Fix regression in even sizing of diff columns; forgot to restore a couple bits I...

[mediawiki.git] / includes / Image.php

<?php
/**
 */

/**
 * NOTE FOR WINDOWS USERS:
 * To enable EXIF functions, add the folloing lines to the
 * "Windows extensions" section of php.ini:
 *
 * extension=extensions/php_mbstring.dll
 * extension=extensions/php_exif.dll
 */

/**
 * Bump this number when serialized cache records may be incompatible.
 */
define( 'MW_IMAGE_VERSION', 2 );

/**
 * Class to represent an image
 *
 * Provides methods to retrieve paths (physical, logical, URL),
 * to generate thumbnails or for uploading.
 *
 * @addtogroup Media
 */
class Image
{
        const DELETED_FILE = 1;
        const DELETED_COMMENT = 2;
        const DELETED_USER = 4;
        const DELETED_RESTRICTED = 8;
        const RENDER_NOW = 1;
    
        /**#@+
         * @private
         */
        var     $name,          # name of the image (constructor)
                $imagePath,     # Path of the image (loadFromXxx)
                $url,           # Image URL (accessor)
                $title,         # Title object for this image (constructor)
                $fileExists,    # does the image file exist on disk? (loadFromXxx)
                $fromSharedDirectory, # load this image from $wgSharedUploadDirectory (loadFromXxx)
                $historyLine,   # Number of line to return by nextHistoryLine() (constructor)
                $historyRes,    # result of the query for the image's history (nextHistoryLine)
                $width,         # \
                $height,        #  |
                $bits,          #   --- returned by getimagesize (loadFromXxx)
                $attr,          # /
                $type,          # MEDIATYPE_xxx (bitmap, drawing, audio...)
                $mime,          # MIME type, determined by MimeMagic::guessMimeType
                $extension,     # The file extension (constructor)
                $size,          # Size in bytes (loadFromXxx)
                $metadata,      # Metadata
                $dataLoaded,    # Whether or not all this has been loaded from the database (loadFromXxx)
                $page,          # Page to render when creating thumbnails
                $lastError;     # Error string associated with a thumbnail display error


        /**#@-*/

        /**
         * Create an Image object from an image name
         *
         * @param string $name name of the image, used to create a title object using Title::makeTitleSafe
         * @public
         */
        public static function newFromName( $name ) {
                $title = Title::makeTitleSafe( NS_IMAGE, $name );
                if ( is_object( $title ) ) {
                        return new Image( $title );
                } else {
                        return NULL;
                }
        }

        /**
         * Obsolete factory function, use constructor
         * @deprecated
         */
        function newFromTitle( $title ) {
                return new Image( $title );
        }

        function Image( $title ) {
                if( !is_object( $title ) ) {
                        throw new MWException( 'Image constructor given bogus title.' );
                }
                $this->title =& $title;
                $this->name = $title->getDBkey();
                $this->metadata = '';

                $n = strrpos( $this->name, '.' );
                $this->extension = Image::normalizeExtension( $n ?
                        substr( $this->name, $n + 1 ) : '' );
                $this->historyLine = 0;

                $this->dataLoaded = false;
        }

        /**
         * Normalize a file extension to the common form, and ensure it's clean.
         * Extensions with non-alphanumeric characters will be discarded.
         *
         * @param $ext string (without the .)
         * @return string
         */
        static function normalizeExtension( $ext ) {
                $lower = strtolower( $ext );
                $squish = array(
                        'htm' => 'html',
                        'jpeg' => 'jpg',
                        'mpeg' => 'mpg',
                        'tiff' => 'tif' );
                if( isset( $squish[$lower] ) ) {
                        return $squish[$lower];
                } elseif( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
                        return $lower;
                } else {
                        return '';
                }
        }

        /**
         * Get the memcached keys
         * Returns an array, first element is the local cache key, second is the shared cache key, if there is one
         */
        function getCacheKeys( ) {
                global $wgUseSharedUploads, $wgSharedUploadDBname, $wgCacheSharedUploads;

