/**
    * 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.KeyUpEvent;
  import com.google.gwt.event.dom.client.KeyUpHandler;
  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.event.logical.shared.ValueChangeHandler;
  import com.google.gwt.user.client.ui.Label;
  import com.google.gwt.user.client.ui.TextArea;
  
  /**
   * 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 KSTextArea extends TextArea implements HasWatermark {
      private boolean hasWatermark = false;
      private boolean watermarkShowing = false;
      private String watermarkText;
      private int left = 0;
      private int maxLength = 0;
  
      /**
       * Creates a new empty text area.
       */
      public KSTextArea() {
          super();
          setupDefaultStyle();
      }
  
      /**
       * Creates a new text area using the text area element specified.
       * 
       * @param element
       *            a <TextArea> element
       */
      public KSTextArea(Element element) {
          super(element);
          setupDefaultStyle();
      }
  
      public KSTextArea(final Label countLabel, final int maximumChar) {
          super();
          setupDefaultStyle();
          this.setMaxLength(maximumChar);
          setLabel(countLabel);
          this.addKeyUpHandler(new KeyUpHandler() {
  
              @Override
              public void onKeyUp(KeyUpEvent event) {
                  setLabel(countLabel);
              }
          });
  
          this.addValueChangeHandler(new ValueChangeHandler<String>() {
  
              @Override
              public void onValueChange(ValueChangeEvent<String> event) {
                  setLabel(countLabel);
              }
          });
  
      }
      
      public KSTextArea(final Label countLabel) {
          super();
          setupDefaultStyle();
          countLabel.setText(this.maxLength + " characters left");
          this.addKeyUpHandler(new KeyUpHandler() {
  
              @Override
              public void onKeyUp(KeyUpEvent event) {
                  setLabel(countLabel);
              }
          });
  
          this.addValueChangeHandler(new ValueChangeHandler<String>() {
  
              @Override
              public void onValueChange(ValueChangeEvent<String> event) {
                  setLabel(countLabel);
              }
         });
 
     }
 
     /**
      * This method sets the default style for the text area and text area events.
      */
     private void setupDefaultStyle() {
         addStyleName("KS-Textarea");
 
         this.addBlurHandler(new BlurHandler() {
             public void onBlur(BlurEvent event) {
                 KSTextArea.this.removeStyleName("KS-Textarea-Focus");
 
             }
         });
 
         this.addFocusHandler(new FocusHandler() {
             public void onFocus(FocusEvent event) {
                 KSTextArea.this.addStyleName("KS-Textarea-Focus");
 
             }
         });
 
         this.addMouseOverHandler(new MouseOverHandler() {
             public void onMouseOver(MouseOverEvent event) {
                 KSTextArea.this.addStyleName("KS-Textarea-Hover");
 
             }
         });
 
         this.addMouseOutHandler(new MouseOutHandler() {
 
             public void onMouseOut(MouseOutEvent event) {
                 KSTextArea.this.removeStyleName("KS-Textarea-Hover");
 
             }
 
         });
 
     }
 
     @Override
     public void setWatermarkText(String text) {
         if (!hasWatermark) {
             hasWatermark = true;
             watermarkText = text;
             if (getText() == null || getText().isEmpty()) {
                 addStyleName("watermark-text");
                 KSTextArea.super.setText(watermarkText);
                 watermarkShowing = true;
             }
 
             this.addFocusHandler(new FocusHandler() {
 
                 @Override
                 public void onFocus(FocusEvent event) {
                     if (watermarkShowing) {
                         removeStyleName("watermark-text");
                         KSTextArea.super.setText("");
                         watermarkShowing = false;
                     }
                 }
             });
 
             this.addBlurHandler(new BlurHandler() {
 
                 @Override
                 public void onBlur(BlurEvent event) {
                     if (getText() == null || getText().isEmpty()) {
                         addStyleName("watermark-text");
                         KSTextArea.super.setText(watermarkText);
                         watermarkShowing = true;
                     }
                 }
             });
         } else {
             watermarkText = text;
             if (getText() == null || getText().isEmpty()) {
                 addStyleName("watermark-text");
                 KSTextArea.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);
     }
 
     public void setLabel(final Label countLabel) {
         left = this.maxLength - KSTextArea.this.getText().length();
         if (KSTextArea.this.getText().length() > this.maxLength) {
             countLabel.setText("Please remove " + left * -1 + " characters");
         } else {
             countLabel.setText(left + " characters left");
         }
         if ((left <= (this.maxLength * 0.1)) || (left <= 10)) {
             countLabel.getElement().setAttribute("style", "color: red;");
         } else {
             countLabel.getElement().removeAttribute("style");
         }
     }
 
     public void setMaxLength(int maxLength) {
         this.maxLength = maxLength;
     }
 
     public int getMaxLength() {
         return this.maxLength;
     }
     
 }