PHP Loginscript für (LDAP) Activedirectory Benutzer

function login_complete ($ldap_server)
{
      if((isset($_COOKIE['cookie_username']) AND ($_COOKIE['cookie_passwort']))) {  
                $username = $_COOKIE['cookie_username'];  
                $passwort = $_COOKIE['cookie_passwort'];  
                $check_positive = 1;
      } else {
               if((isset($_POST['username']) OR ($_POST['passwort']))) {  
                         if(empty($_POST['username']) OR empty($_POST['passwort'])) {  
                                  $array["login_complete"] = "Bitte fuellen Sie alle Felder aus. <br>";  
                         } else {                             
                                  if((isset($_POST['username']) AND ($_POST['passwort']))) {  
                                            $username = $_POST['username'];  
                                            $passwort = $_POST['passwort'];  
                                            $check_positive = 1;
                                  } 
                          }
                } else {
                          $array["login_complete"] = "Sie sind nicht eingeloggt: ";        
                }
      }


      
            if($check_positive==1) {
      //----------------------------------------Login und Bind----------------------------------------      
      if (!($connect=@ldap_connect($ldap_server))) {
            $array["login_complete"] = "Could not connect to ldap server<br>";  
      } else {
      }
      
      // Needed for W2003 AD..
      ldap_set_option($connect, LDAP_OPT_PROTOCOL_VERSION, 3);
      ldap_set_option($connect, LDAP_OPT_REFERRALS, 0);
      
      if (!($bind=@ldap_bind($connect, $username, $passwort))) {
            $array["login_complete"] = "Login oder Passwort falsch. <br>";  
      } else {
            setcookie("cookie_passwort", $passwort, time()+(60*60));  
            setcookie("cookie_username", $username, time()+(60*60));  
            $array["login_check"] = true;  
      }         
}
            $array["username"] = $username;  
            $array["passwort"] = $passwort;  
            $array["connect"] = $connect;  
            return $array;
}      

include "variables.php";  
include "functions.php";  

$login = login_complete ($ldap_server);
$login_complete = $login["login_complete"];  
$username = $login["username"];  
$passwort = $login["passwort"];  
$login_check = $login["login_check"];  
$connect = $login["connect"];  

echo $login_complete;
if($login_check==true) {
echo "     Sie sind eingeloggt als: ".$username;  
} else {
echo "<form action='$file' method='POST'>";  
echo "Benutzername:<br>";  
echo "<input type='text' value='Benutzername' name='username'><br>";  
echo "Passwort:<br>";  
echo "<input type='password' name='passwort'><br>";  
echo "<input type='submit' value='login' name='submit'<br>";  
}