includes/specials/SpecialUserrights.php

   1 <?php
   2 /**
   3  * Implements Special:Userrights
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup SpecialPage
  22  */
  23
  24 /**
  25  * Special page to allow managing user group membership
  26  *
  27  * @ingroup SpecialPage
  28  */
  29 class UserrightsPage extends SpecialPage {
  30         # The target of the local right-adjuster's interest.  Can be gotten from
  31         # either a GET parameter or a subpage-style parameter, so have a member
  32         # variable for it.
  33         protected $mTarget;
  34         /*
  35          * @var null|User $mFetchedUser The user object of the target username or null.
  36          */
  37         protected $mFetchedUser = null;
  38         protected $isself = false;
  39
  40         public function __construct() {
  41                 parent::__construct( 'Userrights' );
  42         }
  43
  44         public function doesWrites() {
  45                 return true;
  46         }
  47
  48         public function isRestricted() {
  49                 return true;
  50         }
  51
  52         public function userCanExecute( User $user ) {
  53                 return $this->userCanChangeRights( $user, false );
  54         }
  55
  56         /**
  57          * @param User $user
  58          * @param bool $checkIfSelf
  59          * @return bool
  60          */
  61         public function userCanChangeRights( $user, $checkIfSelf = true ) {
  62                 $available = $this->changeableGroups();
  63                 if ( $user->getId() == 0 ) {
  64                         return false;
  65                 }
  66
  67                 return !empty( $available['add'] )
  68                         || !empty( $available['remove'] )
  69                         || ( ( $this->isself || !$checkIfSelf ) &&
  70                                 ( !empty( $available['add-self'] )
  71                                         || !empty( $available['remove-self'] ) ) );
  72         }
  73
  74         /**
  75          * Manage forms to be shown according to posted data.
  76          * Depending on the submit button used, call a form or a save function.
  77          *
  78          * @param string|null $par String if any subpage provided, else null
  79          * @throws UserBlockedError|PermissionsError
  80          */
  81         public function execute( $par ) {
  82                 // If the visitor doesn't have permissions to assign or remove
  83                 // any groups, it's a bit silly to give them the user search prompt.
  84
  85                 $user = $this->getUser();
  86                 $request = $this->getRequest();
  87                 $out = $this->getOutput();
  88
  89                 /*
  90                  * If the user is blocked and they only have "partial" access
  91                  * (e.g. they don't have the userrights permission), then don't
  92                  * allow them to use Special:UserRights.
  93                  */
  94                 if ( $user->isBlocked() && !$user->isAllowed( 'userrights' ) ) {
  95                         throw new UserBlockedError( $user->getBlock() );
  96                 }
  97
  98                 if ( $par !== null ) {
  99                         $this->mTarget = $par;
 100                 } else {
 101                         $this->mTarget = $request->getVal( 'user' );
 102                 }
 103
 104                 $available = $this->changeableGroups();
 105
 106                 if ( $this->mTarget === null ) {
 107                         /*
 108                          * If the user specified no target, and they can only
 109                          * edit their own groups, automatically set them as the
 110                          * target.
 111                          */
 112                         if ( !count( $available['add'] ) && !count( $available['remove'] ) ) {
 113                                 $this->mTarget = $user->getName();
 114                         }
 115                 }
 116
 117                 if ( $this->mTarget !== null && User::getCanonicalName( $this->mTarget ) === $user->getName() ) {
 118                         $this->isself = true;
 119                 }
 120
 121                 $fetchedStatus = $this->fetchUser( $this->mTarget );
 122                 if ( $fetchedStatus->isOK() ) {
 123                         $this->mFetchedUser = $fetchedStatus->value;
 124                         if ( $this->mFetchedUser instanceof User ) {
 125                                 // Set the 'relevant user' in the skin, so it displays links like Contributions,
 126                                 // User logs, UserRights, etc.
 127                                 $this->getSkin()->setRelevantUser( $this->mFetchedUser );
 128                         }
 129                 }
 130
 131                 if ( !$this->userCanChangeRights( $user, true ) ) {
 132                         if ( $this->isself && $request->getCheck( 'success' ) ) {
 133                                 // bug 48609: if the user just removed its own rights, this would
 134                                 // leads it in a "permissions error" page. In that case, show a
 135                                 // message that it can't anymore use this page instead of an error
 136                                 $this->setHeaders();
 137                                 $out->wrapWikiMsg( "<div class=\"successbox\">\n$1\n</div>", 'userrights-removed-self' );
 138                                 $out->returnToMain();
 139
 140                                 return;
 141                         }
 142
 143                         // @todo FIXME: There may be intermediate groups we can mention.
