chat_with_actors.scala

import scala.actors.Actor
import scala.actors._
import scala.collection.mutable.Map
import java.io._
import java.net.{InetAddress,ServerSocket,Socket,SocketException}

class Coordinator extends Actor {

  var clients    = Map[String, Client]()
  var numClients = 0

  def pushClient(client:Client) {
    clients(client.id) = client
    numClients += 1
    println("Pushed client " + client.id + " Total connected: " + numClients)
  }

  def removeClient(client:Client) {
    clients.remove(client.id)
    numClients -= 1
    println("Removed client " + client.id + " Total connected: " + numClients)
  }

  def handleMsg(data:Map[String, String]) {
    val clientId = data("id")
    clients.keys.foreach( k => {
      if (k != clientId)
        clients(k) ! data
    })
  }

  def act {
    loop {
      react {
        case data:Map[String, String] => handleMsg(data)
        case "_" => {}
      }
    }
  }
}

class PortListener(val port:Int, val coordinator:Coordinator) extends Actor {
  def act {

    println("PortListener: listening on " + port)
    val listener = new ServerSocket(port)

    loop {
      val client = new Client(listener.accept(), coordinator)
      client.start
      coordinator.pushClient(client)
    }
  }
}

class Client(val socket:Socket, val chatCoord:Coordinator) extends Actor {

  var id   = scala.util.Random.nextInt(1000000).toString
  var name = "anon" + scala.util.Random.nextInt(1000000).toString
  val out  = new PrintWriter(socket.getOutputStream(), true)
  val in   = new BufferedReader( new InputStreamReader(socket.getInputStream()))
  val col  = 1 + scala.util.Random.nextInt(7)

  def log(msg:String) {
    println("Client " + id + ": " + msg)
  }

  def write(msg:String) {
    out.println(msg); out.flush
  }

  def handleMesg(data:Map[String, String]) {
    val startCode = "\033[3" + data("col") + ";1m"
    write(startCode + ">> "  + data("id") + ":\033[0m " + data("msg"))
  }

  def act {
    write("\033[37;1mConnected to chatserver ... There are " + chatCoord.numClients + " connected clients\033[0m")
    loop {

      if (in.ready) {
        val msg = in.readLine
        log("Socket read " + msg)

        if (msg.startsWith("/name"))
          name = msg.split(" ").last
        else
          chatCoord ! Map(
          "id"   -> id,
          "name" -> name
          "msg"  -> msg,
          "col"  -> col.toString
        )
      }

      reactWithin(100) {
        case data:Map[String, String] => handleMesg(data)
        case _     =>  {}
      }
    }
  }
}

println("STARTING")

val chatCoord = new Coordinator
val listener  = new PortListener(8080, chatCoord)

chatCoord.start
listener.start