draconisplusplus/include/rfl/parsing/Parser_shared_ptr.hpp

#ifndef RFL_PARSING_PARSER_SHARED_PTR_HPP_
#define RFL_PARSING_PARSER_SHARED_PTR_HPP_

#include <map>
#include <memory>
#include <type_traits>

#include "../Ref.hpp"
#include "../Result.hpp"
#include "../always_false.hpp"
#include "Parent.hpp"
#include "Parser_base.hpp"
#include "schema/Type.hpp"

namespace rfl::parsing {

  template <class R, class W, class T, class ProcessorsType>
    requires AreReaderAndWriter<R, W, std::shared_ptr<T>>
  struct Parser<R, W, std::shared_ptr<T>, ProcessorsType> {
    using InputVarType  = typename R::InputVarType;
    using OutputVarType = typename W::OutputVarType;

    using ParentType = Parent<W>;

    static Result<std::shared_ptr<T>>
    read(const R& _r, const InputVarType& _var) noexcept {
      if (_r.is_empty(_var)) {
        return std::shared_ptr<T>();
      }
      const auto to_ptr = [](auto&& _t) {
        return std::make_shared<T>(std::move(_t));
      };
      return Parser<R, W, std::remove_cvref_t<T>, ProcessorsType>::read(
                 _r, _var
      )
          .transform(to_ptr);
    }

    template <class P>
    static void write(
        const W&                  _w,
        const std::shared_ptr<T>& _s,
        const P&                  _parent
    ) noexcept {
      if (!_s) {
        ParentType::add_null(_w, _parent);
        return;
      }
      Parser<R, W, std::remove_cvref_t<T>, ProcessorsType>::write(
          _w, *_s, _parent
      );
    }

    static schema::Type to_schema(
        std::map<std::string, schema::Type>* _definitions
    ) {
      using U = std::remove_cvref_t<T>;
      return schema::Type {schema::Type::Optional {Ref<schema::Type>::make(
          Parser<R, W, U, ProcessorsType>::to_schema(_definitions)
      )}};
    }
  };

} // namespace rfl::parsing

#endif