Cümledeki En Uzun Kelimeyi Bulma

<?php
setlocale(LC_ALL, "TURKISH");
header('Content-Type: text/html; charset=utf-8');
mb_language('uni'); 
mb_internal_encoding('UTF-8');
class kelimeSay{
    private $metin;
    function __construct(){
        $this->metin = "Nothing Supplied"; 
    }
    function enUzun($metin){
      try{
            if(empty($metin)){
                throw new Exception("$this->metin");
            }
            $this->metin = $metin;
            $metin=str_replace(array(".",",","?","!",":",";"),"",$metin);
            $say = array_filter(explode(" ",$metin));
            $kontrol=0;
            foreach($say as $s){
                $s=str_replace(" ","",$s);
                if(mb_strlen($s) > $kontrol){
                    $kontrol =mb_strlen($s);
                    $kelime =$s;
                }
            }
            return array("harf"=>$kontrol,$kelime);
        } 
        catch(Exception $e){
            echo 'Caught exception: ',  $e->getMessage(), "\n";
        }
    }
}
$metin = "Korkma sönmez bu şafaklarda yüzen al sancak.";
$obj = new kelimeSay;
print_r($obj->enUzun($metin));
?>
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Array ( [harf] => 10 [0] => şafaklarda )
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