accessibilityrenderobject.cpp

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        return false;
    
    // make a platform-specific decision
    if (isAttachment())
        return accessibilityIgnoreAttachment();
    
    return !m_renderer->isListMarker() && !isWebArea();
}

bool AccessibilityRenderObject::isLoaded() const
{
    return !m_renderer->document()->tokenizer();
}

int AccessibilityRenderObject::layoutCount() const
{
    if (!m_renderer->isRenderView())
        return 0;
    return toRenderView(m_renderer)->frameView()->layoutCount();
}

String AccessibilityRenderObject::text() const
{
    if (!isTextControl() || isPasswordField())
        return String();
    
    if (isNativeTextControl())
        return toRenderTextControl(m_renderer)->text();
    
    Node* node = m_renderer->node();
    if (!node)
        return String();
    if (!node->isElementNode())
        return String();
    
    return static_cast<Element*>(node)->innerText();
}
    
int AccessibilityRenderObject::textLength() const
{
    ASSERT(isTextControl());
    
    if (isPasswordField())
        return -1; // need to return something distinct from 0
    
    return text().length();
}

PassRefPtr<Range> AccessibilityRenderObject::ariaSelectedTextDOMRange() const
{
    Node* node = m_renderer->node();
    if (!node)
        return 0;
    
    RefPtr<Range> currentSelectionRange = selection().toNormalizedRange();
    if (!currentSelectionRange)
        return 0;
    
    ExceptionCode ec = 0;
    if (!currentSelectionRange->intersectsNode(node, ec))
        return Range::create(currentSelectionRange->ownerDocument());
    
    RefPtr<Range> ariaRange = rangeOfContents(node);
    Position startPosition, endPosition;
    
    // Find intersection of currentSelectionRange and ariaRange
    if (ariaRange->startOffset() > currentSelectionRange->startOffset())
        startPosition = ariaRange->startPosition();
    else
        startPosition = currentSelectionRange->startPosition();
    
    if (ariaRange->endOffset() < currentSelectionRange->endOffset())
        endPosition = ariaRange->endPosition();
    else
        endPosition = currentSelectionRange->endPosition();
    
    return Range::create(ariaRange->ownerDocument(), startPosition, endPosition);
}

String AccessibilityRenderObject::selectedText() const
{
    ASSERT(isTextControl());
    
    if (isPasswordField())
        return String(); // need to return something distinct from empty string
    
    if (isNativeTextControl()) {
        RenderTextControl* textControl = toRenderTextControl(m_renderer);
        return textControl->text().substring(textControl->selectionStart(), textControl->selectionEnd() - textControl->selectionStart());
    }
    
    if (ariaRoleAttribute() == UnknownRole)
        return String();
    
    RefPtr<Range> ariaRange = ariaSelectedTextDOMRange();
    if (!ariaRange)
        return String();
    return ariaRange->text();
}

const AtomicString& AccessibilityRenderObject::accessKey() const
{
    Node* node = m_renderer->node();
    if (!node)
        return nullAtom;
    if (!node->isElementNode())
        return nullAtom;
    return static_cast<Element*>(node)->getAttribute(accesskeyAttr);
}

VisibleSelection AccessibilityRenderObject::selection() const
{
    return m_renderer->document()->frame()->selection()->selection();
}

PlainTextRange AccessibilityRenderObject::selectedTextRange() const
{
    ASSERT(isTextControl());
    
    if (isPasswordField())
        return PlainTextRange();
    
    AccessibilityRole ariaRole = ariaRoleAttribute();
    if (isNativeTextControl() && ariaRole == UnknownRole) {
        RenderTextControl* textControl = toRenderTextControl(m_renderer);
        return PlainTextRange(textControl->selectionStart(), textControl->selectionEnd() - textControl->selectionStart());
    }
    
    if (ariaRole == UnknownRole)
        return PlainTextRange();
    
    RefPtr<Range> ariaRange = ariaSelectedTextDOMRange();
    if (!ariaRange)
        return PlainTextRange();
    return PlainTextRange(ariaRange->startOffset(), ariaRange->endOffset());
}

void AccessibilityRenderObject::setSelectedTextRange(const PlainTextRange& range)
{
    if (isNativeTextControl()) {
        RenderTextControl* textControl = toRenderTextControl(m_renderer);
        textControl->setSelectionRange(range.start, range.start + range.length);
        return;
    }
    
