ISO-3166-1-Alpha-2 Country Code to Unicode Emoji

CountryCodeToEmoji.php

<?php
function countryCodeGetEmoji($countryCode = 'XX', $continent = 'XX'): string
{
    try {
        if (strlen($countryCode) !== 2) {
            throw new InvalidArgumentException('Invalid country code');
        }
        if ($countryCode === 'XX') {
            return mb_convert_encoding("&#x1F310;", 'UTF-8', 'HTML-ENTITIES');
        }
        if ($countryCode === 'T1') {
            return mb_convert_encoding("&#x1F310;", 'UTF-8', 'HTML-ENTITIES');
        }
        $firstLetter = dechex(ord(substr($countryCode, 0, 1)) - 0x41 + 0x1F1E6);
        $secondLetter = dechex(ord(substr($countryCode, 1, 1)) - 0x41 + 0x1F1E6);
        $flag = mb_convert_encoding("&#x$firstLetter;", 'UTF-8', 'HTML-ENTITIES') . mb_convert_encoding("&#x$secondLetter;", 'UTF-8', 'HTML-ENTITIES');
    } catch (Throwable) {
        /** @noinspection PhpDuplicateMatchArmBodyInspection */
        $flag = match ($continent) {
            'AF', 'EU' => mb_convert_encoding("&#x1F30D;", 'UTF-8', 'HTML-ENTITIES'),
            'NA', 'SA' => mb_convert_encoding("&#x1F30E;", 'UTF-8', 'HTML-ENTITIES'),
            'AS', 'OC' => mb_convert_encoding("&#x1F30F;", 'UTF-8', 'HTML-ENTITIES'),
            'AN', 'T1' => mb_convert_encoding("&#x1F310;", 'UTF-8', 'HTML-ENTITIES'),
            default => mb_convert_encoding("&#x1F310;", 'UTF-8', 'HTML-ENTITIES'),
        };
    }
    return $flag;
}