Twitter Check Followers

<?php
error_reporting(E_ALL);
require_once 'RestApi.php';


// Please replace this with own data, by creating application in dev.twitter.com
// Read-only permissions is enough for app.
$consumerKey = '';
$consumerSecret = '';
$accessToken = '';
$accessTokenSecret = '';

$username = 'XXXXXXXXXXXXXXXXXX';      //!< Twitter screen name for user, whose followers are compared
$email = 'joe@example.com'; 		   //!< Email, where data should be sent 

$twitter = new \TwitterPhp\RestApi($consumerKey,$consumerSecret,$accessToken,$accessTokenSecret);
$user = $twitter->connectAsUser();
$list = $user->get(
	'followers/list',
	array(
		'screen_name' => $username,
		'cursor' => -1,
		'count' => 1000  /* If you have more followers than 1000, increase this number */
	)
);

if ($list == null)
{
	echo "Script execution failed. First check SSL certificate. Then check token and token secret data.";
}


$currentnames = array();
if ($list != null)
{
	foreach($list['users'] as $u)
	{
		$currentnames[] = $u['screen_name'];
	}
}

$file = dirname(__FILE__) . '/previous.php';
if (file_exists($file) == false)
{
	file_put_contents($file, '$oldnames = ' .var_export($currentnames, true) . ';');
}
else
{
	require_once($file);
	$absentnames = array();
	$newnames = array();
	foreach($oldnames as $name)
	{
		if (!in_array($name, $currentnames))
		{
			$absentnames []= $name;
		}
	}
	foreach($currentnames as $name)
	{
		if (!in_array($name, $oldnames))
		{
			$newnames []= $name;
		}
	}
	file_put_contents($file, '<?php' . "\n" . '$oldnames = ' .var_export($currentnames, true) . ';');
	
	if (count($absentnames) || count($newnames))
	{
		$message = "Dear $username,\n";
		if (count($absentnames))
		{
			$message  .= "You have lost followers: \n";
			$message .= implode("\n", $absentnames) . "\n";
		}
		if (count($newnames))
		{
			$message  .= "You have gained followers: \n";
			$message .= implode("\n", $newnames) . "\n";
		}
		mail($email, 'Changes in followers list for ' . $username, $message);
	}	
}