wikimedia/mediawiki-core

<?php
/**
 * Prefix search of user names.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

namespace MediaWiki\User;

use InvalidArgumentException;
use MediaWiki\Block\HideUserUtils;
use MediaWiki\Permissions\Authority;
use Wikimedia\Rdbms\IConnectionProvider;
use Wikimedia\Rdbms\IExpression;
use Wikimedia\Rdbms\LikeValue;

/**
 * Handles searching prefixes of user names
 *
 * @note There are two classes called UserNamePrefixSearch.  You should use this first one, in
 * namespace MediaWiki\User, which is a service.  \UserNamePrefixSearch is a deprecated static wrapper
 * that forwards to the global service.
 *
 * @since 1.36 as a service in the current namespace
 * @author DannyS712
 */
class UserNamePrefixSearch {

    /** @var string */
    public const AUDIENCE_PUBLIC = 'public';

    private IConnectionProvider $dbProvider;
    private UserNameUtils $userNameUtils;
    private HideUserUtils $hideUserUtils;

    /**
     * @param IConnectionProvider $dbProvider
     * @param UserNameUtils $userNameUtils
     * @param HideUserUtils $hideUserUtils
     */
    public function __construct(
        IConnectionProvider $dbProvider,
        UserNameUtils $userNameUtils,
        HideUserUtils $hideUserUtils
    ) {
        $this->dbProvider = $dbProvider;
        $this->userNameUtils = $userNameUtils;
        $this->hideUserUtils = $hideUserUtils;
    }

    /**
     * Do a prefix search of user names and return a list of matching user names.
     *
     * @param string|Authority $audience Either AUDIENCE_PUBLIC or a user to
     *    show the search for
     * @param string $search
     * @param int $limit
     * @param int $offset How many results to offset from the beginning
     * @return string[]
     * @throws InvalidArgumentException if $audience is invalid
     */
    public function search( $audience, string $search, int $limit, int $offset = 0 ): array {
        if ( $audience !== self::AUDIENCE_PUBLIC &&
            !( $audience instanceof Authority )
        ) {
            throw new InvalidArgumentException(
                '$audience must be AUDIENCE_PUBLIC or an Authority object'
            );
        }

        // Invalid user names are treated as empty strings
        $prefix = $this->userNameUtils->getCanonical( $search ) ?: '';

        $dbr = $this->dbProvider->getReplicaDatabase();
        $queryBuilder = $dbr->newSelectQueryBuilder()
            ->select( 'user_name' )
            ->from( 'user' )
            ->where( $dbr->expr( 'user_name', IExpression::LIKE, new LikeValue( $prefix, $dbr->anyString() ) ) )
            ->orderBy( 'user_name' )
            ->limit( $limit )
            ->offset( $offset );

        // Filter out hidden user names
        if ( $audience === self::AUDIENCE_PUBLIC || !$audience->isAllowed( 'hideuser' ) ) {
            $queryBuilder->andWhere( $this->hideUserUtils->getExpression( $dbr ) );
        }

        return $queryBuilder->caller( __METHOD__ )->fetchFieldValues();
    }
}