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         /**
  31          * The target of the local right-adjuster's interest.  Can be gotten from
  32          * either a GET parameter or a subpage-style parameter, so have a member
  33          * variable for it.
  34          * @var null|string $mTarget
  35          */
  36         protected $mTarget;
  37         /*
  38          * @var null|User $mFetchedUser The user object of the target username or null.
  39          */
  40         protected $mFetchedUser = null;
  41         protected $isself = false;
  42
  43         public function __construct() {
  44                 parent::__construct( 'Userrights' );
  45         }
  46
  47         public function doesWrites() {
  48                 return true;
  49         }
  50
  51         /**
  52          * Check whether the current user (from context) can change the target user's rights.
  53          *
  54          * @param User $targetUser User whose rights are being changed
  55          * @param bool $checkIfSelf If false, assume that the current user can add/remove groups defined
  56          *   in $wgGroupsAddToSelf / $wgGroupsRemoveFromSelf, without checking if it's the same as target
  57          *   user
  58          * @return bool
  59          */
  60         public function userCanChangeRights( $targetUser, $checkIfSelf = true ) {
  61                 $isself = $this->getUser()->equals( $targetUser );
  62
  63                 $available = $this->changeableGroups();
  64                 if ( $targetUser->getId() == 0 ) {
  65                         return false;
  66                 }
  67
  68                 return !empty( $available['add'] )
  69                         || !empty( $available['remove'] )
  70                         || ( ( $isself || !$checkIfSelf ) &&
  71                                 ( !empty( $available['add-self'] )
  72                                         || !empty( $available['remove-self'] ) ) );
  73         }
  74
  75         /**
  76          * Manage forms to be shown according to posted data.
  77          * Depending on the submit button used, call a form or a save function.
  78          *
  79          * @param string|null $par String if any subpage provided, else null
  80          * @throws UserBlockedError|PermissionsError
  81          */
  82         public function execute( $par ) {
  83                 $user = $this->getUser();
  84                 $request = $this->getRequest();
  85                 $session = $request->getSession();
  86                 $out = $this->getOutput();
  87
  88                 if ( $par !== null ) {
  89                         $this->mTarget = $par;
  90                 } else {
  91                         $this->mTarget = $request->getVal( 'user' );
  92                 }
  93
  94                 if ( is_string( $this->mTarget ) ) {
  95                         $this->mTarget = trim( $this->mTarget );
  96                 }
  97
  98                 if ( $this->mTarget !== null && User::getCanonicalName( $this->mTarget ) === $user->getName() ) {
  99                         $this->isself = true;
 100                 }
 101
 102                 $fetchedStatus = $this->fetchUser( $this->mTarget, true );
 103                 if ( $fetchedStatus->isOK() ) {
 104                         $this->mFetchedUser = $fetchedStatus->value;
 105                         if ( $this->mFetchedUser instanceof User ) {
 106                                 // Set the 'relevant user' in the skin, so it displays links like Contributions,
 107                                 // User logs, UserRights, etc.
 108                                 $this->getSkin()->setRelevantUser( $this->mFetchedUser );
 109                         }
 110                 }
 111
 112                 // show a successbox, if the user rights was saved successfully
 113                 if (
 114                         $session->get( 'specialUserrightsSaveSuccess' ) &&
 115                         $this->mFetchedUser !== null
 116                 ) {
 117                         // Remove session data for the success message
 118                         $session->remove( 'specialUserrightsSaveSuccess' );
 119
 120                         $out->addModules( [ 'mediawiki.special.userrights' ] );
 121                         $out->addModuleStyles( 'mediawiki.notification.convertmessagebox.styles' );
 122                         $out->addHTML(
 123                                 Html::rawElement(
 124                                         'div',
 125                                         [
 126                                                 'class' => 'mw-notify-success successbox',
 127                                                 'id' => 'mw-preferences-success',
 128                                                 'data-mw-autohide' => 'false',
 129                                         ],
 130                                         Html::element(
 131                                                 'p',
 132                                                 [],
 133                                                 $this->msg( 'savedrights', $this->mFetchedUser->getName() )->text()
 134                                         )
 135                                 )
 136                         );
 137                 }
 138
 139                 $this->setHeaders();
 140                 $this->outputHeader();
 141
 142                 $out->addModuleStyles( 'mediawiki.special' );
 143                 $this->addHelpLink( 'Help:Assigning permissions' );
 144
 145                 $this->switchForm();
 146
 147                 if (
 148                         $request->wasPosted() &&
 149                         $request->getCheck( 'saveusergroups' ) &&
 150                         $this->mTarget !== null &&
 151                         $user->matchEditToken( $request->getVal( 'wpEditToken' ), $this->mTarget )
 152                 ) {
 153                         /*
 154                         * If the user is blocked and they only have "partial" access
 155                         * (e.g. they don't have the userrights permission), then don't
 156                         * allow them to change any user rights.
