Source/core/dom/EventPathWalker.cpp

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
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 *
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#include "config.h"
#include "core/dom/EventPathWalker.h"

#include "core/dom/shadow/ContentDistributor.h"
#include "core/dom/shadow/InsertionPoint.h"
#include "core/dom/shadow/ShadowRoot.h"

namespace WebCore {

EventPathWalker::EventPathWalker(const Node* node)
    : m_node(node)
    , m_distributedNode(node)
    , m_isVisitingInsertionPointInReprojection(false)
{
    ASSERT(node);
    // FIXME: It's not clear if we need this document check, but I think we do
    // since DocType nodes from document.implementation.createDocumentType
    // don't have a document().
    if (Document* document = node->document())
        document->updateDistributionForNodeIfNeeded(const_cast<Node*>(node));
}

Node* EventPathWalker::parent(const Node* node)
{
    EventPathWalker walker(node);
    walker.moveToParent();
    return walker.node();
}

void EventPathWalker::moveToParent()
{
    ASSERT(m_node);
    ASSERT(m_distributedNode);
    if (ElementShadow* shadow = shadowOfParent(m_node)) {
        if (InsertionPoint* insertionPoint = shadow->distributor().findInsertionPointFor(m_distributedNode)) {
            m_node = insertionPoint;
            m_isVisitingInsertionPointInReprojection = true;
            return;
        }
    }
    if (!m_node->isShadowRoot()) {
        m_node = m_node->parentNode();
        if (!(m_node && m_node->isShadowRoot() && toShadowRoot(m_node)->insertionPoint()))
            m_distributedNode = m_node;
        m_isVisitingInsertionPointInReprojection = false;
        return;
    }

    const ShadowRoot* shadowRoot = toShadowRoot(m_node);
    if (InsertionPoint* insertionPoint = shadowRoot->insertionPoint()) {
        m_node = insertionPoint;
        m_isVisitingInsertionPointInReprojection = true;
        return;
    }
    m_node = shadowRoot->host();
    m_distributedNode = m_node;
    m_isVisitingInsertionPointInReprojection = false;
}

} // namespace