/**

  * 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.process.poc.krms.proposition;

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

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

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

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

 import org.kuali.student.r2.core.hold.dto.HoldInfo;

 import java.util.ArrayList;

 import java.util.Collections;

 import java.util.List;

 /**

  * This class represents a proposition to evaluate if a student has a Hold that would prevent registration

  *

  * @author alubbers

  */

 public class RegistrationHoldProposition extends AbstractLeafProposition {

     private final String issueKey;

     public RegistrationHoldProposition(String issueKey) {

         this.issueKey = issueKey;

     }

     @Override

     public PropositionResult evaluate(ExecutionEnvironment environment) {

         Term studentRegistrationHoldsTerm = new Term(RulesExecutionConstants.STUDENT_REGISTRATION_HOLDS_TERM_NAME, Collections.singletonMap(RulesExecutionConstants.ISSUE_KEY_TERM_PROPERTY, issueKey));

         List<HoldInfo> studentRegistrationHolds = environment.resolveTerm(studentRegistrationHoldsTerm, this);

         PropositionResult result = null;

         if(studentRegistrationHolds.isEmpty()) {

             result = new PropositionResult(true);

         }

         else {

             List<HoldInfo> blockingHolds = new ArrayList<HoldInfo>();

             List<HoldInfo> warningHolds = new ArrayList<HoldInfo>();

             // Split the found holds into warning and blocking holds

             for(HoldInfo hold : studentRegistrationHolds) {

                 if(hold.getIsWarning()) {

                     warningHolds.add(hold);

                 }

                 else {

                     blockingHolds.add(hold);

                 }

             }

             // if there are no blocking holds, the result of the evaluation is true

             result = new PropositionResult(blockingHolds.isEmpty());

             // check the warning holds, add the hold Ids to the environment attributes if any have been found for the student

             if(!warningHolds.isEmpty()) {

                 List<String> warningHoldIds = (List<String>) environment.getEngineResults().getAttribute(RulesExecutionConstants.REGISTRATION_HOLD_WARNINGS_ATTRIBUTE);

                 if(warningHoldIds == null) {

                     warningHoldIds = new ArrayList<String>(warningHolds.size());

                 }

                 for(HoldInfo hold : warningHolds) {

                     warningHoldIds.add(hold.getId());

                 }

                 environment.getEngineResults().setAttribute(RulesExecutionConstants.REGISTRATION_HOLD_WARNINGS_ATTRIBUTE, warningHoldIds);

             }

         }

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

         return result;

     }

 }