feat(voice): add iOS VAD runtime support

apps/chanora_flutter/ios/Runner/AppDelegate.swift

@@ -5,6 +5,7 @@ import AVFoundation
 @main
 @objc class AppDelegate: FlutterAppDelegate, FlutterImplicitEngineDelegate {
   private var iosAudioLifecycleChannel: FlutterMethodChannel?
+  private var iosPlatformChannel: FlutterMethodChannel?
 
   override func application(
     _ application: UIApplication,
@@ -134,32 +135,12 @@ import AVFoundation
       object: nil
     )
 
-    // Request microphone access on first launch rather than waiting
-    // for the user's first voice-channel join. The latter is
-    // surprising: the user has only tapped "connect to server" and
-    // suddenly iOS pops the permission prompt because joining a
-    // text channel happens to trigger audio engine startup. Asking
-    // up-front matches user expectations for a voice-chat client.
-    //
-    // The request is asynchronous and non-blocking. If the user
-    // denies, voice_join will surface a clearer error later when
-    // the audio engine fails to open the input device. The
-    // permission state is cached by iOS so subsequent launches
-    // skip the prompt.
-    //
-    // Deferred ~1 s so iOS finishes initialising the keyboard /
-    // text-input subsystem before the permission alert appears.
-    // Firing the alert too early steals focus from the not-yet-
-    // ready text-input layer, with the symptom that the first tap
-    // on a TextField does nothing (the second tap works because
-    // by then iOS has caught up). DispatchQueue.main.asyncAfter
-    // keeps everything on the main thread; the permission API
-    // itself must be called there too.
-    DispatchQueue.main.asyncAfter(deadline: .now() + 1.0) {
-      AVAudioSession.sharedInstance().requestRecordPermission { granted in
-        NSLog("chanora_flutter: microphone permission granted=\(granted)")
-      }
-    }
+    NotificationCenter.default.addObserver(
+      self,
+      selector: #selector(handleMediaServicesReset(_:)),
+      name: AVAudioSession.mediaServicesWereResetNotification,
+      object: nil
+    )
 
     return super.application(application, didFinishLaunchingWithOptions: launchOptions)
   }
@@ -182,7 +163,7 @@ import AVFoundation
       // wrong rate, causing pitch + timing artifacts).
       logAudioSessionState(context: "setActive")
       let s = AVAudioSession.sharedInstance()
-      let ins = s.currentRoute.inputs.map { "\($0.portType.rawValue)/\($0.portName)" }.joined(separator: ",")
+      let ins = s.currentRoute.inputs.map { $0.portType.rawValue }.joined(separator: ",")
       NSLog(
         "chanora_flutter: AVAudioSession actual: " +
         "sampleRate=\(s.sampleRate) " +
@@ -221,9 +202,18 @@ import AVFoundation
     let outputs = routeDescription.outputs.map { $0.portType.rawValue }.joined(separator: ",")
     NSLog("chanora_flutter: route change reason=\(reason.rawValue) outputs=\(outputs)")
 
-    if reason == .oldDeviceUnavailable || reason == .newDeviceAvailable {
-      iosAudioLifecycleChannel?.invokeMethod("handleRouteChange", arguments: nil)
-    }
+    // P1: Send the detailed route class to Rust on every route change,
+    // not just device plug/unplug. This covers:
+    //   - .newDeviceAvailable / .oldDeviceUnavailable (headset plug/unplug)
+    //   - .override (speaker/earpiece toggle)
+    //   - .categoryChange (session category changed)
+    //   - .wakeFromSleep (device woke from sleep)
+    //   - .routeConfigurationChange (BT HFP connect/disconnect)
+    // The Rust side uses the route class to recompute the processing
+    // policy (route_policy.rs) and reset AEC delay state if needed.
+    let routeClass = classifyAudioRoute(routeDescription)
+    NSLog("chanora_flutter: route class=\(routeClass) reason=\(reason.rawValue)")
+    iosAudioLifecycleChannel?.invokeMethod("handleRouteChange", arguments: routeClass)
   }
 
   @objc private func handleInterruption(_ notification: Notification) {
@@ -249,11 +239,115 @@ import AVFoundation
     }
   }
 
