draconisplusplus/include/rfl/bson/Parser.hpp

#ifndef RFL_BSON_PARSER_HPP_
#define RFL_BSON_PARSER_HPP_

#include <bson/bson.h>

#include "../parsing/Parser.hpp"
#include "Reader.hpp"
#include "Writer.hpp"

namespace rfl::parsing {

  /// bson_oid_t needs to be treated as a special case, otherwise it will be
  /// read as a struct.
  template <class R, class W, class ProcessorsType>
    requires AreReaderAndWriter<R, W, bson_oid_t>
  struct Parser<R, W, ProcessorsType, bson_oid_t> {
    using InputVarType  = typename R::InputVarType;
    using OutputVarType = typename W::OutputVarType;

    using ParentType = Parent<W>;

    static Result<bson_oid_t> read(const R& _r,
                                   const InputVarType& _var) noexcept {
      return _r.template to_basic_type<bson_oid_t>(_var);
    }

    template <class P>
    static void write(const W& _w,
                      const bson_oid_t& _oid,
                      const P& _parent) noexcept {
      ParentType::add_value(_w, _oid, _parent);
    }

    static schema::Type to_schema(
        std::map<std::string, schema::Type>* _definitions) {
      static_assert(rfl::always_false_v<R>,
                    "bson_oid_t cannot be expressed inside a JSON schema.");
      return schema::Type {schema::Type::String {}};
    }
  };

} // namespace rfl::parsing

namespace rfl::bson {

  template <class T, class ProcessorsType>
  using Parser = parsing::Parser<Reader, Writer, T, ProcessorsType>;

} // namespace rfl::bson

#endif