public function updateItem($itemHash, $key, $value)
    {
        if (empty($item = $this->getItem($itemHash)) === false) {
            if ($key == 'qty' && $value == 0) {
                return $this->removeItem($itemHash);
            }

            $item->$key = $value;
        }

        $this->update();

        return $item;
    }