feat: added onPositionChanged event

Author: Maciej Makowski

packages/react-native-audio-api/common/cpp/audioapi/HostObjects/AudioBufferQueueSourceNodeHostObject.h

@@ -21,6 +21,10 @@ class AudioBufferQueueSourceNodeHostObject
                 JSI_EXPORT_PROPERTY_GETTER(AudioBufferQueueSourceNodeHostObject, detune),
                 JSI_EXPORT_PROPERTY_GETTER(AudioBufferQueueSourceNodeHostObject, playbackRate));
 
+        addSetters(
+                JSI_EXPORT_PROPERTY_SETTER(AudioBufferQueueSourceNodeHostObject, onPositionChanged),
+                JSI_EXPORT_PROPERTY_SETTER(AudioBufferQueueSourceNodeHostObject, onPositionChangedInterval));
+
         // start method is overridden in this class
         functions_->erase("start");
 
@@ -46,6 +50,20 @@ class AudioBufferQueueSourceNodeHostObject
         return jsi::Object::createFromHostObject(runtime, playbackRateHostObject);
     }
 
+    JSI_PROPERTY_SETTER(onPositionChanged) {
+        auto audioBufferQueueSourceNode =
+                std::static_pointer_cast<AudioBufferQueueSourceNode>(node_);
+
+        audioBufferQueueSourceNode->setOnPositionChangedCallbackId(std::stoull(value.getString(runtime).utf8(runtime)));
+    }
+
+    JSI_PROPERTY_SETTER(onPositionChangedInterval) {
+        auto audioBufferQueueSourceNode =
+                std::static_pointer_cast<AudioBufferQueueSourceNode>(node_);
+
+        audioBufferQueueSourceNode->setOnPositionChangedInterval(value.getNumber());
+    }
+
     JSI_HOST_FUNCTION(start) {
         auto when = args[0].getNumber();
         auto offset = args[1].getNumber();

packages/react-native-audio-api/common/cpp/audioapi/core/sources/AudioBufferQueueSourceNode.cpp

@@ -27,6 +27,8 @@ AudioBufferQueueSourceNode::AudioBufferQueueSourceNode(
       std::make_shared<signalsmith::stretch::SignalsmithStretch<float>>();
   stretch_->presetDefault(channelCount_, context_->getSampleRate(), true);
 
+  onPositionChangedInterval_ = static_cast<int>(context_->getSampleRate() / 10);
+
   isInitialized_ = true;
 }
 
@@ -106,6 +108,28 @@ double AudioBufferQueueSourceNode::getStopTime() const {
       static_cast<int>(vReadIndex_), context_->getSampleRate());
 }
 
+void AudioBufferQueueSourceNode::setOnPositionChangedCallbackId(uint64_t callbackId) {
+    onPositionChangedCallbackId_ = callbackId;
+}
+
+void AudioBufferQueueSourceNode::sendOnPositionChangedEvent() {
+    if (onPositionChangedTime_ > onPositionChangedInterval_) {
+      std::unordered_map<std::string, EventValue> body = {
+              {"value", getStopTime()}, {"bufferId", bufferId_}};
+
+      context_->audioEventHandlerRegistry_->invokeHandlerWithEventBody(
+              "positionChanged", onPositionChangedCallbackId_, body);
+
+      onPositionChangedTime_ = 0;
+    }
+
+    onPositionChangedTime_ += RENDER_QUANTUM_SIZE;
+}
+
+void AudioBufferQueueSourceNode::setOnPositionChangedInterval(int interval) {
+    onPositionChangedInterval_ = static_cast<int>(context_->getSampleRate() * 1000 / static_cast<float>(interval));
+}
+
 /**
  * Helper functions
  */
@@ -133,6 +157,9 @@ void AudioBufferQueueSourceNode::processWithPitchCorrection(
     return;
   }
 
+  // Send position changed event
+  sendOnPositionChangedEvent();
+
   auto framesNeededToStretch =
       static_cast<int>(playbackRate * static_cast<float>(framesToProcess));
   auto stretchedStartOffset =

packages/react-native-audio-api/common/cpp/audioapi/core/sources/AudioBufferQueueSourceNode.h

@@ -27,6 +27,10 @@ class AudioBufferQueueSourceNode : public AudioScheduledSourceNode {
     void enqueueBuffer(const std::shared_ptr<AudioBuffer> &buffer, int bufferId, bool isLastBuffer);
     void disable() override;
 
+    void setOnPositionChangedCallbackId(uint64_t callbackId);
+    void setOnPositionChangedInterval(int interval);
+    void sendOnPositionChangedEvent();
+
  protected:
     std::mutex &getBufferLock();
     void processNode(const std::shared_ptr<AudioBus>& processingBus, int framesToProcess) override;
@@ -51,6 +55,11 @@ class AudioBufferQueueSourceNode : public AudioScheduledSourceNode {
     int bufferId_ = 0;
     bool isLastBuffer_ = false;
 
+    // positionChanged event props: callbackId, update interval in frames, time since last update in frames
+    uint64_t onPositionChangedCallbackId_ = 0;
+    int onPositionChangedInterval_;
+    int onPositionChangedTime_ = 0;
+
     void processWithPitchCorrection(const std::shared_ptr<AudioBus> &processingBus,
                                     int framesToProcess);
 

packages/react-native-audio-api/common/cpp/audioapi/core/sources/AudioBufferSourceNode.h

