package yarfraw.mapping.backward.impl;

 import static yarfraw.mapping.backward.impl.Rss10MappingUtils.toChannel;

 import javax.xml.bind.JAXBElement;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import yarfraw.core.datamodel.ChannelFeed;

 import yarfraw.core.datamodel.Image;

 import yarfraw.core.datamodel.TextInput;

 import yarfraw.core.datamodel.YarfrawException;

 import yarfraw.generated.rss10.elements.RDF;

 import yarfraw.generated.rss10.elements.TRss10Channel;

 import yarfraw.generated.rss10.elements.TRss10Image;

 import yarfraw.generated.rss10.elements.TRss10TextInput;

 import yarfraw.mapping.backward.ToChannelRss10;

 public class ToChannelRss10Impl implements ToChannelRss10{

   private static final ToChannelRss10 _instance = new ToChannelRss10Impl();

   private static final Log LOG = LogFactory.getLog(ToChannelRss10Impl.class);

   private ToChannelRss10Impl() {}

   public static ToChannelRss10 getInstance(){

     return _instance;

   }

   @SuppressWarnings("unchecked")

   public ChannelFeed execute(RDF rdf) throws YarfrawException {

     if(rdf == null){

       LOG.warn("null rdf Element received, this is not normal. ");

       return null;

     }

     TRss10Channel ch = null;

     TRss10TextInput ti = null;

     TRss10Image img = null;

     for(Object o : rdf.getChannelOrImageOrItem()){

       if (o instanceof JAXBElement) {

         Object val = ((JAXBElement)o).getValue();

         if (val instanceof TRss10Channel) {

           ch = (TRss10Channel) val;

         }else if(val instanceof TRss10TextInput){

           ti = (TRss10TextInput)val;

         }else if(val instanceof TRss10Image){

           img = (TRss10Image)val;

         }

       }

     }

     ChannelFeed channel = toChannel(ch, rdf);

     if(img != null){

       if(channel.getImageOrIcon() != null){

         Rss10MappingUtils.populateImage(channel.getImageOrIcon(), img);

       }else{

         LOG.warn("expecting an <image> element under <channel>");

         Image newImage = new Image();

         newImage.setResource(img.getAbout());

         Rss10MappingUtils.populateImage(newImage, img);

         channel.setImageOrIcon(newImage);

       }

     }

     if(ti != null){

       if(channel.getTexInput() != null){

         Rss10MappingUtils.populateTextinput(channel.getTexInput(), ti);

       }else{

         LOG.warn("expecting an <textinput> element under <channel>");

         TextInput newTextInput = new TextInput();

         newTextInput.setResource(ti.getAbout());

         Rss10MappingUtils.populateTextinput(newTextInput, ti);

         channel.setTexInput(newTextInput);

       }

     }

     return channel;

   }

 }