/*

 * Copyright (C) 2008 Apple Inc. All Rights Reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 

 */

#ifndef ScrollbarTheme_h

#define ScrollbarTheme_h

#include "GraphicsContext.h"

#include "IntRect.h"

#include "ScrollTypes.h"

namespace WebCore {

class PlatformMouseEvent;

class Scrollbar;

class ScrollView;

class ScrollbarTheme : public Noncopyable {

public:

    virtual ~ScrollbarTheme() {};

    virtual bool paint(Scrollbar*, GraphicsContext*, const IntRect& /*damageRect*/) { return false; }

    virtual ScrollbarPart hitTest(Scrollbar*, const PlatformMouseEvent&) { return NoPart; }

    virtual int scrollbarThickness(ScrollbarControlSize = RegularScrollbar) { return 0; }

    virtual ScrollbarButtonsPlacement buttonsPlacement() const { return ScrollbarButtonsSingle; }

    virtual bool supportsControlTints() const { return false; }

    virtual void themeChanged() {}

    virtual bool invalidateOnMouseEnterExit() { return false; }

    void invalidateParts(Scrollbar* scrollbar, ScrollbarControlPartMask mask)

    {

        if (mask & BackButtonStartPart)

            invalidatePart(scrollbar, BackButtonStartPart);

        if (mask & ForwardButtonStartPart)

            invalidatePart(scrollbar, ForwardButtonStartPart);

        if (mask & BackTrackPart)

            invalidatePart(scrollbar, BackTrackPart);

        if (mask & ThumbPart)

            invalidatePart(scrollbar, ThumbPart);

        if (mask & ForwardTrackPart)

            invalidatePart(scrollbar, ForwardTrackPart);

        if (mask & BackButtonEndPart)

            invalidatePart(scrollbar, BackButtonEndPart);

        if (mask & ForwardButtonEndPart)

            invalidatePart(scrollbar, ForwardButtonEndPart);

    }

    virtual void invalidatePart(Scrollbar*, ScrollbarPart) {}

    virtual void paintScrollCorner(ScrollView*, GraphicsContext* context, const IntRect& cornerRect) { context->fillRect(cornerRect, Color::white, DeviceColorSpace); }

    virtual bool shouldCenterOnThumb(Scrollbar*, const PlatformMouseEvent&) { return false; }

    virtual bool shouldSnapBackToDragOrigin(Scrollbar*, const PlatformMouseEvent&) { return false; }

    virtual int thumbPosition(Scrollbar*) { return 0; } // The position of the thumb relative to the track.

    virtual int thumbLength(Scrollbar*) { return 0; } // The length of the thumb along the axis of the scrollbar.

    virtual int trackPosition(Scrollbar*) { return 0; } // The position of the track relative to the scrollbar.

    virtual int trackLength(Scrollbar*) { return 0; } // The length of the track along the axis of the scrollbar.

    virtual int maxOverlapBetweenPages() { return std::numeric_limits<int>::max(); }

    virtual double initialAutoscrollTimerDelay() { return 0.25; }

    virtual double autoscrollTimerDelay() { return 0.05; }

    virtual void registerScrollbar(Scrollbar*) {}

    virtual void unregisterScrollbar(Scrollbar*) {}

    static ScrollbarTheme* nativeTheme(); // Must be implemented to return the correct theme subclass.

};

}

#endif