fullToyExample.swift

import Foundation

enum ToyAction {
    case inert
    case smashIt
    case flipIt
    case rotateIt
    case flickIt
    case spinIt
    case passIt
    
    static let all: [ToyAction] = [.inert, .smashIt, .rotateIt, .flipIt, .flickIt, .spinIt, .passIt]
}

protocol ToyActionDelegate: class {
    func toyActionDidChange(_ toy: Toy, from oldAction: ToyAction, to newAction: ToyAction)
}

class Toy {
    weak var delegate: ToyActionDelegate?
    var name: String
    
    var currentAction: ToyAction = .inert {
        didSet {
            delegate?.toyActionDidChange(self, from: oldValue, to: currentAction)
        }
    }
    
    init(name: String) {
        self.name = name
    }
    
    func performAction(_ action: ToyAction) -> Bool {
        let wasCorrectAction = action == currentAction
        setNewRandomAction()
        return wasCorrectAction
    }
    
    func startNewGame() {
        currentAction = .inert
    }
    
    func play(_ rounds: Int) {
        for _ in 0..<rounds {
            setNewRandomAction()
        }
        
        startNewGame()
    }
    
    func setNewRandomAction() {
        let randomIndex = Int(arc4random_uniform(UInt32(ToyAction.all.count - 1))) + 1
        currentAction = ToyAction.all[randomIndex]
    }
}

class ToyActionPrinter: ToyActionDelegate {
    func toyActionDidChange(_ toy: Toy, from oldAction: ToyAction, to newAction: ToyAction) {
        print("\(toy.name) changed from \(oldAction) to \(newAction)")
    }
}

var toy = Toy(name: "SmashMe")
var printer = ToyActionPrinter()
toy.delegate = printer

toy.startNewGame()
toy.play(15)