extends Control

# #100: "an small alert on top right appear when a new wave is coming. No
# timer should be visible."
#
# The second half of that is a constraint on this file, not just a note.
# GameState deliberately offers no remaining-seconds accessor - only
# wave_warning_pulse(), which is a 0..1 throb - so there is no number here
# that could be rendered as a countdown even by accident. The urgency is
# carried by the pulse rate, which says "soon" without saying "in 4".

const GLOW: Color = Color(1.0, 0.45, 0.2)
const TEXT: String = "WAVE INCOMING"

var label: Label


func _ready() -> void:
	mouse_filter = Control.MOUSE_FILTER_IGNORE
	visible = false
	label = Label.new()
	label.text = TEXT
	label.mouse_filter = Control.MOUSE_FILTER_IGNORE
	label.add_theme_font_size_override("font_size", 22)
	label.add_theme_color_override("font_color", GLOW)
	label.add_theme_color_override("font_outline_color", Color(0.05, 0.01, 0.0, 0.95))
	label.add_theme_constant_override("outline_size", 3)
	label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	label.vertical_alignment = VERTICAL_ALIGNMENT_CENTER
	add_child(label)
	resized.connect(_layout)
	_layout()


func _layout() -> void:
	if label == null:
		return
	# Room on the left for the chevron _draw() puts there.
	label.position = Vector2(size.y, 0.0)
	label.size = Vector2(maxf(size.x - size.y, 0.0), size.y)


func _process(_delta: float) -> void:
	var incoming: bool = GameState.wave_is_incoming()
	if incoming != visible:
		visible = incoming
	if incoming:
		queue_redraw()


func _draw() -> void:
	if not visible:
		return
	var pulse: float = GameState.wave_warning_pulse()
	var alpha: float = 0.35 + 0.65 * pulse
	draw_rect(Rect2(Vector2.ZERO, size), Color(0.16, 0.04, 0.01, 0.62))
	NeonDraw.draw_glowing_path(self, PackedVector2Array([
		Vector2(0.0, 0.0), Vector2(size.x, 0.0), Vector2(size.x, size.y),
		Vector2(0.0, size.y), Vector2(0.0, 0.0),
	]), Color(GLOW, alpha), 0.9, 0.7)
	# A warning triangle, not a clock face.
	var centre: Vector2 = Vector2(size.y * 0.5, size.y * 0.5)
	var radius: float = size.y * 0.28
	NeonDraw.draw_glowing_polygon(self, PackedVector2Array([
		centre + Vector2(0.0, -radius),
		centre + Vector2(radius * 0.92, radius * 0.72),
		centre + Vector2(-radius * 0.92, radius * 0.72),
	]), Color(GLOW, alpha), 1.0)