                $hashedName = md5($this->name);
                $keys = array( wfMemcKey( 'Image', $hashedName ) );
                if ( $wgUseSharedUploads && $wgSharedUploadDBname && $wgCacheSharedUploads ) {
                        $keys[] = wfForeignMemcKey( $wgSharedUploadDBname, false, 'Image', $hashedName );
                }
                return $keys;
        }

        /**
         * Try to load image metadata from memcached. Returns true on success.
         */
        function loadFromCache() {
                global $wgUseSharedUploads, $wgMemc;
                wfProfileIn( __METHOD__ );
                $this->dataLoaded = false;
                $keys = $this->getCacheKeys();
                $cachedValues = $wgMemc->get( $keys[0] );

                // Check if the key existed and belongs to this version of MediaWiki
                if (!empty($cachedValues) && is_array($cachedValues)
                  && isset($cachedValues['version']) && ( $cachedValues['version'] == MW_IMAGE_VERSION )
                  && isset( $cachedValues['mime'] ) && isset( $cachedValues['metadata'] ) )
                {
                        if ( $wgUseSharedUploads && $cachedValues['fromShared']) {
                                # if this is shared file, we need to check if image
                                # in shared repository has not changed
                                if ( isset( $keys[1] ) ) {
                                        $commonsCachedValues = $wgMemc->get( $keys[1] );
                                        if (!empty($commonsCachedValues) && is_array($commonsCachedValues)
                                          && isset($commonsCachedValues['version'])
                                          && ( $commonsCachedValues['version'] == MW_IMAGE_VERSION )
                                          && isset($commonsCachedValues['mime'])) {
                                                wfDebug( "Pulling image metadata from shared repository cache\n" );
                                                $this->name = $commonsCachedValues['name'];
                                                $this->imagePath = $commonsCachedValues['imagePath'];
                                                $this->fileExists = $commonsCachedValues['fileExists'];
                                                $this->width = $commonsCachedValues['width'];
                                                $this->height = $commonsCachedValues['height'];
                                                $this->bits = $commonsCachedValues['bits'];
                                                $this->type = $commonsCachedValues['type'];
                                                $this->mime = $commonsCachedValues['mime'];
                                                $this->metadata = $commonsCachedValues['metadata'];
                                                $this->size = $commonsCachedValues['size'];
                                                $this->fromSharedDirectory = true;
                                                $this->dataLoaded = true;
                                                $this->imagePath = $this->getFullPath(true);
                                        }
                                }
                        } else {
                                wfDebug( "Pulling image metadata from local cache\n" );
                                $this->name = $cachedValues['name'];
                                $this->imagePath = $cachedValues['imagePath'];
                                $this->fileExists = $cachedValues['fileExists'];
                                $this->width = $cachedValues['width'];
                                $this->height = $cachedValues['height'];
                                $this->bits = $cachedValues['bits'];
                                $this->type = $cachedValues['type'];
                                $this->mime = $cachedValues['mime'];
                                $this->metadata = $cachedValues['metadata'];
                                $this->size = $cachedValues['size'];
                                $this->fromSharedDirectory = false;
                                $this->dataLoaded = true;
                                $this->imagePath = $this->getFullPath();
                        }
                }
                if ( $this->dataLoaded ) {
                        wfIncrStats( 'image_cache_hit' );
                } else {
                        wfIncrStats( 'image_cache_miss' );
                }

                wfProfileOut( __METHOD__ );
                return $this->dataLoaded;
        }

        /**
         * Save the image metadata to memcached
         */
        function saveToCache() {
                global $wgMemc, $wgUseSharedUploads;
                $this->load();
                $keys = $this->getCacheKeys();
                // We can't cache negative metadata for non-existent files,
                // because if the file later appears in commons, the local
                // keys won't be purged.
                if ( $this->fileExists || !$wgUseSharedUploads ) {
                        $cachedValues = array(
                                'version'    => MW_IMAGE_VERSION,
                                'name'       => $this->name,
                                'imagePath'  => $this->imagePath,
                                'fileExists' => $this->fileExists,
                                'fromShared' => $this->fromSharedDirectory,
                                'width'      => $this->width,
                                'height'     => $this->height,
                                'bits'       => $this->bits,
                                'type'       => $this->type,
                                'mime'       => $this->mime,
                                'metadata'   => $this->metadata,
                                'size'       => $this->size );

