// Copyright 2010-2012, Google Inc.
// Copyright 2012-2017, Weng Xuetian <wengxt@gmail.com>
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#ifndef UNIX_FCITX5_FCITX_KEY_EVENT_HANDLER_H_
#define UNIX_FCITX5_FCITX_KEY_EVENT_HANDLER_H_

#include <fcitx-utils/key.h>

#include <memory>
#include <set>

#include "base/port.h"
#include "protocol/commands.pb.h"
#include "protocol/config.pb.h"
#include "unix/fcitx5/fcitx_key_translator.h"

namespace fcitx {

class KeyEventHandler {
 public:
  KeyEventHandler();

  // Converts a key event came from fcitx to commands::KeyEvent. This is a
  // stateful method. It stores modifier keys states since ibus doesn't send
  // an enough information about the modifier keys.
  bool GetKeyEvent(KeySym keyval, uint32 keycode, KeyStates modifiers,
                   mozc::config::Config::PreeditMethod preedit_method,
                   bool layout_is_jp, bool is_key_up,
                   mozc::commands::KeyEvent *key);

  // Clears states.
  void Clear();

 private:
  // Manages modifier keys. Returns false if it should not be sent to server.
  bool ProcessModifiers(bool is_key_up, uint32 keyval,
                        mozc::commands::KeyEvent *key_event);

  std::unique_ptr<KeyTranslator> key_translator_;
  // Non modifier key is pressed or not after all keys are released.
  bool is_non_modifier_key_pressed_;
  // Currently pressed modifier keys.  It is set of keyval.
  std::set<uint32> currently_pressed_modifiers_;
  // Pending modifier keys.
  std::set<mozc::commands::KeyEvent::ModifierKey> modifiers_to_be_sent_;

  DISALLOW_COPY_AND_ASSIGN(KeyEventHandler);
};

}  // namespace fcitx

#endif  // UNIX_FCITX5_FCITX_KEY_EVENT_HANDLER_H_
