function require_login() {
    if (!isset($_SESSION['user_id']) || empty($_SESSION['user_id'])) {
        header('Location: login.php');
        exit;
    }
}

function get_user_active_packages($user_id) {
    global $conn;

    $sql = "SELECT up.*, p.name as package_name, p.daily_percentage, p.direct_commission
            FROM user_packages up
            JOIN packages p ON up.package_id = p.id
            WHERE up.user_id = ? AND up.status = 'active'
            ORDER BY up.start_date DESC";
    $stmt = $conn->prepare($sql);
    $stmt->bind_param("i", $user_id);
    $stmt->execute();
    $result = $stmt->get_result();

    $packages = [];
    while ($row = $result->fetch_assoc()) {
        $packages[] = $row;
    }

    return $packages;
}