feat: Add percent selection feature for jumping within the book

src/activities/reader/EpubReaderActivity.cpp

@@ -5,12 +5,14 @@
 #include <GfxRenderer.h>
 #include <SDCardManager.h>
 
+
 #include "CrossPointSettings.h"
 #include "CrossPointState.h"
 #include "EpubReaderChapterSelectionActivity.h"
 #include "MappedInputManager.h"
 #include "RecentBooksStore.h"
 #include "ScreenComponents.h"
+#include "activities/reader/EpubReaderPercentSelectionActivity.h"
 #include "fontIds.h"
 
 namespace {
@@ -22,6 +24,17 @@ constexpr int progressBarMarginTop = 1;
 
 }  // namespace
 
+// Clamp any percent-like value into the valid 0-100 range.
+static int clampPercent(const int value) {
+  if (value < 0) {
+    return 0;
+  }
+  if (value > 100) {
+    return 100;
+  }
+  return value;
+}
+
 void EpubReaderActivity::taskTrampoline(void* param) {
   auto* self = static_cast<EpubReaderActivity*>(param);
   self->displayTaskLoop();
@@ -123,7 +136,19 @@ void EpubReaderActivity::loop() {
     return;
   }
 
-  // Enter chapter selection activity
+  // Enter reader menu activity (suppressed after slider confirm/cancel).
+  if (suppressMenuOpenOnce) {
+    // If we're seeing the confirm release that closed the slider, consume it and return.
+    if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
+      suppressMenuOpenOnce = false;
+      return;
+    }
+    // If confirm is no longer pressed and no release is pending, clear suppression.
+    if (!mappedInput.isPressed(MappedInputManager::Button::Confirm)) {
+      suppressMenuOpenOnce = false;
+    }
+  }
+
   if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
     // Don't start activity transition while rendering
     xSemaphoreTake(renderingMutex, portMAX_DELAY);
@@ -225,6 +250,85 @@ void EpubReaderActivity::onReaderMenuBack() {
   updateRequired = true;
 }
 
