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