How to handle images zipped together?

[hmontaner]

Images in my server are organised into zipped groups for performance reasons.
I load them by passing two parameters, the URL of the zip file and the name of the file in that zip:
imageView.load(MyData("https://mydomain.com/my_zip.zip", "my_image.jpeg"))
To allow that, I've implemented my custom fetcher that does the following:

1. Download zip file.
2. Extract the relevant file from the zip.
3. Return the image in that file.

This works fine. However, Coil will download the zip again if a second request targets the same zip file and a different image inside that zip.
To solve this, I'm thinking of modifyig the fetcher to cache the rest of images in the zip file but I'm not sure how to do this.
However, this won't solve the problem of two parallel requests to two different images targeting the same zip file. Ideally, I would like to block one of the requests until the other has downloaded and extracted the zip. Any idea how best to do this?