CIMNotify::updateStateAfterDelete

static function updateStateAfterDelete(int $chatId, int $userId, bool $needToUpdateRecent): void
{
	global $DB;
	CIMMessenger::SpeedFileDelete($userId, IM_SPEED_NOTIFY);

	// update total amount of notifications
	$date = new DateTime();
	$date->add('-60 days'); // sync with BitrixImNotify::cleanNotifyAgent
	$messageCount = BitrixImModelMessageTable::getList([
		'select' => ['CNT'],
		'filter' => [
			'=CHAT_ID' => $chatId,
			'>DATE_CREATE' => $date
		],
		'runtime' => [
			new BitrixMainORMFieldsExpressionField('CNT', 'COUNT(*)')
		]
	])->fetch();

	IMModelChatTable::update($chatId, [
		'MESSAGE_COUNT' => $messageCount['CNT'],
	]);

	// update the preview of last message in recent list
	if ($needToUpdateRecent)
	{
		$ormParams = [
			'select' => ['ID'],
			'filter' => [
				'=CHAT_ID' => $chatId,
			],
			'order' => ['DATE_CREATE' => 'DESC'],
			'limit' => 1,
		];
		$lastNotification = BitrixImModelMessageTable::getRow($ormParams);
		if ($lastNotification !== null)
		{
			$DB->Query("
				UPDATE b_im_recent 
					SET ITEM_MID = {$lastNotification['ID']}
				WHERE
					USER_ID = {$userId}
				AND
					ITEM_TYPE = 'S'
				AND
					ITEM_ID = {$userId}
			");
		}
	}
}