extends Control

@export var day_night_cycle: Node

const SIZE_DIAL := 60.0
const RING_RADIUS := 24.0
const RING_THICKNESS := 4.0
const GLOW_RADIUS := 2.5

const COLOR_NIGHT := Color(0.12, 0.16, 0.42, 1)
const COLOR_DAWN := Color(0.95, 0.5, 0.2, 1)
const COLOR_DAY := Color(1, 0.84, 0.38, 1)
const COLOR_DUSK := Color(0.9, 0.35, 0.2, 1)
const COLOR_BG := Color(0.06, 0.06, 0.08, 0.65)

var _last_fraction := -1.0
var _last_color := Color.TRANSPARENT


func _process(_delta: float) -> void:
	var fraction := _cycle_fraction()
	if not is_equal_approx(fraction, _last_fraction):
		_last_fraction = fraction
		queue_redraw()


func _draw() -> void:
	var center := Vector2(SIZE_DIAL / 2.0, SIZE_DIAL / 2.0)
	var fraction := _last_fraction
	if fraction < 0.0:
		fraction = _cycle_fraction()
		_last_fraction = fraction

	var time_color := _time_color(fraction)

	draw_circle(center, RING_RADIUS + 1.0, COLOR_BG)

	var start_angle := -PI / 2.0
	var end_angle := start_angle + fraction * TAU
	draw_arc(center, RING_RADIUS, start_angle, end_angle, 48, time_color, RING_THICKNESS, true)

	if fraction > 0.0:
		var tip_dir := Vector2.from_angle(end_angle)
		var tip_pos := center + tip_dir * RING_RADIUS
		draw_circle(tip_pos, GLOW_RADIUS, time_color.lightened(0.3))

	var label := _phase_label(fraction)
	var font := ThemeDB.fallback_font
	if font == null:
		return
	var font_size := 11
	var text_size := font.get_string_size(label, HORIZONTAL_ALIGNMENT_CENTER, -1, font_size)
	var text_x := (SIZE_DIAL - text_size.x) / 2.0
	var text_y := SIZE_DIAL - text_size.y + 4.0
	draw_string(font, Vector2(text_x, text_y), label, HORIZONTAL_ALIGNMENT_LEFT, -1, font_size, Color.WHITE)


func _cycle_fraction() -> float:
	if day_night_cycle == null:
		return 0.0
	var elapsed: float = day_night_cycle.get("elapsed") if "elapsed" in day_night_cycle else 0.0
	var duration: float = (
		day_night_cycle.get("cycle_duration_seconds")
		if "cycle_duration_seconds" in day_night_cycle
		else 240.0
	)
	if duration <= 0.0:
		return 0.0
	return fmod(elapsed / duration, 1.0)


func _time_color(fraction: float) -> Color:
	if fraction < 0.15:
		return COLOR_NIGHT
	if fraction < 0.3:
		return COLOR_NIGHT.lerp(COLOR_DAWN, smoothstep(0.15, 0.3, fraction))
	if fraction < 0.7:
		return COLOR_DAY
	if fraction < 0.85:
		return COLOR_DAY.lerp(COLOR_DUSK, smoothstep(0.7, 0.85, fraction))
	return COLOR_DUSK.lerp(COLOR_NIGHT, smoothstep(0.85, 1.0, fraction))


func _phase_label(fraction: float) -> String:
	if fraction < 0.1:
		return "Night"
	if fraction < 0.2:
		return "Dawn"
	if fraction < 0.65:
		return "Day"
	if fraction < 0.8:
		return "Dusk"
	return "Night"
