#if ! (UNITY_DASHBOARD_WIDGET || UNITY_WEBPLAYER || UNITY_WII || UNITY_WIIU || UNITY_NACL || UNITY_FLASH || UNITY_BLACKBERRY) // Disable under unsupported platforms.
//////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2014 Audiokinetic Inc. / All Rights Reserved
//
//////////////////////////////////////////////////////////////////////

public abstract class AkObstructionOcclusion : UnityEngine.MonoBehaviour
{
	private readonly System.Collections.Generic.List<AkAudioListener> listenersToRemove =
		new System.Collections.Generic.List<AkAudioListener>();

	protected readonly System.Collections.Generic.List<AkAudioListener> currentListenerList = new System.Collections.Generic.List<AkAudioListener>();

	private readonly System.Collections.Generic.Dictionary<AkAudioListener, ObstructionOcclusionValue>
		ObstructionOcclusionValues = new System.Collections.Generic.Dictionary<AkAudioListener, ObstructionOcclusionValue>();

	protected float fadeRate;

	[UnityEngine.Tooltip("Fade time in seconds")]
	/// The number of seconds for fade ins and fade outs.
	public float fadeTime = 0.5f;

	[UnityEngine.Tooltip("Layers of obstructers/occluders")]
	/// Indicates which layers act as obstructers/occluders.
	public UnityEngine.LayerMask LayerMask = -1;

	[UnityEngine.Tooltip("Maximum distance to perform the obstruction/occlusion. Negative values mean infinite")]
	/// The maximum distance at which to perform obstruction/occlusion. A negative value will be interpreted as inifinite distance.
	public float maxDistance = -1.0f;

	[UnityEngine.Tooltip("The number of seconds between raycasts")]
	/// The number of seconds between obstruction/occlusion checks.
	public float refreshInterval = 1;

	private float refreshTime;

	protected void InitIntervalsAndFadeRates()
	{
		refreshTime = UnityEngine.Random.Range(0.0f, refreshInterval);
		fadeRate = 1 / fadeTime;
	}

	protected abstract void UpdateCurrentListenerList();

	private void UpdateObstructionOcclusionValues()
	{
		// add new listeners
		for (var i = 0; i < currentListenerList.Count; ++i)
		{
			if (!ObstructionOcclusionValues.ContainsKey(currentListenerList[i]))
				ObstructionOcclusionValues.Add(currentListenerList[i], new ObstructionOcclusionValue());
		}

		// remove listeners
		foreach (var ObsOccPair in ObstructionOcclusionValues)
		{
			if (!currentListenerList.Contains(ObsOccPair.Key))
				listenersToRemove.Add(ObsOccPair.Key);
		}

		for (var i = 0; i < listenersToRemove.Count; ++i)
			ObstructionOcclusionValues.Remove(listenersToRemove[i]);

		listenersToRemove.Clear();
	}

	private void CastRays()
	{
		if (refreshTime > refreshInterval)
		{
			refreshTime -= refreshInterval;

			foreach (var ObsOccPair in ObstructionOcclusionValues)
			{
				var listener = ObsOccPair.Key;
				var ObsOccValue = ObsOccPair.Value;

				var difference = listener.transform.position - transform.position;
				var magnitude = difference.magnitude;

				if (maxDistance > 0 && magnitude > maxDistance)
					ObsOccValue.targetValue = ObsOccValue.currentValue;
				else
				{
					ObsOccValue.targetValue =
						UnityEngine.Physics.Raycast(transform.position, difference / magnitude, magnitude, LayerMask.value) ? 1.0f : 0.0f;
				}
			}
		}

		refreshTime += UnityEngine.Time.deltaTime;
	}

	protected abstract void SetObstructionOcclusion(
		System.Collections.Generic.KeyValuePair<AkAudioListener, ObstructionOcclusionValue> ObsOccPair);

	private void Update()
	{
		currentListenerList.Clear();
		UpdateCurrentListenerList();
		UpdateObstructionOcclusionValues();

		CastRays();

		foreach (var ObsOccPair in ObstructionOcclusionValues)
		{
			if (ObsOccPair.Value.Update(fadeRate))
				SetObstructionOcclusion(ObsOccPair);
		}
	}

	protected class ObstructionOcclusionValue
	{
		public float currentValue;
		public float targetValue;

		public bool Update(float fadeRate)
		{
			if (UnityEngine.Mathf.Approximately(targetValue, currentValue))
				return false;

			currentValue += fadeRate * UnityEngine.Mathf.Sign(targetValue - currentValue) * UnityEngine.Time.deltaTime;
			currentValue = UnityEngine.Mathf.Clamp(currentValue, 0.0f, 1.0f);
			return true;
		}
	}
}
#endif // #if ! (UNITY_DASHBOARD_WIDGET || UNITY_WEBPLAYER || UNITY_WII || UNITY_WIIU || UNITY_NACL || UNITY_FLASH || UNITY_BLACKBERRY) // Disable under unsupported platforms.