Update open-x4-sdk

## Summary

* Accept big endian version in XTC files
* Recently, two issues
(https://github.com/daveallie/crosspoint-reader/issues/157 and
https://github.com/daveallie/crosspoint-reader/issues/146) have popped
up with XTC files with a big endian encoded version. This is read out as
256.
  * We should be more lax and accept these values.

lib/Epub/Epub.cpp

@@ -312,6 +312,11 @@ bool Epub::generateCoverBmp() const {
 }
 
 uint8_t* Epub::readItemContentsToBytes(const std::string& itemHref, size_t* size, const bool trailingNullByte) const {
+  if (itemHref.empty()) {
+    Serial.printf("[%lu] [EBP] Failed to read item, empty href\n", millis());
+    return nullptr;
+  }
+
   const std::string path = FsHelpers::normalisePath(itemHref);
 
   const auto content = ZipFile(filepath).readFileToMemory(path.c_str(), size, trailingNullByte);
@@ -324,6 +329,11 @@ uint8_t* Epub::readItemContentsToBytes(const std::string& itemHref, size_t* size
 }
 
 bool Epub::readItemContentsToStream(const std::string& itemHref, Print& out, const size_t chunkSize) const {
+  if (itemHref.empty()) {
+    Serial.printf("[%lu] [EBP] Failed to read item, empty href\n", millis());
+    return false;
+  }
+
   const std::string path = FsHelpers::normalisePath(itemHref);
   return ZipFile(filepath).readFileToStream(path.c_str(), out, chunkSize);
 }

lib/Epub/Epub/BookMetadataCache.cpp

@@ -85,12 +85,12 @@ bool BookMetadataCache::buildBookBin(const std::string& epubPath, const BookMeta
     return false;
   }
 
-  constexpr size_t headerASize =
-      sizeof(BOOK_CACHE_VERSION) + /* LUT Offset */ sizeof(size_t) + sizeof(spineCount) + sizeof(tocCount);
-  const size_t metadataSize =
+  constexpr uint32_t headerASize =
+      sizeof(BOOK_CACHE_VERSION) + /* LUT Offset */ sizeof(uint32_t) + sizeof(spineCount) + sizeof(tocCount);
+  const uint32_t metadataSize =
       metadata.title.size() + metadata.author.size() + metadata.coverItemHref.size() + sizeof(uint32_t) * 3;
-  const size_t lutSize = sizeof(size_t) * spineCount + sizeof(size_t) * tocCount;
-  const size_t lutOffset = headerASize + metadataSize;
+  const uint32_t lutSize = sizeof(uint32_t) * spineCount + sizeof(uint32_t) * tocCount;
+  const uint32_t lutOffset = headerASize + metadataSize;
 
   // Header A
   serialization::writePod(bookFile, BOOK_CACHE_VERSION);
@@ -105,7 +105,7 @@ bool BookMetadataCache::buildBookBin(const std::string& epubPath, const BookMeta
   // Loop through spine entries, writing LUT positions
   spineFile.seek(0);
   for (int i = 0; i < spineCount; i++) {
-    auto pos = spineFile.position();
+    uint32_t pos = spineFile.position();
     auto spineEntry = readSpineEntry(spineFile);
     serialization::writePod(bookFile, pos + lutOffset + lutSize);
   }
@@ -113,9 +113,9 @@ bool BookMetadataCache::buildBookBin(const std::string& epubPath, const BookMeta
   // Loop through toc entries, writing LUT positions
   tocFile.seek(0);
   for (int i = 0; i < tocCount; i++) {
-    auto pos = tocFile.position();
+    uint32_t pos = tocFile.position();
     auto tocEntry = readTocEntry(tocFile);
-    serialization::writePod(bookFile, pos + lutOffset + lutSize + spineFile.position());
+    serialization::writePod(bookFile, pos + lutOffset + lutSize + static_cast<uint32_t>(spineFile.position()));
   }
 
   // LUTs complete
@@ -141,7 +141,7 @@ bool BookMetadataCache::buildBookBin(const std::string& epubPath, const BookMeta
     zip.close();
     return false;
   }
-  size_t cumSize = 0;
+  uint32_t cumSize = 0;
   spineFile.seek(0);
   for (int i = 0; i < spineCount; i++) {
     auto spineEntry = readSpineEntry(spineFile);
@@ -203,16 +203,16 @@ bool BookMetadataCache::cleanupTmpFiles() const {
   return true;
 }
 
-size_t BookMetadataCache::writeSpineEntry(FsFile& file, const SpineEntry& entry) const {
-  const auto pos = file.position();
+uint32_t BookMetadataCache::writeSpineEntry(FsFile& file, const SpineEntry& entry) const {
+  const uint32_t pos = file.position();
   serialization::writeString(file, entry.href);
   serialization::writePod(file, entry.cumulativeSize);
   serialization::writePod(file, entry.tocIndex);
   return pos;
 }
 
