/**

  * 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.lum.common.client.widgets;

 import java.util.List;

 import org.kuali.student.common.ui.client.configurable.mvc.DefaultWidgetFactory;

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

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

 import org.kuali.student.common.ui.client.widgets.KSDropDown;

 import org.kuali.student.common.ui.client.widgets.impl.KSDropDownImpl;

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

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

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

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

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

 import org.kuali.student.common.ui.client.widgets.list.impl.KSRadioButtonListImpl;

 import org.kuali.student.common.ui.client.widgets.rules.AccessWidgetValue;

 import org.kuali.student.common.ui.client.widgets.search.KSPicker;

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

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

 import org.kuali.student.core.search.dto.SearchResultCell;

 import org.kuali.student.core.search.dto.SearchResultRow;

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

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

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

 public class GradeWidget extends Composite implements AccessWidgetValue, HasDataValue {

     protected static final String GRADE_TYPE_ID_CELL_KEY = "lrc.resultColumn.resultComponent.id";

     protected static final String GRADE_TYPE_NAME_CELL_KEY = "lrc.resultColumn.resultComponent.name";

     private FlowPanel layout = new FlowPanel();

     KSPicker gradeTypeWidget;

     KSPicker gradeWidget = null;

     Metadata gradeMetadata;

     private String initialGradeValue = null;

     public GradeWidget() {

         this.initWidget(layout);

     }

     @Override

     public void initWidget(List<Metadata> fieldsMetadata) {

         layout.clear();

         gradeTypeWidget = (KSPicker) DefaultWidgetFactory.getInstance().getWidget(fieldsMetadata.get(0));

         layout.add(gradeTypeWidget);

         gradeMetadata = fieldsMetadata.get(1);

         setupHandlers();

     }

     private void setupHandlers() {

         ((KSRadioButtonList)gradeTypeWidget.getInputWidget()).addSelectionChangeHandler(new SelectionChangeHandler() {

             @Override

             public void onSelectionChange(SelectionChangeEvent event) {

                 String gradeTypeSelected = ((KSRadioButtonListImpl)event.getWidget()).getSelectedItem();

                 gradeMetadata.getInitialLookup().getParams().get(0).setDefaultValueList(null);

                 gradeMetadata.getInitialLookup().getParams().get(0).setDefaultValueString(gradeTypeSelected);

                 addGradeListWidget(true, !event.isUserInitiated());

             }

         });

     }

     private void addGradeListWidget(boolean enabled, boolean addInitialValueCallback) {

         if (gradeWidget != null) {

             layout.remove(gradeWidget);

         }

         // this callback ensures the initial grade value is selected if it should be set

         // since the values are populated async, a widget ready callback must be used

         if(addInitialValueCallback) {

             ((KSSelectItemWidgetAbstract)gradeWidget.getInputWidget()).addWidgetReadyCallback(new Callback<Widget>() {

                 @Override

                 public void exec(Widget result) {

                     gradeWidget.setValue(initialGradeValue);

                     KSDropDownImpl theWidget = (KSDropDownImpl) result;

                     theWidget.selectItem(initialGradeValue);

                 }

             });

         }

         gradeWidget = (KSPicker) DefaultWidgetFactory.getInstance().getWidget(gradeMetadata);

         ((KSDropDown)gradeWidget.getInputWidget()).setEnabled(enabled);

         layout.add(gradeWidget);

     }

         @Override

         public void addValueChangeCallback(Callback<Data.Value> callback) {

         }

         @Override

         public void setValue(Data.Value value) {

             if(value != null && value.toString() != null) {

                 initialGradeValue = value.toString();

             }

         addGradeListWidget((initialGradeValue != null), false);

         gradeWidget.setValue(value);

                 // if setting an initial value that is not the blank default (i.e. populating the grade widget from a previously saved value)

                 if(initialGradeValue != null) {

                     // add a callback to select the grade type after the grade dropdown has been initialized

                 final String selectedGradeValue = value.toString();

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

                 @Override

                 public void exec(Widget widget) {

                     List<SearchResultRow> gradeItems = ((SearchResultListItems) ((KSSelectItemWidgetAbstract)gradeWidget.getInputWidget()).getListItems()).getReadOnlyResults();

                     // find the selected row for the grade

                     SearchResultRow selectedGradeRow = null;

                     String selectedGradeTypeId = null;

                     for(SearchResultRow row : gradeItems) {

                         for(SearchResultCell cell : row.getCells()) {

                             if(cell.getValue().equals(selectedGradeValue)) {

                                 selectedGradeRow = row;

                             }

                             // get the grade type id from any row  

                             // If the right row is found, this value will contain the grade type we are looking for

                             if(cell.getKey().equals(GRADE_TYPE_ID_CELL_KEY)) {

                                 selectedGradeTypeId = cell.getValue();

                             }

                         }

                         // once the grade row is found, break

                         if(selectedGradeRow != null) {

                             break;

                         }

                     }

                     // make sure to check for null, though it would indicate bad data if true

                     if(selectedGradeRow == null) {

                         return;

                     }

                     // now we can select the grade type in the grade type widget

                     ((KSSelectItemWidgetAbstract)gradeTypeWidget.getInputWidget()).selectItem(selectedGradeTypeId);

                 }

             };

                     ((KSSelectItemWidgetAbstract)gradeWidget.getInputWidget()).addWidgetReadyCallback(afterInitCallback);

                 }

         }

     @Override

     public void getValue(Callback<String> doneSaveCallback) { 

     }

     @Override

     public void setValue(String id) {

     }

     @Override

     public Data.Value getValue() {

         return (gradeWidget != null ? gradeWidget.getValue() : null);

     }

 }