twinStick/twinStickCrawler/Assets/Scripts/Creatures/Enemy/EnemyMove.cs

using System;
using UnityEngine;
using UnityEngine.AI;

namespace Creatures.Enemy
{
    public class EnemyMove : MonoBehaviour
    {
        public GameObject player;
        [SerializeField]
        private float playerDetectionRadius;
    
        private NavMeshAgent _meshAgent;

        private bool _playerFound = false;
        // Start is called once before the first execution of Update after the MonoBehaviour is created
        void Start()
        {
            _meshAgent = GetComponent<NavMeshAgent>();
        }

        // Update is called once per frame
        void Update()
        {
            Vector3 playerPos = player.transform.position;
            Debug.DrawRay(transform.position, (playerPos - transform.position).normalized * playerDetectionRadius, Color.red);
            
            if (!_playerFound && 
                Physics.Raycast(transform.position, (playerPos - transform.position).normalized, out RaycastHit hit, playerDetectionRadius, LayerMask.GetMask("Player")))
            {
                _playerFound = true;
            }


            if (_playerFound)
            {
                _meshAgent.SetDestination(playerPos);
            }
        }

        private void OnDrawGizmos()
        {
            Gizmos.color = Color.green;
            Gizmos.DrawWireSphere(transform.position, playerDetectionRadius);
        }
    }
}