xref: /webtrees/app/Soundex.php (revision dd71ff6b9f8508a26dabb8d3203ec5b96f870208)

<?php

/**
 * webtrees: online genealogy
 * Copyright (C) 2021 webtrees development team
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <https://www.gnu.org/licenses/>.
 */

declare(strict_types=1);

namespace Fisharebest\Webtrees;

/**
 * Phonetic matching of strings.
 */
class Soundex
{
    // Determine the Daitch–Mokotoff Soundex code for a word
    // Original implementation by Gerry Kroll, and analysis by Meliza Amity

    // Max. table key length (in ASCII bytes -- NOT in UTF-8 characters!)
    private const MAXCHAR = 7;

    /**
     * Name transformation arrays.
     * Used to transform the Name string to simplify the "sounds like" table.
     * This is especially useful in Hebrew.
     *
     * Each array entry defines the "from" and "to" arguments of an preg($from, $to, $text)
     * function call to achieve the desired transformations.
     *
     * Note about the use of "\x01":
     * This code, which can’t legitimately occur in the kind of text we're dealing with,
     * is used as a place-holder so that conditional string replacements can be done.
     */
    private const TRANSFORM_NAMES = [
        // Force Yiddish ligatures to be treated as separate letters
        [
            'װ',
            'וו',
        ],
        [
            'ײ',
            'יי',
        ],
        [
            'ױ',
            'וי',
        ],
        [
            'בו',
            'בע',
        ],
        [
            'פו',
            'פע',
        ],
        [
            'ומ',
            'עמ',
        ],
        [
            'ום',
            'עם',
        ],
        [
            'ונ',
            'ענ',
        ],
        [
            'ון',
            'ען',
        ],
        [
            'וו',
            'ב',
        ],
        [
            "\x01",
            '',
        ],
        [
            'ייה$',
            "\x01ה",
        ],
        [
            'ייע$',
            "\x01ע",
        ],
        [
            'יי',
            'ע',
        ],
        [
            "\x01",
            'יי',
        ],
    ];

