/**

  * 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.configurable.mvc.sections.VerticalSection;

 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.KSLabel;

 import org.kuali.student.common.ui.client.widgets.field.layout.element.MessageKeyInfo;

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

 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.SimpleListItems;

 import org.kuali.student.common.ui.client.widgets.progress.BlockingTask;

 import org.kuali.student.common.ui.client.widgets.progress.KSBlockingProgressIndicator;

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

 public class CourseWidget extends Composite implements AccessWidgetValue, HasDataValue {

     private CluSetRetriever courseMetadataRetriever  = new CluSetRetrieverImpl();

     private Callback getCluNameCallback;

     //widgets

     private VerticalSection layout = new VerticalSection();

     private KSDropDown courseTypeWidget;

     private KSPicker courseWidget = null;

     private KSLabel previousCourseCode;

     private String previousCourseId;

     //data

     private Metadata searchCourseMetadata = null;

     private BlockingTask initializeTask = new BlockingTask("Initializing");

     public CourseWidget() {

         this.initWidget(layout);

     }

     @Override

     public void initWidget(List<Metadata> fieldsMetadata) {

         previousCourseCode = null;

         previousCourseId = null;

         layout.clear();

         final VerticalSection choosingSection = new VerticalSection();

         choosingSection.addWidget(new KSLabel("<b>Add a course</b>"));

         //first metadata is a drop down to select type of course

         createAndAddCourseTypesDropdown();

         retrieveMetadata();

     }

     private void createAndAddCourseTypesDropdown() {

         courseTypeWidget = new KSDropDown();

         SimpleListItems courseTypes = new SimpleListItems();

         courseTypes.addItem(CommonWidgetConstants.CLU_SET_APPROVED_CLUS_FIELD, "Approved Courses");

         courseTypes.addItem(CommonWidgetConstants.CLU_SET_PROPOSED_CLUS_FIELD, "Proposed Courses");

         courseTypeWidget.setListItems(courseTypes);

         courseTypeWidget.addSelectionChangeHandler(new SelectionChangeHandler() {

             @Override

             public void onSelectionChange(SelectionChangeEvent event) {

                 String courseTypeSelected = ((KSDropDownImpl)event.getWidget()).getSelectedItem();

                 if (courseTypeSelected == null) {

                     if (courseWidget != null) {

                         layout.remove(courseWidget);

                     }                    

                     return;

                 }

                 addCourseListWidget(true, courseTypeSelected);

             }

         });        

         layout.add(courseTypeWidget);

     }

     private void retrieveMetadata() {

         if (searchCourseMetadata == null) {

             KSBlockingProgressIndicator.addTask(initializeTask);

             courseMetadataRetriever.getMetadata("courseSet", new Callback<Metadata>(){

                 @Override

                 public void exec(Metadata result) {

                     searchCourseMetadata = result;

                     searchCourseMetadata.getProperties().get(CommonWidgetConstants.CLU_SET_APPROVED_CLUS_FIELD).getConstraints().get(0).setMaxOccurs(1);

                     searchCourseMetadata.getProperties().get(CommonWidgetConstants.CLU_SET_PROPOSED_CLUS_FIELD).getConstraints().get(0).setMaxOccurs(1);

                     searchCourseMetadata.getProperties().get(CommonWidgetConstants.CLU_SET_APPROVED_CLUS_FIELD).getConstraints().get(0).setId("single");

                     searchCourseMetadata.getProperties().get(CommonWidgetConstants.CLU_SET_PROPOSED_CLUS_FIELD).getConstraints().get(0).setId("single");

                     KSBlockingProgressIndicator.removeTask(initializeTask);

                     if (previousCourseCode == null) {

                         courseTypeWidget.selectItem(CommonWidgetConstants.CLU_SET_APPROVED_CLUS_FIELD);

                         addCourseListWidget(true, courseTypeWidget.getSelectedItem());

                     }

                 }

             });

         } else {

             if (previousCourseCode == null) {

                 courseTypeWidget.selectItem(CommonWidgetConstants.CLU_SET_APPROVED_CLUS_FIELD);

                 addCourseListWidget(true, courseTypeWidget.getSelectedItem());

             }

         }

     }

     private void addCourseListWidget(boolean enabled, String courseType) {

         if (courseWidget != null) {

             layout.remove(courseWidget);

         }

         if (previousCourseCode != null) {

             layout.remove(previousCourseCode);

             previousCourseCode = null;

             previousCourseId = null;

         }

         courseWidget = (KSPicker) DefaultWidgetFactory.getInstance().getWidget(searchCourseMetadata.getProperties().get(courseType));

         courseWidget.getSearchPanel().setMutipleSelect(false);

     //    ((KSSuggestBox) courseWidget.getInputWidget()).setEnabled(enabled);

         layout.add(courseWidget);

     }

     protected MessageKeyInfo generateMessageInfo(String labelKey) {

         return new MessageKeyInfo("clusetmanagement", "clusetmanagement", "draft", labelKey);

     }

         @Override

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

         }

         @Override

         public void setValue(Data.Value value) {    

         }

     @Override

     public void getValue(Callback<String> doneSaveCallback) { 

     }

     @Override

     public void setValue(final String id) {

         if (id != null) {

             getCluNameCallback.exec(id);

         }        

     }

     public void setLabelContent(String id, final String code) {

         layout.clear();

         previousCourseId = id;

         previousCourseCode = new KSLabel(code);

         layout.add(previousCourseCode);

         createAndAddCourseTypesDropdown();

     }

     public void addGetCluNameCallback(Callback callback) {

         this.getCluNameCallback = callback;    

     }

     @Override

     public Data.Value getValue() {

         Data.Value pickerValue = courseWidget.getValue();

         if ((pickerValue.toString().isEmpty()) && (previousCourseCode != null) && (!previousCourseCode.getText().isEmpty())) {

             return new Data.StringValue(previousCourseId);

         }

         return pickerValue;

     }

 }