/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
 *  Main authors:
 *     Christian Schulte <schulte@gecode.org>
 *
 *  Copyright:
 *     Christian Schulte, 2009
 *
 *  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_SEQ_DFS_HH
#define GECODE_SEARCH_SEQ_DFS_HH

#include <gecode/search.hh>
#include <gecode/search/support.hh>
#include <gecode/search/worker.hh>
#include <gecode/search/seq/path.hh>

namespace Gecode { namespace Search { namespace Seq {

  /// Depth-first search engine implementation
  template<class Tracer>
  class DFS : public Worker {
  private:
    /// Search tracer
    Tracer tracer;
    /// Search options
    Options opt;
    /// Current path ins search tree
    Path<Tracer> path;
    /// Current space being explored
    Space* cur;
    /// Distance until next clone
    unsigned int d;
  public:
    /// Initialize for space \a s with options \a o
    DFS(Space* s, const Options& o);
    /// %Search for next solution
    Space* next(void);
    /// Return statistics
    Statistics statistics(void) const;
    /// Constrain future solutions to be better than \a b (should never be called)
    void constrain(const Space& b);
    /// Reset engine to restart at space \a s
    void reset(Space* s);
    /// Return no-goods
    NoGoods& nogoods(void);
    /// Destructor
    ~DFS(void);
  };

}}}

#include <gecode/search/seq/dfs.hpp>

#endif

// STATISTICS: search-seq