1/*
2 * Copyright (C) 2006, 2007, 2009, 2010, 2011 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef AutoscrollController_h
27#define AutoscrollController_h
28
29#include "IntPoint.h"
30#include "Timer.h"
31
32namespace WebCore {
33
34class EventHandler;
35class Frame;
36class FrameView;
37class Node;
38class PlatformMouseEvent;
39class RenderBox;
40class RenderObject;
41
42enum AutoscrollType {
43    NoAutoscroll,
44    AutoscrollForDragAndDrop,
45    AutoscrollForSelection,
46#if ENABLE(PAN_SCROLLING)
47    AutoscrollForPanCanStop,
48    AutoscrollForPan,
49#endif
50};
51
52// AutscrollController handels autoscroll and pan scroll for EventHandler.
53class AutoscrollController {
54public:
55    AutoscrollController();
56    RenderBox* autoscrollRenderer() const;
57    bool autoscrollInProgress() const;
58    bool panScrollInProgress() const;
59    void startAutoscrollForSelection(RenderObject*);
60    void stopAutoscrollTimer(bool rendererIsBeingDestroyed = false);
61    void updateAutoscrollRenderer();
62    void updateDragAndDrop(Node* targetNode, const IntPoint& eventPosition, double eventTime);
63#if ENABLE(PAN_SCROLLING)
64    void didPanScrollStart();
65    void didPanScrollStop();
66    void handleMouseReleaseEvent(const PlatformMouseEvent&);
67    void setPanScrollInProgress(bool);
68    void startPanScrolling(RenderBox*, const IntPoint&);
69#endif
70
71private:
72    void autoscrollTimerFired(Timer<AutoscrollController>&);
73    void startAutoscrollTimer();
74#if ENABLE(PAN_SCROLLING)
75    void updatePanScrollState(FrameView*, const IntPoint&);
76#endif
77
78    Timer<AutoscrollController> m_autoscrollTimer;
79    RenderBox* m_autoscrollRenderer;
80    AutoscrollType m_autoscrollType;
81    IntPoint m_dragAndDropAutoscrollReferencePosition;
82    double m_dragAndDropAutoscrollStartTime;
83#if ENABLE(PAN_SCROLLING)
84    IntPoint m_panScrollStartPos;
85#endif
86};
87
88} // namespace WebCore
89
90#endif // AutoscrollController_h
91