EXCELIA_DBARR/custom/booking/reservation_area.php

<?php
require_once 'reservation.class.php';
$reservation = new Reservation();
$facilitie = $_POST['facilitie'];
$areas = [
    "1" => ["1" => "Medence_1", "2" => "Medence_2", "3" => "Focipálya"],
    "2" => ["1" => "Medence_1", "2" => "Medence_2"],
    "3" => ["1" => "Medence_1", "2" => "Focipálya"]
];
print $reservation->generateSelectorInput('area', $areas[$facilitie], $area);