fix: playback of series with large set of episodes

[maybeanerd]

Changes

Fetch episode info for a single episode instead of all episodes when attemtping to start playing an episode.

Updated changes: #5786 (comment)

Issues

Fixes #5779

[maybeanerd]

I tested all behavior I could think of to see if this change broke anything - did not find any issues.
But I would prefer somebody with deeper knowledge of the system to check if this breaks anything? Seems like an awfully simple change that could change a lot of behavior.

[dmitrylyzo]

AFAIK, that way you can't switch to the next episode from the player and you have to start each episode manually or start playing the entire show or season.

[maybeanerd]

Oh that's a good point.
I'll try testing that behavior later.

[maybeanerd]

You were right, it broke that.
So, the solution might be an inbetween, using some kind of pagination to not get all, but just the previous and next episode in addition to the current one? This would ofc also need to update when changing episode

I will look a bit into how this could be done, but again, if somebody has more knowledge and relevant info to share, please do so!

[thornbill]

Marking as a draft until a working solution is found.

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[maybeanerd]

Hey! I just rewrote the solution to stop breaking skipping in the player. It does still have some limitations, but IMO it's a good enough solution without adding a new pagination to the player and API itself, which seems like a very large undertaking.

The current solution:

1. limits the episodes when starting to play from an episode directly: to the current season. this means the player will not be able to skip to previous or next seasons, and will also exit when the season is finished. IMO this is not a bad tradeoff for the payloads to stay within reasonable sizes. This is the same behavior as it already was when starting to play a specific season

2. does not change the behavior when playing a specific season. the response was already limited to that season.

3. limits the episodes when starting to play from the general series overview: to the 100 first episodes. This means that the player will not be able to continue playing, or skip to, the 101st episode (no matter how many seasons). IMO this is something that will not happen when starting to play a series from the very start, so it's a good enough tradeoff.

[maybeanerd]

I also looked into using limit for the "play an episode" request, but I was not able to correctly set the offset. The API (to my knowledge) supports the startItemId , but this would limit going back inside the player, as it would be missing previous episodes.
I also tried using startIndex, and e.g. subtracting limit/2 from it, but this does not work if you e.g. only have season 2 in your library. The episode index of the first episode in season2 could be 100, which would end up providing an offset that skips the entirety of season2 (because season1 doesn't exist on the server at all)

Therefore limiting to the currently selected season seemed like the best approach to me.
If you have any other/better approaches, please do let me know

[maybeanerd]

@dmitrylyzo
ping because I don't know if you'll get notified about this PR update automatically
Not trying to stress you, just wanted to make sure it ends up in your inbox 👍