<?php
/**
 *
 *
 * Created on Sep 25, 2006
 *
 * Copyright © 2006 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

/**
 * This query action allows clients to retrieve a list of recently modified pages
 * that are part of the logged-in user's watchlist.
 *
 * @ingroup API
 */
class ApiQueryWatchlist extends ApiQueryGeneratorBase {

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

	public function execute() {
		$this->run();
	}

	public function executeGenerator( $resultPageSet ) {
		$this->run( $resultPageSet );
	}

	private $fld_ids = false, $fld_title = false, $fld_patrol = false,
		$fld_flags = false, $fld_timestamp = false, $fld_user = false,
		$fld_comment = false, $fld_parsedcomment = false, $fld_sizes = false,
		$fld_notificationtimestamp = false, $fld_userid = false,
		$fld_loginfo = false;

	/**
	 * @param ApiPageSet $resultPageSet
	 * @return void
	 */
	private function run( $resultPageSet = null ) {
		$this->selectNamedDB( 'watchlist', DB_SLAVE, 'watchlist' );

		$params = $this->extractRequestParams();

		$user = $this->getUser();
		$wlowner = $this->getWatchlistUser( $params );

		if ( !is_null( $params['prop'] ) && is_null( $resultPageSet ) ) {
			$prop = array_flip( $params['prop'] );

			$this->fld_ids = isset( $prop['ids'] );
			$this->fld_title = isset( $prop['title'] );
			$this->fld_flags = isset( $prop['flags'] );
			$this->fld_user = isset( $prop['user'] );
			$this->fld_userid = isset( $prop['userid'] );
			$this->fld_comment = isset( $prop['comment'] );
			$this->fld_parsedcomment = isset( $prop['parsedcomment'] );
			$this->fld_timestamp = isset( $prop['timestamp'] );
			$this->fld_sizes = isset( $prop['sizes'] );
			$this->fld_patrol = isset( $prop['patrol'] );
			$this->fld_notificationtimestamp = isset( $prop['notificationtimestamp'] );
			$this->fld_loginfo = isset( $prop['loginfo'] );

			if ( $this->fld_patrol ) {
				if ( !$user->useRCPatrol() && !$user->useNPPatrol() ) {
					$this->dieUsage( 'patrol property is not available', 'patrol' );
				}
			}
		}

		$this->addFields( array(
			'rc_id',
			'rc_namespace',
			'rc_title',
			'rc_timestamp',
			'rc_type',
			'rc_deleted',
		) );

		if ( is_null( $resultPageSet ) ) {
			$this->addFields( array(
				'rc_cur_id',
				'rc_this_oldid',
				'rc_last_oldid',
			) );

			$this->addFieldsIf( array( 'rc_type', 'rc_minor', 'rc_bot' ), $this->fld_flags );
			$this->addFieldsIf( 'rc_user', $this->fld_user || $this->fld_userid );
			$this->addFieldsIf( 'rc_user_text', $this->fld_user );
			$this->addFieldsIf( 'rc_comment', $this->fld_comment || $this->fld_parsedcomment );
			$this->addFieldsIf( 'rc_patrolled', $this->fld_patrol );
			$this->addFieldsIf( array( 'rc_old_len', 'rc_new_len' ), $this->fld_sizes );
			$this->addFieldsIf( 'wl_notificationtimestamp', $this->fld_notificationtimestamp );
			$this->addFieldsIf(
				array( 'rc_logid', 'rc_log_type', 'rc_log_action', 'rc_params' ),
				$this->fld_loginfo
			);
		} elseif ( $params['allrev'] ) {
			$this->addFields( 'rc_this_oldid' );
		} else {
			$this->addFields( 'rc_cur_id' );
		}

		$this->addTables( array(
			'recentchanges',
			'watchlist',
		) );

		$userId = $wlowner->getId();
		$this->addJoinConds( array( 'watchlist' => array( 'INNER JOIN',
			array(
				'wl_user' => $userId,
				'wl_namespace=rc_namespace',
				'wl_title=rc_title'
			)
		) ) );

		$db = $this->getDB();