@@ -17,7 +17,7 @@ class AudioParam;
 class AudioBufferSourceNode : public AudioScheduledSourceNode {
  public:
   explicit AudioBufferSourceNode(BaseAudioContext *context, bool pitchCorrection);
-  ~AudioBufferSourceNode();
+  ~AudioBufferSourceNode() override;
 
   [[nodiscard]] bool getLoop() const;
   [[nodiscard]] double getLoopStart() const;

packages/react-native-audio-api/common/cpp/audioapi/core/sources/AudioScheduledSourceNode.cpp

@@ -10,9 +10,9 @@ namespace audioapi {
 
 AudioScheduledSourceNode::AudioScheduledSourceNode(BaseAudioContext *context)
     : AudioNode(context),
-      playbackState_(PlaybackState::UNSCHEDULED),
       startTime_(-1.0),
-      stopTime_(-1.0) {
+      stopTime_(-1.0),
+      playbackState_(PlaybackState::UNSCHEDULED) {
   numberOfInputs_ = 0;
 }
 

packages/react-native-audio-api/common/cpp/audioapi/core/sources/AudioScheduledSourceNode.h

@@ -56,7 +56,7 @@ class AudioScheduledSourceNode : public AudioNode {
 
   void handleStopScheduled();
 
-    uint64_t onEndedCallbackId_ = 0;
+  uint64_t onEndedCallbackId_ = 0;
 };
 
 } // namespace audioapi

packages/react-native-audio-api/common/cpp/audioapi/events/AudioEventHandlerRegistry.h

@@ -49,9 +49,10 @@ class AudioEventHandlerRegistry {
         "volumeChange",
     };
 
-    static constexpr std::array<std::string_view, 4> AUDIO_API_EVENT_NAMES = {
+    static constexpr std::array<std::string_view, 5> AUDIO_API_EVENT_NAMES = {
       "ended",
       "audioReady",
+      "positionChanged",
       "audioError",
       "systemStateChanged"
     };

packages/react-native-audio-api/src/core/AudioBufferQueueSourceNode.ts

@@ -4,6 +4,7 @@ import BaseAudioContext from './BaseAudioContext';
 import AudioBuffer from './AudioBuffer';
 import AudioParam from './AudioParam';
 import { InvalidStateError, RangeError } from '../errors';
+import { OnPositionChangedEventType } from '../events/types';
 
 export default class AudioBufferQueueSourceNode extends AudioScheduledSourceNode {
   readonly playbackRate: AudioParam;
@@ -48,4 +49,23 @@ export default class AudioBufferQueueSourceNode extends AudioScheduledSourceNode
     this.hasBeenStarted = true;
     (this.node as IAudioBufferQueueSourceNode).start(when, offset);
   }
+
+  // eslint-disable-next-line accessor-pairs
+  public set onPositionChanged(
+    callback: (event: OnPositionChangedEventType) => void
+  ) {
+    const subscription = this.audioEventEmitter.addAudioEventListener(
+      'positionChanged',
+      callback
+    );
+
+    (this.node as IAudioBufferQueueSourceNode).onPositionChanged =
+      subscription.subscriptionId;
+  }
+
+  // eslint-disable-next-line accessor-pairs
+  public set onPositionChangedInterval(value: number) {
+    (this.node as IAudioBufferQueueSourceNode).onPositionChangedInterval =
+      value;
+  }
 }

packages/react-native-audio-api/src/core/AudioScheduledSourceNode.ts

@@ -6,7 +6,7 @@ import { AudioEventEmitter } from '../events';
 
 export default class AudioScheduledSourceNode extends AudioNode {
   protected hasBeenStarted: boolean = false;
-  private readonly audioEventEmitter = new AudioEventEmitter(
+  protected readonly audioEventEmitter = new AudioEventEmitter(
     global.AudioEventEmitter
   );
 

packages/react-native-audio-api/src/events/types.ts

@@ -12,6 +12,11 @@ export interface OnEndedEventType {
   bufferId: number | undefined;
 }
 
+export interface OnPositionChangedEventType {
+  value: number;
+  bufferId: number;
+}
+
 interface OnInterruptionEventType {
   type: 'ended' | 'began';
   shouldResume: boolean;
@@ -48,6 +53,7 @@ export interface OnAudioReadyEventType {
 interface AudioAPIEvents {
   ended: OnEndedEventType;
   audioReady: OnAudioReadyEventType;
+  positionChanged: OnPositionChangedEventType;
   audioError: EventEmptyType; // to change
   systemStateChanged: EventEmptyType; // to change
 }

packages/react-native-audio-api/src/interfaces.ts

@@ -120,6 +120,11 @@ export interface IAudioBufferQueueSourceNode extends IAudioScheduledSourceNode {
     isLastBuffer: boolean
   ) => void;
   start: (when?: number, offset?: number) => void;
+
+  // passing subscriptionId(uint_64 in cpp, string in js) to the cpp
+  onPositionChanged: string;
+  // set how often the onPositionChanged event is called
+  onPositionChangedInterval: number;
 }
 
 export interface IAudioBuffer {