+// Translate an absolute percent into a spine index plus a normalized position
+// within that spine so we can jump after the section is loaded.
+void EpubReaderActivity::jumpToPercent(int percent) {
+  if (!epub) {
+    return;
+  }
+
+  const size_t bookSize = epub->getBookSize();
+  if (bookSize == 0) {
+    return;
+  }
+
+  // Normalize input to 0-100 to avoid invalid jumps.
+  percent = clampPercent(percent);
+
+  // Convert percent into a byte-like absolute position across the spine sizes.
+  size_t targetSize = (bookSize * static_cast<size_t>(percent)) / 100;
+  if (percent >= 100 && bookSize > 0) {
+    // Ensure the final percent lands inside the last spine item.
+    targetSize = bookSize - 1;
+  }
+
+  const int spineCount = epub->getSpineItemsCount();
+  if (spineCount == 0) {
+    return;
+  }
+
+  int targetSpineIndex = spineCount - 1;
+  size_t prevCumulative = 0;
+
+  for (int i = 0; i < spineCount; i++) {
+    const size_t cumulative = epub->getCumulativeSpineItemSize(i);
+    if (targetSize <= cumulative) {
+      // Found the spine item containing the absolute position.
+      targetSpineIndex = i;
+      prevCumulative = (i > 0) ? epub->getCumulativeSpineItemSize(i - 1) : 0;
+      break;
+    }
+  }
+
+  const size_t cumulative = epub->getCumulativeSpineItemSize(targetSpineIndex);
+  const size_t spineSize = (cumulative > prevCumulative) ? (cumulative - prevCumulative) : 0;
+  // Store a normalized position within the spine so it can be applied once loaded.
+  pendingSpineProgress = (spineSize == 0) ? 0.0f
+                                          : static_cast<float>(targetSize - prevCumulative) /
+                                                static_cast<float>(spineSize);
+  if (pendingSpineProgress < 0.0f) {
+    pendingSpineProgress = 0.0f;
+  } else if (pendingSpineProgress > 1.0f) {
+    pendingSpineProgress = 1.0f;
+  }
+
+  // Reset state so renderScreen() reloads and repositions on the target spine.
+  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  currentSpineIndex = targetSpineIndex;
+  nextPageNumber = 0;
+  pendingPercentJump = true;
+  section.reset();
+  xSemaphoreGive(renderingMutex);
+}
+
+// Compute the overall reading position as a percent of the book.
+int EpubReaderActivity::getCurrentPercent() const {
+  if (!epub || epub->getBookSize() == 0) {
+    return 0;
+  }
+
+  // Estimate within-spine progress based on the current page.
+  float chapterProgress = 0.0f;
+  if (section && section->pageCount > 0) {
+    chapterProgress = static_cast<float>(section->currentPage) / static_cast<float>(section->pageCount);
+  }
+
+  // Convert to overall progress using cumulative spine sizes.
+  const float progress = epub->calculateProgress(currentSpineIndex, chapterProgress);
+  const int percent = static_cast<int>(progress * 100.0f + 0.5f);
+  return clampPercent(percent);
+}
+
 void EpubReaderActivity::onReaderMenuConfirm(EpubReaderMenuActivity::MenuAction action) {
   switch (action) {
     case EpubReaderMenuActivity::MenuAction::SELECT_CHAPTER: {
@@ -268,6 +372,29 @@ void EpubReaderActivity::onReaderMenuConfirm(EpubReaderMenuActivity::MenuAction
       xSemaphoreGive(renderingMutex);
       break;
     }
+    case EpubReaderMenuActivity::MenuAction::GO_TO_PERCENT: {
+      // Launch the slider-based percent selector and return here on confirm/cancel.
+      const int initialPercent = getCurrentPercent();
+      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      exitActivity();
+      enterNewActivity(new EpubReaderPercentSelectionActivity(
+          renderer, mappedInput, initialPercent,
+          [this](const int percent) {
+            // Apply the new position and exit back to the reader.
+            jumpToPercent(percent);
+            suppressMenuOpenOnce = true;
+            exitActivity();
+            updateRequired = true;
+          },
+          [this]() {
+            // Cancel selection and return to the reader.
+            suppressMenuOpenOnce = true;
+            exitActivity();
+            updateRequired = true;
+          }));
+      xSemaphoreGive(renderingMutex);
+      break;
+    }
     case EpubReaderMenuActivity::MenuAction::GO_HOME: {
       // 2. Trigger the reader's "Go Home" callback
       if (onGoHome) {
@@ -398,6 +525,18 @@ void EpubReaderActivity::renderScreen() {
       }
       cachedChapterTotalPageCount = 0;  // resets to 0 to prevent reading cached progress again
     }
+
+    if (pendingPercentJump && section->pageCount > 0) {
+      // Apply the pending percent jump now that we know the new section's page count.
+      int newPage = static_cast<int>(pendingSpineProgress * static_cast<float>(section->pageCount));
+      if (newPage < 0) {
+        newPage = 0;
+      } else if (newPage >= section->pageCount) {
+        newPage = section->pageCount - 1;
+      }
+      section->currentPage = newPage;
+      pendingPercentJump = false;
+    }
   }
 
   renderer.clearScreen();

src/activities/reader/EpubReaderActivity.h

@@ -18,6 +18,13 @@ class EpubReaderActivity final : public ActivityWithSubactivity {
   int pagesUntilFullRefresh = 0;
   int cachedSpineIndex = 0;
   int cachedChapterTotalPageCount = 0;
+  // Signals that the next render should reposition within the newly loaded section
+  // based on a cross-book percentage jump.
+  bool pendingPercentJump = false;
+  // Normalized 0.0-1.0 progress within the target spine item, computed from book percentage.
+  float pendingSpineProgress = 0.0f;
+  // Prevents the reader menu from reopening due to the confirm button used to exit the slider.
+  bool suppressMenuOpenOnce = false;
   bool updateRequired = false;
   const std::function<void()> onGoBack;
   const std::function<void()> onGoHome;
@@ -29,6 +36,10 @@ class EpubReaderActivity final : public ActivityWithSubactivity {
                       int orientedMarginBottom, int orientedMarginLeft);
   void renderStatusBar(int orientedMarginRight, int orientedMarginBottom, int orientedMarginLeft) const;
   void saveProgress(int spineIndex, int currentPage, int pageCount);
+  // Jump to a percentage of the book (0-100), mapping it to spine and page.
+  void jumpToPercent(int percent);
+  // Compute the current reading position as an integer percent (0-100).
+  int getCurrentPercent() const;
   void onReaderMenuBack();
   void onReaderMenuConfirm(EpubReaderMenuActivity::MenuAction action);
 

