Raffle.scala

package tk.skuro.scala

object Raffle extends App {

  case class Attendee (name: String)

  type Attendees = Array[Attendee]
  case class RaffleState(participants: Attendees = new Array(0))

  val initialState = new RaffleState(new Array(0))
  mainMenu()

  def randomNumber(max: Int) = scala.util.Random.nextInt(max)

  def randomAttendee(attendees: Attendees, selector: (Int) => Int) = {
    val pick = selector(attendees.length)
    attendees(pick)
  }

  def addParticipant(state: RaffleState): Unit = {
    println()
    println("Enter the name of the participant:")
    val name = scala.io.StdIn.readLine()
    val participants = state.participants :+ new Attendee(name)
    mainMenu(new RaffleState(participants))
  }

  def raffle(state: RaffleState): Unit = {
    print("And the winner is .")
    Thread.sleep(200l)
    print("..")
    Thread.sleep(200l)
    print("..")
    Thread.sleep(200l)
    print("..")

    val luckyOne = randomAttendee(state.participants, randomNumber)
    println(s" ${luckyOne.name}!")
  }

  def mainMenu(state: RaffleState = new RaffleState(new Array(0))): Unit = {
    println("Choose one of the following:")
    println("1) Enter a participant")
    println("2) Raffle!")
    println()
    print("> ")
    val select = scala.io.StdIn.readLine()
    select match {
      case "1" => addParticipant(state)
      case "2" => raffle(state)
      case _ => {
        println("Try again dude!")
        mainMenu(state)
      }
    }
  }
}