// The MIT License (MIT)

// Copyright (c) 2013 Danny Y., Rapptz

// Permission is hereby granted, free of charge, to any person obtaining a copy of
// this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

#ifndef SOL_RESOLVE_HPP
#define SOL_RESOLVE_HPP

#include "traits.hpp"
#include "tuple.hpp"

namespace sol {
namespace detail {
template<class R, class... Args, class F, class = typename std::result_of<Unqualified<F>( Args... )>::type>
auto resolve_i( types<R( Args... )>, F&& )->R( Unqualified<F>::* )( Args... ) {
    typedef R( Sig )( Args... );
    typedef Unqualified<F> Fu;
    return static_cast<Sig Fu::*>( &Fu::operator() );
}

template<class F>
auto resolve_f( std::true_type, F&& f ) -> decltype( resolve_i( types<function_signature_t<decltype( &Unqualified<F>::operator() )>>( ), std::forward<F>( f ) ) ) {
    typedef Unqualified<F> Fu;
    return resolve_i( types<function_signature_t<decltype( &Fu::operator() )>>( ), std::forward<F>( f ) );
}

template<class F>
void resolve_f( std::false_type, F&& f ) {
    static_assert( has_deducible_signature<F>::value, "Cannot use no-template-parameter call with an overloaded functor: specify the signature" );
}

template<class F>
auto resolve_i( types<>, F&& f ) -> decltype( resolve_f( has_deducible_signature<Unqualified<F>> {}, std::forward<F>( f ) ) ) {
    return resolve_f( has_deducible_signature<Unqualified<F>> {}, std::forward<F>( f ) );
}

template<class... Args, class F, class R = typename std::result_of<F&( Args... )>::type>
auto resolve_i( types<Args...>, F&& f ) -> decltype( resolve_i( types<R( Args... )>( ), std::forward<F>( f ) ) ) {
    return resolve_i( types<R( Args... )>( ), std::forward<F>( f ) );
}

template<class Sig, class C>
Sig C::* resolve_v( std::false_type, Sig C::* mem_func_ptr ) {
    return mem_func_ptr;
}

template<class Sig, class C>
Sig C::* resolve_v( std::true_type, Sig C::* mem_variable_ptr ) {
    return mem_variable_ptr;
}
} // detail

template<class... Args, class R>
auto resolve( R fun_ptr( Args... ) ) -> R( *)( Args... ) {
    return fun_ptr;
}

template<class Sig>
Sig* resolve( Sig* fun_ptr ) {
    return fun_ptr;
}

template<class... Args, class R, class C>
auto resolve( R( C::*mem_ptr )( Args... ) ) -> R( C::* )( Args... ) {
    return mem_ptr;
}

template<class Sig, class C>
Sig C::* resolve( Sig C::* mem_ptr ) {
    return detail::resolve_v( std::is_member_object_pointer<Sig C::*>( ), mem_ptr );
}

template<class... Sig, class F>
auto resolve( F&& f ) ->  decltype( detail::resolve_i( types<Sig...>( ), std::forward<F>( f ) ) ) {
    return detail::resolve_i( types<Sig...>( ), std::forward<F>( f ) );
}
} // sol

#endif // SOL_RESOLVE_HPP