/**
    * Copyright 2005-2015 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.opensource.org/licenses/ecl2.php
    *
   * 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.rice.krad.uif.element;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.krad.datadictionary.parse.BeanTag;
  import org.kuali.rice.krad.datadictionary.parse.BeanTagAttribute;
  import org.kuali.rice.krad.datadictionary.parse.BeanTags;
  import org.kuali.rice.krad.datadictionary.validator.ValidationTrace;
  import org.kuali.rice.krad.datadictionary.validator.Validator;
  import org.kuali.rice.krad.uif.component.Component;
  import org.kuali.rice.krad.uif.util.ComponentFactory;
  import org.kuali.rice.krad.uif.util.LifecycleElement;
  
  /**
   * Content element that renders a HTML <code>&lt;IMG&gt;</code> tag
   *
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  @BeanTag(name = "image", parent = "Uif-Image")
  public class Image extends ContentElementBase {
      private static final long serialVersionUID = -3911849875276940507L;
  
      private String source;
      private String altText;
      private String height;
      private String width;
  
      private boolean captionHeaderPlacementAboveImage;
  
      private String captionHeaderText;
      private Header captionHeader;
  
      private String cutlineText;
      private Message cutlineMessage;
  
      public Image() {
          super();
  
          altText = "";
      }
  
      /**
       * The following initialization is performed:
       *
       * <ul>
       * <li>Initializes the cutline message and caption header components if necessary</li>
       * </ul>
       *
       * {@inheritDoc}
       */
      @Override
      public void performInitialization(Object model) {
          super.performInitialization(model);
  
          if ((StringUtils.isNotBlank(captionHeaderText) || (getPropertyExpression("captionHeaderText") != null)) && (
                  captionHeader == null)) {
              captionHeader = ComponentFactory.getImageCaptionHeader();
          }
  
          if ((StringUtils.isNotBlank(cutlineText) || (getPropertyExpression("cutlineText") != null)) && (cutlineMessage
                  == null)) {
              cutlineMessage = ComponentFactory.getImageCutlineMessage();
          }
      }
  
      /**
       * Performs the following steps
       *
       * <ul>
       * <li>Set the caption header text on the caption header</li>
       * <li>Set the cutline text on the cutline message</li>
       * </ul>
       *
       * {@inheritDoc}
       */
      @Override
      public void performApplyModel(Object model, LifecycleElement parent) {
          super.performApplyModel(model, parent);
  
          if (StringUtils.isNotBlank(captionHeaderText)) {
              captionHeader.setHeaderText(captionHeaderText);
          }
  
          if (StringUtils.isNotBlank(cutlineText)) {
              cutlineMessage.setMessageText(cutlineText);
         }
     }
 
     /**
      * returns the URL of this image
      *
      * @return the URL of this image.
      */
     @BeanTagAttribute
     public String getSource() {
         return this.source;
     }
 
     /**
      * Sets the URL of this image
      *
      * @param source the URL of this image
      */
     public void setSource(String source) {
         this.source = source;
     }
 
     /**
      * Provides alternate information for the image element
      *
      * <p>The altText property specifies an alternate text for an image. It is displayed by the browser
      * if the image cannot be displayed.  This is especially important for accessibility, because screen
      * readers can't understand images, but rather will read aloud the alternative text assigned to them.
      * <br>
      * Some best practices:
      * <ul>
      * <li>spacer images, bullets, and icons should have the altText set to null or the empty string. This
      * will prevent screen readers from announcing it.</li>
      * <li>Make the altText message as short and succinct as possible</li>
      * <li>Describe the content of the image and nothing more</li>
      * </ul>
      * </p>
      *
      * @return alternative information about this image
      */
     @BeanTagAttribute
     public String getAltText() {
         return this.altText;
     }
 
     /**
      * Sets the alternate text property for this image
      *
      * @param altText the alternative information about the image
      */
     public void setAltText(String altText) {
         this.altText = altText;
     }
 
     /**
      * Returns the height style attribute of this image
      *
      * <p>
      * The default unit of measure is pixels.<br>
      * It is good practice to specify both the height and width attributes for an image.
      * If these attributes are set, the space required for the image is reserved when the page is loaded.
      * However, without these attributes, the browser does not know the size of the image. The effect will
      * be that the page layout will change while the images load.
      * </p>
      *
      * @return the height style attribute of this image
      */
     @BeanTagAttribute
     public String getHeight() {
         return this.height;
     }
 
