefTo; }
 
         public FROM GetSource() { return _RefFrom; }
     }
 
-    public class RefManager<TO, FROM> : LinkedListHead where TO : class where FROM : class
+    public class RefManager<ReferenceType> : IEnumerable where ReferenceType : class, new()
     {
+        LinkedList<ReferenceType> linkedList = new LinkedList<ReferenceType>();
+
         ~RefManager() { ClearReferences(); }
 
-        public Reference<TO, FROM> GetFirst() { return (Reference<TO, FROM>)base.GetFirstElement(); }
+        public void InsertFirst(ReferenceType pElem)
-        public Reference<TO, FROM> GetLast() { return (Reference<TO, FROM>)base.GetLastElement(); }
+        {
+            linkedList.AddFirst(pElem);
+        }
+
+        public void InsertLast(ReferenceType pElem)
+        {
+            linkedList.AddLast(pElem);
+        }
+
+        public ReferenceType Find(Func<ReferenceType, bool> func)
+        {
+            return linkedList.FirstOrDefault(func);
+        }
+
+        public void Remove(Func<ReferenceType, bool> func)
+        {
+            linkedList.Remove(Find(func));
+        }
+
+        public int GetSize()
+        {
+            return linkedList.Count;
+        }
+
+        public ReferenceType GetFirst() { return linkedList.First?.Value; }
+        public ReferenceType GetLast() { return linkedList.Last?.Value; }
+
+        public IEnumerator<ReferenceType> GetEnumerator()
+        {
+            return linkedList.GetEnumerator();
+        }
+
+        IEnumerator IEnumerable.GetEnumerator()
+        {
+            return GetEnumerator();
+        }
 
         public void ClearReferences()
         {
-            Reference<TO, FROM> refe;
+            ReferenceType refe;
             while ((refe = GetFirst()) != null)
-                refe.Invalidate();
+                linkedList.Remove(refe);
         }
     }
 }

Source/Game/AI/CoreAI/PetAI.cs

@@ -592,10 +592,10 @@ namespace Game.AI
             _allySet.Add(me.GetGUID());
             if (group != null) // add group
             {
-                for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
                 {
-                    Player target = refe.GetSource();
+                    Player target = groupRef.GetSource();
-                    if (target == null || !target.IsInMap(owner) || !group.SameSubGroup(owner.ToPlayer(), target))
+                    if (!target.IsInMap(owner) || !group.SameSubGroup(owner.ToPlayer(), target))
                         continue;
 
                     if (target.GetGUID() == owner.GetGUID())

Source/Game/AI/ScriptedAI/ScriptedEscortAI.cs

@@ -83,10 +83,9 @@ namespace Game.AI
                 Group group = player.GetGroup();
                 if (group != null)
                 {
-                    for (GroupReference groupRef = group.GetFirstMember(); groupRef != null; groupRef = groupRef.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
                         Player member = groupRef.GetSource();
-                        if (member != null)
                         if (member.IsInMap(player))
                             member.FailQuest(_escortQuest.Id);
                     }
@@ -150,10 +149,9 @@ namespace Game.AI
                 Group group = player.GetGroup();
                 if (group != null)
                 {
-                    for (GroupReference groupRef = group.GetFirstMember(); groupRef != null; groupRef = groupRef.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
                         Player member = groupRef.GetSource();
-                        if (member != null)
                         if (me.IsWithinDistInMap(member, GetMaxPlayerDistance()))
                             return true;
                     }

Source/Game/AI/ScriptedAI/ScriptedFollowerAI.cs

@@ -52,10 +52,9 @@ namespace Game.AI
                 Group group = player.GetGroup();
                 if (group != null)
                 {
-                    for (GroupReference groupRef = group.GetFirstMember(); groupRef != null; groupRef = groupRef.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
                         Player member = groupRef.GetSource();
-                        if (member != null)
                         if (member.IsInMap(player))
                             member.FailQuest(_questForFollow);
                     }
@@ -109,12 +108,9 @@ namespace Game.AI
                         Group group = player.GetGroup();
                         if (group != null)
                         {
-                            for (GroupReference groupRef = group.GetFirstMember(); groupRef != null && (maxRangeExceeded || questAbandoned); groupRef = groupRef.Next())
+                            foreach (GroupReference groupRef in group.GetMembers())
                             {
                                 Player member = groupRef.GetSource();
-                                if (member == null)
-                                    continue;
-
                                 if (maxRangeExceeded && me.IsWithinDistInMap(member, 100.0f))
                                     maxRangeExceeded = false;
 
@@ -253,10 +249,10 @@ namespace Game.AI
                     Group group = player.GetGroup();
                     if (group != null)
                     {
-                        for (GroupReference groupRef = group.GetFirstMember(); groupRef != null; groupRef = groupRef.Next())
+                        foreach (GroupReference groupRef in group.GetMembers())
                         {
                             Player member = groupRef.GetSource();
-                            if (member != null && me.IsWithinDistInMap(member, 100.0f) && member.IsAlive())
+                            if (me.IsWithinDistInMap(member, 100.0f) && member.IsAlive())
                             {
                                 Log.outDebug(LogFilter.Scripts, $"FollowerAI::GetLeaderForFollower: GetLeader changed and returned new leader. ({me.GetGUID()})");
                                 _leaderGUID = member.GetGUID();

Source/Game/AI/SmartScripts/SmartAI.cs

@@ -227,7 +227,7 @@ namespace Game.AI
                     Group group = player.GetGroup();
                     if (group != null)
                     {
-                        for (GroupReference groupRef = group.GetFirstMember(); groupRef != null; groupRef = groupRef.Next())
+                        foreach (GroupReference groupRef in group.GetMembers())
                         {
                             Player groupGuy = groupRef.GetSource();
                             if (!groupGuy.IsInMap(player))
@@ -333,7 +333,7 @@ namespace Game.AI
                     Group group = player.GetGroup();
                     if (group != null)
                     {
-                        for (GroupReference groupRef = group.GetFirstMember(); groupRef != null; groupRef = groupRef.Next())
+                        foreach (GroupReference groupRef in group.GetMembers())
                         {
                             Player groupGuy = groupRef.GetSource();
                             if (groupGuy.IsInMap(player) && me.GetDistance(groupGuy) <= checkDist)

