simple_state.hpp

support vector clustering for vc++

#ifndef BOOST_STATECHART_SIMPLE_STATE_HPP_INCLUDED
#define BOOST_STATECHART_SIMPLE_STATE_HPP_INCLUDED
//////////////////////////////////////////////////////////////////////////////
// Copyright 2002-2006 Andreas Huber Doenni
// Distributed under the Boost Software License, Version 1.0. (See accompany-
// ing file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//////////////////////////////////////////////////////////////////////////////



#include <boost/statechart/event.hpp>

#include <boost/statechart/detail/leaf_state.hpp>
#include <boost/statechart/detail/node_state.hpp>
#include <boost/statechart/detail/constructor.hpp>
#include <boost/statechart/detail/memory.hpp>

#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/identity.hpp>
#include <boost/mpl/is_sequence.hpp>
#include <boost/mpl/list.hpp>
#include <boost/mpl/empty.hpp>
#include <boost/mpl/size.hpp>
#include <boost/mpl/front.hpp>
#include <boost/mpl/at.hpp>
#include <boost/mpl/find.hpp>
#include <boost/mpl/find_if.hpp>
#include <boost/mpl/contains.hpp>
#include <boost/mpl/distance.hpp>
#include <boost/mpl/deref.hpp>
#include <boost/mpl/pop_front.hpp>
#include <boost/mpl/push_front.hpp>
#include <boost/mpl/clear.hpp>
#include <boost/mpl/placeholders.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/mpl/integral_c.hpp>
#include <boost/mpl/less.hpp>
#include <boost/mpl/equal_to.hpp>
#include <boost/mpl/not.hpp>
#include <boost/mpl/or.hpp>

#include <boost/mpl/plus.hpp>
#include <boost/mpl/max_element.hpp>
#include <boost/mpl/greater.hpp>

#include <boost/get_pointer.hpp>
#include <boost/intrusive_ptr.hpp>
#include <boost/assert.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/static_assert.hpp>
#include <boost/cast.hpp> // boost::polymorphic_downcast

#include <cstddef> // std::size_t



namespace boost
{
namespace statechart
{
namespace detail
{



//////////////////////////////////////////////////////////////////////////////
template< class T >
struct make_list : public mpl::eval_if<
  mpl::is_sequence< T >,
  mpl::identity< T >,
  mpl::identity< mpl::list< T > > > {};

//////////////////////////////////////////////////////////////////////////////
template< class MostDerived, class Context, class InnerInitial >
struct simple_state_base_type
{
  private:
    typedef typename Context::outermost_context_base_type::allocator_type
      allocator_type;
    typedef typename Context::outermost_context_base_type::rtti_policy_type
      rtti_policy_type;
    typedef typename detail::make_list< InnerInitial >::type
      inner_initial_list;
    typedef typename mpl::size< inner_initial_list >::type
      inner_initial_list_size;

  public:
    typedef typename mpl::eval_if<
      mpl::empty< inner_initial_list >,
      mpl::identity< typename rtti_policy_type::
        template rtti_derived_type< MostDerived, leaf_state<
          allocator_type,
          rtti_policy_type > > >,
      mpl::identity< typename rtti_policy_type::
        template rtti_derived_type< MostDerived, node_state<
          inner_initial_list_size,
          allocator_type,
          rtti_policy_type > > > >::type type;
};


//////////////////////////////////////////////////////////////////////////////
struct no_transition_function
{
  template< class CommonContext >
  void operator()( CommonContext & ) const {}
};

template< class TransitionContext, class Event >
class transition_function
{
  public:
    transition_function(
      void ( TransitionContext::*pTransitionAction )( const Event & ),
      const Event & evt
    ) :
      pTransitionAction_( pTransitionAction ),
      evt_( evt )
    {
    }

    template< class CommonContext >
    void operator()( CommonContext & commonContext ) const
    {
      ( commonContext.template context< TransitionContext >()
        .*pTransitionAction_ )( evt_ );
    }

  private:
    void ( TransitionContext::*pTransitionAction_ )( const Event & );
    const Event & evt_;
};


template< bool contextHasInheritedDeepHistory, bool contextHasDeepHistory >
struct deep_history_storer
{
  template< class HistorizedState, class LeafState, class Context >
  static void store_deep_history( Context & ) {}
};

template<>
struct deep_history_storer< true, false >
{
  template< class HistorizedState, class LeafState, class Context >
  static void store_deep_history( Context & ctx )
  {
    ctx.template store_deep_history_impl< LeafState >();
  }
};

template<>
struct deep_history_storer< true, true >
{
  template< class HistorizedState, class LeafState, class Context >
  static void store_deep_history( Context & ctx )
  {
    ctx.outermost_context_base().template store_deep_history<
      HistorizedState, LeafState >();
    ctx.template store_deep_history_impl< LeafState >();
  }
};



