@tool
extends Composer
class_name Spawner

@export var unit_type: PackedScene
@export var spawn_duration = 1.0
var _spawning_since = 0.0

@export var delivery = Vector2(100.0, 0.0):
	set(val):
		delivery = val
		_check_compose()
		
func _compose():
	$delivery.position = delivery
		
func _physics_process(delta):
	if Engine.is_editor_hint():
		return
		
	_spawning_since += delta
	if _spawning_since > spawn_duration:
		spawn()
		
func spawn():
	if unit_type:
		var unit := unit_type.instantiate()
		if unit is Unit:
			unit.position = delivery
			_spawning_since = min(0.0, _spawning_since - spawn_duration)
			# FIXME add to battlefield
			add_child(unit)