Source/Game/AI/SmartScripts/SmartScript.cs

@@ -2889,10 +2889,9 @@ namespace Game.AI
                             Group group = player.GetGroup();
                             if (group != null)
                             {
-                                for (GroupReference groupRef = group.GetFirstMember(); groupRef != null; groupRef = groupRef.Next())
+                                foreach (GroupReference groupRef in group.GetMembers())
                                 {
                                     Player member = groupRef.GetSource();
-                                    if (member != null)
                                     if (member.IsInMap(player))
                                         targets.Add(member);
                                 }

Source/Game/Achievements/AchievementManager.cs

@@ -985,10 +985,9 @@ namespace Game.Achievements
                 Group group = referencePlayer.GetGroup();
                 if (group != null)
                 {
-                    for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
-                        Player groupMember = refe.GetSource();
+                        Player groupMember = groupRef.GetSource();
-                        if (groupMember != null)
                         if (groupMember.GetGuildId() == _owner.GetId())
                             ca.CompletingPlayers.Add(groupMember.GetGUID());
                     }

Source/Game/Achievements/CriteriaHandler.cs

@@ -9,6 +9,7 @@ using Game.BattleGrounds;
 using Game.DataStorage;
 using Game.Entities;
 using Game.Garrisons;
+using Game.Groups;
 using Game.Maps;
 using Game.Miscellaneous;
 using Game.Networking;
@@ -1725,8 +1726,8 @@ namespace Game.Achievements
                     var group = referencePlayer.GetGroup();
                     if (group != null)
                     {
-                        for (var itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+                        foreach (GroupReference groupRefe in group.GetMembers())
-                            if (itr.GetSource().GetGuildId() == referencePlayer.GetGuildId())
+                            if (groupRefe.GetSource().GetGuildId() == referencePlayer.GetGuildId())
                                 ++guildMemberCount;
                     }
 
@@ -2739,8 +2740,8 @@ namespace Game.Achievements
                     var group = referencePlayer.GetGroup();
                     if (group != null)
                     {
-                        for (var itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+                        foreach (GroupReference groupRef in group.GetMembers())
-                            if (itr.GetSource() != referencePlayer && referencePlayer.m_playerData.VirtualPlayerRealm == itr.GetSource().m_playerData.VirtualPlayerRealm)
+                            if (groupRef.GetSource() != referencePlayer && referencePlayer.m_playerData.VirtualPlayerRealm == groupRef.GetSource().m_playerData.VirtualPlayerRealm)
                                 ++memberCount;
                     }
 
@@ -2845,8 +2846,8 @@ namespace Game.Achievements
                     if (group != null)
                     {
                         uint membersWithAchievement = 0;
-                        for (var itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+                        foreach (GroupReference groupRef in group.GetMembers())
-                            if (itr.GetSource().HasAchieved((uint)secondaryAsset))
+                            if (groupRef.GetSource().HasAchieved((uint)secondaryAsset))
                                 ++membersWithAchievement;
 
                         if (membersWithAchievement > reqValue)
@@ -3283,8 +3284,8 @@ namespace Game.Achievements
                     if (group == null)
                         return false;
 
-                    for (var itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
-                        if (itr.GetSource().GetSession().GetRecruiterId() == referencePlayer.GetSession().GetAccountId())
+                        if (groupRef.GetSource().GetSession().GetRecruiterId() == referencePlayer.GetSession().GetAccountId())
                             return true;
 
                     return false;
@@ -3295,8 +3296,8 @@ namespace Game.Achievements
                     if (group == null)
                         return false;
 
-                    for (var itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
-                        if (itr.GetSource().GetSession().GetAccountId() == referencePlayer.GetSession().GetRecruiterId())
+                        if (groupRef.GetSource().GetSession().GetAccountId() == referencePlayer.GetSession().GetRecruiterId())
                             return true;
 
                     return false;
@@ -3430,8 +3431,8 @@ namespace Game.Achievements
                     var group = referencePlayer.GetGroup();
                     if (group != null)
                     {
-                        for (var itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+                        foreach (GroupReference groupRef in group.GetMembers())
-                            if (!itr.GetSource().HasAchieved(reqValue))
+                            if (!groupRef.GetSource().HasAchieved(reqValue))
                                 return false;
                     }
                     else if (!referencePlayer.HasAchieved(reqValue))

Source/Game/BattleGrounds/BattleGroundQueue.cs

@@ -82,12 +82,9 @@ namespace Game.BattleGrounds
             //add players from group to ginfo
             if (group != null)
             {
-                for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
                 {
-                    Player member = refe.GetSource();
+                    Player member = groupRef.GetSource();
-                    if (member == null)
-                        continue;   // this should never happen
-
                     PlayerQueueInfo pl_info = new();
                     pl_info.LastOnlineTime = lastOnlineTime;
                     pl_info.GroupInfo = ginfo;

Source/Game/Chat/Commands/GroupCommands.cs

@@ -106,11 +106,9 @@ namespace Game.Chat
             if (groupTarget == null)
                 return false;
 
-            for (GroupReference it = groupTarget.GetFirstMember(); it != null; it = it.Next())
+            foreach (GroupReference groupRef in groupTarget.GetMembers())
-            {
-                target = it.GetSource();
-                if (target != null)
             {
+                target = groupRef.GetSource();
                 uint oldlevel = target.GetLevel();
 
                 if (level != oldlevel)
@@ -128,7 +126,6 @@ namespace Game.Chat
                         target.SendSysMessage(CypherStrings.YoursLevelDown, handler.GetNameLink(), level);
                 }
             }
-            }
             return true;
         }
 
@@ -248,12 +245,8 @@ namespace Game.Chat
             if (groupTarget == null)
                 return false;
 
-            for (GroupReference it = groupTarget.GetFirstMember(); it != null; it = it.Next())
+            foreach (GroupReference groupRef in groupTarget.GetMembers())
-            {
+                groupRef.GetSource().DurabilityRepairAll(false, 0, false);
-                Player target = it.GetSource();
-                if (target != null)
-                    target.DurabilityRepairAll(false, 0, false);
-            }
 
             return true;
         }
@@ -270,16 +263,13 @@ namespace Game.Chat
             if (groupTarget == null)
                 return false;
 
