Enhance TOC parsing and chapter selection logic

- Update .gitignore to include additional paths
- Refactor Epub::parseContentOpf to improve NCX item retrieval
- Modify ContentOpfParser to store media type in ManifestItem
- Implement rebuildVisibleSpineIndices in EpubReaderChapterSelectionScreen for better chapter navigation
- Adjust rendering logic to handle empty chapter lists gracefully

.gitignore

@@ -1,3 +1,5 @@
 .pio
 .idea
 .DS_Store
+.vscode
+lib/EpdFont/fontsrc

lib/Epub/Epub.cpp

@@ -69,16 +69,31 @@ bool Epub::parseContentOpf(const std::string& contentOpfFilePath) {
 
   // Grab data from opfParser into epub
   title = opfParser.title;
+  constexpr const char* NCX_MEDIA_TYPE = "application/x-dtbncx+xml";
 
+  for (const auto& [id, manifestItem] : opfParser.items) {
+    (void)id;
+    if (manifestItem.mediaType == NCX_MEDIA_TYPE) {
+      tocNcxItem = manifestItem.href;
+      break;
+    }
+  }
+
+  if (tocNcxItem.empty() && !opfParser.tocNcxPath.empty()) {
+    tocNcxItem = opfParser.tocNcxPath;
+  }
+
+  if (tocNcxItem.empty()) {
     if (opfParser.items.count("ncx")) {
-    tocNcxItem = opfParser.items.at("ncx");
+      tocNcxItem = opfParser.items.at("ncx").href;
     } else if (opfParser.items.count("ncxtoc")) {
-    tocNcxItem = opfParser.items.at("ncxtoc");
+      tocNcxItem = opfParser.items.at("ncxtoc").href;
+    }
   }
 
   for (auto& spineRef : opfParser.spineRefs) {
     if (opfParser.items.count(spineRef)) {
-      spine.emplace_back(spineRef, opfParser.items.at(spineRef));
+      spine.emplace_back(spineRef, opfParser.items.at(spineRef).href);
     }
   }
 

lib/Epub/Epub/parsers/ContentOpfParser.cpp

@@ -96,17 +96,24 @@ void XMLCALL ContentOpfParser::startElement(void* userData, const XML_Char* name
 
   if (self->state == IN_MANIFEST && (strcmp(name, "item") == 0 || strcmp(name, "opf:item") == 0)) {
     std::string itemId;
-    std::string href;
+    ManifestItem item;
 
     for (int i = 0; atts[i]; i += 2) {
       if (strcmp(atts[i], "id") == 0) {
         itemId = atts[i + 1];
       } else if (strcmp(atts[i], "href") == 0) {
-        href = self->baseContentPath + atts[i + 1];
+        item.href = self->baseContentPath + atts[i + 1];
+      } else if (strcmp(atts[i], "media-type") == 0) {
+        item.mediaType = atts[i + 1];
       }
     }
 
-    self->items[itemId] = href;
+    if (!itemId.empty()) {
+      self->items[itemId] = item;
+      if (item.mediaType == "application/x-dtbncx+xml" && self->tocNcxPath.empty()) {
+        self->tocNcxPath = item.href;
+      }
+    }
     return;
   }
 

lib/Epub/Epub/parsers/ContentOpfParser.h

@@ -2,6 +2,8 @@
 #include <Print.h>
 
 #include <map>
+#include <string>
+#include <vector>
 
 #include "Epub.h"
 #include "expat.h"
@@ -26,9 +28,14 @@ class ContentOpfParser final : public Print {
   static void endElement(void* userData, const XML_Char* name);
 
  public:
+  struct ManifestItem {
+    std::string href;
+    std::string mediaType;
+  };
+
   std::string title;
   std::string tocNcxPath;
-  std::map<std::string, std::string> items;
+  std::map<std::string, ManifestItem> items;
   std::vector<std::string> spineRefs;
 
   explicit ContentOpfParser(const std::string& baseContentPath, const size_t xmlSize)

src/screens/EpubReaderChapterSelectionScreen.cpp

@@ -13,13 +13,41 @@ void EpubReaderChapterSelectionScreen::taskTrampoline(void* param) {
   self->displayTaskLoop();
 }
 
+void EpubReaderChapterSelectionScreen::rebuildVisibleSpineIndices() {
+  visibleSpineIndices.clear();
+  if (!epub) {
+    return;
+  }
+
+  const int spineCount = epub->getSpineItemsCount();
+  visibleSpineIndices.reserve(spineCount);
+  for (int i = 0; i < spineCount; i++) {
+    if (epub->getTocIndexForSpineIndex(i) != -1) {
+      visibleSpineIndices.push_back(i);
+    }
+  }
+}
+
 void EpubReaderChapterSelectionScreen::onEnter() {
   if (!epub) {
     return;
   }
 
   renderingMutex = xSemaphoreCreateMutex();
-  selectorIndex = currentSpineIndex;
+  rebuildVisibleSpineIndices();
+
+  selectorIndex = 0;
+  if (!visibleSpineIndices.empty()) {
+    for (size_t i = 0; i < visibleSpineIndices.size(); i++) {
+      if (visibleSpineIndices[i] == currentSpineIndex) {
+        selectorIndex = static_cast<int>(i);
+        break;
+      }
+    }
+    if (selectorIndex >= static_cast<int>(visibleSpineIndices.size())) {
+      selectorIndex = static_cast<int>(visibleSpineIndices.size()) - 1;
+    }
+  }
 
