/*

  * Copyright 2007-2008 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.opensource.org/licenses/ecl2.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.rice.kns.service.impl;

 import java.io.ByteArrayInputStream;

 import java.io.ByteArrayOutputStream;

 import java.io.ObjectInputStream;

 import java.io.ObjectOutputStream;

 import java.sql.Timestamp;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.Map;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.core.api.encryption.EncryptionService;

 import org.kuali.rice.core.api.services.CoreApiServiceLocator;

 import org.kuali.rice.kew.exception.WorkflowException;

 import org.kuali.rice.kew.util.KEWConstants;

 import org.kuali.rice.kns.UserSession;

 import org.kuali.rice.kns.bo.SessionDocument;

 import org.kuali.rice.kns.dao.SessionDocumentDao;

 import org.kuali.rice.kns.datadictionary.DocumentEntry;

 import org.kuali.rice.kns.service.BusinessObjectService;

 import org.kuali.rice.kns.service.DataDictionaryService;

 import org.kuali.rice.kns.service.KNSServiceLocatorWeb;

 import org.kuali.rice.kns.service.SessionDocumentService;

 import org.kuali.rice.kns.util.KualiLRUMap;

 import org.kuali.rice.kns.web.spring.form.DocumentFormBase;

 import org.kuali.rice.kns.web.struts.form.KualiDocumentFormBase;

 import org.kuali.rice.kns.workflow.service.KualiWorkflowDocument;

 import org.springframework.beans.factory.InitializingBean;

 import org.springframework.transaction.annotation.Transactional;

 /**

  * This class is the service implementation for a SessionDocument. This is

  * the default, Kuali delivered implementation.

  * 

  * @author Kuali Rice Team (rice.collab@kuali.org)

  *

  */

 @Transactional

 public class SessionDocumentServiceImpl implements SessionDocumentService, InitializingBean  {

     protected static final String IP_ADDRESS = "ipAddress";

         protected static final String PRINCIPAL_ID = "principalId";

         protected static final String DOCUMENT_NUMBER = "documentNumber";

         protected static final String SESSION_ID = "sessionId";

         private static org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(SessionDocumentServiceImpl.class);

     private BusinessObjectService businessObjectService;

     private DataDictionaryService dataDictionaryService;

     private SessionDocumentDao sessionDocumentDao;    

         private Map<String,CachedObject> cachedObjects;

         private EncryptionService encryptionService;

         private int maxCacheSize;

     public static class CachedObject {

         private UserSession userSession;

         private String formKey;

                 CachedObject(UserSession userSession, String formKey) {

                         this.userSession = userSession;

                         this.formKey = formKey;

                 }

                 @Override

         public String toString() {

                 return "CachedObject: principalId="+userSession.getPrincipalId()+" / objectWithFormKey="+userSession.retrieveObject(formKey);

         }

                 public UserSession getUserSession() {

                         return this.userSession;

                 }

                 public String getFormKey() {

                         return this.formKey;

                 }

     }

         @Override

         @SuppressWarnings("unchecked")

         public void afterPropertiesSet() throws Exception {

                 cachedObjects = Collections.synchronizedMap( new KualiLRUMap(maxCacheSize) );                

         }

         /**

      * @see org.kuali.rice.kns.service.SessionDocumentService#getDocumentForm(String documentNumber, String docFormKey, UserSession userSession)

      */

     @Override

         public KualiDocumentFormBase getDocumentForm( String documentNumber, String docFormKey, UserSession userSession, String ipAddress){

             KualiDocumentFormBase documentForm = null;

                 LOG.debug("getDocumentForm KualiDocumentFormBase from db");

                 try{

                         // re-create the KualiDocumentFormBase object

                         documentForm = (KualiDocumentFormBase)retrieveDocumentForm(userSession, userSession.getKualiSessionId(), documentNumber, ipAddress);

                         //re-store workFlowDocument into session

                         KualiWorkflowDocument workflowDocument = documentForm.getDocument().getDocumentHeader().getWorkflowDocument();

                         addDocumentToUserSession(userSession, workflowDocument);                                

