/*

  * Copyright 2008 The Kuali Foundation

  *

  * Licensed under the Educational Community License, Version 1.0 (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.opensource.org/licenses/ecl1.php

  *

  * 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.lum.course.service.assembler;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import java.util.Map.Entry;

 import org.apache.log4j.Logger;

 import org.kuali.student.common.util.UUIDHelper;

 import org.kuali.student.core.assembly.BOAssembler;

 import org.kuali.student.core.assembly.BaseDTOAssemblyNode;

 import org.kuali.student.core.assembly.BaseDTOAssemblyNode.NodeOperation;

 import org.kuali.student.core.assembly.data.AssemblyException;

 import org.kuali.student.core.exceptions.DoesNotExistException;

 import org.kuali.student.core.exceptions.InvalidParameterException;

 import org.kuali.student.core.exceptions.MissingParameterException;

 import org.kuali.student.core.exceptions.OperationFailedException;

 import org.kuali.student.lum.course.dto.ActivityInfo;

 import org.kuali.student.lum.course.dto.CourseInfo;

 import org.kuali.student.lum.course.dto.FormatInfo;

 import org.kuali.student.lum.lu.dto.CluCluRelationInfo;

 import org.kuali.student.lum.lu.dto.CluInfo;

 import org.kuali.student.lum.lu.service.LuService;

 /**

  * Assembler for FormatInfo. Assembles/Disassemble FormatInfo from CluInfo and

  * other structures.

  * 

  * @author Kuali Student Team

  * 

  */

 public class FormatAssembler implements BOAssembler<FormatInfo, CluInfo> {

         final static Logger LOG = Logger.getLogger(FormatAssembler.class);

         private BOAssembler<ActivityInfo, CluInfo> activityAssembler;

         private LuService luService;

         @Override

         public FormatInfo assemble(CluInfo clu, FormatInfo formatInfo,

                         boolean shallowBuild) throws AssemblyException {

                 if (clu == null) {

                         return null;

                 }

                 FormatInfo format = (null != formatInfo) ? formatInfo

                                 : new FormatInfo();

                 // Copy base properties

                 format.setId(clu.getId());

                 format.setType(clu.getType());

                 format.setState(clu.getState());

                 format.setMetaInfo(clu.getMetaInfo());

                 format.setAttributes(clu.getAttributes());

                 // Don't make any changes to nested datastructures if this is

                 if (!shallowBuild) {

                         // Use the luService to find activities, then convert and add to the

                         // format

                         try {

                                 List<CluInfo> activities = luService.getRelatedClusByCluId(

                                                 format.getId(),

                                                 CourseAssemblerConstants.COURSE_ACTIVITY_RELATION_TYPE);

                                 for (CluInfo activity : activities) {

                                         ActivityInfo activityInfo = activityAssembler.assemble(

                                                         activity, null, false);

                                         format.getActivities().add(activityInfo);

                                 }

                         } catch (DoesNotExistException e) {

                         } catch (Exception e) {

                                 throw new AssemblyException("Error getting related activities", e);

                         } 

                 }

                 return format;

         }

         @Override

         public BaseDTOAssemblyNode<FormatInfo, CluInfo> disassemble(

                         FormatInfo format, NodeOperation operation)

                         throws AssemblyException {

                 BaseDTOAssemblyNode<FormatInfo, CluInfo> result = new BaseDTOAssemblyNode<FormatInfo, CluInfo>(

                                 this);

                 if (format == null) {

                         // FIXME Unsure now if this is an exception or just return null or

                         // empty assemblyNode

                         throw new AssemblyException("Format can not be null");

                 }

                 if (NodeOperation.CREATE != operation && null == format.getId()) {

                         throw new AssemblyException("Course Format Shell's id can not be null");

                 }

                 CluInfo clu;

         try {

             clu = (NodeOperation.UPDATE == operation) ? clu = luService.getClu(format.getId()) : new CluInfo();

