Moonbase

game.js

//
// Moonbase Mayhem
//

var util = require('util');
var events = require('events');

function Game() {
  events.EventEmitter.call(this);

  // Constants
  var MOVINC = 10;
  var BOUNDS = {
    "x": 0,
    "y": 50,
    "w": 720,
    "h": 500,
  }

  // Storage
  var allPlayers = {}
  var allJewels = {}

  // Player Statistics
  var playersTotal = 0;
  var playersCurrent = 0;
  var playersMax = 0;

  // Jewel Statistics
  var jewelsTotal = 0;
  var jewelsCollectedTotal = 0;

  function Jewel(id) {
    this.id = id;
    this.x = 0;
    this.y = 0;

    this.w = 30;
    this.h = 34;
  }

  function Player(id) {
    this.id = id;
    this.x = 0;
    this.y = 0;

    this.w = 55;
    this.h = 95;
    
    this.name = null;
    this.jewelsCollected = 0;
  }

  function placeItem(item) {
    item.x = Math.floor(Math.random() * BOUNDS.w - 20) + BOUNDS.x + 20;
    item.y = Math.floor(Math.random() * BOUNDS.h - 20) + BOUNDS.y + 20;
  }

  function intersects(objA, objB) {
    return objA.x < objB.x + objB.w &&
           objA.x + objA.w > objB.x &&
           objA.y < objB.y + objB.h &&
           objA.y + objA.h > objB.y;
  }

  this.getScoreRoster = function() {
    var scores = []
    for (var p in allPlayers) {
      var player = allPlayers[p];
      if (player.name)
        scores.push([player.name, player.jewelsCollected]);
    }

    return scores.sort(function(a,b) {b[1] - a[1]}).slice(0, 10);
  }

  this.getStageElements = function() {
    return {
      "players": allPlayers,
      "jewels": allJewels
    }
  }

  this.addPlayer = function(id) {
    var player = new Player(id);
    allPlayers[id] = player;
    placeItem(player);

    playersTotal += 1;
    playersCurrent += 1;

    if (playersCurrent > playersMax)
      playersMax = playersCurrent;

    this.emit("playerAdded", player);
  }

  this.removePlayer = function(id) {
    delete allPlayers[id];
    this.emit("playerRemoved", id);
  }

  this.addJewel = function() {
    var jewel = new Jewel(++jewelsTotal);
    allJewels[jewel.id] = jewel;
    placeItem(jewel);
    this.emit("jewelAdded", jewel);
  }

  this.removeJewel = function(id) {
    delete allJewels[id];
    this.emit("jewelRemoved", id);
  }

  this.setPlayerName = function(id, name) {
    allPlayers[id].name = name;
  }

  this.moveCharacter = function(id, direction) {
    var player = allPlayers[id];

    if (direction == "left") 
      player.x = Math.max(player.x - MOVINC, BOUNDS.x);
    else if (direction == "right")
      player.x = Math.min(player.x + MOVINC, BOUNDS.w);
    else if (direction == "up")
      player.y = Math.max(player.y - MOVINC, BOUNDS.y);
    else if (direction == "down") 
      player.y = Math.min(player.y + MOVINC, BOUNDS.h);

    this.emit("playerMoved", player);

    // Determine if user picked up a jewel
    for (var j in allJewels) {
      if (intersects(player, allJewels[j])) {
        player.jewelsCollected += 1;
        this.emit("playerScoreChanged", player);
        this.removeJewel(j);
        this.addJewel();
      }
    }
    
  }
}

util.inherits(Game, events.EventEmitter);
module.exports.Game = Game;

server.js

//
// Moonbase Mayhem
//

var nowjs = require("now");
var express = require ("express");
var moonbase = require("./game");

var app = express.createServer();
var everyone = nowjs.initialize(app);
var game = new moonbase.Game();

app.get("/", function(req, res) {
  res.send("Hello World!");
});

app.use(express.static(__dirname + "/public"));

nowjs.on("connect", function() {
  this.now.populateStage(game.getStageElements());
  this.now.updateScoreRoster(game.getScoreRoster());
  game.addPlayer(this.user.clientId);
  game.addJewel();
  console.log("Connect: " + this.user.clientId + " has joined");
});

nowjs.on("disconnect", function() {
  game.removePlayer(this.user.clientId);
  console.log("Disconnect: " + this.user.clientId + " has quit");
});

game.on("playerAdded", function(player) {
  everyone.now.addPlayer(player);
});

game.on("playerRemoved", function(id) {
  everyone.now.removePlayer(id);
});
 
game.on("jewelAdded", function(jewel) {
  everyone.now.addJewel(jewel);
});

game.on("jewelRemoved", function(id) {
  everyone.now.removeJewel(id);
});

game.on("playerMoved", function(player) {
  everyone.now.adjustStage(player.id, player.x, player.y);
});

game.on("playerScoreChanged", function(player) {
  if (player.name)
    everyone.now.updateScoreRoster(game.getScoreRoster());

  nowjs.getClient(player.id, function(e) {
    this.now.incrementScore(player.jewelsCollected);
  });
});

everyone.now.moveCharacter = function(dir) {
  game.moveCharacter(this.user.clientId, dir);
}

everyone.now.nameChanged = function(name) {
  game.setPlayerName(this.user.clientId, name);
  console.log("Name Change: " + this.user.clientId + " is " + name);
}

app.listen(8090);