/*

  * Copyright 2004 Chris Nelson

  *

  * 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.trails.component;

 import java.util.List;

 import ognl.Ognl;

 import org.apache.commons.lang.StringUtils;

 import org.trails.TrailsRuntimeException;

 public class IdentifierSelectionModel extends AbstractPropertySelectionModel

 {

         private String idProperty = "id";

         public IdentifierSelectionModel(List instances, String idProperty)

         {

                 super(instances);

                 this.idProperty = idProperty;

         }

         public IdentifierSelectionModel(List instances, String idProperty, boolean allowNone)

         {

                 super(instances, allowNone);

                 this.idProperty = idProperty;

         }

         /* (non-Javadoc)

                  * @see org.apache.tapestry.form.IPropertySelectionModel#getValue(int)

                  */

         public String getValue(int index)

         {

                 try

                 {

                         if (allowNone && index == 0)

                         {

                                 return DEFAULT_NONE_VALUE;

                         } else

                         {

                                 return Ognl.getValue(idProperty,instances.get(index)).toString();

                         }

                 } catch (Exception e)

                 {

                         throw new TrailsRuntimeException(e);

                 }

         }

         /* (non-Javadoc)

                  * @see org.apache.tapestry.form.IPropertySelectionModel#translateValue(java.lang.String)

                  */

         public Object translateValue(String value)

         {

                 if (StringUtils.isEmpty(value)) return null;

                 List realInstances = allowNone ? instances.subList(1, instances.size()) : instances;

                 try

                 {

                         if (allowNone)

                         {

                                 if (value.equals(DEFAULT_NONE_VALUE)) return null;

                         }

                         List matches = (List) Ognl.getValue(

                                 "#root.{? #this." + idProperty + ".toString() == \"" + value + "\" }",

                                 realInstances);

                         if (matches.size() > 0) return matches.get(0);

                         return null;

                 } catch (Exception e)

                 {

                         throw new TrailsRuntimeException(e);

                 }

         }

         public boolean isDisabled(int i)

         {

                 return false; 

         }

 }