fix: Re-apply upstream PRs #1005, #1010, #1003

Re-applies changes that were accidentally discarded during a prior
dry-run cherry-pick reset (git checkout -- .).

- PR #1005: Use HalPowerManager for battery percentage (uint16_t return
  type, remove Battery.h, update theme files)
- PR #1010: Fix dangling pointer in onGoToReader()
- PR #1003: Render image placeholders while waiting for decode (adds
  isCached, renderPlaceholder, renderTextOnly, countUncachedImages,
  renderImagePlaceholders)

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/Epub/Epub/Page.cpp

@@ -61,6 +61,49 @@ std::unique_ptr<PageImage> PageImage::deserialize(FsFile& file) {
   return std::unique_ptr<PageImage>(new PageImage(std::move(ib), xPos, yPos));
 }
 
+bool PageImage::isCached() const { return imageBlock->isCached(); }
+
+void PageImage::renderPlaceholder(GfxRenderer& renderer, const int xOffset, const int yOffset) const {
+  int x = xPos + xOffset;
+  int y = yPos + yOffset;
+  int w = imageBlock->getWidth();
+  int h = imageBlock->getHeight();
+  renderer.fillRect(x, y, w, h, true);
+  if (w > 2 && h > 2) {
+    renderer.fillRect(x + 1, y + 1, w - 2, h - 2, false);
+  }
+}
+
+void Page::renderTextOnly(GfxRenderer& renderer, const int fontId, const int xOffset, const int yOffset) const {
+  for (auto& element : elements) {
+    if (element->getTag() == TAG_PageLine) {
+      element->render(renderer, fontId, xOffset, yOffset);
+    }
+  }
+}
+
+int Page::countUncachedImages() const {
+  int count = 0;
+  for (auto& element : elements) {
+    if (element->getTag() == TAG_PageImage) {
+      auto* img = static_cast<PageImage*>(element.get());
+      if (!img->isCached()) {
+        count++;
+      }
+    }
+  }
+  return count;
+}
+
+void Page::renderImagePlaceholders(GfxRenderer& renderer, const int xOffset, const int yOffset) const {
+  for (auto& element : elements) {
+    if (element->getTag() == TAG_PageImage) {
+      auto* img = static_cast<PageImage*>(element.get());
+      img->renderPlaceholder(renderer, xOffset, yOffset);
+    }
+  }
+}
+
 // ---------------------------------------------------------------------------
 // PageTableRow
 // ---------------------------------------------------------------------------

lib/Epub/Epub/Page.h

@@ -80,6 +80,8 @@ class PageImage final : public PageElement {
   void render(GfxRenderer& renderer, int fontId, int xOffset, int yOffset) override;
   bool serialize(FsFile& file) override;
   PageElementTag getTag() const override { return TAG_PageImage; }
+  bool isCached() const;
+  void renderPlaceholder(GfxRenderer& renderer, int xOffset, int yOffset) const;
   static std::unique_ptr<PageImage> deserialize(FsFile& file);
 
   // Helper to get image block dimensions (needed for bounding box calculation)
@@ -104,4 +106,8 @@ class Page {
   // Returns true if page has images and fills out the bounding box coordinates.
   // If no images, returns false.
   bool getImageBoundingBox(int& outX, int& outY, int& outWidth, int& outHeight) const;
+
+  void renderTextOnly(GfxRenderer& renderer, int fontId, int xOffset, int yOffset) const;
+  int countUncachedImages() const;
+  void renderImagePlaceholders(GfxRenderer& renderer, int xOffset, int yOffset) const;
 };

lib/Epub/Epub/blocks/ImageBlock.cpp

@@ -93,6 +93,11 @@ bool renderFromCache(GfxRenderer& renderer, const std::string& cachePath, int x,
 
 }  // namespace
 
+bool ImageBlock::isCached() const {
+  std::string cachePath = getCachePath(imagePath);
+  return Storage.exists(cachePath.c_str());
+}
+
 void ImageBlock::render(GfxRenderer& renderer, const int x, const int y) {
   LOG_DBG("IMG", "Rendering image at %d,%d: %s (%dx%d)", x, y, imagePath.c_str(), width, height);
 

lib/Epub/Epub/blocks/ImageBlock.h

@@ -16,6 +16,7 @@ class ImageBlock final : public Block {
   int16_t getHeight() const { return height; }
 
   bool imageExists() const;
+  bool isCached() const;
 
   BlockType getType() override { return IMAGE_BLOCK; }
   bool isEmpty() override { return false; }

lib/hal/HalPowerManager.cpp

@@ -78,7 +78,7 @@ void HalPowerManager::startDeepSleep(HalGPIO& gpio) const {
   esp_deep_sleep_start();
 }
 
-int HalPowerManager::getBatteryPercentage() const {
+uint16_t HalPowerManager::getBatteryPercentage() const {
   static const BatteryMonitor battery = BatteryMonitor(BAT_GPIO0);
   return battery.readPercentage();
 }

lib/hal/HalPowerManager.h

@@ -28,7 +28,7 @@ class HalPowerManager {
   void startDeepSleep(HalGPIO& gpio) const;
 
   // Get battery percentage (range 0-100)
-  int getBatteryPercentage() const;
+  uint16_t getBatteryPercentage() const;
 
