public void ItTurnLightRedAtCrossingStation()
{
//Given
var signalS0 = new Signal() {Name = "S0", Light = Light.GREEN};
var track = new Track(signalS0);
//When
track.TrainCrosses(signalS0);
//Then
Assert.AreEqual(Light.RED, signalS0.Light);
}
public void ItTurnLightYellowAtLastStation()
{
//Given
var signalS0 = new Signal() { Name = "S0", Light = Light.RED };
var signalS1 = new Signal() { Name = "S1", Light = Light.GREEN };
var track = new Track(signalS0, signalS1);
//When
track.TrainCrosses(signalS1);
//Then
Assert.AreEqual(Light.YELLOW, signalS0.Light);
}
public void ItTurnLightDoubleYellowTwoStationBack()
{
//Given
var signalS0 = new Signal() { Name = "S0", Light = Light.YELLOW };
var signalS1 = new Signal() { Name = "S1", Light = Light.RED };
var signalS2 = new Signal() { Name = "S2", Light = Light.GREEN };
var track = new Track(signalS0, signalS1, signalS2);
//When
track.TrainCrosses(signalS2);
//Then
Assert.AreEqual(Light.DOUBLE_YELLOW, signalS0.Light);
}
private List<Signal> GetTailingSignalsFrom(Signal currentSignal)
{
var endIndex = Signals.IndexOf(currentSignal);
var startIndex = endIndex - MIN_BLOCKS >= 0 ? endIndex - MIN_BLOCKS : 0;
return Signals.GetRange(startIndex, endIndex + 1);
}
public void TrainCrosses(Signal currentSignal)
{
GetTailingSignalsFrom(currentSignal).ForEach(signal =>
signal.ToggleLight());
}
