/**

  * Copyright 2005-2011 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.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.krad.uif.service.impl;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.core.api.config.property.ConfigurationService;

 import org.kuali.rice.krad.service.KRADServiceLocator;

 import org.kuali.rice.krad.service.KRADServiceLocatorWeb;

 import org.kuali.rice.krad.service.LookupService;

 import org.kuali.rice.krad.uif.UifConstants;

 import org.kuali.rice.krad.uif.view.View;

 import org.kuali.rice.krad.uif.component.MethodInvokerConfig;

 import org.kuali.rice.krad.uif.field.InputField;

 import org.kuali.rice.krad.uif.field.AttributeQuery;

 import org.kuali.rice.krad.uif.field.AttributeQueryResult;

 import org.kuali.rice.krad.uif.service.AttributeQueryService;

 import org.kuali.rice.krad.uif.util.ObjectPropertyUtils;

 import org.kuali.rice.krad.uif.widget.Suggest;

 import org.kuali.rice.krad.util.BeanPropertyComparator;

 import java.text.MessageFormat;

 import java.util.ArrayList;

 import java.util.Collection;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 /**

  * Implementation of <code>AttributeQueryService</code> that prepares the attribute queries and

  * delegates to the <code>LookupService</code>

  *

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

  */

 public class AttributeQueryServiceImpl implements AttributeQueryService {

     private LookupService lookupService;

     private ConfigurationService configurationService;

     /**

      * @see org.kuali.rice.krad.uif.service.AttributeQueryService#performFieldSuggestQuery(

      *org.kuali.rice.krad.uif.view.View, java.lang.String, java.lang.String, java.util.Map<java.lang.String,

      *      java.lang.String>)

      */

     @Override

     public AttributeQueryResult performFieldSuggestQuery(View view, String fieldId, String fieldTerm,

             Map<String, String> queryParameters) {

         AttributeQueryResult queryResult = new AttributeQueryResult();

         // retrieve attribute field from view index

         InputField inputField = (InputField) view.getViewIndex().getComponentById(fieldId);

         if (inputField == null) {

             throw new RuntimeException("Unable to find attribute field instance for id: " + fieldId);

         }

         Suggest fieldSuggest = inputField.getFieldSuggest();

         AttributeQuery suggestQuery = fieldSuggest.getSuggestQuery();

         // add term as a like criteria

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

         additionalCriteria.put(fieldSuggest.getSourcePropertyName(), fieldTerm + "*");

         // execute suggest query

         Collection<?> results = null;

         if (suggestQuery.hasConfiguredMethod()) {

             Object queryMethodResult = executeAttributeQueryMethod(view, suggestQuery, queryParameters);

             if ((queryMethodResult != null) && (queryMethodResult instanceof Collection<?>)) {

                 results = (Collection<?>) queryMethodResult;

             }

         } else {

             results = executeAttributeQueryCriteria(suggestQuery, queryParameters, additionalCriteria);

         }

         // build list of suggest data from result records

         if (results != null) {

             List<String> suggestData = new ArrayList<String>();

             for (Object result : results) {

                 Object suggestFieldValue =

                         ObjectPropertyUtils.getPropertyValue(result, fieldSuggest.getSourcePropertyName());

                 if (suggestFieldValue != null) {

                     // TODO: need to apply formatter for field or have method in object property utils

                     suggestData.add(suggestFieldValue.toString());

                 }

             }

             queryResult.setResultData(suggestData);

         }

         return queryResult;

     }

     /**

      * @see org.kuali.rice.krad.uif.service.AttributeQueryService#performFieldQuery(org.kuali.rice.krad.uif.view.View,

      *      java.lang.String, java.util.Map<java.lang.String,java.lang.String>)

      */

     @Override

     public AttributeQueryResult performFieldQuery(View view, String fieldId, Map<String, String> queryParameters) {

         AttributeQueryResult queryResult = new AttributeQueryResult();

         // retrieve attribute field from view index

         InputField inputField = (InputField) view.getViewIndex().getComponentById(fieldId);

         if (inputField == null) {

             throw new RuntimeException("Unable to find attribute field instance for id: " + fieldId);