-            for (GroupReference it = groupTarget.GetFirstMember(); it != null; it = it.Next())
+            foreach (GroupReference groupRef in groupTarget.GetMembers())
-            {
-                Player target = it.GetSource();
-                if (target != null)
             {
+                Player target = groupRef.GetSource();
                 target.ResurrectPlayer(target.GetSession().HasPermission(RBACPermissions.ResurrectWithFullHps) ? 1.0f : 0.5f);
                 target.SpawnCorpseBones();
                 target.SaveToDB();
             }
-            }
 
             return true;
         }
@@ -326,11 +316,10 @@ namespace Game.Chat
                 }
             }
 
-            for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
             {
-                Player player = refe.GetSource();
+                Player player = groupRef.GetSource();
-
+                if (player == gmPlayer || player.GetSession() == null)
-                if (player == null || player == gmPlayer || player.GetSession() == null)
                     continue;
 
                 // check online security

Source/Game/Chat/Commands/TeleCommands.cs

@@ -127,18 +127,16 @@ namespace Game.Chat
 
             string nameLink = handler.GetNameLink(target);
 
-            Group grp = target.GetGroup();
+            Group group = target.GetGroup();
-            if (grp == null)
+            if (group == null)
             {
                 handler.SendSysMessage(CypherStrings.NotInGroup, nameLink);
                 return false;
             }
 
-            for (GroupReference refe = grp.GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
             {
-                Player player = refe.GetSource();
+                Player player = groupRef.GetSource();
-                if (player == null || player.GetSession() == null)
-                    continue;
 
                 // check online security
                 if (handler.HasLowerSecurity(player, ObjectGuid.Empty))

Source/Game/DungeonFinding/LFGManager.cs

@@ -397,11 +397,9 @@ namespace Game.DungeonFinding
                 else
                 {
                     byte memberCount = 0;
-                    for (GroupReference refe = grp.GetFirstMember(); refe != null && joinData.result == LfgJoinResult.Ok; refe = refe.Next())
+                    foreach (GroupReference groupRef in grp.GetMembers())
-                    {
-                        Player groupPlayer = refe.GetSource();
-                        if (groupPlayer != null)
                     {
+                        Player groupPlayer = groupRef.GetSource();
                         if (!groupPlayer.GetSession().HasPermission(RBACPermissions.JoinDungeonFinder))
                             joinData.result = LfgJoinResult.NoLfgObject;
                         if (groupPlayer.HasAura(SharedConst.LFGSpellDungeonDeserter))
@@ -417,7 +415,9 @@ namespace Game.DungeonFinding
                         }
                         ++memberCount;
                         players.Add(groupPlayer.GetGUID());
-                        }
+
+                        if (joinData.result != LfgJoinResult.Ok)
+                            break;
                     }
 
                     if (joinData.result == LfgJoinResult.Ok && memberCount != grp.GetMembersCount())
@@ -521,11 +521,9 @@ namespace Game.DungeonFinding
                 SetState(gguid, LfgState.Rolecheck);
                 // Send update to player
                 LfgUpdateData updateData = new(LfgUpdateType.JoinQueue, dungeons);
-                for (GroupReference refe = grp.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in grp.GetMembers())
-                {
-                    Player plrg = refe.GetSource();
-                    if (plrg != null)
                 {
+                    Player plrg = groupRef.GetSource();
                     ObjectGuid pguid = plrg.GetGUID();
                     plrg.GetSession().SendLfgUpdateStatus(updateData, true);
                     SetState(pguid, LfgState.Rolecheck);
@@ -537,7 +535,6 @@ namespace Game.DungeonFinding
                         debugNames += ", ";
                     debugNames += plrg.GetName();
                 }
-                }
                 // Update leader role
                 UpdateRoleCheck(gguid, guid, roles);
             }
@@ -1303,10 +1300,10 @@ namespace Game.DungeonFinding
                 if (!fromOpcode)
                 {
                     // Select a player inside to be teleported to
-                    for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
-                        Player plrg = refe.GetSource();
+                        Player plrg = groupRef.GetSource();
-                        if (plrg != null && plrg != player && plrg.GetMapId() == dungeon.map)
+                        if (plrg != player && plrg.GetMapId() == dungeon.map)
                         {
                             mapid = plrg.GetMapId();
                             x = plrg.GetPositionX();

Source/Game/Entities/Creature/Creature.cs

@@ -1178,10 +1178,10 @@ namespace Game.Entities
 
             foreach (Group partyToForceIntoCombat in partiesToForceIntoCombat)
             {
-                for (GroupReference refe = partyToForceIntoCombat.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in partyToForceIntoCombat.GetMembers())
                 {
-                    Player player = refe.GetSource();
+                    Player player = groupRef.GetSource();
-                    if (player == null || !player.IsInWorld || player.GetMap() != GetMap() || player.IsGameMaster())
+                    if (!player.IsInWorld || player.GetMap() != GetMap() || player.IsGameMaster())
                         continue;
 
                     EngageWithTarget(player);
@@ -1334,9 +1334,9 @@ namespace Game.Entities
             {
                 Group group = player.GetGroup();
                 if (group != null)
-                    for (var itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
-                        if (GetMap().IsRaid() || group.SameSubGroup(player, itr.GetSource()))
+                        if (GetMap().IsRaid() || group.SameSubGroup(player, groupRef.GetSource()))
-                            m_tapList.Add(itr.GetSource().GetGUID());
+                            m_tapList.Add(groupRef.GetSource().GetGUID());
             }
 
             if (m_tapList.Count >= SharedConst.CreatureTappersSoftCap)

Source/Game/Entities/GameObject/GameObject.cs

@@ -1966,10 +1966,9 @@ namespace Game.Entities
                         Group group = player.GetGroup();
                         if (group != null)
                         {
-                            for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                            foreach (GroupReference groupRef in group.GetMembers())
                             {
-                                Player member = refe.GetSource();
+                                Player member = groupRef.GetSource();
-                                if (member != null)
                                 if (member.IsAtGroupRewardDistance(this))
                                     member.KillCreditGO(info.entry, GetGUID());
                             }

