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/*
 * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef JSPropertyNameIterator_h
#define JSPropertyNameIterator_h

#include "JSObject.h"
#include "JSString.h"
#include "Operations.h"
#include "PropertyNameArray.h"

namespace JSC {

    class Identifier;
    class JSObject;

    class JSPropertyNameIterator : public JSCell {
        friend class JIT;

    public:
        static JSPropertyNameIterator* create(ExecState*, JSObject*);
        
        static PassRefPtr<Structure> createStructure(JSValue prototype)
        {
            return Structure::create(prototype, TypeInfo(CompoundType, OverridesMarkChildren), AnonymousSlotCount);
        }
        
        virtual ~JSPropertyNameIterator();

        virtual bool isPropertyNameIterator() const { return true; }

        virtual void markChildren(MarkStack&);

        bool getOffset(size_t i, int& offset)
        {
            if (i >= m_numCacheableSlots)
                return false;
            offset = i;
            return true;
        }

        JSValue get(ExecState*, JSObject*, size_t i);
        size_t size() { return m_jsStringsSize; }

        void setCachedStructure(Structure* structure) { m_cachedStructure = structure; }
        Structure* cachedStructure() { return m_cachedStructure; }

        void setCachedPrototypeChain(NonNullPassRefPtr<StructureChain> cachedPrototypeChain) { m_cachedPrototypeChain = cachedPrototypeChain; }
        StructureChain* cachedPrototypeChain() { return m_cachedPrototypeChain.get(); }

    private:
        JSPropertyNameIterator(ExecState*, PropertyNameArrayData* propertyNameArrayData, size_t numCacheableSlot);

        Structure* m_cachedStructure;
        RefPtr<StructureChain> m_cachedPrototypeChain;
        uint32_t m_numCacheableSlots;
        uint32_t m_jsStringsSize;
        OwnArrayPtr<JSValue> m_jsStrings;
    };

    inline void Structure::setEnumerationCache(JSPropertyNameIterator* enumerationCache)
    {
        ASSERT(!isDictionary());
        m_enumerationCache = enumerationCache;
    }

    inline void Structure::clearEnumerationCache(JSPropertyNameIterator* enumerationCache)
    {
        m_enumerationCache.clear(enumerationCache);
    }

    inline JSPropertyNameIterator* Structure::enumerationCache()
    {
        return m_enumerationCache.get();
    }

} // namespace JSC

#endif // JSPropertyNameIterator_h