// ==================== REFRESH/REPLACE ENDPOINT ====================
if ($uri === '/camera/refresh') {
    header('Content-Type: application/json');
    
    $input_raw = file_get_contents('php://input');
    parse_str($input_raw, $post_data);
    $serialno = $post_data['serialno'] ?? '';
    $c = $post_data['c'] ?? '';
    
    if (empty($serialno)) {
        echo json_encode(['code' => -1, 'expiredTime' => 0]);
        exit;
    }
    
    $conn = new mysqli("localhost", "vcamekma_vc4m_user", "Kohanshin@0542512567890", "vcamekma_vc4m_license");
    if ($conn->connect_error) {
        echo json_encode(['code' => -1, 'expiredTime' => 0]);
        exit;
    }
    
    // Check if device exists and has active expiry
    $stmt = $conn->prepare("SELECT * FROM devices WHERE device_id = ? AND expiry_date > NOW()");
    $stmt->bind_param("s", $serialno);
    $stmt->execute();
    $device = $stmt->get_result()->fetch_assoc();
    
    if (!$device) {
        echo json_encode(['code' => -1, 'expiredTime' => 0]);
        exit;
    }
    
    // Calculate remaining minutes
    $expiry_seconds = strtotime($device['expiry_date']);
    $remain_minutes = max(0, ceil(($expiry_seconds - time()) / 60));
    $now = time();
    
    // Generate tokens (matching xbye.xyz format exactly)
    $rc = base64_encode(random_bytes(96));  // 96 bytes = 128 characters base64
    $otp = base64_encode(random_bytes(96));
    $salt = "**";
    
    // Return exact response matching xbye.xyz
    echo json_encode([
        'code' => 200,
        'allow' => '',
        'rc' => $rc,
        'salt' => $salt,
        'remain' => $remain_minutes,
        'now' => $now,
        'otp' => $otp
    ]);
    exit;
}