// EnemyStateMachine.cs
public interface IEnemyState
{
    void Enter();
    void Update();
    void Exit();
}

public class EnemyStateMachine
{
    private IEnemyState currentState;

    public void ChangeState(IEnemyState newState)
    {
        currentState?.Exit();
        currentState = newState;
        currentState?.Enter();
    }

    public void Update()
    {
        currentState?.Update();
    }
}
--------------------------------------------------------------------------------------------------------------------------------
// BaseEnemy.cs
using UnityEngine;
using UnityEngine.AI;

[RequireComponent(typeof(NavMeshAgent))]
public abstract class BaseEnemy : MonoBehaviour
{
    [Header("BASE VALUES")]
    public float maxHealth;
    public float movementSpeed;
    public float attackRange;
    public float attackCooldown;
    public float damage;

    protected float currentHealth;
    protected NavMeshAgent agent;
    protected Transform player;
    protected Animator animator;
    protected EnemyStateMachine stateMachine;
    protected WaveManager waveManager;

    protected virtual void Awake()
    {
        agent = GetComponent<NavMeshAgent>();
        animator = GetComponentInChildren<Animator>();
        waveManager = GetComponentInParent<Wavemanager>();
        stateMachine = new EnemyStateMachine();
        currentHealth = maxHealth;
    }

    protected virtual void Start()
    {
        player = waveManager.player;
        agent.speed = movementSpeed;
    }

    protected virtual void Update()
    {
        stateMachine.Update();
    }

    public virtual void TakeDamage(float amount)
    {
        currentHealth -= amount;
        if (currentHealth <= 0)
        {
            Die();
        }
    }

    protected virtual void Die()
    {
        agent.isStopped = true;
        animator.SetTrigger("Die");
        Destroy(gameObject, 3f);
    }

    public bool IsPlayerInRange(float range)
    {
        if (!player) return false;
        return Vector3.Distance(transform.position, player.position) <= range;
    }

    public void FacePlayer()
    {
        if (!player) return;
        Vector3 dir = (player.position - transform.position).normalized;
        dir.y = 0;
        if (dir != Vector3.zero)
        {
            transform.rotation = Quaternion.Slerp(transform.rotation, Quaternion.LookRotation(dir), Time.deltaTime * 10f);
        }
    }

    public Transform GetPlayerTransform() => player;
    public NavMeshAgent GetAgent() => agent;
    public Animator GetAnimator() => animator;
    public EnemyStateMachine GetStateMachine() => stateMachine;
}
--------------------------------------------------------------------------------------------------------------------------------
// MeleeEnemy.cs
public class MeleeEnemy : BaseEnemy
{
    private IdleState idleState;
    private FollowState followState;
    private MeleeAttackState attackState;

    protected override void Start()
    {
        base.Start();

        idleState = new IdleState(this);
        followState = new FollowState(this);
        attackState = new MeleeAttackState(this);

        stateMachine.ChangeState(followState);
    }

    public IdleState GetIdleState() => idleState;
    public FollowState GetFollowState() => followState;
    public MeleeAttackState GetAttackState() => attackState;
}
--------------------------------------------------------------------------------------------------------------------------------
// IdleState.cs
public class IdleState : IEnemyState
{
    private MeleeEnemy enemy;

    public IdleState(MeleeEnemy e) { enemy = e; }

    public void Enter()
    {
        enemy.GetAgent().isStopped = true;
        enemy.GetAnimator().SetBool("isIdle", true);
    }

    public void Update()
    {
        if (enemy.IsPlayerInRange(enemy.attackRange))
        {
            enemy.GetStateMachine().ChangeState(enemy.GetAttackState());
        }
        else
        {
            enemy.GetStateMachine().ChangeState(enemy.GetFollowState());
        }
    }

    public void Exit()
    {
        enemy.GetAnimator().SetBool("isIdle", false);
    }
}
--------------------------------------------------------------------------------------------------------------------------------
// FollowState.cs
public class FollowState : IEnemyState
{
    private MeleeEnemy enemy;

    public FollowState(MeleeEnemy e) { enemy = e; }

    public void Enter()
    {
        enemy.GetAgent().isStopped = false;
        enemy.GetAnimator().SetBool("isRunning", true);
    }

    public void Update()
    {
        enemy.GetAgent().SetDestination(enemy.GetPlayerTransform().position);
        enemy.FacePlayer();

        if (enemy.IsPlayerInRange(enemy.attackRange))
        {
            enemy.GetStateMachine().ChangeState(enemy.GetAttackState());
        }
    }

    public void Exit()
    {
        enemy.GetAnimator().SetBool("isRunning", false);
    }
}
--------------------------------------------------------------------------------------------------------------------------------
// MeleeAttackState.cs
using UnityEngine;

public class MeleeAttackState : IEnemyState
{
    private MeleeEnemy enemy;
    private float attackCooldownTimer;

    public MeleeAttackState(MeleeEnemy enemy)
    {
        enemy = enemy;
    }

    public void Enter()
    {
        enemy.GetAgent().isStopped = true;
        enemy.GetAnimator().SetBool("isAttacking", true);
        attackCooldownTimer = 0f;
    }

    public void Update()
    {
        enemy.FacePlayer();

        attackCooldownTimer += Time.deltaTime;

        if (attackCooldownTimer >= enemy.attackCooldown)
        {
            enemy.GetAnimator().SetTrigger("Attack");
            attackCooldownTimer = 0f;
        }

        if (!enemy.IsPlayerInRange(enemy.attackRange))
        {
            enemy.GetStateMachine().ChangeState(enemy.GetFollowState());
        }
    }

    public void Exit()
    {
        enemy.GetAnimator().SetBool("isAttacking", false);
    }
}