 157                         */
 158                         if ( $user->isBlocked() && !$user->isAllowed( 'userrights' ) ) {
 159                                 throw new UserBlockedError( $user->getBlock() );
 160                         }
 161
 162                         $this->checkReadOnly();
 163
 164                         // save settings
 165                         if ( !$fetchedStatus->isOK() ) {
 166                                 $this->getOutput()->addWikiText( $fetchedStatus->getWikiText() );
 167
 168                                 return;
 169                         }
 170
 171                         $targetUser = $this->mFetchedUser;
 172                         if ( $targetUser instanceof User ) { // UserRightsProxy doesn't have this method (bug 61252)
 173                                 $targetUser->clearInstanceCache(); // bug 38989
 174                         }
 175
 176                         if ( $request->getVal( 'conflictcheck-originalgroups' )
 177                                 !== implode( ',', $targetUser->getGroups() )
 178                         ) {
 179                                 $out->addWikiMsg( 'userrights-conflict' );
 180                         } else {
 181                                 $this->saveUserGroups(
 182                                         $this->mTarget,
 183                                         $request->getVal( 'user-reason' ),
 184                                         $targetUser
 185                                 );
 186
 187                                 // Set session data for the success message
 188                                 $session->set( 'specialUserrightsSaveSuccess', 1 );
 189
 190                                 $out->redirect( $this->getSuccessURL() );
 191
 192                                 return;
 193                         }
 194                 }
 195
 196                 // show some more forms
 197                 if ( $this->mTarget !== null ) {
 198                         $this->editUserGroupsForm( $this->mTarget );
 199                 }
 200         }
 201
 202         function getSuccessURL() {
 203                 return $this->getPageTitle( $this->mTarget )->getFullURL();
 204         }
 205
 206         /**
 207          * Save user groups changes in the database.
 208          * Data comes from the editUserGroupsForm() form function
 209          *
 210          * @param string $username Username to apply changes to.
 211          * @param string $reason Reason for group change
 212          * @param User|UserRightsProxy $user Target user object.
 213          * @return null
 214          */
 215         function saveUserGroups( $username, $reason, $user ) {
 216                 $allgroups = $this->getAllGroups();
 217                 $addgroup = [];
 218                 $removegroup = [];
 219
 220                 // This could possibly create a highly unlikely race condition if permissions are changed between
 221                 //  when the form is loaded and when the form is saved. Ignoring it for the moment.
 222                 foreach ( $allgroups as $group ) {
 223                         // We'll tell it to remove all unchecked groups, and add all checked groups.
 224                         // Later on, this gets filtered for what can actually be removed
 225                         if ( $this->getRequest()->getCheck( "wpGroup-$group" ) ) {
 226                                 $addgroup[] = $group;
 227                         } else {
 228                                 $removegroup[] = $group;
 229                         }
 230                 }
 231
 232                 $this->doSaveUserGroups( $user, $addgroup, $removegroup, $reason );
 233         }
 234
 235         /**
 236          * Save user groups changes in the database.
 237          *
 238          * @param User|UserRightsProxy $user
 239          * @param array $add Array of groups to add
 240          * @param array $remove Array of groups to remove
 241          * @param string $reason Reason for group change
 242          * @param array $tags Array of change tags to add to the log entry
 243          * @return array Tuple of added, then removed groups
 244          */
 245         function doSaveUserGroups( $user, $add, $remove, $reason = '', $tags = [] ) {
 246                 // Validate input set...