    Document* document = m_renderer->document();
    if (!document)
        return;
    Frame* frame = document->frame();
    if (!frame)
        return;
    Node* node = m_renderer->node();
    frame->selection()->setSelection(VisibleSelection(Position(node, range.start),
        Position(node, range.start + range.length), DOWNSTREAM));
}

KURL AccessibilityRenderObject::url() const
{
    if (isAnchor() && m_renderer->node()->hasTagName(aTag)) {
        if (HTMLAnchorElement* anchor = static_cast<HTMLAnchorElement*>(anchorElement()))
            return anchor->href();
    }
    
    if (isWebArea())
        return m_renderer->document()->url();
    
    if (isImage() && m_renderer->node() && m_renderer->node()->hasTagName(imgTag))
        return static_cast<HTMLImageElement*>(m_renderer->node())->src();
    
    if (isInputImage())
        return static_cast<HTMLInputElement*>(m_renderer->node())->src();
    
    return KURL();
}

bool AccessibilityRenderObject::isVisited() const
{
    return m_renderer->style()->pseudoState() == PseudoVisited;
}

bool AccessibilityRenderObject::isSelected() const
{
    if (!m_renderer)
        return false;
    
    Node* node = m_renderer->node();
    if (!node)
        return false;
    
    return false;
}

bool AccessibilityRenderObject::isFocused() const
{
    if (!m_renderer)
        return false;
    
    Document* document = m_renderer->document();
    if (!document)
        return false;
    
    Node* focusedNode = document->focusedNode();
    if (!focusedNode)
        return false;
    
    // A web area is represented by the Document node in the DOM tree, which isn't focusable.
    // Check instead if the frame's selection controller is focused
    if (focusedNode == m_renderer->node() || 
        (roleValue() == WebAreaRole && document->frame()->selection()->isFocusedAndActive()))
        return true;
    
    return false;
}

void AccessibilityRenderObject::setFocused(bool on)
{
    if (!canSetFocusAttribute())
        return;
    
    if (!on)
        m_renderer->document()->setFocusedNode(0);
    else {
        if (m_renderer->node()->isElementNode())
            static_cast<Element*>(m_renderer->node())->focus();
        else
            m_renderer->document()->setFocusedNode(m_renderer->node());
    }
}

void AccessibilityRenderObject::setValue(const String& string)
{
    // FIXME: Do we want to do anything here for ARIA textboxes?
    if (m_renderer->isTextField()) {
        HTMLInputElement* input = static_cast<HTMLInputElement*>(m_renderer->node());
        input->setValue(string);
    } else if (m_renderer->isTextArea()) {
        HTMLTextAreaElement* textArea = static_cast<HTMLTextAreaElement*>(m_renderer->node());
        textArea->setValue(string);
    }
}

bool AccessibilityRenderObject::isEnabled() const
{
    ASSERT(m_renderer);
    if (!m_renderer->node() || !m_renderer->node()->isElementNode())
        return true;

    FormControlElement* formControlElement = toFormControlElement(static_cast<Element*>(m_renderer->node()));
    if (!formControlElement)
        return true;

    return formControlElement->isEnabled();    
}

RenderView* AccessibilityRenderObject::topRenderer() const
{
    return m_renderer->document()->topDocument()->renderView();
}

Document* AccessibilityRenderObject::document() const
{
    return m_renderer->document();
}

FrameView* AccessibilityRenderObject::topDocumentFrameView() const
{
    return topRenderer()->view()->frameView();
}

Widget* AccessibilityRenderObject::widget() const
{
    if (!m_renderer->isWidget())
        return 0;
    
    return static_cast<RenderWidget*>(m_renderer)->widget();
}

AXObjectCache* AccessibilityRenderObject::axObjectCache() const
{
    return m_renderer->document()->axObjectCache();
}

AccessibilityObject* AccessibilityRenderObject::accessibilityParentForImageMap(HTMLMapElement* map) const
{
    // find an image that is using this map
    if (!m_renderer || !map)
        return 0;

    RefPtr<HTMLCollection> coll = m_renderer->document()->images();
    for (Node* curr = coll->firstItem(); curr; curr = coll->nextItem()) {
        RenderObject* obj = curr->renderer();
        if (!obj || !curr->hasTagName(imgTag))
            continue;
        
