Method doExecute

/**
 * Internal function to execute the command.
 *
 * @param   InputInterface   $input   The input to inject into the command.
 * @param   OutputInterface  $output  The output to inject into the command.
 *
 * @return  integer  The command exit code
 *
 * @since   4.0.0
 */
protected function doExecute(InputInterface $input, OutputInterface $output) : int
{
    $this->configureIO($input, $output);
    $this->ioStyle->title('Delete users');
    $this->username = $this->getStringFromOption('username', 'Please enter a username');
    $userId = UserHelper::getUserId($this->username);
    $db = Factory::getDbo();
    if (empty($userId)) {
        $this->ioStyle->error($this->username . ' does not exist!');
        return Command::FAILURE;
    }
    if ($input->isInteractive() && !$this->ioStyle->confirm('Are you sure you want to delete this user?', false)) {
        $this->ioStyle->note('User not deleted');
        return Command::SUCCESS;
    }
    $groups = UserHelper::getUserGroups($userId);
    $user = User::getInstance($userId);
    if ($user->block == 0) {
        foreach ($groups as $groupId) {
            if (Access::checkGroup($groupId, 'core.admin')) {
                $queryUser = $db->getQuery(true);
                $queryUser->select('COUNT(*)')->from($db->quoteName('#__users', 'u'))->leftJoin($db->quoteName('#__user_usergroup_map', 'g'), '(' . $db->quoteName('u.id') . ' = ' . $db->quoteName('g.user_id') . ')')->where($db->quoteName('g.group_id') . " = :groupId")->where($db->quoteName('u.block') . " = 0")->bind(':groupId', $groupId, ParameterType::INTEGER);
                $db->setQuery($queryUser);
                $activeSuperUser = $db->loadResult();
                if ($activeSuperUser < 2) {
                    $this->ioStyle->error("You can't delete the last active Super User");
                    return Command::FAILURE;
                }
            }
        }
    }
    // Trigger delete of user
    $result = $user->delete();
    if (!$result) {
        $this->ioStyle->error("Can't remove " . $this->username . ' from usertable');
        return Command::FAILURE;
    }
    $this->ioStyle->success('User ' . $this->username . ' deleted!');
    return Command::SUCCESS;
}