package com.appenginefan.xmpptest;

import java.io.IOException;
import java.util.logging.Logger;

import javax.servlet.http.*;

import Eliza.ElizaParse;

import com.google.appengine.api.datastore.DatastoreServiceFactory;
import com.google.appengine.api.datastore.Entity;
import com.google.appengine.api.datastore.EntityNotFoundException;
import com.google.appengine.api.datastore.Key;
import com.google.appengine.api.datastore.KeyFactory;
import com.google.appengine.api.xmpp.JID;
import com.google.appengine.api.xmpp.Message;
import com.google.appengine.api.xmpp.MessageBuilder;
import com.google.appengine.api.xmpp.XMPPService;
import com.google.appengine.api.xmpp.XMPPServiceFactory;

@SuppressWarnings("serial")
public class XmpptestServlet
    extends HttpServlet {

  private static final Logger LOG =
      Logger.getLogger(XmpptestServlet.class.getName());

  private static final String LINE = "line";

  @Override
  public void doPost(HttpServletRequest req,
      HttpServletResponse resp) throws IOException {

    // Parse incoming message
    XMPPService xmpp = XMPPServiceFactory.getXMPPService();
    Message msg = xmpp.parseMessage(req);
    JID jid = msg.getFromJid();
    String body = msg.getBody();
    LOG.info(jid.getId() + " --> JEliza: " + body);
    
    // What was the last line in our conversation?
    Key key = KeyFactory.createKey("chatData", ":"
        + jid.getId());
    Entity lastLineEntity = null;
    try {
      lastLineEntity = 
          DatastoreServiceFactory.getDatastoreService()
              .get(key);
                  
    } catch (EntityNotFoundException e) {
      lastLineEntity = new Entity(key);
      lastLineEntity.setProperty(LINE, "");
    }
    final String lastLine =
        (String) lastLineEntity.getProperty(LINE);

    // Get a response from Eliza
    final StringBuilder response = new StringBuilder();
    final ElizaParse parser = new ElizaParse() {

      @Override
      public void PRINT(String s) {

        // Skip the annoying intro
        if (lastLine.trim().length() > 0
            && s.startsWith("HI! I'M ELIZA")) {
          return;
        }

        // Write all output into a StringBuffer
        response.append(s);
        response.append('\n');
      }
    };
    parser.lastline = lastLine;
    parser.handleLine(body);
    body = response.toString();
    LOG.info(jid.getId() + " <-- JEliza: " + body);

    // Send out response
    msg =
        new MessageBuilder().withRecipientJids(jid)
            .withBody(body).build();
    xmpp.sendMessage(msg);

    // Store the new last line in the datastore. Clear the
    // line
    // in case of "exit"
    if (parser.exit) {
      lastLineEntity.setProperty(LINE, "");
    } else {
      lastLineEntity.setProperty(LINE, parser.lastline);
    }
    DatastoreServiceFactory.getDatastoreService().put(
        lastLineEntity);
  }
}