Source/WebCore/accessibility/AccessibilitySlider.cpp

/*
 * Copyright (C) 2009 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.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "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 OR ITS 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 "AccessibilitySlider.h"

#include "AXObjectCache.h"
#include "HTMLInputElement.h"
#include "HTMLNames.h"
#include "RenderObject.h"
#include "RenderSlider.h"

namespace WebCore {
    
using namespace HTMLNames;

AccessibilitySlider::AccessibilitySlider(RenderObject* renderer)
    : AccessibilityRenderObject(renderer)
{
}

PassRefPtr<AccessibilitySlider> AccessibilitySlider::create(RenderObject* renderer)
{
    return adoptRef(new AccessibilitySlider(renderer));
}

const AccessibilityObject::AccessibilityChildrenVector& AccessibilitySlider::children()
{
    if (!m_haveChildren)
        addChildren();
    return m_children;
}

AccessibilityOrientation AccessibilitySlider::orientation() const
{
    // Default to horizontal in the unknown case.
    if (!m_renderer)
        return AccessibilityOrientationHorizontal;
    
    RenderStyle* style = m_renderer->style();
    if (!style)
        return AccessibilityOrientationHorizontal;
    
    ControlPart styleAppearance = style->appearance();
    switch (styleAppearance) {
    case SliderThumbHorizontalPart:
    case SliderHorizontalPart:
    case MediaSliderPart:
        return AccessibilityOrientationHorizontal;
    
    case SliderThumbVerticalPart: 
    case SliderVerticalPart:
    case MediaVolumeSliderPart:
        return AccessibilityOrientationVertical;
        
    default:
        return AccessibilityOrientationHorizontal;
    }
}
    
void AccessibilitySlider::addChildren()
{
    ASSERT(!m_haveChildren); 
    
    m_haveChildren = true;

    AXObjectCache* cache = m_renderer->document()->axObjectCache();

    AccessibilitySliderThumb* thumb = static_cast<AccessibilitySliderThumb*>(cache->getOrCreate(SliderThumbRole));
    thumb->setParentObject(this);

    // Before actually adding the value indicator to the hierarchy,
    // allow the platform to make a final decision about it.
    if (thumb->accessibilityIsIgnored())
        cache->remove(thumb->axObjectID());
    else
        m_children.append(thumb);
}

const AtomicString& AccessibilitySlider::getAttribute(const QualifiedName& attribute) const
{
    return element()->getAttribute(attribute);
}
    
AccessibilityObject* AccessibilitySlider::elementAccessibilityHitTest(const IntPoint& point) const
{
    if (m_children.size()) {
        ASSERT(m_children.size() == 1);
        if (m_children[0]->elementRect().contains(point))
            return m_children[0].get();
    }
    
    return axObjectCache()->getOrCreate(m_renderer);
}

bool AccessibilitySlider::accessibilityIsIgnored() const
{
    AccessibilityObjectInclusion decision = accessibilityIsIgnoredBase();
    if (decision == IncludeObject)
        return false;
    if (decision == IgnoreObject)
        return true;
    
    return false;
}
    
float AccessibilitySlider::valueForRange() const
{
    return element()->value().toFloat();
}

float AccessibilitySlider::maxValueForRange() const
{
    return static_cast<float>(element()->maximum());
}

float AccessibilitySlider::minValueForRange() const
{
    return static_cast<float>(element()->minimum());
}

void AccessibilitySlider::setValue(const String& value)
{
    HTMLInputElement* input = element();
    
    if (input->value() == value)
        return;

    input->setValue(value);

    // Fire change event manually, as RenderSlider::setValueForPosition does.
    input->dispatchFormControlChangeEvent();
}

HTMLInputElement* AccessibilitySlider::element() const
{
    return static_cast<HTMLInputElement*>(m_renderer->node());
}


AccessibilitySliderThumb::AccessibilitySliderThumb()
    : m_parentSlider(0)
{
}

PassRefPtr<AccessibilitySliderThumb> AccessibilitySliderThumb::create()
{
    return adoptRef(new AccessibilitySliderThumb());
}
    
IntRect AccessibilitySliderThumb::elementRect() const
{
    if (!m_parentSlider->renderer())
        return IntRect();

    IntRect intRect = toRenderSlider(m_parentSlider->renderer())->thumbRect();
    FloatQuad floatQuad = m_parentSlider->renderer()->localToAbsoluteQuad(FloatRect(intRect));

    return floatQuad.enclosingBoundingBox();
}

IntSize AccessibilitySliderThumb::size() const
{
    return elementRect().size();
}

bool AccessibilitySliderThumb::accessibilityIsIgnored() const
{
    AccessibilityObjectInclusion decision = accessibilityPlatformIncludesObject();
    if (decision == IncludeObject)
        return false;
    if (decision == IgnoreObject)
        return true;

    return false;
}

} // namespace WebCore