Source/core/dom/shadow/InsertionPoint.cpp

/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * in the documentation and/or other materials provided with the
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#include "config.h"
#include "core/dom/shadow/InsertionPoint.h"

#include "HTMLNames.h"
#include "core/dom/QualifiedName.h"
#include "core/dom/StaticNodeList.h"
#include "core/dom/shadow/ElementShadow.h"
#include "core/dom/shadow/ShadowRoot.h"

namespace WebCore {

using namespace HTMLNames;

InsertionPoint::InsertionPoint(const QualifiedName& tagName, Document* document)
    : HTMLElement(tagName, document, CreateInsertionPoint)
    , m_registeredWithShadowRoot(false)
{
    setHasCustomStyleCallbacks();
}

InsertionPoint::~InsertionPoint()
{
}

void InsertionPoint::attach(const AttachContext& context)
{
    if (ShadowRoot* shadowRoot = containingShadowRoot())
        shadowRoot->host()->ensureDistribution();
    for (size_t i = 0; i < m_distribution.size(); ++i) {
        if (!m_distribution.at(i)->attached())
            m_distribution.at(i)->attach(context);
    }

    HTMLElement::attach(context);
}

void InsertionPoint::detach(const AttachContext& context)
{
    if (ShadowRoot* shadowRoot = containingShadowRoot())
        shadowRoot->host()->ensureDistribution();

    for (size_t i = 0; i < m_distribution.size(); ++i)
        m_distribution.at(i)->detach(context);

    HTMLElement::detach(context);
}

void InsertionPoint::willRecalcStyle(StyleChange change)
{
    if (change < Inherit)
        return;
    if (ShadowRoot* shadowRoot = containingShadowRoot()) {
        shadowRoot->host()->ensureDistribution();
        shadowRoot->owner()->distributor().setNeedsStyleRecalcIfDistributedTo(this);
    }
}

bool InsertionPoint::shouldUseFallbackElements() const
{
    return isActive() && !hasDistribution();
}

bool InsertionPoint::isActive() const
{
    if (!containingShadowRoot())
        return false;
    const Node* node = parentNode();
    while (node) {
        if (node->isInsertionPoint())
            return false;

        node = node->parentNode();
    }
    return true;
}

PassRefPtr<NodeList> InsertionPoint::getDistributedNodes() const
{
    if (ShadowRoot* shadowRoot = containingShadowRoot())
        shadowRoot->host()->ensureDistribution();

    Vector<RefPtr<Node> > nodes;

    for (size_t i = 0; i < m_distribution.size(); ++i)
        nodes.append(m_distribution.at(i));

    return StaticNodeList::adopt(nodes);
}

bool InsertionPoint::rendererIsNeeded(const NodeRenderingContext& context)
{
    return !isActive() && HTMLElement::rendererIsNeeded(context);
}

void InsertionPoint::childrenChanged(bool changedByParser, Node* beforeChange, Node* afterChange, int childCountDelta)
{
    HTMLElement::childrenChanged(changedByParser, beforeChange, afterChange, childCountDelta);
    if (ShadowRoot* root = containingShadowRoot())
        if (ElementShadow* rootOwner = root->owner())
            rootOwner->invalidateDistribution();
}

Node::InsertionNotificationRequest InsertionPoint::insertedInto(ContainerNode* insertionPoint)
{
    HTMLElement::insertedInto(insertionPoint);

    if (ShadowRoot* root = containingShadowRoot()) {
        if (ElementShadow* rootOwner = root->owner()) {
            rootOwner->distributor().didShadowBoundaryChange(root->host());
            if (isActive() && !m_registeredWithShadowRoot && insertionPoint->treeScope()->rootNode() == root) {
                m_registeredWithShadowRoot = true;
                root->ensureScopeDistribution()->registerInsertionPoint(this);
                if (canAffectSelector())
                    rootOwner->willAffectSelector();
            }
        }
    }

    return InsertionDone;
}

void InsertionPoint::removedFrom(ContainerNode* insertionPoint)
{
    ShadowRoot* root = containingShadowRoot();
    if (!root)
        root = insertionPoint->containingShadowRoot();

    // host can be null when removedFrom() is called from ElementShadow destructor.
    ElementShadow* rootOwner = root ? root->owner() : 0;
    if (rootOwner)
        rootOwner->invalidateDistribution();

    // Since this insertion point is no longer visible from the shadow subtree, it need to clean itself up.
    clearDistribution();

    if (m_registeredWithShadowRoot && insertionPoint->treeScope()->rootNode() == root) {
        ASSERT(root);
        m_registeredWithShadowRoot = false;
        root->ensureScopeDistribution()->unregisterInsertionPoint(this);
        if (rootOwner && canAffectSelector())
            rootOwner->willAffectSelector();
    }

    HTMLElement::removedFrom(insertionPoint);
}

void InsertionPoint::parseAttribute(const QualifiedName& name, const AtomicString& value)
{
    if (name == reset_style_inheritanceAttr) {
        if (!inDocument() || !attached() || !isActive())
            return;
        containingShadowRoot()->host()->setNeedsStyleRecalc();
    } else
        HTMLElement::parseAttribute(name, value);
}

bool InsertionPoint::resetStyleInheritance() const
{
    return fastHasAttribute(reset_style_inheritanceAttr);
}

void InsertionPoint::setResetStyleInheritance(bool value)
{
    setBooleanAttribute(reset_style_inheritanceAttr, value);
}

bool InsertionPoint::contains(const Node* node) const
{
    return m_distribution.contains(const_cast<Node*>(node)) || (node->isShadowRoot() && toShadowRoot(node)->insertionPoint() == this);
}

const CSSSelectorList& InsertionPoint::emptySelectorList()
{
    DEFINE_STATIC_LOCAL(CSSSelectorList, selectorList, (CSSSelectorList()));
    return selectorList;
}

InsertionPoint* resolveReprojection(const Node* projectedNode)
{
    InsertionPoint* insertionPoint = 0;
    const Node* current = projectedNode;

    while (current) {
        if (ElementShadow* shadow = shadowOfParentForDistribution(current)) {
            shadow->host()->ensureDistribution();
            if (ShadowRoot* root = current->containingShadowRoot())
                root->host()->ensureDistribution();
            if (InsertionPoint* insertedTo = shadow->distributor().findInsertionPointFor(projectedNode)) {
                current = insertedTo;
                insertionPoint = insertedTo;
                continue;
            }
        }

        if (Node* parent = parentNodeForDistribution(current)) {
            if (InsertionPoint* insertedTo = parent->isShadowRoot() ? toShadowRoot(parent)->insertionPoint() : 0) {
                current = insertedTo;
                insertionPoint = insertedTo;
                continue;
            }
        }

        break;
    }

    return insertionPoint;
}

void collectInsertionPointsWhereNodeIsDistributed(const Node* node, Vector<InsertionPoint*, 8>& results)
{
    const Node* current = node;
    while (true) {
        if (ElementShadow* shadow = shadowOfParentForDistribution(current)) {
            if (ShadowRoot* root = current->containingShadowRoot())
                root->host()->ensureDistribution();
            if (InsertionPoint* insertedTo = shadow->distributor().findInsertionPointFor(node)) {
                current = insertedTo;
                results.append(insertedTo);
                continue;
            }
        }
        if (Node* parent = parentNodeForDistribution(current)) {
            if (InsertionPoint* insertedTo = parent->isShadowRoot() ? toShadowRoot(parent)->insertionPoint() : 0) {
                current = insertedTo;
                results.append(insertedTo);
                continue;
            }
        }
        return;
    }
}

} // namespace WebCore