 144                         $msg = $user->isAnon() ? 'userrights-nologin' : 'userrights-notallowed';
 145                         throw new PermissionsError( null, [ [ $msg ] ] );
 146                 }
 147
 148                 // show a successbox, if the user rights was saved successfully
 149                 if ( $request->getCheck( 'success' ) && $this->mFetchedUser !== null ) {
 150                         $out->wrapWikiMsg(
 151                                 "<div class=\"successbox\">\n$1\n</div>",
 152                                 [ 'savedrights', $this->mFetchedUser->getName() ]
 153                         );
 154                 }
 155
 156                 $this->checkReadOnly();
 157
 158                 $this->setHeaders();
 159                 $this->outputHeader();
 160
 161                 $out->addModuleStyles( 'mediawiki.special' );
 162                 $this->addHelpLink( 'Help:Assigning permissions' );
 163
 164                 // show the general form
 165                 if ( count( $available['add'] ) || count( $available['remove'] ) ) {
 166                         $this->switchForm();
 167                 }
 168
 169                 if (
 170                         $request->wasPosted() &&
 171                         $request->getCheck( 'saveusergroups' ) &&
 172                         $this->mTarget !== null &&
 173                         $user->matchEditToken( $request->getVal( 'wpEditToken' ), $this->mTarget )
 174                 ) {
 175                         // save settings
 176                         if ( !$fetchedStatus->isOK() ) {
 177                                 $this->getOutput()->addWikiText( $fetchedStatus->getWikiText() );
 178
 179                                 return;
 180                         }
 181
 182                         $targetUser = $this->mFetchedUser;
 183                         if ( $targetUser instanceof User ) { // UserRightsProxy doesn't have this method (bug 61252)
 184                                 $targetUser->clearInstanceCache(); // bug 38989
 185                         }
 186
 187                         if ( $request->getVal( 'conflictcheck-originalgroups' )
 188                                 !== implode( ',', $targetUser->getGroups() )
 189                         ) {
 190                                 $out->addWikiMsg( 'userrights-conflict' );
 191                         } else {
 192                                 $this->saveUserGroups(
 193                                         $this->mTarget,
 194                                         $request->getVal( 'user-reason' ),
 195                                         $targetUser
 196                                 );
 197
 198                                 $out->redirect( $this->getSuccessURL() );
 199
 200                                 return;
 201                         }
 202                 }
 203
 204                 // show some more forms
 205                 if ( $this->mTarget !== null ) {
 206                         $this->editUserGroupsForm( $this->mTarget );
 207                 }
 208         }
 209
 210         function getSuccessURL() {
 211                 return $this->getPageTitle( $this->mTarget )->getFullURL( [ 'success' => 1 ] );
 212         }
 213
 214         /**
 215          * Save user groups changes in the database.
 216          * Data comes from the editUserGroupsForm() form function
 217          *
 218          * @param string $username Username to apply changes to.
 219          * @param string $reason Reason for group change
 220          * @param User|UserRightsProxy $user Target user object.
 221          * @return null
 222          */
 223         function saveUserGroups( $username, $reason, $user ) {
 224                 $allgroups = $this->getAllGroups();
 225                 $addgroup = [];
 226                 $removegroup = [];
 227
 228                 // This could possibly create a highly unlikely race condition if permissions are changed between
 229                 //  when the form is loaded and when the form is saved. Ignoring it for the moment.
 230                 foreach ( $allgroups as $group ) {
 231                         // We'll tell it to remove all unchecked groups, and add all checked groups.
 232                         // Later on, this gets filtered for what can actually be removed
 233                         if ( $this->getRequest()->getCheck( "wpGroup-$group" ) ) {
 234                                 $addgroup[] = $group;
 235                         } else {
 236                                 $removegroup[] = $group;
 237                         }
 238                 }
 239
 240                 $this->doSaveUserGroups( $user, $addgroup, $removegroup, $reason );
 241         }
 242
 243         /**
 244          * Save user groups changes in the database.
