// -*- mode: c++; c-basic-offset: 4 -*-

/*

 * Copyright (C) 2008 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.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 COMPUTER, INC. OR

 * 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 JSTypeInfo_h

#define JSTypeInfo_h

// This file would be called TypeInfo.h, but that conflicts with <typeinfo.h>

// in the STL on systems without case-sensitive file systems. 

#include "JSType.h"

namespace JSC {

    // WebCore uses MasqueradesAsUndefined to make document.all and style.filter undetectable.

    static const unsigned MasqueradesAsUndefined = 1;

    static const unsigned ImplementsHasInstance = 1 << 1;

    static const unsigned OverridesHasInstance = 1 << 2;

    static const unsigned ImplementsDefaultHasInstance = 1 << 3;

    static const unsigned NeedsThisConversion = 1 << 4;

    static const unsigned OverridesGetOwnPropertySlot = 1 << 5;

    static const unsigned OverridesMarkChildren = 1 << 6;

    static const unsigned OverridesGetPropertyNames = 1 << 7;

    class TypeInfo {

        friend class JIT;

    public:

        TypeInfo(JSType type, unsigned flags = 0)

            : m_type(type)

        {

            ASSERT(flags <= 0xFF);

            ASSERT(type <= 0xFF);

            // ImplementsDefaultHasInstance means (ImplementsHasInstance & !OverridesHasInstance)

            if ((flags & (ImplementsHasInstance | OverridesHasInstance)) == ImplementsHasInstance)

                m_flags = flags | ImplementsDefaultHasInstance;

            else

                m_flags = flags;

        }

        JSType type() const { return (JSType)m_type; }

        bool masqueradesAsUndefined() const { return m_flags & MasqueradesAsUndefined; }

        bool implementsHasInstance() const { return m_flags & ImplementsHasInstance; }

        bool overridesHasInstance() const { return m_flags & OverridesHasInstance; }

        bool needsThisConversion() const { return m_flags & NeedsThisConversion; }

        bool overridesGetOwnPropertySlot() const { return m_flags & OverridesGetOwnPropertySlot; }

        bool overridesMarkChildren() const { return m_flags & OverridesMarkChildren; }

        bool overridesGetPropertyNames() const { return m_flags & OverridesGetPropertyNames; }

        unsigned flags() const { return m_flags; }

    private:

        unsigned char m_type;

        unsigned char m_flags;

    };

}

#endif // JSTypeInfo_h