         } catch (Exception e) {

             throw new AssemblyException("Error retrieving course format shell during update", e);

         } 

                 // Copy all fields

                 clu.setId(UUIDHelper.genStringUUID(format.getId()));// Create the id if

                                                                                                                         // it's not there

                                                                                                                         // already(important

                                                                                                                         // for creating

                                                                                                                         // relations)

                 clu.setType(CourseAssemblerConstants.COURSE_FORMAT_TYPE);

                 clu.setState(format.getState());

                 clu.setMetaInfo(format.getMetaInfo());

                 clu.setAttributes(format.getAttributes());

                 // Add the Clu to the result

                 result.setNodeData(clu);

                 result.setOperation(operation);

                 result.setBusinessDTORef(format);

                 // Use the Activity assembler to disassemble the activities and

                 // relations

                 List<BaseDTOAssemblyNode<?, ?>> activityResults;

         try {

             activityResults = disassembleActivities(clu.getId(),

                             format, operation);

             result.getChildNodes().addAll(activityResults);

         } catch (Exception e) {

             throw new AssemblyException("Error while disassembling format", e);

         }

                 return result;

         }

         /**

          * This method will return assembly nodes representing activities and

          * activity->format relations for a format based on the operation CREATE:

          * all activities and format-> activity relations will be created UPDATE:

          * activities will be taken from the luService and compared with the

          * incomming format's activities. Any new activites will be created with a

          * corresponding CluCluRelation Any existing activities will be Updated All

          * leftover activities and their CluCluRelations will be deleted DELETE: all

          * activities and their CluCluRelations will be deleted

          * 

          * If the Operation

          * 

          * @param format

          * @param result

          * @param operation

          * @return List of Assembly nodes

          * @throws AssemblyException

          * @throws OperationFailedException 

          * @throws MissingParameterException 

          * @throws InvalidParameterException 

          * @throws DoesNotExistException 

          */

         private List<BaseDTOAssemblyNode<?, ?>> disassembleActivities(String nodeId,

                         FormatInfo format, NodeOperation operation)

                         throws AssemblyException, DoesNotExistException, InvalidParameterException, MissingParameterException, OperationFailedException {

                 List<BaseDTOAssemblyNode<?, ?>> results = new ArrayList<BaseDTOAssemblyNode<?, ?>>();

                 // Get the current activities and put them in a map of activity

                 // id/relation id

                 Map<String, String> currentActivityIds = new HashMap<String, String>();

                 if (!NodeOperation.CREATE.equals(operation)) {

                         try {

                                 List<CluCluRelationInfo> activityRelationships = luService

                                                 .getCluCluRelationsByClu(format.getId());

                                 for (CluCluRelationInfo activityRelation : activityRelationships) {

                                         if (CourseAssemblerConstants.COURSE_ACTIVITY_RELATION_TYPE

                                                         .equals(activityRelation.getType())) {

                                                 currentActivityIds.put(activityRelation

                                                                 .getRelatedCluId(), activityRelation.getId());

                                         }

                                 }

                         } catch (DoesNotExistException e) {

                         } catch (Exception e) {

                                 throw new AssemblyException("Error getting related activities",        e);

                         }

                 }

                 // Loop through all the activities in this format

                 for (ActivityInfo activity : format.getActivities()) {

                         // If this is a format create/new activity update then all activities will be created

                     if (NodeOperation.CREATE == operation

                             || (NodeOperation.UPDATE == operation &&  !currentActivityIds.containsKey(activity.getId()))) {

                 // the activity does not exist, so create

                 // Assemble and add the activity

                 BaseDTOAssemblyNode<ActivityInfo, CluInfo> activityNode = activityAssembler

                         .disassemble(activity, NodeOperation.CREATE);

                 results.add(activityNode);