 245          *
 246          * @param User|UserRightsProxy $user
 247          * @param array $add Array of groups to add
 248          * @param array $remove Array of groups to remove
 249          * @param string $reason Reason for group change
 250          * @return array Tuple of added, then removed groups
 251          */
 252         function doSaveUserGroups( $user, $add, $remove, $reason = '' ) {
 253                 global $wgAuth;
 254
 255                 // Validate input set...
 256                 $isself = $user->getName() == $this->getUser()->getName();
 257                 $groups = $user->getGroups();
 258                 $changeable = $this->changeableGroups();
 259                 $addable = array_merge( $changeable['add'], $isself ? $changeable['add-self'] : [] );
 260                 $removable = array_merge( $changeable['remove'], $isself ? $changeable['remove-self'] : [] );
 261
 262                 $remove = array_unique(
 263                         array_intersect( (array)$remove, $removable, $groups ) );
 264                 $add = array_unique( array_diff(
 265                         array_intersect( (array)$add, $addable ),
 266                         $groups )
 267                 );
 268
 269                 $oldGroups = $user->getGroups();
 270                 $newGroups = $oldGroups;
 271
 272                 // Remove then add groups
 273                 if ( $remove ) {
 274                         foreach ( $remove as $index => $group ) {
 275                                 if ( !$user->removeGroup( $group ) ) {
 276                                         unset( $remove[$index] );
 277                                 }
 278                         }
 279                         $newGroups = array_diff( $newGroups, $remove );
 280                 }
 281                 if ( $add ) {
 282                         foreach ( $add as $index => $group ) {
 283                                 if ( !$user->addGroup( $group ) ) {
 284                                         unset( $add[$index] );
 285                                 }
 286                         }
 287                         $newGroups = array_merge( $newGroups, $add );
 288                 }
 289                 $newGroups = array_unique( $newGroups );
 290
 291                 // Ensure that caches are cleared
 292                 $user->invalidateCache();
 293
 294                 // update groups in external authentication database
 295                 Hooks::run( 'UserGroupsChanged', [ $user, $add, $remove, $this->getUser(), $reason ] );
 296                 $wgAuth->updateExternalDBGroups( $user, $add, $remove );
 297
 298                 wfDebug( 'oldGroups: ' . print_r( $oldGroups, true ) . "\n" );
 299                 wfDebug( 'newGroups: ' . print_r( $newGroups, true ) . "\n" );
 300                 // Deprecated in favor of UserGroupsChanged hook
 301                 Hooks::run( 'UserRights', [ &$user, $add, $remove ], '1.26' );
 302
 303                 if ( $newGroups != $oldGroups ) {
 304                         $this->addLogEntry( $user, $oldGroups, $newGroups, $reason );
 305                 }
 306
 307                 return [ $add, $remove ];
 308         }
 309
 310         /**
 311          * Add a rights log entry for an action.
 312          * @param User $user
 313          * @param array $oldGroups
 314          * @param array $newGroups
 315          * @param array $reason
 316          */
 317         function addLogEntry( $user, $oldGroups, $newGroups, $reason ) {
 318                 $logEntry = new ManualLogEntry( 'rights', 'rights' );
 319                 $logEntry->setPerformer( $this->getUser() );
 320                 $logEntry->setTarget( $user->getUserPage() );
 321                 $logEntry->setComment( $reason );
 322                 $logEntry->setParameters( [
 323                         '4::oldgroups' => $oldGroups,
 324                         '5::newgroups' => $newGroups,
 325                 ] );
 326                 $logid = $logEntry->insert();
 327                 $logEntry->publish( $logid );
 328         }
 329
 330         /**
 331          * Edit user groups membership
 332          * @param string $username Name of the user.
 333          */
 334         function editUserGroupsForm( $username ) {
 335                 $status = $this->fetchUser( $username );
 336                 if ( !$status->isOK() ) {
 337                         $this->getOutput()->addWikiText( $status->getWikiText() );
 338
 339                         return;
 340                 } else {
 341                         $user = $status->value;
 342                 }
 343
 344                 $groups = $user->getGroups();
 345
 346                 $this->showEditUserGroupsForm( $user, $groups );
 347
 348                 // This isn't really ideal logging behavior, but let's not hide the
 349                 // interwiki logs if we're using them as is.
 350                 $this->showLogFragment( $user, $this->getOutput() );
 351         }
 352
 353         /**
 354          * Normalize the input username, which may be local or remote, and
 355          * return a user (or proxy) object for manipulating it.