                        $wgMemc->set( $keys[0], $cachedValues, 60 * 60 * 24 * 7 ); // A week
                } else {
                        // However we should clear them, so they aren't leftover
                        // if we've deleted the file.
                        $wgMemc->delete( $keys[0] );
                }
        }

        /**
         * Load metadata from the file itself
         */
        function loadFromFile() {
                global $wgUseSharedUploads, $wgSharedUploadDirectory, $wgContLang;
                wfProfileIn( __METHOD__ );
                $this->imagePath = $this->getFullPath();
                $this->fileExists = file_exists( $this->imagePath );
                $this->fromSharedDirectory = false;
                $gis = array();

                if (!$this->fileExists) wfDebug(__METHOD__.': '.$this->imagePath." not found locally!\n");

                # If the file is not found, and a shared upload directory is used, look for it there.
                if (!$this->fileExists && $wgUseSharedUploads && $wgSharedUploadDirectory) {
                        # In case we're on a wgCapitalLinks=false wiki, we
                        # capitalize the first letter of the filename before
                        # looking it up in the shared repository.
                        $sharedImage = Image::newFromName( $wgContLang->ucfirst($this->name) );
                        $this->fileExists = $sharedImage && file_exists( $sharedImage->getFullPath(true) );
                        if ( $this->fileExists ) {
                                $this->name = $sharedImage->name;
                                $this->imagePath = $this->getFullPath(true);
                                $this->fromSharedDirectory = true;
                        }
                }


                if ( $this->fileExists ) {
                        $magic=& MimeMagic::singleton();

                        $this->mime = $magic->guessMimeType($this->imagePath,true);
                        $this->type = $magic->getMediaType($this->imagePath,$this->mime);
                        $handler = MediaHandler::getHandler( $this->mime );

                        # Get size in bytes
                        $this->size = filesize( $this->imagePath );

                        # Height, width and metadata
                        if ( $handler ) {
                                $gis = $handler->getImageSize( $this, $this->imagePath );
                                $this->metadata = $handler->getMetadata( $this, $this->imagePath );
                        } else {
                                $gis = false;
                                $this->metadata = '';
                        }

                        wfDebug(__METHOD__.': '.$this->imagePath." loaded, ".$this->size." bytes, ".$this->mime.".\n");
                }
                else {
                        $this->mime = NULL;
                        $this->type = MEDIATYPE_UNKNOWN;
                        $this->metadata = '';
                        wfDebug(__METHOD__.': '.$this->imagePath." NOT FOUND!\n");
                }

                if( $gis ) {
                        $this->width = $gis[0];
                        $this->height = $gis[1];
                } else {
                        $this->width = 0;
                        $this->height = 0;
                }

                #NOTE: $gis[2] contains a code for the image type. This is no longer used.

