Clear camera images older then x seconds

maintenance.php

<?php

echo "maintenance...";

define("ONE_DAY_IN_SECONDS", 86400);

function delete_files_older_than($dir, $fileDateMask, $seconds, $now = NULL) {
    if (is_dir($dir) === false) {
        echo "Dir $dir doesn't exists\n";
        return;
    }
    if (is_null($now)) {
        $now = time();
    }

    echo "Processing dir: $dir\n";
    $dirIterator = new FilesystemIterator($dir);
    foreach ($dirIterator as $fileInfo) {
        if ($fileInfo->isDir()) {
            delete_files_older_than($fileInfo->getPathname(), $fileDateMask, $seconds, $now);
            $subdirIterator = new FilesystemIterator($fileInfo->getRealPath());
            if (!$subdirIterator->valid()) {
                echo "Deleting empty dir:" . $fileInfo->getRealPath() . "\n";
                rmdir($fileInfo->getRealPath());
            }
        } else if ($fileInfo->isFile()) {
            $fileName = $fileInfo->getFilename();
            if (preg_match($fileDateMask, $fileName, $matches)) {
                $fileDate = date_create_from_format('YmdHis', $matches[1]);
                if ($fileDate === false) {
                    continue;
                }
                $fileTimestamp = date_timestamp_get($fileDate);
                $fileAge = $now - $fileTimestamp;
                if ($fileAge >= $seconds) {
                    echo "Will delete file: " . $fileInfo->getFilename() . " age: " . $fileAge . "s\n";
                    unlink($fileInfo->getRealPath());
                } else {
                    echo "Will keep file: " . $fileInfo->getFilename() . " age: " . $fileAge . "s\n";
                }
            }
        }
    }
}

//clearstatcache();
//header("Content-Type: text/plain");

$now = time();
$safeMode = ini_get('safe_mode');
echo "Safe mode: $safeMode\n";
echo "Now timestamp: $now\n";
echo "Max file age: " . ONE_DAY_IN_SECONDS . "s\n";

$dirName = realpath(dirname(__DIR__) . DIRECTORY_SEPARATOR . 'cam');
delete_files_older_than($dirName, '/camera[0-9]*_([0-9]+)\.jpg/', ONE_DAY_IN_SECONDS, $now);
delete_files_older_than($dirName, '/timelapse.webm/', ONE_DAY_IN_SECONDS, $now);