        // The HTMLImageElement's useMap() value includes the '#' symbol at the beginning,
        // which has to be stripped off
        if (static_cast<HTMLImageElement*>(curr)->useMap().substring(1) == map->getName())
            return axObjectCache()->getOrCreate(obj);
    }
    
    return 0;
}
    
void AccessibilityRenderObject::getDocumentLinks(AccessibilityChildrenVector& result)
{
    Document* document = m_renderer->document();
    RefPtr<HTMLCollection> coll = document->links();
    Node* curr = coll->firstItem();
    while (curr) {
        RenderObject* obj = curr->renderer();
        if (obj) {
            RefPtr<AccessibilityObject> axobj = document->axObjectCache()->getOrCreate(obj);
            ASSERT(axobj);
            ASSERT(axobj->roleValue() == WebCoreLinkRole);
            if (!axobj->accessibilityIsIgnored())
                result.append(axobj);
        } else {
            Node* parent = curr->parent();
            if (parent && curr->hasTagName(areaTag) && parent->hasTagName(mapTag)) {
                AccessibilityImageMapLink* areaObject = static_cast<AccessibilityImageMapLink*>(axObjectCache()->getOrCreate(ImageMapLinkRole));
                areaObject->setHTMLAreaElement(static_cast<HTMLAreaElement*>(curr));
                areaObject->setHTMLMapElement(static_cast<HTMLMapElement*>(parent));
                areaObject->setParent(accessibilityParentForImageMap(static_cast<HTMLMapElement*>(parent)));

                result.append(areaObject);
            }
        }
        curr = coll->nextItem();
    }
}

FrameView* AccessibilityRenderObject::documentFrameView() const 
{ 
    if (!m_renderer || !m_renderer->document()) 
        return 0; 

    // this is the RenderObject's Document's Frame's FrameView 
    return m_renderer->document()->view();
}

Widget* AccessibilityRenderObject::widgetForAttachmentView() const
{
    if (!isAttachment())
        return 0;
    return static_cast<RenderWidget*>(m_renderer)->widget();
}

FrameView* AccessibilityRenderObject::frameViewIfRenderView() const
{
    if (!m_renderer->isRenderView())
        return 0;
    // this is the RenderObject's Document's renderer's FrameView
    return m_renderer->view()->frameView();
}

// This function is like a cross-platform version of - (WebCoreTextMarkerRange*)textMarkerRange. It returns
// a Range that we can convert to a WebCoreTextMarkerRange in the Obj-C file
VisiblePositionRange AccessibilityRenderObject::visiblePositionRange() const
{
    if (!m_renderer)
        return VisiblePositionRange();
    
    // construct VisiblePositions for start and end
    Node* node = m_renderer->node();
    if (!node)
        return VisiblePositionRange();
    
    VisiblePosition startPos = VisiblePosition(node, 0, VP_DEFAULT_AFFINITY);
    VisiblePosition endPos = VisiblePosition(node, maxDeepOffset(node), VP_DEFAULT_AFFINITY);
    
    // the VisiblePositions are equal for nodes like buttons, so adjust for that
    if (startPos == endPos) {
        endPos = endPos.next();
        if (endPos.isNull())
            endPos = startPos;
    }
    
    return VisiblePositionRange(startPos, endPos);
}

VisiblePositionRange AccessibilityRenderObject::visiblePositionRangeForLine(unsigned lineCount) const
{
    if (lineCount == 0 || !m_renderer)
        return VisiblePositionRange();
    
    // iterate over the lines
    // FIXME: this is wrong when lineNumber is lineCount+1,  because nextLinePosition takes you to the
    // last offset of the last line
    VisiblePosition visiblePos = m_renderer->document()->renderer()->positionForCoordinates(0, 0);
    VisiblePosition savedVisiblePos;
    while (--lineCount != 0) {
        savedVisiblePos = visiblePos;
        visiblePos = nextLinePosition(visiblePos, 0);
        if (visiblePos.isNull() || visiblePos == savedVisiblePos)
            return VisiblePositionRange();
    }
    
    // make a caret selection for the marker position, then extend it to the line
    // NOTE: ignores results of sel.modify because it returns false when
    // starting at an empty line.  The resulting selection in that case
    // will be a caret at visiblePos.
    SelectionController selection;
    selection.setSelection(VisibleSelection(visiblePos));
    selection.modify(SelectionController::EXTEND, SelectionController::RIGHT, LineBoundary);
    
    return VisiblePositionRange(selection.selection().visibleStart(), selection.selection().visibleEnd());
}
    
VisiblePosition AccessibilityRenderObject::visiblePositionForIndex(int index) const
{
    if (!m_renderer)
        return VisiblePosition();