/*******************************************************************************
   * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2008 Daniel Le Berre
   *
   * 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 pseudo boolean algorithms described in:
  * A fast pseudo-Boolean constraint solver Chai, D.; Kuehlmann, A.
  * Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on
  * Volume 24, Issue 3, March 2005 Page(s): 305 - 317
  * 
  * and 
  * Heidi E. Dixon, 2004. Automating Pseudo-Boolean Inference within a DPLL 
  * Framework. Ph.D. Dissertation, University of Oregon.
  *******************************************************************************/
  package org.sat4j.pb.constraints;
  
  import java.math.BigInteger;
  
  import org.sat4j.minisat.constraints.AbstractDataStructureFactory;
  import org.sat4j.minisat.constraints.cnf.Clauses;
  import org.sat4j.minisat.constraints.cnf.LearntBinaryClause;
  import org.sat4j.minisat.constraints.cnf.LearntHTClause;
  import org.sat4j.minisat.constraints.cnf.Lits;
  import org.sat4j.minisat.constraints.cnf.UnitClause;
  import org.sat4j.minisat.core.Constr;
  import org.sat4j.minisat.core.ILits;
  import org.sat4j.pb.constraints.pb.AtLeastPB;
  import org.sat4j.pb.constraints.pb.BinaryClausePB;
  import org.sat4j.pb.constraints.pb.HTClausePB;
  import org.sat4j.pb.constraints.pb.IDataStructurePB;
  import org.sat4j.pb.constraints.pb.IInternalPBConstraintCreator;
  import org.sat4j.pb.constraints.pb.PBConstr;
  import org.sat4j.pb.core.PBDataStructureFactory;
  import org.sat4j.specs.ContradictionException;
  import org.sat4j.specs.IConstr;
  import org.sat4j.specs.IVec;
  import org.sat4j.specs.IVecInt;
  
  /**
   * @author leberre To change the template for this generated type comment go to
   *         Window>Preferences>Java>Code Generation>Code and Comments
   */
  public abstract class AbstractPBDataStructureFactory extends
          AbstractDataStructureFactory<ILits> implements PBDataStructureFactory<ILits>, IInternalPBConstraintCreator {
  
      /**
  	 * 
  	 */
  	private static final long serialVersionUID = 1L;
  
  	public Constr createClause(IVecInt literals) throws ContradictionException {
          IVecInt v = Clauses.sanityCheck(literals, getVocabulary(), solver);
          if (v == null)
              return null;
          if (v.size()==2)
          	return BinaryClausePB.brandNewClause(solver, getVocabulary(), v);
          return HTClausePB.brandNewClause(solver, getVocabulary(), v);
      }
  
      public Constr createUnregisteredClause(IVecInt literals) {
      	if (literals.size()==1)
      		return new UnitClause(literals.last());
      	if (literals.size()==2)
      		return new LearntBinaryClause(literals,getVocabulary());
          return new LearntHTClause(literals, getVocabulary());
      }
  
      @Override
      public Constr createCardinalityConstraint(IVecInt literals, int degree)
              throws ContradictionException {
          return AtLeastPB.atLeastNew(solver, getVocabulary(), literals, degree);
      }
  
      public Constr createPseudoBooleanConstraint(IVecInt literals,
              IVec<BigInteger> coefs, boolean moreThan, BigInteger degree)
              throws ContradictionException {
          return constraintFactory(literals, coefs, moreThan, degree);
      }
  
      /**
       * @param literals the literals
       * @param coefs the coefficients
       * @param moreThan 
       * @param degree the degree of the constraint
       * @return a new PB constraint
       */
     protected abstract PBConstr constraintFactory(IVecInt literals,
             IVecInt coefs, boolean moreThan, int degree)
             throws ContradictionException;
 
     protected abstract PBConstr constraintFactory(IDataStructurePB dspb);
 
     protected abstract PBConstr constraintFactory(IVecInt literals,
             IVec<BigInteger> coefs, boolean moreThan, BigInteger degree)
             throws ContradictionException;
 
     public Constr createUnregisteredPseudoBooleanConstraint(IVecInt literals,
             IVec<BigInteger> coefs, BigInteger degree) {
         return constraintFactory(literals, coefs, degree);
     }
 
     public Constr createUnregisteredPseudoBooleanConstraint(IDataStructurePB dspb) {
         return constraintFactory(dspb);
     }
 
     public IConstr createUnregisteredPseudoBooleanConstraint(IVecInt literals,
             IVec<BigInteger> coefs, boolean moreThan, BigInteger degree)
             throws ContradictionException {
         return constraintFactory(literals, coefs, moreThan, degree);
     }
 
     /**
      * @param literals
      * @param coefs
      * @param degree
      * @return a new PB constraint
      */
     protected abstract PBConstr constraintFactory(IVecInt literals,
             IVecInt coefs, int degree);
 
     protected abstract PBConstr constraintFactory(IVecInt literals,
             IVec<BigInteger> coefs, BigInteger degree);
 
     @Override
     protected ILits createLits() {
         return new Lits();
     }
 
 }