FormLanding::getSiteId

public function getSiteId(): ?int
{
	if (!$this->canUse())
	{
		return null;
	}

	if ($this->siteId !== false)
	{
		return $this->siteId;
	}

	$this->siteId = null;
	$storedSiteId = (int) Main\Config\Option::get(
		'crm', $this::OPT_CODE_LANDINGS_SITE_ID
	);
	// site is not exist, create new one
	if (!$storedSiteId)
	{
		Rights::setGlobalOff();
		$res = \Bitrix\Landing\Site::add([
			'TITLE' => 'CRM Forms',
			'TYPE' => $this::SITE_TYPE,
			'CODE' => \Bitrix\Landing\Site\Type::PSEUDO_SCOPE_CODE_FORMS,
			'SPECIAL' => 'Y'
		]);
		Rights::setGlobalOn();
		if ($res->isSuccess())
		{
			$this->siteId = (int) $res->getId();
			Main\Config\Option::set(
				'crm', $this::OPT_CODE_LANDINGS_SITE_ID, $this->siteId
			);
			return $this->siteId;
		}
		else
		{
			$this->setErrorMessage($res->getErrors()[0]);
		}
	}

	if ($storedSiteId)
	{
		$this->siteId = $storedSiteId;
	}
	// check that exists
	if ($this->siteId)
	{
		$res = \Bitrix\Landing\Site::getList([
			'select' => [
				'ID'
			],
			'filter' => [
				'=ID' => $this->siteId,
				'CHECK_PERMISSIONS' => 'N'
			]
		]);
		if (!$res->fetch())
		{
			Main\Config\Option::set(
				'crm', $this::OPT_CODE_LANDINGS_SITE_ID, 0
			);
			$this->siteId = false;
			return $this->getSiteId();
		}
	}

	return $this->siteId;
}