using System.Collections.Generic;
using UnityEngine;
using Unheimlich.Features.Dialogue.UI;

namespace Unheimlich.Features.Hallucination
{
    /// <summary>
    /// Static registry that FloatingLabel instances self-register into on OnEnable/OnDisable.
    /// Lets HallucinationManager iterate active labels in a radius without any FindObjectsOfType.
    /// </summary>
    public static class HallucinationLabelRegistry
    {
        private static readonly HashSet<FloatingLabel> _labels = new();

        public static void Register(FloatingLabel label)   => _labels.Add(label);
        public static void Unregister(FloatingLabel label) => _labels.Remove(label);

        /// <summary>
        /// Returns all registered labels whose transform is within <paramref name="radius"/>
        /// of <paramref name="center"/>. Results are written into <paramref name="results"/>
        /// (which is cleared first) to avoid allocations per call.
        /// </summary>
        public static void GetLabelsInRadius(Vector3 center, float radius, List<FloatingLabel> results)
        {
            results.Clear();
            float sqrRadius = radius * radius;
            foreach (FloatingLabel label in _labels)
            {
                if (label == null) continue;
                if ((label.transform.position - center).sqrMagnitude <= sqrRadius)
                    results.Add(label);
            }
        }
    }
}