} // namespace detail



//////////////////////////////////////////////////////////////////////////////
enum history_mode
{
  has_no_history,
  has_shallow_history,
  has_deep_history,
  has_full_history // shallow & deep
};



//////////////////////////////////////////////////////////////////////////////
template< class MostDerived,
          class Context,
          class InnerInitial = mpl::list<>,
          history_mode historyMode = has_no_history >
class simple_state : public detail::simple_state_base_type< MostDerived,
  typename Context::inner_context_type, InnerInitial >::type
{
  typedef typename detail::simple_state_base_type<
    MostDerived, typename Context::inner_context_type,
    InnerInitial >::type base_type;

  public:
    //////////////////////////////////////////////////////////////////////////
    typedef mpl::list<> reactions;

    typedef typename Context::inner_context_type context_type;

    template< detail::orthogonal_position_type innerOrthogonalPosition >
    struct orthogonal
    {
      typedef mpl::integral_c<
        detail::orthogonal_position_type,
        innerOrthogonalPosition > inner_orthogonal_position;
      typedef MostDerived inner_context_type;
    };

    typedef typename context_type::outermost_context_type
      outermost_context_type;

    outermost_context_type & outermost_context()
    {
      // This assert fails when an attempt is made to access the state machine
      // from a constructor of a state that is *not* a subtype of state<>.
      // To correct this, derive from state<> instead of simple_state<>.
      BOOST_ASSERT( get_pointer( pContext_ ) != 0 );
      return pContext_->outermost_context();
    }

    const outermost_context_type & outermost_context() const
    {
      // This assert fails when an attempt is made to access the state machine
      // from a constructor of a state that is *not* a subtype of state<>.
      // To correct this, derive from state<> instead of simple_state<>.
      BOOST_ASSERT( get_pointer( pContext_ ) != 0 );
      return pContext_->outermost_context();
    }

    template< class OtherContext >
    OtherContext & context()
    {
      typedef typename mpl::if_<
        is_same< OtherContext, MostDerived >,
        context_impl_this_context,
        context_impl_other_context
      >::type impl;
      return impl::template context_impl< OtherContext >( *this );
    }

    template< class OtherContext >
    const OtherContext & context() const
    {
      typedef typename mpl::if_<
        is_same< OtherContext, MostDerived >,
        context_impl_this_context,
        context_impl_other_context
      >::type impl;
      return impl::template context_impl< OtherContext >( *this );
    }

    template< class Target >
    Target state_cast() const
    {
      return outermost_context_base().template state_cast< Target >();
    }

    template< class Target >
    Target state_downcast() const
    {
      return outermost_context_base().template state_downcast< Target >();
    }

    typedef typename context_type::state_base_type state_base_type;
    typedef typename context_type::state_iterator state_iterator;

    state_iterator state_begin() const
    {
      return outermost_context_base().state_begin();
    }

    state_iterator state_end() const
    {
      return outermost_context_base().state_end();
    }


    typedef typename context_type::event_base_ptr_type event_base_ptr_type;

    void post_event( const event_base_ptr_type & pEvent )
    {
      outermost_context_base().post_event( pEvent );
    }

    void post_event( const event_base & evt )
    {
      outermost_context_base().post_event( evt );
    }

    result discard_event()
    {
      return detail::result_utility::make_result( detail::do_discard_event );
    }

    result forward_event()
    {
      return detail::result_utility::make_result( detail::do_forward_event );
    }

    result defer_event()
    {
      this->state_base_type::defer_event();
      return detail::result_utility::make_result( detail::do_defer_event );
    }

    template< class DestinationState >
    result transit()
    {
      return transit_impl< DestinationState, outermost_context_type >(
        detail::no_transition_function() );
    }

    template< class DestinationState, class TransitionContext, class Event >
    result transit(
      void ( TransitionContext::*pTransitionAction )( const Event & ),
      const Event & evt )
    {
      return transit_impl< DestinationState, TransitionContext >(
        detail::transition_function< TransitionContext, Event >(
          pTransitionAction, evt ) );
    }

    result terminate()
    {
      outermost_context_base().terminate_as_reaction( *this );
      return detail::result_utility::make_result( detail::do_discard_event );
    }

    template<
      class HistoryContext,
      detail::orthogonal_position_type orthogonalPosition >
    void clear_shallow_history()
    {