public static StateTransition Replace(IAmATrafficLightState state)
{
if (state == null)
{
throw new ArgumentNullException("state");
}
return(new StateTransition(TransitionTypeOptions.Replace, state));
}
public TrafficLight(string trafficLightId, IAmATrafficLightState initialState)
{
if (string.IsNullOrWhiteSpace(trafficLightId))
{
throw new ArgumentNullException("Null/blank trafficLightId specified");
}
if (initialState == null)
{
throw new ArgumentNullException("initialState");
}
TrafficLightId = trafficLightId.Trim();
_states = new Stack <IAmATrafficLightState>();
_states.Push(initialState);
}
private StateTransition(TransitionTypeOptions transitionType, IAmATrafficLightState newState)
{
if (!Enum.IsDefined(typeof(TransitionTypeOptions), transitionType))
{
throw new ArgumentOutOfRangeException("transitionType");
}
if ((transitionType == TransitionTypeOptions.NoChange) || (transitionType == TransitionTypeOptions.Pop))
{
if (newState != null)
{
throw new ArgumentException("newState must be null if transitionType is NoChange or Pop");
}
}
else if (newState == null)
{
throw new ArgumentException("newState must be non-null if transitionType is Push or Replace");
}
TransitionType = transitionType;
NewState = newState;
}
