DragonBe\Vies\Validator\ValidatorPT::validate PHP Method

    public function validate($vatNumber)
    {
        if (strlen($vatNumber) != 9) {
            return false;
        }
        $checksum = (int) $vatNumber[8];
        $weights = array(9, 8, 7, 6, 5, 4, 3, 2);
        $checkval = $this->sumWeights($weights, $vatNumber);
        $checkval = 11 - $checkval % 11 > 9 ? 0 : 11 - $checkval % 11;
        if ($checksum != $checkval) {
            return false;
        }
        return true;
    }