/*************************************************************************
 * 
 * ADOBE CONFIDENTIAL __________________
 * 
 * Copyright 2002 - 2007 Adobe Systems Incorporated All Rights Reserved.
 * 
 * NOTICE: All information contained herein is, and remains the property of Adobe Systems Incorporated and its suppliers, if any. The intellectual and technical concepts contained herein are
 * proprietary to Adobe Systems Incorporated and its suppliers and may be covered by U.S. and Foreign Patents, patents in process, and are protected by trade secret or copyright law. Dissemination of
 * this information or reproduction of this material is strictly forbidden unless prior written permission is obtained from Adobe Systems Incorporated.
 **************************************************************************/
package flex.messaging.io.amf.translator.decoder;

import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;

import flex.messaging.io.amf.translator.TranslationException;

/**
 * Decodes a java.lang.reflect.Array, java.util.Collection, java.lang.String (using toCharArray), to a java.util.Collection instance.
 * <p>
 * If the desired Collection class is an interface then an instance of a standard implementation will be created.
 * </p>
 * <p>
 * If java.util.SortedSet is desired, then a java.util.TreeSet will be created.
 * </p>
 * <p>
 * If a java.util.Set is desired, then a java.util.HashSet will be created.
 * </p>
 * <p>
 * If a java.util.List is desired, then a java.util.ArrayList will be created.
 * </p>
 * <p>
 * If a java.util.Collection is desired, then a java.util.ArrayList will be created.
 * </p>
 * 
 * @see java.util.Collection
 * 
 * @exclude
 */
public class CollectionDecoder extends ActionScriptDecoder
{
    @Override
    public boolean hasShell()
    {
        return true;
    }

    protected boolean isSuitableCollection(Object encodedObject, Class desiredClass)
    {
        return (encodedObject instanceof Collection && desiredClass.isAssignableFrom(encodedObject.getClass()));
    }

    @Override
    public Object createShell(Object encodedObject, Class desiredClass)
    {
        Collection col = null;

        try
        {
            if (encodedObject != null)
            {
                if (isSuitableCollection(encodedObject, desiredClass))
                {
                    col = (Collection) encodedObject;
                }
                else
                {
                    if (desiredClass.isInterface())
                    {
                        if (List.class.isAssignableFrom(desiredClass))
                        {
                            col = new ArrayList();
                        }
                        else if (SortedSet.class.isAssignableFrom(desiredClass))
                        {
                            col = new TreeSet();
                        }
                        else if (Set.class.isAssignableFrom(desiredClass))
                        {
                            col = new HashSet();
                        }
                        else if (Collection.class.isAssignableFrom(desiredClass))
                        {
                            col = new ArrayList();
                        }
                    }
                    else
                    {
                        col = (Collection) desiredClass.newInstance();
                    }
                }
            }
            else
            {
                col = (Collection) desiredClass.newInstance();
            }
        }
        catch (Exception e)
        {
            TranslationException ex = new TranslationException("Could not create Collection " + desiredClass, e);
            ex.setCode("Server.Processing");
            throw ex;
        }

        if (col == null)
        {
            DecoderFactory.invalidType(encodedObject, desiredClass);
        }

        return col;
    }

    @Override
    public Object decodeObject(Object shell, Object encodedObject, Class desiredClass)
    {
        if (shell == null || encodedObject == null)
            return null;

        // Don't decode if we already have a suitable Collection.
        if (isSuitableCollection(encodedObject, desiredClass))
        {
            return encodedObject;
        }

        return decodeCollection((Collection) shell, encodedObject);
    }

    protected Collection decodeCollection(Collection collectionShell, Object encodedObject)
    {
        Object obj = null;

        if (encodedObject instanceof String)
        {
            encodedObject = ((String) encodedObject).toCharArray();
        }
        else if (encodedObject instanceof Collection)
        {
            encodedObject = ((Collection) encodedObject).toArray();
        }

        int len = Array.getLength(encodedObject);

        for (int i = 0; i < len; i++)
        {
            obj = Array.get(encodedObject, i);
            collectionShell.add(obj);
        }

        return collectionShell;
    }
}