/**
* Strips any national prefix (such as 0, 1) present in the number provided.
*
* @param string $number the normalized telephone number that we wish to strip any national
* dialing prefix from
* @param PhoneMetadata $metadata the metadata for the region that we think this number is from
* @param string $carrierCode a place to insert the carrier code if one is extracted
* @return bool true if a national prefix or carrier code (or both) could be extracted.
*/
public function maybeStripNationalPrefixAndCarrierCode(&$number, PhoneMetadata $metadata, &$carrierCode)
{
$numberLength = mb_strlen($number);
$possibleNationalPrefix = $metadata->getNationalPrefixForParsing();
if ($numberLength == 0 || $possibleNationalPrefix === null || mb_strlen($possibleNationalPrefix) == 0) {
// Early return for numbers of zero length.
return false;
}
// Attempt to parse the first digits as a national prefix.
$prefixMatcher = new Matcher($possibleNationalPrefix, $number);
if ($prefixMatcher->lookingAt()) {
$nationalNumberRule = $metadata->getGeneralDesc()->getNationalNumberPattern();
// Check if the original number is viable.
$nationalNumberRuleMatcher = new Matcher($nationalNumberRule, $number);
$isViableOriginalNumber = $nationalNumberRuleMatcher->matches();
// $prefixMatcher->group($numOfGroups) === null implies nothing was captured by the capturing
// groups in $possibleNationalPrefix; therefore, no transformation is necessary, and we just
// remove the national prefix
$numOfGroups = $prefixMatcher->groupCount();
$transformRule = $metadata->getNationalPrefixTransformRule();
if ($transformRule === null || mb_strlen($transformRule) == 0 || $prefixMatcher->group($numOfGroups - 1) === null) {
// If the original number was viable, and the resultant number is not, we return.
$matcher = new Matcher($nationalNumberRule, substr($number, $prefixMatcher->end()));
if ($isViableOriginalNumber && !$matcher->matches()) {
return false;
}
if ($carrierCode !== null && $numOfGroups > 0 && $prefixMatcher->group($numOfGroups) !== null) {
$carrierCode .= $prefixMatcher->group(1);
}
$number = substr($number, $prefixMatcher->end());
return true;
} else {
// Check that the resultant number is still viable. If not, return. Check this by copying
// the string and making the transformation on the copy first.
$transformedNumber = $number;
$transformedNumber = substr_replace($transformedNumber, $prefixMatcher->replaceFirst($transformRule), 0, $numberLength);
$matcher = new Matcher($nationalNumberRule, $transformedNumber);
if ($isViableOriginalNumber && !$matcher->matches()) {
return false;
}
if ($carrierCode !== null && $numOfGroups > 1) {
$carrierCode .= $prefixMatcher->group(1);
}
$number = substr_replace($number, $transformedNumber, 0, mb_strlen($number));
return true;
}
}
return false;
}
