#if UNITY_5_3_OR_NEWER
using UnityEngine;

namespace RoboidControl.Unity {

	/// <summary>
	/// The Unity representation of a Roboid Control touch sensor
	/// </summary>
	public class TouchSensor : Thing {

		/// <summary>
		/// The core touch sensor
		/// </summary>
		public RoboidControl.TouchSensor coreSensor => base.core as RoboidControl.TouchSensor;

		/// <summary>
		/// Create the Unity representation of the touch sensor
		/// </summary>
		/// <param name="coreSensor">The core touch sensor</param>
		/// <returns>The Unity representation of the touch sensor</returns>
		/// This uses a 'TouchSensor' resource when available for the Unity representation.
		/// If this is not available, a default representation is created.
		public static TouchSensor Create(RoboidControl.TouchSensor coreSensor) {
			TouchSensor touchSensor;
			GameObject prefab = (GameObject)Resources.Load("TouchSensor");
			if (prefab != null) {
				// Use resource prefab when available
				GameObject gameObj = Instantiate(prefab);
				touchSensor = gameObj.GetComponent<TouchSensor>();
				touchSensor.Init(coreSensor);
			}
			else {
				// Default implementation
				GameObject gameObj = new(coreSensor.name);
				touchSensor = gameObj.AddComponent<TouchSensor>();
				touchSensor.Init(coreSensor);

				Rigidbody rb = gameObj.AddComponent<Rigidbody>();
				rb.isKinematic = true;

				SphereCollider collider = gameObj.AddComponent<SphereCollider>();
				collider.radius = 0.01f;
				collider.isTrigger = true;
			}
			return touchSensor;
		}

		/// <summary>
		/// Handle touch trigger collider enter event
		/// </summary>
		/// <param name="other">The collider which entered our trigger collider</param>
		private void OnTriggerEnter(Collider other) {
			// Don't detect trigger colliders
			if (other.isTrigger)
				return;			
			// Don't touch yourself
			if (this.transform.root == other.transform.root)
				return;			

			this.coreSensor.touchedSomething = true;
			this.core.updateQueue.Enqueue(new RoboidControl.Thing.CoreEvent(BinaryMsg.Id));
		}
		/// <summary>
		/// Handl touch trigger collider exit event
		/// </summary>
		/// <param name="other">The collider which exited our trigger collider </param>
		private void OnTriggerExit(Collider other) {
			if (other.isTrigger)
				return;

			this.coreSensor.touchedSomething = false;
		}
	}
}
#endif