<?php

/**
 * API for MediaWiki 1.14+
 *
 * Created on Jun 18, 2012
 *
 * Copyright © 2012 Brad Jorsch
 *
 * 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
 */

/**
 * API interface for setting the wl_notificationtimestamp field
 * @ingroup API
 */
class ApiSetNotificationTimestamp extends ApiBase {

	private $mPageSet;

	public function execute() {
		$user = $this->getUser();

		if ( $user->isAnon() ) {
			$this->dieUsage( 'Anonymous users cannot use watchlist change notifications', 'notloggedin' );
		}
		if ( !$user->isAllowed( 'editmywatchlist' ) ) {
			$this->dieUsage( 'You don\'t have permission to edit your watchlist', 'permissiondenied' );
		}

		$params = $this->extractRequestParams();
		$this->requireMaxOneParameter( $params, 'timestamp', 'torevid', 'newerthanrevid' );

		$this->getResult()->beginContinuation( $params['continue'], array(), array() );

		$pageSet = $this->getPageSet();
		if ( $params['entirewatchlist'] && $pageSet->getDataSource() !== null ) {
			$this->dieUsage(
				"Cannot use 'entirewatchlist' at the same time as '{$pageSet->getDataSource()}'",
				'multisource'
			);
		}

		$dbw = wfGetDB( DB_MASTER, 'api' );

		$timestamp = null;
		if ( isset( $params['timestamp'] ) ) {
			$timestamp = $dbw->timestamp( $params['timestamp'] );
		}

		if ( !$params['entirewatchlist'] ) {
			$pageSet->execute();
		}

		if ( isset( $params['torevid'] ) ) {
			if ( $params['entirewatchlist'] || $pageSet->getGoodTitleCount() > 1 ) {
				$this->dieUsage( 'torevid may only be used with a single page', 'multpages' );
			}
			$title = reset( $pageSet->getGoodTitles() );
			if ( $title ) {
				$timestamp = Revision::getTimestampFromId( $title, $params['torevid'] );
				if ( $timestamp ) {
					$timestamp = $dbw->timestamp( $timestamp );
				} else {
					$timestamp = null;
				}
			}
		} elseif ( isset( $params['newerthanrevid'] ) ) {
			if ( $params['entirewatchlist'] || $pageSet->getGoodTitleCount() > 1 ) {
				$this->dieUsage( 'newerthanrevid may only be used with a single page', 'multpages' );
			}
			$title = reset( $pageSet->getGoodTitles() );
			if ( $title ) {
				$revid = $title->getNextRevisionID( $params['newerthanrevid'] );
				if ( $revid ) {
					$timestamp = $dbw->timestamp( Revision::getTimestampFromId( $title, $revid ) );
				} else {
					$timestamp = null;
				}
			}
		}

		$apiResult = $this->getResult();
		$result = array();
		if ( $params['entirewatchlist'] ) {
			// Entire watchlist mode: Just update the thing and return a success indicator
			$dbw->update( 'watchlist', array( 'wl_notificationtimestamp' => $timestamp ),
				array( 'wl_user' => $user->getID() ),
				__METHOD__
			);

			$result['notificationtimestamp'] = is_null( $timestamp )
				? ''
				: wfTimestamp( TS_ISO_8601, $timestamp );
		} else {
			// First, log the invalid titles
			foreach ( $pageSet->getInvalidTitles() as $title ) {
				$r = array();
				$r['title'] = $title;
				$r['invalid'] = '';
				$result[] = $r;
			}
			foreach ( $pageSet->getMissingPageIDs() as $p ) {
				$page = array();
				$page['pageid'] = $p;
				$page['missing'] = '';
				$page['notwatched'] = '';
				$result[] = $page;
			}
			foreach ( $pageSet->getMissingRevisionIDs() as $r ) {
				$rev = array();
				$rev['revid'] = $r;
				$rev['missing'] = '';
				$rev['notwatched'] = '';
				$result[] = $rev;
			}

			if ( $pageSet->getTitles() ) {
				// Now process the valid titles
				$lb = new LinkBatch( $pageSet->getTitles() );
				$dbw->update( 'watchlist', array( 'wl_notificationtimestamp' => $timestamp ),
					array( 'wl_user' => $user->getID(), $lb->constructSet( 'wl', $dbw ) ),
					__METHOD__
				);