         }

         AttributeQuery fieldQuery = inputField.getFieldAttributeQuery();

         if (fieldQuery == null) {

             throw new RuntimeException("Field query not defined for field instance with id: " + fieldId);

         }

         // execute query and get result

         Object resultObject = null;

         if (fieldQuery.hasConfiguredMethod()) {

             Object queryMethodResult = executeAttributeQueryMethod(view, fieldQuery, queryParameters);

             if (queryMethodResult != null) {

                 // if method returned the result then no further processing needed

                 if (queryMethodResult instanceof AttributeQueryResult) {

                     return (AttributeQueryResult) queryMethodResult;

                 }

                 // if method returned collection, take first record

                 if (queryMethodResult instanceof Collection<?>) {

                     Collection<?> methodResultCollection = (Collection<?>) queryMethodResult;

                     if (!methodResultCollection.isEmpty()) {

                         resultObject = methodResultCollection.iterator().next();

                     }

                 } else {

                     resultObject = queryMethodResult;

                 }

             }

         } else {

             // execute field query as object lookup

             Collection<?> results = executeAttributeQueryCriteria(fieldQuery, queryParameters, null);

             if ((results != null) && !results.isEmpty()) {

                 // expect only one returned row for field query

                 if (results.size() > 1) {

                     //finding too many results in a not found message (not specific enough)

                     resultObject = null;

                 }

                 else{

                     resultObject = results.iterator().next();

                 }

             }

         }

         if (resultObject != null) {

             // build result field data map

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

             for (String fromField : fieldQuery.getReturnFieldMapping().keySet()) {

                 String returnField = fieldQuery.getReturnFieldMapping().get(fromField);

                 String fieldValueStr = "";

                 Object fieldValue = ObjectPropertyUtils.getPropertyValue(resultObject, fromField);

                 if (fieldValue != null) {

                     fieldValueStr = fieldValue.toString();

                 }

                 resultFieldData.put(returnField, fieldValueStr);

             }

             queryResult.setResultFieldData(resultFieldData);

             fieldQuery.setReturnMessageText("");

         } else {

             // add data not found message

             if (fieldQuery.isRenderNotFoundMessage()) {

                 String messageTemplate =

                         getConfigurationService().getPropertyValueAsString(

                                 UifConstants.MessageKeys.QUERY_DATA_NOT_FOUND);

                 String message = MessageFormat.format(messageTemplate, inputField.getLabel());

                 fieldQuery.setReturnMessageText(message.toLowerCase());

             }

         }

         // set message and message style classes on query result

         queryResult.setResultMessage(fieldQuery.getReturnMessageText());

         queryResult.setResultMessageStyleClasses(fieldQuery.getReturnMessageStyleClasses());

         return queryResult;

     }

     /**

      * Prepares the method configured on the attribute query then performs the method invocation

      *

      * @param view - view instance the field is contained within

      * @param attributeQuery - attribute query instance to execute

      * @param queryParameters - map of query parameters that provide values for the method arguments

      * @return Object type depends on method being invoked, could be AttributeQueryResult in which

      *         case the method has prepared the return result, or an Object that needs to be parsed for the result

      */

     protected Object executeAttributeQueryMethod(View view, AttributeQuery attributeQuery,

             Map<String, String> queryParameters) {

         String queryMethodToCall = attributeQuery.getQueryMethodToCall();

         MethodInvokerConfig queryMethodInvoker = attributeQuery.getQueryMethodInvokerConfig();

         if (queryMethodInvoker == null) {

             queryMethodInvoker = new MethodInvokerConfig();

         }

         // if method not set on invoker, use queryMethodToCall, note staticMethod could be set(don't know since

         // there is not a getter), if so it will override the target method in prepare

         if (StringUtils.isBlank(queryMethodInvoker.getTargetMethod())) {

             queryMethodInvoker.setTargetMethod(queryMethodToCall);