Source/Game/Entities/Object/WorldObject.cs

@@ -3763,6 +3763,11 @@ namespace Game.Entities
 
         public void SetLocationInstanceId(uint _instanceId) { instanceId = _instanceId; }
 
+        public override string ToString()
+        {
+            return GetName();
+        }
+
         #region Fields
         public TypeMask ObjectTypeMask { get; set; }
         protected TypeId ObjectTypeId { get; set; }

Source/Game/Entities/Player/KillRewarder.cs

@@ -104,11 +104,9 @@ namespace Game.Entities
             if (group != null)
             {
                 // 2. In case when player is in group, initialize variables necessary for group calculations:
-                for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
-                {
-                    Player member = refe.GetSource();
-                    if (member != null)
                 {
+                    Player member = groupRef.GetSource();
                     if (killer == member || (member.IsAtGroupRewardDistance(_victim) && member.IsAlive()))
                     {
                         uint lvl = member.GetLevel();
@@ -126,7 +124,6 @@ namespace Game.Entities
                             _maxNotGrayMember = member;
                     }
                 }
-                }
                 // 2.5. _isFullXP - flag identifying that for all group members victim is not gray,
                 //      so 100% XP will be rewarded (50% otherwise).
                 _isFullXP = _maxNotGrayMember != null && (_maxLevel == _maxNotGrayMember.GetLevel());
@@ -254,11 +251,9 @@ namespace Game.Entities
                         _groupRate = Formulas.XPInGroupRate(_count, isRaid);
                     }
                     // 3.1.3. Reward each group member (even dead or corpse) within reward distance.
-                    for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
-                    {
-                        Player member = refe.GetSource();
-                        if (member != null)
                     {
+                        Player member = groupRef.GetSource();
                         // Killer may not be at reward distance, check directly
                         if (killer == member || member.IsAtGroupRewardDistance(_victim))
                             _RewardPlayer(member, isDungeon);
@@ -268,4 +263,3 @@ namespace Game.Entities
         }
     }
 }
-}

Source/Game/Entities/Player/Player.Combat.cs

@@ -40,12 +40,9 @@ namespace Game.Entities
             Group group = GetGroup();
             if (group != null)
             {
-                for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
                 {
-                    Player player = refe.GetSource();
+                    Player player = groupRef.GetSource();
-                    if (player == null)
-                        continue;
-
                     if (!player.IsAtGroupRewardDistance(pRewardSource))
                         continue;                               // member (alive or dead) or his corpse at req. distance
 

Source/Game/Entities/Player/Player.Groups.cs

@@ -18,14 +18,14 @@ namespace Game.Entities
 
             List<Player> nearMembers = new();
 
-            for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
             {
-                Player Target = refe.GetSource();
+                Player target = groupRef.GetSource();
 
                 // IsHostileTo check duel and controlled by enemy
-                if (Target != null && Target != this && IsWithinDistInMap(Target, radius) &&
+                if (target != this && IsWithinDistInMap(target, radius) &&
-                    !Target.HasInvisibilityAura() && !IsHostileTo(Target))
+                    !target.HasInvisibilityAura() && !IsHostileTo(target))
-                    nearMembers.Add(Target);
+                    nearMembers.Add(target);
             }
 
             if (nearMembers.Empty())
@@ -37,13 +37,13 @@ namespace Game.Entities
 
         public PartyResult CanUninviteFromGroup(ObjectGuid guidMember, byte? partyIndex)
         {
-            Group grp = GetGroup(partyIndex);
+            Group group = GetGroup(partyIndex);
-            if (grp == null)
+            if (group == null)
                 return PartyResult.NotInGroup;
 
-            if (grp.IsLFGGroup())
+            if (group.IsLFGGroup())
             {
-                ObjectGuid gguid = grp.GetGUID();
+                ObjectGuid gguid = group.GetGUID();
                 if (Global.LFGMgr.GetKicksLeft(gguid) == 0)
                     return PartyResult.PartyLfgBootLimit;
 
@@ -51,7 +51,7 @@ namespace Game.Entities
                 if (Global.LFGMgr.IsVoteKickActive(gguid))
                     return PartyResult.PartyLfgBootInProgress;
 
-                if (grp.GetMembersCount() <= SharedConst.LFGKickVotesNeeded)
+                if (group.GetMembersCount() <= SharedConst.LFGKickVotesNeeded)
                     return PartyResult.PartyLfgBootTooFewPlayers;
 
                 if (state == LfgState.FinishedDungeon)
@@ -62,8 +62,8 @@ namespace Game.Entities
                     return PartyResult.PartyLfgBootLootRolls;
 
                 // @todo Should also be sent when anyone has recently left combat, with an aprox ~5 seconds timer.
-                for (GroupReference refe = grp.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
-                    if (refe.GetSource() != null && refe.GetSource().IsInMap(this) && refe.GetSource().IsInCombat())
+                    if (groupRef.GetSource().IsInMap(this) && groupRef.GetSource().IsInCombat())
                         return PartyResult.PartyLfgBootInCombat;
 
                 /* Missing support for these types
@@ -73,13 +73,13 @@ namespace Game.Entities
             }
             else
             {
-                if (!grp.IsLeader(GetGUID()) && !grp.IsAssistant(GetGUID()))
+                if (!group.IsLeader(GetGUID()) && !group.IsAssistant(GetGUID()))
                     return PartyResult.NotLeader;
 
                 if (InBattleground())
                     return PartyResult.InviteRestricted;
 
-                if (grp.IsLeader(guidMember))
+                if (group.IsLeader(guidMember))
                     return PartyResult.NotLeader;
             }
 

Source/Game/Entities/Player/Player.Quest.cs

@@ -2442,12 +2442,11 @@ namespace Game.Entities
             var group = GetGroup();
             if (group != null)
             {
-                for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
                 {
-                    Player player = refe.GetSource();
+                    Player player = groupRef.GetSource();
-
                     // for any leave or dead (with not released body) group member at appropriate distance
-                    if (player != null && player.IsAtGroupRewardDistance(pEventObject) && player.GetCorpse() == null)
+                    if (player.IsAtGroupRewardDistance(pEventObject) && player.GetCorpse() == null)
                         player.AreaExploredOrEventHappens(questId);
                 }
             }

