DragonBe\Vies\Validator\ValidatorLT::validateLegal PHP Method

    private function validateLegal($vatNumber)
    {
        if ($vatNumber[7] != 1) {
            return false;
        }
        $weights = array(1, 2, 3, 4, 5, 6, 7, 8);
        $checksum = (int) $vatNumber[8];
        $checkval = $this->sumWeights($weights, $vatNumber);
        if ($checkval % 11 == 10) {
            $weights = array(3, 4, 5, 6, 7, 8, 9, 1);
            $checkval = $this->sumWeights($weights, $vatNumber);
            $checkval = $checkval % 11 == 10 ? 0 : $checkval % 11;
            return $checkval == $checksum ? true : false;
        } else {
            return $checkval % 11 == $checksum ? true : false;
        }
    }