         }

         // if target class or object not set, use view helper service

         if ((queryMethodInvoker.getTargetClass() == null) && (queryMethodInvoker.getTargetObject() == null)) {

             queryMethodInvoker.setTargetObject(view.getViewHelperService());

         }

         // setup query method arguments

         Object[] arguments = null;

         if ((attributeQuery.getQueryMethodArgumentFieldList() != null) &&

                 (!attributeQuery.getQueryMethodArgumentFieldList().isEmpty())) {

             // retrieve argument types for conversion

             Class[] argumentTypes = queryMethodInvoker.getArgumentTypes();

             if ((argumentTypes == null) ||

                     (argumentTypes.length != attributeQuery.getQueryMethodArgumentFieldList().size())) {

                 throw new RuntimeException(

                         "Query method argument field list size does not match found method argument list size");

             }

             arguments = new Object[attributeQuery.getQueryMethodArgumentFieldList().size()];

             for (int i = 0; i < attributeQuery.getQueryMethodArgumentFieldList().size(); i++) {

                 String methodArgumentFromField = attributeQuery.getQueryMethodArgumentFieldList().get(i);

                 if (queryParameters.containsKey(methodArgumentFromField)) {

                     arguments[i] = queryParameters.get(methodArgumentFromField);

                 } else {

                     arguments[i] = null;

                 }

             }

         }

         queryMethodInvoker.setArguments(arguments);

         try {

             queryMethodInvoker.prepare();

             return queryMethodInvoker.invoke();

         } catch (Exception e) {

             throw new RuntimeException("Unable to invoke query method: " + queryMethodInvoker.getTargetMethod(), e);

         }

     }

     /**

      * Prepares a query using the configured data object, parameters, and criteria, then executes

      * the query and returns the result Collection

      *

      * @param attributeQuery - attribute query instance to perform query for

      * @param queryParameters - map of parameters that will be used in the query criteria

      * @param additionalCriteria - map of additional name/value pairs to add to the critiera

      * @return Collection<?> results of query

      */

     protected Collection<?> executeAttributeQueryCriteria(AttributeQuery attributeQuery,

             Map<String, String> queryParameters, Map<String, String> additionalCriteria) {

         Collection<?> results = null;

         // build criteria for query

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

         for (String fieldName : attributeQuery.getQueryFieldMapping().values()) {

             if (queryParameters.containsKey(fieldName) && StringUtils.isNotBlank(queryParameters.get(fieldName))) {

                 queryCriteria.put(fieldName, queryParameters.get(fieldName));

             }

         }

         // add any static criteria

         for (String fieldName : attributeQuery.getAdditionalCriteria().keySet()) {

             queryCriteria.put(fieldName, attributeQuery.getAdditionalCriteria().get(fieldName));

         }

         // add additional criteria

         if (additionalCriteria != null) {

             queryCriteria.putAll(additionalCriteria);

         }

         Class<?> queryClass = null;

         try {

             queryClass = Class.forName(attributeQuery.getDataObjectClassName());

         } catch (ClassNotFoundException e) {

             throw new RuntimeException(

                     "Invalid data object class given for suggest query: " + attributeQuery.getDataObjectClassName(), e);

         }

         // run query

         results = getLookupService().findCollectionBySearchUnbounded(queryClass, queryCriteria);

         // sort results

         if (!attributeQuery.getSortPropertyNames().isEmpty() && (results != null) && (results.size() > 1)) {

             Collections.sort((List<?>) results, new BeanPropertyComparator(attributeQuery.getSortPropertyNames()));

         }

         return results;

     }

     protected LookupService getLookupService() {

         if (lookupService == null) {

             lookupService = KRADServiceLocatorWeb.getLookupService();

         }

         return lookupService;

     }

     public void setLookupService(LookupService lookupService) {

         this.lookupService = lookupService;

     }

     protected ConfigurationService getConfigurationService() {

         if (configurationService == null) {

             configurationService = KRADServiceLocator.getKualiConfigurationService();

         }

         return configurationService;

     }

     public void setConfigurationService(ConfigurationService configurationService) {

         this.configurationService = configurationService;

     }

 }