Source/Game/Entities/Player/Player.cs

@@ -147,6 +147,9 @@ namespace Game.Entities
 
             WorldMgr.DecreasePlayerCount();
 
+            m_group.Dispose();
+            m_originalGroup.Dispose();
+
             base.Dispose();
         }
 
@@ -7531,12 +7534,9 @@ namespace Game.Entities
                 Group group = GetGroup();
                 if (group != null)
                 {
-                    for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
-                        Player player = refe.GetSource();
+                        Player player = groupRef.GetSource();
-                        if (player == null)
-                            continue;
-
                         if (!player.IsAtRecruitAFriendDistance(this))
                             continue;                               // member (alive or dead) or his corpse at req. distance
 

Source/Game/Entities/Totem.cs

@@ -123,10 +123,10 @@ namespace Game.Entities
                 Group group = owner.GetGroup();
                 if (group != null)
                 {
-                    for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
-                        Player target = refe.GetSource();
+                        Player target = groupRef.GetSource();
-                        if (target != null && target.IsInMap(owner) && group.SameSubGroup(owner, target))
+                        if (target.IsInMap(owner) && group.SameSubGroup(owner, target))
                             target.RemoveAurasDueToSpell(GetSpell(), GetGUID());
                     }
                 }

Source/Game/Entities/Unit/Unit.cs

@@ -3382,11 +3382,9 @@ namespace Game.Entities
             List<Unit> nearMembers = new();
             // reserve place for players and pets because resizing vector every unit push is unefficient (vector is reallocated then)
 
-            for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
-            {
-                Player target = refe.GetSource();
-                if (target != null)
             {
+                Player target = groupRef.GetSource();
                 // IsHostileTo check duel and controlled by enemy
                 if (target != this && IsWithinDistInMap(target, radius) && target.IsAlive() && !IsHostileTo(target))
                     nearMembers.Add(target);
@@ -3397,7 +3395,6 @@ namespace Game.Entities
                     if (pet != this && IsWithinDistInMap(pet, radius) && pet.IsAlive() && !IsHostileTo(pet))
                         nearMembers.Add(pet);
             }
-            }
 
             if (nearMembers.Empty())
                 return null;

Source/Game/Groups/Group.cs

@@ -487,14 +487,12 @@ namespace Game.Groups
                 UpdateObject groupDataPacket;
 
                 // Broadcast group members' fields to player
-                for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in GetMembers())
                 {
-                    if (refe.GetSource() == player)
+                    Player existingMember = groupRef.GetSource();
+                    if (existingMember == player)
                         continue;
 
-                    Player existingMember = refe.GetSource();
-                    if (existingMember != null)
-                    {
                     if (player.HaveAtClient(existingMember))
                         existingMember.BuildValuesUpdateBlockForPlayerWithFlag(groupData, UpdateFieldFlag.PartyMember, player);
 
@@ -510,7 +508,6 @@ namespace Game.Groups
                         }
                     }
                 }
-                }
 
                 if (groupData.HasData())
                 {
@@ -531,11 +528,9 @@ namespace Game.Groups
             Player player = Global.ObjAccessor.FindConnectedPlayer(guid);
             if (player != null)
             {
-                for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in GetMembers())
-                {
-                    Player groupMember = refe.GetSource();
-                    if (groupMember != null)
                 {
+                    Player groupMember = groupRef.GetSource();
                     if (groupMember.GetGUID() == guid)
                         continue;
 
@@ -543,7 +538,6 @@ namespace Game.Groups
                     player.RemoveAllGroupBuffsFromCaster(groupMember.GetGUID());
                 }
             }
-            }
 
             // LFG group vote kick handled in scripts
             if (IsLFGGroup() && method == RemoveMethod.Kick)
@@ -925,37 +919,36 @@ namespace Game.Groups
             PartyMemberFullState packet = new();
             packet.Initialize(player);
 
-            for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in GetMembers())
             {
-                Player member = refe.GetSource();
+                Player member = groupRef.GetSource();
-                if (member != null && member != player && (!member.IsInMap(player) || !member.IsWithinDist(player, member.GetSightRange(), false)))
+                if (member != player && (!member.IsInMap(player) || !member.IsWithinDist(player, member.GetSightRange(), false)))
                     member.SendPacket(packet);
             }
         }
 
         public void BroadcastAddonMessagePacket(ServerPacket packet, string prefix, bool ignorePlayersInBGRaid, int group = -1, ObjectGuid ignore = default)
         {
-            for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in GetMembers())
             {
-                Player player = refe.GetSource();
+                Player player = groupRef.GetSource();
-                if (player == null || (!ignore.IsEmpty() && player.GetGUID() == ignore) || (ignorePlayersInBGRaid && player.GetGroup() != this))
+                if ((!ignore.IsEmpty() && player.GetGUID() == ignore) || (ignorePlayersInBGRaid && player.GetGroup() != this))
                     continue;
 
-                if ((group == -1 || refe.GetSubGroup() == group))
+                if (player.GetSession().IsAddonRegistered(prefix) && (group == -1 || groupRef.GetSubGroup() == group))
-                    if (player.GetSession().IsAddonRegistered(prefix))
                     player.SendPacket(packet);
             }
         }
 
         public void BroadcastPacket(ServerPacket packet, bool ignorePlayersInBGRaid, int group = -1, ObjectGuid ignore = default)
         {
-            for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in GetMembers())
             {
-                Player player = refe.GetSource();
+                Player player = groupRef.GetSource();
-                if (player == null || (!ignore.IsEmpty() && player.GetGUID() == ignore) || (ignorePlayersInBGRaid && player.GetGroup() != this))
+                if ((!ignore.IsEmpty() && player.GetGUID() == ignore) || (ignorePlayersInBGRaid && player.GetGroup() != this))
                     continue;
 
-                if (player.GetSession() != null && (group == -1 || refe.GetSubGroup() == group))
+                if (group == -1 || groupRef.GetSubGroup() == group)
                     player.SendPacket(packet);
             }
         }
@@ -1183,11 +1176,12 @@ namespace Game.Groups
                 return GroupJoinBattlegroundResult.None;                        // ERR_GROUP_JOIN_Battleground_TOO_MANY handled on client side
 
