extends Node2D
## One greybox arena, one screen (640x360), fixed camera. Draws its own
## floor and wall slabs; tracks kills and chemistry procs; conducts the
## authorship-loud chemistry feedback stack (canon: brief hitstop + the
## two tag hues meeting at the point of contact + a per-pair sting —
## no proc text, the light and the sting are the noun).

const CHEM_FX := preload("res://scripts/chemistry_fx.gd")

var kills: int = 0
var chem_procs: int = 0


func _ready() -> void:
	add_to_group("arena")
	$Spawner.grunt_spawned.connect(_on_grunt_spawned)
	$Mech.hull_changed.connect(_on_hull_changed)


func chemistry_proc(at: Vector2, axis: Vector2) -> void:
	chem_procs += 1
	var hand := get_tree().get_first_node_in_group("hand")
	if hand != null:
		hand.hitstop()
	var fx: Node2D = CHEM_FX.new()
	fx.position = at
	fx.axis = axis
	add_child(fx)
	$Sting.play()


func _on_grunt_spawned(grunt: Node) -> void:
	grunt.died.connect(func() -> void: kills += 1)


func _on_hull_changed(hull: float, hull_max: float) -> void:
	$HUD/HullFill.size.x = 118.0 * (hull / hull_max)


func _draw() -> void:
	draw_rect(Rect2(0, 0, 640, 360), Color(0.1, 0.11, 0.13))
	for x in range(0, 641, 32):
		draw_line(Vector2(x, 0), Vector2(x, 360), Color(0.13, 0.145, 0.17))
	for y in range(0, 361, 32):
		draw_line(Vector2(0, y), Vector2(640, y), Color(0.13, 0.145, 0.17))
	var wall := Color(0.3, 0.32, 0.36)
	draw_rect(Rect2(0, 0, 640, 16), wall)
	draw_rect(Rect2(0, 344, 640, 16), wall)
	draw_rect(Rect2(0, 0, 16, 360), wall)
	draw_rect(Rect2(624, 0, 16, 360), wall)