                #NOTE: we have to set this flag early to avoid load() to be called
                # be some of the functions below. This may lead to recursion or other bad things!
                # as ther's only one thread of execution, this should be safe anyway.
                $this->dataLoaded = true;

                if ( isset( $gis['bits'] ) )  $this->bits = $gis['bits'];
                else $this->bits = 0;

                wfProfileOut( __METHOD__ );
        }

        /**
         * Load image metadata from the DB
         */
        function loadFromDB() {
                global $wgUseSharedUploads, $wgSharedUploadDBname, $wgSharedUploadDBprefix, $wgContLang;
                wfProfileIn( __METHOD__ );

                $dbr = wfGetDB( DB_SLAVE );

                $row = $dbr->selectRow( 'image',
                        array( 'img_size', 'img_width', 'img_height', 'img_bits',
                               'img_media_type', 'img_major_mime', 'img_minor_mime', 'img_metadata' ),
                        array( 'img_name' => $this->name ), __METHOD__ );
                if ( $row ) {
                        $this->fromSharedDirectory = false;
                        $this->fileExists = true;
                        $this->loadFromRow( $row );
                        $this->imagePath = $this->getFullPath();
                        // Check for rows from a previous schema, quietly upgrade them
                        $this->maybeUpgradeRow();
                } elseif ( $wgUseSharedUploads && $wgSharedUploadDBname ) {
                        # In case we're on a wgCapitalLinks=false wiki, we
                        # capitalize the first letter of the filename before
                        # looking it up in the shared repository.
                        $name = $wgContLang->ucfirst($this->name);
                        $dbc = Image::getCommonsDB();

                        $row = $dbc->selectRow( "`$wgSharedUploadDBname`.{$wgSharedUploadDBprefix}image",
                                array(
                                        'img_size', 'img_width', 'img_height', 'img_bits',
                                        'img_media_type', 'img_major_mime', 'img_minor_mime', 'img_metadata' ),
                                array( 'img_name' => $name ), __METHOD__ );
                        if ( $row ) {
                                $this->fromSharedDirectory = true;
                                $this->fileExists = true;
                                $this->imagePath = $this->getFullPath(true);
                                $this->name = $name;
                                $this->loadFromRow( $row );

                                // Check for rows from a previous schema, quietly upgrade them
                                $this->maybeUpgradeRow();
                        }
                }

                if ( !$row ) {
                        $this->size = 0;
                        $this->width = 0;
                        $this->height = 0;
                        $this->bits = 0;
                        $this->type = 0;
                        $this->fileExists = false;
                        $this->fromSharedDirectory = false;
                        $this->metadata = '';
                        $this->mime = false;
                }

                # Unconditionally set loaded=true, we don't want the accessors constantly rechecking
                $this->dataLoaded = true;
                wfProfileOut( __METHOD__ );
        }

        /*
         * Load image metadata from a DB result row
         */
        function loadFromRow( &$row ) {
                $this->size = $row->img_size;
                $this->width = $row->img_width;
                $this->height = $row->img_height;
                $this->bits = $row->img_bits;
                $this->type = $row->img_media_type;

                $major= $row->img_major_mime;
                $minor= $row->img_minor_mime;

                if (!$major) $this->mime = "unknown/unknown";
                else {
                        if (!$minor) $minor= "unknown";
                        $this->mime = $major.'/'.$minor;
                }
                $this->metadata = $row->img_metadata;

                $this->dataLoaded = true;
        }

        /**
         * Load image metadata from cache or DB, unless already loaded
         */
        function load() {
                global $wgSharedUploadDBname, $wgUseSharedUploads;
                if ( !$this->dataLoaded ) {
                        if ( !$this->loadFromCache() ) {
                                $this->loadFromDB();
                                if ( !$wgSharedUploadDBname && $wgUseSharedUploads ) {
                                        $this->loadFromFile();
                                } elseif ( $this->fileExists || !$wgUseSharedUploads ) {
                                        // We can do negative caching for local images, because the cache
                                        // will be purged on upload. But we can't do it when shared images
                                        // are enabled, since updates to that won't purge foreign caches.
                                        $this->saveToCache();
                                } 
                        }
                        $this->dataLoaded = true;
                }
        }

        /**
         * Upgrade a row if it needs it
         */
        function maybeUpgradeRow() {
                if ( is_null($this->type) || $this->mime == 'image/svg' ) {
                        $this->upgradeRow();
                } else {
                        $handler = $this->getHandler();
                        if ( $handler && !$handler->isMetadataValid( $this, $this->metadata ) ) {
                                $this->upgradeRow();
                        }
                }
        }

