<?php

namespace EP\EpTheme\Middleware;

use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\MiddlewareInterface;
use Psr\Http\Server\RequestHandlerInterface;
use TYPO3\CMS\Core\Exception\SiteNotFoundException;
use TYPO3\CMS\Core\Site\SiteFinder;
use TYPO3\CMS\Frontend\Authentication\FrontendUserAuthentication;

/**
 * Links to a form page carry the uid of the page they come from (?ref=123, e.g. the enquiry
 * button of a product page). Its URL is kept in the session until AddReferrerFinisher puts it
 * into the submission. On static pages the parameter reaches TYPO3 with the request that loads
 * the form (see the form placeholder of the static export).
 */
class ReferrerMiddleware implements MiddlewareInterface
{
    public const SESSION_KEY = 'referrer';

    public function __construct(private readonly SiteFinder $siteFinder) {}

    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
    {
        $ref = $request->getQueryParams()['ref'] ?? null;
        $frontendUser = $request->getAttribute('frontend.user');

        if (!is_numeric($ref) || !$frontendUser instanceof FrontendUserAuthentication) {
            return $handler->handle($request);
        }

        try {
            $url = (string)$this->siteFinder->getSiteByPageId((int)$ref)->getRouter()->generateUri((int)$ref);
            $frontendUser->setKey('ses', self::SESSION_KEY, $url);
            $frontendUser->storeSessionData();
        } catch (SiteNotFoundException) {
        }

        return $handler->handle($request);
    }
}