/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.myfaces.event;
  
  import javax.el.ELContext;
  import javax.el.ValueExpression;
  import javax.faces.component.StateHolder;
  import javax.faces.context.FacesContext;
  import javax.faces.event.AbortProcessingException;
  import javax.faces.event.ActionEvent;
  import javax.faces.event.ActionListener;
  
  /**
   * The MyFaces implementation of the <code>SetPropertyActionListener</code>.
   * 
   * @author Dennis Byrne
   * @since 1.2
   */
  public class SetPropertyActionListener implements ActionListener, StateHolder
  {
  
      private ValueExpression target;
      
      private ValueExpression value;
      
      private boolean _transient ;
      
      public SetPropertyActionListener(){}
      
      public SetPropertyActionListener(ValueExpression target, ValueExpression value)
      {
          this.target = target;
          this.value = value;
      }
      
      public void processAction(ActionEvent actionEvent) throws AbortProcessingException
      {
          
          if( target == null )
          {
              throw new AbortProcessingException("@target has not been set");
          }
  
          if( value == null )
          {
              throw new AbortProcessingException("@value has not been set");
          }
          
          FacesContext ctx = FacesContext.getCurrentInstance();
          
          if( ctx == null )
          {
              throw new AbortProcessingException("FacesContext ctx is null");
          }
          
          ELContext ectx = ctx.getELContext();
          
          if( ectx == null )
          {
              throw new AbortProcessingException("ELContext ectx is null");
          }
          
          // TODO use a Converter before calling setValue 
          
          target.setValue(ectx, value.getValue(ectx));
          
      }
  
      public Object saveState(FacesContext context)
      {
          Object[] state = new Object[2];
          state[0] = target;
          state[1] = value;
          return state;
      }
  
      public void restoreState(FacesContext context, Object state)
      {
          Object[] values = (Object[]) state;
          target = (ValueExpression) values[0];
          value = (ValueExpression) values[1];
      }
  
     public boolean isTransient()
     {
         return _transient;
     }
 
     public void setTransient(boolean trans)
     {
         this._transient = trans;
     }
 
     public ValueExpression getTarget()
     {
         return target;
     }
 
     public void setTarget(ValueExpression target)
     {
         this.target = target;
     }
 
     public ValueExpression getValue()
     {
         return value;
     }
 
     public void setValue(ValueExpression value)
     {
         this.value = value;
     }
 
 }