extends Area2D
## KINETIC slug: damage plus knockback along its travel direction.
## Knockback is the load-bearing part — KINETIC is the one tag that
## touches the piloting layer, and the HEAT+KINETIC chemistry row
## (next slice) rides on impacts this weapon causes.

@export var speed := 420.0
@export var damage := 1.0
@export var knockback := 220.0
@export var lifetime := 0.8

var direction := Vector2.RIGHT


func _ready() -> void:
	add_to_group("projectiles")
	rotation = direction.angle()
	# Runtime load, not preload — resilient to a stale import cache.
	var spr := Sprite2D.new()
	spr.texture = load("res://assets/sprites_ph/slug_ph.png")
	add_child(spr)
	body_entered.connect(_on_body_entered)


func _physics_process(delta: float) -> void:
	position += direction * speed * delta
	lifetime -= delta
	if lifetime <= 0.0:
		queue_free()


func _on_body_entered(body: Node) -> void:
	if body.is_in_group("enemies"):
		body.hit(damage, direction * knockback)
	queue_free()