-size_t BookMetadataCache::writeTocEntry(FsFile& file, const TocEntry& entry) const {
-  const auto pos = file.position();
+uint32_t BookMetadataCache::writeTocEntry(FsFile& file, const TocEntry& entry) const {
+  const uint32_t pos = file.position();
   serialization::writeString(file, entry.title);
   serialization::writeString(file, entry.href);
   serialization::writeString(file, entry.anchor);
@@ -303,8 +303,8 @@ BookMetadataCache::SpineEntry BookMetadataCache::getSpineEntry(const int index)
   }
 
   // Seek to spine LUT item, read from LUT and get out data
-  bookFile.seek(lutOffset + sizeof(size_t) * index);
-  size_t spineEntryPos;
+  bookFile.seek(lutOffset + sizeof(uint32_t) * index);
+  uint32_t spineEntryPos;
   serialization::readPod(bookFile, spineEntryPos);
   bookFile.seek(spineEntryPos);
   return readSpineEntry(bookFile);
@@ -322,8 +322,8 @@ BookMetadataCache::TocEntry BookMetadataCache::getTocEntry(const int index) {
   }
 
   // Seek to TOC LUT item, read from LUT and get out data
-  bookFile.seek(lutOffset + sizeof(size_t) * spineCount + sizeof(size_t) * index);
-  size_t tocEntryPos;
+  bookFile.seek(lutOffset + sizeof(uint32_t) * spineCount + sizeof(uint32_t) * index);
+  uint32_t tocEntryPos;
   serialization::readPod(bookFile, tocEntryPos);
   bookFile.seek(tocEntryPos);
   return readTocEntry(bookFile);

lib/Epub/Epub/BookMetadataCache.h

@@ -51,8 +51,8 @@ class BookMetadataCache {
   FsFile spineFile;
   FsFile tocFile;
 
-  size_t writeSpineEntry(FsFile& file, const SpineEntry& entry) const;
-  size_t writeTocEntry(FsFile& file, const TocEntry& entry) const;
+  uint32_t writeSpineEntry(FsFile& file, const SpineEntry& entry) const;
+  uint32_t writeTocEntry(FsFile& file, const TocEntry& entry) const;
   SpineEntry readSpineEntry(FsFile& file) const;
   TocEntry readTocEntry(FsFile& file) const;
 

lib/Epub/Epub/Section.cpp

@@ -8,17 +8,17 @@
 
 namespace {
 constexpr uint8_t SECTION_FILE_VERSION = 7;
-constexpr size_t HEADER_SIZE = sizeof(uint8_t) + sizeof(int) + sizeof(float) + sizeof(bool) + sizeof(int) +
-                               sizeof(int) + sizeof(int) + sizeof(size_t);
+constexpr uint32_t HEADER_SIZE = sizeof(uint8_t) + sizeof(int) + sizeof(float) + sizeof(bool) + sizeof(int) +
+                                 sizeof(int) + sizeof(int) + sizeof(uint32_t);
 }  // namespace
 
-size_t Section::onPageComplete(std::unique_ptr<Page> page) {
+uint32_t Section::onPageComplete(std::unique_ptr<Page> page) {
   if (!file) {
     Serial.printf("[%lu] [SCT] File not open for writing page %d\n", millis(), pageCount);
     return 0;
   }
 
-  const auto position = file.position();
+  const uint32_t position = file.position();
   if (!page->serialize(file)) {
     Serial.printf("[%lu] [SCT] Failed to serialize page %d\n", millis(), pageCount);
     return 0;
@@ -37,7 +37,7 @@ void Section::writeSectionFileHeader(const int fontId, const float lineCompressi
   }
   static_assert(HEADER_SIZE == sizeof(SECTION_FILE_VERSION) + sizeof(fontId) + sizeof(lineCompression) +
                                    sizeof(extraParagraphSpacing) + sizeof(viewportWidth) + sizeof(viewportHeight) +
-                                   sizeof(pageCount) + sizeof(size_t),
+                                   sizeof(pageCount) + sizeof(uint32_t),
                 "Header size mismatch");
   serialization::writePod(file, SECTION_FILE_VERSION);
   serialization::writePod(file, fontId);
@@ -46,7 +46,7 @@ void Section::writeSectionFileHeader(const int fontId, const float lineCompressi
   serialization::writePod(file, viewportWidth);
   serialization::writePod(file, viewportHeight);
   serialization::writePod(file, pageCount);  // Placeholder for page count (will be initially 0 when written)
-  serialization::writePod(file, static_cast<size_t>(0));  // Placeholder for LUT offset
+  serialization::writePod(file, static_cast<uint32_t>(0));  // Placeholder for LUT offset
 }
 
 bool Section::loadSectionFile(const int fontId, const float lineCompression, const bool extraParagraphSpacing,
@@ -111,13 +111,19 @@ bool Section::createSectionFile(const int fontId, const float lineCompression, c
                                 const int viewportWidth, const int viewportHeight,
                                 const std::function<void()>& progressSetupFn,
                                 const std::function<void(int)>& progressFn) {
-  constexpr size_t MIN_SIZE_FOR_PROGRESS = 50 * 1024;  // 50KB
+  constexpr uint32_t MIN_SIZE_FOR_PROGRESS = 50 * 1024;  // 50KB
   const auto localPath = epub->getSpineItem(spineIndex).href;
   const auto tmpHtmlPath = epub->getCachePath() + "/.tmp_" + std::to_string(spineIndex) + ".html";
 
