@tool
extends PanelContainer

enum Connection { CONNECTED, DEGRADED, DISCONNECTED }

@export var downlink_capacity_gbps := 10.0
@export var uplink_capacity_gbps := 10.0
@export_range(0, 1) var warning_fraction := 0.8
@export_range(0, 1) var fault_fraction := 0.95
@export var loss_window_seconds := 10.0
@export var stale_after_seconds := 2.0
@export var link_icon: Texture2D:
	set(value):
		link_icon = value
		if is_node_ready():
			%LinkIcon.texture = value

var _received_ms := -1
var _state := Connection.CONNECTED
var _down := 0.0
var _up := 0.0
var _loss := 0.0
var _stale := false

func _ready() -> void:
	%LinkIcon.texture = link_icon
	theme_changed.connect(_update_icon)
	_update_icon()
	_refresh()

## Rates in Gbps; loss in percent over loss_window_seconds.
func set_telemetry(down: float, up: float, loss_percent: float, state: int = Connection.CONNECTED) -> bool:
	if not is_finite(down) or not is_finite(up) or not is_finite(loss_percent) or down < 0 or up < 0 or loss_percent < 0 or loss_percent > 100 or state < 0 or state > 2:
		return false
	_down = down
	_up = up
	_loss = loss_percent
	_state = state
	_received_ms = Time.get_ticks_msec()
	_refresh()
	return true

func clear_telemetry() -> void:
	_received_ms = -1
	_refresh()

func _process(_delta: float) -> void:
	var stale := _received_ms >= 0 and Time.get_ticks_msec() - _received_ms > stale_after_seconds * 1000
	if stale != _stale:
		_refresh()

func _refresh() -> void:
	if not is_node_ready():
		return
	var missing := _received_ms < 0
	_stale = not missing and Time.get_ticks_msec() - _received_ms > stale_after_seconds * 1000
	var measured := not missing and _state != Connection.DISCONNECTED
	%State.text = "NO TELEMETRY" if missing else ("STALE" if _stale else ["CONNECTED", "DEGRADED", "DISCONNECTED"][_state])
	%State.theme_type_variation = "LinkMuted" if missing else ("LinkRateWarning" if _stale or _state == Connection.DEGRADED else ("LinkRateFault" if _state == Connection.DISCONNECTED else "Label"))
	var gauges := [%Downlink, %Uplink]
	for index in range(2):
		gauges[index].capacity_gbps = maxf([downlink_capacity_gbps, uplink_capacity_gbps][index], 0.001)
		gauges[index].warning_fraction = warning_fraction
		gauges[index].fault_fraction = maxf(warning_fraction, fault_fraction)
		gauges[index].rate_gbps = [_down, _up][index]
		gauges[index].available = measured
		gauges[index].refresh()
	%LossValue.text = "%.2f%%" % _loss if measured else "—"
	%LossWindow.text = "%.0f s window" % loss_window_seconds + (" · held" if _stale else "")

func _update_icon() -> void:
	var tint := get_theme_color("status_icon", "SurfaceSide")
	tint.a = 0.06
	%LinkIcon.self_modulate = tint