From cfba1b07c65cba3463c9b0aa2640d6bde65cb9d5 Mon Sep 17 00:00:00 2001
From: Michael Weimann <michaelw@matrix.org>
Date: Fri, 3 Feb 2023 13:49:43 +0100
Subject: [PATCH] Broadcast time left should never be negative (#10070)

---
 .../models/VoiceBroadcastPlayback.ts               |  4 +++-
 .../models/VoiceBroadcastPlayback-test.tsx         | 14 ++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/voice-broadcast/models/VoiceBroadcastPlayback.ts b/src/voice-broadcast/models/VoiceBroadcastPlayback.ts
index 94ccaac1fb..0a5442cb62 100644
--- a/src/voice-broadcast/models/VoiceBroadcastPlayback.ts
+++ b/src/voice-broadcast/models/VoiceBroadcastPlayback.ts
@@ -441,7 +441,9 @@ export class VoiceBroadcastPlayback
     }
 
     public get timeLeftSeconds(): number {
-        return Math.round(this.durationSeconds) - this.timeSeconds;
+        // Sometimes the meta data and the audio files are a little bit out of sync.
+        // Be sure it never returns a negative value.
+        return Math.max(0, Math.round(this.durationSeconds) - this.timeSeconds);
     }
 
     public async skipTo(timeSeconds: number): Promise<void> {
diff --git a/test/voice-broadcast/models/VoiceBroadcastPlayback-test.tsx b/test/voice-broadcast/models/VoiceBroadcastPlayback-test.tsx
index ac4217e048..e7f4c8afcc 100644
--- a/test/voice-broadcast/models/VoiceBroadcastPlayback-test.tsx
+++ b/test/voice-broadcast/models/VoiceBroadcastPlayback-test.tsx
@@ -525,6 +525,20 @@ describe("VoiceBroadcastPlayback", () => {
 
                 it("should update the time", () => {
                     expect(playback.timeSeconds).toBe(11);
+                    expect(playback.timeLeftSeconds).toBe(2);
+                });
+            });
+
+            describe("and the chunk playback progresses across the actual time", () => {
+                // This can be the case if the meta data is out of sync with the actual audio data.
+
+                beforeEach(() => {
+                    chunk1Playback.clockInfo.liveData.update([15]);
+                });
+
+                it("should update the time", () => {
+                    expect(playback.timeSeconds).toBe(15);
+                    expect(playback.timeLeftSeconds).toBe(0);
                 });
             });