/*
    * Copyright 2008 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.ole.sys.document.web.renderers;
  
  import java.io.IOException;
  
  import javax.servlet.jsp.JspException;
  import javax.servlet.jsp.JspWriter;
  import javax.servlet.jsp.PageContext;
  import javax.servlet.jsp.tagext.Tag;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.ole.sys.document.web.util.RendererUtil;
  import org.kuali.rice.core.api.util.KeyValue;
  
  /**
   * This renders a drop down field to JSP
   */
  public class DropDownRenderer extends FieldRendererBase {
  
      /**
       * 
       * @see org.kuali.ole.sys.document.web.renderers.Renderer#render(javax.servlet.jsp.PageContext, javax.servlet.jsp.tagext.Tag)
       */
      public void render(PageContext pageContext, Tag parentTag) throws JspException {
          JspWriter out = pageContext.getOut();
          
          try {
              out.write(buildSelectControl());
              renderQuickFinderIfNecessary(pageContext, parentTag);
              if (isShowError()) {
                  renderErrorIcon(pageContext);
              }
              RendererUtil.registerEditableProperty(pageContext, getFieldName());
          }
          catch (IOException ioe) {
              throw new JspException("Difficulty rendering drop down control", ioe);
          }
      }
  
      /**
       * Builds a drop down control, based on the field
       * @param propertyPrefix the prefix of the property from the form to the business object
       * @return a String containing the HTML for the drop down control/select box
       */
      protected String buildSelectControl() {
          StringBuilder selectControl = new StringBuilder();
          selectControl.append("<select");
          
          selectControl.append(" id=\"");
          selectControl.append(getFieldName());
          selectControl.append("\" ");
          
          selectControl.append(" name=\"");
          selectControl.append(getFieldName());
          selectControl.append("\" ");
          
          selectControl.append(" title=\"");
          selectControl.append(this.getAccessibleTitle());
          selectControl.append("\"");
          
          final String onBlur = buildOnBlur();
          if (!StringUtils.isBlank(onBlur)) {
              selectControl.append(" onblur=\"");
              selectControl.append(onBlur);
              selectControl.append("\"");
          }
          
          selectControl.append(">");
          
          selectControl.append(buildOptions());
          
          selectControl.append("</select>");
          
          return selectControl.toString();
      }
      
      /**
       * Builds the options for the select box, given the valid values in the field
       * @return a String containing all the option tags for this drop down control
       */
      protected String buildOptions() {
          StringBuilder options = new StringBuilder();
          
          for (Object keyLabelPairAsObj : getField().getFieldValidValues()) {
              options.append(buildOption((KeyValue)keyLabelPairAsObj));
         }
         
         return options.toString();
     }
     
     /**
      * Builds an option tag for the given key label pair
      * @param keyLabelPair the key label pair to create an option tag from
      * @return the String with the option tag in it
      */
     protected String buildOption(KeyValue keyLabelPair) {
         StringBuilder option = new StringBuilder();
         
         option.append("<option value=\"");
         option.append(keyLabelPair.getKey());
         option.append("\"");
         if (getField().getPropertyValue().equalsIgnoreCase(keyLabelPair.getKey().toString())) {
             option.append(" selected=\"selected\"");
         }
         option.append(">");
         
         option.append(keyLabelPair.getValue());
         
         option.append("</options>");
         
         return option.toString();
     }
 
     /**
      * No quickfinder for us, thanks
      * @see org.kuali.ole.sys.document.web.renderers.FieldRenderer#renderQuickfinder()
      */
     public boolean renderQuickfinder() {
         return false;
     }
     
 }