+  // Create cache directory if it doesn't exist
+  {
+    const auto sectionsDir = epub->getCachePath() + "/sections";
+    SdMan.mkdir(sectionsDir.c_str());
+  }
+
   // Retry logic for SD card timing issues
   bool success = false;
-  size_t fileSize = 0;
+  uint32_t fileSize = 0;
   for (int attempt = 0; attempt < 3 && !success; attempt++) {
     if (attempt > 0) {
       Serial.printf("[%lu] [SCT] Retrying stream (attempt %d)...\n", millis(), attempt + 1);
@@ -160,7 +166,7 @@ bool Section::createSectionFile(const int fontId, const float lineCompression, c
     return false;
   }
   writeSectionFileHeader(fontId, lineCompression, extraParagraphSpacing, viewportWidth, viewportHeight);
-  std::vector<size_t> lut = {};
+  std::vector<uint32_t> lut = {};
 
   ChapterHtmlSlimParser visitor(
       tmpHtmlPath, renderer, fontId, lineCompression, extraParagraphSpacing, viewportWidth, viewportHeight,
@@ -176,10 +182,10 @@ bool Section::createSectionFile(const int fontId, const float lineCompression, c
     return false;
   }
 
-  const auto lutOffset = file.position();
+  const uint32_t lutOffset = file.position();
   bool hasFailedLutRecords = false;
   // Write LUT
-  for (const auto& pos : lut) {
+  for (const uint32_t& pos : lut) {
     if (pos == 0) {
       hasFailedLutRecords = true;
       break;
@@ -195,7 +201,7 @@ bool Section::createSectionFile(const int fontId, const float lineCompression, c
   }
 
   // Go back and write LUT offset
-  file.seek(HEADER_SIZE - sizeof(size_t) - sizeof(pageCount));
+  file.seek(HEADER_SIZE - sizeof(uint32_t) - sizeof(pageCount));
   serialization::writePod(file, pageCount);
   serialization::writePod(file, lutOffset);
   file.close();
@@ -207,11 +213,11 @@ std::unique_ptr<Page> Section::loadPageFromSectionFile() {
     return nullptr;
   }
 
-  file.seek(HEADER_SIZE - sizeof(size_t));
-  size_t lutOffset;
+  file.seek(HEADER_SIZE - sizeof(uint32_t));
+  uint32_t lutOffset;
   serialization::readPod(file, lutOffset);
-  file.seek(lutOffset + sizeof(size_t) * currentPage);
-  size_t pagePos;
+  file.seek(lutOffset + sizeof(uint32_t) * currentPage);
+  uint32_t pagePos;
   serialization::readPod(file, pagePos);
   file.seek(pagePos);
 

lib/Epub/Epub/Section.h

@@ -16,7 +16,7 @@ class Section {
 
   void writeSectionFileHeader(int fontId, float lineCompression, bool extraParagraphSpacing, int viewportWidth,
                               int viewportHeight);
-  size_t onPageComplete(std::unique_ptr<Page> page);
+  uint32_t onPageComplete(std::unique_ptr<Page> page);
 
  public:
   int pageCount = 0;

lib/Xtc/Xtc.cpp

@@ -87,6 +87,21 @@ std::string Xtc::getTitle() const {
   return filepath.substr(lastSlash, lastDot - lastSlash);
 }
 
+bool Xtc::hasChapters() const {
+  if (!loaded || !parser) {
+    return false;
+  }
+  return parser->hasChapters();
+}
+
+const std::vector<xtc::ChapterInfo>& Xtc::getChapters() const {
+  static const std::vector<xtc::ChapterInfo> kEmpty;
+  if (!loaded || !parser) {
+    return kEmpty;
+  }
+  return parser->getChapters();
+}
+
 std::string Xtc::getCoverBmpPath() const { return cachePath + "/cover.bmp"; }
 
 bool Xtc::generateCoverBmp() const {

lib/Xtc/Xtc.h

@@ -9,6 +9,7 @@
 
 #include <memory>
 #include <string>
+#include <vector>
 
 #include "Xtc/XtcParser.h"
 #include "Xtc/XtcTypes.h"
@@ -55,6 +56,8 @@ class Xtc {
 
