<?php
declare(strict_types=1);

function pnpaas_traefik_labels(?string $domain, string $containerName): array
{
    $domain = strtolower(trim((string)$domain));
    if ($domain === '') {
        return [];
    }
    if (strlen($domain) > 253 || !preg_match('/^(?=.{1,253}$)(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?$/', $domain)) {
        throw new InvalidArgumentException('Die Kundendomain ist kein gültiger FQDN.');
    }

    $routerName = strtolower(trim((string)preg_replace('/[^a-z0-9-]+/i', '-', $containerName), '-'));
    if ($routerName === '' || strlen($routerName) > 63) {
        throw new InvalidArgumentException('Der Instanzname kann nicht als Traefik-Router verwendet werden.');
    }

    return [
        'traefik.enable' => 'true',
        'traefik.docker.network' => 'traefik-public',
        'traefik.http.routers.' . $routerName . '.rule' => 'Host(`' . $domain . '`)',
        'traefik.http.routers.' . $routerName . '.entrypoints' => 'websecure',
        'traefik.http.routers.' . $routerName . '.tls' => 'true',
        'traefik.http.routers.' . $routerName . '.tls.certresolver' => 'le',
        'traefik.http.services.' . $routerName . '.loadbalancer.server.port' => '30000',
    ];
}