                 // Create the relationship and add it as well

                 CluCluRelationInfo relation = new CluCluRelationInfo();

                 relation.setCluId(nodeId);

                 relation.setRelatedCluId(activityNode.getNodeData().getId());// this should

                                                             // already be set

                                                             // even if it's a

                                                             // create

                 relation

                         .setType(CourseAssemblerConstants.COURSE_ACTIVITY_RELATION_TYPE);

                 relation.setState(format.getState());

                 BaseDTOAssemblyNode<FormatInfo, CluCluRelationInfo> relationNode = new BaseDTOAssemblyNode<FormatInfo, CluCluRelationInfo>(

                         null);

                 relationNode.setNodeData(relation);

                 relationNode.setOperation(NodeOperation.CREATE);

                 results.add(relationNode);

             } else if (NodeOperation.UPDATE == operation

                                         && currentActivityIds.containsKey(activity.getId())) {

                                 // If the format already has this activity, then just update the

                                 // activity

                                 BaseDTOAssemblyNode<ActivityInfo, CluInfo> activityNode = activityAssembler

                                                 .disassemble(activity, NodeOperation.UPDATE);

                                 results.add(activityNode);

                                 // remove this entry from the map so we can tell what needs to

                                 // be deleted at the end

                                 currentActivityIds.remove(activity.getId());

                         } else if (NodeOperation.DELETE == operation

                     && currentActivityIds.containsKey(activity.getId())) {

                 // Delete the Format and its relation

                 CluCluRelationInfo relationToDelete = new CluCluRelationInfo();

                 relationToDelete.setId( currentActivityIds.get(activity.getId()) );

                 BaseDTOAssemblyNode<CourseInfo, CluCluRelationInfo> relationToDeleteNode = new BaseDTOAssemblyNode<CourseInfo, CluCluRelationInfo>(

                         null);

                 relationToDeleteNode.setNodeData(relationToDelete);

                 relationToDeleteNode.setOperation(NodeOperation.DELETE);

                 results.add(relationToDeleteNode);

                 BaseDTOAssemblyNode<ActivityInfo, CluInfo> formatNode = activityAssembler

                 .disassemble(activity, NodeOperation.DELETE);

                 results.add(formatNode);                                

                 // remove this entry from the map so we can tell what needs to

                 // be deleted at the end

                 currentActivityIds.remove(activity.getId());                            

                         }

                 }         

         // Now any leftover activity ids are no longer needed, so delete

         // activities and relations

         for (Entry<String, String> entry : currentActivityIds.entrySet()) {

             // Create a new relation with the id of the relation we want to

             // delete

             CluCluRelationInfo relationToDelete = new CluCluRelationInfo();

             relationToDelete.setId(entry.getValue());

             BaseDTOAssemblyNode<FormatInfo, CluCluRelationInfo> relationToDeleteNode = new BaseDTOAssemblyNode<FormatInfo, CluCluRelationInfo>(

                     null);

             relationToDeleteNode.setNodeData(relationToDelete);

             relationToDeleteNode.setOperation(NodeOperation.DELETE);

             results.add(relationToDeleteNode);

             CluInfo activityCluToDelete = luService.getClu(entry.getKey());

             ActivityInfo activityToDelete = activityAssembler.assemble(activityCluToDelete, null, false);

             BaseDTOAssemblyNode<ActivityInfo, CluInfo> activityNode = activityAssembler

             .disassemble(activityToDelete, NodeOperation.DELETE);

             results.add(activityNode);                                            

         }

                 return results;

         }

         public BOAssembler<ActivityInfo, CluInfo> getActivityAssembler() {

                 return activityAssembler;

         }

         public void setActivityAssembler(

                         BOAssembler<ActivityInfo, CluInfo> activityAssembler) {

                 this.activityAssembler = activityAssembler;

         }

         public LuService getLuService() {

                 return luService;

         }

         public void setLuService(LuService luService) {

                 this.luService = luService;

         }

 }