Character-code-sample/Characters/EnemyController.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AI;
using UnityEngine.UI;

[RequireComponent(typeof(NavMeshAgent), typeof(CharacterController))]
public class EnemyController : CharacterBase
{
    public enum AIState
    {
        Patrolling,
        Chasing
    }

    public AIState State;
    public List<Collider> PatrolPoints;
    private NavMeshAgent _agent;
    private Coroutine _attack;
    private Coroutine _currentAction;
    public LayerMask PlayerLayer;
    public Image PlayerDetectIndicator;

    protected override void Awake()
    {
        base.Awake();
        _agent = GetComponent<NavMeshAgent>();
        _agent.speed = Speed;
    }
    
    public bool IsAttacking()
    {
        return Display.GetCurrentAnimatorStateInfo(1).IsName("Attack");
    }

    public bool IsRecoil()
    {
        return Display.GetCurrentAnimatorStateInfo(0).IsName("Hit");
    }

    protected override void Update()
    {
        if (!IsAlive()) return;
        if (GameManager.Instance == null) return;

        CharacterBase target = GameManager.Instance.Player;
        if (_attack != null) return;
        if (target == null) return;

        if (State == AIState.Patrolling)
        {
            if (_currentAction == null)
            {
                Debug.Log("Patrollin");
                _currentAction = StartCoroutine(SetNewPatrolPoint());
            }
            else
            {
                var detectDistance = 5;
                var detectAngle = 45;
                var playerDir = target.transform.position - transform.position;

                if(Vector3.Angle(transform.forward, playerDir) <= detectAngle 
                    && Physics.Raycast(transform.position + Vector3.up * 0.5f, playerDir, detectDistance, PlayerLayer.value))
                {
                    PlayerDetectIndicator.fillAmount += Time.deltaTime;
                    if(PlayerDetectIndicator.fillAmount >= 1)
                    {
                        State = AIState.Chasing;
                    }
                }
                else
                {
                    PlayerDetectIndicator.fillAmount -= Time.deltaTime;
                }
            }
        }
        else if (State == AIState.Chasing)
        {
            _agent.SetDestination(target.transform.position);
            var dist = Vector3.Distance(transform.position, target.transform.position);

            if (dist < 2.5f)
            {
                _attack = StartCoroutine(Attack((target.transform.position - transform.position).normalized));
            }
        }
    }

    private IEnumerator Attack(Vector3 moveDirection)
    {
        _agent.enabled = false;
        _cc.enabled = true;

        Display.PlayState("Attack");
        float attackTime = 0;

        while(attackTime < 2)
        {
            _cc.SimpleMove(moveDirection * 5);
            attackTime += Time.deltaTime;
            yield return 0;
        }

        _cc.enabled = false;
        _agent.enabled = true;
        _attack = null;
    }

    private IEnumerator SetNewPatrolPoint()
    {
        var patrolPoint = PatrolPoints[Random.Range(0, PatrolPoints.Count)];
        var bounds = patrolPoint.bounds;
        var point = new Vector3(
            Random.Range(bounds.min.x, bounds.max.x),
            Random.Range(bounds.min.y, bounds.max.y),
            Random.Range(bounds.min.z, bounds.max.z)
        );
        _agent.SetDestination(point);
        float timeout = 10f;
        while (!_agent.isStopped && timeout > 0)
        {
            timeout -= Time.deltaTime;
            yield return 0;
        }
        yield return new WaitForSeconds(Random.Range(5f, 10f));
        _currentAction = null;
    }

    public override void TakeDamage(int dmg)
    {
        base.TakeDamage(dmg);
        if (IsAlive())
        {
            Display.PlayState("Hit");
        }
    }

    protected override void OnDeath()
    {
        Display.PlayState("Die");
        _cc.enabled = false;
    }
}