public static function setItalianLeadingZerosForPhoneNumber($nationalNumber, PhoneNumber $phoneNumber)
{
if (strlen($nationalNumber) > 1 && substr($nationalNumber, 0, 1) == '0') {
$phoneNumber->setItalianLeadingZero(true);
$numberOfLeadingZeros = 1;
// Note that if the national number is all "0"s, the last "0" is not counted as a leading
// zero.
while ($numberOfLeadingZeros < strlen($nationalNumber) - 1 && substr($nationalNumber, $numberOfLeadingZeros, 1) == '0') {
$numberOfLeadingZeros++;
}
if ($numberOfLeadingZeros != 1) {
$phoneNumber->setNumberOfLeadingZeros($numberOfLeadingZeros);
}
}
}