/*

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

 * Copyright (C) 2008, 2009 Google Inc.

 *

 * 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.

 */

#include "config.h"

#include "ScrollbarThemeChromium.h"

#include "ChromiumBridge.h"

#include "PlatformMouseEvent.h"

#include "Scrollbar.h"

#include "ScrollbarClient.h"

#include "ScrollbarThemeComposite.h"

// -----------------------------------------------------------------------------

// This file contains scrollbar theme code that is cross platform. Additional

// members of ScrollbarThemeChromium can be found in the platform specific files

// -----------------------------------------------------------------------------

namespace WebCore {

bool ScrollbarThemeChromium::hasThumb(Scrollbar* scrollbar)

{

    // This method is just called as a paint-time optimization to see if

    // painting the thumb can be skipped.  We don't have to be exact here.

    return thumbLength(scrollbar) > 0;

}

IntRect ScrollbarThemeChromium::backButtonRect(Scrollbar* scrollbar, ScrollbarPart part, bool)

{

    // Windows and Linux just have single arrows.

    if (part == BackButtonEndPart)

        return IntRect();

    IntSize size = buttonSize(scrollbar);

    return IntRect(scrollbar->x(), scrollbar->y(), size.width(), size.height());

}

IntRect ScrollbarThemeChromium::forwardButtonRect(Scrollbar* scrollbar, ScrollbarPart part, bool)

{

    // Windows and Linux just have single arrows.

    if (part == ForwardButtonStartPart)

        return IntRect();

    IntSize size = buttonSize(scrollbar);

    int x, y;

    if (scrollbar->orientation() == HorizontalScrollbar) {

        x = scrollbar->x() + scrollbar->width() - size.width();

        y = scrollbar->y();

    } else {

        x = scrollbar->x();

        y = scrollbar->y() + scrollbar->height() - size.height();

    }

    return IntRect(x, y, size.width(), size.height());

}

IntRect ScrollbarThemeChromium::trackRect(Scrollbar* scrollbar, bool)

{

    IntSize bs = buttonSize(scrollbar);

    // The buttons at the top and bottom of the scrollbar are square, so the

    // thickness of the scrollbar is also their height.

    int thickness = scrollbarThickness(scrollbar->controlSize());

    if (scrollbar->orientation() == HorizontalScrollbar) {

        // Once the scrollbar becomes smaller than the natural size of the

        // two buttons, the track disappears.

        if (scrollbar->width() < 2 * thickness)

            return IntRect();

        return IntRect(scrollbar->x() + bs.width(), scrollbar->y(), scrollbar->width() - 2 * bs.width(), thickness);

    }

    if (scrollbar->height() < 2 * thickness)

        return IntRect();

    return IntRect(scrollbar->x(), scrollbar->y() + bs.height(), thickness, scrollbar->height() - 2 * bs.height());

}

void ScrollbarThemeChromium::paintTrackBackground(GraphicsContext* context, Scrollbar* scrollbar, const IntRect& rect)

{

    // Just assume a forward track part.  We only paint the track as a single piece when there is no thumb.

    if (!hasThumb(scrollbar))

        paintTrackPiece(context, scrollbar, rect, ForwardTrackPart);

}

void ScrollbarThemeChromium::paintTickmarks(GraphicsContext* context, Scrollbar* scrollbar, const IntRect& rect)

{

    if (scrollbar->orientation() != VerticalScrollbar)

        return;

    if (rect.height() <= 0 || rect.width() <= 0)

        return;  // nothing to draw on.

    // Get the tickmarks for the frameview.

    Vector<IntRect> tickmarks;

    scrollbar->client()->getTickmarks(tickmarks);

    if (!tickmarks.size())

        return;

    // Get the image for the tickmarks.

    static RefPtr<Image> dash = Image::loadPlatformResource("tickmarkDash");

    if (dash->isNull()) {

        ASSERT_NOT_REACHED();

        return;

    }

    context->save();

    for (Vector<IntRect>::const_iterator i = tickmarks.begin(); i != tickmarks.end(); ++i) {

        // Calculate how far down (in %) the tick-mark should appear.

        const float percent = static_cast<float>(i->y()) / scrollbar->totalSize();

        // Calculate how far down (in pixels) the tick-mark should appear.

        const int yPos = rect.topLeft().y() + (rect.height() * percent);

        IntPoint tick(scrollbar->x(), yPos);

        context->drawImage(dash.get(), DeviceColorSpace, tick);

    }

    context->restore();

}

void ScrollbarThemeChromium::paintScrollCorner(ScrollView* view, GraphicsContext* context, const IntRect& cornerRect)

{

    // ScrollbarThemeComposite::paintScrollCorner incorrectly assumes that the

    // ScrollView is a FrameView (see FramelessScrollView), so we cannot let

    // that code run.  For FrameView's this is correct since we don't do custom

    // scrollbar corner rendering, which ScrollbarThemeComposite supports.

    ScrollbarTheme::paintScrollCorner(view, context, cornerRect);

}

} // namespace WebCore