Add name prefix filtering (#45)

* Add name filter

* Change name filter to "prefix"

* Implement namePrefix filtering

* Update lib/src/universal_ble_platform_interface.dart

* Update lib/src/universal_ble_platform_interface.dart

---------

Co-authored-by: fotidim <foti@navideck.com>

lib/src/models/scan_filter.dart

@@ -3,10 +3,12 @@ import 'dart:typed_data';
 class ScanFilter {
   final List<String> withServices;
   final List<ManufacturerDataFilter> withManufacturerData;
+  final List<String> withNamePrefix;
 
   ScanFilter({
     this.withServices = const [],
     this.withManufacturerData = const [],
+    this.withNamePrefix = const [],
   });
 }
 

lib/src/universal_ble_linux/universal_ble_linux.dart

@@ -57,6 +57,7 @@ class UniversalBleLinux extends UniversalBlePlatform {
     ScanFilter? scanFilter,
   }) async {
     await _ensureInitialized();
+    await super.startScan(scanFilter: scanFilter);
     if (_activeAdapter?.discovering != true) {
       // Add services filter
       _activeAdapter?.setDiscoveryFilter(
@@ -399,7 +400,7 @@ class UniversalBleLinux extends UniversalBlePlatform {
     }
 
     // Update scan results only if rssi is available
-    if (device.rssi != 0) onScanResult?.call(device.toBleScanResult());
+    if (device.rssi != 0) updateScanResult(device.toBleScanResult());
 
     // Setup Cache
     _devices[device.address] = device;
@@ -414,7 +415,7 @@ class UniversalBleLinux extends UniversalBlePlatform {
       for (final property in properties) {
         switch (property) {
           case BluezProperty.rssi:
-            onScanResult?.call(device.toBleScanResult());
+            updateScanResult(device.toBleScanResult());
             break;
           case BluezProperty.connected:
             onConnectionChanged?.call(
@@ -425,7 +426,7 @@ class UniversalBleLinux extends UniversalBlePlatform {
             );
             break;
           case BluezProperty.manufacturerData:
-            onScanResult?.call(device.toBleScanResult());
+            updateScanResult(device.toBleScanResult());
             break;
           case BluezProperty.paired:
             onPairingStateChange?.call(device.address, device.paired, null);

lib/src/universal_ble_pigeon/universal_ble_pigeon_channel.dart

@@ -31,6 +31,7 @@ class UniversalBlePigeonChannel extends UniversalBlePlatform {
   Future<void> startScan({
     ScanFilter? scanFilter,
   }) async {
+    await super.startScan(scanFilter: scanFilter);
     await _channel.startScan(
       scanFilter.toUniversalScanFilter(),
     );
@@ -116,7 +117,7 @@ class UniversalBlePigeonChannel extends UniversalBlePlatform {
   /// To set listeners
   void _setupListeners() {
     UniversalBleCallbackChannel.setUp(_UniversalBleCallbackHandler(
-      scanResult: (BleScanResult scanResult) => onScanResult?.call(scanResult),
+      scanResult: (BleScanResult scanResult) => updateScanResult(scanResult),
       availabilityChange: (AvailabilityState state) =>
           onAvailabilityChange?.call(state),
       connectionChanged: (String deviceId, BleConnectionState state) =>

lib/src/universal_ble_platform_interface.dart

@@ -3,13 +3,17 @@ import 'dart:typed_data';
 import 'package:universal_ble/universal_ble.dart';
 
 abstract class UniversalBlePlatform {
+  ScanFilter? _scanFilter;
+
   Future<AvailabilityState> getBluetoothAvailabilityState();
 
   Future<bool> enableBluetooth();
 
   Future<void> startScan({
     ScanFilter? scanFilter,
-  });
+  }) async {
+    _scanFilter = scanFilter;
+  }
 
   Future<void> stopScan();
 
@@ -44,6 +48,17 @@ abstract class UniversalBlePlatform {
     List<String>? withServices,
   );
 
+  void updateScanResult(BleScanResult scanResult) {
+    // Filter by name
+    ScanFilter? scanFilter = _scanFilter;
+    if (scanFilter != null && scanFilter.withNamePrefix.isNotEmpty) {
+      if (scanResult.name == null ||
+          !scanFilter.withNamePrefix
+              .any((e) => scanResult.name?.startsWith(e) == true)) return;
+    }
+    onScanResult?.call(scanResult);
+  }
+
   OnAvailabilityChange? onAvailabilityChange;
   OnScanResult? onScanResult;
   OnConnectionChanged? onConnectionChanged;

lib/src/universal_ble_web/universal_ble_web.dart

@@ -127,7 +127,7 @@ class UniversalBleWeb extends UniversalBlePlatform {
     _bluetoothDeviceList[device.id] = device;
 
     // Update Scan Result
-    onScanResult?.call(device.toBleScanResult());
+    updateScanResult(device.toBleScanResult());
 
     /// This will work only if `chrome://flags/#enable-experimental-web-platform-features` is enabled
     if (FlutterWebBluetooth.instance.hasRequestLEScan) {
@@ -140,7 +140,7 @@ class UniversalBleWeb extends UniversalBlePlatform {
 
         _deviceAdvertisementStreamList[device.id] =
             device.advertisements.listen((event) {
-          onScanResult?.call(
+          updateScanResult(
             device.toBleScanResult(
               rssi: event.rssi,
               manufacturerDataMap: event.manufacturerData,
@@ -410,6 +410,13 @@ extension ScanFilterExtension on ScanFilter {
       );
     }
 
+    // Add name filter
+    for (var name in withNamePrefix) {
+      filters.add(
+        RequestFilterBuilder(namePrefix: name),
+      );
+    }
+
     if (filters.isEmpty) {
       return RequestOptionsBuilder.acceptAllDevices();
     }