Enable EPUB TOC in DivinaReader (nav.xhtml / toc.ncx) + full-row clickable TOC

[PickledCakes]

Summary

• Add EPUB Table of Contents to the Divina image reader by consuming the Readium webpub manifest.
• Make TOC items full-row clickable for easier navigation (not just the anchor text).

Motivation

Komga’s EpubReader already exposes TOC for novels, and Thorium (also Divina-based) supports EPUB TOC. This change brings parity for manga/visual EPUBs inside Divina.

What’s changed

• komga-webui/src/views/DivinaReader.vue
  • Fetch manifest via bookManifestUrl(bookId).
  • Build TOC entries from pub.toc (fallback to pub.landmarks if toc is missing/empty).
  • Resolve href → page by mapping against readingOrder (spine); ignore unresolved/broken hrefs.
  • Only show the TOC button when entries exist.
• komga-webui/src/components/TocList.vue
  • Emit goto with the target page.
  • Make the entire row clickable/tappable to jump to the entry.

No server/API changes. Pure web-UI enhancement.

Behavior

• Clicking the TOC button opens a drawer listing chapters/sections.
• Clicking anywhere on a row navigates to the corresponding page.
• If a publication has no TOC (or landmarks), the button is hidden and the reader behaves as before.

Edge cases & fallback logic

• Prioritize toc; fallback to landmarks.
• If an entry’s href doesn’t match a spine item, skip it (prevents broken anchors).
• Reading direction (RTL/LTR) and reader settings are unchanged.

Testing

• Verified with EPUBs containing:
  • nav.xhtml (HTML5 navigation)
  • toc.ncx (legacy NCX)
• Confirmed navigation works with R→L and L→R page turns.
• Web-UI build passes with no ESLint/TS errors.

Limitations / future work

• Hierarchical TOC expand/collapse relies on TocList. Additional caret/expand logic can be added later once we have good multi-level samples.
• This PR does not modify EpubReader (novel) behavior.

Risk

Low. Changes are isolated to DivinaReader and TocList. When no TOC exists, UI is unchanged.

[gotson]

i don't understand the motivation, can you maybe explain what kind of books would be browsed as DiViNa but have a TOC ?

[PickledCakes]

i don't understand the motivation, can you maybe explain what kind of books would be browsed as DiViNa but have a TOC ?

These are image-centric EPUB 3 manga (all fixed-layout) that still ship with a proper TOC (nav.xhtml or legacy toc.ncx). They render in Komga with DiViNa because the content is page images, but they do have a TOC that’s useful for jumping between chapters/extras.

In my library (~6,500 manga volumes), ~90% come from official stores and include a structured TOC. Before switching to Komga, I regularly used that TOC in the vendors’ apps to jump between chapters; I’d like the same workflow in Komga.

I’m happy to provide sample manga EPUBs with valid nav.xhtml/toc.ncx if that helps with review.

[gotson]

thanks for the context. I don't think solving this in the frontend is the right way to do it. I would prefer to have some sort of support for generic TOC, which could also work for PDF, and i think ComicInfo.xml also has some kind of support for bookmarks.

I won't be accepting this PR, but i'm sure that will work for your own case.