extends Camera3D
## Nausea screen-tilt effect.
##
## Rolls the camera slightly on its local Z axis, oscillating over time, with
## amplitude proportional to nausea intensity. Attach to the player `Camera3D`.
## The first-person controller only writes camera rotation.x (pitch), so writing
## rotation.z here does not conflict.

## Maximum tilt in degrees at full nausea (100).
@export var max_tilt_deg: float = 5.0
## Oscillation frequency in Hz.
@export var frequency_hz: float = 0.3
## How fast the effective intensity follows the target, in intensity units/sec.
## At 200, a full 0->100 change resolves in ~0.5s.
@export var intensity_follow_speed: float = 200.0

var _target_intensity: float = 0.0
var _current_intensity: float = 0.0
var _time: float = 0.0


func _ready() -> void:
	# Resolve the SymptomManager autoload via the scene tree root when possible,
	# falling back to the global autoload identifier.
	var sm: Node = null
	if is_inside_tree():
		sm = get_tree().root.get_node_or_null("SymptomManager")
	if sm == null:
		sm = SymptomManager
	if sm:
		sm.nausea_intensity_changed.connect(_on_nausea_changed)
		_target_intensity = sm.get_intensity(sm.NAUSEA)
		_current_intensity = _target_intensity


func _on_nausea_changed(value: float) -> void:
	_target_intensity = value


func _process(delta: float) -> void:
	_time += delta
	_current_intensity = move_toward(
		_current_intensity, _target_intensity, intensity_follow_speed * delta
	)

	var amplitude := deg_to_rad(max_tilt_deg) * (_current_intensity / 100.0)
	var roll := sin(_time * TAU * frequency_hz) * amplitude
	rotation.z = roll