 356          *
 357          * Side effects: error output for invalid access
 358          * @param string $username
 359          * @return Status
 360          */
 361         public function fetchUser( $username ) {
 362                 $parts = explode( $this->getConfig()->get( 'UserrightsInterwikiDelimiter' ), $username );
 363                 if ( count( $parts ) < 2 ) {
 364                         $name = trim( $username );
 365                         $database = '';
 366                 } else {
 367                         list( $name, $database ) = array_map( 'trim', $parts );
 368
 369                         if ( $database == wfWikiID() ) {
 370                                 $database = '';
 371                         } else {
 372                                 if ( !$this->getUser()->isAllowed( 'userrights-interwiki' ) ) {
 373                                         return Status::newFatal( 'userrights-no-interwiki' );
 374                                 }
 375                                 if ( !UserRightsProxy::validDatabase( $database ) ) {
 376                                         return Status::newFatal( 'userrights-nodatabase', $database );
 377                                 }
 378                         }
 379                 }
 380
 381                 if ( $name === '' ) {
 382                         return Status::newFatal( 'nouserspecified' );
 383                 }
 384
 385                 if ( $name[0] == '#' ) {
 386                         // Numeric ID can be specified...
 387                         // We'll do a lookup for the name internally.
 388                         $id = intval( substr( $name, 1 ) );
 389
 390                         if ( $database == '' ) {
 391                                 $name = User::whoIs( $id );
 392                         } else {
 393                                 $name = UserRightsProxy::whoIs( $database, $id );
 394                         }
 395
 396                         if ( !$name ) {
 397                                 return Status::newFatal( 'noname' );
 398                         }
 399                 } else {
 400                         $name = User::getCanonicalName( $name );
 401                         if ( $name === false ) {
 402                                 // invalid name
 403                                 return Status::newFatal( 'nosuchusershort', $username );
 404                         }
 405                 }
 406
 407                 if ( $database == '' ) {
 408                         $user = User::newFromName( $name );
 409                 } else {
 410                         $user = UserRightsProxy::newFromName( $database, $name );
 411                 }
 412
 413                 if ( !$user || $user->isAnon() ) {
 414                         return Status::newFatal( 'nosuchusershort', $username );
 415                 }
 416
 417                 return Status::newGood( $user );
 418         }
 419
 420         /**
 421          * @since 1.15
 422          *
 423          * @param array $ids
 424          *
 425          * @return string
 426          */
 427         public function makeGroupNameList( $ids ) {
 428                 if ( empty( $ids ) ) {
 429                         return $this->msg( 'rightsnone' )->inContentLanguage()->text();
 430                 } else {
 431                         return implode( ', ', $ids );
 432                 }
 433         }
 434
 435         /**
 436          * Output a form to allow searching for a user
 437          */
 438         function switchForm() {
 439                 $this->getOutput()->addModules( 'mediawiki.userSuggest' );
 440
 441                 $this->getOutput()->addHTML(
 442                         Html::openElement(
 443                                 'form',
 444                                 [
 445                                         'method' => 'get',
 446                                         'action' => wfScript(),
 447                                         'name' => 'uluser',
 448                                         'id' => 'mw-userrights-form1'
 449                                 ]
 450                         ) .
 451                         Html::hidden( 'title', $this->getPageTitle()->getPrefixedText() ) .
 452                         Xml::fieldset( $this->msg( 'userrights-lookup-user' )->text() ) .
 453                         Xml::inputLabel(
 454                                 $this->msg( 'userrights-user-editname' )->text(),
 455                                 'user',
 456                                 'username',
 457                                 30,
 458                                 str_replace( '_', ' ', $this->mTarget ),
 459                                 [
 460                                         'class' => 'mw-autocomplete-user', // used by mediawiki.userSuggest
 461                                 ] + (
 462                                         // Set autofocus on blank input and error input
 463                                         $this->mFetchedUser === null ? [ 'autofocus' => '' ] : []
 464                                 )
 465                         ) . ' ' .
 466                         Xml::submitButton(
 467                                 $this->msg(
 468                                         'editusergroup',
 469                                         $this->mFetchedUser === null ? '[]' : $this->mFetchedUser->getName()
 470                                 )->text()
 471                         ) .
 472                         Html::closeElement( 'fieldset' ) .
 473                         Html::closeElement( 'form' ) . "\n"
 474                 );
 475         }
 476
 477         /**
 478          * Go through used and available groups and return the ones that this
 479          * form will be able to manipulate based on the current user's system
 480          * permissions.
