<?php

namespace EP\EpTheme\Form;

use EP\EpTheme\Middleware\ReferrerMiddleware;
use TYPO3\CMS\Core\Routing\PageArguments;
use TYPO3\CMS\Core\Site\Entity\Site;
use TYPO3\CMS\Form\Domain\Finishers\AbstractFinisher;
use TYPO3\CMS\Frontend\Authentication\FrontendUserAuthentication;

/**
 * Adds the URL of the form's page and, if known, the page the visitor came from (see
 * ReferrerMiddleware) to the submission, so the e-mail finishers include them.
 */
class AddReferrerFinisher extends AbstractFinisher
{
    protected function executeInternal()
    {
        $this->addCurrentUrlField();
        $this->addReferrerField();
    }

    private function addReferrerField(): void
    {
        $frontendUser = $this->finisherContext->getRequest()->getAttribute('frontend.user');
        if (!$frontendUser instanceof FrontendUserAuthentication) {
            return;
        }

        $referrer = $frontendUser->getKey('ses', ReferrerMiddleware::SESSION_KEY);
        if (null === $referrer) {
            return;
        }

        $this->addField('referrer', 'Referrer', $referrer);

        $frontendUser->setKey('ses', ReferrerMiddleware::SESSION_KEY, null);
        $frontendUser->storeSessionData();
    }

    private function addCurrentUrlField(): void
    {
        $request = $this->finisherContext->getRequest();
        $routing = $request->getAttribute('routing');
        $site = $request->getAttribute('site');
        if (!$routing instanceof PageArguments || !$site instanceof Site) {
            return;
        }

        // The page itself, not the form page type the submission was posted to
        $url = (string)$site->getRouter()->generateUri($routing->getPageId(), [
            '_language' => $request->getAttribute('language'),
        ]);
        $this->addField('pageurl', 'URL', $url);
    }

    private function addField(string $identifier, string $label, string $value): void
    {
        $field = $this->finisherContext
            ->getFormRuntime()
            ->getFormDefinition()
            ->getPageByIndex(0)
            ->createElement($identifier, 'Text');

        $field->setDefaultValue($value);
        $field->setDataType('string');
        $field->setLabel($label);

        // Finisher variable for potential later use
        $this->finisherContext->getFinisherVariableProvider()->add(
            $this->shortFinisherIdentifier,
            $identifier,
            $value
        );
    }
}