CalendarType.php

<?php
 
namespace Bitrix\Im\V2\Chat\EntityLink;
 
use Bitrix\Im\V2\Chat\EntityLink;
use Bitrix\Main\Loader;
use Bitrix\Main\Web\Uri;
 
class CalendarType extends EntityLink
{
    protected const HAS_URL = true;
 
    protected function getUrl(): string
    {
        if (!Loader::includeModule('calendar'))
        {
            return '';
        }
 
        $uri = new Uri(\CCalendar::GetPathForCalendarEx($this->getContext()->getUserId()));
        $uri->addParams(['EVENT_ID' => $this->entityId]);
        $url = $uri->getUri();
 
        return $url;
    }
}