<?php

/*
 * FusionPBX
 * Version: MPL 1.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is FusionPBX
 *
 * The Initial Developer of the Original Code is
 * Mark J Crane <markjcrane@fusionpbx.com>
 * Portions created by the Initial Developer are Copyright (C) 2008-2025
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 * Mark J Crane <markjcrane@fusionpbx.com>
 * Tim Fry <tim@fusionpbx.com>
 */

/**
 *
 * @author Tim Fry <tim@fusionpbx.com>
 */
interface filter {
	/**
	 * Uses the __invoke magic method to create a filter
	 * There are three possible return values for a filter:
	 *   1. True - Passed
	 *   2. False - Failed
	 *   3. null - Invalid
	 * @param string $key
	 * @param mixed $value
	 * @return bool|null
	 */
	public function __invoke(string $key, $value): ?bool;
}