				// Query the results of our update
				$timestamps = array();
				$res = $dbw->select(
					'watchlist',
					array( 'wl_namespace', 'wl_title', 'wl_notificationtimestamp' ),
					array( 'wl_user' => $user->getID(), $lb->constructSet( 'wl', $dbw ) ),
					__METHOD__
				);
				foreach ( $res as $row ) {
					$timestamps[$row->wl_namespace][$row->wl_title] = $row->wl_notificationtimestamp;
				}

				// Now, put the valid titles into the result
				/** @var $title Title */
				foreach ( $pageSet->getTitles() as $title ) {
					$ns = $title->getNamespace();
					$dbkey = $title->getDBkey();
					$r = array(
						'ns' => intval( $ns ),
						'title' => $title->getPrefixedText(),
					);
					if ( !$title->exists() ) {
						$r['missing'] = '';
					}
					if ( isset( $timestamps[$ns] ) && array_key_exists( $dbkey, $timestamps[$ns] ) ) {
						$r['notificationtimestamp'] = '';
						if ( $timestamps[$ns][$dbkey] !== null ) {
							$r['notificationtimestamp'] = wfTimestamp( TS_ISO_8601, $timestamps[$ns][$dbkey] );
						}
					} else {
						$r['notwatched'] = '';
					}
					$result[] = $r;
				}
			}

			$apiResult->setIndexedTagName( $result, 'page' );
		}
		$apiResult->addValue( null, $this->getModuleName(), $result );

		$apiResult->endContinuation();
	}

	/**
	 * Get a cached instance of an ApiPageSet object
	 * @return ApiPageSet
	 */
	private function getPageSet() {
		if ( !isset( $this->mPageSet ) ) {
			$this->mPageSet = new ApiPageSet( $this );
		}

		return $this->mPageSet;
	}

	public function mustBePosted() {
		return true;
	}

	public function isWriteMode() {
		return true;
	}

	public function needsToken() {
		return 'csrf';
	}

	public function getAllowedParams( $flags = 0 ) {
		$result = array(
			'entirewatchlist' => array(
				ApiBase::PARAM_TYPE => 'boolean'
			),
			'timestamp' => array(
				ApiBase::PARAM_TYPE => 'timestamp'
			),
			'torevid' => array(
				ApiBase::PARAM_TYPE => 'integer'
			),
			'newerthanrevid' => array(
				ApiBase::PARAM_TYPE => 'integer'
			),
			'continue' => '',
		);
		if ( $flags ) {
			$result += $this->getPageSet()->getFinalParams( $flags );
		}

		return $result;
	}

	public function getParamDescription() {
		return $this->getPageSet()->getFinalParamDescription() + array(
			'entirewatchlist' => 'Work on all watched pages',
			'timestamp' => 'Timestamp to which to set the notification timestamp',
			'torevid' => 'Revision to set the notification timestamp to (one page only)',
			'newerthanrevid' => 'Revision to set the notification timestamp newer than (one page only)',
			'continue' => 'When more results are available, use this to continue',
		);
	}

	public function getDescription() {
		return array( 'Update the notification timestamp for watched pages.',
			'This affects the highlighting of changed pages in the watchlist and history,',
			'and the sending of email when the "Email me when a page on my watchlist is',
			'changed" preference is enabled.'
		);
	}

	public function getExamples() {
		return array(
			'api.php?action=setnotificationtimestamp&entirewatchlist=&token=123ABC'
				=> 'Reset the notification status for the entire watchlist',
			'api.php?action=setnotificationtimestamp&titles=Main_page&token=123ABC'
				=> 'Reset the notification status for "Main page"',
			'api.php?action=setnotificationtimestamp&titles=Main_page&' .
				'timestamp=2012-01-01T00:00:00Z&token=123ABC'
				=> 'Set the notification timestamp for "Main page" so all edits ' .
					'since 1 January 2012 are unviewed',
		);
	}

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