Core/BG:

- Force removal of stealth and invisible auras when using gameobjects with type GAMEOBJECT_TYPE_FLAGSTAND and GAMEOBJECT_TYPE_FLAGDROP
- Do not allow players to use unfriendly battleground objects (prevents flag cap with Nitro Boosts active for example)

src/server/game/Entities/GameObject/GameObject.cpp

@@ -1522,14 +1522,18 @@ void GameObject::Use(Unit* user)
 
             Player* player = user->ToPlayer();
 
-            if (player->CanUseBattlegroundObject())
+            if (player->CanUseBattlegroundObject(this))
             {
                 // in battleground check
                 Battleground* bg = player->GetBattleground();
                 if (!bg)
                     return;
+
                 if (player->GetVehicle())
                     return;
+
+                player->RemoveAurasByType(SPELL_AURA_MOD_STEALTH);
+                player->RemoveAurasByType(SPELL_AURA_MOD_INVISIBILITY);
                 // BG flag click
                 // AB:
                 // 15001
@@ -1562,14 +1566,18 @@ void GameObject::Use(Unit* user)
 
             Player* player = user->ToPlayer();
 
-            if (player->CanUseBattlegroundObject())
+            if (player->CanUseBattlegroundObject(this))
             {
                 // in battleground check
                 Battleground* bg = player->GetBattleground();
                 if (!bg)
                     return;
+
                 if (player->GetVehicle())
                     return;
+
+                player->RemoveAurasByType(SPELL_AURA_MOD_STEALTH);
+                player->RemoveAurasByType(SPELL_AURA_MOD_INVISIBILITY);
                 // BG flag dropped
                 // WS:
                 // 179785 - Silverwing Flag

src/server/game/Entities/Player/Player.cpp

@@ -23488,10 +23488,14 @@ WorldObject* Player::GetViewpoint() const
     return NULL;
 }
 
-bool Player::CanUseBattlegroundObject()
+bool Player::CanUseBattlegroundObject(GameObject* gameobject)
 {
-    // TODO : some spells gives player ForceReaction to one faction (ReputationMgr::ApplyForceReaction)
-    // maybe gameobject code should handle that ForceReaction usage
+    FactionTemplateEntry const* playerFaction = getFactionTemplateEntry();
+    FactionTemplateEntry const* faction = sFactionTemplateStore.LookupEntry(gameobject->GetUInt32Value(GAMEOBJECT_FACTION));
+
+    if (playerFaction && faction && !playerFaction->IsFriendlyTo(*faction))
+        return false;
+
     // BUG: sometimes when player clicks on flag in AB - client won't send gameobject_use, only gameobject_report_use packet
     // Note: Mount, stealth and invisibility will be removed when used
     return (!isTotalImmune() &&                            // Damage immune

src/server/game/Entities/Player/Player.h

@@ -2237,7 +2237,7 @@ class Player : public Unit, public GridObject<Player>
 
         bool GetBGAccessByLevel(BattlegroundTypeId bgTypeId) const;
         bool isTotalImmunity();
-        bool CanUseBattlegroundObject();
+        bool CanUseBattlegroundObject(GameObject* gameobject);
         bool isTotalImmune();
         bool CanCaptureTowerPoint();
 

src/server/game/Spells/Spell.cpp

@@ -5210,7 +5210,7 @@ SpellCastResult Spell::CheckCast(bool strict)
                 if (m_spellInfo->Id != 1842 || (m_targets.GetGOTarget() &&
                     m_targets.GetGOTarget()->GetGOInfo()->type != GAMEOBJECT_TYPE_TRAP))
                     if (m_caster->ToPlayer()->InBattleground() && // In Battleground players can use only flags and banners
-                        !m_caster->ToPlayer()->CanUseBattlegroundObject())
+                        !m_caster->ToPlayer()->CanUseBattlegroundObject(m_targets.GetGOTarget()))
                         return SPELL_FAILED_TRY_AGAIN;
 
                 // get the lock entry