Core/Maps: Made instance_template no longer required to create and enter instance maps

src/server/game/Globals/ObjectMgr.cpp

@@ -5536,7 +5536,7 @@ void ObjectMgr::LoadInstanceTemplate()
 
         uint16 mapID = fields[0].GetUInt16();
 
-        if (!MapManager::IsValidMAP(mapID, true))
+        if (!MapManager::IsValidMAP(mapID))
         {
             TC_LOG_ERROR("sql.sql", "ObjectMgr::LoadInstanceTemplate: bad mapid %d for template!", mapID);
             continue;
@@ -6753,31 +6753,26 @@ void ObjectMgr::LoadAccessRequirements()
  */
 AreaTriggerStruct const* ObjectMgr::GetGoBackTrigger(uint32 Map) const
 {
-    bool useParentDbValue = false;
-    uint32 parentId = 0;
+    Optional<uint32> parentId;
     MapEntry const* mapEntry = sMapStore.LookupEntry(Map);
     if (!mapEntry || mapEntry->CorpseMapID < 0)
         return nullptr;
 
     if (mapEntry->IsDungeon())
-    {
-        InstanceTemplate const* iTemplate = sObjectMgr->GetInstanceTemplate(Map);
+        if (InstanceTemplate const* iTemplate = sObjectMgr->GetInstanceTemplate(Map))
+            parentId = iTemplate->Parent;
 
-        if (!iTemplate)
-            return nullptr;
+    uint32 entrance_map = parentId.value_or(mapEntry->CorpseMapID);
 
-        parentId = iTemplate->Parent;
-        useParentDbValue = true;
-    }
-
-    uint32 entrance_map = uint32(mapEntry->CorpseMapID);
     for (AreaTriggerContainer::const_iterator itr = _areaTriggerStore.begin(); itr != _areaTriggerStore.end(); ++itr)
-        if ((!useParentDbValue && itr->second.target_mapId == entrance_map) || (useParentDbValue && itr->second.target_mapId == parentId))
+    {
+        if (itr->second.target_mapId == entrance_map)
         {
             AreaTriggerEntry const* atEntry = sAreaTriggerStore.LookupEntry(itr->first);
-            if (atEntry && atEntry->ContinentID == Map)
+            if (atEntry && atEntry->ContinentID == int32(Map))
                 return &itr->second;
         }
+    }
     return nullptr;
 }