   // Trigger first update
   updateRequired = true;
@@ -40,6 +68,7 @@ void EpubReaderChapterSelectionScreen::onExit() {
   }
   vSemaphoreDelete(renderingMutex);
   renderingMutex = nullptr;
+  visibleSpineIndices.clear();
 }
 
 void EpubReaderChapterSelectionScreen::handleInput() {
@@ -51,22 +80,53 @@ void EpubReaderChapterSelectionScreen::handleInput() {
   const bool skipPage = inputManager.getHeldTime() > SKIP_PAGE_MS;
 
   if (inputManager.wasPressed(InputManager::BTN_CONFIRM)) {
-    onSelectSpineIndex(selectorIndex);
-  } else if (inputManager.wasPressed(InputManager::BTN_BACK)) {
+    if (!visibleSpineIndices.empty()) {
+      if (selectorIndex >= static_cast<int>(visibleSpineIndices.size())) {
+        selectorIndex = static_cast<int>(visibleSpineIndices.size()) - 1;
+      }
+      onSelectSpineIndex(visibleSpineIndices[selectorIndex]);
+    }
+    return;
+  }
+
+  if (inputManager.wasPressed(InputManager::BTN_BACK)) {
     onGoBack();
-  } else if (prevReleased) {
+    return;
+  }
+
+  const int chapterCount = static_cast<int>(visibleSpineIndices.size());
+  if (chapterCount == 0) {
+    return;
+  }
+
+  if (selectorIndex >= chapterCount) {
+    selectorIndex = chapterCount - 1;
+  }
+
+  if (prevReleased) {
     if (skipPage) {
-      selectorIndex =
-          ((selectorIndex / PAGE_ITEMS - 1) * PAGE_ITEMS + epub->getSpineItemsCount()) % epub->getSpineItemsCount();
+      const int totalPages = (chapterCount + PAGE_ITEMS - 1) / PAGE_ITEMS;
+      int currentPage = selectorIndex / PAGE_ITEMS;
+      currentPage = (currentPage + totalPages - 1) % totalPages;
+      selectorIndex = currentPage * PAGE_ITEMS;
+      if (selectorIndex >= chapterCount) {
+        selectorIndex = chapterCount - 1;
+      }
     } else {
-      selectorIndex = (selectorIndex + epub->getSpineItemsCount() - 1) % epub->getSpineItemsCount();
+      selectorIndex = (selectorIndex + chapterCount - 1) % chapterCount;
     }
     updateRequired = true;
   } else if (nextReleased) {
     if (skipPage) {
-      selectorIndex = ((selectorIndex / PAGE_ITEMS + 1) * PAGE_ITEMS) % epub->getSpineItemsCount();
+      const int totalPages = (chapterCount + PAGE_ITEMS - 1) / PAGE_ITEMS;
+      int currentPage = selectorIndex / PAGE_ITEMS;
+      currentPage = (currentPage + 1) % totalPages;
+      selectorIndex = currentPage * PAGE_ITEMS;
+      if (selectorIndex >= chapterCount) {
+        selectorIndex = chapterCount - 1;
+      }
     } else {
-      selectorIndex = (selectorIndex + 1) % epub->getSpineItemsCount();
+      selectorIndex = (selectorIndex + 1) % chapterCount;
     }
     updateRequired = true;
   }
@@ -90,18 +150,29 @@ void EpubReaderChapterSelectionScreen::renderScreen() {
   const auto pageWidth = renderer.getScreenWidth();
   renderer.drawCenteredText(READER_FONT_ID, 10, "Select Chapter", true, BOLD);
 
+  const int chapterCount = static_cast<int>(visibleSpineIndices.size());
+  if (chapterCount == 0) {
+    renderer.drawText(UI_FONT_ID, 20, 60, "No chapters available");
+    renderer.displayBuffer();
+    return;
+  }
+
+  if (selectorIndex >= chapterCount) {
+    selectorIndex = chapterCount - 1;
+  }
+
   const auto pageStartIndex = selectorIndex / PAGE_ITEMS * PAGE_ITEMS;
   renderer.fillRect(0, 60 + (selectorIndex % PAGE_ITEMS) * 30 + 2, pageWidth - 1, 30);
-  for (int i = pageStartIndex; i < epub->getSpineItemsCount() && i < pageStartIndex + PAGE_ITEMS; i++) {
-    const int tocIndex = epub->getTocIndexForSpineIndex(i);
+  for (int i = pageStartIndex; i < chapterCount && i < pageStartIndex + PAGE_ITEMS; i++) {
+    const int spineIndex = visibleSpineIndices[i];
+    const int tocIndex = epub->getTocIndexForSpineIndex(spineIndex);
     if (tocIndex == -1) {
-      renderer.drawText(UI_FONT_ID, 20, 60 + (i % PAGE_ITEMS) * 30, "Unnamed", i != selectorIndex);
-    } else {
+      continue;  // Filtered chapters should not reach here, but skip defensively.
+    }
     auto item = epub->getTocItem(tocIndex);
     renderer.drawText(UI_FONT_ID, 20 + (item.level - 1) * 15, 60 + (i % PAGE_ITEMS) * 30, item.title.c_str(),
                       i != selectorIndex);
   }
-  }
 
   renderer.displayBuffer();
 }

src/screens/EpubReaderChapterSelectionScreen.h

@@ -5,6 +5,7 @@
 #include <freertos/task.h>
 
 #include <memory>
+#include <vector>
 
 #include "Screen.h"
 
@@ -15,11 +16,13 @@ class EpubReaderChapterSelectionScreen final : public Screen {
   int currentSpineIndex = 0;
   int selectorIndex = 0;
   bool updateRequired = false;
+  std::vector<int> visibleSpineIndices;
   const std::function<void()> onGoBack;
   const std::function<void(int newSpineIndex)> onSelectSpineIndex;
 
   static void taskTrampoline(void* param);
   [[noreturn]] void displayTaskLoop();
+  void rebuildVisibleSpineIndices();
   void renderScreen();
 
  public: