// Copyright (C) 2004 Arkadiy Vertleyb

// Copyright (C) 2005 Peder Holt

// 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)

#ifndef BOOST_TYPEOF_TEMPLATE_ENCODING_HPP_INCLUDED

#define BOOST_TYPEOF_TEMPLATE_ENCODING_HPP_INCLUDED

#include <boost/preprocessor/cat.hpp>

#include <boost/preprocessor/repetition/enum_trailing.hpp>

#include <boost/preprocessor/control/iif.hpp>

#include <boost/preprocessor/detail/is_unary.hpp>

#include <boost/preprocessor/repetition/repeat.hpp>

#include <boost/preprocessor/tuple/eat.hpp>

#include <boost/preprocessor/seq/transform.hpp>

#include <boost/preprocessor/seq/for_each_i.hpp>

#include <boost/preprocessor/seq/cat.hpp>

#include <boost/typeof/encode_decode.hpp>

#include <boost/typeof/int_encoding.hpp>

#include <boost/typeof/type_template_param.hpp>

#include <boost/typeof/integral_template_param.hpp>

#include <boost/typeof/template_template_param.hpp>

// The template parameter description, entered by the user,

// is converted into a polymorphic "object" 

// that is used to generate the code responsible for

// encoding/decoding the parameter, etc.

// make sure to cat the sequence first, and only then add the prefix.

#define BOOST_TYPEOF_MAKE_OBJ(elem) BOOST_PP_CAT(\

    BOOST_TYPEOF_MAKE_OBJ,\

    BOOST_PP_SEQ_CAT((_) BOOST_TYPEOF_TO_SEQ(elem))\

    )

#define BOOST_TYPEOF_TO_SEQ(tokens) BOOST_TYPEOF_ ## tokens ## _BOOST_TYPEOF 

// BOOST_TYPEOF_REGISTER_TEMPLATE

#define BOOST_TYPEOF_REGISTER_TEMPLATE_EXPLICIT_ID(Name, Params, Id)\

    BOOST_TYPEOF_REGISTER_TEMPLATE_IMPL(\

        Name,\

        BOOST_TYPEOF_MAKE_OBJS(BOOST_TYPEOF_TOSEQ(Params)),\

        BOOST_PP_SEQ_SIZE(BOOST_TYPEOF_TOSEQ(Params)),\

        Id)

#define BOOST_TYPEOF_REGISTER_TEMPLATE(Name, Params)\

    BOOST_TYPEOF_REGISTER_TEMPLATE_EXPLICIT_ID(Name, Params, BOOST_TYPEOF_UNIQUE_ID())

#define BOOST_TYPEOF_OBJECT_MAKER(s, data, elem)\

    BOOST_TYPEOF_MAKE_OBJ(elem)

#define BOOST_TYPEOF_MAKE_OBJS(Params)\

    BOOST_PP_SEQ_TRANSFORM(BOOST_TYPEOF_OBJECT_MAKER, ~, Params)

// As suggested by Paul Mensonides:

#define BOOST_TYPEOF_TOSEQ(x)\

    BOOST_PP_IIF(\

        BOOST_PP_IS_UNARY(x),\

        x BOOST_PP_TUPLE_EAT(3), BOOST_PP_REPEAT\

    )(x, BOOST_TYPEOF_TOSEQ_2, ~)

#define BOOST_TYPEOF_TOSEQ_2(z, n, _) (class)

// BOOST_TYPEOF_VIRTUAL

#define BOOST_TYPEOF_CAT_4(a, b, c, d) BOOST_TYPEOF_CAT_4_I(a, b, c, d)

#define BOOST_TYPEOF_CAT_4_I(a, b, c, d) a ## b ## c ## d

#define BOOST_TYPEOF_VIRTUAL(Fun, Obj)\

    BOOST_TYPEOF_CAT_4(BOOST_TYPEOF_, BOOST_PP_SEQ_HEAD(Obj), _, Fun)

// BOOST_TYPEOF_SEQ_ENUM[_TRAILING][_1]

// Two versions provided due to reentrancy issue

#define BOOST_TYPEOF_SEQ_EXPAND_ELEMENT(z,n,seq)\

   BOOST_PP_SEQ_ELEM(0,seq) (z,n,BOOST_PP_SEQ_ELEM(n,BOOST_PP_SEQ_ELEM(1,seq)))

#define BOOST_TYPEOF_SEQ_ENUM(seq,macro)\

    BOOST_PP_ENUM(BOOST_PP_SEQ_SIZE(seq),BOOST_TYPEOF_SEQ_EXPAND_ELEMENT,(macro)(seq))

#define BOOST_TYPEOF_SEQ_ENUM_TRAILING(seq,macro)\

    BOOST_PP_ENUM_TRAILING(BOOST_PP_SEQ_SIZE(seq),BOOST_TYPEOF_SEQ_EXPAND_ELEMENT,(macro)(seq))