 247                 $isself = $user->getName() == $this->getUser()->getName();
 248                 $groups = $user->getGroups();
 249                 $changeable = $this->changeableGroups();
 250                 $addable = array_merge( $changeable['add'], $isself ? $changeable['add-self'] : [] );
 251                 $removable = array_merge( $changeable['remove'], $isself ? $changeable['remove-self'] : [] );
 252
 253                 $remove = array_unique(
 254                         array_intersect( (array)$remove, $removable, $groups ) );
 255                 $add = array_unique( array_diff(
 256                         array_intersect( (array)$add, $addable ),
 257                         $groups )
 258                 );
 259
 260                 Hooks::run( 'ChangeUserGroups', [ $this->getUser(), $user, &$add, &$remove ] );
 261
 262                 $oldGroups = $user->getGroups();
 263                 $newGroups = $oldGroups;
 264
 265                 // Remove then add groups
 266                 if ( $remove ) {
 267                         foreach ( $remove as $index => $group ) {
 268                                 if ( !$user->removeGroup( $group ) ) {
 269                                         unset( $remove[$index] );
 270                                 }
 271                         }
 272                         $newGroups = array_diff( $newGroups, $remove );
 273                 }
 274                 if ( $add ) {
 275                         foreach ( $add as $index => $group ) {
 276                                 if ( !$user->addGroup( $group ) ) {
 277                                         unset( $add[$index] );
 278                                 }
 279                         }
 280                         $newGroups = array_merge( $newGroups, $add );
 281                 }
 282                 $newGroups = array_unique( $newGroups );
 283
 284                 // Ensure that caches are cleared
 285                 $user->invalidateCache();
 286
 287                 // update groups in external authentication database
 288                 Hooks::run( 'UserGroupsChanged', [ $user, $add, $remove, $this->getUser(), $reason ] );
 289                 MediaWiki\Auth\AuthManager::callLegacyAuthPlugin(
 290                         'updateExternalDBGroups', [ $user, $add, $remove ]
 291                 );
 292
 293                 wfDebug( 'oldGroups: ' . print_r( $oldGroups, true ) . "\n" );
 294                 wfDebug( 'newGroups: ' . print_r( $newGroups, true ) . "\n" );
 295                 // Deprecated in favor of UserGroupsChanged hook
 296                 Hooks::run( 'UserRights', [ &$user, $add, $remove ], '1.26' );
 297
 298                 if ( $newGroups != $oldGroups ) {
 299                         $this->addLogEntry( $user, $oldGroups, $newGroups, $reason, $tags );
 300                 }
 301
 302                 return [ $add, $remove ];
 303         }
 304
 305         /**
 306          * Add a rights log entry for an action.
 307          * @param User $user
 308          * @param array $oldGroups
 309          * @param array $newGroups
 310          * @param array $reason
 311          * @param array $tags
 312          */
 313         function addLogEntry( $user, $oldGroups, $newGroups, $reason, $tags ) {
 314                 $logEntry = new ManualLogEntry( 'rights', 'rights' );
 315                 $logEntry->setPerformer( $this->getUser() );
 316                 $logEntry->setTarget( $user->getUserPage() );
 317                 $logEntry->setComment( $reason );
 318                 $logEntry->setParameters( [
 319                         '4::oldgroups' => $oldGroups,
 320                         '5::newgroups' => $newGroups,
 321                 ] );
 322                 $logid = $logEntry->insert();
 323                 if ( count( $tags ) ) {
 324                         $logEntry->setTags( $tags );
 325                 }
 326                 $logEntry->publish( $logid );
 327         }
 328
 329         /**
 330          * Edit user groups membership
 331          * @param string $username Name of the user.
 332          */
 333         function editUserGroupsForm( $username ) {
 334                 $status = $this->fetchUser( $username, true );
 335                 if ( !$status->isOK() ) {
 336                         $this->getOutput()->addWikiText( $status->getWikiText() );
 337
 338                         return;
 339                 } else {
 340                         $user = $status->value;
 341                 }
 342
 343                 $groups = $user->getGroups();
 344
 345                 $this->showEditUserGroupsForm( $user, $groups );
 346
 347                 // This isn't really ideal logging behavior, but let's not hide the
 348                 // interwiki logs if we're using them as is.
 349                 $this->showLogFragment( $user, $this->getOutput() );
 350         }
 351
 352         /**
 353          * Normalize the input username, which may be local or remote, and
 354          * return a user (or proxy) object for manipulating it.
 355          *
 356          * Side effects: error output for invalid access
 357          * @param string $username
 358          * @param bool $writing
 359          * @return Status
 360          */
 361         public function fetchUser( $username, $writing = true ) {
 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 ( $writing && !$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( 'editusergroup' )->text()
 468                         ) .