 481          *
 482          * @param array $groups List of groups the given user is in
 483          * @return array Tuple of addable, then removable groups
 484          */
 485         protected function splitGroups( $groups ) {
 486                 list( $addable, $removable, $addself, $removeself ) = array_values( $this->changeableGroups() );
 487
 488                 $removable = array_intersect(
 489                         array_merge( $this->isself ? $removeself : [], $removable ),
 490                         $groups
 491                 ); // Can't remove groups the user doesn't have
 492                 $addable = array_diff(
 493                         array_merge( $this->isself ? $addself : [], $addable ),
 494                         $groups
 495                 ); // Can't add groups the user does have
 496
 497                 return [ $addable, $removable ];
 498         }
 499
 500         /**
 501          * Show the form to edit group memberships.
 502          *
 503          * @param User|UserRightsProxy $user User or UserRightsProxy you're editing
 504          * @param array $groups Array of groups the user is in
 505          */
 506         protected function showEditUserGroupsForm( $user, $groups ) {
 507                 $list = [];
 508                 $membersList = [];
 509                 foreach ( $groups as $group ) {
 510                         $list[] = self::buildGroupLink( $group );
 511                         $membersList[] = self::buildGroupMemberLink( $group );
 512                 }
 513
 514                 $autoList = [];
 515                 $autoMembersList = [];
 516                 if ( $user instanceof User ) {
 517                         foreach ( Autopromote::getAutopromoteGroups( $user ) as $group ) {
 518                                 $autoList[] = self::buildGroupLink( $group );
 519                                 $autoMembersList[] = self::buildGroupMemberLink( $group );
 520                         }
 521                 }
 522
 523                 $language = $this->getLanguage();
 524                 $displayedList = $this->msg( 'userrights-groupsmember-type' )
 525                         ->rawParams(
 526                                 $language->listToText( $list ),
 527                                 $language->listToText( $membersList )
 528                         )->escaped();
 529                 $displayedAutolist = $this->msg( 'userrights-groupsmember-type' )
 530                         ->rawParams(
 531                                 $language->listToText( $autoList ),
 532                                 $language->listToText( $autoMembersList )
 533                         )->escaped();
 534
 535                 $grouplist = '';
 536                 $count = count( $list );
 537                 if ( $count > 0 ) {
 538                         $grouplist = $this->msg( 'userrights-groupsmember' )
 539                                 ->numParams( $count )
 540                                 ->params( $user->getName() )
 541                                 ->parse();
 542                         $grouplist = '<p>' . $grouplist . ' ' . $displayedList . "</p>\n";
 543                 }
 544
 545                 $count = count( $autoList );
 546                 if ( $count > 0 ) {
 547                         $autogrouplistintro = $this->msg( 'userrights-groupsmember-auto' )
 548                                 ->numParams( $count )
 549                                 ->params( $user->getName() )
 550                                 ->parse();
 551                         $grouplist .= '<p>' . $autogrouplistintro . ' ' . $displayedAutolist . "</p>\n";
 552                 }
 553
 554                 $userToolLinks = Linker::userToolLinks(
 555                         $user->getId(),
 556                         $user->getName(),
 557                         false, /* default for redContribsWhenNoEdits */
 558                         Linker::TOOL_LINKS_EMAIL /* Add "send e-mail" link */
 559                 );
 560
 561                 $this->getOutput()->addHTML(
 562                         Xml::openElement(
 563                                 'form',
 564                                 [
 565                                         'method' => 'post',
 566                                         'action' => $this->getPageTitle()->getLocalURL(),
 567                                         'name' => 'editGroup',
 568                                         'id' => 'mw-userrights-form2'
 569                                 ]
 570                         ) .
 571                         Html::hidden( 'user', $this->mTarget ) .
 572                         Html::hidden( 'wpEditToken', $this->getUser()->getEditToken( $this->mTarget ) ) .
 573                         Html::hidden(
 574                                 'conflictcheck-originalgroups',
 575                                 implode( ',', $user->getGroups() )
 576                         ) . // Conflict detection
 577                         Xml::openElement( 'fieldset' ) .
 578                         Xml::element(
 579                                 'legend',
 580                                 [],
 581                                 $this->msg( 'userrights-editusergroup', $user->getName() )->text()
 582                         ) .
