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diff --git a/www/wiki/includes/specials/SpecialRandomInCategory.php b/www/wiki/includes/specials/SpecialRandomInCategory.php
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+++ b/www/wiki/includes/specials/SpecialRandomInCategory.php
@@ -0,0 +1,315 @@
+<?php
+/**
+ * Implements Special:RandomInCategory
+ *
+ * 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
+ * @ingroup SpecialPage
+ * @author Brian Wolff
+ */
+
+/**
+ * Special page to direct the user to a random page
+ *
+ * @note The method used here is rather biased. It is assumed that
+ * the use of this page will be people wanting to get a random page
+ * out of a maintenance category, to fix it up. The method used by
+ * this page should return different pages in an unpredictable fashion
+ * which is hoped to be sufficient, even if some pages are selected
+ * more often than others.
+ *
+ * A more unbiased method could be achieved by adding a cl_random field
+ * to the categorylinks table.
+ *
+ * The method used here is as follows:
+ *  * Find the smallest and largest timestamp in the category
+ *  * Pick a random timestamp in between
+ *  * Pick an offset between 0 and 30
+ *  * Get the offset'ed page that is newer than the timestamp selected
+ * The offset is meant to counter the fact the timestamps aren't usually
+ * uniformly distributed, so if things are very non-uniform at least we
+ * won't have the same page selected 99% of the time.
+ *
+ * @ingroup SpecialPage
+ */
+class SpecialRandomInCategory extends FormSpecialPage {
+	/** @var string[] */
+	protected $extra = []; // Extra SQL statements
+	/** @var Title|false */
+	protected $category = false; // Title object of category
+	/** @var int */
+	protected $maxOffset = 30; // Max amount to fudge randomness by.
+	/** @var int|null */
+	private $maxTimestamp = null;
+	/** @var int|null */
+	private $minTimestamp = null;
+
+	public function __construct( $name = 'RandomInCategory' ) {
+		parent::__construct( $name );
+	}
+
+	/**
+	 * Set which category to use.
+	 * @param Title $cat
+	 */
+	public function setCategory( Title $cat ) {
+		$this->category = $cat;
+		$this->maxTimestamp = null;
+		$this->minTimestamp = null;
+	}
+
+	protected function getFormFields() {
+		$this->addHelpLink( 'Help:RandomInCategory' );
+
+		return [
+			'category' => [
+				'type' => 'title',
+				'namespace' => NS_CATEGORY,
+				'relative' => true,
+				'label-message' => 'randomincategory-category',
+				'required' => true,
+			]
+		];
+	}
+
+	public function requiresWrite() {
+		return false;
+	}
+
+	public function requiresUnblock() {
+		return false;
+	}
+
+	protected function getDisplayFormat() {
+		return 'ooui';
+	}
+
+	protected function alterForm( HTMLForm $form ) {
+		$form->setSubmitTextMsg( 'randomincategory-submit' );
+	}
+
+	protected function setParameter( $par ) {
+		// if subpage present, fake form submission
+		$this->onSubmit( [ 'category' => $par ] );
+	}
+
+	public function onSubmit( array $data ) {
+		$cat = false;
+
+		$categoryStr = $data['category'];
+
+		if ( $categoryStr ) {
+			$cat = Title::newFromText( $categoryStr, NS_CATEGORY );
+		}
+
+		if ( $cat && $cat->getNamespace() !== NS_CATEGORY ) {
+			// Someone searching for something like "Wikipedia:Foo"
+			$cat = Title::makeTitleSafe( NS_CATEGORY, $categoryStr );
+		}
+
+		if ( $cat ) {
+			$this->setCategory( $cat );
+		}
+
+		if ( !$this->category && $categoryStr ) {
+			$msg = $this->msg( 'randomincategory-invalidcategory',
+				wfEscapeWikiText( $categoryStr ) );
+
+			return Status::newFatal( $msg );
+
+		} elseif ( !$this->category ) {
+			return false; // no data sent
+		}
+
+		$title = $this->getRandomTitle();
+
+		if ( is_null( $title ) ) {
+			$msg = $this->msg( 'randomincategory-nopages',
+				$this->category->getText() );
+
+			return Status::newFatal( $msg );
+		}
+
+		$this->getOutput()->redirect( $title->getFullURL() );
+	}
+
+	/**
+	 * Choose a random title.
+	 * @return Title|null Title object (or null if nothing to choose from)
+	 */
+	public function getRandomTitle() {
+		// Convert to float, since we do math with the random number.
+		$rand = (float)wfRandom();
+		$title = null;
+
+		// Given that timestamps are rather unevenly distributed, we also
+		// use an offset between 0 and 30 to make any biases less noticeable.