        /**
         * Fix assorted version-related problems with the image row by reloading it from the file
         */
        function upgradeRow() {
                global $wgDBname, $wgSharedUploadDBname;
                wfProfileIn( __METHOD__ );

                $this->loadFromFile();

                if ( $this->fromSharedDirectory ) {
                        if ( !$wgSharedUploadDBname ) {
                                wfProfileOut( __METHOD__ );
                                return;
                        }

                        // Write to the other DB using selectDB, not database selectors
                        // This avoids breaking replication in MySQL
                        $dbw = Image::getCommonsDB();
                } else {
                        $dbw = wfGetDB( DB_MASTER );
                }

                list( $major, $minor ) = self::splitMime( $this->mime );

                wfDebug(__METHOD__.': upgrading '.$this->name." to the current schema\n");

                $dbw->update( 'image',
                        array(
                                'img_width' => $this->width,
                                'img_height' => $this->height,
                                'img_bits' => $this->bits,
                                'img_media_type' => $this->type,
                                'img_major_mime' => $major,
                                'img_minor_mime' => $minor,
                                'img_metadata' => $this->metadata,
                        ), array( 'img_name' => $this->name ), __METHOD__
                );
                if ( $this->fromSharedDirectory ) {
                        $dbw->selectDB( $wgDBname );
                }
                wfProfileOut( __METHOD__ );
        }

        /**
         * Split an internet media type into its two components; if not
         * a two-part name, set the minor type to 'unknown'.
         *
         * @param $mime "text/html" etc
         * @return array ("text", "html") etc
         */
        static function splitMime( $mime ) {
                if( strpos( $mime, '/' ) !== false ) {
                        return explode( '/', $mime, 2 );
                } else {
                        return array( $mime, 'unknown' );
                }
        }

        /**
         * Return the name of this image
         * @public
         */
        function getName() {
                return $this->name;
        }

        /**
         * Return the associated title object
         * @public
         */
        function getTitle() {
                return $this->title;
        }

        /**
         * Return the URL of the image file
         * @public
         */
        function getURL() {
                if ( !$this->url ) {
                        $this->load();
                        if($this->fileExists) {
                                $this->url = Image::imageUrl( $this->name, $this->fromSharedDirectory );
                        } else {
                                $this->url = '';
                        }
                }
                return $this->url;
        }

        function getViewURL() {
                if( $this->mustRender()) {
                        if( $this->canRender() ) {
                                return $this->createThumb( $this->getWidth() );
                        }
                        else {
                                wfDebug('Image::getViewURL(): supposed to render '.$this->name.' ('.$this->mime."), but can't!\n");
                                return $this->getURL(); #hm... return NULL?
                        }
                } else {
                        return $this->getURL();
                }
        }

        /**
         * Return the image path of the image in the
         * local file system as an absolute path
         * @public
         */
        function getImagePath() {
                $this->load();
                return $this->imagePath;
        }

        /**
         * Return the width of the image
         *
         * Returns false on error
         * @public
         */
        function getWidth( $page = 1 ) {
                $this->load();
                if ( $this->isMultipage() ) {
                        $dim = $this->getHandler()->getPageDimensions( $this, $page );
                        if ( $dim ) {
                                return $dim['width'];
                        } else {
                                return false;
                        }
                } else {
                        return $this->width;
                }
        }

        /**
         * Return the height of the image
         *
         * Returns false on error
         * @public
         */
        function getHeight( $page = 1 ) {
                $this->load();
                if ( $this->isMultipage() ) {
                        $dim = $this->getHandler()->getPageDimensions( $this, $page );
                        if ( $dim ) {
                                return $dim['height'];
                        } else {
                                return false;
                        }
                } else {
                        return $this->height;
                }
        }

        /**
         * Get handler-specific metadata
         */
        function getMetadata() {
                $this->load();
                return $this->metadata;
        }

