/**
    * Copyright 2005-2012 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.validator.ErrorReport;
  import org.kuali.rice.krad.datadictionary.validator.RDValidator;
  import org.kuali.rice.krad.datadictionary.validator.TracerToken;
  import org.kuali.rice.krad.uif.component.Component;
  import org.kuali.rice.krad.uif.util.ComponentFactory;
  import org.kuali.rice.krad.uif.view.View;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Content element that renders a HTML <code>&lt;IMG&gt;</code> tag
   *
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  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>
       *
       * @see org.kuali.rice.krad.uif.component.ComponentBase#performInitialization(org.kuali.rice.krad.uif.view.View,
       *      java.lang.Object)
       */
      @Override
      public void performInitialization(View view, Object model) {
          super.performInitialization(view, model);
  
          if ((StringUtils.isNotBlank(captionHeaderText) || (getPropertyExpression("captionHeaderText") != null)) && (
                  captionHeader == null)) {
              captionHeader = ComponentFactory.getImageCaptionHeader();
              view.assignComponentIds(captionHeader);
          }
  
          if ((StringUtils.isNotBlank(cutlineText) || (getPropertyExpression("cutlineText") != null)) && (cutlineMessage
                  == null)) {
              cutlineMessage = ComponentFactory.getImageCutlineMessage();
              view.assignComponentIds(cutlineMessage);
          }
      }
  
      /**
       * Performs the final lifecycle phase for this element.
       *
       * <p>
       * 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>
       * </p>
       *
       * @see Component#performFinalize(org.kuali.rice.krad.uif.view.View, java.lang.Object, org.kuali.rice.krad.uif.component.Component)
       */
      @Override
      public void performFinalize(View view, Object model, Component parent) {
          super.performFinalize(view, model, parent);
  
         if (StringUtils.isNotBlank(captionHeaderText)) {
             captionHeader.setHeaderText(captionHeaderText);
         }
 
         if (StringUtils.isNotBlank(cutlineText)) {
             cutlineMessage.setMessageText(cutlineText);
         }
     }
 
     /**
      * @see org.kuali.rice.krad.uif.component.ComponentBase#getComponentsForLifecycle()
      */
     @Override
     public List<Component> getComponentsForLifecycle() {
         List<Component> components = super.getComponentsForLifecycle();
 
         components.add(captionHeader);
         components.add(cutlineMessage);
 
         return components;
     }
 
     /**
      * returns the URL of this image
      *
      * @return String containing the URL of this image.
      */
     public String getSource() {
         return this.source;
     }
 
     /**
      * Sets the URL of this image
      *
      * @param source - String representing 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 a String representing alternative information about this image
      */
     public String getAltText() {
         return this.altText;
     }
 
     /**
      * Sets the alternate text property for this image
      *
      * @param altText - a String containing 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 String containing of the height style attribute of this image
      */
     public String getHeight() {
         return this.height;
     }
 
     /**
      * Sets the height style attribute of the image.
      *
      * @param height - String containing 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 String containing the width of this image
      */
     public String getWidth() {
         return width;
     }
 
     /**
      * Sets the width style attribute of the image
      *
      * @param width - a String containing 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 String containing the caption
      */
     public String getCaptionHeaderText() {
         return captionHeaderText;
     }
 
     /**
      * Sets the text displayed as of the caption for the picture
      *
      * @param captionHeaderText - String containing 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.
      */
     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 String containing the cutline text.
      */
     public String getCutlineText() {
         return cutlineText;
     }
 
     /**
      * Sets the cutline text that describes this image
      *
      * @param cutlineText - String describing 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.
      */
     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.
      */
     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;
     }
 
     /**
      * @see org.kuali.rice.krad.uif.component.Component#completeValidation
      */
     @Override
     public ArrayList<ErrorReport> completeValidation(TracerToken tracer){
         ArrayList<ErrorReport> reports=new ArrayList<ErrorReport>();
         tracer.addBean(this);
 
         // Checks that a source is set
         if(getSource()==null){
             if(!RDValidator.checkExpressions(this,"source")){
                 ErrorReport error = ErrorReport.createError("Source must be set",tracer);
                 error.addCurrentValue("source ="+getSource());
                 reports.add(error);
             }
         }
 
         // Checks that alt text is set
         if(getAltText().compareTo("")==0){
             if(RDValidator.checkExpressions(this,"altText")){
                 ErrorReport error = ErrorReport.createWarning("Alt text should be set, violates accessibility standards if not set",tracer);
                 error.addCurrentValue("altText ="+getAltText());
                 reports.add(error);
             }
         }
 
         reports.addAll(super.completeValidation(tracer.getCopy()));
 
         return reports;
     }
 }