package net.spy.digg.parsers;

 import java.io.IOException;

 import java.util.HashMap;

 import java.util.Map;

 import org.w3c.dom.Document;

 import org.w3c.dom.Node;

 import org.w3c.dom.NodeList;

 import org.xml.sax.SAXException;

 import net.spy.digg.TopicContainer;

 /**

  * Parse the topics.

  */

 public class TopicsParser extends BaseParser {

         private final Map<String, TopicContainer> containers

                 =new HashMap<String, TopicContainer>();

         @Override

         protected String getRootElementName() {

                 return "topics";

         }

         @Override

         protected void handleDocument(Document doc)

                 throws SAXException, IOException {

                 // Build out the topics.

                 final NodeList nl=doc.getDocumentElement().getElementsByTagName("topic");

                 for(int i=0; i<nl.getLength(); i++) {

                         final Node n=nl.item(i);

                         final String name=getAttr(n, "name");

                         final String shortName=getAttr(n, "short_name");

                         final NodeList nlTmp=n.getChildNodes();

                         Node cn=null;

                         for(int j=0; j<nlTmp.getLength(); j++) {

                                 if(nlTmp.item(j).getNodeName().equals("container")) {

                                         cn=nlTmp.item(j);

                                 }

                         }

                         assert cn != null : "Couldn't find a container";

                         assert cn.getNodeName().equals("container")

                                 : "Expected container, got " + cn.getNodeName();

                         final String cname=getAttr(cn, "name");

                         final String cshortName=getAttr(cn, "short_name");

                         TopicContainer tc=containers.get(cshortName);

                         if(tc == null) {

                                 tc=new TopicContainerImpl(cname, cshortName);

                                 containers.put(cshortName, tc);

                         }

                         tc.add(new TopicImpl(name, shortName));

                 }

         }

         /**

          * Get a map of all topic containers by short name.

          */

         public Map<String, TopicContainer> getContainers() {

                 return containers;

         }

 }