#ifndef ALSK_ALSK_SKELETON_LINK_LINK_H
#define ALSK_ALSK_SKELETON_LINK_LINK_H

#include <tmp/pack.h>

#include "args.h"
#include "utility.h"

#include "../struct/struct.h"

namespace alsk {

/**
 * @brief hold the skeleton links
 */
template<template<typename...> class T, typename F, typename... Ts>
using L = S<T, F, Ts...>;

namespace impl {

/**
 * Pack of return types from links
 */
template<typename...> struct LinksToReturnTypes;

template<typename R, typename... Params, typename... Ls>
struct LinksToReturnTypes<R(Params...), Ls...> {
	using type = tmp::PackCat<tmp::Pack<R>, typename LinksToReturnTypes<Ls...>::type>;
};

template<template<typename...> class Skel, typename R, typename... Params, typename... InnerLs, typename... Ls>
struct LinksToReturnTypes<alsk::L<Skel, R(Params...), InnerLs...>, Ls...> {
	using type = tmp::PackCat<tmp::Pack<R>, typename LinksToReturnTypes<Ls...>::type>;
};

template<template<typename...> class Skel, std::size_t I, typename... Params, typename... InnerLs, typename... Ls>
struct LinksToReturnTypes<alsk::L<Skel, alsk::arg::R<I>(Params...), InnerLs...>, Ls...> {
	using rets = typename LinksToReturnTypes<InnerLs...>::type;
	using R = tmp::PackGet<rets, I>;
	using type = tmp::PackCat<tmp::Pack<R>, typename LinksToReturnTypes<Ls...>::type>;
};

template<>
struct LinksToReturnTypes<> {
	using type = tmp::Pack<>;
};

}

}

#endif