Pronounce HEX value

hexadecimal.php

<?php

class HexTools
{
    private static $verbalMap = [
        '00' => 'zero',
        '-0' => '',
        '0-' => '',
        '-1' => 'one',
        '1-' => 'teen',
        '11' => 'eleven',
        '12' => 'twelve',
        '13' => 'thirteen',
        '15' => 'fifteen',
        '-2' => 'two',
        '2-' => 'twenty',
        '-3' => 'three',
        '3-' => 'thirty',
        '-4' => 'four',
        '4-' => 'fourty',
        '-5' => 'five',
        '5-' => 'fifty',
        '-6' => 'six',
        '6-' => 'sixty',
        '-7' => 'seven',
        '7-' => 'seventy',
        '-8' => 'eight',
        '8-' => 'eighty',
        '-9' => 'nine',
        '9-' => 'ninety',
        '-A' => 'ann',
        'A-' => 'annty',
        '-B' => 'bet',
        'B-' => 'betty',
        '-C' => 'chris',
        'C-' => 'christy',
        '-D' => 'dot',
        'D-' => 'dotty',
        '-E' => 'ernest',
        'E-' => 'ernestty',
        '-F' => 'frost',
        'F-' => 'frostty',
    ];

    public static function hex2verbal($hex)
    {
        $verbal = '';
        $hex = strtoupper($hex);
        $hex = preg_replace('([^0-9A-F])', '', $hex);
        $hexLen = strlen($hex);
        if ($hexLen % 2 === 1) {
            $hex = str_pad($hex, $hexLen + 1, '0', STR_PAD_LEFT);
        }
        $parts = str_split($hex, 2);
        foreach ($parts as $part) {
            $part = sprintf('%02s', $part);
            $word = self::$verbalMap[$part];
            if (!empty($word)) {
                $verbal .= $word;
            } else {
                $part1 = (string)$part[0] . '-';
                $part2 = (string)'-' . $part[1];
                if ($part1 === '1-') {
                    $word1 = self::$verbalMap[$part2];
                    $word2 = self::$verbalMap[$part1];
                    $divider = '';
                } else {
                    $word1 = self::$verbalMap[$part1];
                    $word2 = self::$verbalMap[$part2];
                    $divider = '-';
                }
                $verbal .= $word1;
                if (!empty($word1) && !empty($word2)) {
                    $verbal .= $divider;
                }
                $verbal .= $word2;
            }
            $verbal .= ' ';
        }
        return trim($verbal);
    }
}

$hex = empty($argv[1]) ? '0' : $argv[1];
echo $hex .' = ' .HexTools::hex2verbal($hex) . PHP_EOL;