FR: If only one file is needed, don't bother creating the zip file

[thibaultmol]

No description provided.

[qgustavor]

Pull requests are welcome. Relevant code is here: https://github.com/qgustavor/mkv-extract/blob/main/src%2Froutes%2F%2Bpage.svelte#L98

[qgustavor]

Things to fix:

• Rename startZipExtraction to startZipCreation. IDK why I named it wrong 🤷
• Add a condition here to check if there's just a single stream selected, then handle this case separately in other function.

Code is kinda complex because, in order to reduce memory load, it tries to handle stream extraction by streaming the zip using streamsaver (or using the File Access API, which stores the extracted files direct to the file system without requiring a zip).

[qgustavor]

I forgot to fix the function name. 🤦‍♂️