+  @objc private func handleMediaServicesReset(_ notification: Notification) {
+    NSLog("chanora_flutter: media services reset")
+    do {
+      let session = AVAudioSession.sharedInstance()
+      try session.setCategory(
+        .playAndRecord,
+        mode: .default,
+        options: [.defaultToSpeaker, .allowBluetoothHFP, .allowBluetoothA2DP]
+      )
+      try session.setPreferredIOBufferDuration(0.02)
+      try session.setPreferredSampleRate(48000.0)
+      try session.setActive(true, options: [])
+      logAudioSessionState(context: "mediaServicesWereReset")
+    } catch {
+      NSLog("chanora_flutter: AVAudioSession media-services reset rebuild failed: \(error)")
+    }
+    // P1: After rebuilding the session, send the current route class to
+    // Rust so it can recompute the processing policy and reset the
+    // AudioUnit. The Rust side handles this via ios_handle_media_services_reset
+    // which calls ios_restart_voice_unit.
+    let routeClass = classifyAudioRoute(AVAudioSession.sharedInstance().currentRoute)
+    NSLog("chanora_flutter: media services reset complete, route=\(routeClass)")
+    iosAudioLifecycleChannel?.invokeMethod("handleMediaServicesReset", arguments: routeClass)
+  }
+
+  override func applicationWillResignActive(_ application: UIApplication) {
+    iosAudioLifecycleChannel?.invokeMethod("handleWillResignActive", arguments: nil)
+  }
+
+  override func applicationDidEnterBackground(_ application: UIApplication) {
+    iosAudioLifecycleChannel?.invokeMethod("handleDidEnterBackground", arguments: nil)
+  }
+
+  override func applicationWillEnterForeground(_ application: UIApplication) {
+    iosAudioLifecycleChannel?.invokeMethod("handleWillEnterForeground", arguments: nil)
+  }
+
+  override func applicationWillTerminate(_ application: UIApplication) {
+    iosAudioLifecycleChannel?.invokeMethod("handleWillTerminate", arguments: nil)
+  }
+
   func didInitializeImplicitFlutterEngine(_ engineBridge: FlutterImplicitEngineBridge) {
     GeneratedPluginRegistrant.register(with: engineBridge.pluginRegistry)
     iosAudioLifecycleChannel = FlutterMethodChannel(
       name: "chanora/ios_audio_lifecycle",
       binaryMessenger: engineBridge.applicationRegistrar.messenger()
     )
+    iosPlatformChannel = FlutterMethodChannel(
+      name: "chanora/ios_platform",
+      binaryMessenger: engineBridge.applicationRegistrar.messenger()
+    )
+    iosPlatformChannel?.setMethodCallHandler { call, result in
+      switch call.method {
+      case "getMicrophonePermissionState":
+        result(self.microphonePermissionStateString())
+      case "requestMicrophonePermission":
+        AVAudioSession.sharedInstance().requestRecordPermission { granted in
+          DispatchQueue.main.async {
+            result(granted ? "Granted" : self.microphonePermissionStateString())
+          }
+        }
+      case "openAppSettings":
+        guard let url = URL(string: UIApplication.openSettingsURLString) else {
+          result(false)
+          return
+        }
+        UIApplication.shared.open(url, options: [:]) { opened in
+          result(opened)
+        }
+      default:
+        result(FlutterMethodNotImplemented)
+      }
+    }
+  }
+
+  private func classifyAudioRoute(_ route: AVAudioSessionRouteDescription) -> String {
+    for output in route.outputs {
+      switch output.portType {
+      case .builtInReceiver:
+        return "Earpiece"
+      case .builtInSpeaker:
+        return "Speaker"
+      case .headphones, .usbAudio:
+        return "WiredHeadset"
+      case .bluetoothHFP:
+        return "BluetoothHfp"
+      case .bluetoothA2DP:
+        return "BluetoothA2dp"
+      default:
+        break
+      }
+    }
+    return "Unknown"
+  }
+
+  private func microphonePermissionStateString() -> String {
+    switch AVAudioSession.sharedInstance().recordPermission {
+    case .granted:
+      return "Granted"
+    case .denied:
+      return "Denied"
+    case .undetermined:
+      return "NotDetermined"
+    @unknown default:
+      return "Unknown"
+    }
+  }
+
+  deinit {
+    NotificationCenter.default.removeObserver(self)
   }
 }

apps/chanora_flutter/ios/Runner/Info.plist

@@ -4,6 +4,9 @@
 <dict>
 	<key>CADisableMinimumFrameDurationOnPhone</key>
 	<true/>
+	<!-- Opt into ProMotion / high-refresh-rate CADisplayLink ranges on
+	     supported iPhones. Flutter's iOS embedder reads this key; no
+	     additional Flutter package is required for dynamic refresh. -->
 	<key>CFBundleDevelopmentRegion</key>
 	<string>$(DEVELOPMENT_LANGUAGE)</string>
 	<key>CFBundleDisplayName</key>
@@ -74,11 +77,6 @@
 		<string>UIInterfaceOrientationLandscapeLeft</string>
 		<string>UIInterfaceOrientationLandscapeRight</string>
 	</array>
-	<!-- Make Chanora's Documents folder visible to the Files.app and
-	     accessible via iTunes / Finder file-sharing. We write
-	     diagnostic logs (chanora.log) into Documents/ so users can
-	     export them for support. Both keys are required for the
-	     "On My iPhone -> Chanora" listing to appear in Files.app. -->
 	<key>UIFileSharingEnabled</key>
 	<true/>
 	<key>LSSupportsOpeningDocumentsInPlace</key>