                 } catch(Exception e) {

                     LOG.error("getDocumentForm failed for SessId/DocNum/PrinId/IP:"

                             + userSession.getKualiSessionId()+"/"+documentNumber+"/"+userSession.getPrincipalId()+"/"+ipAddress, e);

                 }

         return documentForm;

     }

         /**

          * @see org.kuali.rice.kns.service.SessionDocumentService#getUifDocumentForm(org.kuali.rice.kns.web.spring.form.DocumentFormBase, org.kuali.rice.kns.UserSession, java.lang.String)

          */

         @Override

         public DocumentFormBase getUifDocumentForm(String documentNumber, String docFormKey, UserSession userSession, String ipAddress) {

             DocumentFormBase documentForm = null;

                 LOG.debug("getDocumentForm KualiDocumentFormBase from db");

                 try{

                         // re-create the DocumentFormBase object

                         documentForm = (DocumentFormBase)retrieveDocumentForm(userSession, docFormKey, documentNumber, ipAddress);

                         //re-store workFlowDocument into session

                         KualiWorkflowDocument workflowDocument = documentForm.getDocument().getDocumentHeader().getWorkflowDocument();

                         addDocumentToUserSession(userSession, workflowDocument);                                

                 } catch(Exception e) {

                     LOG.error("getDocumentForm failed for SessId/DocNum/PrinId/IP:"

                             + userSession.getKualiSessionId()+"/"+documentNumber+"/"+userSession.getPrincipalId()+"/"+ipAddress, e);

                 }

         return documentForm;

         }

         protected Object retrieveDocumentForm(UserSession userSession, String sessionId, String documentNumber, String ipAddress) throws Exception{

                 HashMap<String, String> primaryKeys = new HashMap<String, String>(4);

                 primaryKeys.put(SESSION_ID, sessionId);

                 if (documentNumber != null){

                         primaryKeys.put(DOCUMENT_NUMBER, documentNumber);

                 }

                 primaryKeys.put(PRINCIPAL_ID, userSession.getPrincipalId());

                 primaryKeys.put(IP_ADDRESS, ipAddress);

                 SessionDocument sessionDoc = getBusinessObjectService().findByPrimaryKey(SessionDocument.class, primaryKeys);

                 if(sessionDoc != null){

                         byte[] formAsBytes = sessionDoc.getSerializedDocumentForm();

                         if ( sessionDoc.isEncrypted() ) {

                                 formAsBytes = getEncryptionService().decryptBytes(formAsBytes);

                         }

                         ByteArrayInputStream baip = new ByteArrayInputStream(formAsBytes);

                         ObjectInputStream ois = new ObjectInputStream(baip);

                         return ois.readObject();

                 }

                 return null;

         }

         @Override

         public KualiWorkflowDocument getDocumentFromSession(UserSession userSession, String docId) {

                 @SuppressWarnings("unchecked")

                 Map<String, KualiWorkflowDocument> workflowDocMap = (Map<String, KualiWorkflowDocument>) userSession.retrieveObject(KEWConstants.WORKFLOW_DOCUMENT_MAP_ATTR_NAME);

                 if (workflowDocMap == null) {

                         workflowDocMap = new HashMap<String,KualiWorkflowDocument>();

                         userSession.addObject(KEWConstants.WORKFLOW_DOCUMENT_MAP_ATTR_NAME, workflowDocMap);

                         return null;

                 }

                 return workflowDocMap.get(docId);

         }

         /**

          * @see org.kuali.rice.kns.service.SessionDocumentService#addDocumentToUserSession(org.kuali.rice.kns.UserSession, 

          *                 org.kuali.rice.kns.workflow.service.KualiWorkflowDocument)

          */

         @Override

         public void addDocumentToUserSession(UserSession userSession, KualiWorkflowDocument document) {

                 try {

                         @SuppressWarnings("unchecked")

                         Map<String, KualiWorkflowDocument> workflowDocMap = (Map<String, KualiWorkflowDocument>) userSession.retrieveObject(KEWConstants.WORKFLOW_DOCUMENT_MAP_ATTR_NAME);

