feat(contentHint): emit event on contentHint change

src/media/local-video-stream.spec.ts

@@ -2,7 +2,11 @@ import { createBrowserMock } from '../mocks/create-browser-mock';
 import MediaStreamStub from '../mocks/media-stream-stub';
 import { mocked } from '../mocks/mock';
 import { LocalStreamEventNames } from './local-stream';
-import { LocalVideoStream } from './local-video-stream';
+import {
+  LocalVideoStream,
+  LocalVideoStreamEventNames,
+  VideoContentHint,
+} from './local-video-stream';
 
 jest.mock('../mocks/media-stream-stub');
 
@@ -28,12 +32,20 @@ describe('localVideoStream', () => {
       // eslint-disable-next-line no-console
       console.log('stream constraints changed');
     });
+    videoStream.on(
+      LocalVideoStreamEventNames.ContentHintChange,
+      (contentHint: VideoContentHint) => {
+        // eslint-disable-next-line no-console
+        console.log(`stream contentHint changed to ${contentHint}`);
+      }
+    );
 
     videoStream.setUserMuted(true);
     videoStream.applyConstraints({
       height: 720,
       width: 1280,
     });
+    videoStream.contentHint = 'motion';
 
     expect(1).toBe(1);
   });

src/media/local-video-stream.ts

@@ -1,3 +1,4 @@
+import { AddEvents, TypedEvent, WithEventsDummyType } from '@webex/ts-events';
 import { logger } from '../util/logger';
 import { LocalStream, LocalStreamEventNames } from './local-stream';
 
@@ -12,10 +13,24 @@ export type AppliableVideoConstraints = Pick<
  */
 export type VideoContentHint = 'motion' | 'detail' | 'text' | '';
 
+export enum LocalVideoStreamEventNames {
+  ContentHintChange = 'content-hint-change',
+}
+
+interface LocalVideoStreamEvents {
+  [LocalVideoStreamEventNames.ContentHintChange]: TypedEvent<
+    (contentHint: VideoContentHint) => void
+  >;
+}
+
 /**
  * A video LocalStream.
  */
-export class LocalVideoStream extends LocalStream {
+class _LocalVideoStream extends LocalStream {
+  [LocalVideoStreamEventNames.ContentHintChange] = new TypedEvent<
+    (contentHint: VideoContentHint) => void
+  >();
+
   /**
    * Apply constraints to the stream.
    *
@@ -44,7 +59,10 @@ export class LocalVideoStream extends LocalStream {
    * @param hint - The content hint to set.
    */
   set contentHint(hint: VideoContentHint) {
-    this.inputTrack.contentHint = hint;
+    if (this.inputTrack.contentHint !== hint) {
+      this.inputTrack.contentHint = hint;
+      this[LocalVideoStreamEventNames.ContentHintChange].emit(hint);
+    }
   }
 
   /**
@@ -65,3 +83,9 @@ export class LocalVideoStream extends LocalStream {
     return activeSimulcastLayersNumber;
   }
 }
+
+export const LocalVideoStream = AddEvents<typeof _LocalVideoStream, LocalVideoStreamEvents>(
+  _LocalVideoStream
+);
+
+export type LocalVideoStream = _LocalVideoStream & WithEventsDummyType<LocalVideoStreamEvents>;