// This file is distributed under the BSD License.
// See "license.txt" for details.
// Copyright 2009-2012, Jonathan Turner (jonathan@emptycrate.com)
// Copyright 2009-2015, Jason Turner (jason@emptycrate.com)
// http://www.chaiscript.com

#ifndef CHAISCRIPT_CALLABLE_TRAITS_HPP_
#define CHAISCRIPT_CALLABLE_TRAITS_HPP_

#include <memory>

namespace chaiscript {
  namespace dispatch {
    namespace detail {
      template<typename Class, typename ... Param>
      struct Constructor
      {
        template<typename ... Inner>
        std::shared_ptr<Class> operator()(Inner&& ... inner) const {
          return std::make_shared<Class>(std::forward<Inner>(inner)...);
        }
      };

      template<typename Ret, typename Class, typename ... Param>
      struct Const_Caller
      {
        Const_Caller(Ret (Class::*t_func)(Param...) const) : m_func(t_func) {}

        template<typename ... Inner>
        Ret operator()(const Class &o, Inner&& ... inner) const {
          return (o.*m_func)(std::forward<Inner>(inner)...);
        }

        Ret (Class::*m_func)(Param...) const;
      };

      template<typename Ret, typename Class, typename ... Param>
      struct Caller
      {
        Caller(Ret (Class::*t_func)(Param...)) : m_func(t_func) {}

        template<typename ... Inner>
        Ret operator()(Class &o, Inner&& ... inner) const {
          return (o.*m_func)(std::forward<Inner>(inner)...);
        }

        Ret (Class::*m_func)(Param...);
      };

      template<typename T>
        struct Function_Signature
        {

          template<typename Ret, typename ... Param>
            static Ret deduce_ret_type(Function_Signature<Ret (Param...)> *);

          typedef T Signature;
          typedef Function_Signature<T> *ptr_type;
          typedef decltype(deduce_ret_type(ptr_type(nullptr))) Return_Type;

        };

      template<typename T>
        struct Callable_Traits
        {

          template<typename Ret, typename ... Param>
            static Function_Signature<Ret (Param...)> deduce_sig_type(Ret (T::*)(Param...) const);

          typedef typename decltype(deduce_sig_type(&T::operator()))::Signature Signature;
          typedef decltype(deduce_sig_type(&T::operator())) Signature_Object;
          typedef typename Signature_Object::Return_Type Return_Type;
        };
    }
  }
}

#endif