//
//  const_propogating_ptr.hpp
//  pointers
//
//  Created by Sam Jaffe on 12/3/16.
//

#pragma once
#include <memory>

#include "pointer_fwd.hpp"
#include "ptr_compare.hpp"

template <typename P>
class const_propogating_ptr {
public:
  using element_type = typename std::pointer_traits<P>::element_type;
  using pointer = element_type  *;
  using reference = element_type &;
  using const_pointer = element_type const *;
  using const_reference = element_type const &;

  const_propogating_ptr() noexcept : _ptr(nullptr) {}
  const_propogating_ptr(P const & p) noexcept(std::is_nothrow_copy_constructible<P>::value) : _ptr(p) {}
  const_propogating_ptr(P && p) noexcept(std::is_nothrow_move_constructible<P>::value) : _ptr(std::move(p)) {}
  
  const_propogating_ptr(const_propogating_ptr &) noexcept(std::is_nothrow_copy_constructible<P>::value) = default;
  const_propogating_ptr(const_propogating_ptr &&) noexcept(std::is_nothrow_move_constructible<P>::value) = default;
  const_propogating_ptr(const_propogating_ptr const &) = delete;
  const_propogating_ptr& operator=(const_propogating_ptr &) noexcept(std::is_nothrow_copy_constructible<P>::value) = default;
  const_propogating_ptr& operator=(const_propogating_ptr &&) noexcept(std::is_nothrow_move_constructible<P>::value) = default;
  const_propogating_ptr& operator=(const_propogating_ptr const &) = delete;
  
  template <typename Y>
  explicit operator const_propogating_ptr<Y>() & noexcept(std::is_nothrow_copy_constructible<Y>::value) {
    return _ptr;
  }
  
  template <typename Y>
  explicit operator const_ptr<Y>() const noexcept(std::is_nothrow_copy_constructible<Y>::value) {
    return _ptr;
  }
  
  template <typename Y>
  explicit operator const_propogating_ptr<Y>() const & = delete;
  
  operator bool() const noexcept {
    return static_cast<bool>(_ptr);
  }
  
  reference operator*() noexcept { return *_ptr; }
  pointer get() noexcept { return std::addressof(operator*()); }
  pointer operator->() noexcept { return get(); }
  
  const_reference operator*() const noexcept { return *_ptr; }
  const_pointer get() const noexcept { return std::addressof(operator*()); }
  const_pointer operator->() const noexcept { return get(); }
  
private:
  P _ptr;
};

POINTER_TEMPLATE_COMPARE( const_propogating_ptr )