<?php

/*
 * Created on July 7, 2007
 *
 * API for MediaWiki 1.8+
 *
 * Copyright (C) 2007 Yuri Astrakhan <Firstname><Lastname>@gmail.com
 *
 * 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.,
 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 * http://www.gnu.org/copyleft/gpl.html
 */

if ( !defined( 'MEDIAWIKI' ) ) {
	// Eclipse helper - will be ignored in production
	require_once ( 'ApiQueryBase.php' );
}

/**
 * Query module to enumerate all registered users.
 *
 * @ingroup API
 */
class ApiQueryAllUsers extends ApiQueryBase {

	public function __construct( $query, $moduleName ) {
		parent :: __construct( $query, $moduleName, 'au' );
	}

	public function execute() {
		$db = $this->getDB();
		$params = $this->extractRequestParams();

		$prop = $params['prop'];
		if ( !is_null( $prop ) ) {
			$prop = array_flip( $prop );
			$fld_blockinfo = isset( $prop['blockinfo'] );
			$fld_editcount = isset( $prop['editcount'] );
			$fld_groups = isset( $prop['groups'] );
			$fld_registration = isset( $prop['registration'] );
		} else {
			$fld_blockinfo = $fld_editcount = $fld_groups = $fld_registration = false;
		}

		$limit = $params['limit'];
		$this->addTables( 'user', 'u1' );
		$useIndex = true;

		if ( !is_null( $params['from'] ) )
			$this->addWhere( 'u1.user_name >= ' . $db->addQuotes( $this->keyToTitle( $params['from'] ) ) );

		if ( !is_null( $params['prefix'] ) )
			$this->addWhere( 'u1.user_name' . $db->buildLike( $this->keyToTitle( $params['prefix'] ), $db->anyString() ) );

		if ( !is_null( $params['group'] ) ) {
			$useIndex = false;
			// Filter only users that belong to a given group
			$this->addTables( 'user_groups', 'ug1' );
			$ug1 = $this->getAliasedName( 'user_groups', 'ug1' );
			$this->addJoinConds( array( $ug1 => array( 'INNER JOIN', array( 'ug1.ug_user=u1.user_id',
					'ug1.ug_group' => $params['group'] ) ) ) );
		}

		if ( $params['witheditsonly'] )
			$this->addWhere( 'u1.user_editcount > 0' );

		if ( $fld_groups ) {
			// Show the groups the given users belong to
			// request more than needed to avoid not getting all rows that belong to one user
			$groupCount = count( User::getAllGroups() );
			$sqlLimit = $limit + $groupCount + 1;

			$this->addTables( 'user_groups', 'ug2' );
			$tname = $this->getAliasedName( 'user_groups', 'ug2' );
			$this->addJoinConds( array( $tname => array( 'LEFT JOIN', 'ug2.ug_user=u1.user_id' ) ) );
			$this->addFields( 'ug2.ug_group ug_group2' );
		} else {
			$sqlLimit = $limit + 1;
		}
		if ( $fld_blockinfo ) {
			$this->addTables( 'ipblocks' );
			$this->addTables( 'user', 'u2' );
			$u2 = $this->getAliasedName( 'user', 'u2' );
			$this->addJoinConds( array(
				'ipblocks' => array( 'LEFT JOIN', 'ipb_user=u1.user_id' ),
				$u2 => array( 'LEFT JOIN', 'ipb_by=u2.user_id' ) ) );
			$this->addFields( array( 'ipb_reason', 'u2.user_name AS blocker_name' ) );
		}

		$this->addOption( 'LIMIT', $sqlLimit );

		$this->addFields( 'u1.user_name' );
		$this->addFieldsIf( 'u1.user_editcount', $fld_editcount );
		$this->addFieldsIf( 'u1.user_registration', $fld_registration );

		$this->addOption( 'ORDER BY', 'u1.user_name' );
		if ( $useIndex ) {
			$u1 = $this->getAliasedName( 'user', 'u1' );
			$this->addOption( 'USE INDEX', array( $u1 => 'user_name' ) );
		}

		$res = $this->select( __METHOD__ );

		$data = array ();
		$count = 0;
		$lastUserData = false;
		$lastUser = false;
		$result = $this->getResult();

