class_name VolumeSlider
extends HSlider
## A slider that sets the volume of an audio bus.

## The audio bus whose volume the slider sets.

@export var audio_bus_name: String = "music"

var _bus: int


func _ready() -> void:
	_bus = AudioServer.get_bus_index(audio_bus_name)
	value_changed.connect(_on_value_changed)
	value = db_to_linear(AudioServer.get_bus_volume_db(_bus))


## Sets the bus volume to [param changed_value], from 0 (silent) to 1 (full).
func change_volume(changed_value: float) -> void:
	AudioServer.set_bus_volume_db(_bus, linear_to_db(changed_value))


func _on_value_changed(changed_value: float) -> void:
	AudioServer.set_bus_volume_db(_bus, linear_to_db(changed_value))