   // Metadata
   std::string getTitle() const;
+  bool hasChapters() const;
+  const std::vector<xtc::ChapterInfo>& getChapters() const;
 
   // Cover image support (for sleep screen)
   std::string getCoverBmpPath() const;

lib/Xtc/Xtc/XtcParser.cpp

@@ -20,6 +20,7 @@ XtcParser::XtcParser()
       m_defaultWidth(DISPLAY_WIDTH),
       m_defaultHeight(DISPLAY_HEIGHT),
       m_bitDepth(1),
+      m_hasChapters(false),
       m_lastError(XtcError::OK) {
   memset(&m_header, 0, sizeof(m_header));
 }
@@ -57,6 +58,14 @@ XtcError XtcParser::open(const char* filepath) {
     return m_lastError;
   }
 
+  // Read chapters if present
+  m_lastError = readChapters();
+  if (m_lastError != XtcError::OK) {
+    Serial.printf("[%lu] [XTC] Failed to read chapters: %s\n", millis(), errorToString(m_lastError));
+    m_file.close();
+    return m_lastError;
+  }
+
   m_isOpen = true;
   Serial.printf("[%lu] [XTC] Opened file: %s (%u pages, %dx%d)\n", millis(), filepath, m_header.pageCount,
                 m_defaultWidth, m_defaultHeight);
@@ -69,7 +78,9 @@ void XtcParser::close() {
     m_isOpen = false;
   }
   m_pageTable.clear();
+  m_chapters.clear();
   m_title.clear();
+  m_hasChapters = false;
   memset(&m_header, 0, sizeof(m_header));
 }
 
@@ -91,7 +102,9 @@ XtcError XtcParser::readHeader() {
   m_bitDepth = (m_header.magic == XTCH_MAGIC) ? 2 : 1;
 
   // Check version
-  if (m_header.version > 1) {
+  // Currently, version 1 is the only valid version, however some generators are using big endian for the version code
+  // so we also accept version 256 (0x0100)
+  if (m_header.version != 1 && m_header.version != 256) {
     Serial.printf("[%lu] [XTC] Unsupported version: %d\n", millis(), m_header.version);
     return XtcError::INVALID_VERSION;
   }
@@ -166,6 +179,112 @@ XtcError XtcParser::readPageTable() {
   return XtcError::OK;
 }
 
+XtcError XtcParser::readChapters() {
+  m_hasChapters = false;
+  m_chapters.clear();
+
+  uint8_t hasChaptersFlag = 0;
+  if (!m_file.seek(0x0B)) {
+    return XtcError::READ_ERROR;
+  }
+  if (m_file.read(&hasChaptersFlag, sizeof(hasChaptersFlag)) != sizeof(hasChaptersFlag)) {
+    return XtcError::READ_ERROR;
+  }
+
+  if (hasChaptersFlag != 1) {
+    return XtcError::OK;
+  }
+
+  uint64_t chapterOffset = 0;
+  if (!m_file.seek(0x30)) {
+    return XtcError::READ_ERROR;
+  }
+  if (m_file.read(reinterpret_cast<uint8_t*>(&chapterOffset), sizeof(chapterOffset)) != sizeof(chapterOffset)) {
+    return XtcError::READ_ERROR;
+  }
+
+  if (chapterOffset == 0) {
+    return XtcError::OK;
+  }
+
+  const uint64_t fileSize = m_file.size();
+  if (chapterOffset < sizeof(XtcHeader) || chapterOffset >= fileSize || chapterOffset + 96 > fileSize) {
+    return XtcError::OK;
+  }
+
+  uint64_t maxOffset = 0;
+  if (m_header.pageTableOffset > chapterOffset) {
+    maxOffset = m_header.pageTableOffset;
+  } else if (m_header.dataOffset > chapterOffset) {
+    maxOffset = m_header.dataOffset;
+  } else {
+    maxOffset = fileSize;
+  }
+
+  if (maxOffset <= chapterOffset) {
+    return XtcError::OK;
+  }
+
+  constexpr size_t chapterSize = 96;
+  const uint64_t available = maxOffset - chapterOffset;
+  const size_t chapterCount = static_cast<size_t>(available / chapterSize);
+  if (chapterCount == 0) {
+    return XtcError::OK;
+  }
+
+  if (!m_file.seek(chapterOffset)) {
+    return XtcError::READ_ERROR;
+  }
+
+  std::vector<uint8_t> chapterBuf(chapterSize);
+  for (size_t i = 0; i < chapterCount; i++) {
+    if (m_file.read(chapterBuf.data(), chapterSize) != chapterSize) {
+      return XtcError::READ_ERROR;
+    }
+
+    char nameBuf[81];
+    memcpy(nameBuf, chapterBuf.data(), 80);
+    nameBuf[80] = '\0';
+    const size_t nameLen = strnlen(nameBuf, 80);
+    std::string name(nameBuf, nameLen);
+
+    uint16_t startPage = 0;
+    uint16_t endPage = 0;
+    memcpy(&startPage, chapterBuf.data() + 0x50, sizeof(startPage));
+    memcpy(&endPage, chapterBuf.data() + 0x52, sizeof(endPage));
+
+    if (name.empty() && startPage == 0 && endPage == 0) {
+      break;
+    }
+
+    if (startPage > 0) {
+      startPage--;
+    }
+    if (endPage > 0) {
+      endPage--;
+    }
+
+    if (startPage >= m_header.pageCount) {
+      continue;
+    }
+
+    if (endPage >= m_header.pageCount) {
+      endPage = m_header.pageCount - 1;
+    }
+
+    if (startPage > endPage) {
+      continue;
+    }
+
+    ChapterInfo chapter{std::move(name), startPage, endPage};
+    m_chapters.push_back(std::move(chapter));
+  }
+
+  m_hasChapters = !m_chapters.empty();
+  Serial.printf("[%lu] [XTC] Chapters: %u\n", millis(), static_cast<unsigned int>(m_chapters.size()));
+  return XtcError::OK;
+}
+
 bool XtcParser::getPageInfo(uint32_t pageIndex, PageInfo& info) const {
   if (pageIndex >= m_pageTable.size()) {
     return false;