     /**
      * Sets the height style attribute of the image.
      *
      * @param height the height of the image
      */
     public void setHeight(String height) {
         this.height = height;
     }
 
     /**
      * Returns the width style attribute of the image
      *
      * <p>
      * The default unit of measure is pixels.<br>
      * It is good practice to specify both the height and width attributes for an image.
      * If these attributes are set, the space required for the image is reserved when the page is loaded.
      * However, without these attributes, the browser does not know the size of the image. The effect will
      * be that the page layout will change while the images load.
      * <p>
      *
      * @return the width of this image
      */
     @BeanTagAttribute
     public String getWidth() {
         return width;
     }
 
     /**
      * Sets the width style attribute of the image
      *
      * @param width the width of this image
      */
     public void setWidth(String width) {
         this.width = width;
     }
 
     /**
      * Retrieves the caption text for this image
      *
      * <p>
      * The caption text is a headline for the picture. It may be displayed either above or below the picture.
      * </p>
      *
      * @return the caption
      */
     @BeanTagAttribute
     public String getCaptionHeaderText() {
         return captionHeaderText;
     }
 
     /**
      * Sets the text displayed as of the caption for the picture
      *
      * @param captionHeaderText the caption text
      */
     public void setCaptionHeaderText(String captionHeaderText) {
         this.captionHeaderText = captionHeaderText;
     }
 
     /**
      * Retrieves the {@link Header} component used to display the caption for this image
      *
      * @return Header component which wraps the caption text.
      */
     @BeanTagAttribute
     public Header getCaptionHeader() {
         return captionHeader;
     }
 
     /**
      * Sets the Header used to display the caption for this image
      *
      * @param captionHeader header component which wraps the caption text
      */
     public void setCaptionHeader(Header captionHeader) {
         this.captionHeader = captionHeader;
     }
 
     /**
      * Retrieves the cutline text for this image
      *
      * <p>
      * The cutline text give more detailed information about the picture. Generally it describes
      * the who, what, where, when of this image.
      * </p>
      *
      * @return the cutline text.
      */
     @BeanTagAttribute
     public String getCutlineText() {
         return cutlineText;
     }
 
     /**
      * Sets the cutline text that describes this image
      *
      * @param cutlineText the cutline text that describes this image
      */
     public void setCutlineText(String cutlineText) {
         this.cutlineText = cutlineText;
     }
 
     /**
      * Gets the {@link Message} component used to display the cutline.
      *
      * <p>
      * Wrapping the cutline text with a Message component allows styling of the cutline text.
      * </p>
      *
      * @return Message component wrapping the cutline
      */
     @BeanTagAttribute
     public Message getCutlineMessage() {
         return cutlineMessage;
     }
 
     /**
      * Sets the Message component used to display the cutline for this image
      *
      * @param cutlineMessage Message
      */
     public void setCutlineMessage(Message cutlineMessage) {
         this.cutlineMessage = cutlineMessage;
     }
 
     /**
      * Specifies whether the image caption is to be displayed above or below the image
      *
      * @return true if the caption is to be displayed above the image. false if displayed below the image.
      */
     @BeanTagAttribute
     public boolean isCaptionHeaderPlacementAboveImage() {
         return captionHeaderPlacementAboveImage;
     }
 
     /**
      * Sets whether the image caption is to be displayed above or below the image
      *
      * @param captionHeaderPlacementAboveImage true displays above image, false displays below image
      */
     public void setCaptionHeaderPlacementAboveImage(boolean captionHeaderPlacementAboveImage) {
         this.captionHeaderPlacementAboveImage = captionHeaderPlacementAboveImage;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void completeValidation(ValidationTrace tracer){
         tracer.addBean(this);
 
         // Checks that a source is set
         if(getSource()==null){
             if(!Validator.checkExpressions(this, "source")){
                 String currentValues [] = {"source ="+getSource()};
                 tracer.createError("Source must be set",currentValues);
             }
         }
 
         // Checks that alt text is set
         if(getAltText().compareTo("")==0){
             if(Validator.checkExpressions(this, "altText")){
                 String currentValues [] = {"altText ="+getAltText()};
                 tracer.createWarning("Alt text should be set, violates accessibility standards if not set",currentValues);
             }
         }
 
         super.completeValidation(tracer.getCopy());
     }
 }