extends Area2D

signal hit

export var speed = 400 # pixel / sec
var screen
var target = Vector2()
var target_reached = true

func spawn(atPos):
	position = atPos
	show()
	$CollisionShape2D.disabled = false

func die():
	hide()

func _ready():
	hide()
	screen = get_viewport_rect()

func _process(delta):
	var velocity = get_velocity_from_action()
	if velocity == Vector2.ZERO :
		velocity = get_velocity_from_target(delta)

	if velocity.length() > 0:
		velocity = velocity.normalized() * speed
		$AnimatedSprite.play()
	else:
		$AnimatedSprite.stop()
	
	position += velocity * delta
	
	position.x = clamp(position.x, 0, screen.size.x)
	position.y = clamp(position.y, 0, screen.size.y)
	
	if velocity.x != 0:
		$AnimatedSprite.animation = "right"
		$AnimatedSprite.flip_v = false
		$AnimatedSprite.flip_h = velocity.x < 0
	elif velocity.y != 0:
		$AnimatedSprite.animation = "up"
		$AnimatedSprite.flip_v = velocity.y > 0


func _input(event):
	if event is InputEventMouseButton or event is InputEventMouseMotion :
		target = event.position
		target_reached = false


func _on_Player_body_entered(_body):
	die()
	emit_signal("hit")
	$CollisionShape2D.set_deferred("disabled", true)

func get_velocity_from_action() -> Vector2:
	var velocity = Vector2()

	if Input.is_action_pressed("ui_right"):
		velocity.x += 1
	if Input.is_action_pressed("ui_left"):
		velocity.x -= 1
	if Input.is_action_pressed("ui_down"):
		velocity.y += 1
	if Input.is_action_pressed("ui_up"):
		velocity.y -= 1

	return velocity;

func get_velocity_from_target(delta):
	if target_reached :
		return Vector2.ZERO

	var path = target - position

	if path.length_squared() < speed * speed * delta * delta :
		target_reached = true
		return Vector2.ZERO

	return path