Source/WebCore/dom/MutationObserverInterestGroup.h

/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * in the documentation and/or other materials provided with the
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 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#pragma once

#include "DocumentInlines.h"
#include "MutationObserver.h"
#include <memory>
#include <wtf/HashMap.h>

namespace WebCore {

class QualifiedName;

class MutationObserverInterestGroup {
    WTF_MAKE_FAST_ALLOCATED;
public:
    MutationObserverInterestGroup(HashMap<Ref<MutationObserver>, MutationRecordDeliveryOptions>&&, MutationRecordDeliveryOptions);

    static std::unique_ptr<MutationObserverInterestGroup> createForChildListMutation(Node& target)
    {
        if (!target.document().hasMutationObserversOfType(MutationObserverOptionType::ChildList))
            return nullptr;

        MutationRecordDeliveryOptions oldValueFlag;
        return createIfNeeded(target, MutationObserverOptionType::ChildList, oldValueFlag);
    }

    static std::unique_ptr<MutationObserverInterestGroup> createForCharacterDataMutation(Node& target)
    {
        if (!target.document().hasMutationObserversOfType(MutationObserverOptionType::CharacterData))
            return nullptr;

        return createIfNeeded(target, MutationObserverOptionType::CharacterData, MutationObserverOptionType::CharacterDataOldValue);
    }

    static std::unique_ptr<MutationObserverInterestGroup> createForAttributesMutation(Node& target, const QualifiedName& attributeName)
    {
        if (!target.document().hasMutationObserversOfType(MutationObserverOptionType::Attributes))
            return nullptr;

        return createIfNeeded(target, MutationObserverOptionType::Attributes, MutationObserverOptionType::AttributeOldValue, &attributeName);
    }

    bool isOldValueRequested() const;
    void enqueueMutationRecord(Ref<MutationRecord>&&);

private:
    static std::unique_ptr<MutationObserverInterestGroup> createIfNeeded(Node& target, MutationObserverOptionType, MutationRecordDeliveryOptions oldValueFlag, const QualifiedName* attributeName = nullptr);

    bool hasOldValue(MutationRecordDeliveryOptions options) const { return options.containsAny(m_oldValueFlag); }

    HashMap<Ref<MutationObserver>, MutationRecordDeliveryOptions> m_observers;
    MutationRecordDeliveryOptions m_oldValueFlag;
};

} // namespace WebCore