		$this->addTimestampWhereRange( 'rc_timestamp', $params['dir'],
			$params['start'], $params['end'] );
		// Include in ORDER BY for uniqueness
		$this->addWhereRange( 'rc_id', $params['dir'], null, null );

		if ( !is_null( $params['continue'] ) ) {
			$cont = explode( '|', $params['continue'] );
			$this->dieContinueUsageIf( count( $cont ) != 2 );
			$op = ( $params['dir'] === 'newer' ? '>' : '<' );
			$continueTimestamp = $db->addQuotes( $db->timestamp( $cont[0] ) );
			$continueId = (int)$cont[1];
			$this->dieContinueUsageIf( $continueId != $cont[1] );
			$this->addWhere( "rc_timestamp $op $continueTimestamp OR " .
				"(rc_timestamp = $continueTimestamp AND " .
				"rc_id $op= $continueId)"
			);
		}

		$this->addWhereFld( 'wl_namespace', $params['namespace'] );

		if ( !$params['allrev'] ) {
			$this->addTables( 'page' );
			$this->addJoinConds( array( 'page' => array( 'LEFT JOIN', 'rc_cur_id=page_id' ) ) );
			$this->addWhere( 'rc_this_oldid=page_latest OR rc_type=' . RC_LOG );
		}

		if ( !is_null( $params['show'] ) ) {
			$show = array_flip( $params['show'] );

			/* Check for conflicting parameters. */
			if ( ( isset( $show['minor'] ) && isset( $show['!minor'] ) )
				|| ( isset( $show['bot'] ) && isset( $show['!bot'] ) )
				|| ( isset( $show['anon'] ) && isset( $show['!anon'] ) )
				|| ( isset( $show['patrolled'] ) && isset( $show['!patrolled'] ) )
				|| ( isset( $show['unread'] ) && isset( $show['!unread'] ) )
			) {
				$this->dieUsageMsg( 'show' );
			}

			// Check permissions.
			if ( isset( $show['patrolled'] ) || isset( $show['!patrolled'] ) ) {
				if ( !$user->useRCPatrol() && !$user->useNPPatrol() ) {
					$this->dieUsage(
						'You need the patrol right to request the patrolled flag',
						'permissiondenied'
					);
				}
			}

			/* Add additional conditions to query depending upon parameters. */
			$this->addWhereIf( 'rc_minor = 0', isset( $show['!minor'] ) );
			$this->addWhereIf( 'rc_minor != 0', isset( $show['minor'] ) );
			$this->addWhereIf( 'rc_bot = 0', isset( $show['!bot'] ) );
			$this->addWhereIf( 'rc_bot != 0', isset( $show['bot'] ) );
			$this->addWhereIf( 'rc_user = 0', isset( $show['anon'] ) );
			$this->addWhereIf( 'rc_user != 0', isset( $show['!anon'] ) );
			$this->addWhereIf( 'rc_patrolled = 0', isset( $show['!patrolled'] ) );
			$this->addWhereIf( 'rc_patrolled != 0', isset( $show['patrolled'] ) );
			$this->addWhereIf( 'wl_notificationtimestamp IS NOT NULL', isset( $show['unread'] ) );
			$this->addWhereIf( 'wl_notificationtimestamp IS NULL', isset( $show['!unread'] ) );
		}

		if ( !is_null( $params['type'] ) ) {
			try {
				$this->addWhereFld( 'rc_type', RecentChange::parseToRCType( $params['type'] ) );
			} catch ( MWException $e ) {
				ApiBase::dieDebug( __METHOD__, $e->getMessage() );
			}
		}

		if ( !is_null( $params['user'] ) && !is_null( $params['excludeuser'] ) ) {
			$this->dieUsage( 'user and excludeuser cannot be used together', 'user-excludeuser' );
		}
		if ( !is_null( $params['user'] ) ) {
			$this->addWhereFld( 'rc_user_text', $params['user'] );
		}
		if ( !is_null( $params['excludeuser'] ) ) {
			$this->addWhere( 'rc_user_text != ' . $db->addQuotes( $params['excludeuser'] ) );
		}

		// This is an index optimization for mysql, as done in the Special:Watchlist page
		$this->addWhereIf(
			"rc_timestamp > ''",
			!isset( $params['start'] ) && !isset( $params['end'] ) && $db->getType() == 'mysql'
		);