src/activities/reader/EpubReaderMenuActivity.h

@@ -13,7 +13,8 @@
 
 class EpubReaderMenuActivity final : public ActivityWithSubactivity {
  public:
-  enum class MenuAction { SELECT_CHAPTER, GO_HOME, DELETE_CACHE };
+  // Menu actions available from the reader menu.
+  enum class MenuAction { SELECT_CHAPTER, GO_TO_PERCENT, GO_HOME, DELETE_CACHE };
 
   explicit EpubReaderMenuActivity(GfxRenderer& renderer, MappedInputManager& mappedInput, const std::string& title,
                                   const std::function<void()>& onBack, const std::function<void(MenuAction)>& onAction)
@@ -32,7 +33,9 @@ class EpubReaderMenuActivity final : public ActivityWithSubactivity {
     std::string label;
   };
 
+  // Fixed menu layout (order matters for up/down navigation).
   const std::vector<MenuItem> menuItems = {{MenuAction::SELECT_CHAPTER, "Go to Chapter"},
+                                           {MenuAction::GO_TO_PERCENT, "Go to %"},
                                            {MenuAction::GO_HOME, "Go Home"},
                                            {MenuAction::DELETE_CACHE, "Delete Book Cache"}};
 

src/activities/reader/EpubReaderPercentSelectionActivity.cpp

@@ -0,0 +1,138 @@
+#include "EpubReaderPercentSelectionActivity.h"
+
+#include <GfxRenderer.h>
+
+#include "MappedInputManager.h"
+#include "fontIds.h"
+
+namespace {
+// Fine/coarse slider step sizes for percent adjustments.
+constexpr int kSmallStep = 1;
+constexpr int kLargeStep = 10;
+}
+
+void EpubReaderPercentSelectionActivity::onEnter() {
+  ActivityWithSubactivity::onEnter();
+  // Set up rendering task and mark first frame dirty.
+  renderingMutex = xSemaphoreCreateMutex();
+  updateRequired = true;
+  xTaskCreate(&EpubReaderPercentSelectionActivity::taskTrampoline, "EpubPercentSlider", 4096, this, 1,
+              &displayTaskHandle);
+}
+
+void EpubReaderPercentSelectionActivity::onExit() {
+  ActivityWithSubactivity::onExit();
+  // Ensure the render task is stopped before freeing the mutex.
+  xSemaphoreTake(renderingMutex, portMAX_DELAY);
+  if (displayTaskHandle) {
+    vTaskDelete(displayTaskHandle);
+    displayTaskHandle = nullptr;
+  }
+  vSemaphoreDelete(renderingMutex);
+  renderingMutex = nullptr;
+}
+
+void EpubReaderPercentSelectionActivity::taskTrampoline(void* param) {
+  auto* self = static_cast<EpubReaderPercentSelectionActivity*>(param);
+  self->displayTaskLoop();
+}
+
+void EpubReaderPercentSelectionActivity::displayTaskLoop() {
+  while (true) {
+    // Render only when the view is dirty and no subactivity is running.
+    if (updateRequired && !subActivity) {
+      updateRequired = false;
+      xSemaphoreTake(renderingMutex, portMAX_DELAY);
+      renderScreen();
+      xSemaphoreGive(renderingMutex);
+    }
+    vTaskDelay(10 / portTICK_PERIOD_MS);
+  }
+}
+
+void EpubReaderPercentSelectionActivity::adjustPercent(const int delta) {
+  // Apply delta and clamp within 0-100.
+  percent += delta;
+  if (percent < 0) {
+    percent = 0;
+  } else if (percent > 100) {
+    percent = 100;
+  }
+  updateRequired = true;
+}
+
+void EpubReaderPercentSelectionActivity::loop() {
+  if (subActivity) {
+    subActivity->loop();
+    return;
+  }
+
+  // Back cancels, confirm selects, arrows adjust the percent.
+  if (mappedInput.wasReleased(MappedInputManager::Button::Back)) {
+    onCancel();
+    return;
+  }
+
+  if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
+    onSelect(percent);
+    return;
+  }
+
+  if (mappedInput.wasReleased(MappedInputManager::Button::Left)) {
+    adjustPercent(-kSmallStep);
+    return;
+  }
+
+  if (mappedInput.wasReleased(MappedInputManager::Button::Right)) {
+    adjustPercent(kSmallStep);
+    return;
+  }
+
+  if (mappedInput.wasReleased(MappedInputManager::Button::Up)) {
+    adjustPercent(kLargeStep);
+    return;
+  }
+
+  if (mappedInput.wasReleased(MappedInputManager::Button::Down)) {
+    adjustPercent(-kLargeStep);
+    return;
+  }
+}
+
+void EpubReaderPercentSelectionActivity::renderScreen() {
+  renderer.clearScreen();
+
+  // Title and numeric percent value.
+  renderer.drawCenteredText(UI_12_FONT_ID, 15, "Go to Position", true, EpdFontFamily::BOLD);
+
+  const std::string percentText = std::to_string(percent) + "%";
+  renderer.drawCenteredText(UI_12_FONT_ID, 70, percentText.c_str(), true, EpdFontFamily::BOLD);
+
+  // Draw slider track.
+  const int screenWidth = renderer.getScreenWidth();
+  constexpr int barWidth = 360;
+  constexpr int barHeight = 16;
+  const int barX = (screenWidth - barWidth) / 2;
+  const int barY = 120;
+
+  renderer.drawRect(barX, barY, barWidth, barHeight);
+
+  // Fill slider based on percent.
+  const int fillWidth = (barWidth - 4) * percent / 100;
+  if (fillWidth > 0) {
+    renderer.fillRect(barX + 2, barY + 2, fillWidth, barHeight - 4);
+  }
+
+  // Draw a simple knob centered at the current percent.
+  const int knobX = barX + 2 + fillWidth - 2;
+  renderer.fillRect(knobX, barY - 4, 4, barHeight + 8, true);
+
+  // Hint text for step sizes.
+  renderer.drawCenteredText(SMALL_FONT_ID, barY + 30, "Left/Right: 1%  Up/Down: 10%", true);
+
+  // Button hints follow the current front button layout.
+  const auto labels = mappedInput.mapLabels("« Back", "Select", "-", "+");
+  renderer.drawButtonHints(UI_10_FONT_ID, labels.btn1, labels.btn2, labels.btn3, labels.btn4);
+
+  renderer.displayBuffer();
+}

