void World::changeQuality(ScriptItem item, short int amount) {
    short int tmpQuality = ((amount+item.getDurability())<100) ? (amount + item.getQuality()) : (item.getQuality() - item.getDurability() + 99);

    if (tmpQuality%100 > 0) {
        item.setQuality(tmpQuality);
        changeItem(item);
    } else {
        erase(item, item.getNumber());
    }
}