package wox.serial;

import java.lang.reflect.*;

/**
 * Version: 1.0
 * Author: Carlos R. Jaimez Gonzalez
 * Author: Simon M. Lucas
 * Site: http://woxserializer.sourceforge.net/
 *
 * Version: 1.5
 * Author: Steven M Lewis
 *
 * Version: 2.0
 * Author: George Smith
 * SVN: http://svn.xp-dev.com/svn/WOX2/
 * Note: XML form for vs 2 is more compact and therefor incompatible with vs 1
 */

public class DefaultObjectHandler extends AbstractHandler implements WoxDefaultHandler
{
    public static final DefaultObjectHandler INSTANCE = new DefaultObjectHandler();

    protected DefaultObjectHandler()
    {
    }

    public boolean isFor( Class pType )
    {
        return true;
    }

    @Override
    public String[] getForReadObjectWoxTypeNames()
    {
        return null; // Ask Us
    }

    @Override
    public Class getNativeTypeFor( WoxHandlers pWoxHandlers, String pWoxType )
    {
        Class zType = commonNativeType( pWoxHandlers, pWoxType );
        if ( zType == null )
        {
            throw new NullPointerException( "No Native Type for Wox Type: " + pWoxType );
        }
        return zType;
    }

    @Override
    public String getWoxTypeFor( WoxHandlers pWoxHandlers, Class pType, Field pField, boolean pJustType )
    {
        return commonWoxType( pWoxHandlers, pType, null, pJustType );
    }

    @Override
    public boolean willReadObjectForWoxType( String pWoxType )
    {
        return true;
    }

    @Override
    public Object readObject( WoxHandlers pWoxHandlers, WoxReader pWoxReader, XMLreader pReader )
    {
        XMLreader zSubtree = pReader.createSubtreeReader();
        zSubtree.readStartElement(); //position the cursor to our element

        try
        {
            String zWoxTypeName = pReader.getAttribute( Serial.TYPE );

            Class zType = getNativeTypeFor( pWoxHandlers, zWoxTypeName );

            if ( zType == null )
            {
                throw new ApplicationException( "Unable to determine Native Type for Wox Type: " + zWoxTypeName );
            }

            if ( zType.isEnum() )
            {
                String value = pReader.getAttribute( Serial.VALUE );
                //noinspection unchecked
                return Enum.valueOf( zType, value );
            }
            Object zInstance = Util.createInstance( zType, zWoxTypeName );

            processFields( pWoxHandlers, pWoxReader, zSubtree, zType, zInstance );

            return zInstance;
        }
        catch ( Exception e )
        {
            throw new ApplicationException( "Default Object Handler ReadStartElement Exception is: " + e.getMessage(), e );
        }
        finally
        {
            consume( zSubtree );
        }
    }

    @Override
    public void writeObject( WoxHandlers pWoxHandlers, WoxWriter pWoxWriter, Object pObject, Field pField, XMLwriter pWriter, boolean pJustType )
    {
        Class zType = pObject.getClass();
        pWriter.writeStartElement( Serial.OBJECT );
        pWriter.writeAttributeString( Serial.TYPE, commonWoxType( pWoxHandlers, zType, pField, pJustType ) );

        if ( pJustType )
        {
            processFields( pWoxHandlers, pWoxWriter, pWriter, pJustType, zType, pObject );
        }
        else if ( zType.isEnum() )
        {
            pWriter.writeAttributeString( Serial.VALUE, pObject.toString() );
        }
        else
        {
            pWriter.writeAttributeString( Serial.ID, pWoxWriter.createIDfor( pObject ) );

            processFields( pWoxHandlers, pWoxWriter, pWriter, pJustType, zType, pObject );
        }

        pWriter.writeEndElement();
    }

    @Override
    public boolean supportsJustTypeWriting()
    {
        return true;
    }
}