#ifndef Rice__TypeRegistry__hpp_
#define Rice__TypeRegistry__hpp_

#include <optional>
#include <string>
#include <typeindex>
#include <typeinfo>
#include <unordered_map>

#include "ruby.hpp"

/* The type registry keeps track of all C++ types wrapped by Rice. When a native function returns 
   an instance of a class/struct we look up its type to verity that it has been registered. 
   
   We have to do this to support C++ inheritance. If a C++ function returns a pointer/reference
   to an Abstract class, the actual returned object will be a Child class. However, all we know
   from the C++ method signature is that it is an Absract class - thus the need for a registry.*/

namespace Rice::detail
{
  class TypeRegistry
  {
  public:
    template <typename T>
    void add(VALUE klass, rb_data_type_t* rbType);

    template <typename T>
    void remove();

    template <typename T>
    bool isDefined();

    template <typename T>
    bool verifyDefined();
      
    template <typename T>
    std::pair<VALUE, rb_data_type_t*> figureType(const T& object);

  private:
    std::optional<std::pair<VALUE, rb_data_type_t*>> lookup(const std::type_info& typeInfo);
    std::unordered_map<std::type_index, std::pair<VALUE, rb_data_type_t*>> registry_{};
  };
}

#include "TypeRegistry.ipp"

#endif // Rice__TypeRegistry__hpp_