   // RAII lock to prevent low-power mode during critical work (e.g. rendering)
   class Lock {

src/Battery.h

@@ -1,6 +0,0 @@
-#pragma once
-#include <BatteryMonitor.h>
-
-#define BAT_GPIO0 0  // Battery voltage
-
-static BatteryMonitor battery(BAT_GPIO0);

src/activities/home/HomeActivity.cpp

@@ -13,7 +13,6 @@
 #include <cstring>
 #include <vector>
 
-#include "Battery.h"
 #include "CrossPointSettings.h"
 #include "CrossPointState.h"
 #include "MappedInputManager.h"

src/activities/reader/EpubReaderActivity.cpp

@@ -1020,6 +1020,14 @@ void EpubReaderActivity::renderContents(std::unique_ptr<Page> page, const int or
   // Force special handling for pages with images when anti-aliasing is on
   bool imagePageWithAA = page->hasImages() && SETTINGS.textAntiAliasing;
 
+  if (page->countUncachedImages() > 0) {
+    page->renderTextOnly(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop);
+    page->renderImagePlaceholders(renderer, orientedMarginLeft, orientedMarginTop);
+    renderStatusBar(orientedMarginRight, orientedMarginBottom, orientedMarginLeft);
+    renderer.displayBuffer();
+    renderer.clearScreen();
+  }
+
   page->render(renderer, SETTINGS.getReaderFontId(), orientedMarginLeft, orientedMarginTop);
 
   // Draw bookmark ribbon indicator in top-right corner if current page is bookmarked

src/components/themes/BaseTheme.cpp

@@ -1,6 +1,7 @@
 #include "BaseTheme.h"
 
 #include <GfxRenderer.h>
+#include <HalPowerManager.h>
 #include <HalStorage.h>
 #include <Logging.h>
 #include <Utf8.h>
@@ -9,7 +10,6 @@
 #include <ctime>
 #include <string>
 
-#include "Battery.h"
 #include "CrossPointSettings.h"
 #include "I18n.h"
 #include "RecentBooksStore.h"
@@ -49,7 +49,7 @@ void drawBatteryIcon(const GfxRenderer& renderer, int x, int y, int battWidth, i
 
 void BaseTheme::drawBatteryLeft(const GfxRenderer& renderer, Rect rect, const bool showPercentage) const {
   // Left aligned: icon on left, percentage on right (reader mode)
-  const uint16_t percentage = battery.readPercentage();
+  const uint16_t percentage = powerManager.getBatteryPercentage();
   const int y = rect.y + 6;
 
   if (showPercentage) {
@@ -64,7 +64,7 @@ void BaseTheme::drawBatteryLeft(const GfxRenderer& renderer, Rect rect, const bo
 void BaseTheme::drawBatteryRight(const GfxRenderer& renderer, Rect rect, const bool showPercentage) const {
   // Right aligned: percentage on left, icon on right (UI headers)
   // rect.x is already positioned for the icon (drawHeader calculated it)
-  const uint16_t percentage = battery.readPercentage();
+  const uint16_t percentage = powerManager.getBatteryPercentage();
   const int y = rect.y + 6;
 
   if (showPercentage) {

src/components/themes/lyra/LyraTheme.cpp

@@ -1,6 +1,7 @@
 #include "LyraTheme.h"
 
 #include <GfxRenderer.h>
+#include <HalPowerManager.h>
 #include <HalStorage.h>
 #include <I18n.h>
 #include <Utf8.h>
@@ -10,7 +11,6 @@
 #include <string>
 #include <vector>
 
-#include "Battery.h"
 #include "CrossPointSettings.h"
 #include "RecentBooksStore.h"
 #include "components/UITheme.h"
@@ -88,7 +88,7 @@ const uint8_t* iconForName(UIIcon icon, int size) {
 
 void LyraTheme::drawBatteryLeft(const GfxRenderer& renderer, Rect rect, const bool showPercentage) const {
   // Left aligned: icon on left, percentage on right (reader mode)
-  const uint16_t percentage = battery.readPercentage();
+  const uint16_t percentage = powerManager.getBatteryPercentage();
   const int y = rect.y + 6;
   const int battWidth = LyraMetrics::values.batteryWidth;
 
@@ -125,7 +125,7 @@ void LyraTheme::drawBatteryLeft(const GfxRenderer& renderer, Rect rect, const bo
 
 void LyraTheme::drawBatteryRight(const GfxRenderer& renderer, Rect rect, const bool showPercentage) const {
   // Right aligned: percentage on left, icon on right (UI headers)
-  const uint16_t percentage = battery.readPercentage();
+  const uint16_t percentage = powerManager.getBatteryPercentage();
   const int y = rect.y + 6;
   const int battWidth = LyraMetrics::values.batteryWidth;
 

src/main.cpp

@@ -15,7 +15,6 @@
 #include <cstring>
 #include <ctime>
 
-#include "Battery.h"
 #include "CrossPointSettings.h"
 #include "CrossPointState.h"
 #include "KOReaderCredentialStore.h"
@@ -227,9 +226,9 @@ void onGoHome();
 void onGoToMyLibraryWithPath(const std::string& path);
 void onGoToRecentBooks();
 void onGoToReader(const std::string& initialEpubPath) {
+  const std::string bookPath = initialEpubPath;  // Copy before exitActivity() invalidates the reference
   exitActivity();
-  enterNewActivity(
-      new ReaderActivity(renderer, mappedInputManager, initialEpubPath, onGoHome, onGoToMyLibraryWithPath));
+  enterNewActivity(new ReaderActivity(renderer, mappedInputManager, bookPath, onGoHome, onGoToMyLibraryWithPath));
 }
 
 void onGoToFileTransfer() {