I made a ton of improvements to the asset swapper! And fixed a bug with the music player which is cool technically, so I’ll start with that. The player uses the GSMTC api, which is async, but egui doesn’t really like async. So, I made it so that every time you wanted to run some command on the current session, it would start up a new thread. This was less than ideal for a few reasons:

1. terrible performance
2. race conditions could happen just… in Windows itself

The main problem was 2: for example, if you skipped a replay too fast, the Play command from the end of the replay might actually reach Windows before the Pause command from the replay start, leaving your music paused.
So instead, it starts one dedicated worker thread which has a channel which receives a Box<dyn FnOnce(Session)>, and executes at most one command every 50ms (only one command per loop, fixed loop time of 50ms). It’s really interesting because you actually end up sending a closure through a channel, which feels funny but when you really think about it it’s just ownership semantics. But, that’s working great now!
On to swapper improvements! First, I moved most of the swapper module to anyhow handling (it’s heaven!), and I also modernized the upk api a bit since it was basically dragged directly from the proof-of-concept repo, meaning it was not really application-ready. Also, it previously looked at the game’s webcache to decode the AES keys for header decryption, but now it uses the wonderful Toga-Files repository along with a really nice caching layer for it to load items and their associated API keys.
Having access to the actual item data is also way better since you don’t have to manually type in a package name which is kinda weird for any normal person. Now, you can select it from a dropdown instead! I love UX.