Files
crosspoint-reader-mod/lib/KOReaderSync/ChapterXPathIndexer.h
cottongin 3628d8eb37 feat: port upstream KOReader sync PRs (#1185, #1217, #1090)
Port three unmerged upstream PRs with adaptations for the fork's
callback-based ActivityWithSubactivity architecture:

- PR #1185: Cache KOReader document hash using mtime fingerprint +
  file size validation to avoid repeated MD5 computation on sync.
- PR #1217: Proper KOReader XPath synchronisation via new
  ChapterXPathIndexer (Expat-based on-demand XHTML parsing) with
  XPath-first mapping and percentage fallback in ProgressMapper.
- PR #1090: Push Progress & Sleep menu option with PUSH_ONLY sync
  mode. Adapted to fork's callback pattern with deferFinish() for
  thread-safe completion. Modified to sleep silently on any failure
  (hash, upload, no credentials) rather than returning to reader.

Made-with: Cursor
2026-03-02 05:19:14 -05:00

68 lines
2.5 KiB
C++

#pragma once
#include <Epub.h>
#include <memory>
#include <string>
/**
* Lightweight XPath/progress bridge for KOReader sync.
*
* Why this exists:
* - CrossPoint stores reading position as chapter/page.
* - KOReader sync uses XPath + percentage.
*
* This utility reparses exactly one spine XHTML item with Expat and builds
* transient text anchors (<xpath, textOffset>) so we can translate in both
* directions without keeping a full DOM in memory.
*
* Design constraints (ESP32-C3):
* - No persistent full-book structures.
* - Parse-on-demand and free memory immediately.
* - Keep fallback behavior deterministic if parsing/matching fails.
*/
class ChapterXPathIndexer {
public:
/**
* Convert an intra-spine progress ratio to the nearest element-level XPath.
*
* @param epub Loaded EPUB instance
* @param spineIndex Current spine item index
* @param intraSpineProgress Position within the spine item [0.0, 1.0]
* @return Best matching XPath for KOReader, or empty string on failure
*/
static std::string findXPathForProgress(const std::shared_ptr<Epub>& epub, int spineIndex, float intraSpineProgress);
/**
* Resolve a KOReader XPath to an intra-spine progress ratio.
*
* Matching strategy:
* 1) exact anchor path match,
* 2) index-insensitive path match,
* 3) ancestor fallback.
*
* @param epub Loaded EPUB instance
* @param spineIndex Spine item index to parse
* @param xpath Incoming KOReader XPath
* @param outIntraSpineProgress Resolved position within spine [0.0, 1.0]
* @param outExactMatch True only for full exact path match
* @return true if any match was resolved; false means caller should fallback
*/
static bool findProgressForXPath(const std::shared_ptr<Epub>& epub, int spineIndex, const std::string& xpath,
float& outIntraSpineProgress, bool& outExactMatch);
/**
* Parse DocFragment index from KOReader-style path segment:
* /body/DocFragment[N]/body/...
*
* KOReader uses 1-based DocFragment indices; N is converted to the 0-based
* spine index stored in outSpineIndex (i.e. outSpineIndex = N - 1).
*
* @param xpath KOReader XPath
* @param outSpineIndex 0-based spine index derived from DocFragment[N]
* @return true when DocFragment[N] exists and N is a valid integer >= 1
* (converted to 0-based outSpineIndex); false otherwise
*/
static bool tryExtractSpineIndexFromXPath(const std::string& xpath, int& outSpineIndex);
};