// Copyright 2007, 2008 The Apache Software Foundation

 //

 // Licensed under the Apache 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.apache.org/licenses/LICENSE-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.apache.tapestry5.internal.util;

 import org.apache.tapestry5.*;

 import java.util.Map;

 public class SelectModelRenderer implements SelectModelVisitor

 {

     private final MarkupWriter writer;

     private final ValueEncoder encoder;

     public SelectModelRenderer(final MarkupWriter writer, ValueEncoder encoder)

     {

         this.writer = writer;

         this.encoder = encoder;

     }

     public void beginOptionGroup(OptionGroupModel groupModel)

     {

         writer.element("optgroup", "label", groupModel.getLabel());

         writeDisabled(groupModel.isDisabled());

         writeAttributes(groupModel.getAttributes());

     }

     public void endOptionGroup(OptionGroupModel groupModel)

     {

         writer.end(); // select

     }

     @SuppressWarnings("unchecked")

     public void option(OptionModel optionModel)

     {

         Object optionValue = optionModel.getValue();

         String clientValue = encoder.toClient(optionValue);

         writer.element("option", "value", clientValue);

         if (isOptionSelected(optionModel, clientValue)) writer.attributes("selected", "selected");

         writeDisabled(optionModel.isDisabled());

         writeAttributes(optionModel.getAttributes());

         writer.write(optionModel.getLabel());

         writer.end();

     }

     private void writeDisabled(boolean disabled)

     {

         if (disabled) writer.attributes("disabled", "disabled");

     }

     private void writeAttributes(Map<String, String> attributes)

     {

         if (attributes == null) return;

         for (Map.Entry<String, String> e : attributes.entrySet())

             writer.attributes(e.getKey(), e.getValue());

     }

     /**

      * If true, then the selected attribute will be written. This implementation always returns false.

      */

     protected boolean isOptionSelected(OptionModel optionModel, String clientValue)

     {

         return false;

     }

 }