		// Paranoia: avoid brute force searches (bug 17342)
		if ( !is_null( $params['user'] ) || !is_null( $params['excludeuser'] ) ) {
			if ( !$user->isAllowed( 'deletedhistory' ) ) {
				$bitmask = Revision::DELETED_USER;
			} elseif ( !$user->isAllowedAny( 'suppressrevision', 'viewsuppressed' ) ) {
				$bitmask = Revision::DELETED_USER | Revision::DELETED_RESTRICTED;
			} else {
				$bitmask = 0;
			}
			if ( $bitmask ) {
				$this->addWhere( $this->getDB()->bitAnd( 'rc_deleted', $bitmask ) . " != $bitmask" );
			}
		}

		// LogPage::DELETED_ACTION hides the affected page, too. So hide those
		// entirely from the watchlist, or someone could guess the title.
		if ( !$user->isAllowed( 'deletedhistory' ) ) {
			$bitmask = LogPage::DELETED_ACTION;
		} elseif ( !$user->isAllowedAny( 'suppressrevision', 'viewsuppressed' ) ) {
			$bitmask = LogPage::DELETED_ACTION | LogPage::DELETED_RESTRICTED;
		} else {
			$bitmask = 0;
		}
		if ( $bitmask ) {
			$this->addWhere( $this->getDB()->makeList( array(
				'rc_type != ' . RC_LOG,
				$this->getDB()->bitAnd( 'rc_deleted', $bitmask ) . " != $bitmask",
			), LIST_OR ) );
		}

		$this->addOption( 'LIMIT', $params['limit'] + 1 );

		$ids = array();
		$count = 0;
		$res = $this->select( __METHOD__ );

		foreach ( $res as $row ) {
			if ( ++$count > $params['limit'] ) {
				// We've reached the one extra which shows that there are
				// additional pages to be had. Stop here...
				$this->setContinueEnumParameter( 'continue', "$row->rc_timestamp|$row->rc_id" );
				break;
			}

			if ( is_null( $resultPageSet ) ) {
				$vals = $this->extractRowInfo( $row );
				$fit = $this->getResult()->addValue( array( 'query', $this->getModuleName() ), null, $vals );
				if ( !$fit ) {
					$this->setContinueEnumParameter( 'continue', "$row->rc_timestamp|$row->rc_id" );
					break;
				}
			} else {
				if ( $params['allrev'] ) {
					$ids[] = intval( $row->rc_this_oldid );
				} else {
					$ids[] = intval( $row->rc_cur_id );
				}
			}
		}

		if ( is_null( $resultPageSet ) ) {
			$this->getResult()->setIndexedTagName_internal(
				array( 'query', $this->getModuleName() ),
				'item'
			);
		} elseif ( $params['allrev'] ) {
			$resultPageSet->populateFromRevisionIDs( $ids );
		} else {
			$resultPageSet->populateFromPageIDs( $ids );
		}
	}

	private function extractRowInfo( $row ) {
		/* Determine the title of the page that has been changed. */
		$title = Title::makeTitle( $row->rc_namespace, $row->rc_title );
		$user = $this->getUser();

		/* Our output data. */
		$vals = array();
		$type = intval( $row->rc_type );
		$vals['type'] = RecentChange::parseFromRCType( $type );
		$anyHidden = false;

		/* Create a new entry in the result for the title. */
		if ( $this->fld_title || $this->fld_ids ) {
			// These should already have been filtered out of the query, but just in case.
			if ( $type === RC_LOG && ( $row->rc_deleted & LogPage::DELETED_ACTION ) ) {
				$vals['actionhidden'] = '';
				$anyHidden = true;
			}
			if ( $type !== RC_LOG ||
				LogEventsList::userCanBitfield( $row->rc_deleted, LogPage::DELETED_ACTION, $user )
			) {
				if ( $this->fld_title ) {
					ApiQueryBase::addTitleInfo( $vals, $title );
				}
				if ( $this->fld_ids ) {
					$vals['pageid'] = intval( $row->rc_cur_id );
					$vals['revid'] = intval( $row->rc_this_oldid );
					$vals['old_revid'] = intval( $row->rc_last_oldid );
				}
			}
		}

