/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
 *  Main authors:
 *     Christian Schulte <schulte@gecode.org>
 *
 *  Copyright:
 *     Christian Schulte, 2013
 *
 *  This file is part of Gecode, the generic constraint
 *  development environment:
 *     http://www.gecode.org
 *
 *  Permission is hereby granted, free of charge, to any person obtaining
 *  a copy of this software and associated documentation files (the
 *  "Software"), to deal in the Software without restriction, including
 *  without limitation the rights to use, copy, modify, merge, publish,
 *  distribute, sublicense, and/or sell copies of the Software, and to
 *  permit persons to whom the Software is furnished to do so, subject to
 *  the following conditions:
 *
 *  The above copyright notice and this permission notice shall be
 *  included in all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

#ifndef GECODE_SEARCH_NOGOODS_HH
#define GECODE_SEARCH_NOGOODS_HH

#include <gecode/search.hh>

namespace Gecode { namespace Search {

  /// Class for a sentinel no-good literal
  class GECODE_VTABLE_EXPORT NoNGL : public NGL {
  public:
    /// Constructor for creation
    NoNGL(void);
    /// Constructor for creation
    NoNGL(Space& home);
    /// Constructor for cloning \a ngl
    NoNGL(Space& home, NoNGL& ngl);
    /// Subscribe propagator \a p to all views of the no-good literal
    virtual void subscribe(Space& home, Propagator& p);
    /// Schedule propagator \a p for all views of the no-good literal
    virtual void reschedule(Space& home, Propagator& p);
    /// Cancel propagator \a p from all views of the no-good literal
    virtual void cancel(Space& home, Propagator& p);
    /// Test the status of the no-good literal
    virtual NGL::Status status(const Space& home) const;
    /// Propagate the negation of the no-good literal
    virtual ExecStatus prune(Space& home);
    /// Create copy
    virtual NGL* copy(Space& home);
  };

  /// No-good propagator
  class GECODE_SEARCH_EXPORT NoGoodsProp : public Propagator {
  protected:
    /// Root of no-good literal tree
    NGL* root;
    /// Number of no-good literals with subscriptions
    unsigned int n;
    /// Constructor for creation
    NoGoodsProp(Space& home, NGL* root);
    /// Constructor for cloning \a p
    NoGoodsProp(Space& home, NoGoodsProp& p);
  public:
    /// Perform copying during cloning
    virtual Actor* copy(Space& home);
    /// Const function (defined as low unary)
    virtual PropCost cost(const Space& home, const ModEventDelta& med) const;
    /// Schedule function
    virtual void reschedule(Space& home);
    /// Perform propagation
    virtual ExecStatus propagate(Space& home, const ModEventDelta& med);
    /// Post propagator for path \a p
    template<class Path>
    static ExecStatus post(Space& home, const Path& p);
    /// Delete propagator and return its size
    virtual size_t dispose(Space& home);
  };

}}

#include <gecode/search/nogoods.hpp>

#endif

// STATISTICS: search-other