//
// Created by selim on 06.11.22.
//

#ifndef AUTOCAT_GNOME_JSONOPTIONAL_H
#define AUTOCAT_GNOME_JSONOPTIONAL_H

#include <nlohmann/json.hpp>
#include <iostream>

namespace nlohmann {

    template<class J, class T>
    void optional_to_json(J& j, const char* name, const std::optional<T>& value)
    {
        if (value)
        {
            j[name] = *value;
        }
    }

    template<class J, class T>
    void optional_from_json(const J& j, const char* name, std::optional<T>& value)
    {
        const auto it = j.find(name);
        if (it != j.end())
        {
            if(j.at(name).is_null()) {
                value = std::nullopt;
            } else {
                value = it->template get<T>();
            }
        }
        else
        {
            value = std::nullopt;
        }
    }

    template <typename>
    constexpr bool is_optional = false;
    template <typename T>
    constexpr bool is_optional<std::optional<T>> = true;

    template <typename T>
    void extended_to_json(const char *key, nlohmann::json &j, const T &value) {
        if constexpr (is_optional<T>)
            optional_to_json(j, key, value);
        else
            j[key] = value;
    }
    template <typename T>
    void extended_from_json(const char *key, const nlohmann::json &j, T &value) {
        //std::cout << "parsing key " << key << std::endl;
        if constexpr (is_optional<T>) {
            optional_from_json(j, key, value);
        } else {
            j.at(key).get_to(value);
        }
    }

    #define EXTEND_JSON_TO(v1) extended_to_json(#v1, nlohmann_json_j, nlohmann_json_t.v1);
    #define EXTEND_JSON_FROM(v1) extended_from_json(#v1, nlohmann_json_j, nlohmann_json_t.v1);

    #define NLOHMANN_JSONIFY_ALL_THINGS(Type, ...)                                          \
      friend void to_json(nlohmann::json &nlohmann_json_j, const Type &nlohmann_json_t) {   \
          NLOHMANN_JSON_EXPAND(NLOHMANN_JSON_PASTE(EXTEND_JSON_TO, __VA_ARGS__))            \
      }                                                                                     \
      friend void from_json(const nlohmann::json &nlohmann_json_j, Type &nlohmann_json_t) { \
          NLOHMANN_JSON_EXPAND(NLOHMANN_JSON_PASTE(EXTEND_JSON_FROM, __VA_ARGS__))          \
      }

}

#endif //AUTOCAT_GNOME_JSONOPTIONAL_H