    /**
     * The DM sound coding table is organized this way:
     * key: a variable-length string that corresponds to the UTF-8 character sequence
     * represented by the table entry. Currently, that string can be up to 7
     * bytes long. This maximum length is defined by the value of global variable
     * $maxchar.
     *
     * value: an array as follows:
     * [0]:  zero if not a vowel
     * [1]:  sound value when this string is at the beginning of the word
     * [2]:  sound value when this string is followed by a vowel
     * [3]:  sound value for other cases
     * [1],[2],[3] can be repeated several times to create branches in the code
     * an empty sound value means "ignore in this state"
     */
    private const DM_SOUNDS = [
        'A'       => [
            '1',
            '0',
            '',
            '',
        ],
        'À'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Á'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Â'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ã'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ä'       => [
            '1',
            '0',
            '1',
            '',
            '0',
            '',
            '',
        ],
        'Å'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ă'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ą'       => [
            '1',
            '',
            '',
            '',
            '',
            '',
            '6',
        ],
        'Ạ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ả'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ấ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ầ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ẩ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ẫ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ậ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ắ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ằ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ẳ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ẵ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ặ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'AE'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'Æ'       => [
            '1',
            '0',
            '1',
            '',
        ],
        'AI'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'AJ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'AU'      => [
            '1',
            '0',
            '7',
            '',
        ],
        'AV'      => [
            '1',
            '0',
            '7',
            '',
            '7',
            '7',
            '7',
        ],
        'ÄU'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'AY'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'B'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'C'       => [
            '0',
            '5',
            '5',
            '5',
            '34',
            '4',
            '4',
        ],
        'Ć'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Č'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Ç'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'CH'      => [
            '0',
            '5',
            '5',
            '5',
            '34',
            '4',
            '4',
        ],
        'CHS'     => [
            '0',
            '5',
            '54',
            '54',
        ],
        'CK'      => [
            '0',
            '5',
            '5',
            '5',
            '45',
            '45',
            '45',
        ],
        'CCS'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'CS'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'CSZ'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'CZ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'CZS'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'D'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'Ď'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'Đ'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'DRS'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DRZ'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DS'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DSH'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DSZ'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DT'      => [
            '0',
            '3',
            '3',
            '3',
        ],
        'DDZ'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DDZS'    => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DZ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DŹ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DŻ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DZH'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'DZS'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'E'       => [
            '1',
            '0',
            '',
            '',
        ],
        'È'       => [
            '1',
            '0',
            '',
            '',
        ],
        'É'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ê'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ë'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ĕ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ė'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ę'       => [
            '1',
            '',
            '',
            '6',
            '',
            '',
            '',
        ],
        'Ẹ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ẻ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ẽ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ế'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ề'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ể'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ễ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ệ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'EAU'     => [
            '1',
            '0',
            '',
            '',
        ],
        'EI'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'EJ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'EU'      => [
            '1',
            '1',
            '1',
            '',
        ],
        'EY'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'F'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'FB'      => [
            '0',
            '7',
            '7',
            '7',
        ],
        'G'       => [
            '0',
            '5',
            '5',
            '5',
            '34',
            '4',
            '4',
        ],
        'Ğ'       => [
            '0',
            '',
            '',
            '',
        ],
        'GGY'     => [
            '0',
            '5',
            '5',
            '5',
        ],
        'GY'      => [
            '0',
            '5',
            '5',
            '5',
        ],
        'H'       => [
            '0',
            '5',
            '5',
            '',
            '5',
            '5',
            '5',
        ],
        'I'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ì'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Í'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Î'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ï'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ĩ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Į'       => [
            '1',
            '0',
            '',
            '',
        ],
        'İ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ỉ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ị'       => [
            '1',
            '0',
            '',
            '',
        ],
        'IA'      => [
            '1',
            '1',
            '',
            '',
        ],
        'IE'      => [
            '1',
            '1',
            '',
            '',
        ],
        'IO'      => [
            '1',
            '1',
            '',
            '',
        ],
        'IU'      => [
            '1',
            '1',
            '',
            '',
        ],
        'J'       => [
            '0',
            '1',
            '',
            '',
            '4',
            '4',
            '4',
            '5',
            '5',
            '',
        ],
        'K'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'KH'      => [
            '0',
            '5',
            '5',
            '5',
        ],
        'KS'      => [
            '0',
            '5',
            '54',
            '54',
        ],
        'L'       => [
            '0',
            '8',
            '8',
            '8',
        ],
        'Ľ'       => [
            '0',
            '8',
            '8',
            '8',
        ],
        'Ĺ'       => [
            '0',
            '8',
            '8',
            '8',
        ],
        'Ł'       => [
            '0',
            '7',
            '7',
            '7',
            '8',
            '8',
            '8',
        ],
        'LL'      => [
            '0',
            '8',
            '8',
            '8',
            '58',
