SlugRule.php

<?php

declare(strict_types=1);

namespace KaririCode\Sanitizer\Rule\String;

use KaririCode\Sanitizer\Contract\SanitizationContext;
use KaririCode\Sanitizer\Contract\SanitizationRule;

/**
 * Converts a string to a URL-safe slug.
 *
 * Transliterates common accented characters, lowercases,
 * replaces non-alphanumeric with hyphens, collapses multiple hyphens.
 *
 * @author  Walmir Silva <walmir.silva@kariricode.org>
 *
 * @since   3.1.0 ARFA 1.3
 */
final readonly class SlugRule implements SanitizationRule
{
    #[\Override]
    public function sanitize(mixed $value, SanitizationContext $context): mixed
    {
        if (! \is_string($value)) {
            return $value;
        }

        $separatorRaw = $context->getParameter('separator', '-');
        $separator = \is_string($separatorRaw) ? $separatorRaw : '-';

        // Transliterate common accented characters
        $slug = $this->transliterate($value);
        $slug = mb_strtolower($slug, 'UTF-8');
        $slug = preg_replace('/[^a-z0-9]+/', $separator, $slug) ?? $slug;
        $slug = trim($slug, $separator);

        return $slug;
    }

    #[\Override]
    public function getName(): string
    {
        return 'string.slug';
    }

    private function transliterate(string $value): string
    {
        $map = [
            'á' => 'a', 'à' => 'a', 'ã' => 'a', 'â' => 'a', 'ä' => 'a',
            'é' => 'e', 'è' => 'e', 'ê' => 'e', 'ë' => 'e',
            'í' => 'i', 'ì' => 'i', 'î' => 'i', 'ï' => 'i',
            'ó' => 'o', 'ò' => 'o', 'õ' => 'o', 'ô' => 'o', 'ö' => 'o',
            'ú' => 'u', 'ù' => 'u', 'û' => 'u', 'ü' => 'u',
            'ç' => 'c', 'ñ' => 'n', 'ß' => 'ss',
            'Á' => 'A', 'À' => 'A', 'Ã' => 'A', 'Â' => 'A', 'Ä' => 'A',
            'É' => 'E', 'È' => 'E', 'Ê' => 'E', 'Ë' => 'E',
            'Í' => 'I', 'Ì' => 'I', 'Î' => 'I', 'Ï' => 'I',
            'Ó' => 'O', 'Ò' => 'O', 'Õ' => 'O', 'Ô' => 'O', 'Ö' => 'O',
            'Ú' => 'U', 'Ù' => 'U', 'Û' => 'U', 'Ü' => 'U',
            'Ç' => 'C', 'Ñ' => 'N',
        ];

        return strtr($value, $map);
    }
}