class_name MovingPlatform extends AutoPathFollow

@export var body: AnimatableBody3D
@export var area: Area3D

@onready var _area_bodies: Array[Character] = []

func _ready() -> void:
	if area:
		area.body_entered.connect(_on_area_body_entered)
		area.body_exited.connect(_on_area_body_exited)

func _physics_process(delta: float) -> void:
	super(delta)
	if body:
		body.global_position = global_position
		body.constant_linear_velocity = velocity
	for ch in _area_bodies:
		if ch.impetus.is_zero_approx() && ch.is_grounded():
			ch.state = &'idle'
			var veldiff := velocity - ch.linear_velocity
			veldiff -= veldiff.project(global_basis.y)
			ch.apply_central_impulse(ch.mass*veldiff)

func _on_area_body_entered(pbody: Node3D) -> void:
	var ch := pbody as Character
	if ch && _area_bodies.count(ch) <= 0:
		_area_bodies.push_back(ch)

func _on_area_body_exited(pbody: Node3D) -> void:
	var ch := pbody as Character
	if ch:
		while _area_bodies.count(ch) > 0:
			_area_bodies.erase(ch)