                         if (workflowDocMap == null) {

                                 workflowDocMap = new HashMap<String,KualiWorkflowDocument>();

                         }

                         workflowDocMap.put(document.getDocumentId(), document);

                         userSession.addObject(KEWConstants.WORKFLOW_DOCUMENT_MAP_ATTR_NAME, workflowDocMap);

                 } catch (WorkflowException e) {

                         throw new IllegalStateException("could not save the document in the session", e);

                 }

         }

     /**

          * @see org.kuali.rice.kns.service.SessionDocumentService#purgeDocumentForm(String

          *      documentNumber, String docFormKey, UserSession userSession )

          */

         @Override

         public void purgeDocumentForm(String documentNumber, String docFormKey,

                         UserSession userSession, String ipAddress) {

                 synchronized (userSession) {

                 LOG.debug("purge document form from session");

                 userSession.removeObject(docFormKey);        

                         try {

                                 LOG.debug("purge document form from database");

                                 HashMap<String, String> primaryKeys = new HashMap<String, String>(4);

                                 primaryKeys.put(SESSION_ID, userSession.getKualiSessionId());

                                 primaryKeys.put(DOCUMENT_NUMBER, documentNumber);

                                 primaryKeys.put(PRINCIPAL_ID, userSession.getPrincipalId());

                                 primaryKeys.put(IP_ADDRESS, ipAddress);

                                 getBusinessObjectService().deleteMatching(SessionDocument.class, primaryKeys);

                         } catch (Exception e) {

                                 LOG.error("purgeDocumentForm failed for SessId/DocNum/PrinId/IP:"

                                 + userSession.getKualiSessionId()+"/"+documentNumber+"/"+userSession.getPrincipalId()+"/"+ipAddress, e);

                         }

                 }

         }

     /**

      * @see org.kuali.rice.kns.service.SessinoDocumentService#setDocumentForm()

      */

     @Override

         public void setDocumentForm(KualiDocumentFormBase form, UserSession userSession, String ipAddress){

             synchronized ( userSession ) { 

                     //formKey was set in KualiDocumentActionBase execute method

                         String formKey = form.getFormKey();

                         String key = userSession.getKualiSessionId() + "-" + formKey;

                         cachedObjects.put(key, new CachedObject( userSession, formKey ));

                 String documentNumber = form.getDocument().getDocumentNumber(); 

                     if( StringUtils.isNotBlank(documentNumber)) {

                             persistDocumentForm(form, userSession, ipAddress, userSession.getKualiSessionId(), documentNumber);

                     } else {

                             LOG.warn("documentNumber is null on form's document: " + form);

                     }

             }            

     }

     /**

      * @see org.kuali.rice.kns.service.SessionDocumentService#setDocumentForm(org.kuali.rice.kns.web.spring.form.DocumentFormBase,

      *                 org.kuali.rice.kns.UserSession, java.lang.String)

      */

     @Override

         public void setDocumentForm(DocumentFormBase form, UserSession userSession, String ipAddress){

             synchronized ( userSession ) { 

                     //formKey was set in KualiDocumentActionBase execute method

                         String formKey = form.getFormKey();

                         String key = userSession.getKualiSessionId() + "-" + formKey;

                         String documentNumber = form.getDocument().getDocumentNumber();

                         if( StringUtils.isNotBlank(formKey)) {

                                 //FIXME: Currently using formKey for sessionId

                                 persistDocumentForm(form, userSession, ipAddress, formKey, documentNumber);

                         } else {

                             LOG.warn("documentNumber is null on form's document: " + form);

                     }

             }            

     }

     protected void persistDocumentForm(Object form, UserSession userSession, String ipAddress, String sessionId, String documentNumber){

         try {

             LOG.debug("set Document Form into database");

             Timestamp currentTime = new Timestamp(System.currentTimeMillis());

             ByteArrayOutputStream baos = new ByteArrayOutputStream();

             ObjectOutputStream oos = new ObjectOutputStream(baos);

             oos.writeObject(form);

             // serialize the KualiDocumentFormBase object into a byte array

             byte[] formAsBytes = baos.toByteArray();

