src/win32/base/indicator_visibility_tracker.h

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#ifndef MOZC_WIN32_BASE_INDICATOR_VISIBILITY_TRACKER_H_
#define MOZC_WIN32_BASE_INDICATOR_VISIBILITY_TRACKER_H_

#include <windows.h>

#include <memory>

#include "base/port.h"
#include "win32/base/keyboard.h"

namespace mozc {
namespace win32 {

class IndicatorVisibilityTracker {
 public:
  enum Action {
    kNothing,   // The caller has nothing to do.
    kUpdateUI,  // The caller must update UI for the indicator.
  };
  IndicatorVisibilityTracker();
  ~IndicatorVisibilityTracker();

  // Event call back endpoints.
  Action OnDissociateContext();
  Action OnTestKey(const VirtualKey &key, bool is_down, bool eaten);
  Action OnKey(const VirtualKey &key, bool is_down, bool eaten);
  Action OnMoveFocusedWindow();
  Action OnChangeInputMode();

  // Returns if the indicator should be displayed or not.
  bool IsVisible() const;

 private:
  struct InternalState;
  std::unique_ptr<InternalState> state_;
  DISALLOW_COPY_AND_ASSIGN(IndicatorVisibilityTracker);
};

}  // namespace win32
}  // namespace mozc

#endif  // MOZC_WIN32_BASE_INDICATOR_VISIBILITY_TRACKER_H_