            '8',
            '8',
            '1',
            '8',
            '8',
        ],
        'LLY'     => [
            '0',
            '8',
            '8',
            '8',
            '1',
            '8',
            '8',
        ],
        'LY'      => [
            '0',
            '8',
            '8',
            '8',
            '1',
            '8',
            '8',
        ],
        'M'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'MĔ'      => [
            '0',
            '66',
            '66',
            '66',
        ],
        'MN'      => [
            '0',
            '66',
            '66',
            '66',
        ],
        'N'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'Ń'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'Ň'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'Ñ'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'NM'      => [
            '0',
            '66',
            '66',
            '66',
        ],
        'O'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ò'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ó'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ô'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Õ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ö'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ø'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ő'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Œ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ơ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ọ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ỏ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ố'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ồ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ổ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ỗ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ộ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ớ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ờ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ở'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ỡ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ợ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'OE'      => [
            '1',
            '0',
            '',
            '',
        ],
        'OI'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'OJ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'OU'      => [
            '1',
            '0',
            '',
            '',
        ],
        'OY'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'P'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'PF'      => [
            '0',
            '7',
            '7',
            '7',
        ],
        'PH'      => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Q'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'R'       => [
            '0',
            '9',
            '9',
            '9',
        ],
        'Ř'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'RS'      => [
            '0',
            '4',
            '4',
            '4',
            '94',
            '94',
            '94',
        ],
        'RZ'      => [
            '0',
            '4',
            '4',
            '4',
            '94',
            '94',
            '94',
        ],
        'S'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Ś'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Š'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Ş'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'SC'      => [
            '0',
            '2',
            '4',
            '4',
        ],
        'ŠČ'      => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SCH'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'SCHD'    => [
            '0',
            '2',
            '43',
            '43',
        ],
        'SCHT'    => [
            '0',
            '2',
            '43',
            '43',
        ],
        'SCHTCH'  => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SCHTSCH' => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SCHTSH'  => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SD'      => [
            '0',
            '2',
            '43',
            '43',
        ],
        'SH'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'SHCH'    => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SHD'     => [
            '0',
            '2',
            '43',
            '43',
        ],
        'SHT'     => [
            '0',
            '2',
            '43',
            '43',
        ],
        'SHTCH'   => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SHTSH'   => [
            '0',
            '2',
            '4',
            '4',
        ],
        'ß'       => [
            '0',
            '',
            '4',
            '4',
        ],
        'ST'      => [
            '0',
            '2',
            '43',
            '43',
        ],
        'STCH'    => [
            '0',
            '2',
            '4',
            '4',
        ],
        'STRS'    => [
            '0',
            '2',
            '4',
            '4',
        ],
        'STRZ'    => [
            '0',
            '2',
            '4',
            '4',
        ],
        'STSCH'   => [
            '0',
            '2',
            '4',
            '4',
        ],
        'STSH'    => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SSZ'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'SZ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'SZCS'    => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SZCZ'    => [
            '0',
            '2',
            '4',
            '4',
        ],
        'SZD'     => [
            '0',
            '2',
            '43',
            '43',
        ],
        'SZT'     => [
            '0',
            '2',
            '43',
            '43',
        ],
        'T'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'Ť'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'Ţ'       => [
            '0',
            '3',
            '3',
            '3',
            '4',
            '4',
            '4',
        ],
        'TC'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TCH'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TH'      => [
            '0',
            '3',
            '3',
            '3',
        ],
        'TRS'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TRZ'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TS'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TSCH'    => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TSH'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TSZ'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TTCH'    => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TTS'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TTSCH'   => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TTSZ'    => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TTZ'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TZ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'TZS'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'U'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ù'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ú'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Û'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ü'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ũ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ū'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ů'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ű'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ų'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ư'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ụ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ủ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ứ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ừ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ử'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ữ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ự'       => [
            '1',
            '0',
            '',
            '',
        ],
        'UE'      => [
            '1',
            '0',
            '',
            '',
        ],
        'UI'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'UJ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'UY'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'UW'      => [
            '1',
            '0',
            '1',
            '',
            '0',
            '7',
            '7',
        ],
        'V'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'W'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'X'       => [
            '0',
            '5',
            '54',
            '54',
        ],
        'Y'       => [
            '1',
            '1',
            '',
            '',
        ],
        'Ý'       => [
            '1',
            '1',
            '',
            '',
        ],
        'Ỳ'       => [
