{

public:

static OnScreenKeyboardModule &instance();

void start(const char *header, const char *initialText, uint32_t durationMs,

std::function<void(const std::string &)> callback);

void stop(bool callEmptyCallback);

void handleInput(const InputEvent &event);

static bool processVirtualKeyboardInput(const InputEvent &event, VirtualKeyboard *keyboard);

bool draw(OLEDDisplay *display);

void showPopup(const char *title, const char *content, uint32_t durationMs);

void clearPopup();

// Draw only the popup overlay (used when legacy virtualKeyboard draws the keyboard)

void drawPopupOverlay(OLEDDisplay *display);

private:

OnScreenKeyboardModule() = default;

~OnScreenKeyboardModule();

OnScreenKeyboardModule(const OnScreenKeyboardModule &) = delete;

OnScreenKeyboardModule &operator=(const OnScreenKeyboardModule &) = delete;

void onSubmit(const std::string &text);

void onCancel();

void drawPopup(OLEDDisplay *display);

VirtualKeyboard *keyboard = nullptr;

std::function<void(const std::string &)> callback;

char popupTitle[64] = {0};

char popupMessage[256] = {0};

uint32_t popupUntil = 0;

bool popupVisible = false;