 469                         Html::closeElement( 'fieldset' ) .
 470                         Html::closeElement( 'form' ) . "\n"
 471                 );
 472         }
 473
 474         /**
 475          * Show the form to edit group memberships.
 476          *
 477          * @param User|UserRightsProxy $user User or UserRightsProxy you're editing
 478          * @param array $groups Array of groups the user is in
 479          */
 480         protected function showEditUserGroupsForm( $user, $groups ) {
 481                 $list = [];
 482                 $membersList = [];
 483                 foreach ( $groups as $group ) {
 484                         $list[] = self::buildGroupLink( $group );
 485                         $membersList[] = self::buildGroupMemberLink( $group );
 486                 }
 487
 488                 $autoList = [];
 489                 $autoMembersList = [];
 490                 if ( $user instanceof User ) {
 491                         foreach ( Autopromote::getAutopromoteGroups( $user ) as $group ) {
 492                                 $autoList[] = self::buildGroupLink( $group );
 493                                 $autoMembersList[] = self::buildGroupMemberLink( $group );
 494                         }
 495                 }
 496
 497                 $language = $this->getLanguage();
 498                 $displayedList = $this->msg( 'userrights-groupsmember-type' )
 499                         ->rawParams(
 500                                 $language->listToText( $list ),
 501                                 $language->listToText( $membersList )
 502                         )->escaped();
 503                 $displayedAutolist = $this->msg( 'userrights-groupsmember-type' )
 504                         ->rawParams(
 505                                 $language->listToText( $autoList ),
 506                                 $language->listToText( $autoMembersList )
 507                         )->escaped();
 508
 509                 $grouplist = '';
 510                 $count = count( $list );
 511                 if ( $count > 0 ) {
 512                         $grouplist = $this->msg( 'userrights-groupsmember' )
 513                                 ->numParams( $count )
 514                                 ->params( $user->getName() )
 515                                 ->parse();
 516                         $grouplist = '<p>' . $grouplist . ' ' . $displayedList . "</p>\n";
 517                 }
 518
 519                 $count = count( $autoList );
 520                 if ( $count > 0 ) {
 521                         $autogrouplistintro = $this->msg( 'userrights-groupsmember-auto' )
 522                                 ->numParams( $count )
 523                                 ->params( $user->getName() )
 524                                 ->parse();
 525                         $grouplist .= '<p>' . $autogrouplistintro . ' ' . $displayedAutolist . "</p>\n";
 526                 }
 527
 528                 $userToolLinks = Linker::userToolLinks(
 529                         $user->getId(),
 530                         $user->getName(),
 531                         false, /* default for redContribsWhenNoEdits */
 532                         Linker::TOOL_LINKS_EMAIL /* Add "send e-mail" link */
 533                 );
 534
 535                 list( $groupCheckboxes, $canChangeAny ) = $this->groupCheckboxes( $groups, $user );
 536                 $this->getOutput()->addHTML(
 537                         Xml::openElement(
 538                                 'form',
 539                                 [
 540                                         'method' => 'post',
 541                                         'action' => $this->getPageTitle()->getLocalURL(),
 542                                         'name' => 'editGroup',
 543                                         'id' => 'mw-userrights-form2'
 544                                 ]
 545                         ) .
 546                         Html::hidden( 'user', $this->mTarget ) .
 547                         Html::hidden( 'wpEditToken', $this->getUser()->getEditToken( $this->mTarget ) ) .
 548                         Html::hidden(
 549                                 'conflictcheck-originalgroups',
 550                                 implode( ',', $user->getGroups() )
 551                         ) . // Conflict detection
 552                         Xml::openElement( 'fieldset' ) .
 553                         Xml::element(
 554                                 'legend',
 555                                 [],
 556                                 $this->msg(
 557                                         $canChangeAny ? 'userrights-editusergroup' : 'userrights-viewusergroup',
 558                                         $user->getName()
 559                                 )->text()
 560                         ) .
 561                         $this->msg(
 562                                 $canChangeAny ? 'editinguser' : 'viewinguserrights'
 563                         )->params( wfEscapeWikiText( $user->getName() ) )
 564                                 ->rawParams( $userToolLinks )->parse()
 565                 );
 566                 if ( $canChangeAny ) {
 567                         $this->getOutput()->addHTML(
 568                                 $this->msg( 'userrights-groups-help', $user->getName() )->parse() .
