/* Mediator Design Pattern */

var Participant = function(name) {
  this.name = name;
  this.chatroom = null;
};

Participant.prototype = {
  send: function(message, to) {
    this.chatroom.send(message, this, to);
  },
  receive: function(message, from) {
    console.log(from.name + " to " + this.name + ": " + message);
  }
};

var Chatroom = function() {
  var participants = {};

  return {
    register: function(participant) {
      participants[participant.name] = participant;
      participant.chatroom = this;
    },

    send: function(message, from, to) {
      if (to) {
        // single message
        to.receive(message, from);
      } else {
        // broadcast message
        for (key in participants) {
          if (participants[key] !== from) {
            participants[key].receive(message, from);
          }
        }
      }
    }
  };
};

var beau = new Participant("Beau");
var quincy = new Participant("Quincy");
var rafael = new Participant("Rafael");
var berkeley = new Participant("Berkeley");
var evaristo = new Participant("Evaristo");

var chatroom = new Chatroom();
chatroom.register(beau);
chatroom.register(quincy);
chatroom.register(rafael);
chatroom.register(berkeley);
chatroom.register(evaristo);

quincy.send("How's it going?");
beau.send("The YouTube channel is up to 1 million subscribers!", quincy);
rafael.send("The FCC wiki is more popular than Wikipedia!", quincy);
evaristo.send("98% of our graduates got their dream job!", quincy);
berkeley.send("The government forked our repo and is now using it to create world peace!", quincy);