/**

  * Copyright 2010 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.search.service.impl;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.apache.log4j.Logger;

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

 import org.kuali.student.common.search.dto.SearchRequest;

 import org.kuali.student.common.search.dto.SearchResult;

 import org.kuali.student.common.search.dto.SearchTypeInfo;

 import org.kuali.student.common.search.service.SearchDispatcher;

 import org.kuali.student.common.search.service.SearchService;

 public class SearchDispatcherImpl implements SearchDispatcher{

         final Logger LOG = Logger.getLogger(SearchDispatcherImpl.class);

         private List<SearchService> services;

         //Map of search key->service

         private Map<String,SearchService> serviceMap = null;

         public SearchDispatcherImpl() {

                 super();

         }

         public SearchDispatcherImpl(SearchService... services){

                 super();

                 this.services = new ArrayList<SearchService>();

                 if(services!=null){

                         for(SearchService service:services){

                                 this.services.add(service);

                         }

                 }

         }

         public synchronized void init(){

                 if(serviceMap==null){

                         serviceMap = new HashMap<String,SearchService>();

                         //Look through each service, grab it's search keys and add them to the map

                         for(SearchService service:services){

                                 if(null==service){

                                         LOG.warn("Null service passed to SearchDelegator");

                                 }else{

                                         try {

                                                 List<SearchTypeInfo> searchTypes = service.getSearchTypes();

                                                 if(searchTypes!=null){

                                                         for(SearchTypeInfo searchType:searchTypes){

                                                                 serviceMap.put(searchType.getKey(),service);

                                                         }

                                                 }

                                         } catch (OperationFailedException e) {

                                                 LOG.warn("Error getting searchTypes",e);

                                         }

                                 }

                         }

                 }

         }

         /**

          * Delegates to the service responsible for the given search type key

          * @param searchRequest

          * @return The searchResult from the delegated search or null

          */

         public SearchResult dispatchSearch(SearchRequest searchRequest) {

                 //Lazy Load service map.  THis might cause synchronization issues?

                 //Needed because of circular bean dependencies... dispatch->serviceImpl->searchMgr->crossSvcMgr->dispatch

                 if(serviceMap==null){

                         init();

                 }

                 //Lookup which service to call for given search key and do the search

                 if(searchRequest != null){

                         String searchKey = searchRequest.getSearchKey();

                         SearchService searchService = serviceMap.get(searchKey);

                         if(searchService != null){

                                 SearchResult searchResult;

                                 try {

                                         searchResult = searchService.search(searchRequest);

                                 } catch (Exception e) {

                                         LOG.warn("Error invoking search",e);

                                         return null;

                                 }

                                 return searchResult;

                         }

                         LOG.error("Error Dispatching, Search Service not found for search key:"+searchRequest.getSearchKey());

                 }

                 return null;

         }

         public void setServices(List<SearchService> services) {

                 this.services = services;

         }

 }