Source/WebCore/html/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 "InsertionPoint.h"

#include "HTMLNames.h"
#include "QualifiedName.h"
#include "ShadowRoot.h"
#include "StaticNodeList.h"
#include "Text.h"

namespace WebCore {

using namespace HTMLNames;

InsertionPoint::InsertionPoint(const QualifiedName& tagName, Document& document)
    : HTMLElement(tagName, document, CreateInsertionPoint)
    , m_hasDistribution(false)
{
    setHasCustomStyleResolveCallbacks();
}

InsertionPoint::~InsertionPoint()
{
}

void InsertionPoint::willAttachRenderers()
{
    if (ShadowRoot* shadowRoot = containingShadowRoot())
        ContentDistributor::ensureDistribution(shadowRoot);
    for (Node* current = firstDistributed(); current; current = nextDistributedTo(current)) {
        if (current->attached())
            continue;
        if (current->isTextNode()) {
            Style::attachTextRenderer(*toText(current));
            continue;
        }
        if (current->isElementNode())
            Style::attachRenderTree(*toElement(current));
    }
}

void InsertionPoint::willDetachRenderers()
{
    if (ShadowRoot* shadowRoot = containingShadowRoot())
        ContentDistributor::ensureDistribution(shadowRoot);

    for (Node* current = firstDistributed(); current; current = nextDistributedTo(current)) {
        if (current->isTextNode()) {
            Style::detachTextRenderer(*toText(current));
            continue;
        }
        if (current->isElementNode())
            Style::detachRenderTree(*toElement(current));
    }
}

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;
}

bool InsertionPoint::rendererIsNeeded(const RenderStyle& style)
{
    return !isActive() && HTMLElement::rendererIsNeeded(style);
}

void InsertionPoint::childrenChanged(const ChildChange& change)
{
    HTMLElement::childrenChanged(change);
    if (ShadowRoot* root = containingShadowRoot())
        root->invalidateDistribution();
}

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

    if (ShadowRoot* root = containingShadowRoot()) {
        root->distributor().didShadowBoundaryChange(root->hostElement());
        root->distributor().invalidateInsertionPointList();
    }

    return InsertionDone;
}

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

    if (root && root->hostElement()) {
        root->invalidateDistribution();
        root->distributor().invalidateInsertionPointList();
    }

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

    HTMLElement::removedFrom(insertionPoint);
}
    
Node* InsertionPoint::firstDistributed() const
{
    if (!m_hasDistribution)
        return 0;
    for (Node* current = shadowHost()->firstChild(); current; current = current->nextSibling()) {
        if (matchTypeFor(current) == InsertionPoint::AlwaysMatches)
            return current;
    }
    return 0;
}

Node* InsertionPoint::lastDistributed() const
{
    if (!m_hasDistribution)
        return 0;
    for (Node* current = shadowHost()->lastChild(); current; current = current->previousSibling()) {
        if (matchTypeFor(current) == InsertionPoint::AlwaysMatches)
            return current;
    }
    return 0;
}

Node* InsertionPoint::nextDistributedTo(const Node* node) const
{
    for (Node* current = node->nextSibling(); current; current = current->nextSibling()) {
        if (matchTypeFor(current) == InsertionPoint::AlwaysMatches)
            return current;
    }
    return 0;
}

Node* InsertionPoint::previousDistributedTo(const Node* node) const
{
    for (Node* current = node->previousSibling(); current; current = current->previousSibling()) {
        if (matchTypeFor(current) == InsertionPoint::AlwaysMatches)
            return current;
    }
    return 0;
}

InsertionPoint* findInsertionPointOf(const Node* projectedNode)
{
    if (ShadowRoot* shadowRoot = shadowRootOfParentForDistribution(projectedNode)) {
        if (ShadowRoot* root = projectedNode->containingShadowRoot())
            ContentDistributor::ensureDistribution(root);
        return shadowRoot->distributor().findInsertionPointFor(projectedNode);
    }
    return 0;
}

} // namespace WebCore