cpp-logger/include/logger/wrapper_object.h

//
//  wrapper_object.hpp
//  logging
//
//  Created by Sam Jaffe on 4/4/19.
//

#pragma once

#include <iostream>
#include <string>

#include "detail/to_string.h"
#include "detail/to_json.h"

namespace logging { namespace detail {
  class object {
  public:
    template <typename T> explicit object(T & object);
    
  private:
    friend std::ostream & operator<<(std::ostream & os, object const & obj) {
      return os << obj.to_string_(obj.ptr_);
    }
    template <typename> static std::string to_string_impl(void * ptr);
    template <typename> static json to_json_impl(void * ptr);

  private:
    void * ptr_;
    std::string (*to_string_)(void*);
    json (*to_json_)(void*);
  };
  
  
  template <typename T>
  std::string object::to_string_impl(void * ptr) {
    return to_string(*static_cast<T*>(ptr));
  }
  
  template <typename T>
  json object::to_json_impl(void * ptr) {
    return to_json(*static_cast<T*>(ptr));
  }
  
  template <typename T>
  object::object(T & object)
  : ptr_(&object),
  to_string_(&object::to_string_impl<T>),
  to_json_(&object::to_json_impl<T>) {
    
  }
} }