Amend button behaviour

src/CrossPointSettings.h

@@ -287,8 +287,9 @@ class CrossPointSettings {
     BTN_PREV_SECTION,
     BTN_EXIT_READER,
     BTN_READER_MENU,
-    BTN_KOREADER_SYNC,
     BTN_TOGGLE_BIONIC_READING,
+    BTN_KOREADER_SYNC,
+    BTN_CYCLE_FONT_SIZE,
     BUTTON_ACTION_COUNT
   };
 

src/SettingsList.h

@@ -140,13 +140,14 @@ inline const std::vector<SettingInfo> list = {
 // All entries share the same ordered action-label list; the submenu groups them behind
 // a single placeholder row in the device UI.
 // Shared action options (everything except the first "default" entry).
-#define BTN_ACT_OPTIONS                                                                                     \
-  StrId::STR_BTN_ACT_PAGE_FORWARD, StrId::STR_BTN_ACT_PAGE_BACK, StrId::STR_BTN_ACT_PAGE_FORWARD_10,        \
-      StrId::STR_BTN_ACT_PAGE_BACK_10, StrId::STR_BTN_ACT_GO_HOME, StrId::STR_BTN_ACT_SLEEP,                \
-      StrId::STR_BTN_ACT_FORCE_REFRESH, StrId::STR_BTN_ACT_FORCE_FAST_REFRESH, StrId::STR_BTN_ACT_OPEN_TOC, \
-      StrId::STR_BTN_ACT_OPEN_BOOKMARKS, StrId::STR_BTN_ACT_STAR_PAGE, StrId::STR_BTN_ACT_FOOTNOTES,        \
-      StrId::STR_BTN_ACT_NEXT_SECTION, StrId::STR_BTN_ACT_PREV_SECTION, StrId::STR_BTN_ACT_EXIT_READER,     \
-      StrId::STR_BTN_ACT_READER_MENU, StrId::STR_BTN_ACT_TOGGLE_BIONIC_READING, StrId::STR_BTN_ACT_KOREADER_SYNC
+#define BTN_ACT_OPTIONS                                                                                           \
+  StrId::STR_BTN_ACT_PAGE_FORWARD, StrId::STR_BTN_ACT_PAGE_BACK, StrId::STR_BTN_ACT_PAGE_FORWARD_10,              \
+      StrId::STR_BTN_ACT_PAGE_BACK_10, StrId::STR_BTN_ACT_GO_HOME, StrId::STR_BTN_ACT_SLEEP,                      \
+      StrId::STR_BTN_ACT_FORCE_REFRESH, StrId::STR_BTN_ACT_FORCE_FAST_REFRESH, StrId::STR_BTN_ACT_OPEN_TOC,       \
+      StrId::STR_BTN_ACT_OPEN_BOOKMARKS, StrId::STR_BTN_ACT_STAR_PAGE, StrId::STR_BTN_ACT_FOOTNOTES,              \
+      StrId::STR_BTN_ACT_NEXT_SECTION, StrId::STR_BTN_ACT_PREV_SECTION, StrId::STR_BTN_ACT_EXIT_READER,           \
+      StrId::STR_BTN_ACT_READER_MENU, StrId::STR_BTN_ACT_TOGGLE_BIONIC_READING, StrId::STR_BTN_ACT_KOREADER_SYNC, \
+      StrId::STR_BTN_ACT_CYCLE_FONT_SIZE
 
     // Back button: short=exit reader, double=ignore, long=go home
     SettingInfo::Enum(StrId::STR_BTN_SHORT_PRESS, &CrossPointSettings::btnShortBack, {StrId::STR_BTN_DEF_EXIT_READER},

src/activities/reader/EpubReaderActivity.cpp

@@ -2006,6 +2006,16 @@ void EpubReaderActivity::onButtonAction(const CrossPointSettings::BUTTON_ACTION
         requestUpdate();
       }
       break;
+    case BA::BTN_CYCLE_FONT_SIZE:
+      if (epub) {
+        const uint8_t current =
+            (bookFontSizeOverride >= 0) ? static_cast<uint8_t>(bookFontSizeOverride) : SETTINGS.fontSize;
+        const int8_t next = static_cast<int8_t>((current + 1) % CrossPointSettings::FONT_SIZE_COUNT);
+        applyBookReaderOverrides(bookEmbeddedStyleOverride, bookImageRenderingOverride, bookFontFamilyOverride,
+                                 bookSdFontFamilyOverride, next, bookBionicReadingOverride);
+        requestUpdate();
+      }
+      break;
     case BA::BTN_KOREADER_SYNC:
       launchKOReaderSync(SyncLaunchMode::COMPARE);
       break;

src/main.cpp

@@ -539,6 +539,12 @@ void loop() {
         case BA::BTN_KOREADER_SYNC:
           activityManager.dispatchButtonAction(BA::BTN_KOREADER_SYNC);
           break;
+        case BA::BTN_TOGGLE_BIONIC_READING:
+          activityManager.dispatchButtonAction(BA::BTN_TOGGLE_BIONIC_READING);
+          break;
+        case BA::BTN_CYCLE_FONT_SIZE:
+          activityManager.dispatchButtonAction(BA::BTN_CYCLE_FONT_SIZE);
+          break;
         default:
           break;
       }

src/util/ButtonNavigator.cpp

@@ -1,6 +1,7 @@
 #include "ButtonNavigator.h"
 
 #include "ButtonEventManager.h"
+#include "activities/ActivityManager.h"
 
 const MappedInputManager* ButtonNavigator::mappedInput = nullptr;
 
@@ -42,15 +43,25 @@ void ButtonNavigator::onPress(const Buttons& buttons, const Callback& callback)
 }
 
 void ButtonNavigator::onRelease(const Buttons& buttons, const Callback& callback) {
-  const bool wasReleased = std::any_of(buttons.begin(), buttons.end(), [](const MappedInputManager::Button button) {
-    if (mappedInput == nullptr || !mappedInput->wasReleased(button)) {
-      return false;
-    }
-
-    // If a button Short is still pending while we wait for a possible double,
-    // avoid firing release-based navigation first.
-    return !globalButtonEvents().isShortPending(button);
-  });
+  // The double-click FSM in ButtonEventManager delays Short events by DOUBLE_WINDOW_MS
+  // (300ms) when a double-press action is configured for that button, so the configured
+  // Short and Double actions can be disambiguated. In a reader activity that gating must
+  // suppress release-based navigation during the wait, otherwise Left/Right would both
+  // turn the page AND fire the configured short action.
+  //
+  // In non-reader UIs (settings, file browser, etc.), only navigation reacts to release —
+  // the configured per-button actions are not dispatched there (see
+  // ActivityManager::dispatchButtonAction, which is reader-only). Gating on isShortPending
+  // there just makes Left/Right navigation feel sluggish (300ms lag) compared to Up/Down
+  // (which have no FSM at all). So skip the gate outside reader activities.
+  const bool inReader = activityManager.isReaderActivity();
+  const bool wasReleased =
+      std::any_of(buttons.begin(), buttons.end(), [inReader](const MappedInputManager::Button button) {
+        if (mappedInput == nullptr || !mappedInput->wasReleased(button)) {
+          return false;
+        }
+        return !(inReader && globalButtonEvents().isShortPending(button));
+      });
 
   if (wasReleased) {
     if (lastContinuousNavTime == 0) {