/*
 * Created on Jul 13, 2009
 * Created by Paul Gardner
 * 
 * Copyright 2009 Vuze, Inc.  All rights reserved.
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License only.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
 */


package com.aelitis.azureus.core.subs.impl;

import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.InetSocketAddress;
import java.net.URL;
import java.util.Date;

import org.gudy.azureus2.core3.config.COConfigurationManager;

import org.gudy.azureus2.core3.util.Debug;
import org.gudy.azureus2.core3.util.TimeFormatter;
import org.gudy.azureus2.core3.util.UrlUtils;
import org.gudy.azureus2.core3.xml.util.XUXmlWriter;

import org.gudy.azureus2.plugins.PluginInterface;
import org.gudy.azureus2.plugins.tracker.web.TrackerWebPageRequest;
import org.gudy.azureus2.plugins.tracker.web.TrackerWebPageResponse;
import org.gudy.azureus2.plugins.utils.search.SearchResult;
import org.gudy.azureus2.plugins.utils.subscriptions.Subscription;
import org.gudy.azureus2.plugins.utils.subscriptions.SubscriptionManager;
import org.gudy.azureus2.plugins.utils.subscriptions.SubscriptionResult;

import com.aelitis.azureus.core.rssgen.RSSGeneratorPlugin;

public class 
SubscriptionRSSFeed 
	implements RSSGeneratorPlugin.Provider
{
	private static final String PROVIDER = "subscriptions";
	
	private SubscriptionManagerImpl		manager;
	private PluginInterface				plugin_interface;
	
	private RSSGeneratorPlugin		generator;
	
	protected
	SubscriptionRSSFeed(
		SubscriptionManagerImpl	_manager,
		PluginInterface			_plugin_interface )
	{
		manager 			= _manager;
		plugin_interface	= _plugin_interface;
				
		generator	= RSSGeneratorPlugin.getSingleton();
		
		if ( generator != null ){
			
			generator.registerProvider( PROVIDER, this );
		}
	}
		
	public boolean
	isEnabled()
	{
		return( manager.isRSSPublishEnabled());
	}
	
	public String
	getFeedURL()
	{
		return( generator==null?"Feature Disabled":( generator.getURL() + PROVIDER ));
	}
	
	public boolean
	generate(
		TrackerWebPageRequest		request,
		TrackerWebPageResponse		response )
	
		throws IOException
	{
		InetSocketAddress	local_address = request.getLocalAddress();
		
		if ( local_address == null ){
			
			return( false );
		}
		
		URL	url	= request.getAbsoluteURL();
					
		String path = url.getPath();
		
		path = path.substring( PROVIDER.length()+1);
		
		try{
			SubscriptionManager sman = plugin_interface.getUtilities().getSubscriptionManager();
	
			Subscription[] 	subs = sman.getSubscriptions();
			
			OutputStream os = response.getOutputStream();
	
			PrintWriter pw = new PrintWriter(new OutputStreamWriter( os, "UTF-8" ));
	
			if ( path.length() <= 1 ){
				
				response.setContentType( "text/html; charset=UTF-8" );
				
				pw.println( "<HTML><HEAD><TITLE>Vuze Subscription Feeds</TITLE></HEAD><BODY>" );
				
				for ( Subscription s: subs ){
	
					if ( s.isSearchTemplate()){
						
						continue;
					}
					
					String	name = s.getName();
									
					pw.println( "<LI><A href=\"" + PROVIDER + "/" + s.getID() + "\">" + name + "</A></LI>" );
				}
				
				pw.println( "</BODY></HTML>" );
				
			}else{
				
				String	id = path.substring( 1 );
				
				Subscription	subscription = null;
				
				for ( Subscription s: subs ){
					
					if ( s.getID().equals( id )){
						
						subscription = s;
						
						break;
					}
				}
				
				if ( subscription == null ){
					
					response.setReplyStatus( 404 );
					
					return( true );
				}
				
				URL	feed_url = url;
	
					// absolute url is borked as it doesn't set the host properly. hack 
				
				String	host = (String)request.getHeaders().get( "host" );
				
				if ( host != null ){
					
					int	pos = host.indexOf( ':' );
					
					if ( pos != -1 ){
						
						host = host.substring( 0, pos );
					}
					
					feed_url = UrlUtils.setHost( url, host );
				}
				
				response.setContentType( "application/xml" );
				
				pw.println( "<?xml version=\"1.0\" encoding=\"utf-8\"?>" );
				
				pw.println( 
						"<rss version=\"2.0\" " + 
						"xmlns:vuze=\"http://www.vuze.com\" " +
						"xmlns:media=\"http://search.yahoo.com/mrss/\" " +
						"xmlns:atom=\"http://www.w3.org/2005/Atom\" " +
						"xmlns:itunes=\"http://www.itunes.com/dtds/podcast-1.0.dtd\">" );
				
				pw.println( "<channel>" );
				
