Make RtpSender.getCapabilities static (#154)

Co-authored-by: evdokimovs <evdokimovs@protonmail.ch>

example/integration_test/webrtc_test.dart

@@ -237,11 +237,7 @@ void main() {
 
   testWidgets('Get capabilities', (WidgetTester tester) async {
     if (!Platform.isAndroid && !Platform.isIOS) {
-      var pc = await PeerConnection.create(IceTransportType.all, []);
-      var t1 = await pc.addTransceiver(
-          MediaKind.video, RtpTransceiverInit(TransceiverDirection.sendRecv));
-
-      var capabilities = await t1.sender.getCapabilities(MediaKind.video);
+      var capabilities = await RtpSender.getCapabilities(MediaKind.video);
 
       expect(
           capabilities.codecs
@@ -267,28 +263,43 @@ void main() {
   });
 
   testWidgets('SetCodecPreferences', (WidgetTester tester) async {
-    var pc = await PeerConnection.create(IceTransportType.all, []);
-    var vtrans = await pc.addTransceiver(
+    var pc1 = await PeerConnection.create(IceTransportType.all, []);
+    var pc2 = await PeerConnection.create(IceTransportType.all, []);
+
+    var vtrans = await pc1.addTransceiver(
         MediaKind.video, RtpTransceiverInit(TransceiverDirection.sendRecv));
 
-    var capabilities = await vtrans.sender.getCapabilities(MediaKind.video);
+    var capabilities = await RtpSender.getCapabilities(MediaKind.video);
 
     var names = capabilities.codecs.map((c) => c.name).toList();
     expect(names.contains("VP9"), isTrue);
     expect(names.contains("VP8"), isTrue);
 
-    var h264Preferences = capabilities.codecs.where((element) {
+    var vp8Preferences = capabilities.codecs.where((element) {
       return element.name == 'VP8';
     }).toList();
 
-    await vtrans.setCodecPreferences(h264Preferences);
+    await vtrans.setCodecPreferences(vp8Preferences);
 
-    var offer = await pc.createOffer();
+    var offer = await pc1.createOffer();
 
     expect(offer.description.contains("VP8"), isTrue);
     expect(offer.description.contains("H264"), isFalse);
     expect(offer.description.contains("VP9"), isFalse);
     expect(offer.description.contains("AV1"), isFalse);
+
+    await pc2.setRemoteDescription(offer);
+
+    var answer = await pc2.createAnswer();
+
+    expect(answer.description.contains("VP8"), isTrue);
+    expect(answer.description.contains("H264"), isFalse);
+    expect(answer.description.contains("VP9"), isFalse);
+    expect(answer.description.contains("AV1"), isFalse);
+
+    await pc1.close();
+    await pc2.close();
+    await vtrans.dispose();
   });
 
   testWidgets('Get transceivers', (WidgetTester tester) async {

lib/medea_flutter_webrtc.dart

@@ -8,6 +8,7 @@ export 'src/api/transceiver.dart' if (dart.library.html) 'none.dart';
 export 'src/api/parameters.dart' if (dart.library.html) 'none.dart';
 export 'src/api/send_encoding_parameters.dart'
     if (dart.library.html) 'none.dart';
+export 'src/model/capability.dart' if (dart.library.html) 'none.dart';
 export 'src/model/constraints.dart' if (dart.library.html) 'none.dart';
 export 'src/model/constraints.dart' show FacingMode;
 export 'src/model/device.dart' if (dart.library.html) 'none.dart';

lib/src/api/sender.dart

@@ -46,11 +46,24 @@ abstract class RtpSender {
   Future<void> setParameters(RtpParameters parameters);
 
   /// [RtpCapabilities] of an RTP sender of the specified [MediaKind].
-  Future<RtpCapabilities> getCapabilities(MediaKind kind);
+  static Future<RtpCapabilities> getCapabilities(MediaKind kind) {
+    if (isDesktop) {
+      return _RtpSenderFFI.getCapabilities(kind);
+    } else {
+      return _RtpSenderChannel.getCapabilities(kind);
+    }
+  }
 }
 
 /// [MethodChannel]-based implementation of a [RtpSender].
 class _RtpSenderChannel extends RtpSender {
+  /// [RtpCapabilities] of an RTP sender of the specified [MediaKind].
+  static Future<RtpCapabilities> getCapabilities(MediaKind kind) async {
+    var map = await _peerConnectionFactoryMethodChannel
+        .invokeMethod('getRtpSenderCapabilities', {'kind': kind.index});
+    return RtpCapabilities.fromMap(map);
+  }
+
   /// Creates an [RtpSender] basing on the [Map] received from the native side.
   _RtpSenderChannel.fromMap(dynamic map) {
     _chan = methodChannel('RtpSender', map['channelId']);
@@ -81,17 +94,16 @@ class _RtpSenderChannel extends RtpSender {
   Future<void> setParameters(RtpParameters parameters) async {
     await _chan.invokeListMethod('setParameters', parameters.toMap());
   }
-
-  @override
-  Future<RtpCapabilities> getCapabilities(MediaKind kind) async {
-    var map = await _peerConnectionFactoryMethodChannel
-        .invokeMethod('getRtpSenderCapabilities', {'kind': kind.index});
-    return RtpCapabilities.fromMap(map);
-  }
 }
 
 /// FFI-based implementation of a [RtpSender].
 class _RtpSenderFFI extends RtpSender {
+  /// [RtpCapabilities] of an RTP sender of the specified [MediaKind].
+  static Future<RtpCapabilities> getCapabilities(MediaKind kind) async {
+    return RtpCapabilities.fromFFI(await api!
+        .getRtpSenderCapabilities(kind: ffi.MediaType.values[kind.index]));
+  }
+
   /// Native side peer connection.
   final ffi.ArcPeerConnection _peer;
 
@@ -122,10 +134,4 @@ class _RtpSenderFFI extends RtpSender {
     await api!.senderSetParameters(
         transceiver: _transceiver, params: parameters.toFFI());
   }
-
-  @override
-  Future<RtpCapabilities> getCapabilities(MediaKind kind) async {
-    return RtpCapabilities.fromFFI(await api!
-        .getRtpSenderCapabilities(kind: ffi.MediaType.values[kind.index]));
-  }
 }