class_name ChairInteraction
extends Area3D
## Sit-down interaction for the treatment chair.
## Shows a prompt when the player is in range, sits them on `interact`,
## smoothly lerps the camera to a seated pose, locks movement, and emits
## `player_seated`. Standing again unlocks movement and emits `player_stood`.

signal player_seated
signal player_stood

@export var seat_transform_path: NodePath
@export var lerp_duration: float = 0.6

@onready var prompt_label: Label = $PromptLayer/PromptLabel
@onready var seat_marker: Node3D = get_node_or_null(seat_transform_path)

var _player: PlayerController = null
var _player_in_range: bool = false
var _is_seated: bool = false
var _stand_transform: Transform3D
var _tween: Tween = null


func _ready() -> void:
	if prompt_label:
		prompt_label.visible = false
	body_entered.connect(_on_body_entered)
	body_exited.connect(_on_body_exited)


func _on_body_entered(body: Node3D) -> void:
	if body is PlayerController:
		_player = body
		_player_in_range = true
		_update_prompt()


func _on_body_exited(body: Node3D) -> void:
	if body == _player and not _is_seated:
		_player_in_range = false
		_player = null
		_update_prompt()


func _unhandled_input(event: InputEvent) -> void:
	if not event.is_action_pressed("interact"):
		return
	if _is_seated:
		_stand_up()
	elif _player_in_range and _player != null:
		_sit_down()


func _update_prompt() -> void:
	if not prompt_label:
		return
	if _is_seated:
		prompt_label.text = "Press E to stand"
		prompt_label.visible = true
	elif _player_in_range:
		prompt_label.text = "Press E to sit"
		prompt_label.visible = true
	else:
		prompt_label.visible = false


func _sit_down() -> void:
	if seat_marker == null:
		push_warning("ChairInteraction: no seat marker assigned; cannot sit.")
		return
	_is_seated = true
	_stand_transform = _player.global_transform
	_player.set_movement_locked(true)
	_update_prompt()
	_lerp_player_to(seat_marker.global_transform, func() -> void:
		player_seated.emit()
	)


func _stand_up() -> void:
	_is_seated = false
	_update_prompt()
	_lerp_player_to(_stand_transform, func() -> void:
		if _player:
			_player.set_movement_locked(false)
		player_stood.emit()
		# Refresh range state after standing.
		_player_in_range = overlaps_body(_player) if _player else false
		_update_prompt()
	)


func _lerp_player_to(target: Transform3D, on_done: Callable) -> void:
	if _tween and _tween.is_running():
		_tween.kill()
	_tween = create_tween()
	_tween.set_trans(Tween.TRANS_SINE).set_ease(Tween.EASE_IN_OUT)
	_tween.tween_method(_apply_player_transform.bind(_player.global_transform, target),
		0.0, 1.0, lerp_duration)
	_tween.tween_callback(on_done)


func _apply_player_transform(t: float, from_xform: Transform3D, to_xform: Transform3D) -> void:
	if _player:
		_player.global_transform = from_xform.interpolate_with(to_xform, t)