26      * @param string $user
29     public function getUserGroups($user)  argument
32         return $config[$user] ?? [];
45         foreach ($config as $user => $groups) {
47                 $users[] = $user;
63         foreach ($config as $user => $usergroups) {
68                 $groups[$group][] = $user;
80      * @param string $user
83     public function removeUser($user)  argument
86         if (isset($config[$user])) unset($config[$user]);
93      * @param string $user
97     public function addGroupsToUser($user, $groups)  argument
100         if (!isset($config[$user])) {
101             $config[$user] = [];
103         $config[$user] = array_filter(array_unique(array_merge($config[$user], $groups)));
110      * @param string $user
114     public function setUserGroups($user, $groups)  argument
117         $config[$user] = array_filter($groups);
118         if ($config[$user] === []) {
119             unset($config[$user]);
133         foreach ($config as $user => $groups) {
135                 unset($config[$user][$key]);
151         foreach ($users as $user) {
152             if (!isset($config[$user])) {
153                 $config[$user] = [];
155             $config[$user][] = $group;
156             $config[$user] = array_filter(array_unique($config[$user]));
164         foreach ($users as $user) {
165             if (!isset($config[$user])) {
166                 $config[$user] = [];
168             $config[$user][] = $group;
169             $config[$user] = array_filter(array_unique($config[$user]));
170             if ($config[$user] === []) {
171                 unset($config[$user]);
193             $user = rawurldecode($key);
195             $config[$user] = $groups;
216         foreach ($config as $user => $groups) {
217             $lines[] = auth_nameencode($user) . "\t" .