StartIdFilter.php

<?php
 
namespace Bitrix\Im\V2\Controller\Filter;
 
use Bitrix\Im\V2\Message;
use Bitrix\Im\V2\MessageCollection;
use Bitrix\Main\Engine\ActionFilter\Base;
use Bitrix\Main\Event;
use Bitrix\Main\EventResult;
 
class StartIdFilter extends Base
{
    public function onBeforeAction(Event $event)
    {
        foreach ($this->getAction()->getArguments() as $argument)
        {
            if ($argument instanceof Message)
            {
                if (!$argument->getId())
                {
                    return null;
                }
 
                if ($argument->getId() < $argument->getChat()->getStartId())
                {
                    $this->addError(new Message\MessageError(Message\MessageError::MESSAGE_ACCESS_ERROR));
 
                    return new EventResult(EventResult::ERROR, null, null, $this);
                }
            }
 
            if ($argument instanceof MessageCollection)
            {
                $messages = $argument;
                $this->filterMessagesByStartId($messages);
                if ($messages->count() === 0)
                {
                    $this->addError(new Message\MessageError(Message\MessageError::MESSAGE_ACCESS_ERROR));
 
                    return new EventResult(EventResult::ERROR, null, null, $this);
                }
            }
        }
 
        return null;
    }
 
    private function filterMessagesByStartId(MessageCollection $messages): void
    {
        $keysToUnset = [];
 
        foreach ($messages as $key => $message)
        {
            if ($message->getMessageId() && $message->getMessageId() < $message->getChat()->getStartId())
            {
                $keysToUnset[$key] = $key;
            }
        }
 
        $messages->unsetByKeys($keysToUnset);
    }
}