Laminas Country Code Filter

CountryCodeFilter.php

<?php

declare(strict_types=1);

namespace Api\Filter;

use Laminas\Filter\FilterInterface;
use League\ISO3166\ISO3166;
use Throwable;

/**
 * Converts country names and ISO alpha3/numeric to ISO alpha2.
 */
class CountryCodeFilter implements FilterInterface
{

    /**
     * @var string
     */
    protected $returnKey;

    /**
     * Sets filter options
     *
     * @param  string $returnKey
     */
    public function __construct($returnKey = 'alpha2')
    {
        $this->returnKey = $returnKey;
    }

    /**
     * @inheritDoc
     */
    public function filter($value)
    {
        if (null === $value) {
            return $value;
        }

        $value = (string) $value;

        $iso = new ISO3166();

        // maybe alpha2
        if (1 === preg_match('/^[a-zA-Z]{2}$/', $value)) {
            try {
                $data = $iso->alpha2($value);

                return $data[$this->returnKey];
            } catch (Throwable $e) {
            }
        }

        // maybe alpha3
        if (1 === preg_match('/^[a-zA-Z]{3}$/', $value)) {
            try {
                $data = $iso->alpha3($value);

                return $data[$this->returnKey];
            } catch (Throwable $e) {
            }
        }

        // maybe numeric
        if (1 === preg_match('/^[0-9]{3}$/', $value)) {
            try {
                $data = $iso->numeric($value);

                return $data[$this->returnKey];
            } catch (Throwable $e) {
            }
        }

        // last try by name string exact match
        try {
            $data = $iso->name($value);

            return $data[$this->returnKey];
        } catch (Throwable $e) {
        }

        return $value;
    }
}