(PHP) Update jQuery Latest Version (Local File)

<?php
// -------------------------------------------------------------

header('Content-Type: text/html; charset=utf-8');

// -------------------------------------------------------------


$time_stamp = time();
$cache_time = (3600*24*3);

$source_url = 'http://code.jquery.com/jquery-latest.min.js';
$local_file = 'jquery-latest.min.js';


// -------------------------------------------------------------

function update_jquery($source_url, $local_file, $cache_time, $time_stamp) {

    $vstatus = false;

    $last_update = @filemtime($local_file);

    if (!$last_update || ($cache_time < ($time_stamp - $last_update))) {

    if (!file_exists($local_file)) {
        copy($source_url,$local_file);
        $vstatus = 'new';
    }
    else {
        $pattern = "@\!\s(.*?)\s\|@";

        $loc = file_get_contents($local_file);
        preg_match($pattern,$loc,$mloc);

        $ext = file_get_contents($source_url);
        preg_match($pattern,$ext,$mext);

        if ($mloc[1] == $mext[1]) {
            touch($local_file,$time_stamp);
            $vstatus = 'no_change';
        }
        else {
            copy($source_url,$local_file);
            $vstatus = 'update';
        }

    }

    }
    else {
    $vstatus = 'cached';
    }

    return $vstatus;

}

// -------------------------------------------------------------


$jver_status = update_jquery($source_url, $local_file, $cache_time, $time_stamp);


// -------------------------------------------------------------


print "<p>Update Status: ".$jver_status."</p>\n";


// -------------------------------------------------------------
?>