/*******************************************************************************
 * 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.minisat.constraints;

import org.sat4j.minisat.constraints.card.AtLeast;
import org.sat4j.minisat.constraints.cnf.Clauses;
import org.sat4j.minisat.constraints.cnf.LearntWLClause;
import org.sat4j.minisat.constraints.cnf.Lits;
import org.sat4j.minisat.constraints.cnf.OriginalBinaryClause;
import org.sat4j.minisat.constraints.cnf.OriginalWLClause;
import org.sat4j.minisat.constraints.cnf.UnitClause;
import org.sat4j.minisat.core.Constr;
import org.sat4j.minisat.core.ILits;
import org.sat4j.specs.ContradictionException;
import org.sat4j.specs.IVecInt;

/**
 * @author leberre
 * @since 2.1
 */
public class MixedDataStructureSingleWL extends AbstractDataStructureFactory {

    private static final long serialVersionUID = 1L;

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.sat4j.minisat.DataStructureFactory#createCardinalityConstraint(org
     * .sat4j.datatype.VecInt, int)
     */
    @Override
    public Constr createCardinalityConstraint(IVecInt literals, int degree)
            throws ContradictionException {
        return AtLeast.atLeastNew(this.solver, getVocabulary(), literals,
                degree);
    }

    @Override
    public Constr createUnregisteredCardinalityConstraint(IVecInt literals,
            int degree) {
        return new AtLeast(getVocabulary(), literals, degree);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.sat4j.minisat.DataStructureFactory#createClause(org.sat4j.datatype
     * .VecInt)
     */
    public Constr createClause(IVecInt literals) throws ContradictionException {
        IVecInt v = Clauses.sanityCheck(literals, getVocabulary(), this.solver);
        if (v == null) {
            // tautological clause
            return null;
        }
        if (v.size() == 1) {
            return new UnitClause(v.last());
        }
        if (v.size() == 2) {
            return OriginalBinaryClause.brandNewClause(this.solver,
                    getVocabulary(), v);
        }
        return OriginalWLClause.brandNewClause(this.solver, getVocabulary(), v);
    }

    public Constr createUnregisteredClause(IVecInt literals) {
        return new LearntWLClause(literals, getVocabulary());
    }

    @Override
    protected ILits createLits() {
        return new Lits();
    }
}