            '1',
            '1',
            '',
            '',
        ],
        'Ỵ'       => [
            '1',
            '1',
            '',
            '',
        ],
        'Ỷ'       => [
            '1',
            '1',
            '',
            '',
        ],
        'Ỹ'       => [
            '1',
            '1',
            '',
            '',
        ],
        'Z'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Ź'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Ż'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Ž'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ZD'      => [
            '0',
            '2',
            '43',
            '43',
        ],
        'ZDZ'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'ZDZH'    => [
            '0',
            '2',
            '4',
            '4',
        ],
        'ZH'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ZHD'     => [
            '0',
            '2',
            '43',
            '43',
        ],
        'ZHDZH'   => [
            '0',
            '2',
            '4',
            '4',
        ],
        'ZS'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ZSCH'    => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ZSH'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ZZS'     => [
            '0',
            '4',
            '4',
            '4',
        ],
        // Cyrillic alphabet
        'А'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Б'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'В'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Г'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'Д'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'ДЗ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Е'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ё'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ж'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'З'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'И'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Й'       => [
            '1',
            '1',
            '',
            '',
            '4',
            '4',
            '4',
        ],
        'К'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'Л'       => [
            '0',
            '8',
            '8',
            '8',
        ],
        'М'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'Н'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'О'       => [
            '1',
            '0',
            '',
            '',
        ],
        'П'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Р'       => [
            '0',
            '9',
            '9',
            '9',
        ],
        'РЖ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'С'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Т'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'У'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ф'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Х'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'Ц'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Ч'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Ш'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Щ'       => [
            '0',
            '2',
            '4',
            '4',
        ],
        'Ъ'       => [
            '0',
            '',
            '',
            '',
        ],
        'Ы'       => [
            '0',
            '1',
            '',
            '',
        ],
        'Ь'       => [
            '0',
            '',
            '',
            '',
        ],
        'Э'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ю'       => [
            '0',
            '1',
            '',
            '',
        ],
        'Я'       => [
            '0',
            '1',
            '',
            '',
        ],
        // Greek alphabet
        'Α'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ά'       => [
            '1',
            '0',
            '',
            '',
        ],
        'ΑΙ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'ΑΥ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'Β'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Γ'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'Δ'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'Ε'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Έ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'ΕΙ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'ΕΥ'      => [
            '1',
            '1',
            '1',
            '',
        ],
        'Ζ'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Η'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ή'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Θ'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'Ι'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ί'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ϊ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'ΐ'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Κ'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'Λ'       => [
            '0',
            '8',
            '8',
            '8',
        ],
        'Μ'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'ΜΠ'      => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Ν'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'ΝΤ'      => [
            '0',
            '3',
            '3',
            '3',
        ],
        'Ξ'       => [
            '0',
            '5',
            '54',
            '54',
        ],
        'Ο'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ό'       => [
            '1',
            '0',
            '',
            '',
        ],
        'ΟΙ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'ΟΥ'      => [
            '1',
            '0',
            '1',
            '',
        ],
        'Π'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Ρ'       => [
            '0',
            '9',
            '9',
            '9',
        ],
        'Σ'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ς'       => [
            '0',
            '',
            '',
            '4',
        ],
        'Τ'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'ΤΖ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ΤΣ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'Υ'       => [
            '1',
            '1',
            '',
            '',
        ],
        'Ύ'       => [
            '1',
            '1',
            '',
            '',
        ],
        'Ϋ'       => [
            '1',
            '1',
            '',
            '',
        ],
        'ΰ'       => [
            '1',
            '1',
            '',
            '',
        ],
        'ΥΚ'      => [
            '1',
            '5',
            '5',
            '5',
        ],
        'ΥΥ'      => [
            '1',
            '65',
            '65',
            '65',
        ],
        'Φ'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Χ'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'Ψ'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'Ω'       => [
            '1',
            '0',
            '',
            '',
        ],
        'Ώ'       => [
            '1',
            '0',
            '',
            '',
        ],
        // Hebrew alphabet
        'א'       => [
            '1',
            '0',
            '',
            '',
        ],
        'או'      => [
            '1',
            '0',
            '7',
            '',
        ],
        'אג'      => [
            '1',
            '4',
            '4',
            '4',
            '5',
            '5',
            '5',
            '34',
            '34',
            '34',
        ],
        'בב'      => [
            '0',
            '7',
            '7',
            '7',
            '77',
            '77',
            '77',
        ],
        'ב'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'גג'      => [
            '0',
            '4',
            '4',
            '4',
            '5',
            '5',
            '5',
            '45',
            '45',
            '45',
            '55',
            '55',
            '55',
            '54',
            '54',
            '54',
        ],
        'גד'      => [
            '0',
            '43',
            '43',
            '43',
            '53',
            '53',
            '53',
        ],
        'גה'      => [
            '0',
            '45',
            '45',
            '45',
            '55',
            '55',
            '55',
        ],
        'גז'      => [
            '0',
            '44',
            '44',
            '44',
            '45',
            '45',
            '45',
        ],
        'גח'      => [
            '0',
            '45',
            '45',
            '45',
            '55',
            '55',
            '55',
        ],
        'גכ'      => [
            '0',
            '45',
            '45',
            '45',
            '55',
