Generate Steam DeviceID by SteamID for accepting mobile confirmations

getSteamDeviceID.php

<?php
/**
 * Generate device id by steamid
 * Usage: getDeviceID('steamid');
 *
 * @param string $steamid SHOULD BE STRING 
 * @return string
 */
function getDeviceID($steamid) {
    $sha1 = sha1($steamid);
    $cut = substr($sha1, 0, 32);
    $deviceID = preg_replace('/^([0-9a-f]{8})([0-9a-f]{4})([0-9a-f]{4})([0-9a-f]{4})([0-9a-f]{12}).*$/', '$1-$2-$3-$4-$5', $cut);

    $prepend = 'android:';

    return $prepend . $deviceID;
}