#pragma once

#if !defined(MIJIN_INTERNAL_HELPERS_HPP_INCLUDED)
#define MIJIN_INTERNAL_HELPERS_HPP_INCLUDED 1

#include <type_traits>
#include "../util/traits.hpp"

#define MIJIN_IDENTITY(what) what
#define MIJIN_NULLIFY(what)

#define MIJIN_SMART_QUOTE(chr_type, text)                                      \
[]<typename TChar__>(TChar__) consteval                                        \
{                                                                              \
    if constexpr (std::is_same_v<TChar__, char>)                               \
    {                                                                          \
        return text;                                                           \
    }                                                                          \
    else if constexpr (std::is_same_v<TChar__, wchar_t>)                       \
    {                                                                          \
        return L ## text;                                                      \
    }                                                                          \
    else if constexpr (std::is_same_v<TChar__, char8_t>)                       \
    {                                                                          \
        return u8 ## text;                                                     \
    }                                                                          \
    else                                                                       \
    {                                                                          \
        static_assert(::mijin::always_false_v<TChar__>, "Invalid char type."); \
    }                                                                          \
}(chr_type())

#define MIJIN_SMART_STRINGIFY(chr_type, text) MIJIN_SMART_QUOTE(chr_type, #text)

#define MIJIN_DEFINE_CHAR_VERSIONS_IMPL(type_name, prefix_a, prefix_b, prefix_c, set_args) \
prefix_a prefix_b(char) prefix_c                                                           \
using C ## type_name = Base ## type_name <set_args(char)>;                                 \
                                                                                           \
prefix_a prefix_b(wchar_t) prefix_c                                                        \
using W ## type_name = Base ## type_name <set_args(wchar_t)>;                              \
                                                                                           \
prefix_a prefix_b(char8_t) prefix_c                                                        \
using U ## type_name = Base ## type_name <set_args(char8_t)>;                              \
                                                                                           \
using type_name = Base ## type_name<>;

#define MIJIN_DEFINE_CHAR_VERSIONS_TMPL(type_name, remaining_args, set_args) \
MIJIN_DEFINE_CHAR_VERSIONS_IMPL(type_name, template<, remaining_args, >, set_args)

#define MIJIN_DEFINE_CHAR_VERSIONS_CUSTOM(type_name, set_args)   \
MIJIN_DEFINE_CHAR_VERSIONS_IMPL(type_name, , MIJIN_NULLIFY, , set_args)

#define MIJIN_DEFINE_CHAR_VERSIONS(type_name) \
MIJIN_DEFINE_CHAR_VERSIONS_CUSTOM(type_name, MIJIN_IDENTITY)

#endif // !defined(MIJIN_INTERNAL_HELPERS_HPP_INCLUDED)