class_name HudHeadingTape
extends HudInstrument

# Aircraft-style heading tape: a strip of compass ticks slides under a fixed
# centre marker, with cardinal letters so the player always knows which way
# they're facing. A dumb display fed by HUDController via set_heading.

const BG_COLOR := Color(0.05, 0.07, 0.11, 0.55)
const TICK_COLOR := Color(0.85, 0.92, 1.0, 0.9)
const MARKER_COLOR := Color(1.0, 0.8, 0.2)

# Degrees of heading visible across the full tape width.
const VISIBLE_RANGE := 90.0

const CARDINALS := {0: "N", 45: "NE", 90: "E", 135: "SE", 180: "S", 225: "SW", 270: "W", 315: "NW"}

var _target_heading := 0.0
var _heading := 0.0


func _ready() -> void:
	clip_contents = true


func set_heading(heading_deg: float) -> void:
	_target_heading = heading_deg


# Below this, the tape has visually settled — skip the redraw.
const REDRAW_EPSILON_DEG := 0.05

func _process(delta: float) -> void:
	var t := _smoothing_weight(delta)
	var new_heading := fmod(lerp_angle_deg(_heading, _target_heading, t) + 360.0, 360.0)
	var changed := absf(angle_delta_deg(_heading, new_heading)) > REDRAW_EPSILON_DEG
	_heading = new_heading
	if changed:
		queue_redraw()


func _draw() -> void:
	var font := ThemeDB.fallback_font
	var center_x := size.x / 2.0
	var px_per_deg := size.x / VISIBLE_RANGE

	draw_rect(Rect2(Vector2.ZERO, size), BG_COLOR)

	# Ticks every 5 degrees across the visible window, majors every 15.
	var first := ceili((_heading - VISIBLE_RANGE / 2.0) / 5.0) * 5
	for d in range(first, first + int(VISIBLE_RANGE) + 5, 5):
		var x := center_x + (float(d) - _heading) * px_per_deg
		var shown := wrapi(d, 0, 360)
		var major := shown % 15 == 0
		draw_line(Vector2(x, 0), Vector2(x, 10.0 if major else 5.0), TICK_COLOR, 1.0)
		if major:
			var text: String = CARDINALS.get(shown, str(shown))
			var text_size := font.get_string_size(text, HORIZONTAL_ALIGNMENT_CENTER, -1, 11)
			draw_string(font, Vector2(x - text_size.x / 2.0, 22.0), text,
				HORIZONTAL_ALIGNMENT_CENTER, -1, 11,
				MARKER_COLOR if CARDINALS.has(shown) else TICK_COLOR)

	# Fixed centre marker and numeric readout.
	draw_colored_polygon(PackedVector2Array([
		Vector2(center_x, 12.0), Vector2(center_x - 5, 2.0), Vector2(center_x + 5, 2.0),
	]), MARKER_COLOR)
	var reading := "%03d" % (roundi(_heading) % 360)
	var reading_size := font.get_string_size(reading, HORIZONTAL_ALIGNMENT_CENTER, -1, 13)
	draw_string(font, Vector2(center_x - reading_size.x / 2.0, size.y - 4.0), reading,
		HORIZONTAL_ALIGNMENT_CENTER, -1, 13, MARKER_COLOR)