bug Security Arbitrary URL Redirection detected (FIX)

<?php

class Tools extends ToolsCore
{

    public static function redirect($url, $base_uri = __PS_BASE_URI__, Link $link = null, $headers = null)
    {
        if (!$link)
            $link = Context::getContext()->link;

        //exit();
        if(self::isValidUrl($url))
            if(self::isExternalUrl($url))
                $url="/index.php";
        if (strpos($url, 'http://') === false && strpos($url, 'https://') === false && $link)
        {
            if (strpos($url, $base_uri) === 0)
                $url = substr($url, strlen($base_uri));
            if (strpos($url, 'index.php?controller=') !== false && strpos($url, 'index.php/') == 0)
            {
                $url = substr($url, strlen('index.php?controller='));
                if (Configuration::get('PS_REWRITING_SETTINGS'))
                    $url = Tools::strReplaceFirst('&', '?', $url);
            }

            $explode = explode('?', $url);
            // don't use ssl if url is home page
            // used when logout for example
            $use_ssl = !empty($url);
            $url = $link->getPageLink($explode[0], $use_ssl);
            if (isset($explode[1]))
                $url .= '?'.$explode[1];
        }

        // Send additional headers
        if ($headers)
        {
            if (!is_array($headers))
                $headers = array($headers);

            foreach ($headers as $header)
                header($header);
        }

        header('Location: '.$url);
        exit;
    }
    public static function redirectAdmin($url)
    {
      if(self::isValidUrl($url))
        if(self::isExternalUrl($url))
            $url="/index.php";
        header('Location: '.$url);
        exit;
    }

    public static function isExternalUrl($url=null)
    {
        $url=parse_url($url);
        $url=$url['host'];
       if(!is_null($url))
            if(strtolower($_SERVER['SERVER_NAME'])!=strtolower($url))
                return TRUE;
        return FALSE;


    }
    public static function  isValidUrl($url){
        if(!$url || !is_string($url))
            return false;
         if(!preg_match('%^((https?://)|(www\.))([a-z0-9-].?)+(:[0-9]+)?(/.*)?$%i', $url))
                        return false;
        return true;
    }



}