            '55',
            '55',
        ],
        'גך'      => [
            '0',
            '45',
            '45',
            '45',
            '55',
            '55',
            '55',
        ],
        'גצ'      => [
            '0',
            '44',
            '44',
            '44',
            '45',
            '45',
            '45',
        ],
        'גץ'      => [
            '0',
            '44',
            '44',
            '44',
            '45',
            '45',
            '45',
        ],
        'גק'      => [
            '0',
            '45',
            '45',
            '45',
            '54',
            '54',
            '54',
        ],
        'גש'      => [
            '0',
            '44',
            '44',
            '44',
            '54',
            '54',
            '54',
        ],
        'גת'      => [
            '0',
            '43',
            '43',
            '43',
            '53',
            '53',
            '53',
        ],
        'ג'       => [
            '0',
            '4',
            '4',
            '4',
            '5',
            '5',
            '5',
        ],
        'דז'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'דד'      => [
            '0',
            '3',
            '3',
            '3',
            '33',
            '33',
            '33',
        ],
        'דט'      => [
            '0',
            '33',
            '33',
            '33',
        ],
        'דש'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'דצ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'דץ'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ד'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'הג'      => [
            '0',
            '54',
            '54',
            '54',
            '55',
            '55',
            '55',
        ],
        'הכ'      => [
            '0',
            '55',
            '55',
            '55',
        ],
        'הח'      => [
            '0',
            '55',
            '55',
            '55',
        ],
        'הק'      => [
            '0',
            '55',
            '55',
            '55',
            '5',
            '5',
            '5',
        ],
        'הה'      => [
            '0',
            '5',
            '5',
            '',
            '55',
            '55',
            '',
        ],
        'ה'       => [
            '0',
            '5',
            '5',
            '',
        ],
        'וי'      => [
            '1',
            '',
            '',
            '',
            '7',
            '7',
            '7',
        ],
        'ו'       => [
            '1',
            '7',
            '7',
            '7',
            '7',
            '',
            '',
        ],
        'וו'      => [
            '1',
            '7',
            '7',
            '7',
            '7',
            '',
            '',
        ],
        'וופ'     => [
            '1',
            '7',
            '7',
            '7',
            '77',
            '77',
            '77',
        ],
        'זש'      => [
            '0',
            '4',
            '4',
            '4',
            '44',
            '44',
            '44',
        ],
        'זדז'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'ז'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'זג'      => [
            '0',
            '44',
            '44',
            '44',
            '45',
            '45',
            '45',
        ],
        'זז'      => [
            '0',
            '4',
            '4',
            '4',
            '44',
            '44',
            '44',
        ],
        'זס'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'זצ'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'זץ'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'חג'      => [
            '0',
            '54',
            '54',
            '54',
            '53',
            '53',
            '53',
        ],
        'חח'      => [
            '0',
            '5',
            '5',
            '5',
            '55',
            '55',
            '55',
        ],
        'חק'      => [
            '0',
            '55',
            '55',
            '55',
            '5',
            '5',
            '5',
        ],
        'חכ'      => [
            '0',
            '45',
            '45',
            '45',
            '55',
            '55',
            '55',
        ],
        'חס'      => [
            '0',
            '5',
            '54',
            '54',
        ],
        'חש'      => [
            '0',
            '5',
            '54',
            '54',
        ],
        'ח'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'טש'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'טד'      => [
            '0',
            '33',
            '33',
            '33',
        ],
        'טי'      => [
            '0',
            '3',
            '3',
            '3',
            '4',
            '4',
            '4',
            '3',
            '3',
            '34',
        ],
        'טת'      => [
            '0',
            '33',
            '33',
            '33',
        ],
        'טט'      => [
            '0',
            '3',
            '3',
            '3',
            '33',
            '33',
            '33',
        ],
        'ט'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'י'       => [
            '1',
            '1',
            '',
            '',
        ],
        'יא'      => [
            '1',
            '1',
            '',
            '',
            '1',
            '1',
            '1',
        ],
        'כג'      => [
            '0',
            '55',
            '55',
            '55',
            '54',
            '54',
            '54',
        ],
        'כש'      => [
            '0',
            '5',
            '54',
            '54',
        ],
        'כס'      => [
            '0',
            '5',
            '54',
            '54',
        ],
        'ככ'      => [
            '0',
            '5',
            '5',
            '5',
            '55',
            '55',
            '55',
        ],
        'כך'      => [
            '0',
            '5',
            '5',
            '5',
            '55',
            '55',
            '55',
        ],
        'כ'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'כח'      => [
            '0',
            '55',
            '55',
            '55',
            '5',
            '5',
            '5',
        ],
        'ך'       => [
            '0',
            '',
            '5',
            '5',
        ],
        'ל'       => [
            '0',
            '8',
            '8',
            '8',
        ],
        'לל'      => [
            '0',
            '88',
            '88',
            '88',
            '8',
            '8',
            '8',
        ],
        'מנ'      => [
            '0',
            '66',
            '66',
            '66',
        ],
        'מן'      => [
            '0',
            '66',
            '66',
            '66',
        ],
        'ממ'      => [
            '0',
            '6',
            '6',
            '6',
            '66',
            '66',
            '66',
        ],
        'מם'      => [
            '0',
            '6',
            '6',
            '6',
            '66',
            '66',
            '66',
        ],
        'מ'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'ם'       => [
            '0',
            '',
            '6',
            '6',
        ],
        'נמ'      => [
            '0',
            '66',
            '66',
            '66',
        ],
        'נם'      => [
            '0',
            '66',
            '66',
            '66',
        ],
        'ננ'      => [
            '0',
            '6',
            '6',
            '6',
            '66',
            '66',
            '66',
        ],
        'נן'      => [
            '0',
            '6',
            '6',
            '6',
            '66',
            '66',
            '66',
        ],
        'נ'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'ן'       => [
            '0',
            '',
            '6',
            '6',
        ],
        'סתש'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'סתז'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'סטז'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'סטש'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'סצד'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'סט'      => [
            '0',
            '2',
            '4',
            '4',
            '43',
            '43',
            '43',
        ],
        'סת'      => [
            '0',
            '2',
            '4',
            '4',
            '43',
            '43',
            '43',
        ],
        'סג'      => [
            '0',
            '44',
            '44',
            '44',
            '4',
            '4',
            '4',
        ],
        'סס'      => [
            '0',
