draconisplusplus/include/rfl/parsing/Parser_unique_ptr.hpp

#ifndef RFL_PARSING_PARSER_UNIQUE_PTR_HPP_
#define RFL_PARSING_PARSER_UNIQUE_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 {
  namespace parsing {

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

      using ParentType = Parent<W>;

      static Result<std::unique_ptr<T>>
      read(const R& _r, const InputVarType& _var) noexcept {
        if (_r.is_empty(_var)) {
          return std::unique_ptr<T>();
        }
        const auto to_ptr = [](auto&& _t) {
          return std::make_unique<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::unique_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 parsing
} // namespace rfl

#endif