#nullable enable

using UnityEngine;

namespace ReplacedPerson.Runtime
{
    [ExecuteAlways]
    public sealed class ReplacedSafeArea : MonoBehaviour
    {
        private RectTransform? _rectTransform;
        private Rect _lastSafeArea;
        private Vector2Int _lastScreen;

        private void OnEnable() => Apply();
        private void OnRectTransformDimensionsChange() => Apply();

        private void Apply()
        {
            if (Screen.width <= 0 || Screen.height <= 0) return;
            var safe = Screen.safeArea;
            var screen = new Vector2Int(Screen.width, Screen.height);
            if (safe == _lastSafeArea && screen == _lastScreen) return;
            if (_rectTransform == null) _rectTransform = GetComponent<RectTransform>();
            if (_rectTransform == null) return;
            _rectTransform.anchorMin = new Vector2(safe.xMin / Screen.width, safe.yMin / Screen.height);
            _rectTransform.anchorMax = new Vector2(safe.xMax / Screen.width, safe.yMax / Screen.height);
            _rectTransform.offsetMin = Vector2.zero;
            _rectTransform.offsetMax = Vector2.zero;
            _lastSafeArea = safe;
            _lastScreen = screen;
        }
    }
}