		/* Add user data and 'anon' flag, if user is anonymous. */
		if ( $this->fld_user || $this->fld_userid ) {
			if ( $row->rc_deleted & Revision::DELETED_USER ) {
				$vals['userhidden'] = '';
				$anyHidden = true;
			}
			if ( Revision::userCanBitfield( $row->rc_deleted, Revision::DELETED_USER, $user ) ) {
				if ( $this->fld_userid ) {
					$vals['userid'] = $row->rc_user;
					// for backwards compatibility
					$vals['user'] = $row->rc_user;
				}

				if ( $this->fld_user ) {
					$vals['user'] = $row->rc_user_text;
				}

				if ( !$row->rc_user ) {
					$vals['anon'] = '';
				}
			}
		}

		/* Add flags, such as new, minor, bot. */
		if ( $this->fld_flags ) {
			if ( $row->rc_bot ) {
				$vals['bot'] = '';
			}
			if ( $row->rc_type == RC_NEW ) {
				$vals['new'] = '';
			}
			if ( $row->rc_minor ) {
				$vals['minor'] = '';
			}
		}

		/* Add sizes of each revision. (Only available on 1.10+) */
		if ( $this->fld_sizes ) {
			$vals['oldlen'] = intval( $row->rc_old_len );
			$vals['newlen'] = intval( $row->rc_new_len );
		}

		/* Add the timestamp. */
		if ( $this->fld_timestamp ) {
			$vals['timestamp'] = wfTimestamp( TS_ISO_8601, $row->rc_timestamp );
		}

		if ( $this->fld_notificationtimestamp ) {
			$vals['notificationtimestamp'] = ( $row->wl_notificationtimestamp == null )
				? ''
				: wfTimestamp( TS_ISO_8601, $row->wl_notificationtimestamp );
		}

		/* Add edit summary / log summary. */
		if ( $this->fld_comment || $this->fld_parsedcomment ) {
			if ( $row->rc_deleted & Revision::DELETED_COMMENT ) {
				$vals['commenthidden'] = '';
				$anyHidden = true;
			}
			if ( Revision::userCanBitfield( $row->rc_deleted, Revision::DELETED_COMMENT, $user ) ) {
				if ( $this->fld_comment && isset( $row->rc_comment ) ) {
					$vals['comment'] = $row->rc_comment;
				}

				if ( $this->fld_parsedcomment && isset( $row->rc_comment ) ) {
					$vals['parsedcomment'] = Linker::formatComment( $row->rc_comment, $title );
				}
			}
		}

		/* Add the patrolled flag */
		if ( $this->fld_patrol && $row->rc_patrolled == 1 ) {
			$vals['patrolled'] = '';
		}

		if ( $this->fld_patrol && ChangesList::isUnpatrolled( $row, $user ) ) {
			$vals['unpatrolled'] = '';
		}

		if ( $this->fld_loginfo && $row->rc_type == RC_LOG ) {
			if ( $row->rc_deleted & LogPage::DELETED_ACTION ) {
				$vals['actionhidden'] = '';
				$anyHidden = true;
			}
			if ( LogEventsList::userCanBitfield( $row->rc_deleted, LogPage::DELETED_ACTION, $user ) ) {
				$vals['logid'] = intval( $row->rc_logid );
				$vals['logtype'] = $row->rc_log_type;
				$vals['logaction'] = $row->rc_log_action;
				$logEntry = DatabaseLogEntry::newFromRow( (array)$row );
				ApiQueryLogEvents::addLogParams(
					$this->getResult(),
					$vals,
					$logEntry->getParameters(),
					$logEntry->getType(),
					$logEntry->getSubtype(),
					$logEntry->getTimestamp()
				);
			}
		}

		if ( $anyHidden && ( $row->rc_deleted & Revision::DELETED_RESTRICTED ) ) {
			$vals['suppressed'] = '';
		}

