element.cpp

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            lastElementBeforeInsertion->renderStyle() && lastElementBeforeInsertion->renderStyle()->lastChildState())
            lastElementBeforeInsertion->setChanged();
            
        // We also have to handle node removal.  The parser callback case is similar to node removal as well in that we need to change the last child
        // to match now.
        if ((childCountDelta < 0 || finishedParsingCallback) && newLastChild == lastElementBeforeInsertion && newLastChild && newLastChild->renderStyle() && !newLastChild->renderStyle()->lastChildState())
            newLastChild->setChanged();
    }

    // The + selector.  We need to invalidate the first element following the insertion point.  It is the only possible element
    // that could be affected by this DOM change.
    if (style->childrenAffectedByDirectAdjacentRules() && afterChange) {
        Node* firstElementAfterInsertion = 0;
        for (firstElementAfterInsertion = afterChange;
             firstElementAfterInsertion && !firstElementAfterInsertion->isElementNode();
             firstElementAfterInsertion = firstElementAfterInsertion->nextSibling()) {};
        if (firstElementAfterInsertion && firstElementAfterInsertion->attached())
            firstElementAfterInsertion->setChanged();
    }

    // Forward positional selectors include the ~ selector, nth-child, nth-of-type, first-of-type and only-of-type.
    // Backward positional selectors include nth-last-child, nth-last-of-type, last-of-type and only-of-type.
    // We have to invalidate everything following the insertion point in the forward case, and everything before the insertion point in the
    // backward case.
    // |afterChange| is 0 in the parser callback case, so we won't do any work for the forward case if we don't have to.
    // For performance reasons we just mark the parent node as changed, since we don't want to make childrenChanged O(n^2) by crawling all our kids
    // here.  recalcStyle will then force a walk of the children when it sees that this has happened.
    if ((style->childrenAffectedByForwardPositionalRules() && afterChange) ||
        (style->childrenAffectedByBackwardPositionalRules() && beforeChange))
        e->setChanged();
    
    // :empty selector.
    if (style->affectedByEmpty() && (!style->emptyState() || e->hasChildNodes()))
        e->setChanged();
}

void Element::childrenChanged(bool changedByParser, Node* beforeChange, Node* afterChange, int childCountDelta)
{
    ContainerNode::childrenChanged(changedByParser, beforeChange, afterChange, childCountDelta);
    if (!changedByParser)
        checkForSiblingStyleChanges(this, renderStyle(), false, beforeChange, afterChange, childCountDelta);
}

void Element::finishParsingChildren()
{
    ContainerNode::finishParsingChildren();
    m_parsingChildrenFinished = true;
    checkForSiblingStyleChanges(this, renderStyle(), true, lastChild(), 0, 0);
}

void Element::dispatchAttrRemovalEvent(Attribute*)
{
    ASSERT(!eventDispatchForbidden());
#if 0
    if (!document()->hasListenerType(Document::DOMATTRMODIFIED_LISTENER))
        return;
    ExceptionCode ec = 0;
    dispatchEvent(new MutationEvent(DOMAttrModifiedEvent, true, false, attr, attr->value(),
        attr->value(), document()->attrName(attr->id()), MutationEvent::REMOVAL), ec);
#endif
}

void Element::dispatchAttrAdditionEvent(Attribute*)
{
    ASSERT(!eventDispatchForbidden());
#if 0
    if (!document()->hasListenerType(Document::DOMATTRMODIFIED_LISTENER))
        return;
    ExceptionCode ec = 0;
    dispatchEvent(new MutationEvent(DOMAttrModifiedEvent, true, false, attr, attr->value(),
        attr->value(),document()->attrName(attr->id()), MutationEvent::ADDITION), ec);
#endif
}

String Element::openTagStartToString() const
{
    String result = "<" + nodeName();

    NamedAttrMap *attrMap = attributes(true);

    if (attrMap) {
        unsigned numAttrs = attrMap->length();
        for (unsigned i = 0; i < numAttrs; i++) {
            result += " ";

            Attribute *attribute = attrMap->attributeItem(i);
            result += attribute->name().toString();
            if (!attribute->value().isNull()) {
                result += "=\"";
                // FIXME: substitute entities for any instances of " or '
                result += attribute->value();
                result += "\"";
            }
        }
    }

    return result;
}

void Element::updateId(const AtomicString& oldId, const AtomicString& newId)
{
    if (!inDocument())
        return;

    if (oldId == newId)
        return;

    Document* doc = document();
    if (!oldId.isEmpty())
        doc->removeElementById(oldId, this);
    if (!newId.isEmpty())
        doc->addElementById(newId, this);
}

