Core/Vehicles: Implement VEHICLE_SEAT_FLAG_B_CANSWITCH restriction, and do some cleanup.

src/server/game/DataStores/DBCStructure.h

@@ -1848,6 +1848,7 @@ struct VehicleSeatEntry
                                                             // 46-57 added in 3.1, floats mostly
 
     bool CanEnterOrExit() const { return m_flags & VEHICLE_SEAT_FLAG_CAN_ENTER_OR_EXIT; }
+    bool CanSwitchFromSeat() const { return m_flags & VEHICLE_SEAT_FLAG_B_CANSWITCH; }
     bool IsUsableByAura() const { return m_flagsB & (VEHICLE_SEAT_FLAG_B_USABLE_FORCED | VEHICLE_SEAT_FLAG_B_USABLE_FORCED_2 | VEHICLE_SEAT_FLAG_B_USABLE_FORCED_3); }
     bool IsEjectable() const { return m_flagsB & VEHICLE_SEAT_FLAG_B_EJECTABLE; }
 };

src/server/game/Entities/Vehicle/Vehicle.cpp

@@ -423,17 +423,6 @@ void Vehicle::RemovePassenger(Unit *unit)
         sScriptMgr->OnRemovePassenger(this, unit);
 }
 
-void Vehicle::EjectPassenger(Unit* passenger, Unit* controller)
-{
-    SeatMap::const_iterator m_SeatsItr;
-    for (m_SeatsItr = m_Seats.begin(); m_SeatsItr != m_Seats.end(); ++m_SeatsItr)
-        if (m_SeatsItr->second.passenger == passenger)
-            if (m_SeatsItr->second.seatInfo->IsEjectable())
-                return passenger->ExitVehicle();
-            else
-                sLog->outError("Player %u attempted to eject unit GUID "UI64FMTD" from non-ejectable seat.", controller->GetGUIDLow(), passenger->GetGUID());
-}
-
 void Vehicle::RelocatePassengers(float x, float y, float z, float ang)
 {
     Map *map = me->GetMap();

src/server/game/Server/Protocol/Handlers/MovementHandler.cpp

@@ -548,6 +548,14 @@ void WorldSession::HandleChangeSeatsOnControlledVehicle(WorldPacket &recv_data)
     if (!vehicle_base)
         return;
 
+    VehicleSeatEntry const* seat = GetPlayer()->GetVehicle()->GetSeatForPassenger(GetPlayer());
+    if (!seat->CanSwitchFromSeat())
+    {
+        sLog->outError("HandleChangeSeatsOnControlledVehicle, Opcode: %u, Player %u tried to switch seats but current seatflags %u don't permit that.",
+            recv_data.GetOpcode(), GetPlayer()->GetGUIDLow(), seat->m_flags);
+        return;
+    }
+
     switch (recv_data.GetOpcode())
     {
         case CMSG_REQUEST_VEHICLE_PREV_SEAT:
@@ -635,6 +643,8 @@ void WorldSession::HandleEjectPassenger(WorldPacket &data)
                 VehicleSeatEntry const* seat = vehicle->GetSeatForPassenger(plr);
                 if (seat->IsEjectable())
                     plr->ExitVehicle();
+                else
+                    sLog->outError("Player %u attempted to eject player %u from non-ejectable seat.", GetPlayer()->GetGUIDLow(), GUID_LOPART(guid));
             }
             else
                 sLog->outError("Player %u tried to eject player %u from vehicle, but the latter was not found in world!", GetPlayer()->GetGUIDLow(), GUID_LOPART(guid));
@@ -650,6 +660,8 @@ void WorldSession::HandleEjectPassenger(WorldPacket &data)
                     unit->ExitVehicle();
                     unit->ToCreature()->ForcedDespawn(1000);
                 }
+                else
+                    sLog->outError("Player %u attempted to eject creature GUID "UI64FMTD" from non-ejectable seat.", GetPlayer()->GetGUIDLow(), GUID_LOPART(guid));
             }
             else
                 sLog->outError("Player %u tried to eject creature guid %u from vehicle, but the latter was not found in world!", GetPlayer()->GetGUIDLow(), GUID_LOPART(guid));