feat: Calculate mediaTimeSpent based on current time (#709)

Co-authored-by: Mohammed Mustafa <[email protected]>

Author: mmustafa-tse

src/session.ts

@@ -96,7 +96,7 @@ export class MediaSession {
     private mediaSessionStartTimestamp = Date.now(); //Timestamp created on logMediaSessionStart event
     private mediaSessionEndTimestamp = Date.now(); //Timestamp updated when any event is loggged
     private mediaTimeSpent() {
-        return this.mediaSessionEndTimestamp - this.mediaSessionStartTimestamp;
+        return Date.now() - this.mediaSessionStartTimestamp;
     }
     private currentPlaybackStartTimestamp?: number; //Timestamp for beginning of current playback
     private storedPlaybackTime = 0; //On Pause calculate playback time and clear currentPlaybackTime

test/session.test.ts

@@ -1463,4 +1463,29 @@ describe('MediaSession', () => {
             });
         });
     });
+
+    describe('Media Session Attributes', () => {
+        it('should get mediaTimeSpent based on current time', async () => {
+            const options = {
+                customAttributes: {
+                    content_rating: 'epic',
+                },
+                currentPlayheadPosition: 0,
+            };
+
+            // logPlay is triggered to start media content time tracking.
+            mpMedia.logPlay(options);
+            // 100ms delay added to account for the time spent on media content.
+            await new Promise(f => setTimeout(f, 100));
+            mpMedia.logPause(options);
+            // Another 100ms delay added after logPause is triggered to account for time spent on media session (total = +200ms).
+            await new Promise(f => setTimeout(f, 100));
+
+            const mpMediaTimeSpent = mpMedia['mediaTimeSpent']();
+            // the mediaTimeSpent varies in value each test run by a millisecond or two (i,e value is could be 200ms, 201ms, 202ms)
+            // and we can't determine the exact value, hence the greaterThanOrEqual and lessThanOrEqual tests.
+            expect(mpMediaTimeSpent).to.greaterThanOrEqual(200);
+            expect(mpMediaTimeSpent).to.lessThanOrEqual(300);
+        });
+    });
 });