 569                                 $grouplist .
 570                                 $groupCheckboxes .
 571                                 Xml::openElement( 'table', [ 'id' => 'mw-userrights-table-outer' ] ) .
 572                                         "<tr>
 573                                                 <td class='mw-label'>" .
 574                                                         Xml::label( $this->msg( 'userrights-reason' )->text(), 'wpReason' ) .
 575                                                 "</td>
 576                                                 <td class='mw-input'>" .
 577                                                         Xml::input( 'user-reason', 60, $this->getRequest()->getVal( 'user-reason', false ),
 578                                                                 [ 'id' => 'wpReason', 'maxlength' => 255 ] ) .
 579                                                 "</td>
 580                                         </tr>
 581                                         <tr>
 582                                                 <td></td>
 583                                                 <td class='mw-submit'>" .
 584                                                         Xml::submitButton( $this->msg( 'saveusergroups', $user->getName() )->text(),
 585                                                                 [ 'name' => 'saveusergroups' ] +
 586                                                                         Linker::tooltipAndAccesskeyAttribs( 'userrights-set' )
 587                                                         ) .
 588                                                 "</td>
 589                                         </tr>" .
 590                                 Xml::closeElement( 'table' ) . "\n"
 591                         );
 592                 } else {
 593                         $this->getOutput()->addHTML( $grouplist );
 594                 }
 595                 $this->getOutput()->addHTML(
 596                         Xml::closeElement( 'fieldset' ) .
 597                         Xml::closeElement( 'form' ) . "\n"
 598                 );
 599         }
 600
 601         /**
 602          * Format a link to a group description page
 603          *
 604          * @param string $group
 605          * @return string
 606          */
 607         private static function buildGroupLink( $group ) {
 608                 return User::makeGroupLinkHTML( $group, User::getGroupName( $group ) );
 609         }
 610
 611         /**
 612          * Format a link to a group member description page
 613          *
 614          * @param string $group
 615          * @return string
 616          */
 617         private static function buildGroupMemberLink( $group ) {
 618                 return User::makeGroupLinkHTML( $group, User::getGroupMember( $group ) );
 619         }
 620
 621         /**
 622          * Returns an array of all groups that may be edited
 623          * @return array Array of groups that may be edited.
 624          */
 625         protected static function getAllGroups() {
 626                 return User::getAllGroups();
 627         }
 628
 629         /**
 630          * Adds a table with checkboxes where you can select what groups to add/remove
 631          *
 632          * @todo Just pass the username string?
 633          * @param array $usergroups Groups the user belongs to
 634          * @param User $user
 635          * @return Array with 2 elements: the XHTML table element with checkxboes, and
 636          * whether any groups are changeable
 637          */
 638         private function groupCheckboxes( $usergroups, $user ) {
 639                 $allgroups = $this->getAllGroups();
 640                 $ret = '';
 641
 642                 // Put all column info into an associative array so that extensions can
 643                 // more easily manage it.
 644                 $columns = [ 'unchangeable' => [], 'changeable' => [] ];
 645
 646                 foreach ( $allgroups as $group ) {
 647                         $set = in_array( $group, $usergroups );
 648                         // Should the checkbox be disabled?
 649                         $disabled = !(
 650                                 ( $set && $this->canRemove( $group ) ) ||
 651                                 ( !$set && $this->canAdd( $group ) ) );
 652                         // Do we need to point out that this action is irreversible?
 653                         $irreversible = !$disabled && (
 654                                 ( $set && !$this->canAdd( $group ) ) ||
 655                                 ( !$set && !$this->canRemove( $group ) ) );
 656
 657                         $checkbox = [
 658                                 'set' => $set,
 659                                 'disabled' => $disabled,
 660                                 'irreversible' => $irreversible
 661                         ];
 662
 663                         if ( $disabled ) {
 664                                 $columns['unchangeable'][$group] = $checkbox;
 665                         } else {
 666                                 $columns['changeable'][$group] = $checkbox;
 667                         }
 668                 }
 669
 670                 // Build the HTML table
 671                 $ret .= Xml::openElement( 'table', [ 'class' => 'mw-userrights-groups' ] ) .
