/*******************************************************************************
    * SAT4J: a SATisfiability library for Java Copyright (C) 2004, 2012 Artois University and CNRS
    *
    * All rights reserved. This program and the accompanying materials
    * are made available under the terms of the Eclipse Public License v1.0
    * which accompanies this distribution, and is available at
    *  http://www.eclipse.org/legal/epl-v10.html
    *
    * Alternatively, the contents of this file may be used under the terms of
   * either the GNU Lesser General Public License Version 2.1 or later (the
   * "LGPL"), in which case the provisions of the LGPL are applicable instead
   * of those above. If you wish to allow use of your version of this file only
   * under the terms of the LGPL, and not to allow others to use your version of
   * this file under the terms of the EPL, indicate your decision by deleting
   * the provisions above and replace them with the notice and other provisions
   * required by the LGPL. If you do not delete the provisions above, a recipient
   * may use your version of this file under the terms of the EPL or the LGPL.
   *
   * Based on the original MiniSat specification from:
   *
   * An extensible SAT solver. Niklas Een and Niklas Sorensson. Proceedings of the
   * Sixth International Conference on Theory and Applications of Satisfiability
   * Testing, LNCS 2919, pp 502-518, 2003.
   *
   * See www.minisat.se for the original solver in C++.
   *
   * Contributors:
   *   CRIL - initial API and implementation
   *******************************************************************************/
  package org.sat4j.tools;
  
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.sat4j.specs.ContradictionException;
  import org.sat4j.specs.IConstr;
  import org.sat4j.specs.IGroupSolver;
  import org.sat4j.specs.ISolver;
  import org.sat4j.specs.IVecInt;
  
  public class GroupClauseSelectorSolver<T extends ISolver> extends
          AbstractClauseSelectorSolver<T> implements IGroupSolver {
  
      private static final long serialVersionUID = 1L;
  
      private final Map<Integer, Integer> varToHighLevel = new HashMap<Integer, Integer>();
      private final Map<Integer, Integer> highLevelToVar = new HashMap<Integer, Integer>();
  
      public GroupClauseSelectorSolver(T solver) {
          super(solver);
      }
  
      public IConstr addControlableClause(IVecInt literals, int desc)
              throws ContradictionException {
          if (desc == 0) {
              return super.addClause(literals);
          }
          Integer hlvar = this.highLevelToVar.get(desc);
          if (hlvar == null) {
              hlvar = createNewVar(literals);
              this.highLevelToVar.put(desc, hlvar);
              this.varToHighLevel.put(hlvar, desc);
          }
          literals.push(hlvar);
          return super.addClause(literals);
      }
  
      public IConstr addNonControlableClause(IVecInt literals)
              throws ContradictionException {
          return super.addClause(literals);
      }
  
      public IConstr addClause(IVecInt literals, int desc)
              throws ContradictionException {
          return addControlableClause(literals, desc);
      }
  
      @Override
      public Collection<Integer> getAddedVars() {
          return varToHighLevel.keySet();
      }
  
      @Override
      public int[] model() {
          int[] fullmodel = super.modelWithInternalVariables();
          if (fullmodel == null) {
              return null;
          }
          int[] model = new int[fullmodel.length - this.varToHighLevel.size()];
          int j = 0;
          for (int element : fullmodel) {
              if (this.varToHighLevel.get(Math.abs(element)) == null) {
                  model[j++] = element;
              }
          }
          return model;
      }
  
     public Map<Integer, Integer> getVarToHighLevel() {
         return varToHighLevel;
     }
 
 }