prepare("SELECT id FROM fiat_orders WHERE user_id = ? AND status IN ('matching', 'matched', 'submitting') ORDER BY id DESC LIMIT 1");
$stmt->execute([$_SESSION['user_id']]);
if ($stmt->fetch()) { header("Location: chat.php"); exit; }
$fiat_rates = get_fiat_rates();
$fiat_currencies_info = [
'USD' => 'US Dollar', 'EUR' => 'Euro', 'GBP' => 'British Pound', 'CNY' => 'Chinese Yuan', 'HKD' => 'Hong Kong Dollar', 'JPY' => 'Japanese Yen', 'KRW' => 'Korean Won', 'SGD' => 'Singapore Dollar', 'TWD' => 'Taiwan Dollar', 'THB' => 'Thai Baht', 'VND' => 'Vietnamese Dong', 'IDR' => 'Indonesian Rupiah', 'MYR' => 'Malaysian Ringgit',
];
?>