From 58151d71c5b806ece26345ba2fc37d3a5dbe7a3f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=A0imon=20Brandner?= <simon.bra.ag@gmail.com>
Date: Wed, 23 Jun 2021 09:56:37 +0200
Subject: [PATCH] Handle mid-call output changes
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Signed-off-by: Šimon Brandner <simon.bra.ag@gmail.com>
---
 src/MediaDeviceHandler.ts                     | 27 ++++++++++++++++---
 .../tabs/user/VoiceUserSettingsTab.js         |  6 ++---
 src/components/views/voip/AudioFeed.tsx       | 18 ++++++++++---
 3 files changed, 40 insertions(+), 11 deletions(-)

diff --git a/src/MediaDeviceHandler.ts b/src/MediaDeviceHandler.ts
index 96fd764b98..8780cea359 100644
--- a/src/MediaDeviceHandler.ts
+++ b/src/MediaDeviceHandler.ts
@@ -18,6 +18,7 @@ limitations under the License.
 import SettingsStore from "./settings/SettingsStore";
 import { SettingLevel } from "./settings/SettingLevel";
 import { setMatrixCallAudioInput, setMatrixCallVideoInput } from "matrix-js-sdk/src/matrix";
+import EventEmitter from 'events';
 
 interface IMediaDevices {
     audioOutput: Array<MediaDeviceInfo>;
@@ -25,7 +26,22 @@ interface IMediaDevices {
     videoInput: Array<MediaDeviceInfo>;
 }
 
-export default class MediaDeviceHandler {
+export enum MediaDeviceHandlerEvent {
+    AudioOutputChanged = "audio_output_changed",
+    AudioInputChanged = "audio_input_changed",
+    VideoInputChanged = "video_input_changed",
+}
+
+export default class MediaDeviceHandler extends EventEmitter {
+    private static internalInstance;
+
+    public static get instance(): MediaDeviceHandler {
+        if (!MediaDeviceHandler.internalInstance) {
+            MediaDeviceHandler.internalInstance = new MediaDeviceHandler();
+        }
+        return MediaDeviceHandler.internalInstance;
+    }
+
     static async hasAnyLabeledDevices(): Promise<boolean> {
         const devices = await navigator.mediaDevices.enumerateDevices();
         return devices.some(d => Boolean(d.label));
@@ -68,18 +84,21 @@ export default class MediaDeviceHandler {
         setMatrixCallVideoInput(videoDeviceId);
     }
 
-    static setAudioOutput(deviceId: string) {
+    public setAudioOutput(deviceId: string) {
         SettingsStore.setValue("webrtc_audiooutput", null, SettingLevel.DEVICE, deviceId);
+        this.emit(MediaDeviceHandlerEvent.AudioOutputChanged, deviceId);
     }
 
-    static setAudioInput(deviceId: string) {
+    public setAudioInput(deviceId: string) {
         SettingsStore.setValue("webrtc_audioinput", null, SettingLevel.DEVICE, deviceId);
         setMatrixCallAudioInput(deviceId);
+        this.emit(MediaDeviceHandlerEvent.AudioInputChanged, deviceId);
     }
 
-    static setVideoInput(deviceId: string) {
+    public setVideoInput(deviceId: string) {
         SettingsStore.setValue("webrtc_videoinput", null, SettingLevel.DEVICE, deviceId);
         setMatrixCallVideoInput(deviceId);
+        this.emit(MediaDeviceHandlerEvent.VideoInputChanged, deviceId);
     }
 
     static getAudioOutput(): string {
diff --git a/src/components/views/settings/tabs/user/VoiceUserSettingsTab.js b/src/components/views/settings/tabs/user/VoiceUserSettingsTab.js
index 962f1fcd44..f730406eed 100644
--- a/src/components/views/settings/tabs/user/VoiceUserSettingsTab.js
+++ b/src/components/views/settings/tabs/user/VoiceUserSettingsTab.js
@@ -100,21 +100,21 @@ export default class VoiceUserSettingsTab extends React.Component {
     };
 
     _setAudioOutput = (e) => {
-        MediaDeviceHandler.setAudioOutput(e.target.value);
+        MediaDeviceHandler.instance.setAudioOutput(e.target.value);
         this.setState({
             activeAudioOutput: e.target.value,
         });
     };
 
     _setAudioInput = (e) => {
-        MediaDeviceHandler.setAudioInput(e.target.value);
+        MediaDeviceHandler.instance.setAudioInput(e.target.value);
         this.setState({
             activeAudioInput: e.target.value,
         });
     };
 
     _setVideoInput = (e) => {
-        MediaDeviceHandler.setVideoInput(e.target.value);
+        MediaDeviceHandler.instance.setVideoInput(e.target.value);
         this.setState({
             activeVideoInput: e.target.value,
         });
diff --git a/src/components/views/voip/AudioFeed.tsx b/src/components/views/voip/AudioFeed.tsx
index 80d658e7ee..d29caf789e 100644
--- a/src/components/views/voip/AudioFeed.tsx
+++ b/src/components/views/voip/AudioFeed.tsx
@@ -17,7 +17,7 @@ limitations under the License.
 import React, {createRef} from 'react';
 import { CallFeed, CallFeedEvent } from 'matrix-js-sdk/src/webrtc/callFeed';
 import { logger } from 'matrix-js-sdk/src/logger';
-import MediaDeviceHandler from "../../../MediaDeviceHandler";
+import MediaDeviceHandler, { MediaDeviceHandlerEvent } from "../../../MediaDeviceHandler";
 
 interface IProps {
     feed: CallFeed,
@@ -27,19 +27,25 @@ export default class AudioFeed extends React.Component<IProps> {
     private element = createRef<HTMLAudioElement>();
 
     componentDidMount() {
+        MediaDeviceHandler.instance.addListener(
+            MediaDeviceHandlerEvent.AudioOutputChanged,
+            this.onAudioOutputChanged,
+        );
         this.props.feed.addListener(CallFeedEvent.NewStream, this.onNewStream);
         this.playMedia();
     }
 
     componentWillUnmount() {
+        MediaDeviceHandler.instance.removeListener(
+            MediaDeviceHandlerEvent.AudioOutputChanged,
+            this.onAudioOutputChanged,
+        );
         this.props.feed.removeListener(CallFeedEvent.NewStream, this.onNewStream);
         this.stopMedia();
     }
 
-    private playMedia() {
+    private onAudioOutputChanged = (audioOutput: string) => {
         const element = this.element.current;
-        const audioOutput = MediaDeviceHandler.getAudioOutput();
-
         if (audioOutput) {
             try {
                 // This seems quite unreliable in Chrome, although I haven't yet managed to make a jsfiddle where
@@ -52,7 +58,11 @@ export default class AudioFeed extends React.Component<IProps> {
                 logger.warn("Couldn't set requested audio output device: using default", e);
             }
         }
+    }
 
+    private playMedia() {
+        const element = this.element.current;
+        this.onAudioOutputChanged(MediaDeviceHandler.getAudioOutput());
         element.muted = false;
         element.srcObject = this.props.feed.stream;
         element.autoplay = true;