if (isset($_POST['submit'])) {
    require_once $_SERVER['DOCUMENT_ROOT']."/config/config.php";
    $username = mysql_real_escape_string($_POST['username']);
    $password = mysql_real_escape_string($_POST['password']);
    if (empty($errors)) {
        $query = "SELECT id, salt FROM users WHERE username = '$username' LIMIT 1";
        $result = mysql_query($query);
        if (mysql_num_rows($result) > 0) {
            $id = mysql_result($result,0,"id");
            $salt = mysql_result($result,0,"salt");
            $password = hash_pass($password.$salt.PASSWORD_SALT);
            $query = "SELECT username, password, lang FROM users WHERE id = '$id' AND password = '$password' LIMIT 1";
            $result = mysql_query($query);
            if (mysql_num_rows($result) > 0) {
                $username = mysql_result($result,0,"username");
                $password = mysql_result($result,0,"password");
                # use first 10 of password as Session key.
                $password = substr($password, 0, 10);
                if ($_POST['remember'] == "1"){
                    setcookie ('key', $password, time() + 2592000);
                    setcookie ('id', $id, time() + 2592000);
                }
                session_start();
                $_SESSION['username'] = $username;
                $_SESSION['id'] = $id;
                $_SESSION['key'] = $password;
                $_SESSION['lang'] = mysql_result($result,0,"lang");
                header("Location: profile");
            } else {
                $errors[] = $incorrect_user_or_pass;
            }
        } else {
            $errors[] = $incorrect_user_or_pass;
        }
    }
}