Core/Entities: Handle partial state change for pets

Port From (https://github.com/TrinityCore/TrinityCore/commit/0585032c9000386846c506a360eddc09cf069afe)

Source/Game/Entities/TemporarySummon.cs

@@ -321,6 +321,28 @@ namespace Game.Entities
             base.RemoveFromWorld();
         }
 
+        public override void SetDeathState(DeathState s)
+        {
+            base.SetDeathState(s);
+            if (s != DeathState.JustDied || !IsGuardianPet())
+                return;
+
+            Unit owner = GetOwner();
+            if (owner == null || !owner.IsPlayer() || owner.GetMinionGUID() != GetGUID())
+                return;
+
+            foreach (Unit controlled in owner.m_Controlled)
+            {
+                if (controlled.GetEntry() == GetEntry() && controlled.IsAlive())
+                {
+                    owner.SetMinionGUID(controlled.GetGUID());
+                    owner.SetPetGUID(controlled.GetGUID());
+                    owner.ToPlayer().CharmSpellInitialize();
+                    break;
+                }
+            }
+        }
+
         public bool IsGuardianPet()
         {
             return IsPet() || (m_Properties != null && m_Properties.Control == SummonCategory.Pet);

Source/Game/Handlers/PetHandler.cs

@@ -481,6 +481,11 @@ namespace Game
                 return;
             }
 
+            List<Unit> pets = new();
+            foreach (Unit controlled in _player.m_Controlled)
+                if (controlled.GetEntry() == pet.GetEntry() && controlled.IsAlive())
+                    pets.Add(controlled);
+
             uint position = packet.Index;
             uint actionData = packet.Action;
 
@@ -489,34 +494,35 @@ namespace Game
 
             Log.outDebug(LogFilter.Network, "Player {0} has changed pet spell action. Position: {1}, Spell: {2}, State: {3}", GetPlayer().GetName(), position, spell_id, act_state);
 
-
+            foreach (Unit petControlled in pets)
-            //if it's act for spell (en/disable/cast) and there is a spell given (0 = remove spell) which pet doesn't know, don't add
-            if (!((act_state == ActiveStates.Enabled || act_state == ActiveStates.Disabled || act_state == ActiveStates.Passive) && spell_id != 0 && !pet.HasSpell(spell_id)))
             {
-                SpellInfo spellInfo = Global.SpellMgr.GetSpellInfo(spell_id, pet.GetMap().GetDifficultyID());
+                //if it's act for spell (en/disable/cast) and there is a spell given (0 = remove spell) which pet doesn't know, don't add
+                if (!((act_state == ActiveStates.Enabled || act_state == ActiveStates.Disabled || act_state == ActiveStates.Passive) && spell_id != 0 && !petControlled.HasSpell(spell_id)))
+                {
+                    SpellInfo spellInfo = Global.SpellMgr.GetSpellInfo(spell_id, petControlled.GetMap().GetDifficultyID());
                     if (spellInfo != null)
                     {
                         //sign for autocast
                         if (act_state == ActiveStates.Enabled)
                         {
-                        if (pet.GetTypeId() == TypeId.Unit && pet.IsPet())
+                            if (petControlled.GetTypeId() == TypeId.Unit && petControlled.IsPet())
-                            ((Pet)pet).ToggleAutocast(spellInfo, true);
+                                ((Pet)petControlled).ToggleAutocast(spellInfo, true);
                             else
                             {
                                 foreach (var unit in GetPlayer().m_Controlled)
-                                if (unit.GetEntry() == pet.GetEntry())
+                                    if (unit.GetEntry() == petControlled.GetEntry())
                                         unit.GetCharmInfo().ToggleCreatureAutocast(spellInfo, true);
                             }
                         }
                         //sign for no/turn off autocast
                         else if (act_state == ActiveStates.Disabled)
                         {
-                        if (pet.GetTypeId() == TypeId.Unit && pet.IsPet())
+                            if (petControlled.GetTypeId() == TypeId.Unit && petControlled.IsPet())
-                            pet.ToPet().ToggleAutocast(spellInfo, false);
+                                petControlled.ToPet().ToggleAutocast(spellInfo, false);
                             else
                             {
                                 foreach (var unit in GetPlayer().m_Controlled)
-                                if (unit.GetEntry() == pet.GetEntry())
+                                    if (unit.GetEntry() == petControlled.GetEntry())
                                         unit.GetCharmInfo().ToggleCreatureAutocast(spellInfo, false);
                             }
                         }
@@ -525,6 +531,7 @@ namespace Game
                     charmInfo.SetActionBar((byte)position, spell_id, act_state);
                 }
             }
+        }
 
         [WorldPacketHandler(ClientOpcodes.PetRename)]
         void HandlePetRename(PetRename packet)
@@ -623,24 +630,32 @@ namespace Game
                 return;
             }
 
+            List<Unit> pets = new();
+            foreach (Unit controlled in _player.m_Controlled)
+                if (controlled.GetEntry() == pet.GetEntry() && controlled.IsAlive())
+                    pets.Add(controlled);
+
+            foreach (Unit petControlled in pets)
+            {
                 // do not add not learned spells/ passive spells
-            if (!pet.HasSpell(packet.SpellID) || !spellInfo.IsAutocastable())
+                if (!petControlled.HasSpell(packet.SpellID) || !spellInfo.IsAutocastable())
                     return;
 
-            CharmInfo charmInfo = pet.GetCharmInfo();
+                CharmInfo charmInfo = petControlled.GetCharmInfo();
                 if (charmInfo == null)
                 {
-                Log.outError(LogFilter.Network, "WorldSession.HandlePetSpellAutocastOpcod: object {0} is considered pet-like but doesn't have a charminfo!", pet.GetGUID().ToString());
+                    Log.outError(LogFilter.Network, "WorldSession.HandlePetSpellAutocastOpcod: object {0} is considered pet-like but doesn't have a charminfo!", petControlled.GetGUID().ToString());
                     return;
                 }
 
-            if (pet.IsPet())
+                if (petControlled.IsPet())
-                pet.ToPet().ToggleAutocast(spellInfo, packet.AutocastEnabled);
+                    petControlled.ToPet().ToggleAutocast(spellInfo, packet.AutocastEnabled);
                 else
                     charmInfo.ToggleCreatureAutocast(spellInfo, packet.AutocastEnabled);
 
                 charmInfo.SetSpellAutocast(spellInfo, packet.AutocastEnabled);
             }
+        }
 
         [WorldPacketHandler(ClientOpcodes.PetCastSpell, Processing = PacketProcessing.Inplace)]
         void HandlePetCastSpell(PetCastSpell petCastSpell)