/*

  *  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.shared_impl.renderkit;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import javax.el.ValueExpression;

 import javax.faces.FacesException;

 import javax.faces.component.UIOutput;

 import javax.faces.component.UISelectMany;

 import javax.faces.context.FacesContext;

 import javax.faces.convert.Converter;

 import javax.faces.convert.ConverterException;

 import java.lang.reflect.Array;

 import java.util.ArrayList;

 import java.util.List;

 /**

  * The util methods in this class are shared between the javax.faces.component package and

  * the org.apache.myfaces.renderkit package.

  * Please note: Any changes here must also apply to the class in the other package!

  *

  * @author Manfred Geiler (latest modification by $Author: skitching $)

  * @version $Revision: 673827 $ $Date: 2008-07-03 16:46:23 -0500 (Thu, 03 Jul 2008) $

  */

 class _SharedRendererUtils

 {

     static Converter findUIOutputConverter(FacesContext facesContext, UIOutput component)

     {

         // Attention!

         // This code is duplicated in jsfapi component package.

         // If you change something here please do the same in the other class!

         Converter converter = component.getConverter();

         if (converter != null) return converter;

         //Try to find out by value expression

         ValueExpression expression = component.getValueExpression("value");

         if (expression == null) return null;

         Class valueType = expression.getType(facesContext.getELContext());

         if (valueType == null) return null;

         if (Object.class.equals(valueType)) return null;    //There is no converter for Object class

         try

         {

             return facesContext.getApplication().createConverter(valueType);

         }

         catch (FacesException e)

         {

             log(facesContext, "No Converter for type " + valueType.getName() + " found", e);

             return null;

         }

     }

     static Object getConvertedUISelectManyValue(FacesContext facesContext,

                                                 UISelectMany component,

                                                 String[] submittedValue)

             throws ConverterException

     {

         // Attention!

         // This code is duplicated in jsfapi component package.

         // If you change something here please do the same in the other class!

         if (submittedValue == null) throw new NullPointerException("submittedValue");

         ValueExpression expression = component.getValueExpression("value");

         Class valueType = null;

         Class arrayComponentType = null;

         if (expression != null)

         {

             //By some strange reason vb.getType(facesContext.getELContext());

             //does not return the same as vb.getValue(facesContext.getELContext()).getClass(),

             //so we need to use this instead.

             Object value = expression.getValue(facesContext.getELContext()); 

             valueType = (value != null) ? value.getClass() :

                 expression.getType(facesContext.getELContext()) ;

             if (valueType != null && valueType.isArray())

             {

                 arrayComponentType = valueType.getComponentType();

             }

         }

         Converter converter = component.getConverter();

         if (converter == null)

         {

             if (valueType == null)

             {

                 // No converter, and no idea of expected type

                 // --> return the submitted String array

                 return submittedValue;

             }

             if (List.class.isAssignableFrom(valueType))

             {

                 // expected type is a List

                 // --> according to javadoc of UISelectMany we assume that the element type

                 //     is java.lang.String, and copy the String array to a new List

                 int len = submittedValue.length;

                 List lst = new ArrayList(len);

                 for (int i = 0; i < len; i++)

                 {

                     lst.add(submittedValue[i]);

                 }

                 return lst;

             }

             if (arrayComponentType == null)

             {

                 throw new IllegalArgumentException("ValueBinding for UISelectMany must be of type List or Array");

             }

             if (Object.class.equals(arrayComponentType)) return submittedValue; //No conversion for Object class

             converter = facesContext.getApplication().createConverter(arrayComponentType);

             if (converter == null)

             {

                 return submittedValue;

             }

         }

         // Now, we have a converter...

         // We determine the type of the component array after converting one of it's elements

         if (expression != null)

         {

             valueType = expression.getType(facesContext.getELContext());

             if (valueType != null && valueType.isArray())

             {

                 if (submittedValue.length > 0) 

                 {

                     arrayComponentType = converter.getAsObject(facesContext, component, submittedValue[0]).getClass();

                 }

             }

         }

         if (valueType == null)

         {

             // ...but have no idea of expected type

             // --> so let's convert it to an Object array

             int len = submittedValue.length;

             Object [] convertedValues = (Object []) Array.newInstance(

                     arrayComponentType==null?Object.class:arrayComponentType,len);

             for (int i = 0; i < len; i++)

             {

                 convertedValues[i]

                     = converter.getAsObject(facesContext, component, submittedValue[i]);

             }

             return convertedValues;

         }

         if (List.class.isAssignableFrom(valueType))

         {

             // Curious case: According to specs we should assume, that the element type

             // of this List is java.lang.String. But there is a Converter set for this

             // component. Because the user must know what he is doing, we will convert the values.

             int len = submittedValue.length;

             List lst = new ArrayList(len);

             for (int i = 0; i < len; i++)

             {

                 lst.add(converter.getAsObject(facesContext, component, submittedValue[i]));

             }

             return lst;

         }

         if (arrayComponentType == null)

         {

             throw new IllegalArgumentException("ValueBinding for UISelectMany must be of type List or Array");

         }

         if (arrayComponentType.isPrimitive())

         {

             //primitive array

             int len = submittedValue.length;

             Object convertedValues = Array.newInstance(arrayComponentType, len);

             for (int i = 0; i < len; i++)

             {

                 Array.set(convertedValues, i,

                           converter.getAsObject(facesContext, component, submittedValue[i]));

             }

             return convertedValues;

         }

         //Object array

         int len = submittedValue.length;

         ArrayList convertedValues = new ArrayList(len); 

         for (int i = 0; i < len; i++)

         {

             convertedValues.add(i, converter.getAsObject(facesContext, component, submittedValue[i])); 

         }

         return convertedValues.toArray((Object[]) Array.newInstance(arrayComponentType, len));

     }

     private static final Log log = LogFactory.getLog(_SharedRendererUtils.class);

     /**

      * This method is different in the two versions of _SharedRendererUtils.

      */

     private static void log(FacesContext context, String msg, Exception e)

     {

         log.error(msg, e);

     }

 }