/**

  * Copyright 2011 The Kuali Foundation Licensed under the

  * Educational Community License, Version 2.0 (the "License"); you may

  * not use this file except in compliance with the License. You may

  * obtain a copy of the License at

  *

  * http://www.osedu.org/licenses/ECL-2.0

  *

  * Unless required by applicable law or agreed to in writing,

  * software distributed under the License is distributed on an "AS IS"

  * BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express

  * or implied. See the License for the specific language governing

  * permissions and limitations under the License.

  */

 package org.kuali.student.common.util.krms.proposition;

 import org.apache.commons.collections.CollectionUtils;

 import org.kuali.rice.krms.api.engine.ExecutionEnvironment;

 import org.kuali.rice.krms.api.engine.ResultEvent;

 import org.kuali.rice.krms.framework.engine.PropositionResult;

 import org.kuali.rice.krms.framework.engine.result.BasicResult;

 import org.kuali.student.common.util.krms.RulesExecutionConstants;

 import java.util.Collection;

 /**

  * Parent class for all course enrollment propositions

  *

  * @author alubbers

  */

 public abstract class CourseEnrollmentProposition extends AbstractLeafProposition {

     protected final boolean checkForAllEnrolled;

     protected Integer minToEnroll;

     public CourseEnrollmentProposition(Integer minToEnroll) {

         this.checkForAllEnrolled = false;

         this.minToEnroll = minToEnroll;

     }

     public CourseEnrollmentProposition() {

         checkForAllEnrolled = true;

     }

     @Override

     public PropositionResult evaluate(ExecutionEnvironment environment) {

         Collection<String> enrolledCourses = environment.resolveTerm(RulesExecutionConstants.enrolledCourseIdsTerm, this);

         Collection<String> requiredCourseIds = getRequiredCourseIds(environment);

         PropositionResult result = null;

         if(checkForAllEnrolled) {

             result = new PropositionResult(enrolledCourses.containsAll(requiredCourseIds));

         }

         else {

             result = new PropositionResult(CollectionUtils.intersection(enrolledCourses, requiredCourseIds).size() >= minToEnroll);

         }

         environment.getEngineResults().addResult(new BasicResult(ResultEvent.PROPOSITION_EVALUATED, this, environment, result.getResult()));

         return result;

     }

     protected abstract Collection<String> getRequiredCourseIds(ExecutionEnvironment environment);

 }