How easy would it be to add other sites? I want to add Booklive for Japanese books since they have a consistent cover URL scheme. Maybe Amazon JP too.
Booklive example:
https://booklive.jp/product/index/ti...859/vol_no/001
The high-res cover's URL is:
https://res.booklive.jp/331859/001/thumbnail/X.jpg
So the format would be:
https://res.booklive.jp/<title_id>/<vol_no>/thumbnail/X.jpg