enemy ai tutorial

extends CharacterBody3D

enum {
    SLEEP,
    AWAKE,
    CHASE,
    ATTACK,
    WAIT
}

var CURRENT_STATE = SLEEP

var cooldown = []
var stats = {
    "max_health": 100,
    "health": 100,
    "default_speed": 4.0,
    "speed": 0.0,
    "attack_speed": 20.0
}


@onready var agent = $NavigationAgent3D
@onready var plr = get_node(PLAYER_PATH)
@onready var anim = $Anim

func _ready():
    stats["speed"] = stats["default_speed"]
    $Indicator.visible = false

func _physics_process(delta):
    if CURRENT_STATE == CHASE or CURRENT_STATE == ATTACK:
        var next_location = agent.get_next_path_position()
        var final_velocity = (next_location - global_transform.origin).normalized() * stats["speed"]

        agent.set_velocity(final_velocity)

    if CURRENT_STATE == SLEEP: $Sight/Raycasts.look_at(plr.position, Vector3.UP);
    state_handler()

func awaken():
    if cooldown.has("awake") == true: return
    cooldown.append("awake")

    $Indicator.visible = true
    anim.play("Shock")

    await get_tree().create_timer(0.6).timeout

    $Indicator.visible = false
    CURRENT_STATE = CHASE

func attack():
    cooldown.append("attack_cd")
    anim.play("Attack")
    stats["speed"] = stats["attack_speed"]

    await get_tree().create_timer(0.4).timeout

    CURRENT_STATE = WAIT
    stats["speed"] = stats["default_speed"]

    await get_tree().create_timer(0.4).timeout

    cooldown.erase("attack_cd")
    CURRENT_STATE = CHASE

func state_handler():
    match CURRENT_STATE:
        SLEEP:
            stats["speed"] = 0
            anim.play("Sleep")

            if check_in_range() == true:
                CURRENT_STATE = AWAKE

        AWAKE:
            awaken()

        CHASE:
            stats["speed"] = stats["default_speed"]
            anim.play("Run")
            agent.set_target_position(plr.position)

        WAIT:
            anim.play("Shock")
            stats["speed"] = 0

        ATTACK:
            if not cooldown.has("attack_cd"):
                attack()

func check_in_range():
    for ray in $Sight/Raycasts.get_children():
        if ray.is_colliding():
            var obj = ray.get_collider()

            if obj.name == "PLAYER NAME OR GROUP HERE":
                return true
            else:
                return false

# In range
func _on_navigation_agent_3d_target_reached():
    CURRENT_STATE = ATTACK

func set_float():
    if CURRENT_STATE == ATTACK: return 1
    else: return 0.5

func _on_navigation_agent_3d_velocity_computed(safe_velocity):
    velocity = velocity.move_toward(safe_velocity, set_float())
    move_and_slide()