                         boolean encryptContent = false;

                         if ((form instanceof KualiDocumentFormBase) && ((KualiDocumentFormBase)form).getDocTypeName() != null ) {

                                 DocumentEntry documentEntry = getDataDictionaryService().getDataDictionary().getDocumentEntry( ((KualiDocumentFormBase)form).getDocTypeName() );

                                 if ( documentEntry != null ) {

                                         encryptContent = documentEntry.isEncryptDocumentDataInPersistentSessionStorage();

                                 }

                         }                                         

             if ( encryptContent ) {

                     formAsBytes = getEncryptionService().encryptBytes(formAsBytes);

             }

             // check if a record is already there in the database

             // this may only happen under jMeter testing, but there is no way to be sure

                         HashMap<String, String> primaryKeys = new HashMap<String, String>(4);

                         primaryKeys.put(SESSION_ID, sessionId);

                         primaryKeys.put(DOCUMENT_NUMBER, documentNumber);

                         primaryKeys.put(PRINCIPAL_ID, userSession.getPrincipalId());

                         primaryKeys.put(IP_ADDRESS, ipAddress);

                         SessionDocument sessionDocument = getBusinessObjectService().findByPrimaryKey(SessionDocument.class, primaryKeys);

                         if ( sessionDocument == null ) {

                                 sessionDocument = new SessionDocument();

                     sessionDocument.setSessionId(sessionId);

                         sessionDocument.setDocumentNumber(documentNumber);

                         sessionDocument.setPrincipalId(userSession.getPrincipalId());

                         sessionDocument.setIpAddress(ipAddress);

                         }

                         sessionDocument.setSerializedDocumentForm(formAsBytes);

                         sessionDocument.setEncrypted(encryptContent);

                 sessionDocument.setLastUpdatedDate(currentTime);

                     businessObjectService.save(sessionDocument);

         } catch(Exception e) {

                  final String className = form != null ? form.getClass().getName() : "null";

                  LOG.error("setDocumentForm failed for SessId/DocNum/PrinId/IP/class:"

                                  + userSession.getKualiSessionId()+"/"+documentNumber+"/"+userSession.getPrincipalId()+"/"+ipAddress+"/"+className , e);

         }            

     }

     /**

      * @see org.kuali.rice.kns.service.SessionDocumentService#purgeAllSessionDocuments(java.sql.Timestamp)

      */

     @Override

         public void purgeAllSessionDocuments(Timestamp expirationDate){

             sessionDocumentDao.purgeAllSessionDocuments(expirationDate);

     }        

     /**

          * @return the sessionDocumentDao

          */

         protected SessionDocumentDao getSessionDocumentDao() {

                 return this.sessionDocumentDao;

         }

         /**

          * @param sessionDocumentDao the sessionDocumentDao to set

          */

         public void setSessionDocumentDao(SessionDocumentDao sessionDocumentDao) {

                 this.sessionDocumentDao = sessionDocumentDao;

         }

         /**

          * @return the businessObjectService

          */

         protected BusinessObjectService getBusinessObjectService() {

                 return this.businessObjectService;

         }

         /**

          * @param businessObjectService the businessObjectService to set

          */

         public void setBusinessObjectService(BusinessObjectService businessObjectService) {

                 this.businessObjectService = businessObjectService;

         }

         /**

          * @return the maxCacheSize

          */

         public int getMaxCacheSize() {

                 return maxCacheSize;

         }

         /**

          * @param maxCacheSize the maxCacheSize to set

          */

         public void setMaxCacheSize(int maxCacheSize) {

                 this.maxCacheSize = maxCacheSize;

         }

         protected EncryptionService getEncryptionService() {

                 if ( encryptionService == null ) {

                         encryptionService = CoreApiServiceLocator.getEncryptionService();

                 }

                 return encryptionService;

         }

         protected DataDictionaryService getDataDictionaryService() {

                 if ( dataDictionaryService == null ) {

                         dataDictionaryService = KNSServiceLocatorWeb.getDataDictionaryService();

                 }

                 return dataDictionaryService;

         }

 }