 672                         "<tr>\n";
 673                 foreach ( $columns as $name => $column ) {
 674                         if ( $column === [] ) {
 675                                 continue;
 676                         }
 677                         // Messages: userrights-changeable-col, userrights-unchangeable-col
 678                         $ret .= Xml::element(
 679                                 'th',
 680                                 null,
 681                                 $this->msg( 'userrights-' . $name . '-col', count( $column ) )->text()
 682                         );
 683                 }
 684
 685                 $ret .= "</tr>\n<tr>\n";
 686                 foreach ( $columns as $column ) {
 687                         if ( $column === [] ) {
 688                                 continue;
 689                         }
 690                         $ret .= "\t<td style='vertical-align:top;'>\n";
 691                         foreach ( $column as $group => $checkbox ) {
 692                                 $attr = $checkbox['disabled'] ? [ 'disabled' => 'disabled' ] : [];
 693
 694                                 $member = User::getGroupMember( $group, $user->getName() );
 695                                 if ( $checkbox['irreversible'] ) {
 696                                         $text = $this->msg( 'userrights-irreversible-marker', $member )->text();
 697                                 } else {
 698                                         $text = $member;
 699                                 }
 700                                 $checkboxHtml = Xml::checkLabel( $text, "wpGroup-" . $group,
 701                                         "wpGroup-" . $group, $checkbox['set'], $attr );
 702                                 $ret .= "\t\t" . ( $checkbox['disabled']
 703                                         ? Xml::tags( 'span', [ 'class' => 'mw-userrights-disabled' ], $checkboxHtml )
 704                                         : $checkboxHtml
 705                                 ) . "<br />\n";
 706                         }
 707                         $ret .= "\t</td>\n";
 708                 }
 709                 $ret .= Xml::closeElement( 'tr' ) . Xml::closeElement( 'table' );
 710
 711                 return [ $ret, (bool)$columns['changeable'] ];
 712         }
 713
 714         /**
 715          * @param string $group The name of the group to check
 716          * @return bool Can we remove the group?
 717          */
 718         private function canRemove( $group ) {
 719                 $groups = $this->changeableGroups();
 720
 721                 return in_array(
 722                         $group,
 723                         $groups['remove'] ) || ( $this->isself && in_array( $group, $groups['remove-self'] )
 724                 );
 725         }
 726
 727         /**
 728          * @param string $group The name of the group to check
 729          * @return bool Can we add the group?
 730          */
 731         private function canAdd( $group ) {
 732                 $groups = $this->changeableGroups();
 733
 734                 return in_array(
 735                         $group,
 736                         $groups['add'] ) || ( $this->isself && in_array( $group, $groups['add-self'] )
 737                 );
 738         }
 739
 740         /**
 741          * Returns $this->getUser()->changeableGroups()
 742          *
 743          * @return array Array(
 744          *   'add' => array( addablegroups ),
 745          *   'remove' => array( removablegroups ),
 746          *   'add-self' => array( addablegroups to self ),
 747          *   'remove-self' => array( removable groups from self )
 748          *  )
 749          */
 750         function changeableGroups() {
 751                 return $this->getUser()->changeableGroups();
 752         }
 753
 754         /**
 755          * Show a rights log fragment for the specified user
 756          *
 757          * @param User $user User to show log for
 758          * @param OutputPage $output OutputPage to use
 759          */
 760         protected function showLogFragment( $user, $output ) {
 761                 $rightsLogPage = new LogPage( 'rights' );
 762                 $output->addHTML( Xml::element( 'h2', null, $rightsLogPage->getName()->text() ) );
 763                 LogEventsList::showLogExtract( $output, 'rights', $user->getUserPage() );
 764         }
 765
 766         /**
 767          * Return an array of subpages beginning with $search that this special page will accept.
 768          *
 769          * @param string $search Prefix to search for
 770          * @param int $limit Maximum number of results to return (usually 10)
 771          * @param int $offset Number of results to skip (usually 0)
 772          * @return string[] Matching subpages
 773          */
 774         public function prefixSearchSubpages( $search, $limit, $offset ) {
 775                 $user = User::newFromName( $search );
 776                 if ( !$user ) {
 777                         // No prefix suggestion for invalid user
 778                         return [];
 779                 }
 780                 // Autocomplete subpage as user list - public to allow caching
 781                 return UserNamePrefixSearch::search( 'public', $search, $limit, $offset );
 782         }
 783
 784         protected function getGroupName() {
 785                 return 'users';
 786         }
 787 }