Парсинг и замена номеров телефонов

$string = file_get_contents('./index.html', FILE_USE_INCLUDE_PATH);
$pattern = '/[0-9]{2}\s\S[0-9]{2}\S\s[0-9]{1,3}\S[0-9]{2,4}\S[0-9]{2}/';
$raw = preg_match($pattern, $string, $raw);
    
$filter_pattern = '/\d/';
$replacement = "";
$filter = preg_replace($filter_pattern, $replacement, $raw);
    
$mytel = "80961231212";
$newtel_pattern = '/\D/';
$newtel_replacement = $mytel;
$newtel = preg_replace($newtel_pattern, $newtel_replacement, $filter);
 
header("Location: http://www.xxxxxx.com.ua/index.html");

$raw = [B]preg_match_all[/B]($pattern, $string, $raw);
$filter_pattern = '/\d/';
$replacement = "";
$filter = preg_replace($filter_pattern, $replacement, [B]$raw[0][/B]);

/[0-9]{2}[\s][\S][0-9]{2}[\S][\s][0-9][-0-9][0-9][-0-9][0-9]{2}[-][0-9]{2}/

$string = file_get_contents('http://www.xxxxxxx.com.ua/index.html', FILE_USE_INCLUDE_PATH);
$pattern = '/\d{2}\s\S\d{2}\S\s[\d \S]{9}/';
$out = preg_replace($pattern, '80 (12) 123-12-12', $string);
header("Location: http://www.xxxxxxx.com.ua/index.html");

$string = file_get_contents('./index.html', NULL, NULL);
$pattern = '/\d{2}\s\S\d{2}\S\s[\d \S]{9}/';
$string = preg_replace($pattern, '80 (12) 123-12-12', $string);
file_put_contents('index.html', $string);
header("Location: http://www.xxxxxx.com.ua/index.html");