Yeah, I think, but that's an easy part. One just need to grab some data from DB and then put some other data back to DB. If someone is interested, all DB-related code is in this file:
https://github.com/anareaty/PocketBo...pp/js/async.js . Everythin else is just a GUI.
Basically the DB has several tables. Most of books info is in the "books_impl" table including title, author, etc. and unique book ids. Shelfs info is in "bookshelfs" table, there are shelf names and shelf ids. And "bookshelfs_books" table holds information of assotiations between book ids and shelfs ids. We add or delete rows from the last table - we move books between shelves. For the most part it's all.