Core/Scripts: Added support for creating custom GameObjectAI classes, similar to how creature scripts work.

src/server/game/AI/CreatureAISelector.cpp

@@ -133,6 +133,9 @@ namespace FactorySelector
         const GameObjectAICreator* ai_factory = NULL;
         GameObjectAIRegistry& ai_registry(*GameObjectAIRepository::instance());
 
+        if (GameObjectAI* scriptedAI = sScriptMgr->GetGameObjectAI(go))
+            return scriptedAI;
+
         ai_factory = ai_registry.GetRegistryItem(go->GetAIName());
 
         //future goAI types go here

src/server/game/Scripting/ScriptMgr.cpp

@@ -954,6 +954,14 @@ bool ScriptMgr::OnDummyEffect(Unit* caster, uint32 spellId, SpellEffIndex effInd
     return tmpscript->OnDummyEffect(caster, spellId, effIndex, target);
 }
 
+GameObjectAI* ScriptMgr::GetGameObjectAI(GameObject* go)
+{
+    ASSERT(go);
+
+    GET_SCRIPT_RET(GameObjectScript, go->GetScriptId(), tmpscript, NULL);
+    tmpscript->GetAI(go);
+}
+
 bool ScriptMgr::OnAreaTrigger(Player* player, AreaTriggerEntry const* trigger)
 {
     ASSERT(player);

src/server/game/Scripting/ScriptMgr.h

@@ -39,6 +39,7 @@ class Creature;
 class CreatureAI;
 class DynamicObject;
 class GameObject;
+class GameObjectAI;
 class Guild;
 class GridMap;
 class Group;
@@ -471,6 +472,9 @@ class GameObjectScript : public ScriptObject, public UpdatableScript<GameObject>
 
         // Called when the game object is damaged (destructible buildings only).
         virtual void OnDamaged(GameObject* /*go*/, Player* /*player*/) { }
+
+        // Called when a GameObjectAI object is needed for the gameobject.
+        virtual GameObjectAI* GetAI(GameObject* /*go*/) const { return NULL; }
 };
 
 class AreaTriggerScript : public ScriptObject
@@ -911,6 +915,7 @@ class ScriptMgr
         void OnGameObjectDestroyed(GameObject* go, Player* player);
         void OnGameObjectDamaged(GameObject* go, Player* player);
         void OnGameObjectUpdate(GameObject* go, uint32 diff);
+        GameObjectAI* GetGameObjectAI(GameObject* go);
 
     public: /* AreaTriggerScript */
 

src/server/scripts/Northrend/Ulduar/Ulduar/instance_ulduar.cpp

@@ -234,7 +234,6 @@ class instance_ulduar : public InstanceMapScript
                     case NPC_ALGALON:
                         AlgalonGUID = creature->GetGUID();
                         break;
-
                     // Hodir's Helper NPCs
                     case NPC_EIVI_NIGHTFEATHER:
                         if (TeamInInstance == HORDE)