/*
    * 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.view.facelets.el;
  
  import java.io.Externalizable;
  import java.io.IOException;
  import java.io.ObjectInput;
  import java.io.ObjectOutput;
  
  import javax.el.ELContext;
  import javax.el.ELException;
  import javax.el.PropertyNotFoundException;
  import javax.el.PropertyNotWritableException;
  import javax.el.ValueExpression;
  import javax.el.ValueReference;
  import javax.faces.FacesWrapper;
  import javax.faces.view.Location;
  import javax.faces.view.facelets.TagAttribute;
  
  /**
   * 
   * 
   * @author Jacob Hookom
   * @version $Id$
   */
  public class ContextAwareTagValueExpression
          extends ValueExpression
          implements Externalizable, FacesWrapper<ValueExpression>, ContextAware
  {
  
      private static final long serialVersionUID = 1L;
  
      private ValueExpression _wrapped; 
      private Location _location;
      private String _qName;
  
      public ContextAwareTagValueExpression()
      {
          super();
      }
  
      public ContextAwareTagValueExpression(TagAttribute tagAttribute, ValueExpression valueExpression)
      {
          _location = tagAttribute.getLocation();
          _qName = tagAttribute.getQName();
          _wrapped = valueExpression;
      }
  
      @Override
      public Class<?> getExpectedType()
      {
          return _wrapped.getExpectedType();
      }
  
      @Override
      public Class<?> getType(ELContext context)
      {
          try
          {
              return _wrapped.getType(context);
          }
          catch (PropertyNotFoundException pnfe)
          {
              throw new ContextAwarePropertyNotFoundException(getLocation(), getLocalExpressionString(), getQName(),pnfe);
          }
          catch (ELException e)
          {
              throw new ContextAwareELException(getLocation(), getLocalExpressionString(), getQName(), e);
          }
      }
  
      @Override
      public Object getValue(ELContext context)
      {
          try
          {
              return _wrapped.getValue(context);
          }
          catch (PropertyNotFoundException pnfe)
          {
              throw new ContextAwarePropertyNotFoundException(getLocation(), getLocalExpressionString(), getQName(),pnfe);
          }
          catch (ELException e)
         {
             throw new ContextAwareELException(getLocation(), getLocalExpressionString(), getQName(), e);
         }
         //Not necessary because NullPointerException by null context never occur and should not be wrapped
         //catch (Exception e)
         //{
         //    throw new ContextAwareException(getLocation(), getLocalExpressionString(), getQName(), e);
         //}
     }
     
     private String getLocalExpressionString()
     {
         String expressionString = null;
         try
         {
             expressionString = getExpressionString();
         }
         catch (Throwable t)
         {
             //swallo it because it is not important
         }
         return expressionString;
     }
 
     @Override
     public boolean isReadOnly(ELContext context)
     {
         try
         {
             return _wrapped.isReadOnly(context);
         }
         catch (PropertyNotFoundException pnfe)
         {
             throw new ContextAwarePropertyNotFoundException(getLocation(), getLocalExpressionString(), getQName(),pnfe);
         }
         catch (ELException e)
         {
             throw new ContextAwareELException(getLocation(), getLocalExpressionString(), getQName(), e);
         }
     }
 
     @Override
     public void setValue(ELContext context, Object value)
     {
         try
         {
             _wrapped.setValue(context, value);
         }
         catch (PropertyNotFoundException pnfe)
         {
             throw new ContextAwarePropertyNotFoundException(getLocation(), getLocalExpressionString(), getQName(),pnfe);
         }
         catch (PropertyNotWritableException pnwe)
         {
             throw new ContextAwarePropertyNotWritableException(getLocation(), getLocalExpressionString(),
                                                                getQName(), pnwe);
         }
         catch (ELException e)
         {
             throw new ContextAwareELException(getLocation(), getLocalExpressionString(), getQName(), e);
         }
     }
     
     @Override
     public boolean equals(Object obj)
     {
         return _wrapped.equals(obj);
     }
 
     @Override
     public String getExpressionString()
     {
         return _wrapped.getExpressionString();
     }
 
     @Override
     public int hashCode()
     {
         return _wrapped.hashCode();
     }
 
     @Override
     public boolean isLiteralText()
     {
         return _wrapped.isLiteralText();
     }
 
     @Override
     public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException
     {
         _wrapped = (ValueExpression) in.readObject();
         _location = (Location) in.readObject();
         _qName = in.readUTF();
     }
 
     @Override
     public void writeExternal(ObjectOutput out) throws IOException
     {
         out.writeObject(_wrapped);
         out.writeObject(_location);
         out.writeUTF(_qName);
     }
 
     @Override
     public String toString()
     {
         return _location + ": " + _wrapped;
     }
 
     @Override
     public ValueExpression getWrapped()
     {
         return _wrapped;
     }
 
     @Override
     public Location getLocation()
     {
         return _location;
     }
     
     @Override
     public String getQName()
     {
         return _qName;
     }
     
     @Override
     public ValueReference getValueReference(ELContext context)
     {
         try
         {
             return getWrapped().getValueReference(context);
         }
         catch (PropertyNotFoundException pnfe)
         {
             throw new ContextAwarePropertyNotFoundException(getLocation(), getExpressionString(), getQName() ,  pnfe);
         }
         catch (ELException e)
         {
             throw new ContextAwareELException(getLocation(), getExpressionString(), getQName(),  e);
         }
     }
 }