/*=============================================================================
    Spirit v1.6.0
    Copyright (c) 2002-2003 Hartmut Kaiser
    http://spirit.sourceforge.net/

    Permission to copy, use, modify, sell and distribute this software is
    granted provided this copyright notice appears in all copies. This
    software is provided "as is" without express or implied warranty, and
    with no claim as to its suitability for any purpose.
=============================================================================*/
#ifndef BOOST_SPIRIT_CONFIX_IPP
#define BOOST_SPIRIT_CONFIX_IPP

///////////////////////////////////////////////////////////////////////////////
#include "boost/spirit/utility/refactoring.hpp"
#include "boost/spirit/core/composite/impl/directives.ipp"

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

///////////////////////////////////////////////////////////////////////////////
//
//  Types to distinguish nested and non-nested confix parsers
//
///////////////////////////////////////////////////////////////////////////////
struct is_nested {};
struct non_nested {};

///////////////////////////////////////////////////////////////////////////////
//
//  Types to distinguish between confix parsers, which are implicitly lexems
//  and without this behaviour
//
///////////////////////////////////////////////////////////////////////////////
struct is_lexeme {};
struct non_lexeme {};

///////////////////////////////////////////////////////////////////////////////
//
//  confix_parser_type class implementation
//
///////////////////////////////////////////////////////////////////////////////
namespace impl {

    ///////////////////////////////////////////////////////////////////////////
    //  implicitly insert a lexeme_d into the parsing process

    template <typename LexemeT>
    struct select_confix_parse_lexeme;

    template <>
    struct select_confix_parse_lexeme<is_lexeme> {

        template <typename ParserT, typename ScannerT>
        static typename parser_result<ParserT, ScannerT>::type
        parse(ParserT const& p, ScannerT const& scan)
        {
            typedef typename parser_result<ParserT, ScannerT>::type result_t;
            return contiguous_parser_parse<result_t>(p, scan, scan);
        }
    };

    template <>
    struct select_confix_parse_lexeme<non_lexeme> {

        template <typename ParserT, typename ScannerT>
        static typename parser_result<ParserT, ScannerT>::type
        parse(ParserT const& p, ScannerT const& scan)
        {
            return p.parse(scan);
        }
    };

    ///////////////////////////////////////////////////////////////////////////
    //  parse confix sequences with refactoring

    template <typename NestedT>
    struct select_confix_parse_refactor;

    template <>
    struct select_confix_parse_refactor<is_nested> {

        template <
            typename LexemeT, typename ParserT, typename ScannerT,
            typename OpenT, typename ExprT, typename CloseT
        >
        static typename parser_result<ParserT, ScannerT>::type
        parse(
            LexemeT const &, ParserT const& this_, ScannerT const& scan,
            OpenT const& open, ExprT const& expr, CloseT const& close)
        {
            typedef refactor_action_gen<refactor_unary_gen<> > refactor_t;
            const refactor_t refactor_body_d = refactor_t(refactor_unary_d);

            return select_confix_parse_lexeme<LexemeT>::parse((
                            open
                        >>  this_ | refactor_body_d[expr - close]
                        >>  close
                    ),  scan);
        }
    };

    template <>
    struct select_confix_parse_refactor<non_nested> {

        template <
            typename LexemeT, typename ParserT, typename ScannerT,
            typename OpenT, typename ExprT, typename CloseT
        >
        static typename parser_result<ParserT, ScannerT>::type
        parse(
            LexemeT const &, ParserT const& /*this_*/, ScannerT const& scan,
            OpenT const& open, ExprT const& expr, CloseT const& close)
        {
            typedef refactor_action_gen<refactor_unary_gen<> > refactor_t;
            const refactor_t refactor_body_d = refactor_t(refactor_unary_d);

            return select_confix_parse_lexeme<LexemeT>::parse((
                            open
                        >>  refactor_body_d[expr - close]
                        >>  close
                    ),  scan);
        }
    };

    ///////////////////////////////////////////////////////////////////////////
    //  parse confix sequences without refactoring

    template <typename NestedT>
    struct select_confix_parse_no_refactor;

    template <>
    struct select_confix_parse_no_refactor<is_nested> {

        template <
            typename LexemeT, typename ParserT, typename ScannerT,
            typename OpenT, typename ExprT, typename CloseT
        >
        static typename parser_result<ParserT, ScannerT>::type
        parse(
            LexemeT const &, ParserT const& this_, ScannerT const& scan,
            OpenT const& open, ExprT const& expr, CloseT const& close)
        {
            return select_confix_parse_lexeme<LexemeT>::parse((
                            open
                        >>  this_ | (expr - close)
                        >>  close
                    ),  scan);
        }
    };

    template <>
    struct select_confix_parse_no_refactor<non_nested> {

        template <
            typename LexemeT, typename ParserT, typename ScannerT,
            typename OpenT, typename ExprT, typename CloseT
        >
        static typename parser_result<ParserT, ScannerT>::type
        parse(
            LexemeT const &, ParserT const & /*this_*/, ScannerT const& scan,
            OpenT const& open, ExprT const& expr, CloseT const& close)
        {
            return select_confix_parse_lexeme<LexemeT>::parse((
                            open
                        >>  (expr - close)
                        >>  close
                    ),  scan);
        }
    };

    // the refactoring is handled by the refactoring parsers, so here there
    // is no need to pay attention to these issues.

    template <typename CategoryT>
    struct confix_parser_type {

        template <
            typename NestedT, typename LexemeT,
            typename ParserT, typename ScannerT,
            typename OpenT, typename ExprT, typename CloseT
        >
        static typename parser_result<ParserT, ScannerT>::type
        parse(
            NestedT const &, LexemeT const &lexeme,
            ParserT const& this_, ScannerT const& scan,
            OpenT const& open, ExprT const& expr, CloseT const& close)
        {
            return select_confix_parse_refactor<NestedT>::
                parse(lexeme, this_, scan, open, expr, close);
        }
    };

    template <>
    struct confix_parser_type<plain_parser_category> {

        template <
            typename NestedT, typename LexemeT,
            typename ParserT, typename ScannerT,
            typename OpenT, typename ExprT, typename CloseT
        >
        static typename parser_result<ParserT, ScannerT>::type
        parse(
            NestedT const &, LexemeT const &lexeme,
            ParserT const& this_, ScannerT const& scan,
            OpenT const& open, ExprT const& expr, CloseT const& close)
        {
            return select_confix_parse_no_refactor<NestedT>::
                parse(lexeme, this_, scan, open, expr, close);
        }
    };

}   // namespace impl

///////////////////////////////////////////////////////////////////////////////
}} // namespace boost::spirit

#endif

