Pattern Matching Unpack

  abstract class Dickmacher
  case class Beverage (name: String, cal: Int) extends Dickmacher
  case class Food (name: String, cal: Int) extends Dickmacher
  case class Meal (name: String, food: Food, drink: Beverage) extends Dickmacher
  case class Combo (starter: Dickmacher, main: Dickmacher) extends Dickmacher

  def unpack(food: Dickmacher) : List[Dickmacher] = food match {
    case a: Beverage => a :: Nil
    case b: Food => b :: Nil
    case Meal(_, b , a) => a :: b :: Nil
    case Combo(a, b) => unpack(a) ::: unpack(b)
    case _ => Nil
  }
  
  val coke = Beverage("Cola Light", 50)
  val burger = Food("Big Mac", 400)
  
  
  val cokeLight = Beverage("Cola", 100)
  val wannaBeBurger = Food("Veggie Mac", 50)
  

  val cokeCombo = Combo(coke, cokeLight)
  println(unpack(cokeCombo))
  
  
  val burgerCombo = Combo(burger, wannaBeBurger)
  println(unpack(burgerCombo))
  
  
  val monsterCombo = Combo(Combo(burgerCombo, cokeCombo), Food("Nachspeise", 600));
  println(unpack(monsterCombo))