/*
 * APP.JS
 *
 * Notice that AppFog passes the listen port for your app in an environment variable,
 * accessed by process.env.VCAP_APP_PORT
 *
 *
*/

//REQUIREMENTS
var
   express = require("express"),
   logger = require("morgan"),
   WebSocketServer = require("ws").Server;

//MASTER VARIABLE DEFINITIONS
var
   httpPort = process.env.PORT || 3000,
   wsPort = 3001,
   wss = new WebSocketServer({port:wsPort}),
   wsgrid = {},
   app = express();

//SHORT FUNCTION DEFINITIONS
var
   //Handle incoming messages from clients
   wsHandleMessage = function(rawMessage) {
      var
         messageArray = rawMessage.split(":"),
         messageType = messageArray[0],
         message = messageArray[1];

      switch(messageType){
         case "broadcast":
            var originClientID = messageArray[2];
            for(var wsid in wsgrid){ //broadcast to every client
               safeSend(wsid,rawMessage);
            }
         break;
      }
   },

   //Safely send a message to a client
   safeSend = function(wsid,msg){
      var ts = new Date().getTime();
      console.log(ts,wsid,msg);
      if(wsgrid[wsid].readyState == wsgrid[wsid].OPEN){ wsgrid[wsid].send(msg); }
   },

   //Safely close a client websocket connection
   closeSocket = function(wsid){delete wsgrid[wsid];},

   //Generate a unique client handle
   generateUIDNotMoreThan1million = function() { return ("0000" + (Math.random()*Math.pow(36,4) << 0).toString(36)).slice(-4); },

   //create the heartbeat function with access to local variables
   hb = function(wsid){
      if(wsgrid[wsid].readyState != wsgrid[wsid].OPEN){
         closeSocket(wsid);
         console.log("WS "+wsid+" has disconnected.");
         return;
      }
      safeSend(wsid,"hb");
      setTimeout(function(){hb(wsid);},5000);
   };

//LISEN UP SERVER!

//Create a websocket server
wss.on('connection', function(ws) {
   var wsid = generateUIDNotMoreThan1million(); //my own custom hack to the ws object to give it an easily accessible id
   wsgrid[wsid] = ws;
   wsgrid[wsid].on('message', wsHandleMessage);
   safeSend(wsid,"connected:"+wsid);
   hb(wsid); //start the heartbeat
});

//HTTP Server Middleware
app.get("/", function(req, res) {res.sendfile("index.html");});
app.get("/*", function(req, res) {res.sendfile("script.js");});

//HTTP Server
app.listen(httpPort);

console.log("Server running.");