CIMChat::JoinParent

public function JoinParent($chatId, $messageId)
{
	$chatId = intval($chatId);
	if ($chatId <= 0)
	{
		$GLOBALS["APPLICATION"]->ThrowException(GetMessage("IM_ERROR_EMPTY_CHAT_ID"), "EMPTY_CHAT_ID");
		return false;
	}

	$messageId = intval($messageId);
	if ($messageId <= 0)
	{
		$GLOBALS["APPLICATION"]->ThrowException(GetMessage("IM_ERROR_EMPTY_CHAT_ID"), "EMPTY_CHAT_ID");
		return false;
	}

	$CIMMessage = new CIMMessage($this->user_id);
	$message = $CIMMessage->GetMessage($messageId, true);
	if (!$message)
	{
		$GLOBALS["APPLICATION"]->ThrowException(GetMessage("IM_ERROR_ACCESS_JOIN"), "ACCESS_JOIN");
		return false;
	}

	$relations = IMChat::getRelation($chatId, ['WITHOUT_COUNTERS' => 'Y']);
	if (!isset($relations[$this->user_id]))
	{
		$chat = new CIMChat(0);
		$chat->AddUser($chatId, $this->user_id);
	}

	return true;
}