            '4',
            '4',
            '4',
            '44',
            '44',
            '44',
        ],
        'סצ'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'סץ'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'סז'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'סש'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'ס'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ע'       => [
            '1',
            '0',
            '',
            '',
        ],
        'פב'      => [
            '0',
            '7',
            '7',
            '7',
            '77',
            '77',
            '77',
        ],
        'פוו'     => [
            '0',
            '7',
            '7',
            '7',
            '77',
            '77',
            '77',
        ],
        'פפ'      => [
            '0',
            '7',
            '7',
            '7',
            '77',
            '77',
            '77',
        ],
        'פף'      => [
            '0',
            '7',
            '7',
            '7',
            '77',
            '77',
            '77',
        ],
        'פ'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'ף'       => [
            '0',
            '',
            '7',
            '7',
        ],
        'צג'      => [
            '0',
            '44',
            '44',
            '44',
            '45',
            '45',
            '45',
        ],
        'צז'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'צס'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'צצ'      => [
            '0',
            '4',
            '4',
            '4',
            '5',
            '5',
            '5',
            '44',
            '44',
            '44',
            '54',
            '54',
            '54',
            '45',
            '45',
            '45',
        ],
        'צץ'      => [
            '0',
            '4',
            '4',
            '4',
            '5',
            '5',
            '5',
            '44',
            '44',
            '44',
            '54',
            '54',
            '54',
        ],
        'צש'      => [
            '0',
            '44',
            '44',
            '44',
            '4',
            '4',
            '4',
            '5',
            '5',
            '5',
        ],
        'צ'       => [
            '0',
            '4',
            '4',
            '4',
            '5',
            '5',
            '5',
        ],
        'ץ'       => [
            '0',
            '',
            '4',
            '4',
        ],
        'קה'      => [
            '0',
            '55',
            '55',
            '5',
        ],
        'קס'      => [
            '0',
            '5',
            '54',
            '54',
        ],
        'קש'      => [
            '0',
            '5',
            '54',
            '54',
        ],
        'קק'      => [
            '0',
            '5',
            '5',
            '5',
            '55',
            '55',
            '55',
        ],
        'קח'      => [
            '0',
            '55',
            '55',
            '55',
        ],
        'קכ'      => [
            '0',
            '55',
            '55',
            '55',
        ],
        'קך'      => [
            '0',
            '55',
            '55',
            '55',
        ],
        'קג'      => [
            '0',
            '55',
            '55',
            '55',
            '54',
            '54',
            '54',
        ],
        'ק'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'רר'      => [
            '0',
            '99',
            '99',
            '99',
            '9',
            '9',
            '9',
        ],
        'ר'       => [
            '0',
            '9',
            '9',
            '9',
        ],
        'שטז'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'שתש'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'שתז'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'שטש'     => [
            '0',
            '2',
            '4',
            '4',
        ],
        'שד'      => [
            '0',
            '2',
            '43',
            '43',
        ],
        'שז'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'שס'      => [
            '0',
            '44',
            '44',
            '44',
        ],
        'שת'      => [
            '0',
            '2',
            '43',
            '43',
        ],
        'שג'      => [
            '0',
            '4',
            '4',
            '4',
            '44',
            '44',
            '44',
            '4',
            '43',
            '43',
        ],
        'שט'      => [
            '0',
            '2',
            '43',
            '43',
            '44',
            '44',
            '44',
        ],
        'שצ'      => [
            '0',
            '44',
            '44',
            '44',
            '45',
            '45',
            '45',
        ],
        'שץ'      => [
            '0',
            '44',
            '',
            '44',
            '45',
            '',
            '45',
        ],
        'שש'      => [
            '0',
            '4',
            '4',
            '4',
            '44',
            '44',
            '44',
        ],
        'ש'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'תג'      => [
            '0',
            '34',
            '34',
            '34',
        ],
        'תז'      => [
            '0',
            '34',
            '34',
            '34',
        ],
        'תש'      => [
            '0',
            '4',
            '4',
            '4',
        ],
        'תת'      => [
            '0',
            '3',
            '3',
            '3',
            '4',
            '4',
            '4',
            '33',
            '33',
            '33',
            '44',
            '44',
            '44',
            '34',
            '34',
            '34',
            '43',
            '43',
            '43',
        ],
        'ת'       => [
            '0',
            '3',
            '3',
            '3',
            '4',
            '4',
            '4',
        ],
        // Arabic alphabet
        'ا'       => [
            '1',
            '0',
            '',
            '',
        ],
        'ب'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'ت'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'ث'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'ج'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ح'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'خ'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'د'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'ذ'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'ر'       => [
            '0',
            '9',
            '9',
            '9',
        ],
        'ز'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'س'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ش'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ص'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ض'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'ط'       => [
            '0',
            '3',
            '3',
            '3',
        ],
        'ظ'       => [
            '0',
            '4',
            '4',
            '4',
        ],
        'ع'       => [
            '1',
            '0',
            '',
            '',
        ],
        'غ'       => [
            '0',
            '0',
            '',
            '',
        ],
        'ف'       => [
            '0',
            '7',
            '7',
            '7',
        ],
        'ق'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'ك'       => [
            '0',
            '5',
            '5',
            '5',
        ],
        'ل'       => [
            '0',
            '8',
            '8',
            '8',
        ],
        'لا'      => [
            '0',
            '8',
            '8',
            '8',
        ],
        'م'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'ن'       => [
            '0',
            '6',
            '6',
            '6',
        ],
        'هن'      => [
            '0',
            '66',
            '66',
            '66',
        ],
        'ه'       => [
            '0',
            '5',
            '5',
            '',
        ],
        'و'       => [
            '1',
            '',
            '',
            '',
            '7',
            '',
            '',
        ],
        'ي'       => [
            '0',
            '1',
            '',
            '',
        ],
        'آ'       => [
            '0',
            '1',
            '',
            '',
        ],
        'ة'       => [
            '0',
            '',
            '',
            '3',
        ],
        'ی'       => [
            '0',
            '1',
            '',
            '',
        ],
        'ى'       => [
            '1',
            '1',
            '',
            '',
        ],
    ];

