package geniusweb.runserver;

import java.io.IOException;
import java.util.logging.Level;
import java.util.stream.Collectors;

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

import com.fasterxml.jackson.databind.ObjectMapper;

import geniusweb.protocol.NegoSettings;
import tudelft.utilities.logging.ReportToLogger;
import tudelft.utilities.logging.Reporter;

/**
 * Contains incoming connection to run a Nego. runserver/runsession with the
 * JSON {@link NegoSettings} in the request header. After the session is
 * started, the new Nego ID is returned. This can be used to find back the log
 * files..
 */
@SuppressWarnings("serial")
public class RunNego extends HttpServlet {
	private final Reporter log;
	private final static ObjectMapper jackson = new ObjectMapper();

	public RunNego() {
		this(new ReportToLogger("runserver"));
	}

	public RunNego(Reporter logger) {
		super();
		this.log = logger;
	}

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
	 *      response). Returns
	 *      <ul>
	 *      <li>URL with websocket address to contact the now running party.
	 *      <li>SC_NOT_FOUND (404) if attempt is made to access non-running
	 *      party.
	 *      <li>SC_SERVICE_UNAVAILABLE (503) if there are no free slots to run
	 *      the party.
	 *      <li>SC_EXPECTATION_FAILED (417) if something else goes wrong during
	 *      instantiating the party (then see logs for more details)
	 *      </ul>
	 */
	@Override
	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		String reqstring = request.getReader().lines()
				.collect(Collectors.joining());
		NegoSettings settings;
		try {
			settings = jackson.readValue(reqstring, NegoSettings.class);
		} catch (IOException e) {
			response.sendError(HttpServletResponse.SC_BAD_REQUEST,
					e.getMessage());
			System.err.println("Run request failed " + reqstring);
			e.printStackTrace(); // helpful for debugging run requests
			return;
		}
		log.log(Level.INFO, "request to run Nego: " + settings);
		RunningNego session = new RunningNego(settings,
				RunningNegotiationsRepo.instance(), log);
		session.start();
		// set content type to prevent some browsers
		// trying to parse this (eg as XML)
		response.setContentType("application/json");
		response.getWriter().append(session.getID());
	}

	/**
	 * @see #doGet(HttpServletRequest, HttpServletResponse)
	 */
	@Override
	protected void doPost(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}

}