// (C) Copyright Thorsten Ottosen 2005.

// (C) Copyright Jonathan Turkanis 2004.

// (C) Copyright Daniel Wallin 2004.

// Distributed under the Boost Software License, Version 1.0. (See accompanying

// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)

// Implementation of the move_ptr from the "Move Proposal" 

// (http://std.dkuug.dk/jtc1/sc22/wg21/docs/papers/2002/n1377.htm) 

// enhanced to support custom deleters and safe boolean conversions.

//

// The implementation is based on an implementation by Daniel Wallin, at

// "http://aspn.activestate.com/ASPN/Mail/Message/Attachments/boost/

// 400DC271.1060903@student.umu.se/move_ptr.hpp". The current was adapted 

// by Jonathan Turkanis to incorporating ideas of Howard Hinnant and 

// Rani Sharoni. 

#ifndef BOOST_STATIC_MOVE_PTR_HPP_INCLUDED

#define BOOST_STATIC_MOVE_PTR_HPP_INCLUDED

#include <boost/config.hpp> // Member template friends, put size_t in std.

#include <algorithm>        // swap.

#include <cstddef>          // size_t

#include <boost/compressed_pair.hpp> 

#include <boost/ptr_container/detail/default_deleter.hpp>       

#include <boost/ptr_container/detail/is_convertible.hpp>       

#include <boost/ptr_container/detail/move.hpp>       

#include <boost/static_assert.hpp>

#include <boost/type_traits/add_reference.hpp>

#include <boost/type_traits/is_array.hpp>

#if defined(BOOST_MSVC)

#pragma warning(push)

#pragma warning(disable:4521)        // Multiple copy constuctors.

#endif

namespace boost { namespace ptr_container_detail {

template< typename T, 

          typename Deleter = 

              move_ptrs::default_deleter<T> >

class static_move_ptr 

{

public:

    typedef typename remove_bounds<T>::type             element_type;

    typedef Deleter                                     deleter_type;

private:

    struct safe_bool_helper { int x; };

    typedef int safe_bool_helper::* safe_bool;

    typedef boost::compressed_pair<element_type*, Deleter> impl_type;

public:

    typedef typename impl_type::second_reference        deleter_reference;

    typedef typename impl_type::second_const_reference  deleter_const_reference;

        // Constructors

    static_move_ptr() : impl_(0) { }

    static_move_ptr(const static_move_ptr& p)

        : impl_(p.get(), p.get_deleter())    

        { 

            const_cast<static_move_ptr&>(p).release();

        }

#if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))    

    static_move_ptr( const move_ptrs::move_source<static_move_ptr<T,Deleter> >& src )

#else

    static_move_ptr( const move_ptrs::move_source<static_move_ptr>& src )

#endif    

            : impl_(src.ptr().get(), src.ptr().get_deleter())

            {

                src.ptr().release();

            }

    template<typename TT>

    explicit static_move_ptr(TT* tt) 

        : impl_(tt, Deleter()) 

        { }

        // Destructor

    ~static_move_ptr() { if (ptr()) get_deleter()(ptr()); }

        // Assignment

    static_move_ptr& operator=(static_move_ptr rhs)

        {

            rhs.swap(*this);

            return *this;

        }

        // Smart pointer interface

    element_type* get() const { return ptr(); }

    element_type& operator*() 

        { 

            /*BOOST_STATIC_ASSERT(!is_array);*/ return *ptr(); 

        }

    const element_type& operator*() const 

        { 

            /*BOOST_STATIC_ASSERT(!is_array);*/ return *ptr(); 

        }

    element_type* operator->()  

        { 

            /*BOOST_STATIC_ASSERT(!is_array);*/ return ptr(); 

        }    

    const element_type* operator->() const 

        { 

            /*BOOST_STATIC_ASSERT(!is_array);*/ return ptr(); 

        }    

    element_type* release()

        {

            element_type* result = ptr();

            ptr() = 0;

            return result;

        }

    void reset()

        {

            if (ptr()) get_deleter()(ptr());

            ptr() = 0;

        }

    template<typename TT>

    void reset(TT* tt) 

        {

            static_move_ptr(tt).swap(*this);

        }

    template<typename TT, typename DD>

    void reset(TT* tt, DD dd) 

        {

            static_move_ptr(tt, dd).swap(*this);

        }

    operator safe_bool() const { return ptr() ? &safe_bool_helper::x : 0; }

    void swap(static_move_ptr& p) { impl_.swap(p.impl_); }

    deleter_reference get_deleter() { return impl_.second(); }

    deleter_const_reference get_deleter() const { return impl_.second(); }

private:

    template<typename TT, typename DD>

    void check(const static_move_ptr<TT, DD>& ptr)

        {

            typedef move_ptrs::is_smart_ptr_convertible<TT, T> convertible;

            BOOST_STATIC_ASSERT(convertible::value);

        }   

#if defined(BOOST_NO_FUNCTION_TEMPLATE_ORDERING) || defined(BOOST_NO_SFINAE)

// give up on this behavior

#else 

    template<typename Ptr> struct cant_move_from_const;

    template<typename TT, typename DD> 

    struct cant_move_from_const< const static_move_ptr<TT, DD> > { 

        typedef typename static_move_ptr<TT, DD>::error type; 

    };

    template<typename Ptr> 

    static_move_ptr(Ptr&, typename cant_move_from_const<Ptr>::type = 0);

public:

    static_move_ptr(static_move_ptr&);

private:

    template<typename TT, typename DD>

    static_move_ptr( static_move_ptr<TT, DD>&,

                     typename 

                     move_ptrs::enable_if_convertible<

                         TT, T, static_move_ptr&

                     >::type::type* = 0 );

#endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING || BOOST_NO_SFINAE

//#ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS

//    template<typename TT, typename DD>

//    friend class static_move_ptr;

//#else

    public:

//#endif

    typename impl_type::first_reference 

    ptr() { return impl_.first(); } 

    typename impl_type::first_const_reference 

    ptr() const { return impl_.first(); }

    impl_type impl_;

};

} // namespace ptr_container_detail

} // End namespace boost.

#if defined(BOOST_MSVC)

#pragma warning(pop) // #pragma warning(disable:4251)

#endif

#endif      // #ifndef BOOST_STATIC_MOVE_PTR_HPP_INCLUDED