package dk.thoerup.traininfoservice;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.simpleframework.xml.Serializer;
import org.simpleframework.xml.core.Persister;

import dk.thoerup.android.traininfo.common.StationBean;

/**
 * Servlet implementation class LocateStations
 */
@WebServlet(urlPatterns={"/LocateStations"})
public class LocateStations extends HttpServlet {
	private static final long serialVersionUID = 1L;

	Logger logger = Logger.getLogger( LocateStations.class.toString() );

	StationDAO stationDao = new StationDAO();


	protected String transformToIntList(String input) {		
		String strings[] = input.split(",");

		StringBuffer sb = new StringBuffer();
		sb.append("(");
		for (int i = 0; i<strings.length; i++) {
			if (i>0) {
				sb.append(",");
			}
			sb.append( Integer.parseInt(strings[i])); //by doing the integer conversion we ensure that it really is a integer
		}
		sb.append(")");
		return sb.toString();		
	}


	protected StationBean getStations(HttpServletRequest req) throws SQLException {
		StationBean stations = null;
		if (req.getParameter("latitude") != null && req.getParameter("latitude") != null) {
			
			Statistics.getInstance().incrementStationLookupsLocation();
			
			double latitude = Double.parseDouble( req.getParameter("latitude") );
			double longitude = Double.parseDouble( req.getParameter("longitude") );
			stations = stationDao.getByLocation(latitude, longitude);

		} else if (req.getParameter("name") != null) {
			Statistics.getInstance().incrementStationLookupsName();
			String name = req.getParameter("name").trim();
			stations = stationDao.getByName(name);

		} else if (req.getParameter("list") != null) {
			Statistics.getInstance().incrementStationLookupsFavorites();
			String list = transformToIntList( req.getParameter("list"));
			stations = stationDao.getByList(list);
		}
		return stations;
	}


	protected String formatStations(StationBean stations) throws ServletException {

		Serializer serializer = new Persister();

		ByteArrayOutputStream out = new ByteArrayOutputStream();

		try {
			serializer.write(stations, out);
		} catch (Exception e) {
			throw new ServletException(e);
		}
		
		return out.toString();
	}

	@Override
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {


		try {
			StationBean stations = getStations(request);


			if (stations != null){
				String xml = formatStations(stations);

				response.setContentType("text/xml");
				response.getWriter().print(xml);
			} else {
				response.sendError(400, "not enough parameters");		
			}


		} catch (Exception e) {				
			logger.log(Level.SEVERE, "Exception while finding stations", e);
			response.sendError(500);						
		} 
	}

}