#ifndef NDEBUG
void Element::formatForDebugger(char* buffer, unsigned length) const
{
    String result;
    String s;
    
    s = nodeName();
    if (s.length() > 0) {
        result += s;
    }
          
    s = getAttribute(idAttr);
    if (s.length() > 0) {
        if (result.length() > 0)
            result += "; ";
        result += "id=";
        result += s;
    }
          
    s = getAttribute(classAttr);
    if (s.length() > 0) {
        if (result.length() > 0)
            result += "; ";
        result += "class=";
        result += s;
    }
          
    strncpy(buffer, result.utf8().data(), length - 1);
}
#endif

PassRefPtr<Attr> Element::setAttributeNode(Attr* attr, ExceptionCode& ec)
{
    if (!attr) {
        ec = TYPE_MISMATCH_ERR;
        return 0;
    }
    return static_pointer_cast<Attr>(attributes(false)->setNamedItem(attr, ec));
}

PassRefPtr<Attr> Element::setAttributeNodeNS(Attr* attr, ExceptionCode& ec)
{
    if (!attr) {
        ec = TYPE_MISMATCH_ERR;
        return 0;
    }
    return static_pointer_cast<Attr>(attributes(false)->setNamedItem(attr, ec));
}

PassRefPtr<Attr> Element::removeAttributeNode(Attr* attr, ExceptionCode& ec)
{
    if (!attr) {
        ec = TYPE_MISMATCH_ERR;
        return 0;
    }
    if (attr->ownerElement() != this) {
        ec = NOT_FOUND_ERR;
        return 0;
    }
    if (document() != attr->document()) {
        ec = WRONG_DOCUMENT_ERR;
        return 0;
    }

    NamedAttrMap *attrs = attributes(true);
    if (!attrs)
        return 0;

    return static_pointer_cast<Attr>(attrs->removeNamedItem(attr->qualifiedName(), ec));
}

void Element::setAttributeNS(const AtomicString& namespaceURI, const AtomicString& qualifiedName, const AtomicString& value, ExceptionCode& ec)
{
    String prefix, localName;
    if (!Document::parseQualifiedName(qualifiedName, prefix, localName, ec))
        return;

    QualifiedName qName(prefix, localName, namespaceURI);
    setAttribute(qName, value, ec);
}

void Element::removeAttribute(const String& name, ExceptionCode& ec)
{
    String localName = shouldIgnoreAttributeCase(this) ? name.lower() : name;

    if (namedAttrMap) {
        namedAttrMap->removeNamedItem(localName, ec);
        if (ec == NOT_FOUND_ERR)
            ec = 0;
    }
}

void Element::removeAttributeNS(const String& namespaceURI, const String& localName, ExceptionCode& ec)
{
    removeAttribute(QualifiedName(nullAtom, localName, namespaceURI), ec);
}

PassRefPtr<Attr> Element::getAttributeNode(const String& name)
{
    NamedAttrMap* attrs = attributes(true);
    if (!attrs)
        return 0;
    String localName = shouldIgnoreAttributeCase(this) ? name.lower() : name;
    return static_pointer_cast<Attr>(attrs->getNamedItem(localName));
}

PassRefPtr<Attr> Element::getAttributeNodeNS(const String& namespaceURI, const String& localName)
{
    NamedAttrMap* attrs = attributes(true);
    if (!attrs)
        return 0;
    return static_pointer_cast<Attr>(attrs->getNamedItem(QualifiedName(nullAtom, localName, namespaceURI)));
}

bool Element::hasAttribute(const String& name) const
{
    NamedAttrMap* attrs = attributes(true);
    if (!attrs)
        return false;

    // This call to String::lower() seems to be required but
    // there may be a way to remove it.
    String localName = shouldIgnoreAttributeCase(this) ? name.lower() : name;
    return attrs->getAttributeItem(localName, false);
}

bool Element::hasAttributeNS(const String& namespaceURI, const String& localName) const
{
    NamedAttrMap* attrs = attributes(true);
    if (!attrs)
        return false;
    return attrs->getAttributeItem(QualifiedName(nullAtom, localName, namespaceURI));
}

CSSStyleDeclaration *Element::style()
{
    return 0;
}

void Element::focus(bool restorePreviousSelection)
{
    Document* doc = document();
    if (doc->focusedNode() == this)
        return;

    doc->updateLayoutIgnorePendingStylesheets();
    
    if (!supportsFocus())
        return;
    
    if (Page* page = doc->page())
        page->focusController()->setFocusedNode(this, doc->frame());

    if (!isFocusable()) {
        ensureRareData()->setNeedsFocusAppearanceUpdateSoonAfterAttach(true);
        return;
    }
        
    cancelFocusAppearanceUpdate();
    updateFocusAppearance(restorePreviousSelection);
}

void Element::updateFocusAppearance(bool /*restorePreviousSelection*/)
{
    if (this == rootEditableElement()) { 
        Frame* frame = document()->frame();
        if (!frame)
            return;

