PHP website script to send an email notification about the changed .php files in the last 24 hours

checkfiles.php

<?php
/**
 * @package    CheckChangedFiles
 *
 * @copyright  Copyright (C) 2021 db8.nl. All rights reserved.
 * @license    GNU General Public License version 2 or later; see LICENSE.txt
 */

/**
 * A script to check new files and mail them to an e-mail address
 * When the server does not support the mail functionality on SSH CLI command line
 * Put the script at some folder and give it an unique not-easy-to-guess name checkfiles-324586yasfdasf234.php
 * and trigger it via the URL via a crontab
 */

use Joomla\CMS\Factory;

define('_JEXEC', 1);
define('JPATH_BASE', dirname(__FILE__));

require_once JPATH_BASE . '/includes/defines.php';
require_once JPATH_BASE . '/includes/framework.php';

$mainframe = JFactory::getApplication('site');
$mainframe->initialise();

// Settings
$folder     = '/var/www/public_html/';
$subject    = '[example.com] Files changed on server';
$recipients = [
	'person1@example.com',
	'person2@example.com'
];
$body       = "The following files have been changed in the last 24 hours:\n\n";

$files      = scanSite($folder, "/^.*\.(php)$/");

foreach ($files as $key => $file)
{
	$body .= $key + 1 . '. ' . $file . "\n";
}

mailChanges($subject, $recipients, $body);

/**
 * @param   string  $folder   Folder to scan
 * @param   string  $pattern  File pattern to scan
 *
 * @return array
 * @since 1.0.0
 */
function scanSite($folder, $pattern)
{
	$dir      = new RecursiveDirectoryIterator($folder);
	$ite      = new RecursiveIteratorIterator($dir);
	$files    = new RegexIterator($ite, $pattern, RegexIterator::GET_MATCH);
	$fileList = array();

	foreach ($files as $file)
	{
		if (filemtime($file[0]) > (time() - (24 * 60 * 60)))
		{
			$fileList[] = $file[0];
		}
	}

	return $fileList;
}

/**
 * @param   string  $subject     Email subject
 * @param   array   $recipients  Send email to these recepients
 * @param   string  $body        Email body
 *
 * @return  void
 * @since   1.0.0
 */
function mailChanges($subject, $recipients, $body)
{
	$mailer = Factory::getMailer();
	$config = Factory::getConfig();
	$sender = [
		$config->get('mailfrom'),
		$config->get('fromname')
	];

	$mailer->setSender($sender);
	$mailer->addRecipient($recipients);
	$mailer->setSubject($subject);
	$mailer->setBody($body);

	$send = $mailer->Send();

	if ($send !== true)
	{
		echo 'Error sending email: ';
	}
	else
	{
		echo 'Mail sent';
	}
}