<?php

declare(strict_types=1);

namespace PhpQml\Bridge;

use Symfony\Component\Mercure\HubInterface;
use Symfony\Component\Mercure\Update;

/**
 * Default implementation of {@see PublisherInterface}: a thin wrapper over
 * `symfony/mercure`'s `HubInterface` that JSON-encodes the envelope and
 * forwards the publish.
 *
 * Topic conventions and envelope shape are defined in PLAN.md §4.
 * Application code should typehint `PublisherInterface` instead of this
 * concrete class so swappable implementations (offline buffer, multi-hub
 * fan-out) remain a non-breaking change.
 */
final readonly class Publisher implements PublisherInterface
{
    public function __construct(
        private HubInterface $hub,
    ) {
    }

    public function publish(string $topic, array $envelope, bool $private = false): string
    {
        return $this->hub->publish(new Update(
            $topic,
            json_encode($envelope, \JSON_THROW_ON_ERROR),
            $private,
        ));
    }
}