    /**
     * Which algorithms are supported.
     *
     * @return array<string>
     */
    public static function getAlgorithms(): array
    {
        return [
            /* I18N: https://en.wikipedia.org/wiki/Soundex */
            'std' => I18N::translate('Russell'),
            /* I18N: https://en.wikipedia.org/wiki/Daitch–Mokotoff_Soundex */
            'dm'  => I18N::translate('Daitch-Mokotoff'),
        ];
    }

    /**
     * Is there a match between two soundex codes?
     *
     * @param string $soundex1
     * @param string $soundex2
     *
     * @return bool
     */
    public static function compare(string $soundex1, string $soundex2): bool
    {
        if ($soundex1 !== '' && $soundex2 !== '') {
            return array_intersect(explode(':', $soundex1), explode(':', $soundex2)) !== [];
        }

        return false;
    }

    /**
     * Generate Russell soundex codes for a given text.
     *
     * @param string $text
     *
     * @return string
     */
    public static function russell(string $text): string
    {
        $words         = explode(' ', $text);
        $soundex_array = [];

        foreach ($words as $word) {
            $soundex = soundex($word);

            // Only return codes from recognisable sounds
            if ($soundex !== '0000') {
                $soundex_array[] = $soundex;
            }
        }

        // Combine words, e.g. “New York” as “Newyork”
        if (count($words) > 1) {
            $soundex_array[] = soundex(str_replace(' ', '', $text));
        }

        // A varchar(255) column can only hold 51 4-character codes (plus 50 delimiters)
        $soundex_array = array_slice(array_unique($soundex_array), 0, 51);

        return implode(':', $soundex_array);
    }

    /**
     * Generate Daitch–Mokotoff soundex codes for a given text.
     *
     * @param string $text
     *
     * @return string
     */
    public static function daitchMokotoff(string $text): string
    {
        $words         = explode(' ', $text);
        $soundex_array = [];

        foreach ($words as $word) {
            $soundex_array = array_merge($soundex_array, self::daitchMokotoffWord($word));
        }
        // Combine words, e.g. “New York” as “Newyork”
        if (count($words) > 1) {
            $soundex_array = array_merge($soundex_array, self::daitchMokotoffWord(str_replace(' ', '', $text)));
        }