		//
		// This loop keeps track of the last entry.
		// For each new row, if the new row is for different user then the last, the last entry is added to results.
		// Otherwise, the group of the new row is appended to the last entry.
		// The setContinue... is more complex because of this, and takes into account the higher sql limit
		// to make sure all rows that belong to the same user are received.
		//
		while ( true ) {

			$row = $db->fetchObject( $res );
			$count++;

			if ( !$row || $lastUser !== $row->user_name ) {
				// Save the last pass's user data
				if ( is_array( $lastUserData ) )
				{
					$fit = $result->addValue( array( 'query', $this->getModuleName() ),
							null, $lastUserData );
					if ( !$fit )
					{
						$this->setContinueEnumParameter( 'from',
								$this->keyToTitle( $lastUserData['name'] ) );
						break;
					}
				}

				// No more rows left
				if ( !$row )
					break;

				if ( $count > $limit ) {
					// We've reached the one extra which shows that there are additional pages to be had. Stop here...
					$this->setContinueEnumParameter( 'from', $this->keyToTitle( $row->user_name ) );
					break;
				}

				// Record new user's data
				$lastUser = $row->user_name;
				$lastUserData = array( 'name' => $lastUser );
				if ( $fld_blockinfo ) {
					$lastUserData['blockedby'] = $row->blocker_name;
					$lastUserData['blockreason'] = $row->ipb_reason;
				}
				if ( $fld_editcount )
					$lastUserData['editcount'] = intval( $row->user_editcount );
				if ( $fld_registration )
					$lastUserData['registration'] = $row->user_registration ?
						wfTimestamp( TS_ISO_8601, $row->user_registration ) : '';

			}

			if ( $sqlLimit == $count ) {
				// BUG!  database contains group name that User::getAllGroups() does not return
				// TODO: should handle this more gracefully
				ApiBase :: dieDebug( __METHOD__,
					'MediaWiki configuration error: the database contains more user groups than known to User::getAllGroups() function' );
			}

			// Add user's group info
			if ( $fld_groups && !is_null( $row->ug_group2 ) ) {
				$lastUserData['groups'][] = $row->ug_group2;
				$result->setIndexedTagName( $lastUserData['groups'], 'g' );
			}
		}

		if ( is_array( $lastUserData ) ) {
		        $fit = $result->addValue( array( 'query', $this->getModuleName() ),
		                        null, $lastUserData );
		        if ( !$fit ) {
		                $this->setContinueEnumParameter( 'from',
		                                $this->keyToTitle( $lastUserData['name'] ) );
		        }
		}

		$result->setIndexedTagName_internal( array( 'query', $this->getModuleName() ), 'u' );
	}

	public function getCacheMode( $params ) {
		return 'public';
	}

	public function getAllowedParams() {
		return array (
			'from' => null,
			'prefix' => null,
			'group' => array(
				ApiBase :: PARAM_TYPE => User::getAllGroups()
			),
			'prop' => array (
				ApiBase :: PARAM_ISMULTI => true,
				ApiBase :: PARAM_TYPE => array (
					'blockinfo',
					'groups',
					'editcount',
					'registration'
				)
			),
			'limit' => array (
				ApiBase :: PARAM_DFLT => 10,
				ApiBase :: PARAM_TYPE => 'limit',
				ApiBase :: PARAM_MIN => 1,
				ApiBase :: PARAM_MAX => ApiBase :: LIMIT_BIG1,
				ApiBase :: PARAM_MAX2 => ApiBase :: LIMIT_BIG2
			),
			'witheditsonly' => false,
		);
	}

	public function getParamDescription() {
		return array (
			'from' => 'The user name to start enumerating from.',
			'prefix' => 'Search for all page titles that begin with this value.',
			'group' => 'Limit users to a given group name',
			'prop' => array(
				'What pieces of information to include.',
				'`groups` property uses more server resources and may return fewer results than the limit.' ),
			'limit' => 'How many total user names to return.',
			'witheditsonly' => 'Only list users who have made edits',
		);
	}

	public function getDescription() {
		return 'Enumerate all registered users';
	}

	protected function getExamples() {
		return array (
			'api.php?action=query&list=allusers&aufrom=Y',
		);
	}

	public function getVersion() {
		return __CLASS__ . ': $Id: ApiQueryAllUsers.php 79562 2011-01-04 06:15:54Z tstarling $';
	}
}
