[Draft] Integrate the PlatformAudio to unity

Runtime/Plugins/iOS/LiveKitAudioSession.mm

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2024 LiveKit, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#import <AVFoundation/AVFoundation.h>
+
+extern "C" {
+
+/// Configures the iOS audio session for VoIP/WebRTC use.
+/// This sets AVAudioSessionCategoryPlayAndRecord with VoiceChat mode,
+/// which enables the VPIO (Voice Processing IO) AudioUnit for:
+/// - Hardware echo cancellation (AEC)
+/// - Automatic gain control (AGC)
+/// - Noise suppression (NS)
+///
+/// Call this before creating PlatformAudio to ensure WebRTC can
+/// properly initialize the microphone and speaker.
+void LiveKit_ConfigureAudioSessionForVoIP() {
+    AVAudioSession* session = [AVAudioSession sharedInstance];
+    NSError* error = nil;
+
+    // Configure for VoIP with echo cancellation
+    BOOL success = [session setCategory:AVAudioSessionCategoryPlayAndRecord
+                                   mode:AVAudioSessionModeVoiceChat
+                                options:AVAudioSessionCategoryOptionDefaultToSpeaker |
+                                        AVAudioSessionCategoryOptionAllowBluetooth |
+                                        AVAudioSessionCategoryOptionAllowBluetoothA2DP
+                                  error:&error];
+
+    if (!success || error) {
+        NSLog(@"LiveKit: Failed to configure VoIP audio session: %@", error.localizedDescription);
+        return;
+    }
+
+    // Activate the audio session
+    success = [session setActive:YES error:&error];
+    if (!success || error) {
+        NSLog(@"LiveKit: Failed to activate audio session: %@", error.localizedDescription);
+        return;
+    }
+
+    NSLog(@"LiveKit: Audio session configured for VoIP (PlayAndRecord + VoiceChat mode)");
+}
+
+/// Restores the audio session to the default ambient category.
+/// Call this when PlatformAudio is disposed if you want to restore
+/// the original audio behavior.
+void LiveKit_RestoreDefaultAudioSession() {
+    AVAudioSession* session = [AVAudioSession sharedInstance];
+    NSError* error = nil;
+
+    [session setCategory:AVAudioSessionCategoryAmbient error:&error];
+    if (error) {
+        NSLog(@"LiveKit: Failed to restore default audio session: %@", error.localizedDescription);
+    }
+}
+
+}

Runtime/Scripts/Internal/FFIClients/FfiRequestExtensions.cs

@@ -149,6 +149,19 @@ public static void Inject<T>(this FfiRequest ffiRequest, T request)
                 case RemixAndResampleRequest remixAndResampleRequest:
                     ffiRequest.RemixAndResample = remixAndResampleRequest;
                     break;
+                // PlatformAudio
+                case NewPlatformAudioRequest newPlatformAudioRequest:
+                    ffiRequest.NewPlatformAudio = newPlatformAudioRequest;
+                    break;
+                case GetAudioDevicesRequest getAudioDevicesRequest:
+                    ffiRequest.GetAudioDevices = getAudioDevicesRequest;
+                    break;
+                case SetRecordingDeviceRequest setRecordingDeviceRequest:
+                    ffiRequest.SetRecordingDevice = setRecordingDeviceRequest;
+                    break;
+                case SetPlayoutDeviceRequest setPlayoutDeviceRequest:
+                    ffiRequest.SetPlayoutDevice = setPlayoutDeviceRequest;
+                    break;
                 case LocalTrackMuteRequest localTrackMuteRequest:
                     ffiRequest.LocalTrackMute = localTrackMuteRequest;
                     break;