class_name CockpitAlertBox
extends Node3D

## Drives the three lamps of the imported alert box model. Exactly one lamp is
## lit for the alert level carried by the dive snapshot; the lamps are also
## distinguished by position and by their engraved ALERTE / ATTENTION / DANGER
## plates, so the reading does not depend on colour alone.

const DiveAlertLevel = preload("res://game/domain/dive/dive_alert_level.gd")
const CockpitMeshFactory = preload("res://game/presentation/cockpit/cockpit_mesh_factory.gd")

const LAMP_NAMES: Array[String] = ["Lamp_Alerte", "Lamp_Attention", "Lamp_Danger"]
const LIT_ENERGY := 4.0
const UNLIT_ENERGY := 0.0

var _lamp_materials: Array[BaseMaterial3D] = []


func _ready() -> void:
	for lamp_name: String in LAMP_NAMES:
		var lamp := find_child(lamp_name, true, false) as MeshInstance3D
		var material := CockpitMeshFactory.own_surface_material(lamp)
		if material == null:
			push_error("Alert box model has no usable %s lamp" % lamp_name)
			continue
		material.emission_energy_multiplier = UNLIT_ENERGY
		_lamp_materials.append(material)


func present(alert_level: DiveAlertLevel.Value) -> void:
	var active_index := _lamp_index_for(alert_level)
	for lamp_index in _lamp_materials.size():
		_lamp_materials[lamp_index].emission_energy_multiplier = (
			LIT_ENERGY if lamp_index == active_index else UNLIT_ENERGY
		)


func indicator_count() -> int:
	return _lamp_materials.size()


func active_indicator_count() -> int:
	var count := 0
	for material: BaseMaterial3D in _lamp_materials:
		if material.emission_energy_multiplier > UNLIT_ENERGY:
			count += 1
	return count


func active_indicator_name() -> String:
	for lamp_index in _lamp_materials.size():
		if _lamp_materials[lamp_index].emission_energy_multiplier > UNLIT_ENERGY:
			return LAMP_NAMES[lamp_index]
	return ""


func _lamp_index_for(alert_level: DiveAlertLevel.Value) -> int:
	if alert_level >= DiveAlertLevel.Value.CRITICAL:
		return 2
	if alert_level >= DiveAlertLevel.Value.ATTENTION:
		return 1
	return 0