		return $vals;
	}

	public function getAllowedParams() {
		return array(
			'allrev' => false,
			'start' => array(
				ApiBase::PARAM_TYPE => 'timestamp'
			),
			'end' => array(
				ApiBase::PARAM_TYPE => 'timestamp'
			),
			'namespace' => array(
				ApiBase::PARAM_ISMULTI => true,
				ApiBase::PARAM_TYPE => 'namespace'
			),
			'user' => array(
				ApiBase::PARAM_TYPE => 'user',
			),
			'excludeuser' => array(
				ApiBase::PARAM_TYPE => 'user',
			),
			'dir' => array(
				ApiBase::PARAM_DFLT => 'older',
				ApiBase::PARAM_TYPE => array(
					'newer',
					'older'
				)
			),
			'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
			),
			'prop' => array(
				ApiBase::PARAM_ISMULTI => true,
				ApiBase::PARAM_DFLT => 'ids|title|flags',
				ApiBase::PARAM_TYPE => array(
					'ids',
					'title',
					'flags',
					'user',
					'userid',
					'comment',
					'parsedcomment',
					'timestamp',
					'patrol',
					'sizes',
					'notificationtimestamp',
					'loginfo',
				)
			),
			'show' => array(
				ApiBase::PARAM_ISMULTI => true,
				ApiBase::PARAM_TYPE => array(
					'minor',
					'!minor',
					'bot',
					'!bot',
					'anon',
					'!anon',
					'patrolled',
					'!patrolled',
					'unread',
					'!unread',
				)
			),
			'type' => array(
				ApiBase::PARAM_ISMULTI => true,
				ApiBase::PARAM_TYPE => array(
					'edit',
					'external',
					'new',
					'log',
				)
			),
			'owner' => array(
				ApiBase::PARAM_TYPE => 'user'
			),
			'token' => array(
				ApiBase::PARAM_TYPE => 'string'
			),
			'continue' => null,
		);
	}

	public function getParamDescription() {
		$p = $this->getModulePrefix();

		return array(
			'allrev' => 'Include multiple revisions of the same page within given timeframe',
			'start' => 'The timestamp to start enumerating from',
			'end' => 'The timestamp to end enumerating',
			'namespace' => 'Filter changes to only the given namespace(s)',
			'user' => 'Only list changes by this user',
			'excludeuser' => 'Don\'t list changes by this user',
			'dir' => $this->getDirectionDescription( $p ),
			'limit' => 'How many total results to return per request',
			'prop' => array(
				'Which additional items to get (non-generator mode only).',
				' ids                    - Adds revision ids and page ids',
				' title                  - Adds title of the page',
				' flags                  - Adds flags for the edit',
				' user                   - Adds the user who made the edit',
				' userid                 - Adds user id of whom made the edit',
				' comment                - Adds comment of the edit',
				' parsedcomment          - Adds parsed comment of the edit',
				' timestamp              - Adds timestamp of the edit',
				' patrol                 - Tags edits that are patrolled',
				' sizes                  - Adds the old and new lengths of the page',
				' notificationtimestamp  - Adds timestamp of when the user was last notified about the edit',
				' loginfo                - Adds log information where appropriate',
			),
			'show' => array(
				'Show only items that meet this criteria.',
				"For example, to see only minor edits done by logged-in users, set {$p}show=minor|!anon"
			),
			'type' => array(
				'Which types of changes to show',
				' edit           - Regular page edits',
				' external       - External changes',
				' new            - Page creations',
				' log            - Log entries',
			),
			'owner' => 'The name of the user whose watchlist you\'d like to access',
			'token' => 'Give a security token (settable in preferences) to ' .
				'allow access to another user\'s watchlist',
			'continue' => 'When more results are available, use this to continue',
		);
	}

	public function getDescription() {
		return "Get all recent changes to pages in the logged in user's watchlist.";
	}

	public function getExamples() {
		return array(
			'api.php?action=query&list=watchlist',
			'api.php?action=query&list=watchlist&wlprop=ids|title|timestamp|user|comment',
			'api.php?action=query&list=watchlist&wlallrev=&wlprop=ids|title|timestamp|user|comment',
			'api.php?action=query&generator=watchlist&prop=info',
			'api.php?action=query&generator=watchlist&gwlallrev=&prop=revisions&rvprop=timestamp|user',
			'api.php?action=query&list=watchlist&wlowner=Bob_Smith&wltoken=123ABC'
		);
	}

	public function getHelpUrls() {
		return 'https://www.mediawiki.org/wiki/API:Watchlist';
	}
}