        // A varchar(255) column can only hold 36 6-character codes (plus 35 delimiters)
        $soundex_array = array_slice(array_unique($soundex_array), 0, 36);

        return implode(':', $soundex_array);
    }

    /**
     * Calculate the Daitch-Mokotoff soundex for a word.
     *
     * @param string $name
     *
     * @return array<string> List of possible DM codes for the word.
     */
    private static function daitchMokotoffWord(string $name): array
    {
        // Apply special transformation rules to the input string
        $name = I18N::strtoupper($name);
        foreach (self::TRANSFORM_NAMES as $transformRule) {
            $name = str_replace($transformRule[0], $transformRule[1], $name);
        }

        // Initialize
        $name_script = I18N::textScript($name);
        $noVowels    = $name_script === 'Hebr' || $name_script === 'Arab';

        $lastPos         = strlen($name) - 1;
        $currPos         = 0;
        $state           = 1; // 1: start of input string, 2: before vowel, 3: other
        $result          = []; // accumulate complete 6-digit D-M codes here
        $partialResult   = []; // accumulate incomplete D-M codes here
        $partialResult[] = ['!']; // initialize 1st partial result  ('!' stops "duplicate sound" check)

        // Loop through the input string.
        // Stop when the string is exhausted or when no more partial results remain
        while (count($partialResult) !== 0 && $currPos <= $lastPos) {
            // Find the DM coding table entry for the chunk at the current position
            $thisEntry = substr($name, $currPos, self::MAXCHAR); // Get maximum length chunk
            while ($thisEntry !== '') {
                if (isset(self::DM_SOUNDS[$thisEntry])) {
                    break;
                }
                $thisEntry = substr($thisEntry, 0, -1); // Not in table: try a shorter chunk
            }
            if ($thisEntry === '') {
                $currPos++; // Not in table: advance pointer to next byte
                continue; // and try again
            }

            $soundTableEntry = self::DM_SOUNDS[$thisEntry];
            $workingResult   = $partialResult;
            $partialResult   = [];
            $currPos += strlen($thisEntry);

            // Not at beginning of input string
            if ($state !== 1) {
                if ($currPos <= $lastPos) {
                    // Determine whether the next chunk is a vowel
                    $nextEntry = substr($name, $currPos, self::MAXCHAR); // Get maximum length chunk
                    while ($nextEntry !== '') {
                        if (isset(self::DM_SOUNDS[$nextEntry])) {
                            break;
                        }
                        $nextEntry = substr($nextEntry, 0, -1); // Not in table: try a shorter chunk
                    }
                } else {
                    $nextEntry = '';
                }
                if ($nextEntry !== '' && self::DM_SOUNDS[$nextEntry][0] !== '0') {
                    $state = 2;
                } else {
                    // Next chunk is a vowel
                    $state = 3;
                }
            }

            while ($state < count($soundTableEntry)) {
                // empty means 'ignore this sound in this state'
                if ($soundTableEntry[$state] === '') {
                    foreach ($workingResult as $workingEntry) {
                        $tempEntry                        = $workingEntry;
                        $tempEntry[count($tempEntry) - 1] .= '!'; // Prevent false 'doubles'
                        $partialResult[]                  = $tempEntry;
                    }
                } else {
                    foreach ($workingResult as $workingEntry) {
                        if ($soundTableEntry[$state] !== $workingEntry[count($workingEntry) - 1]) {
                            // Incoming sound isn't a duplicate of the previous sound
                            $workingEntry[] = $soundTableEntry[$state];
                        } elseif ($noVowels) {
                            // Incoming sound is a duplicate of the previous sound
                            // For Hebrew and Arabic, we need to create a pair of D-M sound codes,
                            // one of the pair with only a single occurrence of the duplicate sound,
                            // the other with both occurrences
                            $workingEntry[] = $soundTableEntry[$state];
                        }

                        if (count($workingEntry) < 7) {
                            $partialResult[] = $workingEntry;
                        } else {
                            // This is the 6th code in the sequence
                            // We're looking for 7 entries because the first is '!' and doesn't count
                            $tempResult = str_replace('!', '', implode('', $workingEntry));
                            // Only return codes from recognisable sounds
                            if ($tempResult) {
                                $result[] = substr($tempResult . '000000', 0, 6);
                            }
                        }
                    }
                }
                $state += 3; // Advance to next triplet while keeping the same basic state
            }
        }

        // Zero-fill and copy all remaining partial results
        foreach ($partialResult as $workingEntry) {
            $tempResult = str_replace('!', '', implode('', $workingEntry));
            // Only return codes from recognisable sounds
            if ($tempResult) {
                $result[] = substr($tempResult . '000000', 0, 6);
            }
        }

        return $result;
    }
}