using System;
using UnityEngine;

namespace RND
{
    [RequireComponent(typeof(RectTransform))]
    public class AnchorToTarget : MonoBehaviour
    {
        public enum UpdateMode { UPDATE, LATE_UPDATE, FIXED_UPDATE }

        [SerializeField] private UpdateMode _updateMode;
        [SerializeField] private Vector3 _anchorOffset;
        [SerializeField] private Vector3 _worldLocalOffset;
        
        private Transform _target;
        private RectTransform _rectTransform;

        private void Start()
        {
            _rectTransform = GetComponent<RectTransform>();
        }

        public void SetTarget(Transform target, bool needUpdate = true)
        {
            _target = target;

            if (needUpdate)
                UpdatePosition();
        }

        private void Update()
        {
            if (_updateMode != UpdateMode.UPDATE)
                return;

            UpdatePosition();
        }

        private void LateUpdate()
        {
            if (_updateMode != UpdateMode.LATE_UPDATE)
                return;

            UpdatePosition();
        }

        private void FixedUpdate()
        {
            if (_updateMode != UpdateMode.FIXED_UPDATE)
                return;

            UpdatePosition();
        }

        private void UpdatePosition()
        {
            if (_target == null)
                return;

            _rectTransform.anchoredPosition =
                UI.Canvas.WorldToCanvasPosition(_target.position + _target.rotation * _worldLocalOffset) +
                _anchorOffset;
        }
    }
}