using UnityEngine;
using Ultrahaptics;

/// <summary>
/// Helper class to handle conversion between world space and Ultrahaptics device space.
/// </summary>
public class CoordinateSpaceConverter : MonoBehaviour
{
	// Expose this field to the Unity inspector so it can be set to
	// the transform that corresponds to the origin of the array (top-centre)
	[SerializeField]
	private Transform _arrayOrigin;

	/// <summary>
	/// Converts the given position vector from world space to device space.
	/// </summary>
	/// <param name="vector">The position vector in world space.</param>
	/// <returns>The equivalent position vector in device space.</returns>
	public Ultrahaptics.Vector3 WorldToDevicePosition(UnityEngine.Vector3 vector)
	{
		// Transform the world position to the local space of the array
		var localPosition = _arrayOrigin.InverseTransformPoint(vector);
		// Construct an Ultrahaptics Vector3
		// Note that the y and z coordinates are swapped as Ultrahaptics uses a coordinate system where the positive Y-axis is up
		var ultrahapticsPosition = new Ultrahaptics.Vector3(localPosition.x, localPosition.z, localPosition.y);
		return ultrahapticsPosition;
	}

	/// <summary>
	/// Converts the given direction vector from world space to device space.
	/// </summary>
	/// <param name="vector">The direction vector in world space.</param>
	/// <returns>The equivalent direction vector in device space.</returns>
	public Ultrahaptics.Vector3 WorldToDeviceDirection(UnityEngine.Vector3 vector)
	{
		// Transform the world direction to the local space of the array
		var localDirection = _arrayOrigin.InverseTransformDirection(vector);
		// Construct an Ultrahaptics Vector3
		// Note that the y and z coordinates are swapped as Ultrahaptics uses a coordinate system where the positive Y-axis is up
		var ultrahapticsDirection = new Ultrahaptics.Vector3(localDirection.x, localDirection.z, localDirection.y);
		return ultrahapticsDirection;
	}
}