text: // Copyright (c) 2012 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 ASH_WM_SYSTEM_GESTURE_EVENT_FILTER_H_
  #define ASH_WM_SYSTEM_GESTURE_EVENT_FILTER_H_
  
  #include "ash/shell.h"
  #include "ash/touch/touch_uma.h"
  #include "base/timer/timer.h"
  #include "ui/aura/window_observer.h"
  #include "ui/events/event_handler.h"
  #include "ui/gfx/point.h"
  
  #include <map>
  
  namespace aura {
  class Window;
  }
  
  namespace ui {
  class LocatedEvent;
  }
  
  namespace ash {
  
  namespace test {
  class SystemGestureEventFilterTest;
  }
  
  namespace internal {
  class LongPressAffordanceHandler;
  class OverviewGestureHandler;
  class SystemPinchHandler;
  class TouchUMA;
  class TwoFingerDragHandler;
  
  // An event filter which handles system level gesture events.
  class SystemGestureEventFilter : public ui::EventHandler,
                                   public aura::WindowObserver {
   public:
    SystemGestureEventFilter();
    virtual ~SystemGestureEventFilter();
  
    // Overridden from ui::EventHandler:
    virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
    virtual void OnScrollEvent(ui::ScrollEvent* event) OVERRIDE;
    virtual void OnTouchEvent(ui::TouchEvent* event) OVERRIDE;
    virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
  
    // Overridden from aura::WindowObserver.
    virtual void OnWindowVisibilityChanged(aura::Window* window,
                                           bool visible) OVERRIDE;
    virtual void OnWindowDestroying(aura::Window* window) OVERRIDE;
  
   private:
    friend class ash::test::SystemGestureEventFilterTest;
  
    // Removes system-gesture handlers for a window.
    void ClearGestureHandlerForWindow(aura::Window* window);
  
    typedef std::map<aura::Window*, SystemPinchHandler*> WindowPinchHandlerMap;
    // Created on demand when a system-level pinch gesture is initiated. Destroyed
    // when the system-level pinch gesture ends for the window.
    WindowPinchHandlerMap pinch_handlers_;
  
    bool system_gestures_enabled_;
  
    scoped_ptr<LongPressAffordanceHandler> long_press_affordance_;
    scoped_ptr<OverviewGestureHandler> overview_gesture_handler_;
    scoped_ptr<TwoFingerDragHandler> two_finger_drag_;
  
    DISALLOW_COPY_AND_ASSIGN(SystemGestureEventFilter);
  };
  
  }  // namespace internal
  }  // namespace ash
  
  #endif  // ASH_WM_SYSTEM_GESTURE_EVENT_FILTER_H_
  