[Media3] Add support for queues on media3 sessions

[sztomek]

Description

With media3_session flag enabled we didn't support up next queue. This PR addresses that.

Fixes PCDROID-533 https://linear.app/a8c/issue/PCDROID-533/media3-wearos-media-session-up-next-button-disabled

Testing Instructions

1. Install wear app with FF ON
2. Put together a queue
3. Start playing an episode
4. Start an excercise on your watch
5. Swipe right to see the media session
6. Verify up next button works

Checklist

• If this is a user-facing change, I have added an entry in CHANGELOG.md
• Ensure the linter passes (./gradlew spotlessApply to automatically apply formatting/linting)
• I have considered whether it makes sense to add tests for my changes
• All strings that need to be localized are in modules/services/localization/src/main/res/values/strings.xml
• Any jetpack compose components I added or changed are covered by compose previews
• I have updated (or requested that someone edit) the spreadsheet to reflect any new or changed analytics.

[Copilot]

Pull request overview

Adds Media3 “Up Next” queue support by exposing a queue-backed Timeline from the session player and wiring Up Next queue updates into the Media3 session so external controllers (e.g., Wear OS media session UI) can browse/select queued episodes.

Changes:

• Extend PocketCastsForwardingPlayer to maintain queue items, expose a Timeline, and handle queue-item selection via seekTo(mediaItemIndex, …).
• Observe UpNextQueue changes in MediaSessionManager and push mapped MediaItems into the forwarding player + notify Media3 library children changes.
• Allow controllers to request timeline info by adding COMMAND_GET_TIMELINE to Media3 connection commands.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 6 comments.

File	Description
modules/services/repositories/src/main/java/au/com/shiftyjelly/pocketcasts/repositories/playback/PocketCastsForwardingPlayer.kt	Adds queue state + timeline exposure and queue-item seeking support for Media3 controllers.
modules/services/repositories/src/main/java/au/com/shiftyjelly/pocketcasts/repositories/playback/MediaSessionManager.kt	Wires Up Next queue updates into the Media3 session/player and handles queue-item selection.
modules/services/repositories/src/main/java/au/com/shiftyjelly/pocketcasts/repositories/playback/Media3SessionCallback.kt	Extends granted player commands to include timeline access.

[geekygecko]

I could be doing something wrong but the Up Next doesn't seem to be enabled for me.

I don't think the Media3 code sets the mediaSession.setQueue so that isn't showing as enabled but does with the legacy player.

[wpmobilebot]

Version 8.10 has now entered code-freeze, so the milestone of this PR has been updated to 8.11.

[sztomek]

@geekygecko made some changes in 46779cf - could you please try again?

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

[geekygecko]

@sztomek it still doesn't seem to be working for me. I had a quick look and couldn't figure out a fix.

I did experience one crash which might be related to this code change.

androidx/media3/session/PlayerWrapper.java

  public PositionInfo createPositionInfo() {
    boolean canAccessCurrentMediaItem = isCommandAvailable(COMMAND_GET_CURRENT_MEDIA_ITEM);
    boolean canAccessTimeline = isCommandAvailable(COMMAND_GET_TIMELINE);
    int currentMediaItemIndex = canAccessTimeline ? getCurrentMediaItemIndex() : 0;
    checkState(currentMediaItemIndex >= 0);

getCurrentMediaItemIndex has to return a value greater than or equal to 0. Our PocketCastsForwardingPlayer implementation has the following:

    override fun getCurrentMediaItemIndex(): Int {
        // Per Player contract, return C.INDEX_UNSET when there's no current window.
        // Returning 0 would make controllers think the first queue item is currently
        // playing when playback is idle, and prevents the legacy bridge from setting
        // a valid active queue item id (breaks Wear OS Up Next affordance).
        return if (currentMediaItem == MediaItem.EMPTY) C.INDEX_UNSET else 0
    }

The value of INDEX_UNSET = -1;. I think the value of our current item would always be 0.

[sztomek]

thanks @geekygecko
i've pushed a new commit that addresses the issue you've flagged. i was also able to verify on AUTOMOTIVE that the up next queue works.

Screen_recording_20260423_114322.mp4

Unfortunately i'm not seeing the same UI on my Galaxy Watch 4 during an excercise that you do and I didn't find any ways to bring it up on a watch emulator either...
could you please check again? 🙏