﻿// The MIT License (MIT)
// 
// Copyright (c) 2014-2017, Institute for Software & Systems Engineering
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// THE SOFTWARE.

namespace SafetySharp.CaseStudies.HeightControl.Modeling.Controllers
{
	using SafetySharp.Modeling;
	using Sensors;
	using Vehicles;

	/// <summary>
	///   Represents the original design of the end-control.
	/// </summary>
	public class EndControlLightBarrier : EndControl
	{
		/// <summary>
		///   The sensor that is used to detect overheight vehicles in the end-control area on the right lane.
		/// </summary>
		[Subcomponent]
		public readonly VehicleDetector RightLaneDetector = new SmallLightBarrier(Model.EndControlPosition, Lane.Right);

		/// <summary>
		///   The number of high vehicles currently in the main-control area.
		/// </summary>
		[Range(0, 5, OverflowBehavior.Clamp)]
		private int _count;

		/// <summary>
		///   Gets the number of vehicles that entered the area in front of the end control during the current system step.
		/// </summary>
		public override void VehicleEntering()
		{
			_count++;
			Timer.Start();
		}

		/// <summary>
		///   Updates the internal state of the component.
		/// </summary>
		public override void Update()
		{
			Update(Timer, LeftDetector, RightLaneDetector);

			if (_count > 0 && LeftDetector.IsVehicleDetected)
				CloseTunnel();

			if (RightLaneDetector.IsVehicleDetected)
				_count--;

			if (Timer.HasElapsed)
				_count = 0;
			else if (_count == 0)
				Timer.Stop();
		}
	}
}