class EnemyModel
{
	public ReactiveProperty<long> CurrentHp { get; private set; }
	public ReactiveProperty<bool> IsDed { get; private set; }

	public EnemyModel(int initialHp)
	{
		CurrentHp = new ReactiveProperty<long>(initialHp);
		IsDead = CurrentHp.Select(x => x <= 0).ToReactiveProperty();
	}
}

class ReactivePresenter : MonoBehaviour
{
	// Inject these dependencies in the Inspector.
	public Button MyButton;
	public Toggle MyToggle;

	// State-change events from model.
	Enemy enemy = new Enemy(1000);

	void SubscribeToModel()
	{
		enemy.CurrentHp.SubscribeToText(MyText);
		enemy.IsDead.Where(isDead => isDead).Subscribe(HandleIsDeadChange);
	}

	void HandleIsDeadChange()
	{
		MyToggle.interactable = false;
		MyButton.interactable = false;
	}

	void SubscribeToUI()
	{
		MyButton.OnClickAsObservable().Subscribe(HandleButtonClick);
		MyToggle.OnValueChangedAsObservable().SubscribeToInteractable(MyButton);
	}

	void HandleButtonClick()
	{
		enemy.CurrentHp.Value -= 99;
	}

	void Start()
	{
		SubscribeToModel();
		SubscribeToUI();
	}
}