public static function is_root($domain)
{
$tlds = Whois::get_tlds();
$domainArr = explode('.', $domain);
$count = count($domainArr);
if ($count < 2 || $count > 3) {
return false;
} elseif ($count == 2) {
return true;
} else {
// 2-th zone domain
if (strlen($domainArr[1]) > 4) {
return false;
} elseif (!in_array($domainArr[1] . '.' . $domainArr[2], $tlds) && !in_array($domainArr[1], array('us', 'com', 'ru', 'info', 'biz', 'org', 'net'))) {
echo $domainArr[1] . '.' . $domainArr[2] . "<br />";
return false;
} else {
return true;
}
}
}