package org.kuali.student.lum.program.server.transform;

 import java.util.List;

 import java.util.Map;

 import org.kuali.student.common.ui.client.mvc.DataModelDefinition;

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

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

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

 import org.kuali.student.core.assembly.data.Data.DataType;

 import org.kuali.student.core.assembly.data.Data.StringKey;

 import org.kuali.student.core.assembly.transform.AbstractDataFilter;

 import org.kuali.student.core.assembly.transform.MetadataFilter;

 import org.kuali.student.lum.program.client.ProgramConstants;

 import org.kuali.student.lum.program.dto.MajorDisciplineInfo;

 import org.kuali.student.lum.program.dto.ProgramVariationInfo;

 import org.kuali.student.lum.program.service.ProgramService;

 /**

  * When program is activated this filter sets the previous version to superseded and updates the end program

  * entry and and enroll terms. 

  * 

  * @author Will

  *

  */

 public class VersionProgramFilter extends AbstractDataFilter implements MetadataFilter{

         public static final String PREVIOUS_VERSION_DATA = "VersionProgramFilter.PreviousVersionData";

         public static final String PREVIOUS_VERSION_INFO = "previousVersionInfo";

         private Metadata previousVersionMetadata;

         protected ProgramService programService; 

         /**

          * Save previousVersionInfo from incoming data to be used by outbound filter

          */

         @Override

         public void applyInboundDataFilter(Data data, Metadata metadata,

                         Map<String, Object> properties) throws Exception {

                 Data previousVersionData = data.query(PREVIOUS_VERSION_INFO);

                 data.remove(new StringKey(PREVIOUS_VERSION_INFO));

                 if (previousVersionData != null){        

                         properties.put(PREVIOUS_VERSION_DATA, previousVersionData);

                 }                        

         }

         /**

          * Adds previous version information to the data if it exists and updates the previous version state

          * if state changed (this happens when program is activated)

          */

         @Override

         public void applyOutboundDataFilter(Data data, Metadata metadata,

                         Map<String, Object> properties) throws Exception {

                 Data previousVersionData = (Data)properties.get(PREVIOUS_VERSION_DATA);

                 String versionFromId = data.query(ProgramConstants.VERSION_FROM_ID);

                 if (versionFromId != null){

                         MajorDisciplineInfo previousVersionMajorInfo = programService.getMajorDiscipline(versionFromId);

                         if (previousVersionData == null){

                                 //This is an initial get. Create previous version data to send back to client 

                                 previousVersionData = new Data();

                                 previousVersionData.set(ProgramConstants.ID, previousVersionMajorInfo.getId());

                                 previousVersionData.set(ProgramConstants.END_PROGRAM_ENTRY_TERM, previousVersionMajorInfo.getEndProgramEntryTerm());

                                 previousVersionData.set(ProgramConstants.END_PROGRAM_ENROLL_TERM, previousVersionMajorInfo.getEndTerm());

                                 previousVersionData.set(ProgramConstants.STATE, previousVersionMajorInfo.getState());

                         } else {

                                 //This is a save operation. Check state field change for previous version state, indicating an "Activate" action,

                                 //which requires updating previous program with new states and end terms and setting activated program

                                 //to be the current version.

                                 String state = previousVersionData.get(ProgramConstants.STATE);

                                 if (state!= null && !state.equals(previousVersionMajorInfo.getState())){

                                         //Update previous program version with new state and terms

                                         String endEntryTerm = previousVersionData.get(ProgramConstants.END_PROGRAM_ENTRY_TERM); 

                                         String endEnrollTerm = previousVersionData.get(ProgramConstants.END_PROGRAM_ENROLL_TERM);

                                         previousVersionMajorInfo.setState(state);

                                         previousVersionMajorInfo.setEndProgramEntryTerm(endEntryTerm);

                                         previousVersionMajorInfo.setEndTerm(endEnrollTerm);

                                         //Update states on all variations for this program

                                 List<ProgramVariationInfo> variationList = previousVersionMajorInfo.getVariations();

                                 for (ProgramVariationInfo variation:variationList){

                                         variation.setState(state);                                        

                                 }

                                         programService.updateMajorDiscipline(previousVersionMajorInfo);

                                         //Set "activated" program to be the current version

                                         String activatedMajorId = data.get(ProgramConstants.ID);

                                         programService.setCurrentMajorDisciplineVersion(activatedMajorId, null);

                                 }

                         }

                         data.set(PREVIOUS_VERSION_INFO, previousVersionData);

                 }                

         }

         /**

          * Adds previousVersionInfo metadata to metadata returned to client

          */

         @Override

         public void applyMetadataFilter(String dtoName, Metadata metadata,

                         Map<String, Object> filterProperties) {                

                 metadata.getProperties().put(PREVIOUS_VERSION_INFO, getPreviousVersionMetadata(metadata));

         }

         /**

          * This generates a phantom "previousVersionInfo" metadata using dictionary definitions for fields already

          * defined for majorDisicplineInfo.

          * 

          * @param metadata

          * @return

          */

         protected Metadata getPreviousVersionMetadata(Metadata metadata){

                 if (previousVersionMetadata == null){

                         DataModelDefinition modelDef = new DataModelDefinition(metadata);

                         Metadata programIdMeta = modelDef.getMetadata(QueryPath.parse(ProgramConstants.ID));

                         Metadata programStateMeta = modelDef.getMetadata(QueryPath.parse(ProgramConstants.STATE));

                         Metadata endEntryTermMeta = modelDef.getMetadata(QueryPath.parse(ProgramConstants.END_PROGRAM_ENTRY_TERM));

                         Metadata endEnrollTermMeta = modelDef.getMetadata(QueryPath.parse(ProgramConstants.END_PROGRAM_ENROLL_TERM));

                         previousVersionMetadata = new Metadata();

                         previousVersionMetadata.setDataType(DataType.DATA);

                         Map<String, Metadata> properties = previousVersionMetadata.getProperties();

                         properties.put(ProgramConstants.ID, programIdMeta);

                         properties.put(ProgramConstants.STATE, programStateMeta);

                         properties.put(ProgramConstants.END_PROGRAM_ENTRY_TERM, endEntryTermMeta);

                         properties.put(ProgramConstants.END_PROGRAM_ENROLL_TERM, endEnrollTermMeta);

                 }

                 return previousVersionMetadata;

         }

         public void setProgramService(ProgramService programService) {

                 this.programService = programService;

         }        

 }