/**

  * 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.ui.client.configurable.mvc.binding;

 import java.util.Iterator;

 import java.util.List;

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

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

 import org.kuali.student.common.ui.client.widgets.list.KSSelectItemWidgetAbstract;

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

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

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

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

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

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

 import com.google.gwt.user.client.ui.Widget;

 public class SelectItemWidgetBinding extends ModelWidgetBindingSupport<KSSelectItemWidgetAbstract> {

     public static SelectItemWidgetBinding INSTANCE = new SelectItemWidgetBinding();

     private SelectItemWidgetBinding() {}

     @Override

     public void setModelValue(KSSelectItemWidgetAbstract object, DataModel model, String path) {

         QueryPath qPath = QueryPath.parse(path);

         if (object.isMultipleSelect()) {

                 Data newValue = (Data)getWidgetValue(object).get();

             Data oldValue = model.get(qPath);

             if (!nullsafeEquals(oldValue, newValue)) {

                 model.set(qPath, newValue);

                 setDirtyFlag(model, qPath);

             }

         } else {

             String newValue = object.getSelectedItem();

             String oldValue = model.get(qPath);

             if (!nullsafeEquals(oldValue, newValue)) {

                 model.set(qPath, object.getSelectedItem());

                 setDirtyFlag(model, qPath);

             }

         }

     }

     @Override

     public void setWidgetValue(KSSelectItemWidgetAbstract object, final DataModel model, final String path) {

         QueryPath qPath = QueryPath.parse(path);

         Object value = model.get(qPath);

         setWidgetValue(object, value);

     }

     /**

      * Helper method get list item widget's values as a Data object

      * 

      * @param object

      * @param value

      * @return

      */

     public Value getWidgetValue(KSSelectItemWidgetAbstract object){

             Value value;

         if (object.isMultipleSelect()) {

                 Data data = new Data();

                 List<String> selectedItems = object.getSelectedItems();

                 for (String stringItem : selectedItems) {

                    data.add(stringItem);

                 }

                 value = new Data.DataValue(data);

         } else {

                 value = new Data.StringValue(object.getSelectedItem());

         }

         return value;

     }

     /**

      * Helper method to set Data object to a list item widget

      * @param object

      * @param value

      */

     public void setWidgetValue(KSSelectItemWidgetAbstract object, final Object value){

             Callback<Widget> selectListItemsCallback = new Callback<Widget>(){

             @Override

             public void exec(Widget widget) {

                 ((KSSelectItemWidgetAbstract)widget).clear();

                 if (value != null){

                         if (value instanceof String || value instanceof StringValue) {

                                 String itemId = (String)(value instanceof String ? value:((StringValue)value).get());

                             ((KSSelectItemWidgetAbstract)widget).selectItem(itemId);

                         } else if (value instanceof Data || value instanceof DataValue) {

                                 Data data = (Data)(value instanceof Data ? value:((DataValue)value).get());

                             for (Iterator itr = data.iterator(); itr.hasNext();) {

                                 Property p = (Property) itr.next();

                                 ((KSSelectItemWidgetAbstract)widget).selectItem((String) p.getValue());

                             }

                         }

                 }

             }            

         };

         if (!object.isInitialized()){

             object.addWidgetReadyCallback(selectListItemsCallback);

         } else{

             selectListItemsCallback.exec(object);

         }            

     }

 }