private void InteractWithItemObject(ItemObject itemObject)
        {
            Debug.Assert(itemObject.Item != null);
            IUsable     usable     = itemObject.Item as IUsable;
            IPickupable pickupable = itemObject.Item as IPickupable;
            IEquipable  equipable  = itemObject.Item as IEquipable;
            IStackable  stackable  = itemObject.Item as IStackable;

            if (usable != null)
            {
                usable.OnUse(_stats, itemObject);
            }
            else if (pickupable != null)
            {
                if (equipable != null && equipable.IsDurable && _equipment.EquipmentTable[equipable.EquipmentType].IsEmpty)
                {
                    equipable.OnEquip(_equipment, _stats);
                }
                else if (stackable != null)
                {
                    stackable.OnStack(_inventory);
                }
                else
                {
                    pickupable.OnPutInInventory(_inventory);
                }
                pickupable.OnRemoveFromGround(itemObject);
            }
        }
        private void ReturnAirItem(object[] eventParams)
        {
            if (_airItem.IsEmpty)
            {
                return;
            }

            SlotPosition originalPosition = _airItem.OriginalPosition;
            Item         itemAir          = _airItem.Item;
            IPickupable  pickupableAir    = itemAir as IPickupable;
            IEquipable   equipableAir     = itemAir as IEquipable;
            IStackable   stackableAir     = itemAir as IStackable;

            pickupableAir.OnRemoveFromAir(_airItem);

            if (originalPosition.RowIndex == EquipmentSlot.EQUIPMENT_SLOT_ROW_INDEX)
            {
                Equipment.EquipmentType equipmentType = (Equipment.EquipmentType)originalPosition.SlotIndex;

                if (_equipment.EquipmentTable[equipmentType].IsEmpty)
                {
                    equipableAir.OnEquip(_equipment, _stats);
                }
                else
                {
                    pickupableAir.OnPutInInventory(_inventory);
                }
            }
            else
            {
                if (stackableAir != null)
                {
                    stackableAir.OnStack(_inventory, originalPosition);
                }
                else if (_inventory.IsItemEmpty(originalPosition))
                {
                    pickupableAir.OnPutInInventory(_inventory, originalPosition);
                }
                else
                {
                    pickupableAir.OnPutInInventory(_inventory);
                }
            }
        }