lib/Xtc/Xtc/XtcParser.h

@@ -70,6 +70,9 @@ class XtcParser {
   // Get title from metadata
   std::string getTitle() const { return m_title; }
 
+  bool hasChapters() const { return m_hasChapters; }
+  const std::vector<ChapterInfo>& getChapters() const { return m_chapters; }
+
   // Validation
   static bool isValidXtcFile(const char* filepath);
 
@@ -81,16 +84,19 @@ class XtcParser {
   bool m_isOpen;
   XtcHeader m_header;
   std::vector<PageInfo> m_pageTable;
+  std::vector<ChapterInfo> m_chapters;
   std::string m_title;
   uint16_t m_defaultWidth;
   uint16_t m_defaultHeight;
   uint8_t m_bitDepth;  // 1 = XTC/XTG (1-bit), 2 = XTCH/XTH (2-bit)
+  bool m_hasChapters;
   XtcError m_lastError;
 
   // Internal helper functions
   XtcError readHeader();
   XtcError readPageTable();
   XtcError readTitle();
+  XtcError readChapters();
 };
 
 }  // namespace xtc

lib/Xtc/Xtc/XtcTypes.h

@@ -13,6 +13,7 @@
 #pragma once
 
 #include <cstdint>
+#include <string>
 
 namespace xtc {
 
@@ -92,6 +93,12 @@ struct PageInfo {
   uint8_t padding;   // Alignment padding
 };  // 16 bytes total
 
+struct ChapterInfo {
+  std::string name;
+  uint16_t startPage;
+  uint16_t endPage;
+};
+
 // Error codes
 enum class XtcError {
   OK = 0,

open-x4-sdk

@@ -1 +1 @@
-Subproject commit 0d269feed2d6450a8a9149fd333c5336ca25daf2
+Subproject commit bd4e6707503ab9c97d13ee0d8f8c69e9ff03cd12

src/CrossPointSettings.h

@@ -59,7 +59,7 @@ class CrossPointSettings {
   // Get singleton instance
   static CrossPointSettings& getInstance() { return instance; }
 
-  uint16_t getPowerButtonDuration() const { return shortPwrBtn ? 10 : 500; }
+  uint16_t getPowerButtonDuration() const { return shortPwrBtn ? 10 : 400; }
 
   bool saveToFile() const;
   bool loadFromFile();

src/MappedInputManager.cpp

@@ -1,5 +1,7 @@
 #include "MappedInputManager.h"
 
+#include "CrossPointSettings.h"
+
 decltype(InputManager::BTN_BACK) MappedInputManager::mapButton(const Button button) const {
   const auto frontLayout = static_cast<CrossPointSettings::FRONT_BUTTON_LAYOUT>(SETTINGS.frontButtonLayout);
   const auto sideLayout = static_cast<CrossPointSettings::SIDE_BUTTON_LAYOUT>(SETTINGS.sideButtonLayout);

src/MappedInputManager.h

@@ -2,8 +2,6 @@
 
 #include <InputManager.h>
 
-#include "CrossPointSettings.h"
-
 class MappedInputManager {
  public:
   enum class Button { Back, Confirm, Left, Right, Up, Down, Power, PageBack, PageForward };

