package dk.thoerup.traininfo.provider;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.StringReader;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;

import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;

import android.util.Log;
import dk.thoerup.traininfo.DepartureBean;

public class XmlDepartureProvider extends DefaultHandler implements DepartureProvider {

	ArrayList<DepartureBean> departures = new ArrayList<DepartureBean>();
	
	
	DepartureBean tempDeparture;
	StringBuilder builder = new StringBuilder(512);
	
	@Override
	public void lookupDepartures(String station) {
		departures.clear();
		try
		{	
			String doc = getUrlContents("http://t-hoerup.dk/tog/xml_display.php?stationname="+station);
			
			InputSource source = new InputSource( new StringReader(doc));
			
			SAXParserFactory spf = SAXParserFactory.newInstance();
            SAXParser sp = spf.newSAXParser();
            XMLReader xr = sp.getXMLReader();

			xr.setContentHandler(this);
			xr.setErrorHandler(this);
			xr.setDTDHandler(this);
			xr.parse(source);
		} catch (Exception e) {
			Log.e("XmlDepartureProvider", "looupFunction", e);
		}
	}
	
	@Override
	public List<DepartureBean> getDepartures() {
		return departures;
	}

	private String getUrlContents(String uri) throws IOException
	{
		URL url = new URL(uri);		
		URLConnection conn = url.openConnection();
		conn.setConnectTimeout(5000);
		InputStream stream = conn.getInputStream();

		BufferedReader in = new BufferedReader(new InputStreamReader(stream, "ISO-8859-1"),8192);

		StringBuilder sbuilder = new StringBuilder();

		String line;
		while ( (line = in.readLine()) != null) {
			sbuilder.append(line);
			sbuilder.append("\r\n");
		}

		return sbuilder.toString();
	}
	
	// this can be called several times fore the same text-node if there are many chardata / lines
	@Override
	public void characters (char ch[], int start, int length) 
	{		
		for (int i= start; i<start+length; i++)
			builder.append(ch[i]);	
	}
	
	@Override
	public void startElement (String uri, String name, String qName, Attributes atts)throws SAXException
	{
		if (name.equalsIgnoreCase("train"))
			tempDeparture = new DepartureBean();
		
		builder.setLength(0); //reset StringBuilder
	}
	
	@Override
	public void endElement (String uri, String name, String qName) throws SAXException
	{
		if (name.equals("train")) {
			departures.add( tempDeparture );
		} else if (name.equals("time")) {
			tempDeparture.setTime(builder.toString());
		} else if (name.equals("updated")) {
			tempDeparture.setLastUpdate(builder.toString());
		} else if (name.equals("trainnumber")) {
			tempDeparture.setTrainNumber(builder.toString());
		} else if (name.equals("destination")) {
			tempDeparture.setDestination(builder.toString());
		} else if (name.equals("origin")) {
			tempDeparture.setOrigin(builder.toString());
		} else if (name.equals("location")) {
			tempDeparture.setLocation(builder.toString());
		} else if (name.equals("status")) {
			tempDeparture.setStatus(builder.toString());
		} else if (name.equals("note")) {
			tempDeparture.setNote(builder.toString());
		} 
	}
}