graph_psite_base.hh

// Copyright (C) 2008, 2009 EPITA Research and Development Laboratory (LRDE)
//
// This file is part of Olena.
//
// Olena is free software: you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation, version 2 of the License.
//
// Olena is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Olena.  If not, see <http://www.gnu.org/licenses/>.
//
// As a special exception, you may use this file as part of a free
// software project without restriction.  Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to produce
// an executable, this file does not by itself cause the resulting
// executable to be covered by the GNU General Public License.  This
// exception does not however invalidate any other reasons why the
// executable file might be covered by the GNU General Public License.

#ifndef MLN_CORE_INTERNAL_GRAPH_PSITE_BASE_HH
# define MLN_CORE_INTERNAL_GRAPH_PSITE_BASE_HH


# include <mln/core/internal/pseudo_site_base.hh>



namespace mln
{

  namespace internal
  {

    template <typename S, typename E>
    class graph_psite_base : public internal::pseudo_site_base_< const mln_site(S)&,
                                                                 E >
    {
    public:

      // This associated type is important to know that this particular
      // pseudo site knows the site set it refers to.
      typedef S target;

      // As a Proxy:
      const mln_site(S)& subj_();

      typedef typename S::graph_element::id_t id_t;

      void change_target(const S& new_target);
      void update_id(unsigned elt_id);

      const S* target_() const; // Hook to the target.

      const S& site_set() const;

      const typename S::graph_t& graph() const;

      id_t id() const;


      bool is_valid() const;
      void invalidate();

      operator unsigned () const;

      operator typename S::graph_element::id_t () const;

      operator const typename S::graph_element&() const;

      const typename S::graph_element& element() const;

      const typename S::graph_element& p_hook_() const;

    protected:


      graph_psite_base();
      graph_psite_base(const S& s);
      graph_psite_base(const S& , unsigned id);

      const S* s_;
      mln_site(S) site_;
      typename S::graph_element elt_;
    };


  /* FIXME: Shouldn't those comparisons be part of a much general
     mechanism?  */

  template <typename S, typename E>
  bool
  operator==(const graph_psite_base<S,E>& lhs, const graph_psite_base<S,E>& rhs);

  template <typename S, typename E>
  bool
  operator!=(const graph_psite_base<S,E>& lhs, const graph_psite_base<S,E>& rhs);

  template <typename S, typename E>
  bool
  operator< (const graph_psite_base<S,E>& lhs, const graph_psite_base<S,E>& rhs);


  template <typename S, typename P, typename E>
  struct subject_impl< const graph_psite_base<S,P>&, E >
  {
    const S* target_() const;
    const S& site_set() const;
    const typename S::graph_t& graph() const;
    unsigned id() const;
    bool is_valid() const;
//    operator unsigned() const;
//    operator const typename S::graph_element&() const;
    const typename S::graph_element& element() const;
    const typename S::graph_element& p_hook_() const;

    private:
    const E& exact_() const;
  };

  template <typename S, typename P, typename E>
  struct subject_impl<       graph_psite_base<S,P>&, E > :
  subject_impl< const graph_psite_base<S,P>&, E >
  {
    void change_target(const S& new_target);
    void update_id(unsigned elt_id);
    void invalidate();

    private:
    E& exact_();
  };



# ifndef MLN_INCLUDE_ONLY


  template <typename S, typename E>
  inline
  graph_psite_base<S,E>::graph_psite_base()
    : s_(0)
  {
  }

  template <typename S, typename E>
  inline
  graph_psite_base<S,E>::graph_psite_base(const S& s)
  {
    change_target(s);
  }

  template <typename S, typename E>
  inline
  graph_psite_base<S,E>::graph_psite_base(const S& s, unsigned id)
  {
    change_target(s);
    update_id(id);
  }

  template <typename S, typename E>
  inline
  void
  graph_psite_base<S,E>::change_target(const S& new_target)
  {
    s_ = & new_target;
    elt_.change_graph(new_target.graph());
  }

  template <typename S, typename E>
  inline
  void
  graph_psite_base<S,E>::update_id(unsigned id)
  {
    mln_precondition(s_ != 0);
    elt_.update_id(id);
    site_ = s_->function()(elt_.id());
  }

  template <typename S, typename E>
  inline
  const S*
  graph_psite_base<S,E>::target_() const
  {
    return s_;
  }

  template <typename S, typename E>
  inline
  const S&
  graph_psite_base<S,E>::site_set() const
  {
    mln_precondition(s_ != 0);
    return *s_;
  }

  template <typename S, typename E>
  inline
  const typename S::graph_t&
  graph_psite_base<S,E>::graph() const
  {
    mln_precondition(s_ != 0);
    return s_->graph();
  }

