text: // Copyright 2014 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #ifndef UI_BASE_IME_CHROMEOS_IME_KEYBOARD_H_
  #define UI_BASE_IME_CHROMEOS_IME_KEYBOARD_H_
  
  #include <string>
  #include <vector>
  
  #include "base/component_export.h"
  #include "base/observer_list.h"
  
  namespace chromeos {
  namespace input_method {
  
  struct AutoRepeatRate {
    AutoRepeatRate() : initial_delay_in_ms(0), repeat_interval_in_ms(0) {}
    unsigned int initial_delay_in_ms;
    unsigned int repeat_interval_in_ms;
  };
  
  class COMPONENT_EXPORT(UI_BASE_IME_CHROMEOS) ImeKeyboard {
   public:
    class Observer {
     public:
      // Called when the caps lock state has changed.
      virtual void OnCapsLockChanged(bool enabled) = 0;
  
      // Called when the layout state is changing.
      virtual void OnLayoutChanging(const std::string& layout_name) = 0;
    };
  
    ImeKeyboard();
    virtual ~ImeKeyboard();
    // Adds/removes observer.
    virtual void AddObserver(Observer* observer);
    virtual void RemoveObserver(Observer* observer);
  
    // Sets the current keyboard layout to |layout_name|. This function does not
    // change the current mapping of the modifier keys. Returns true on success.
    virtual bool SetCurrentKeyboardLayoutByName(const std::string& layout_name);
  
    // Gets the current keyboard layout name.
    const std::string& GetCurrentKeyboardLayoutName() const {
      return last_layout_;
    }
  
    // Sets the current keyboard layout again. We have to call the function every
    // time when "x11::Input::HierarchyEvent::opcode" XInput2 event is sent to
    // Chrome. See xinput_hierarchy_changed_event_listener.h for details.
    virtual bool ReapplyCurrentKeyboardLayout() = 0;
  
    // Updates keyboard LEDs on all keyboards.
    // XKB asymmetrically propagates keyboard modifier indicator state changes to
    // slave keyboards. If the state change is initiated from a client to the
    // "core/master keyboard", XKB changes global state and pushes an indication
    // change down to all keyboards. If the state change is initiated by one slave
    // (physical) keyboard, it changes global state but only pushes an indicator
    // state change down to that one keyboard.
    // This function changes LEDs on all keyboards by explicitly updating the
    // core/master keyboard.
    virtual void ReapplyCurrentModifierLockStatus() = 0;
  
    // Disables the num lock.
    virtual void DisableNumLock() = 0;
  
    // Sets the caps lock status to |enable_caps_lock|. Do not call the function
    // from non-UI threads.
    virtual void SetCapsLockEnabled(bool enable_caps_lock);
  
    // Returns true if caps lock is enabled. Do not call the function from non-UI
    // threads.
    virtual bool CapsLockIsEnabled();
  
    // Returns true if the current layout supports ISO Level 5 shift.
    virtual bool IsISOLevel5ShiftAvailable() const;
  
    // Returns true if the current layout supports alt gr.
    virtual bool IsAltGrAvailable() const;
  
    // Turns on and off the auto-repeat of the keyboard. Returns true on success.
    // Do not call the function from non-UI threads.
    virtual bool SetAutoRepeatEnabled(bool enabled) = 0;
  
    // Returns true if auto-repeat is enabled.
    virtual bool GetAutoRepeatEnabled() = 0;
  
    // Sets the auto-repeat rate of the keyboard, initial delay in ms, and repeat
    // interval in ms.  Returns true on success. Do not call the function from
    // non-UI threads.
    virtual bool SetAutoRepeatRate(const AutoRepeatRate& rate) = 0;
  
    bool caps_lock_is_enabled_;
    std::string last_layout_;
  
   private:
    base::ObserverList<Observer>::Unchecked observers_;
  };
  
  }  // namespace input_method
  }  // namespace chromeos
  
  #endif  // UI_BASE_IME_CHROMEOS_IME_KEYBOARD_H_
  