CourierOld/Game/CourierOld/Assets/Code/Gameplay/Enemies/EnemySpawner.cs

using Code.Gameplay.Player;
using Cysharp.Threading.Tasks;
using Reflex.Attributes;
using Reflex.Core;
using Reflex.Injectors;
using UnityEngine;

namespace Code.Gameplay.Enemies
{
    public class EnemySpawner : MonoBehaviour
    {
        [SerializeField] private EnemyType spawnerType;
        [SerializeField] private float spawnRadius = 40f;
        [SerializeField] private float despawnRadius = 50f;

        [Inject] private IPlayerProvider _playerProvider;
        [Inject] private IEnemyFactory _enemyFactory;

        private BaseEnemy _spawnedEnemy;
        private bool _isSpawning;
        private bool _isPlayerInRange;

        private void Awake()
        {
            if (_playerProvider == null || _enemyFactory == null)
            {
                AttributeInjector.Inject(this, Container.ProjectContainer);
            }
        }

        private void Update()
        {
            if (!_playerProvider?.Character)
                return;

            var distanceToPlayer = Vector3.Distance(transform.position, _playerProvider.Character.transform.position);

            var wasInRange = _isPlayerInRange;
            _isPlayerInRange = distanceToPlayer <= spawnRadius;

            switch (_isPlayerInRange)
            {
                case true when !_spawnedEnemy && !_isSpawning && !wasInRange:
                    Spawn().Forget();
                    break;
                case false when _spawnedEnemy && distanceToPlayer > despawnRadius:
                    Despawn();
                    break;
            }
        }

        private async UniTask Spawn()
        {
            if (_spawnedEnemy || _isSpawning) return;

            _isSpawning = true;
            var enemy = await _enemyFactory.CreateEnemy(
                spawnerType,
                transform.position,
                transform.rotation
            );
                
            _spawnedEnemy = enemy;
            _isSpawning = false;
        }

        private void Despawn()
        {
            if (_spawnedEnemy == null) return;

            _enemyFactory.ReleaseEnemy(_spawnedEnemy);
            _spawnedEnemy = null;
        }

        private void OnDrawGizmosSelected()
        {
            Gizmos.color = new Color(0, 1, 0, 0.5f);
            Gizmos.DrawSphere(transform.position, spawnRadius);

            Gizmos.color = new Color(1, 0, 0, 0.2f);
            Gizmos.DrawSphere(transform.position, despawnRadius);
        }
    }
}