src/activities/home/HomeActivity.cpp

@@ -122,12 +122,16 @@ void HomeActivity::render() const {
     if (bookName.length() > 5 && bookName.substr(bookName.length() - 5) == ".epub") {
       bookName.resize(bookName.length() - 5);
     }
+
     // Truncate if too long
-    if (bookName.length() > 25) {
-      bookName.resize(22);
-      bookName += "...";
-    }
     std::string continueLabel = "Continue: " + bookName;
+    int itemWidth = renderer.getTextWidth(UI_FONT_ID, continueLabel.c_str());
+    while (itemWidth > renderer.getScreenWidth() - 40 && continueLabel.length() > 8) {
+      continueLabel.replace(continueLabel.length() - 5, 5, "...");
+      itemWidth = renderer.getTextWidth(UI_FONT_ID, continueLabel.c_str());
+      Serial.printf("[%lu] [HOM] width: %lu, pageWidth: %lu\n", millis(), itemWidth, pageWidth);
+    }
+
     renderer.drawText(UI_FONT_ID, 20, menuY, continueLabel.c_str(), selectorIndex != menuIndex);
     menuY += 30;
     menuIndex++;

src/activities/reader/XtcReaderActivity.cpp

@@ -13,6 +13,7 @@
 
 #include "CrossPointState.h"
 #include "MappedInputManager.h"
+#include "XtcReaderChapterSelectionActivity.h"
 #include "config.h"
 
 namespace {
@@ -27,7 +28,7 @@ void XtcReaderActivity::taskTrampoline(void* param) {
 }
 
 void XtcReaderActivity::onEnter() {
-  Activity::onEnter();
+  ActivityWithSubactivity::onEnter();
 
   if (!xtc) {
     return;
@@ -56,7 +57,7 @@ void XtcReaderActivity::onEnter() {
 }
 
 void XtcReaderActivity::onExit() {
-  Activity::onExit();
+  ActivityWithSubactivity::onExit();
 
   // Wait until not rendering to delete task
   xSemaphoreTake(renderingMutex, portMAX_DELAY);
@@ -70,6 +71,32 @@ void XtcReaderActivity::onExit() {
 }
 
 void XtcReaderActivity::loop() {
+  // Pass input responsibility to sub activity if exists
+  if (subActivity) {
+    subActivity->loop();
+    return;
+  }
+
+  // Enter chapter selection activity
+  if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
+    if (xtc && xtc->hasChapters() && !xtc->getChapters().empty()) {
+      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      exitActivity();
+      enterNewActivity(new XtcReaderChapterSelectionActivity(
+          this->renderer, this->mappedInput, xtc, currentPage,
+          [this] {
+            exitActivity();
+            updateRequired = true;
+          },
+          [this](const uint32_t newPage) {
+            currentPage = newPage;
+            exitActivity();
+            updateRequired = true;
+          }));
+      xSemaphoreGive(renderingMutex);
+    }
+  }
+
   // Long press BACK (1s+) goes directly to home
   if (mappedInput.isPressed(MappedInputManager::Button::Back) && mappedInput.getHeldTime() >= goHomeMs) {
     onGoHome();

src/activities/reader/XtcReaderActivity.h

@@ -12,9 +12,9 @@
 #include <freertos/semphr.h>
 #include <freertos/task.h>
 
-#include "activities/Activity.h"
+#include "activities/ActivityWithSubactivity.h"
 
-class XtcReaderActivity final : public Activity {
+class XtcReaderActivity final : public ActivityWithSubactivity {
   std::shared_ptr<Xtc> xtc;
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
@@ -34,7 +34,10 @@ class XtcReaderActivity final : public Activity {
  public:
   explicit XtcReaderActivity(GfxRenderer& renderer, MappedInputManager& mappedInput, std::unique_ptr<Xtc> xtc,
                              const std::function<void()>& onGoBack, const std::function<void()>& onGoHome)
-      : Activity("XtcReader", renderer, mappedInput), xtc(std::move(xtc)), onGoBack(onGoBack), onGoHome(onGoHome) {}
+      : ActivityWithSubactivity("XtcReader", renderer, mappedInput),
+        xtc(std::move(xtc)),
+        onGoBack(onGoBack),
+        onGoHome(onGoHome) {}
   void onEnter() override;
   void onExit() override;
   void loop() override;

