Xteink-X4-crosspoint-reader/lib/KOReaderSync/KOReaderDocumentId.cpp
Carson Hicks dfd7b615dc
fix: Fix KOReader document md5 calculation for binary matching progress sync (#529)
## Summary

* **What is the goal of this PR?**
Resolve [KoSync progress does not sync between Crosspoint-reader and
KOReader
(Kindle)](https://github.com/crosspoint-reader/crosspoint-reader/issues/502)

* **What changes are included?**
KOReaderDocumentId::getOffset() - Update the value for the md5 offset
calculation to match KOReader.

## Additional Context

I've tested this with a couple of my ebooks and binary matching with
KOReader sync seems to be working fine now for both pushing and pulling
progress.

---

### 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**_
2026-01-27 22:14:07 +11:00

97 lines
2.5 KiB
C++

#include "KOReaderDocumentId.h"
#include <HardwareSerial.h>
#include <MD5Builder.h>
#include <SDCardManager.h>
namespace {
// Extract filename from path (everything after last '/')
std::string getFilename(const std::string& path) {
const size_t pos = path.rfind('/');
if (pos == std::string::npos) {
return path;
}
return path.substr(pos + 1);
}
} // namespace
std::string KOReaderDocumentId::calculateFromFilename(const std::string& filePath) {
const std::string filename = getFilename(filePath);
if (filename.empty()) {
return "";
}
MD5Builder md5;
md5.begin();
md5.add(filename.c_str());
md5.calculate();
std::string result = md5.toString().c_str();
Serial.printf("[%lu] [KODoc] Filename hash: %s (from '%s')\n", millis(), result.c_str(), filename.c_str());
return result;
}
size_t KOReaderDocumentId::getOffset(int i) {
// Offset = 1024 << (2*i)
// For i = -1: KOReader uses a value of 0
// For i >= 0: 1024 << (2*i)
if (i < 0) {
return 0;
}
return CHUNK_SIZE << (2 * i);
}
std::string KOReaderDocumentId::calculate(const std::string& filePath) {
FsFile file;
if (!SdMan.openFileForRead("KODoc", filePath, file)) {
Serial.printf("[%lu] [KODoc] Failed to open file: %s\n", millis(), filePath.c_str());
return "";
}
const size_t fileSize = file.fileSize();
Serial.printf("[%lu] [KODoc] Calculating hash for file: %s (size: %zu)\n", millis(), filePath.c_str(), fileSize);
// Initialize MD5 builder
MD5Builder md5;
md5.begin();
// Buffer for reading chunks
uint8_t buffer[CHUNK_SIZE];
size_t totalBytesRead = 0;
// Read from each offset (i = -1 to 10)
for (int i = -1; i < OFFSET_COUNT - 1; i++) {
const size_t offset = getOffset(i);
// Skip if offset is beyond file size
if (offset >= fileSize) {
continue;
}
// Seek to offset
if (!file.seekSet(offset)) {
Serial.printf("[%lu] [KODoc] Failed to seek to offset %zu\n", millis(), offset);
continue;
}
// Read up to CHUNK_SIZE bytes
const size_t bytesToRead = std::min(CHUNK_SIZE, fileSize - offset);
const size_t bytesRead = file.read(buffer, bytesToRead);
if (bytesRead > 0) {
md5.add(buffer, bytesRead);
totalBytesRead += bytesRead;
}
}
file.close();
// Calculate final hash
md5.calculate();
std::string result = md5.toString().c_str();
Serial.printf("[%lu] [KODoc] Hash calculated: %s (from %zu bytes)\n", millis(), result.c_str(), totalBytesRead);
return result;
}