<?php
 
error_reporting(-1);
 
function callCheck($phone) {
	$regexp = '/^(8|\+[0-9]?)[ (-]?[0-9]{3})?( -?[0-9]){7}$/';
	if (preg_match($regexp, $phone)) {
		echo "Все верно\n";
	} else {
		echo "Введите номер телефона в формате 8-(XXX)-XXX-XX-XX\n";
	}
}
$right = "8(911)523-09 50";
$wrong = "Allah velik";
$wrong2 = "8d91105240950";
$test1 = callCheck($right);
$test2 = callCheck($wrong);
$test3 = callCheck($wrong2);

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