Source/WebCore/dom/MutationObserverRegistration.h

/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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#pragma once

#include "GCReachableRef.h"
#include "MutationObserver.h"
#include <wtf/HashSet.h>
#include <wtf/text/AtomicString.h>
#include <wtf/text/AtomicStringHash.h>

namespace WebCore {

class QualifiedName;

class MutationObserverRegistration {
    WTF_MAKE_FAST_ALLOCATED;
public:
    MutationObserverRegistration(MutationObserver&, Node&, MutationObserverOptions, const HashSet<AtomicString>& attributeFilter);
    ~MutationObserverRegistration();

    void resetObservation(MutationObserverOptions, const HashSet<AtomicString>& attributeFilter);
    void observedSubtreeNodeWillDetach(Node&);
    std::unique_ptr<HashSet<GCReachableRef<Node>>> takeTransientRegistrations();
    bool hasTransientRegistrations() const { return m_transientRegistrationNodes && !m_transientRegistrationNodes->isEmpty(); }

    bool shouldReceiveMutationFrom(Node&, MutationObserver::MutationType, const QualifiedName* attributeName) const;
    bool isSubtree() const { return m_options & MutationObserver::Subtree; }

    MutationObserver& observer() { return m_observer.get(); }
    Node& node() { return m_node; }
    MutationRecordDeliveryOptions deliveryOptions() const { return m_options & (MutationObserver::AttributeOldValue | MutationObserver::CharacterDataOldValue); }
    MutationObserverOptions mutationTypes() const { return m_options & MutationObserver::AllMutationTypes; }

    void addRegistrationNodesToSet(HashSet<Node*>&) const;

private:
    Ref<MutationObserver> m_observer;
    Node& m_node;
    RefPtr<Node> m_nodeKeptAlive;
    std::unique_ptr<HashSet<GCReachableRef<Node>>> m_transientRegistrationNodes;
    MutationObserverOptions m_options;
    HashSet<AtomicString> m_attributeFilter;
};

} // namespace WebCore