             // get a player as reference, to compare other players' stats to (arena team id, queue id based on level, etc.)
-            Player reference = GetFirstMember().GetSource();
+            var membersRefe = GetMembers().GetFirst();
             // no reference found, can't join this way
-            if (reference == null)
+            if (membersRefe == null)
                 return GroupJoinBattlegroundResult.BattlegroundJoinFailed;
 
+            Player reference = membersRefe.GetSource();
             PvpDifficultyRecord bracketEntry = Global.DB2Mgr.GetBattlegroundBracketByLevel((uint)bgOrTemplate.MapIDs[0], reference.GetLevel());
             if (bracketEntry == null)
                 return GroupJoinBattlegroundResult.BattlegroundJoinFailed;
@@ -1198,9 +1192,9 @@ namespace Game.Groups
 
             // check every member of the group to be able to join
             memberscount = 0;
-            for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next(), ++memberscount)
+            foreach (GroupReference groupRef in GetMembers())
             {
-                Player member = refe.GetSource();
+                Player member = groupRef.GetSource();
                 // offline member? don't let join
                 if (member == null)
                     return GroupJoinBattlegroundResult.BattlegroundJoinFailed;
@@ -1243,6 +1237,8 @@ namespace Game.Groups
                     return GroupJoinBattlegroundResult.BattlegroundJoinFailed;
                 if (isMercenary != (member.HasAura(BattlegroundConst.SpellMercenaryContractHorde) || member.HasAura(BattlegroundConst.SpellMercenaryContractAlliance)))
                     return GroupJoinBattlegroundResult.BattlegroundJoinMercenary;
+
+                memberscount++;
             }
 
             errorGuid = ObjectGuid.Empty;
@@ -1267,12 +1263,9 @@ namespace Game.Groups
                 DB.Characters.Execute(stmt);
             }
 
-            for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in GetMembers())
             {
-                Player player = refe.GetSource();
+                Player player = groupRef.GetSource();
-                if (player.GetSession() == null)
-                    continue;
-
                 player.SetDungeonDifficultyID(difficulty);
                 player.SendDungeonDifficulty();
             }
@@ -1291,12 +1284,9 @@ namespace Game.Groups
                 DB.Characters.Execute(stmt);
             }
 
-            for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in GetMembers())
             {
-                Player player = refe.GetSource();
+                Player player = groupRef.GetSource();
-                if (player.GetSession() == null)
-                    continue;
-
                 player.SetRaidDifficultyID(difficulty);
                 player.SendRaidDifficulty(false);
             }
@@ -1315,12 +1305,9 @@ namespace Game.Groups
                 DB.Characters.Execute(stmt);
             }
 
-            for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in GetMembers())
             {
-                Player player = refe.GetSource();
+                Player player = groupRef.GetSource();
-                if (player.GetSession() == null)
-                    continue;
-
                 player.SetLegacyRaidDifficultyID(difficulty);
                 player.SendRaidDifficulty(true);
             }
@@ -1348,9 +1335,9 @@ namespace Game.Groups
 
         public void ResetInstances(InstanceResetMethod method, Player notifyPlayer)
         {
-            for (GroupInstanceReference refe = m_ownedInstancesMgr.GetFirst(); refe != null; refe = refe.Next())
+            foreach (GroupInstanceReference groupInstanceRef in m_ownedInstancesMgr)
             {
-                InstanceMap map = refe.GetSource();
+                InstanceMap map = groupInstanceRef.GetSource();
                 switch (map.Reset(method))
                 {
                     case InstanceResetResult.Success:
@@ -1795,19 +1782,9 @@ namespace Game.Groups
             m_memberMgr.InsertFirst(pRef);
         }
 
-        void DelinkMember(ObjectGuid guid)
+        public void DelinkMember(ObjectGuid guid)
         {
-            GroupReference refe = m_memberMgr.GetFirst();
+            m_memberMgr.Remove(p => p.GetSource().GetGUID() == guid);
-            while (refe != null)
-            {
-                GroupReference nextRef = refe.Next();
-                if (refe.GetSource().GetGUID() == guid)
-                {
-                    refe.Unlink();
-                    break;
-                }
-                refe = nextRef;
-            }
         }
 
         void _initRaidSubGroupsCounter()
@@ -1915,7 +1892,7 @@ namespace Game.Groups
 
         public uint GetDbStoreId() { return m_dbStoreId; }
         public List<MemberSlot> GetMemberSlots() { return m_memberSlots; }
-        public GroupReference GetFirstMember() { return (GroupReference)m_memberMgr.GetFirst(); }
+        public GroupRefManager GetMembers() { return m_memberMgr; }
         public uint GetMembersCount() { return (uint)m_memberSlots.Count; }
         public uint GetInviteeCount() { return (uint)m_invitees.Count; }
         public GroupFlags GetGroupFlags() { return m_groupFlags; }
@@ -1924,8 +1901,8 @@ namespace Game.Groups
 
         public void BroadcastWorker(Action<Player> worker)
         {
-            for (GroupReference refe = GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in GetMembers())
-                worker(refe.GetSource());
+                worker(groupRef.GetSource());
         }
 
         public ObjectGuid GetRecentInstanceOwner(uint mapId)

Source/Game/Groups/GroupInstanceReference.cs

@@ -8,9 +8,7 @@ namespace Game.Groups
 {
     public class GroupInstanceReference : Reference<Group, InstanceMap>
     {
-        ~GroupInstanceReference() { Unlink(); }
+        public void Dispose() { Unlink(); }
-
-        public new GroupInstanceReference Next() { return (GroupInstanceReference)base.Next(); }
 
         public override void TargetObjectBuildLink()
         {
@@ -18,8 +16,5 @@ namespace Game.Groups
         }
     }
 
-    class GroupInstanceRefManager : RefManager<Group, InstanceMap>
+    class GroupInstanceRefManager : RefManager<GroupInstanceReference> { }
-    {
-        public new GroupInstanceReference GetFirst() { return (GroupInstanceReference)base.GetFirst(); }
-    }
 }

