gnu-social/components/Collection/Util/Controller/FeedController.php

<?php

declare(strict_types = 1);

// {{{ License
// This file is part of GNU social - https://www.gnu.org/software/social
//
// GNU social is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// GNU social is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with GNU social.  If not, see <http://www.gnu.org/licenses/>.
// }}}

/**
 * Base class for feed controllers
 *
 * @package  GNUsocial
 * @category Controller
 *
 * @author    Hugo Sales <hugo@hsal.es>
 * @copyright 2021 Free Software Foundation, Inc http://www.fsf.org
 * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
 */

namespace Component\Collection\Util\Controller;

use App\Core\Event;
use App\Entity\Actor;
use App\Entity\Note;
use App\Util\Common;
use Functional as F;

/**
 * @template T
 *
 * @extends OrderedCollection<T>
 */
abstract class FeedController extends OrderedCollection
{
    /**
     * Post-processing of the result of a feed controller, to remove any
     * notes or actors the user specified, as well as format the raw
     * list of notes into a usable format
     *
     * @template NA of Note|Actor
     *
     * @param NA[] $result
     *
     * @return NA[]
     */
    protected function postProcess(array $result): array
    {
        $actor = Common::actor();
        if (\array_key_exists('notes', $result)) {
            $notes = $result['notes'];
            self::enforceScope($notes, $actor, $result['actor'] ?? null);
            Event::handle('FilterNoteList', [$actor, &$notes, $result['request']]);
            Event::handle('FormatNoteList', [$notes, &$result['notes'], &$result['request']]);
        }

        return $result;
    }

    /**
     * @param Note[] $notes
     */
    private static function enforceScope(array &$notes, ?Actor $actor, ?Actor $in = null): void
    {
        $notes = F\select($notes, fn (Note $n) => $n->isVisibleTo($actor, $in));
    }
}