package wox.serial;

import java.lang.reflect.*;
import org.litesoft.core.typeutils.Objects;
import java.util.*;

/**
 * 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 MapHandler extends AbstractHandler implements WoxIsAHandler
{
    public static final MapHandler INSTANCE = new MapHandler();

    public static final String WOX_TYPE = "map";

    private static final String GENERIC_WOX_TYPE_NAME_STARTS_WITH = WOX_TYPE + "<";

    protected MapHandler()
    {
    }

    @Override
    public boolean isFor( Class pType )
    {
        return Map.class.isAssignableFrom( pType );
    }

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

    @Override
    public Class getNativeTypeFor( WoxHandlers pWoxHandlers, String pWoxType )
    {
        if ( WOX_TYPE.equals( pWoxType ) )
        {
            return HashMap.class;
        }
        if ( pWoxType.startsWith( GENERIC_WOX_TYPE_NAME_STARTS_WITH ) )
        {
            Class zType = commonNativeType( pWoxHandlers, pWoxType );
            if ( zType != null )
            {
                return zType;
            }
        }
        throw new ApplicationException( "No Native Type for Wox Type: " + pWoxType );
    }

    @Override
    public String getWoxTypeFor( WoxHandlers pWoxHandlers, Class pType, Field pField, boolean pJustType )
    {
        if ( null != getGenericTypes( pField ) )
        {
            return commonWoxType( pWoxHandlers, pType, pField, pJustType );
        }
        if ( Map.class.isAssignableFrom( pType ) )
        {
            return WOX_TYPE;
        }
        throw new ApplicationException( "No Wox Type for Native Type: " + pType );
    }

    @Override
    public boolean willReadObjectForWoxType( String pWoxType )
    {
        return WOX_TYPE.equals( pWoxType ) || pWoxType.startsWith( GENERIC_WOX_TYPE_NAME_STARTS_WITH );
    }

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

        try
        {
            Map<Object, Object> zMap = new HashMap<Object, Object>();

            while ( zSubtree.readStartElement() )
            {
                // currently at the "entry"
                //position the cursor in the KEY object
                zSubtree.readStartElement();
                Object zKey = pWoxReader.read( zSubtree );

                //position the cursor in the VALUE object
                zSubtree.readStartElement();
                Object zValue = pWoxReader.read( zSubtree );

                //Add the key and the value
                zMap.put( zKey, zValue );
            }

            return zMap;
        }
        catch ( Exception e )
        {
            throw new ApplicationException( "Map Handler Read Object 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();
        String zWoxTypeName = commonWoxType( pWoxHandlers, zType, pField, pJustType );

        pWriter.writeStartElement( Serial.OBJECT );
        pWriter.writeAttributeString( Serial.TYPE, zWoxTypeName );

        //we already know it is a Map, so, we can simply Enumerate over the entries.
        Map<Object, Object> zMap = Util.cast( pObject );

        if ( !zMap.isEmpty() )
        {
            pWriter.writeAttributeString( Serial.ID, pWoxWriter.createIDfor( pObject ) );

            for ( Map.Entry<Object, Object> zEntry : zMap.entrySet() )
            {
                pWriter.writeStartElement( Serial.OBJECT );
                pWriter.writeAttributeString( Serial.TYPE, Serial.MAP_ENTRY );
                pWoxWriter.write( zEntry.getKey(), pField, pWriter, pJustType );
                pWoxWriter.write( zEntry.getValue(), pField, pWriter, pJustType );
                pWriter.writeEndElement();
            }
        }
        pWriter.writeEndElement();
    }
}