  template <typename S, typename E>
  inline
  typename graph_psite_base<S,E>::id_t
  graph_psite_base<S,E>::id() const
  {
    return elt_.id();
  }

  template <typename S, typename E>
  inline
  bool
  graph_psite_base<S,E>::is_valid() const
  {
    return s_ != 0 && s_->is_valid() && elt_.is_valid();
  }

  template <typename S, typename E>
  inline
  void
  graph_psite_base<S,E>::invalidate()
  {
    s_ = 0;
    elt_.invalidate();
  }

  template <typename S, typename E>
  inline
  const mln_site(S)&
  graph_psite_base<S,E>::subj_()
  {
    /*FIXME: we may like to enable the following precondition, however, we
    ** can't do that since neighb_*_niters update the psite target after having
    ** taken the adress of the subject.
    */
    // mln_precondition(is_valid());
    return site_;
  }

  template <typename S, typename E>
  inline
  graph_psite_base<S,E>::operator unsigned () const
  {
    mln_precondition(is_valid());
    return elt_.id();
  }

  template <typename S, typename E>
  inline
  graph_psite_base<S,E>::operator typename S::graph_element::id_t () const
  {
    mln_precondition(is_valid());
    return elt_.id();
  }

  template <typename S, typename E>
  inline
  graph_psite_base<S,E>::operator const typename S::graph_element&() const
  {
    //mln_precondition(is_valid());
    return elt_;
  }

  template <typename S, typename E>
  inline
  const typename S::graph_element&
  graph_psite_base<S,E>::element() const
  {
    /*FIXME: we may like to enable the following precondition, however, we
    ** can't do that since neighb_*_niters update the psite target after having
    ** taken the adress of the subject.
    */
    // mln_precondition(is_valid());
    return elt_;
  }

  template <typename S, typename E>
  inline
  const typename S::graph_element&
  graph_psite_base<S,E>::p_hook_() const
  {
    return elt_;
  }


  template <typename S, typename P, typename E>
  inline
  const E&
  subject_impl< const graph_psite_base<S,P>&, E >::exact_() const
  {
    return internal::force_exact<const E>(*this);
  }

  template <typename S, typename P, typename E>
  inline
  const S*
  subject_impl< const graph_psite_base<S,P>&, E >::target_() const
  {
    return exact_().get_subject().target();
  }

  template <typename S, typename P, typename E>
  inline
  const S&
  subject_impl< const graph_psite_base<S,P>&, E >::site_set() const
  {
    return exact_().get_subject().site_set();
  }


  template <typename S, typename P, typename E>
  inline
  const typename S::graph_t&
  subject_impl< const graph_psite_base<S,P>&, E >::graph() const
  {
    return exact_().get_subject().graph();
  }

  template <typename S, typename P, typename E>
  inline
  unsigned
  subject_impl< const graph_psite_base<S,P>&, E >::id() const
  {
    return exact_().get_subject().id();
  };

  template <typename S, typename P, typename E>
  inline
  bool
  subject_impl< const graph_psite_base<S,P>&, E >::is_valid() const
  {
    return exact_().get_subject().is_valid();
  }

  template <typename S, typename P, typename E>
  inline
  const typename S::graph_element&
  subject_impl< const graph_psite_base<S,P>&, E >::element() const
  {
    return exact_().get_subject().element();
  }

  template <typename S, typename P, typename E>
  inline
  const typename S::graph_element&
  subject_impl< const graph_psite_base<S,P>&, E >::p_hook_() const
  {
    return exact_().get_subject().p_hook_();
  }


  template <typename S, typename P, typename E>
  inline
  E&
  subject_impl< graph_psite_base<S,P>&, E >::exact_()
  {
    return internal::force_exact<E>(*this);
  }

  template <typename S, typename P, typename E>
  inline
  void
  subject_impl<       graph_psite_base<S,P>&, E >::change_target(const S& new_target)
  {
    exact_().get_subject().change_target(new_target);
  }

  template <typename S, typename P, typename E>
  inline
  void
  subject_impl<       graph_psite_base<S,P>&, E >::update_id(unsigned id)
  {
    exact_().get_subject().update_id(id);
  };

  template <typename S, typename P, typename E>
  inline
  void
  subject_impl< graph_psite_base<S,P>&, E >::invalidate()
  {
    exact_().get_subject().invalidate();
  }

# endif // ! MLN_INCLUDE_ONLY

} // end of namespace internal

  } // end of namespace mln


#endif // ! MLN_CORE_INTERNAL_GRAPH_PSITE_BASE_HH