#ifndef BOOST_LEAF_DETAIL_PRINT_HPP_INCLUDED
#define BOOST_LEAF_DETAIL_PRINT_HPP_INCLUDED

// Copyright (c) 2018-2020 Emil Dotchevski and Reverge Studios, Inc.

// 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_LEAF_ENABLE_WARNINGS
#   if defined(__clang__)
#       pragma clang system_header
#   elif (__GNUC__*100+__GNUC_MINOR__>301)
#       pragma GCC system_header
#   elif defined(_MSC_VER)
#       pragma warning(push,1)
#   endif
#endif

#include <boost/leaf/detail/optional.hpp>
#include <iosfwd>
#include <cstring>

namespace boost { namespace leaf {

    namespace leaf_detail
    {
        template <int N>
        BOOST_LEAF_CONSTEXPR inline char const * check_prefix( char const * t, char const (&prefix)[N] )
        {
            return std::strncmp(t,prefix,sizeof(prefix)-1)==0 ? t+sizeof(prefix)-1 : t;
        }
    }

    template <class Name>
    inline char const * type()
    {
        using leaf_detail::check_prefix;
    char const * t =
#ifdef __FUNCSIG__
        __FUNCSIG__;
#else
        __PRETTY_FUNCTION__;
#endif
#if defined(__clang__)
        BOOST_LEAF_ASSERT(check_prefix(t,"const char *boost::leaf::type() ")==t+32);
        return t+32;
#elif defined(__GNUC__)
        BOOST_LEAF_ASSERT(check_prefix(t,"const char* boost::leaf::type() ")==t+32);
        return t+32;
#else
        char const * clang_style = check_prefix(t,"const char *boost::leaf::type() ");
        if( clang_style!=t )
            return clang_style;
        char const * gcc_style = check_prefix(t,"const char* boost::leaf::type() ");
        if( gcc_style!=t )
            return gcc_style;
#endif
        return t;
    }

    namespace leaf_detail
    {
        template <class T, class E = void>
        struct is_printable: std::false_type
        {
        };

        template <class T>
        struct is_printable<T, decltype(std::declval<std::ostream&>()<<std::declval<T const &>(), void())>: std::true_type
        {
        };

        ////////////////////////////////////////

        template <class T, class E = void>
        struct has_printable_member_value: std::false_type
        {
        };

        template <class T>
        struct has_printable_member_value<T, decltype(std::declval<std::ostream&>()<<std::declval<T const &>().value, void())>: std::true_type
        {
        };

        ////////////////////////////////////////

        template <class Wrapper, bool WrapperPrintable=is_printable<Wrapper>::value, bool ValuePrintable=has_printable_member_value<Wrapper>::value>
        struct diagnostic;

        template <class Wrapper, bool ValuePrintable>
        struct diagnostic<Wrapper, true, ValuePrintable>
        {
            static constexpr bool is_invisible = false;
            static void print( std::ostream & os, Wrapper const & x )
            {
                os << x;
            }
        };

        template <class Wrapper>
        struct diagnostic<Wrapper, false, true>
        {
            static constexpr bool is_invisible = false;
            static void print( std::ostream & os, Wrapper const & x )
            {
                os << type<Wrapper>() << ": " << x.value;
            }
        };

        template <class Wrapper>
        struct diagnostic<Wrapper, false, false>
        {
            static constexpr bool is_invisible = false;
            static void print( std::ostream & os, Wrapper const & )
            {
                os << type<Wrapper>() << ": {Non-Printable}";
            }
        };

#ifndef BOOST_LEAF_NO_EXCEPTIONS
        template <>
        struct diagnostic<std::exception_ptr, false, false>
        {
            static constexpr bool is_invisible = true;
            BOOST_LEAF_CONSTEXPR static void print( std::ostream &, std::exception_ptr const & )
            {
            }
        };
#endif
    }

} }

#endif