 583                         $this->msg( 'editinguser' )->params( wfEscapeWikiText( $user->getName() ) )
 584                                 ->rawParams( $userToolLinks )->parse() .
 585                         $this->msg( 'userrights-groups-help', $user->getName() )->parse() .
 586                         $grouplist .
 587                         $this->groupCheckboxes( $groups, $user ) .
 588                         Xml::openElement( 'table', [ 'id' => 'mw-userrights-table-outer' ] ) .
 589                                 "<tr>
 590                                         <td class='mw-label'>" .
 591                                                 Xml::label( $this->msg( 'userrights-reason' )->text(), 'wpReason' ) .
 592                                         "</td>
 593                                         <td class='mw-input'>" .
 594                                                 Xml::input( 'user-reason', 60, $this->getRequest()->getVal( 'user-reason', false ),
 595                                                         [ 'id' => 'wpReason', 'maxlength' => 255 ] ) .
 596                                         "</td>
 597                                 </tr>
 598                                 <tr>
 599                                         <td></td>
 600                                         <td class='mw-submit'>" .
 601                                                 Xml::submitButton( $this->msg( 'saveusergroups', $user->getName() )->text(),
 602                                                         [ 'name' => 'saveusergroups' ] +
 603                                                                 Linker::tooltipAndAccesskeyAttribs( 'userrights-set' )
 604                                                 ) .
 605                                         "</td>
 606                                 </tr>" .
 607                         Xml::closeElement( 'table' ) . "\n" .
 608                         Xml::closeElement( 'fieldset' ) .
 609                         Xml::closeElement( 'form' ) . "\n"
 610                 );
 611         }
 612
 613         /**
 614          * Format a link to a group description page
 615          *
 616          * @param string $group
 617          * @return string
 618          */
 619         private static function buildGroupLink( $group ) {
 620                 return User::makeGroupLinkHTML( $group, User::getGroupName( $group ) );
 621         }
 622
 623         /**
 624          * Format a link to a group member description page
 625          *
 626          * @param string $group
 627          * @return string
 628          */
 629         private static function buildGroupMemberLink( $group ) {
 630                 return User::makeGroupLinkHTML( $group, User::getGroupMember( $group ) );
 631         }
 632
 633         /**
 634          * Returns an array of all groups that may be edited
 635          * @return array Array of groups that may be edited.
 636          */
 637         protected static function getAllGroups() {
 638                 return User::getAllGroups();
 639         }
 640
 641         /**
 642          * Adds a table with checkboxes where you can select what groups to add/remove
 643          *
 644          * @todo Just pass the username string?
 645          * @param array $usergroups Groups the user belongs to
 646          * @param User $user
 647          * @return string XHTML table element with checkboxes
 648          */
 649         private function groupCheckboxes( $usergroups, $user ) {
 650                 $allgroups = $this->getAllGroups();
 651                 $ret = '';
 652
 653                 // Put all column info into an associative array so that extensions can
 654                 // more easily manage it.
 655                 $columns = [ 'unchangeable' => [], 'changeable' => [] ];
 656
 657                 foreach ( $allgroups as $group ) {
 658                         $set = in_array( $group, $usergroups );
 659                         // Should the checkbox be disabled?
 660                         $disabled = !(
 661                                 ( $set && $this->canRemove( $group ) ) ||
 662                                 ( !$set && $this->canAdd( $group ) ) );
 663                         // Do we need to point out that this action is irreversible?
 664                         $irreversible = !$disabled && (
 665                                 ( $set && !$this->canAdd( $group ) ) ||
 666                                 ( !$set && !$this->canRemove( $group ) ) );
 667
 668                         $checkbox = [
 669                                 'set' => $set,
 670                                 'disabled' => $disabled,
 671                                 'irreversible' => $irreversible
 672                         ];
 673
 674                         if ( $disabled ) {
 675                                 $columns['unchangeable'][$group] = $checkbox;
 676                         } else {
 677                                 $columns['changeable'][$group] = $checkbox;
 678                         }
 679                 }
 680
 681                 // Build the HTML table
 682                 $ret .= Xml::openElement( 'table', [ 'class' => 'mw-userrights-groups' ] ) .