        // FIXME: We should restore the previous selection if there is one.
        VisibleSelection newSelection = hasTagName(htmlTag) || hasTagName(bodyTag) ? VisibleSelection(Position(this, 0), DOWNSTREAM) : VisibleSelection::selectionFromContentsOfNode(this);
        
        if (frame->shouldChangeSelection(newSelection)) {
            frame->selection()->setSelection(newSelection);
            frame->revealSelection();
        }
    }
    // FIXME: I'm not sure all devices will want this off, but this is
    // currently turned off for Andriod.
#if !ENABLE(DIRECTIONAL_PAD_NAVIGATION)
    else if (renderer() && !renderer()->isWidget())
        renderer()->enclosingLayer()->scrollRectToVisible(getRect());
#endif
}

void Element::blur()
{
    cancelFocusAppearanceUpdate();
    Document* doc = document();
    if (doc->focusedNode() == this) {
        if (doc->frame())
            doc->frame()->page()->focusController()->setFocusedNode(0, doc->frame());
        else
            doc->setFocusedNode(0);
    }
}

String Element::innerText() const
{
    // We need to update layout, since plainText uses line boxes in the render tree.
    document()->updateLayoutIgnorePendingStylesheets();

    if (!renderer())
        return textContent(true);

    return plainText(rangeOfContents(const_cast<Element*>(this)).get());
}

String Element::outerText() const
{
    // Getting outerText is the same as getting innerText, only
    // setting is different. You would think this should get the plain
    // text for the outer range, but this is wrong, <br> for instance
    // would return different values for inner and outer text by such
    // a rule, but it doesn't in WinIE, and we want to match that.
    return innerText();
}

String Element::title() const
{
    return String();
}

IntSize Element::minimumSizeForResizing() const
{
    return hasRareData() ? rareData()->m_minimumSizeForResizing : defaultMinimumSizeForResizing();
}

void Element::setMinimumSizeForResizing(const IntSize& size)
{
    if (size == defaultMinimumSizeForResizing() && !hasRareData())
        return;
    ensureRareData()->m_minimumSizeForResizing = size;
}

RenderStyle* Element::computedStyle()
{
    if (RenderStyle* usedStyle = renderStyle())
        return usedStyle;

    if (!attached())
        // FIXME: Try to do better than this. Ensure that styleForElement() works for elements that are not in the
        // document tree and figure out when to destroy the computed style for such elements.
        return 0;

    ElementRareData* data = ensureRareData();
    if (!data->m_computedStyle)
        data->m_computedStyle = document()->styleSelector()->styleForElement(this, parent() ? parent()->computedStyle() : 0);
    return data->m_computedStyle.get();
}

void Element::cancelFocusAppearanceUpdate()
{
    if (hasRareData())
        rareData()->setNeedsFocusAppearanceUpdateSoonAfterAttach(false);
    if (document()->focusedNode() == this)
        document()->cancelFocusAppearanceUpdate();
}

void Element::normalizeAttributes()
{
    // Normalize attributes.
    NamedAttrMap* attrs = attributes(true);
    if (!attrs)
        return;
    unsigned numAttrs = attrs->length();
    for (unsigned i = 0; i < numAttrs; i++) {
        if (Attr* attr = attrs->attributeItem(i)->attr())
            attr->normalize();
    }
}

// ElementTraversal API
Element* Element::firstElementChild() const
{
    Node* n = firstChild();
    while (n && !n->isElementNode())
        n = n->nextSibling();
    return static_cast<Element*>(n);
}

Element* Element::lastElementChild() const
{
    Node* n = lastChild();
    while (n && !n->isElementNode())
        n = n->previousSibling();
    return static_cast<Element*>(n);
}

Element* Element::previousElementSibling() const
{
    Node* n = previousSibling();
    while (n && !n->isElementNode())
        n = n->previousSibling();
    return static_cast<Element*>(n);
}

Element* Element::nextElementSibling() const
{
    Node* n = nextSibling();
    while (n && !n->isElementNode())
        n = n->nextSibling();
    return static_cast<Element*>(n);
}

unsigned Element::childElementCount() const
{
    unsigned count = 0;
    Node* n = firstChild();
    while (n) {
        count += n->isElementNode();
        n = n->nextSibling();
    }
    return count;
}

}