/**
    * 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.widgets;
  
  import com.google.gwt.dom.client.Element;
  import com.google.gwt.event.dom.client.BlurEvent;
  import com.google.gwt.event.dom.client.BlurHandler;
  import com.google.gwt.event.dom.client.FocusEvent;
  import com.google.gwt.event.dom.client.FocusHandler;
  import com.google.gwt.event.dom.client.MouseOutEvent;
  import com.google.gwt.event.dom.client.MouseOutHandler;
  import com.google.gwt.event.dom.client.MouseOverEvent;
  import com.google.gwt.event.dom.client.MouseOverHandler;
  import com.google.gwt.event.logical.shared.ValueChangeEvent;
  import com.google.gwt.user.client.ui.TextBox;
  
  /**
   * KSTextArea wraps gwt TextArea.  This class provides most of the same functionality, but sets KS css styles
   * for its default look and a variety of TextArea events (for improved browser compatibility and customizability).
   *
   * @author Kuali Student Team
   *
   *
   */
  public class KSTextBox extends TextBox implements HasWatermark{
  	private boolean hasWatermark = false;
  	private boolean watermarkShowing = false;
  	private String watermarkText;
  	
      /**
       * Creates an empty text box.
       *
       */
      public KSTextBox() {
          super();
          setupDefaultStyle();
      }
  
      /**
       *  Creates a new text box using the text box element specified.
       *
       * @param element a <input> element of type 'text'
       */
      public KSTextBox(Element element) {
          super(element);
          setupDefaultStyle();
      }
  
      /**
       * This method sets the default style for the text box and text box events.
       *
       */
      private void setupDefaultStyle() {
          addStyleName("KS-Textbox");
  
          this.addBlurHandler(new BlurHandler(){
              public void onBlur(BlurEvent event) {
                  KSTextBox.this.removeStyleName("KS-Textbox-Focus");
  
              }
          });
  
          this.addFocusHandler(new FocusHandler(){
              public void onFocus(FocusEvent event) {
                  KSTextBox.this.addStyleName("KS-Textbox-Focus");
  
              }
          });
  
          this.addMouseOverHandler(new MouseOverHandler(){
              public void onMouseOver(MouseOverEvent event) {
                  KSTextBox.this.addStyleName("KS-Textbox-Hover");
  
              }
          });
  
          this.addMouseOutHandler(new MouseOutHandler(){
  
              public void onMouseOut(MouseOutEvent event) {
                  KSTextBox.this.removeStyleName("KS-Textbox-Hover");
  
              }
  
          });
  
      }
 
 	@Override
 	public void setWatermarkText(String text) {
 		if(!hasWatermark){
 			hasWatermark = true;
 			watermarkText = text;
 			if(getText() == null || getText().isEmpty()){
 				addStyleName("watermark-text");
 				super.setText(watermarkText);
 				watermarkShowing = true;
 			}
 			
 			this.addFocusHandler(new FocusHandler(){
 	
 				@Override
 				public void onFocus(FocusEvent event) {
 					if(watermarkShowing){
 						removeStyleName("watermark-text");
 						KSTextBox.super.setText("");
 						watermarkShowing = false;
 					}
 				}
 			});
 			
 			this.addBlurHandler(new BlurHandler(){
 	
 				@Override
 				public void onBlur(BlurEvent event) {
 					if(getText() == null || getText().isEmpty()){
 						addStyleName("watermark-text");
 						KSTextBox.super.setText(watermarkText);
 						watermarkShowing = true;
 					}
 				}
 			});
 		}
 		else{
 			watermarkText = text;
 			if(getText() == null || getText().isEmpty()){
 				addStyleName("watermark-text");
 				KSTextBox.super.setText(watermarkText);
 				watermarkShowing = true;
 			}
 		}
 	}
 	
 	@Override
 	public boolean hasWatermark(){
 		return hasWatermark;
 	}
 	
 	@Override
 	public boolean watermarkShowing() {
 		return watermarkShowing;
 	}
 	
 	@Override
 	public String getText() {
 		if(!watermarkShowing){
 			return super.getText();
 		}
 		return null;
 	}
 	
 	@Override
 	public String getValue() {
 		if(!watermarkShowing){
 			return super.getValue();
 		}
 		return null;
 	}
 	
 	@Override
 	public void setValue(String value) {
 		if(hasWatermark){
 			if(value == null || (value != null && value.isEmpty())){
 				super.setValue(watermarkText);
 				addStyleName("watermark-text");
 				watermarkShowing = true;
 			}
 			else{
 				super.setValue(value);
 				removeStyleName("watermark-text");
 				watermarkShowing = false;
 			}
 		}
 		else{
 			super.setValue(value);
 		}
 	}
 	
 	@Override
 	public void setText(String text) {
 	    String oldValue = super.getText();
 	    if(hasWatermark){
 			if(text == null || (text != null && text.isEmpty())){
 				super.setText(watermarkText);
 				addStyleName("watermark-text");
 				watermarkShowing = true;
 			}
 			else{
 				super.setText(text);
 				removeStyleName("watermark-text");
                 watermarkShowing = false;
 			}
 		}
 		else{
 			super.setText(text);
 		}
 	    ValueChangeEvent.fireIfNotEqual(this, oldValue, text);
 
 	}
 }