<?php

error_reporting(-1);

$correctNumbers = [ 
  '84951234567',  '+74951234567', '8-495-1-234-567', 
  '8 (8122) 56-56-56', '8-911-1234567', '8 (911) 12 345 67', 
  '8-911 12 345 67', '8 (911) - 123 - 45 - 67', '+ 7 999 123 4567', 
  '8 ( 999 ) 1234567', '8 999 123 4567'
];

$incorrectNumbers = [
  '02', '84951234567 позвать люсю', '849512345', '849512345678', 
  '8 (409) 123-123-123', '7900123467', '5005005001', '8888-8888-88',
  '84951a234567', '8495123456a', 
  '+1 234 5678901', /* неверный код страны */
  '+8 234 5678901', /* либо 8 либо +7 */
  '7 234 5678901' /* нет + */
];

$allNumbers = [$correctNumbers, $incorrectNumbers];
$pattern = "/^(8|\\+\\s?7)([\\s\\(-]*\\d[\\s\\)-]*){10}$/";
$patterns = ["/^(8|\\+\\s?7)/", "/[\\s\\(\\)-]/"];
$replaces = ["8", ""];

foreach ($allNumbers as $oneOflists) {
	foreach ($oneOflists as $number) {
		if (preg_match($pattern, $number)) {
          echo "Номер '{$number}' введен верно! ";
          $number = preg_replace($patterns, $replaces, $number);
          echo "Форм.: {$number}\n";
		} else {
          echo "Номер '{$number}' введен неверно!\n";
		}
	}
}