				String channel_title = "Vuze Subscription: " + escape( subscription.getName());
						
				pw.println( "<title>" + channel_title + "</title>" );
				pw.println( "<link>http://vuze.com</link>" );
				pw.println( "<atom:link href=\"" + escape( feed_url.toExternalForm()) + "\" rel=\"self\" type=\"application/rss+xml\" />" );
				
				pw.println( "<description>Vuze RSS Feed for subscription " + escape( subscription.getName()) + "</description>" );
				
				pw.println("<itunes:image href=\"http://www.vuze.com/img/vuze_icon_128.png\"/>");
				pw.println("<image><url>http://www.vuze.com/img/vuze_icon_128.png</url><title>" + channel_title + "</title><link>http://vuze.com</link></image>");
				
						
				SubscriptionResult[] results = subscription.getResults();

											
				String	feed_date_key = "subscriptions.feed_date." + subscription.getID();
				
				long feed_date = COConfigurationManager.getLongParameter( feed_date_key );
	
				boolean new_date = false;
				
				for ( SubscriptionResult result: results ){
				
					Date date = (Date)result.getProperty( SearchResult.PR_PUB_DATE );
					
					long 	millis = date.getTime();
					
					if ( millis > feed_date ){
						
						feed_date = millis;
						
						new_date = true;
					}
				}
				
				if ( new_date ){
					
					COConfigurationManager.setParameter( feed_date_key, feed_date );
				}
				
				pw.println(	"<pubDate>" + TimeFormatter.getHTTPDate( feed_date ) + "</pubDate>" );
	
				
				for ( SubscriptionResult result: results ){
											
					try{
		  				pw.println( "<item>" );
		  				
		  				String	name = (String)result.getProperty( SearchResult.PR_NAME );
		  				
		  				pw.println( "<title>" + escape( name ) + "</title>" );
		  					
						Date date = (Date)result.getProperty( SearchResult.PR_PUB_DATE );
						
						if ( date != null ){
		  
							pw.println(	"<pubDate>" + TimeFormatter.getHTTPDate( date.getTime()) + "</pubDate>" );
						}
						
						String	uid = (String)result.getProperty( SearchResult.PR_UID );
						
						if ( uid != null ){
		  				
							pw.println( "<guid isPermaLink=\"false\">" + escape(uid ) + "</guid>" );
						}
						
						String	link = (String)result.getProperty( SearchResult.PR_DOWNLOAD_LINK );
						Long	size = (Long)result.getProperty( SearchResult.PR_SIZE );

						if ( link != null ){
							
							pw.println( "<link>" + link + "</link>" );
						

							if ( size != null ){
							
								pw.println( "<media:content fileSize=\"" + size + "\" url=\"" + link + "\"/>" );
							}
						}
						
						if ( size != null ){

							pw.println( "<vuze:size>" + size + "</vuze:size>" );
						}
						
						Long	seeds = (Long)result.getProperty( SearchResult.PR_SEED_COUNT );
						
						if ( seeds != null ){
							
							pw.println( "<vuze:seeds>" + seeds + "</vuze:seeds>" );
						}
						
						Long	peers = (Long)result.getProperty( SearchResult.PR_LEECHER_COUNT );
						
						if ( peers != null ){
							
							pw.println( "<vuze:peers>" + peers + "</vuze:peers>" );
						}

						Long	rank = (Long)result.getProperty( SearchResult.PR_RANK );
						
						if ( rank != null ){
							
							pw.println( "<vuze:rank>" + rank + "</vuze:rank>" );
						}

						
		  				pw.println( "</item>" );
		  				
					}catch( Throwable e ){
						
						Debug.out(e);
					}
				}
			
				pw.println( "</channel>" );
				
				pw.println( "</rss>" );
			}
			
			pw.flush();
			
		}catch( Throwable e ){
			
			Debug.out( e );
			
			throw( new IOException( Debug.getNestedExceptionMessage( e )));
		}
		
		return( true );
	}
	
	protected String
	escape(
		String	str )
	{
		return( XUXmlWriter.escapeXML(str));
	}

	protected String
	escapeMultiline(
		String	str )
	{
		return( XUXmlWriter.escapeXML(str.replaceAll("[\r\n]+", "<BR>")));
	}
}
