/*

  * Copyright 1999,2004 The Apache Software Foundation.

  * 

  * Licensed under the Apache License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  * 

  *      http://www.apache.org/licenses/LICENSE-2.0

  * 

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.apache.commons.feedparser;

 import java.util.HashSet;

 import org.apache.commons.feedparser.impl.DebugFeedParserListener;

 import org.apache.commons.feedparser.locate.AnchorParser;

 import org.apache.commons.feedparser.locate.AnchorParserException;

 import org.apache.commons.feedparser.locate.AnchorParserListener;

 /**

  *

  * Experimental class to play with supporting XFN.  HTML parsing in general is

  * interesting because I could start with the AnchorParser and move to an HTML

  * parser but that might be too generic.

  * 

  * @author <a href="mailto:burton@apache.org">Kevin A. Burton (burtonator)</a>

  * @version $Id: HTMLFeedParser.java 373614 2006-01-30 22:31:21Z mvdb $

  */

 public class HTMLFeedParser extends BaseParser {

     public static final HashSet XFN_RELATIONS = new HashSet();

     public static void parse( String content, final FeedParserListener listener ) throws Exception {

         if ( listener instanceof FeedDirectoryParserListener == false )

             return;

         //FIXME: only convert to using XFN if these types of links are detected.

         //If its just a plain XHTML file then we shouldn't use this interface.

         //Also FeedVersion needs to be called.

         final FeedDirectoryParserListener directoryParserLisener =

             (FeedDirectoryParserListener)listener;

         directoryParserLisener.init();

         final FeedParserState state = new FeedParserState();

         AnchorParserListener alistener = new AnchorParserListener() {

                 public void setContext( Object context ) {}

                 public Object getResult() { return null; }

                 public boolean onAnchor( String href, String rel, String title )

                     throws AnchorParserException {

                     try {

                         if ( rel == null || "".equals( rel ) )

                             return true;

                         //right now these aren't valid here

                         String description = null;

                         String feed = null;

                         //FIXME: only include onItem when we have at least ONE XFN

                         //relations that valid.

                         directoryParserLisener.onItem( state, title, href, description, feed );

                         String[] rels = rel.split( " " );

                         for ( int i = 0; i < rels.length; ++i ) {

                             String current = rels[i];

                             //FIXME: when this current rel is NOT part of any XFN

                             //spec we should not be using the feed parser listener

                             //because it might just be a nofollow link or such.

                             boolean isXFriendRel = XFN_RELATIONS.contains( current );

                             if ( isXFriendRel ) {

                                 directoryParserLisener.onRelation( state,

                                                                    current );

                                 directoryParserLisener.onRelationEnd();

                             }

                         }

                         directoryParserLisener.onItemEnd();

                         //split this into individual rels... then call them.

                         return true;

                     } catch ( Exception e ) {

                         throw new AnchorParserException( e );

                     }

                 }

             };

         AnchorParser.parse( content, alistener );

         directoryParserLisener.finished();

     }

     public static void main( String[] args ) throws Exception {

         FeedParserListener listener = new DebugFeedParserListener();

         parse( "<a href='http://jane-blog.example.org/' rel='sweetheart date met'>Jane</a> ",

                listener );

     }

     static {

         XFN_RELATIONS.add( "contact" );

         XFN_RELATIONS.add( "acquaintance" );

         XFN_RELATIONS.add( "friend" );

         XFN_RELATIONS.add( "met" );

         XFN_RELATIONS.add( "co-worker" );

         XFN_RELATIONS.add( "colleague" );

         XFN_RELATIONS.add( "co-resident" );

         XFN_RELATIONS.add( "neighbor" );

         XFN_RELATIONS.add( "child" );

         XFN_RELATIONS.add( "parent" );

         XFN_RELATIONS.add( "sibling" );

         XFN_RELATIONS.add( "spouse" );

         XFN_RELATIONS.add( "kin" );

         XFN_RELATIONS.add( "muse" );

         XFN_RELATIONS.add( "crush" );

         XFN_RELATIONS.add( "date" );

         XFN_RELATIONS.add( "sweetheart" );

         XFN_RELATIONS.add( "me" );

     }

 }