src/activities/reader/XtcReaderChapterSelectionActivity.cpp

@@ -0,0 +1,151 @@
+#include "XtcReaderChapterSelectionActivity.h"
+
+#include <GfxRenderer.h>
+
+#include "MappedInputManager.h"
+#include "config.h"
+
+namespace {
+constexpr int SKIP_PAGE_MS = 700;
+}  // namespace
+
+int XtcReaderChapterSelectionActivity::getPageItems() const {
+  constexpr int startY = 60;
+  constexpr int lineHeight = 30;
+
+  const int screenHeight = renderer.getScreenHeight();
+  const int availableHeight = screenHeight - startY;
+  int items = availableHeight / lineHeight;
+  if (items < 1) {
+    items = 1;
+  }
+  return items;
+}
+
+int XtcReaderChapterSelectionActivity::findChapterIndexForPage(uint32_t page) const {
+  if (!xtc) {
+    return 0;
+  }
+
+  const auto& chapters = xtc->getChapters();
+  for (size_t i = 0; i < chapters.size(); i++) {
+    if (page >= chapters[i].startPage && page <= chapters[i].endPage) {
+      return static_cast<int>(i);
+    }
+  }
+  return 0;
+}
+
+void XtcReaderChapterSelectionActivity::taskTrampoline(void* param) {
+  auto* self = static_cast<XtcReaderChapterSelectionActivity*>(param);
+  self->displayTaskLoop();
+}
+
+void XtcReaderChapterSelectionActivity::onEnter() {
+  Activity::onEnter();
+
+  if (!xtc) {
+    return;
+  }
+
+  renderingMutex = xSemaphoreCreateMutex();
+  selectorIndex = findChapterIndexForPage(currentPage);
+
+  updateRequired = true;
+  xTaskCreate(&XtcReaderChapterSelectionActivity::taskTrampoline, "XtcReaderChapterSelectionActivityTask",
+              4096,               // Stack size
+              this,               // Parameters
+              1,                  // Priority
+              &displayTaskHandle  // Task handle
+  );
+}
+
+void XtcReaderChapterSelectionActivity::onExit() {
+  Activity::onExit();
+
+  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  if (displayTaskHandle) {
+    vTaskDelete(displayTaskHandle);
+    displayTaskHandle = nullptr;
+  }
+  vSemaphoreDelete(renderingMutex);
+  renderingMutex = nullptr;
+}
+
+void XtcReaderChapterSelectionActivity::loop() {
+  const bool prevReleased = mappedInput.wasReleased(MappedInputManager::Button::Up) ||
+                            mappedInput.wasReleased(MappedInputManager::Button::Left);
+  const bool nextReleased = mappedInput.wasReleased(MappedInputManager::Button::Down) ||
+                            mappedInput.wasReleased(MappedInputManager::Button::Right);
+
+  const bool skipPage = mappedInput.getHeldTime() > SKIP_PAGE_MS;
+  const int pageItems = getPageItems();
+
+  if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
+    const auto& chapters = xtc->getChapters();
+    if (!chapters.empty() && selectorIndex >= 0 && selectorIndex < static_cast<int>(chapters.size())) {
+      onSelectPage(chapters[selectorIndex].startPage);
+    }
+  } else if (mappedInput.wasReleased(MappedInputManager::Button::Back)) {
+    onGoBack();
+  } else if (prevReleased) {
+    const int total = static_cast<int>(xtc->getChapters().size());
+    if (total == 0) {
+      return;
+    }
+    if (skipPage) {
+      selectorIndex = ((selectorIndex / pageItems - 1) * pageItems + total) % total;
+    } else {
+      selectorIndex = (selectorIndex + total - 1) % total;
+    }
+    updateRequired = true;
+  } else if (nextReleased) {
+    const int total = static_cast<int>(xtc->getChapters().size());
+    if (total == 0) {
+      return;
+    }
+    if (skipPage) {
+      selectorIndex = ((selectorIndex / pageItems + 1) * pageItems) % total;
+    } else {
+      selectorIndex = (selectorIndex + 1) % total;
+    }
+    updateRequired = true;
+  }
+}
+
+void XtcReaderChapterSelectionActivity::displayTaskLoop() {
+  while (true) {
+    if (updateRequired) {
+      updateRequired = false;
+      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      renderScreen();
+      xSemaphoreGive(renderingMutex);
+    }
+    vTaskDelay(10 / portTICK_PERIOD_MS);
+  }
+}
+
+void XtcReaderChapterSelectionActivity::renderScreen() {
+  renderer.clearScreen();
+
+  const auto pageWidth = renderer.getScreenWidth();
+  const int pageItems = getPageItems();
+  renderer.drawCenteredText(READER_FONT_ID, 10, "Select Chapter", true, BOLD);
+
+  const auto& chapters = xtc->getChapters();
+  if (chapters.empty()) {
+    renderer.drawCenteredText(UI_FONT_ID, 120, "No chapters", true, REGULAR);
+    renderer.displayBuffer();
+    return;
+  }
+
+  const auto pageStartIndex = selectorIndex / pageItems * pageItems;
+  renderer.fillRect(0, 60 + (selectorIndex % pageItems) * 30 - 2, pageWidth - 1, 30);
+  for (int i = pageStartIndex; i < static_cast<int>(chapters.size()) && i < pageStartIndex + pageItems; i++) {
+    const auto& chapter = chapters[i];
+    const char* title = chapter.name.empty() ? "Unnamed" : chapter.name.c_str();
+    renderer.drawText(UI_FONT_ID, 20, 60 + (i % pageItems) * 30, title, i != selectorIndex);
+  }
+
+  renderer.displayBuffer();
+}

