package com.sun.grizzly.samples.comet;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.*;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.sun.grizzly.comet.CometContext;
import com.sun.grizzly.comet.CometEngine;
import com.sun.grizzly.comet.CometEvent;
import com.sun.grizzly.comet.CometHandler;

public class MyCometServlet extends HttpServlet {
    
    private class CometMsgHandler implements CometHandler<HttpServletResponse> {
        
        private HttpServletResponse response;
        
        public void onEvent(CometEvent event) throws IOException {
            if (CometEvent.NOTIFY == event.getType()) {
                PrintWriter writer = response.getWriter();
                writer.write((String)event.attachment());
                writer.flush();
            }
        }
        
        public void onInitialize(CometEvent event) throws IOException {
        }
        
        public void onInterrupt(CometEvent event) throws IOException {
            removeThisFromContext();
        }
        
        public void onTerminate(CometEvent event) throws IOException {
            removeThisFromContext();
        }
        
        public void attach(HttpServletResponse attachment) {
            this.response = attachment;
        }

        private void removeThisFromContext() throws IOException {
            response.getWriter().close();
        }
    }
    
    private static final long serialVersionUID = 1L;
    
    @Override
    public void init(ServletConfig config) throws ServletException {
    }
    
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse res)
            throws ServletException, IOException {
        doPost(req, res);
    }
    
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse res)
            throws ServletException, IOException {
        String contextPath = req.getParameter("client");
        String message = req.getParameter("message");
        CometEngine engine = CometEngine.getEngine();
        if (message == null) {
            if (contextPath != null) {
	        CometContext cc = engine.getCometContext(contextPath);
	        if (cc == null) {
	            cc = engine.register(contextPath);
                    // how long to hold client 
	            cc.setExpirationDelay(30000 * 1000);
	            CometMsgHandler handler = new CometMsgHandler();
	            handler.attach(res);
	            cc.addCometHandler(handler);
                    // to fix
                    cc.notify("init ...");
	        } 
            }
        } else {
	    CometContext cc = engine.getCometContext(contextPath);
            if (cc != null) {
                cc.notify(message);
            }
        }
    }
}