TenantAtlas/app/Support/Baselines/BaselineSubjectKey.php

<?php

declare(strict_types=1);

namespace App\Support\Baselines;

final class BaselineSubjectKey
{
    public static function fromDisplayName(?string $displayName): ?string
    {
        if (! is_string($displayName)) {
            return null;
        }

        $trimmed = trim($displayName);

        if ($trimmed === '') {
            return null;
        }

        $collapsed = preg_replace('/\\s+/u', ' ', $trimmed);
        $collapsed = is_string($collapsed) ? $collapsed : $trimmed;

        $normalized = mb_strtolower($collapsed);
        $normalized = trim($normalized);

        return $normalized !== '' ? $normalized : null;
    }

    public static function workspaceSafeSubjectExternalId(string $policyType, string $subjectKey): string
    {
        return hash('sha256', $policyType.'|'.$subjectKey);
    }
}