using UnityEngine;

namespace UI.Tracking
{
    /// <summary>
    /// Marks a GameObject as the source point for distance calculations in the tracking system.
    /// Typically attached to the player or camera. Only one should be active at a time.
    /// </summary>
    public class TrackingDistanceSource : MonoBehaviour
    {
        private static TrackingDistanceSource _instance;

        /// <summary>
        /// The currently active distance source (typically the player)
        /// </summary>
        public static TrackingDistanceSource Instance => _instance;

        /// <summary>
        /// The world position of this distance source
        /// </summary>
        public Vector3 WorldPosition => transform.position;

        private void OnEnable()
        {
            // Set as the active instance
            if (_instance != null && _instance != this)
            {
                Debug.LogWarning($"[TrackingDistanceSource] Multiple distance sources detected. Overwriting previous instance ({_instance.name}) with {name}");
            }
            _instance = this;
        }

        private void OnDisable()
        {
            // Clear instance if this was the active one
            if (_instance == this)
            {
                _instance = null;
            }
        }
    }
}