Source/Game/Groups/GroupReference.cs

@@ -13,14 +13,17 @@ namespace Game.Groups
             iSubGroup = 0;
         }
 
-        ~GroupReference() { Unlink(); }
+        public void Dispose() { Unlink(); }
 
         public override void TargetObjectBuildLink()
         {
             GetTarget().LinkMember(this);
         }
 
-        public new GroupReference Next() { return (GroupReference)base.Next(); }
+        public override void TargetObjectDestroyLink()
+        {
+            GetTarget()?.DelinkMember(GetSource().GetGUID());
+        }
 
         public byte GetSubGroup() { return iSubGroup; }
 
@@ -29,8 +32,5 @@ namespace Game.Groups
         byte iSubGroup;
     }
 
-    public class GroupRefManager : RefManager<Group, Player>
+    public class GroupRefManager : RefManager<GroupReference> { }
-    {
-        public new GroupReference GetFirst() { return (GroupReference)base.GetFirst(); }
-    }
 }

Source/Game/Handlers/BattleGroundHandler.cs

@@ -86,7 +86,7 @@ namespace Game
 
             GroupJoinBattlegroundResult err = GroupJoinBattlegroundResult.None;
 
-            Group grp = _player.GetGroup();
+            Group group = _player.GetGroup();
 
             Team getQueueTeam()
             {
@@ -105,7 +105,7 @@ namespace Game
 
             BattlefieldStatusFailed battlefieldStatusFailed;
             // check queue conditions
-            if (grp == null)
+            if (group == null)
             {
                 if (GetPlayer().IsUsingLfg())
                 {
@@ -177,12 +177,12 @@ namespace Game
             }
             else
             {
-                if (grp.GetLeaderGUID() != GetPlayer().GetGUID())
+                if (group.GetLeaderGUID() != GetPlayer().GetGUID())
                     return;
 
                 ObjectGuid errorGuid;
-                err = grp.CanJoinBattlegroundQueue(bgTemplate, bgQueueTypeId, 0, bgTemplate.GetMaxPlayersPerTeam(), false, 0, out errorGuid);
+                err = group.CanJoinBattlegroundQueue(bgTemplate, bgQueueTypeId, 0, bgTemplate.GetMaxPlayersPerTeam(), false, 0, out errorGuid);
-                isPremade = (grp.GetMembersCount() >= bgTemplate.GetMinPlayersPerTeam());
+                isPremade = (group.GetMembersCount() >= bgTemplate.GetMinPlayersPerTeam());
 
                 BattlegroundQueue bgQueue = Global.BattlegroundMgr.GetBattlegroundQueue(bgQueueTypeId);
                 GroupQueueInfo ginfo = null;
@@ -191,16 +191,13 @@ namespace Game
                 if (err == 0)
                 {
                     Log.outDebug(LogFilter.Battleground, "Battleground: the following players are joining as group:");
-                    ginfo = bgQueue.AddGroup(GetPlayer(), grp, getQueueTeam(), bracketEntry, isPremade, 0, 0);
+                    ginfo = bgQueue.AddGroup(GetPlayer(), group, getQueueTeam(), bracketEntry, isPremade, 0, 0);
                     avgTime = bgQueue.GetAverageQueueWaitTime(ginfo, bracketEntry.GetBracketId());
                 }
 
-                for (GroupReference refe = grp.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
                 {
-                    Player member = refe.GetSource();
+                    Player member = groupRef.GetSource();
-                    if (member == null)
-                        continue;   // this should never happen
-
                     if (err != 0)
                     {
                         BattlefieldStatusFailed battlefieldStatus;
@@ -510,11 +507,11 @@ namespace Game
             if (bracketEntry == null)
                 return;
 
-            Group grp = GetPlayer().GetGroup();
+            Group group = GetPlayer().GetGroup();
             // no group found, error
-            if (grp == null)
+            if (group == null)
                 return;
-            if (grp.GetLeaderGUID() != GetPlayer().GetGUID())
+            if (group.GetLeaderGUID() != GetPlayer().GetGUID())
                 return;
 
             uint ateamId = GetPlayer().GetArenaTeamId(packet.TeamSizeIndex);
@@ -525,7 +522,7 @@ namespace Game
 
             // get the team rating for queuing
             uint arenaRating = at.GetRating();
-            uint matchmakerRating = at.GetAverageMMR(grp);
+            uint matchmakerRating = at.GetAverageMMR(group);
             // the arenateam id must match for everyone in the group
 
             if (arenaRating <= 0)
@@ -537,21 +534,18 @@ namespace Game
             GroupQueueInfo ginfo = null;
 
             ObjectGuid errorGuid;
-            var err = grp.CanJoinBattlegroundQueue(bgTemplate, bgQueueTypeId, (uint)arenatype, (uint)arenatype, true, packet.TeamSizeIndex, out errorGuid);
+            var err = group.CanJoinBattlegroundQueue(bgTemplate, bgQueueTypeId, (uint)arenatype, (uint)arenatype, true, packet.TeamSizeIndex, out errorGuid);
             if (err == 0)
             {
                 Log.outDebug(LogFilter.Battleground, "Battleground: arena team id {0}, leader {1} queued with matchmaker rating {2} for type {3}", GetPlayer().GetArenaTeamId(packet.TeamSizeIndex), GetPlayer().GetName(), matchmakerRating, arenatype);
 
-                ginfo = bgQueue.AddGroup(GetPlayer(), grp, _player.GetTeam(), bracketEntry, false, arenaRating, matchmakerRating, ateamId);
+                ginfo = bgQueue.AddGroup(GetPlayer(), group, _player.GetTeam(), bracketEntry, false, arenaRating, matchmakerRating, ateamId);
                 avgTime = bgQueue.GetAverageQueueWaitTime(ginfo, bracketEntry.GetBracketId());
             }
 
-            for (GroupReference refe = grp.GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
             {
-                Player member = refe.GetSource();
+                Player member = groupRef.GetSource();
-                if (member == null)
-                    continue;
-
                 if (err != 0)
                 {
                     BattlefieldStatusFailed battlefieldStatus;

Source/Game/Handlers/GroupHandler.cs

@@ -158,7 +158,7 @@ namespace Game
             if (group == null)
                 return;
 
