/**
    * 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;
  
  import com.google.gwt.core.client.GWT;
  import com.google.gwt.event.dom.client.BlurEvent;
  import com.google.gwt.event.dom.client.BlurHandler;
  import com.google.gwt.event.dom.client.HasBlurHandlers;
  import com.google.gwt.user.client.ui.Widget;
  import org.kuali.student.common.ui.client.configurable.mvc.multiplicity.MultiplicityGroup;
  import org.kuali.student.common.ui.client.mvc.Callback;
  import org.kuali.student.common.ui.client.mvc.HasFocusLostCallbacks;
  import org.kuali.student.common.ui.client.widgets.KSLabel;
  import org.kuali.student.common.ui.client.widgets.list.HasSelectionChangeHandlers;
  import org.kuali.student.common.ui.client.widgets.list.KSCheckBoxList;
  import org.kuali.student.common.ui.client.widgets.list.KSSelectedList;
  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.search.KSPicker;
  
  /**
   * Adds the appropriate handler to the widget contained within the FieldDescriptor for when
   * to set that the field has had focus/user interaction based on what type of widget
   *
   * @author Kuali Student Team
   */
  public class ValidationEventBindingImpl implements ValidationEventBinding {
  
      public void bind(final FieldDescriptor fd) {
          Widget w = fd.getFieldWidget();
  
          if (w instanceof HasSelectionChangeHandlers) {
              ((HasSelectionChangeHandlers) w).addSelectionChangeHandler(new SelectionChangeHandler() {
                  @Override
                  public void onSelectionChange(SelectionChangeEvent event) {
                      if (event.isUserInitiated()) {
                          processValidationEvent(fd);
                      }
                  }
              });
          } else if(w instanceof KSPicker && ((KSPicker)w).getInputWidget() instanceof HasSelectionChangeHandlers){
              ((KSPicker)w).addSelectionChangeHandler(new SelectionChangeHandler() {
                  @Override
                  public void onSelectionChange(SelectionChangeEvent event) {
                  	if(event.isUserInitiated()){
                  		processValidationEvent(fd);
                  	}
                  }
              });
          } else if (w instanceof HasBlurHandlers) {
              ((HasBlurHandlers) w).addBlurHandler(new BlurHandler() {
                  public void onBlur(BlurEvent event) {
                      processValidationEvent(fd);
                  }
              });
          } else if (w instanceof HasFocusLostCallbacks) {
              ((HasFocusLostCallbacks) w).addFocusLostCallback(new Callback<Boolean>() {
                  @Override
                  public void exec(Boolean result) {
                      processValidationEvent(fd);
                  }
              });
          } else if (w instanceof KSLabel
                  || w instanceof org.kuali.student.common.ui.client.configurable.mvc.multiplicity.MultiplicityComposite
                  || w instanceof MultiplicityGroup) {
              //Do nothing these are valid but do not fire validation events (maybe?)
          } else {
              GWT.log("The field with key: " + fd.getFieldKey() +
                      " does not use a widget which implements an interface that can perform on the fly validation", null);
          }
          //Dont add focus lost to the oracle if it is repeating
          if (w instanceof KSSelectedList && !((KSSelectedList)w).getConfig().isRepeating) {
              ((HasFocusLostCallbacks) w).addFocusLostCallback(new Callback<Boolean>() {
                  @Override
                  public void exec(Boolean result) {
                      processValidationEvent(fd);
                  }
              });
          }
  
      }
  
      private void processValidationEvent(FieldDescriptor fieldDescriptor) {
          fieldDescriptor.setHasHadFocus(true);
          fieldDescriptor.getValidationRequestCallback().exec(true);
      }
 }