class Board(var layout: Array[Char]) {
  if (!layout.mkString.matches("[xo ]{9}")) {
    println("Invalid layout")
    layout = "         ".toArray
  }

  def this() {
    this("         ".toArray)
  }

  def show {
    println("\n --- ")
    println("|" + layout.mkString.substring(0,3) + "|")
    println("|" + layout.mkString.substring(3,6) + "|")
    println("|" + layout.mkString.substring(6,9) + "|")
    println(" --- ")
  }

  def status:Char = {
    // Horizontal
    if (layout(0) == layout(1) && layout(1) == layout(2))
      return layout(0)
    else if (layout(3) == layout(4) && layout(4) == layout(5))
      return layout(3)
    else if (layout(6) == layout(7) && layout(7) == layout(8))
      return layout(7)

    // Vertical
    else if (layout(0) == layout(3) && layout(3) == layout(6))
      return layout(0)
    else if (layout(1) == layout(4) && layout(4) == layout(7))
      return layout(1)
    else if (layout(2) == layout(5) && layout(5) == layout(8))
      return layout(2)

    // Diagonal
    else if (layout(0) == layout(4) && layout(4) == layout(8))
      return layout(0)
    else if (layout(2) == layout(4) && layout(4) == layout(6))
      return layout(2)

    return if (layout.contains(' ')) ' ' else 't'
  }

  def play {
    var st = status
    var player = 'x'
    var input = ""

    reset
    show
    while (st == ' ') {
      print("Player " + player + "> ")
      input = readLine
      if (input.matches("[0-8]") && layout(input.toInt) == ' ') {
        layout(input.toInt) = player
        show
        player = if (player == 'x') 'o' else 'x'
      }
      st = status
    }
    if (status == 't')
      println("There is a tie!")
    else
      println("The winner is " + status + "!")
  }

  def reset {
    layout = "         ".toArray
  }
}

var playBoard = new Board
playBoard.play