/*=============================================================================
    Copyright (c) 2003 Martin Wille
    http://spirit.sourceforge.net/

    Use, modification and distribution is subject to 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)
 =============================================================================*/
#ifndef BOOST_SPIRIT_UTILITY_SCOPED_LOCK_HPP
#define BOOST_SPIRIT_UTILITY_SCOPED_LOCK_HPP

///////////////////////////////////////////////////////////////////////////////
#if !defined(BOOST_SPIRIT_COMPOSITE_HPP)
#include <boost/spirit/core/composite.hpp>
#endif

///////////////////////////////////////////////////////////////////////////////
namespace boost { namespace spirit {

    ///////////////////////////////////////////////////////////////////////////
    //
    // scoped_lock_parser class
    //
    //      implements locking of a mutex during execution of
    //      the parse method of an embedded parser
    //
    ///////////////////////////////////////////////////////////////////////////
    template <typename MutexT, typename ParserT>
    struct scoped_lock_parser
        : public unary< ParserT, parser< scoped_lock_parser<MutexT, ParserT> > >
    {
        typedef scoped_lock_parser<MutexT, ParserT> self_t;
        typedef MutexT      mutex_t;
        typedef ParserT     parser_t;

        template <typename ScannerT>
        struct result
        {
            typedef typename parser_result<parser_t, ScannerT>::type type;
        };

        scoped_lock_parser(mutex_t &m, parser_t const &p)
            : unary< ParserT, parser< scoped_lock_parser<MutexT, ParserT> > >(p)
            , mutex(m)
        {}


        template <typename ScannerT>
        typename parser_result<self_t, ScannerT>::type
        parse(ScannerT const &scan) const
        {
            typedef typename  mutex_t::scoped_lock scoped_lock_t;
            scoped_lock_t lock(mutex);
            return this->subject().parse(scan);
        }

        mutex_t &mutex;
    };

    ///////////////////////////////////////////////////////////////////////////
    //
    // scoped_lock_parser_gen
    //
    //      generator for scoped_lock_parser objects
    //      operator[] returns scoped_lock_parser according to its argument
    //
    ///////////////////////////////////////////////////////////////////////////
    template <typename MutexT>
    struct scoped_lock_parser_gen
    {
        typedef MutexT mutex_t;
        explicit scoped_lock_parser_gen(mutex_t &m) : mutex(m) {}

        template<typename ParserT>
        scoped_lock_parser
        <
            MutexT,
            typename as_parser<ParserT>::type
        >
        operator[](ParserT const &p) const
        {
            typedef ::boost::spirit::as_parser<ParserT> as_parser_t;
            typedef typename as_parser_t::type parser_t;

            return scoped_lock_parser<mutex_t, parser_t>
                (mutex, as_parser_t::convert(p));
        }

        mutex_t &mutex;
    };


    ///////////////////////////////////////////////////////////////////////////
    //
    // scoped_lock_d parser directive
    //
    //      constructs a scoped_lock_parser generator from its argument
    //
    ///////////////////////////////////////////////////////////////////////////
    template <typename MutexT>
    scoped_lock_parser_gen<MutexT>
    scoped_lock_d(MutexT &mutex)
    {
        return scoped_lock_parser_gen<MutexT>(mutex);
    }

}} // namespace boost::spirit
#endif // BOOST_SPIRIT_UTILITY_SCOPED_LOCK_HPP