-            if (packet.PartyIndex != 0 && group.GetGroupCategory() != (GroupCategory)packet.PartyIndex)
+            if (packet.PartyIndex.HasValue && group.GetGroupCategory() != (GroupCategory)packet.PartyIndex)
                 return;
 
             if (packet.Accept)
@@ -702,9 +702,9 @@ namespace Game
             broadcastPingUnit.SpellOverrideNameID = pingUnit.SpellOverrideNameID;
             broadcastPingUnit.Write();
 
-            for (GroupReference itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
             {
-                Player member = itr.GetSource();
+                Player member = groupRef.GetSource();
                 if (_player == member || !_player.IsInMap(member))
                     continue;
 
@@ -732,9 +732,9 @@ namespace Game
             broadcastPingWorldPoint.PingDuration = pingWorldPoint.PingDuration;
             broadcastPingWorldPoint.Write();
 
-            for (GroupReference itr = group.GetFirstMember(); itr != null; itr = itr.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
             {
-                Player member = itr.GetSource();
+                Player member = groupRef.GetSource();
                 if (_player == member || !_player.IsInMap(member))
                     continue;
 

Source/Game/Handlers/LFGHandler.cs

@@ -205,12 +205,9 @@ namespace Game
             LfgPartyInfo lfgPartyInfo = new();
 
             // Get the Locked dungeons of the other party members
-            for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
             {
-                Player plrg = refe.GetSource();
+                Player plrg = groupRef.GetSource();
-                if (plrg == null)
-                    continue;
-
                 ObjectGuid pguid = plrg.GetGUID();
                 if (pguid == guid)
                     continue;

Source/Game/Handlers/LootHandler.cs

@@ -99,12 +99,9 @@ namespace Game
                     Group group = player.GetGroup();
 
                     List<Player> playersNear = new();
-                    for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
-                        Player member = refe.GetSource();
+                        Player member = groupRef.GetSource();
-                        if (member == null)
-                            continue;
-
                         if (!loot.HasAllowedLooter(member.GetGUID()))
                             continue;
 

Source/Game/Handlers/QuestHandler.cs

@@ -126,11 +126,10 @@ namespace Game
                 var group = _player.GetGroup();
                 if (group != null)
                 {
-                    for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                    foreach (GroupReference groupRef in group.GetMembers())
                     {
-                        Player player = refe.GetSource();
+                        Player player = groupRef.GetSource();
-
+                        if (player == _player || !player.IsInMap(_player))     // not self and in same map
-                        if (player == null || player == _player || !player.IsInMap(_player))     // not self and in same map
                             continue;
 
                         if (player.CanTakeQuest(quest, true))
@@ -551,11 +550,10 @@ namespace Game
                 return;
             }
 
-            for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+            foreach (GroupReference groupRef in group.GetMembers())
             {
-                Player receiver = refe.GetSource();
+                Player receiver = groupRef.GetSource();
-
+                if (receiver == sender)
-                if (receiver == null || receiver == sender)
                     continue;
 
                 if (!receiver.GetPlayerSharingQuest().IsEmpty())

Source/Game/Loot/Loot.cs

@@ -936,10 +936,9 @@ namespace Game.Loots
                 if (loot_type == LootType.Corpse)
                     roundRobinPlayer = lootOwner.GetGUID();
 
-                for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
                 {
-                    Player player = refe.GetSource();
+                    Player player = groupRef.GetSource();// should actually be looted object instead of lootOwner but looter has to be really close so doesnt really matter
-                    if (player != null)   // should actually be looted object instead of lootOwner but looter has to be really close so doesnt really matter
                     if (player.IsAtGroupRewardDistance(lootOwner))
                         FillNotNormalLootFor(player);
                 }

Source/Game/Maps/Map.cs

@@ -3,7 +3,6 @@
 
 using Framework.Constants;
 using Framework.Database;
-using Framework.Dynamic;
 using Game.BattleGrounds;
 using Game.Collision;
 using Game.DataStorage;
@@ -15,7 +14,6 @@ using Game.Scenarios;
 using System;
 using System.Collections;
 using System.Collections.Generic;
-using System.IO;
 using System.Linq;
 using System.Numerics;
 
@@ -62,7 +60,7 @@ namespace Game.Maps
             _worldStateValues = Global.WorldStateMgr.GetInitialWorldStatesForMap(this);
         }
 
-        public void Dispose()
+        public virtual void Dispose()
         {
             // Delete all waiting spawns
             // This doesn't delete from database.
@@ -389,7 +387,6 @@ namespace Game.Maps
             }
         }
 
-
         public void AddInfiniteAOIVignette(VignetteData vignette)
         {
             _infiniteAOIVignettes.Add(vignette);
@@ -4905,10 +4902,14 @@ namespace Game.Maps
             }
         }
 
-        ~InstanceMap()
+        public override void Dispose()
         {
             if (i_instanceLock != null)
                 i_instanceLock.SetInUse(false);
+
+            i_owningGroupRef.Dispose();
+
+            base.Dispose();
         }
 
         public override void InitVisibilityDistance()
@@ -5339,6 +5340,18 @@ namespace Game.Maps
             InitVisibilityDistance();
         }
 
+        public override void Dispose()
+        {
+            if (m_bg != null)
+            {
+                //unlink to prevent crash, always unlink all pointer reference before destruction
+                m_bg.SetBgMap(null);
+                m_bg.Dispose();
+            }
+
+            base.Dispose();
+        }
+
         public override void InitVisibilityDistance()
         {
             m_VisibleDistance = IsBattleArena() ? Global.WorldMgr.GetMaxVisibleDistanceInArenas() : Global.WorldMgr.GetMaxVisibleDistanceInBG();

Source/Game/OutdoorPVP/OutdoorPvP.cs

@@ -61,12 +61,9 @@ namespace Game.PvP
             Group group = killer.GetGroup();
             if (group != null)
             {
-                for (GroupReference refe = group.GetFirstMember(); refe != null; refe = refe.Next())
+                foreach (GroupReference groupRef in group.GetMembers())
                 {
-                    Player groupGuy = refe.GetSource();
+                    Player groupGuy = groupRef.GetSource();
-
-                    if (groupGuy == null)
-                        continue;
 
                     // skip if too far away
                     if (!groupGuy.IsAtGroupRewardDistance(killed))