/**
	rjp++
	Copyright (C) 2020 rexy712

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program 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 General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef RJP_UTIL_HPP
#define RJP_UTIL_HPP

#include <rjp.h>
#include "integral.hpp"

namespace rjp{
	namespace detail{
		template<class To, class From, bool = std::is_same<std::remove_reference_t<To>,std::remove_reference_t<From>>::value>
		struct convert_helper;
		template<class To, class From>
		struct convert_helper<To,From,false>{
			static To perform(From&& t){
				return To(std::move(t));
			}
		};
		template<class To, class From>
		struct convert_helper<To,From&,false>{
			static To perform(const From& t){
				return To(const_cast<RJP_value*>(t.raw()), false);
			}
		};
		template<class To, class From>
		struct convert_helper<To,From,true>{
			static decltype(auto) perform(From&& t){
				return std::forward<From>(t);
			}
		};
	}

	template<class To, class From>
	To convert(From&& from){
		return detail::convert_helper<To,From>::perform(std::forward<From>(from));
	}

	namespace detail{
		template<class To, class From>
		struct get_ref{
			using type = std::remove_reference_t<To>;
		};
		template<class To, class From>
		struct get_ref<To, From&>{
			using type = std::remove_reference_t<To>&;
		};
		template<class To, class From>
		struct get_ref<To, From&&>{
			using type = std::remove_reference_t<To>&&;
		};
		template<class To, class From>
		struct get_ref<To&&, From&>{
			using type = To&&;
		};
		template<class To, class From>
		struct get_ref<To&&, From&&>{
			using type = To&&;
		};
	}

	template<class To, class From>
	decltype(auto) cast(From&& from){
		return static_cast<typename detail::get_ref<To,From&&>::type>(std::forward<From>(from));
	}

	namespace detail{
		template<class Val>
		void set_to_underlying(RJP_value* val, typename Val::underlying_type);
		template<>
		void set_to_underlying<rjp::integer>(RJP_value* val, RJP_int i);
		template<>
		void set_to_underlying<rjp::dfloat>(RJP_value* val, RJP_float f);
		template<>
		void set_to_underlying<rjp::boolean>(RJP_value* val, RJP_bool b);
	}
}

#endif