From da67d316052a78de4d7f284c75f3b8e4b9542d21 Mon Sep 17 00:00:00 2001
From: Rob Walch <robwalch@users.noreply.github.com>
Date: Tue, 3 Dec 2024 15:07:11 -0800
Subject: [PATCH] Fix loading of audio media options with the same URI as the
 current level (#6887)

Resolves #6859
Resolves #6783 (Fixed with #6785 but regressed with #6845)
---
 src/controller/audio-track-controller.ts   | 8 ++++----
 src/controller/interstitials-controller.ts | 4 ++++
 src/controller/stream-controller.ts        | 8 ++++----
 src/utils/rendition-helper.ts              | 5 +++++
 4 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/src/controller/audio-track-controller.ts b/src/controller/audio-track-controller.ts
index 6804bcf962e..433fed22b60 100644
--- a/src/controller/audio-track-controller.ts
+++ b/src/controller/audio-track-controller.ts
@@ -8,6 +8,7 @@ import {
   findClosestLevelWithAudioGroup,
   findMatchingOption,
   matchesOption,
+  useAlternateAudio,
 } from '../utils/rendition-helper';
 import type Hls from '../hls';
 import type {
@@ -401,11 +402,10 @@ class AudioTrackController extends BasePlaylistController {
     if (!this.shouldLoadPlaylist(audioTrack)) {
       return;
     }
-    if (audioTrack.url === this.hls.levels[this.hls.loadLevel]?.uri) {
-      // Do not load audio rendition with URI matching main variant URI
-      return;
+    // Do not load audio rendition with URI matching main variant URI
+    if (useAlternateAudio(audioTrack.url, this.hls)) {
+      this.scheduleLoading(audioTrack, hlsUrlParameters);
     }
-    this.scheduleLoading(audioTrack, hlsUrlParameters);
   }
 
   protected loadingPlaylist(
diff --git a/src/controller/interstitials-controller.ts b/src/controller/interstitials-controller.ts
index 69a919d044f..0c23799e989 100644
--- a/src/controller/interstitials-controller.ts
+++ b/src/controller/interstitials-controller.ts
@@ -1273,6 +1273,10 @@ MediaSource ${JSON.stringify(attachMediaSourceData)} from ${logFromSource}`,
   }
 
   private onLevelUpdated(event: Events.LEVEL_UPDATED, data: LevelUpdatedData) {
+    if (data.level === -1) {
+      // level was removed
+      return;
+    }
     const main = this.hls.levels[data.level];
     const currentSelection = {
       ...(this.mediaSelection || this.altSelection),
diff --git a/src/controller/stream-controller.ts b/src/controller/stream-controller.ts
index e02055a2b74..1c2c6727f82 100644
--- a/src/controller/stream-controller.ts
+++ b/src/controller/stream-controller.ts
@@ -11,6 +11,7 @@ import { PlaylistContextType, PlaylistLevelType } from '../types/loader';
 import { ChunkMetadata } from '../types/transmuxer';
 import { BufferHelper } from '../utils/buffer-helper';
 import { pickMostCompleteCodecName } from '../utils/codecs';
+import { useAlternateAudio } from '../utils/rendition-helper';
 import type { FragmentTracker } from './fragment-tracker';
 import type Hls from '../hls';
 import type { Fragment, MediaFragment } from '../loader/fragment';
@@ -851,9 +852,10 @@ export default class StreamController
     event: Events.AUDIO_TRACK_SWITCHING,
     data: AudioTrackSwitchingData,
   ) {
+    const hls = this.hls;
     // if any URL found on new audio track, it is an alternate audio track
     const fromAltAudio = this.altAudio === AlternateAudio.SWITCHED;
-    const altAudio = !!data.url;
+    const altAudio = useAlternateAudio(data.url, hls);
     // if we switch on main audio, ensure that main fragment scheduling is synced with media.buffered
     // don't do anything if we switch to alt audio: audio stream controller is handling it.
     // we will just have to change buffer scheduling on audioTrackSwitched
@@ -878,7 +880,6 @@ export default class StreamController
         // Reset audio transmuxer so when switching back to main audio we're not still appending where we left off
         this.resetTransmuxer();
       }
-      const hls = this.hls;
       // If switching from alt to main audio, flush all audio and trigger track switched
       if (fromAltAudio) {
         hls.trigger(Events.BUFFER_FLUSHING, {
@@ -898,8 +899,7 @@ export default class StreamController
     event: Events.AUDIO_TRACK_SWITCHED,
     data: AudioTrackSwitchedData,
   ) {
-    const trackId = data.id;
-    const altAudio = !!this.hls.audioTracks[trackId].url;
+    const altAudio = useAlternateAudio(data.url, this.hls);
     if (altAudio) {
       const videoBuffer = this.videoBuffer;
       // if we switched on alternate audio, ensure that main fragment scheduling is synced with video sourcebuffer buffered
diff --git a/src/utils/rendition-helper.ts b/src/utils/rendition-helper.ts
index ee65e2df8bb..ea3ec2ecebe 100644
--- a/src/utils/rendition-helper.ts
+++ b/src/utils/rendition-helper.ts
@@ -1,6 +1,7 @@
 import { codecsSetSelectionPreferenceValue } from './codecs';
 import { getVideoSelectionOptions } from './hdr';
 import { logger } from './logger';
+import type Hls from '../hls';
 import type { Level, VideoRange } from '../types/level';
 import type {
   AudioSelectionOption,
@@ -500,3 +501,7 @@ function searchDownAndUpList(
   }
   return -1;
 }
+
+export function useAlternateAudio(audioTrackUrl: string, hls: Hls): boolean {
+  return !!audioTrackUrl && audioTrackUrl !== hls.levels[hls.loadLevel]?.uri;
+}