src/activities/reader/XtcReaderChapterSelectionActivity.h

@@ -0,0 +1,41 @@
+#pragma once
+#include <Xtc.h>
+#include <freertos/FreeRTOS.h>
+#include <freertos/semphr.h>
+#include <freertos/task.h>
+
+#include <memory>
+
+#include "../Activity.h"
+
+class XtcReaderChapterSelectionActivity final : public Activity {
+  std::shared_ptr<Xtc> xtc;
+  TaskHandle_t displayTaskHandle = nullptr;
+  SemaphoreHandle_t renderingMutex = nullptr;
+  uint32_t currentPage = 0;
+  int selectorIndex = 0;
+  bool updateRequired = false;
+  const std::function<void()> onGoBack;
+  const std::function<void(uint32_t newPage)> onSelectPage;
+
+  int getPageItems() const;
+  int findChapterIndexForPage(uint32_t page) const;
+
+  static void taskTrampoline(void* param);
+  [[noreturn]] void displayTaskLoop();
+  void renderScreen();
+
+ public:
+  explicit XtcReaderChapterSelectionActivity(GfxRenderer& renderer, MappedInputManager& mappedInput,
+                                             const std::shared_ptr<Xtc>& xtc, uint32_t currentPage,
+                                             const std::function<void()>& onGoBack,
+                                             const std::function<void(uint32_t newPage)>& onSelectPage)
+      : Activity("XtcReaderChapterSelection", renderer, mappedInput),
+        xtc(xtc),
+        currentPage(currentPage),
+        onGoBack(onGoBack),
+        onSelectPage(onSelectPage) {}
+  void onEnter() override;
+  void onExit() override;
+  void loop() override;
+};

src/activities/settings/SettingsActivity.cpp

@@ -159,6 +159,9 @@ void SettingsActivity::render() const {
   // Draw header
   renderer.drawCenteredText(READER_FONT_ID, 10, "Settings", true, BOLD);
 
+  // Draw selection
+  renderer.fillRect(0, 60 + selectedSettingIndex * 30 - 2, pageWidth - 1, 30);
+
   // Draw all settings
   for (int i = 0; i < settingsCount; i++) {
     const int settingY = 60 + i * 30;  // 30 pixels between settings
@@ -169,18 +172,19 @@ void SettingsActivity::render() const {
     }
 
     // Draw setting name
-    renderer.drawText(UI_FONT_ID, 20, settingY, settingsList[i].name);
+    renderer.drawText(UI_FONT_ID, 20, settingY, settingsList[i].name, i != selectedSettingIndex);
 
     // Draw value based on setting type
+    std::string valueText = "";
     if (settingsList[i].type == SettingType::TOGGLE && settingsList[i].valuePtr != nullptr) {
       const bool value = SETTINGS.*(settingsList[i].valuePtr);
-      renderer.drawText(UI_FONT_ID, pageWidth - 80, settingY, value ? "ON" : "OFF");
+      valueText = value ? "ON" : "OFF";
     } else if (settingsList[i].type == SettingType::ENUM && settingsList[i].valuePtr != nullptr) {
       const uint8_t value = SETTINGS.*(settingsList[i].valuePtr);
-      auto valueText = settingsList[i].enumValues[value];
-      const auto width = renderer.getTextWidth(UI_FONT_ID, valueText.c_str());
-      renderer.drawText(UI_FONT_ID, pageWidth - 50 - width, settingY, valueText.c_str());
+      valueText = settingsList[i].enumValues[value];
     }
+    const auto width = renderer.getTextWidth(UI_FONT_ID, valueText.c_str());
+    renderer.drawText(UI_FONT_ID, pageWidth - 20 - width, settingY, valueText.c_str(), i != selectedSettingIndex);
   }
 
   // Draw version text above button hints

src/main.cpp

@@ -84,7 +84,7 @@ void verifyWakeupLongPress() {
   const auto start = millis();
   bool abort = false;
   // It takes us some time to wake up from deep sleep, so we need to subtract that from the duration
-  uint16_t calibration = 25;
+  uint16_t calibration = 29;
   uint16_t calibratedPressDuration =
       (calibration < SETTINGS.getPowerButtonDuration()) ? SETTINGS.getPowerButtonDuration() - calibration : 1;
 
@@ -179,8 +179,6 @@ void setup() {
     Serial.begin(115200);
   }
 
-  Serial.printf("[%lu] [   ] Starting CrossPoint version " CROSSPOINT_VERSION "\n", millis());
-
   inputManager.begin();
   // Initialize pins
   pinMode(BAT_GPIO0, INPUT);
@@ -203,6 +201,9 @@ void setup() {
   // verify power button press duration after we've read settings.
   verifyWakeupLongPress();
 
+  // First serial output only here to avoid timing inconsistencies for power button press duration verification
+  Serial.printf("[%lu] [   ] Starting CrossPoint version " CROSSPOINT_VERSION "\n", millis());
+
   setupDisplayAndFonts();
 
   exitActivity();