+		$offset = mt_rand( 0, $this->maxOffset );
+
+		if ( mt_rand( 0, 1 ) ) {
+			$up = true;
+		} else {
+			$up = false;
+		}
+
+		$row = $this->selectRandomPageFromDB( $rand, $offset, $up );
+
+		// Try again without the timestamp offset (wrap around the end)
+		if ( !$row ) {
+			$row = $this->selectRandomPageFromDB( false, $offset, $up );
+		}
+
+		// Maybe the category is really small and offset too high
+		if ( !$row ) {
+			$row = $this->selectRandomPageFromDB( $rand, 0, $up );
+		}
+
+		// Just get the first entry.
+		if ( !$row ) {
+			$row = $this->selectRandomPageFromDB( false, 0, true );
+		}
+
+		if ( $row ) {
+			return Title::makeTitle( $row->page_namespace, $row->page_title );
+		}
+
+		return null;
+	}
+
+	/**
+	 * @param float $rand Random number between 0 and 1
+	 * @param int $offset Extra offset to fudge randomness
+	 * @param bool $up True to get the result above the random number, false for below
+	 * @return array Query information.
+	 * @throws MWException
+	 * @note The $up parameter is supposed to counteract what would happen if there
+	 *   was a large gap in the distribution of cl_timestamp values. This way instead
+	 *   of things to the right of the gap being favoured, both sides of the gap
+	 *   are favoured.
+	 */
+	protected function getQueryInfo( $rand, $offset, $up ) {
+		$op = $up ? '>=' : '<=';
+		$dir = $up ? 'ASC' : 'DESC';
+		if ( !$this->category instanceof Title ) {
+			throw new MWException( 'No category set' );
+		}
+		$qi = [
+			'tables' => [ 'categorylinks', 'page' ],
+			'fields' => [ 'page_title', 'page_namespace' ],
+			'conds' => array_merge( [
+				'cl_to' => $this->category->getDBkey(),
+			], $this->extra ),
+			'options' => [
+				'ORDER BY' => 'cl_timestamp ' . $dir,
+				'LIMIT' => 1,
+				'OFFSET' => $offset
+			],
+			'join_conds' => [
+				'page' => [ 'INNER JOIN', 'cl_from = page_id' ]
+			]
+		];
+
+		$dbr = wfGetDB( DB_REPLICA );
+		$minClTime = $this->getTimestampOffset( $rand );
+		if ( $minClTime ) {
+			$qi['conds'][] = 'cl_timestamp ' . $op . ' ' .
+				$dbr->addQuotes( $dbr->timestamp( $minClTime ) );
+		}
+
+		return $qi;
+	}
+
+	/**
+	 * @param float $rand Random number between 0 and 1
+	 *
+	 * @return int|bool A random (unix) timestamp from the range of the category or false on failure
+	 */
+	protected function getTimestampOffset( $rand ) {
+		if ( $rand === false ) {
+			return false;
+		}
+		if ( !$this->minTimestamp || !$this->maxTimestamp ) {
+			try {
+				list( $this->minTimestamp, $this->maxTimestamp ) = $this->getMinAndMaxForCat( $this->category );
+			} catch ( Exception $e ) {
+				// Possibly no entries in category.
+				return false;
+			}
+		}
+
+		$ts = ( $this->maxTimestamp - $this->minTimestamp ) * $rand + $this->minTimestamp;
+
+		return intval( $ts );
+	}
+
+	/**
+	 * Get the lowest and highest timestamp for a category.
+	 *
+	 * @param Title $category
+	 * @return array The lowest and highest timestamp
+	 * @throws MWException If category has no entries.
+	 */
+	protected function getMinAndMaxForCat( Title $category ) {
+		$dbr = wfGetDB( DB_REPLICA );
+		$res = $dbr->selectRow(
+			'categorylinks',
+			[
+				'low' => 'MIN( cl_timestamp )',
+				'high' => 'MAX( cl_timestamp )'
+			],
+			[
+				'cl_to' => $this->category->getDBkey(),
+			],
+			__METHOD__,
+			[
+				'LIMIT' => 1
+			]
+		);
+		if ( !$res ) {
+			throw new MWException( 'No entries in category' );
+		}
+
+		return [ wfTimestamp( TS_UNIX, $res->low ), wfTimestamp( TS_UNIX, $res->high ) ];
+	}
+
+	/**
+	 * @param float $rand A random number that is converted to a random timestamp
+	 * @param int $offset A small offset to make the result seem more "random"
+	 * @param bool $up Get the result above the random value
+	 * @param string $fname The name of the calling method
+	 * @return array Info for the title selected.
+	 */
+	private function selectRandomPageFromDB( $rand, $offset, $up, $fname = __METHOD__ ) {
+		$dbr = wfGetDB( DB_REPLICA );
+
+		$query = $this->getQueryInfo( $rand, $offset, $up );
+		$res = $dbr->select(
+			$query['tables'],
+			$query['fields'],
+			$query['conds'],
+			$fname,
+			$query['options'],
+			$query['join_conds']
+		);
+
+		return $res->fetchObject();
+	}
+
+	protected function getGroupName() {
+		return 'redirects';
+	}
+}