Add a way to see how many pages you need to read to get to the next chapter.

[FlafyDev]

Title. Including sub chapters.

The problem is with anchors

1. What if the next chapter is in the same file but points to an anchor you haven't reached yet?

Right now the renderer is sending how many anchors you've currently passed in the current file. This is used by the reader app to correctly determine on which chapter you are in case there are multiple chapters pointing to the same file but different anchors).

My idea is instead of sending the passed anchors of the current file, send all of the anchors of the current file together with the inner page they are on. This way the reader app can compute on its own how many anchors have passed. And can also determine how many inner pages until the next chapter.

2. What if the next chapter is in a different file but points to an anchor?

You wouldn't be able to determine the percentage of how far an anchor is without having the file loaded.
This is solved by #6

Task list

• 1 solved. Change from passed anchors to a map of anchors and their inner page.
• 2 solved. Implement When preprocessing a book, get the location(a number between 0-1) of each anchor in its own file. #6