isLoggedIn()) { header('Location: index.php'); exit; } $errors = []; if ($_SERVER['REQUEST_METHOD'] === 'POST') { $username = trim($_POST['username'] ?? ''); $password = $_POST['password'] ?? ''; if (empty($username) || empty($password)) { $errors[] = t('admin_login_error_empty'); } elseif ($auth->login($username, $password)) { header('Location: index.php'); exit; } else { $errors[] = t('admin_login_error_invalid'); } } ?>