// -*- c-basic-offset: 2 -*-

/*

 *  This file is part of the KDE libraries

 *  Copyright (C) 2004 Apple Computer, Inc.

 *

 *  This library is free software; you can redistribute it and/or

 *  modify it under the terms of the GNU Library General Public

 *  License as published by the Free Software Foundation; either

 *  version 2 of the License, or (at your option) any later version.

 *

 *  This library is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 *  Library General Public License for more details.

 *

 *  You should have received a copy of the GNU Library General Public License

 *  along with this library; see the file COPYING.LIB.  If not, write to

 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

 *  Boston, MA 02110-1301, USA.

 *

 */

#ifndef _KJS_PROTECT_H_

#define _KJS_PROTECT_H_

#include "value.h"

#include "collector.h"

#include "JSLock.h"

namespace KJS {

    inline void gcProtect(JSValue *val) 

    { 

        Collector::protect(val);

    }

    inline void gcUnprotect(JSValue *val)

    { 

        Collector::unprotect(val);

    }

    inline void gcProtectNullTolerant(JSValue *val) 

    {

        if (val) 

            gcProtect(val);

    }

    inline void gcUnprotectNullTolerant(JSValue *val) 

    {

        if (val) 

            gcUnprotect(val);

    }

    // FIXME: Share more code with RefPtr template? The only differences are the ref/deref operation

    // and the implicit conversion to raw pointer

    template <class T> class ProtectedPtr {

    public:

        ProtectedPtr() : m_ptr(NULL) { }

        ProtectedPtr(T *ptr);

        ProtectedPtr(const ProtectedPtr &);

        ~ProtectedPtr();

        template <class U> ProtectedPtr(const ProtectedPtr<U> &);

        T *get() const { return m_ptr; }

        operator T *() const { return m_ptr; }

        T *operator->() const { return m_ptr; }

        bool operator!() const { return m_ptr == NULL; }

        ProtectedPtr &operator=(const ProtectedPtr &);

        ProtectedPtr &operator=(T *);

    private:

        T *m_ptr;

    };

    template <class T> ProtectedPtr<T>::ProtectedPtr(T *ptr)

        : m_ptr(ptr)

    {

        if (ptr) {

            JSLock lock;

            gcProtect(ptr);

        }

    }

    template <class T> ProtectedPtr<T>::ProtectedPtr(const ProtectedPtr &o)

        : m_ptr(o.get())

    {

        if (T *ptr = m_ptr) {

            JSLock lock;

            gcProtect(ptr);

        }

    }

    template <class T> ProtectedPtr<T>::~ProtectedPtr()

    {

        if (T *ptr = m_ptr) {

            JSLock lock;

            gcUnprotect(ptr);

        }

    }

    template <class T> template <class U> ProtectedPtr<T>::ProtectedPtr(const ProtectedPtr<U> &o)

        : m_ptr(o.get())

    {

        if (T *ptr = m_ptr) {

            JSLock lock;

            gcProtect(ptr);

        }

    }

    template <class T> ProtectedPtr<T> &ProtectedPtr<T>::operator=(const ProtectedPtr<T> &o) 

    {

        JSLock lock;

        T *optr = o.m_ptr;

        gcProtectNullTolerant(optr);

        gcUnprotectNullTolerant(m_ptr);

        m_ptr = optr;

         return *this;

     }

    template <class T> inline ProtectedPtr<T> &ProtectedPtr<T>::operator=(T *optr)

    {

        JSLock lock;

        gcProtectNullTolerant(optr);

        gcUnprotectNullTolerant(m_ptr);

        m_ptr = optr;

        return *this;

    }

    template <class T> inline bool operator==(const ProtectedPtr<T> &a, const ProtectedPtr<T> &b) { return a.get() == b.get(); }

    template <class T> inline bool operator==(const ProtectedPtr<T> &a, const T *b) { return a.get() == b; }

    template <class T> inline bool operator==(const T *a, const ProtectedPtr<T> &b) { return a == b.get(); }

    template <class T> inline bool operator!=(const ProtectedPtr<T> &a, const ProtectedPtr<T> &b) { return a.get() != b.get(); }

    template <class T> inline bool operator!=(const ProtectedPtr<T> &a, const T *b) { return a.get() != b; }

    template <class T> inline bool operator!=(const T *a, const ProtectedPtr<T> &b) { return a != b.get(); }

} // namespace

#endif