 683                         "<tr>\n";
 684                 foreach ( $columns as $name => $column ) {
 685                         if ( $column === [] ) {
 686                                 continue;
 687                         }
 688                         // Messages: userrights-changeable-col, userrights-unchangeable-col
 689                         $ret .= Xml::element(
 690                                 'th',
 691                                 null,
 692                                 $this->msg( 'userrights-' . $name . '-col', count( $column ) )->text()
 693                         );
 694                 }
 695
 696                 $ret .= "</tr>\n<tr>\n";
 697                 foreach ( $columns as $column ) {
 698                         if ( $column === [] ) {
 699                                 continue;
 700                         }
 701                         $ret .= "\t<td style='vertical-align:top;'>\n";
 702                         foreach ( $column as $group => $checkbox ) {
 703                                 $attr = $checkbox['disabled'] ? [ 'disabled' => 'disabled' ] : [];
 704
 705                                 $member = User::getGroupMember( $group, $user->getName() );
 706                                 if ( $checkbox['irreversible'] ) {
 707                                         $text = $this->msg( 'userrights-irreversible-marker', $member )->text();
 708                                 } else {
 709                                         $text = $member;
 710                                 }
 711                                 $checkboxHtml = Xml::checkLabel( $text, "wpGroup-" . $group,
 712                                         "wpGroup-" . $group, $checkbox['set'], $attr );
 713                                 $ret .= "\t\t" . ( $checkbox['disabled']
 714                                         ? Xml::tags( 'span', [ 'class' => 'mw-userrights-disabled' ], $checkboxHtml )
 715                                         : $checkboxHtml
 716                                 ) . "<br />\n";
 717                         }
 718                         $ret .= "\t</td>\n";
 719                 }
 720                 $ret .= Xml::closeElement( 'tr' ) . Xml::closeElement( 'table' );
 721
 722                 return $ret;
 723         }
 724
 725         /**
 726          * @param string $group The name of the group to check
 727          * @return bool Can we remove the group?
 728          */
 729         private function canRemove( $group ) {
 730                 // $this->changeableGroups()['remove'] doesn't work, of course. Thanks, PHP.
 731                 $groups = $this->changeableGroups();
 732
 733                 return in_array(
 734                         $group,
 735                         $groups['remove'] ) || ( $this->isself && in_array( $group, $groups['remove-self'] )
 736                 );
 737         }
 738
 739         /**
 740          * @param string $group The name of the group to check
 741          * @return bool Can we add the group?
 742          */
 743         private function canAdd( $group ) {
 744                 $groups = $this->changeableGroups();
 745
 746                 return in_array(
 747                         $group,
 748                         $groups['add'] ) || ( $this->isself && in_array( $group, $groups['add-self'] )
 749                 );
 750         }
 751
 752         /**
 753          * Returns $this->getUser()->changeableGroups()
 754          *
 755          * @return array Array(
 756          *   'add' => array( addablegroups ),
 757          *   'remove' => array( removablegroups ),
 758          *   'add-self' => array( addablegroups to self ),
 759          *   'remove-self' => array( removable groups from self )
 760          *  )
 761          */
 762         function changeableGroups() {
 763                 return $this->getUser()->changeableGroups();
 764         }
 765
 766         /**
 767          * Show a rights log fragment for the specified user
 768          *
 769          * @param User $user User to show log for
 770          * @param OutputPage $output OutputPage to use
 771          */
 772         protected function showLogFragment( $user, $output ) {
 773                 $rightsLogPage = new LogPage( 'rights' );
 774                 $output->addHTML( Xml::element( 'h2', null, $rightsLogPage->getName()->text() ) );
 775                 LogEventsList::showLogExtract( $output, 'rights', $user->getUserPage() );
 776         }
 777
 778         /**
 779          * Return an array of subpages beginning with $search that this special page will accept.
 780          *
 781          * @param string $search Prefix to search for
 782          * @param int $limit Maximum number of results to return (usually 10)
 783          * @param int $offset Number of results to skip (usually 0)
 784          * @return string[] Matching subpages
 785          */
 786         public function prefixSearchSubpages( $search, $limit, $offset ) {
 787                 $user = User::newFromName( $search );
 788                 if ( !$user ) {
 789                         // No prefix suggestion for invalid user
 790                         return [];
 791                 }
 792                 // Autocomplete subpage as user list - public to allow caching
 793                 return UserNamePrefixSearch::search( 'public', $search, $limit, $offset );
 794         }
 795
 796         protected function getGroupName() {
 797                 return 'users';
 798         }
 799 }