// file      : Utility/ReferenceCounting/SmartPtr.hpp
// author    : Boris Kolpackov <boris@kolpackov.net>
// copyright : Copyright (c) 2002-2003 Boris Kolpackov
// license   : http://kolpackov.net/license.html

namespace Utility
{
  namespace ReferenceCounting
  {
    template <typename T>
    class SmartPtr
    {
    public:
      typedef
      T
      Type;

      class NotInitialized_ {};
      typedef
      ExH::Compound<NotInitialized_, ExH::Logic::DescriptiveException>
      NotInitialized;

    public:
      // c-tor's

      SmartPtr () throw ();
      SmartPtr (Type* ptr) throw ();
      SmartPtr (SmartPtr<Type> const& s_ptr)
        throw (Interface::Exception, Interface::SystemException);

      template <typename Other>
      SmartPtr (SmartPtr<Other> const& s_ptr)
        throw (Interface::Exception, Interface::SystemException);

      // d-tor

      ~SmartPtr () throw ();

      // assignment & copy-assignment operators

      SmartPtr<Type>&
      operator= (Type* ptr) throw ();

      SmartPtr<Type>&
      operator= (SmartPtr<Type> const& s_ptr)
        throw (Interface::Exception, Interface::SystemException);

      template <typename Other>
      SmartPtr<Type>&
      operator= (SmartPtr<Other> const& s_ptr)
        throw (Interface::Exception, Interface::SystemException);

      //conversions

      operator Type* () const throw ();

      // accessors

      Type*
      operator-> () const throw (NotInitialized);

      Type*
      in () const throw ();

      Type*
      retn() throw ();

    private:
      Type* ptr_;
    };

    // Specialization of add_ref function for SmartPtr<T>
    template <typename T>
    T*
    add_ref (SmartPtr<T> const& ptr)
      throw (Interface::Exception, Interface::SystemException);


    // Dynamic type conversion function for SmartPtr's
    template <typename D, typename S>
    D*
    smart_cast (SmartPtr<S> const& s)
      throw (Interface::Exception, Interface::SystemException);

    // Acquisition function
    template <typename T>
    SmartPtr<T>
    acquire (T* ptr) throw (Interface::Exception, Interface::SystemException);
  }
}