#define BOOST_TYPEOF_SEQ_EXPAND_ELEMENT_1(z,n,seq)\

    BOOST_PP_SEQ_ELEM(0,seq) (z,n,BOOST_PP_SEQ_ELEM(n,BOOST_PP_SEQ_ELEM(1,seq)))

#define BOOST_TYPEOF_SEQ_ENUM_1(seq,macro)\

    BOOST_PP_ENUM(BOOST_PP_SEQ_SIZE(seq),BOOST_TYPEOF_SEQ_EXPAND_ELEMENT_1,(macro)(seq))

#define BOOST_TYPEOF_SEQ_ENUM_TRAILING_1(seq,macro)\

    BOOST_PP_ENUM_TRAILING(BOOST_PP_SEQ_SIZE(seq),BOOST_TYPEOF_SEQ_EXPAND_ELEMENT_1,(macro)(seq))

//

#define BOOST_TYPEOF_PLACEHOLDER(z, n, elem)\

    BOOST_TYPEOF_VIRTUAL(PLACEHOLDER, elem)(elem)

#define BOOST_TYPEOF_PLACEHOLDER_TYPES(z, n, elem)\

    BOOST_TYPEOF_VIRTUAL(PLACEHOLDER_TYPES, elem)(elem, n)

#define BOOST_TYPEOF_REGISTER_TEMPLATE_ENCODE_PARAM(r, data, n, elem)\

    BOOST_TYPEOF_VIRTUAL(ENCODE, elem)(elem, n)

#define BOOST_TYPEOF_REGISTER_TEMPLATE_DECODE_PARAM(r, data, n, elem)\

    BOOST_TYPEOF_VIRTUAL(DECODE, elem)(elem, n)

#define BOOST_TYPEOF_REGISTER_TEMPLATE_PARAM_PAIR(z, n, elem) \

    BOOST_TYPEOF_VIRTUAL(EXPANDTYPE, elem)(elem) BOOST_PP_CAT(P, n)

#define BOOST_TYPEOF_REGISTER_DEFAULT_TEMPLATE_TYPE(Name,Params,ID)\

    Name< BOOST_PP_ENUM_PARAMS(BOOST_PP_SEQ_SIZE(Params), P) >

//Since we are creating an internal decode struct, we need to use different template names, T instead of P.

#define BOOST_TYPEOF_REGISTER_DECODER_TYPE_PARAM_PAIR(z,n,elem) \

    BOOST_TYPEOF_VIRTUAL(EXPANDTYPE, elem)(elem) BOOST_PP_CAT(T, n)

//Default template param decoding

#define BOOST_TYPEOF_TYPEDEF_DECODED_TEMPLATE_TYPE(Name,Params)\

    typedef Name<BOOST_PP_ENUM_PARAMS(BOOST_PP_SEQ_SIZE(Params),P)> type;        

//Branch the decoding

#define BOOST_TYPEOF_TYPEDEF_DECODED_TYPE(Name,Params)\

    BOOST_PP_IF(BOOST_TYPEOF_HAS_TEMPLATES(Params),\

        BOOST_TYPEOF_TYPEDEF_DECODED_TEMPLATE_TEMPLATE_TYPE,\

        BOOST_TYPEOF_TYPEDEF_DECODED_TEMPLATE_TYPE)(Name,Params)

#define BOOST_TYPEOF_REGISTER_TEMPLATE_IMPL(Name, Params, Size, ID)\

    BOOST_TYPEOF_BEGIN_ENCODE_NS\

    BOOST_TYPEOF_REGISTER_TEMPLATE_TEMPLATE_IMPL(Name, Params, ID)\

    template<class V\

        BOOST_TYPEOF_SEQ_ENUM_TRAILING(Params, BOOST_TYPEOF_REGISTER_TEMPLATE_PARAM_PAIR)\

    >\

    struct encode_type_impl<V, Name<BOOST_PP_ENUM_PARAMS(Size, P)> >\

    {\

        typedef typename boost::type_of::push_back<V, boost::mpl::size_t<ID> >::type V0;\

        BOOST_PP_SEQ_FOR_EACH_I(BOOST_TYPEOF_REGISTER_TEMPLATE_ENCODE_PARAM, ~, Params)\

        typedef BOOST_PP_CAT(V, Size) type;\

    };\

    template<class Iter>\

    struct decode_type_impl<boost::mpl::size_t<ID>, Iter>\

    {\

        typedef Iter iter0;\

        BOOST_PP_SEQ_FOR_EACH_I(BOOST_TYPEOF_REGISTER_TEMPLATE_DECODE_PARAM, ~, Params)\

        BOOST_TYPEOF_TYPEDEF_DECODED_TYPE(Name, Params)\

        typedef BOOST_PP_CAT(iter, Size) iter;\

    };\

    BOOST_TYPEOF_END_ENCODE_NS

#endif//BOOST_TYPEOF_TEMPLATE_ENCODING_HPP_INCLUDED