1<?php 2 3/** 4 * webtrees: online genealogy 5 * Copyright (C) 2021 webtrees development team 6 * This program is free software: you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation, either version 3 of the License, or 9 * (at your option) any later version. 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * You should have received a copy of the GNU General Public License 15 * along with this program. If not, see <https://www.gnu.org/licenses/>. 16 */ 17 18declare(strict_types=1); 19 20namespace Fisharebest\Webtrees\Elements; 21 22use function mb_strlen; 23use function mb_strtolower; 24use function mb_strtoupper; 25use function mb_substr; 26 27/** 28 * @see https://en.wikipedia.org/wiki/Maidenhead_Locator_System 29 */ 30class MaidenheadLocator extends AbstractElement 31{ 32 protected const MAXIMUM_LENGTH = 8; 33 protected const PATTERN = '[A-Ra-r][A-Ra-r]([0-9][0-9]([A-Xa-x][A-Xa-x]([0-9][0-9])?)?)?'; 34 35 /** 36 * Convert a value to a canonical form. 37 * 38 * @param string $value 39 * 40 * @return string 41 */ 42 public function canonical(string $value): string 43 { 44 $value = parent::canonical($value); 45 46 // Characters 1 and 2 are upper case 47 if (mb_strlen($value) >= 2) { 48 $value = mb_strtoupper(mb_substr($value, 0, 2)) . mb_substr($value, 2); 49 } 50 51 // Characters 5 and 6 are lower case 52 if (mb_strlen($value) >= 6) { 53 $value = mb_substr($value, 0, 4) . mb_strtolower(mb_substr($value, 4, 2)) . mb_substr($value, 6); 54 } 55 56 return $value; 57 } 58} 59