## Summary: Enable footnote anchor navigation in EPUB reader
This PR extracts the core anchor-to-page mapping mechanism from PR #1143
(TOC fragment navigation) to provide immediate footnote navigation
support. By merging this focused subset first, users get a complete
footnote experience now while simplifying the eventual review and merge
of the full #1143 PR.
---
## What this extracts from PR #1143
PR #1143 implements comprehensive TOC fragment navigation for EPUBs with
multi-chapter spine files. This PR takes only the anchor resolution
infrastructure:
- Anchor-to-page mapping in section cache: During page layout,
ChapterHtmlSlimParser records which page each HTML id attribute lands
on, serializing the map into the .bin cache file.
- Anchor resolution in `EpubReaderActivity`: When navigating to a
footnote link with a fragment (e.g., `chapter2.xhtml#note1`), the reader
resolves the anchor to a page number and jumps directly to it.
- Section file format change: Bumped to version 15, adds anchor map
offset in header.
---
## Simplified scope vs. PR #1143
To minimize conflicts and complexity, this PR differs from #1143 in key
ways:
* **Anchors tracked**
* **Origin:** Only TOC anchors (passed via `std::set`)
* **This branch:** All `id` attributes
* **Page breaks**
* **Origin**: Forces new page at TOC chapter boundaries
* **This branch:** None — natural flow
* **TOC integration**
* **Origin**: `tocBoundaries`, `getTocIndexForPage()`, chapter skip
* **This branch:** None — just footnote links
* **Bug fix**
* **This branch:** Fixed anchor page off-by-1/2 bug
The anchor recording bug (recording page number before `makePages()`
flushes previous block) was identified and fixed during this extraction.
The fix uses a deferred `pendingAnchorId` pattern that records the
anchor after page completion.
---
## Positioning for future merge
Changes are structured to minimize conflicts when #1143 eventually
merges:
- `ChapterHtmlSlimParser.cpp` `startElement()`: Both branches rewrite
the same if `(!idAttr.empty())` block. The merged version will combine
both approaches (TOC anchors get page breaks + immediate recording;
footnote anchors get deferred recording).
- `EpubReaderActivity.cpp` `render()`: The `pendingAnchor` resolution
block is positioned at the exact same insertion point where #1143 places
its `pendingTocIndex` block (line 596, right after `nextPageNumber`
assignment). During merge, both blocks will sit side-by-side.
---
## Why merge separately?
1. Immediate user value: Footnote navigation works now without waiting
for the full TOC overhaul
2. Easier review: ~100 lines vs. 500+ lines in #1143
3. Bug fix included: The page recording bug is fixed here and will carry
into #1143
4. Minimal conflicts: Structured for clean merge — both PRs touch the
same files but in complementary ways
---
### AI Usage
Did you use AI tools to help write this code? _**< YES >**_ Done by
Claude Opus 4.6
## Summary
**What is the goal of this PR?**
This change avoids the pattern of creating a `std::string` using
`.substr` in order to compare against a file extension literal.
```c++
std::string path;
if (path.length() >= 4 && path.substr(path.length() - 4) == ".ext")
```
The `checkFileExtension` utility has moved from StringUtils to
FsHelpers, to be available to code in lib/. The signature now accepts a
`std::string_view` instead of `std::string`, which makes the single
implementation reusable for Arduino `String`.
Added utility functions for commonly repeated extensions.
These changes **save about 2 KB of flash (5,999,427 to 5,997,343)**.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**NO**_
## Summary
**What is the goal of this PR?** Add a user setting to decide image
support: display, show placeholder instead, supress fully
Fixes#1289
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _**< NO >**_
## Summary
Ref discussion:
https://github.com/crosspoint-reader/crosspoint-reader/pull/1222#discussion_r2865402110
Important note that this is a bug-for-bug fix. In reality, this branch
`WiFi.status() == WL_CONNECTED` is pretty much a dead code because the
entry point of these 2 activities don't use wifi.
It is better to refactor the management of network though, but it's
better to be a dedicated PR.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? **NO**
## Summary
* Custom sleep screen images now load from /.sleep directory
(preferred), falling back to /sleep for backwards compatibility. The
dot-prefix keeps the directory hidden from the file browser.
* Rewrote User Guide section 3.6 to document all six sleep screen modes,
cover settings, and the updated custom image setup.
## Additional Context
* The sleep directoy entry while browsing files was distracting.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _NO_
jpirnay