src/activities/reader/EpubReaderPercentSelectionActivity.h

@@ -0,0 +1,46 @@
+#pragma once
+#include <freertos/FreeRTOS.h>
+#include <freertos/semphr.h>
+#include <freertos/task.h>
+
+#include <functional>
+
+#include "activities/ActivityWithSubactivity.h"
+#include "MappedInputManager.h"
+
+class EpubReaderPercentSelectionActivity final : public ActivityWithSubactivity {
+ public:
+  // Slider-style percent selector for jumping within a book.
+  explicit EpubReaderPercentSelectionActivity(GfxRenderer& renderer, MappedInputManager& mappedInput,
+                                              const int initialPercent, const std::function<void(int)>& onSelect,
+                                              const std::function<void()>& onCancel)
+      : ActivityWithSubactivity("EpubReaderPercentSelection", renderer, mappedInput),
+        percent(initialPercent),
+        onSelect(onSelect),
+        onCancel(onCancel) {}
+
+  void onEnter() override;
+  void onExit() override;
+  void loop() override;
+
+ private:
+    // Current percent value (0-100) shown on the slider.
+  int percent = 0;
+    // Render dirty flag for the task loop.
+  bool updateRequired = false;
+    // FreeRTOS task and mutex for rendering.
+  TaskHandle_t displayTaskHandle = nullptr;
+  SemaphoreHandle_t renderingMutex = nullptr;
+
+    // Callback invoked when the user confirms a percent.
+  const std::function<void(int)> onSelect;
+    // Callback invoked when the user cancels the slider.
+  const std::function<void()> onCancel;
+
+  static void taskTrampoline(void* param);
+  [[noreturn]] void displayTaskLoop();
+  // Render the slider UI.
+  void renderScreen();
+  // Change the current percent by a delta and clamp within bounds.
+  void adjustPercent(int delta);
+};