        /**
         * Return the size of the image file, in bytes
         * @public
         */
        function getSize() {
                $this->load();
                return $this->size;
        }

        /**
         * Returns the mime type of the file.
         */
        function getMimeType() {
                $this->load();
                return $this->mime;
        }

        /**
         * Return the type of the media in the file.
         * Use the value returned by this function with the MEDIATYPE_xxx constants.
         */
        function getMediaType() {
                $this->load();
                return $this->type;
        }

        /**
         * Checks if the file can be presented to the browser as a bitmap.
         *
         * Currently, this checks if the file is an image format
         * that can be converted to a format
         * supported by all browsers (namely GIF, PNG and JPEG),
         * or if it is an SVG image and SVG conversion is enabled.
         *
         * @todo remember the result of this check.
         */
        function canRender() {
                $handler = $this->getHandler();
                return $handler && $handler->canRender();
        }

        /**
         * Return true if the file is of a type that can't be directly
         * rendered by typical browsers and needs to be re-rasterized.
         *
         * This returns true for everything but the bitmap types
         * supported by all browsers, i.e. JPEG; GIF and PNG. It will
         * also return true for any non-image formats.
         *
         * @return bool
         */
        function mustRender() {
                $handler = $this->getHandler();
                return $handler && $handler->mustRender();
        }

        /**
         * Determines if this media file may be shown inline on a page.
         *
         * This is currently synonymous to canRender(), but this could be
         * extended to also allow inline display of other media,
         * like flash animations or videos. If you do so, please keep in mind that
         * that could be a security risk.
         */
        function allowInlineDisplay() {
                return $this->canRender();
        }

        /**
         * Determines if this media file is in a format that is unlikely to
         * contain viruses or malicious content. It uses the global
         * $wgTrustedMediaFormats list to determine if the file is safe.
         *
         * This is used to show a warning on the description page of non-safe files.
         * It may also be used to disallow direct [[media:...]] links to such files.
         *
         * Note that this function will always return true if allowInlineDisplay()
         * or isTrustedFile() is true for this file.
         */
        function isSafeFile() {
                if ($this->allowInlineDisplay()) return true;
                if ($this->isTrustedFile()) return true;

                global $wgTrustedMediaFormats;

                $type= $this->getMediaType();
                $mime= $this->getMimeType();
                #wfDebug("Image::isSafeFile: type= $type, mime= $mime\n");

                if (!$type || $type===MEDIATYPE_UNKNOWN) return false; #unknown type, not trusted
                if ( in_array( $type, $wgTrustedMediaFormats) ) return true;

                if ($mime==="unknown/unknown") return false; #unknown type, not trusted
                if ( in_array( $mime, $wgTrustedMediaFormats) ) return true;

                return false;
        }

        /** Returns true if the file is flagged as trusted. Files flagged that way
        * can be linked to directly, even if that is not allowed for this type of
        * file normally.
        *
        * This is a dummy function right now and always returns false. It could be
        * implemented to extract a flag from the database. The trusted flag could be
        * set on upload, if the user has sufficient privileges, to bypass script-
        * and html-filters. It may even be coupled with cryptographics signatures
        * or such.
        */
        function isTrustedFile() {
                #this could be implemented to check a flag in the databas,
                #look for signatures, etc
                return false;
        }

        /**
         * Return the escapeLocalURL of this image
         * @public
         */
        function getEscapeLocalURL( $query=false) {
                return $this->getTitle()->escapeLocalURL( $query );
        }

        /**
         * Return the escapeFullURL of this image
         * @public
         */
        function getEscapeFullURL() {
                $this->getTitle();
                return $this->title->escapeFullURL();
        }

        /**
         * Return the URL of an image, provided its name.
         *
         * @param string $name  Name of the image, without the leading "Image:"
         * @param boolean $fromSharedDirectory  Should this be in $wgSharedUploadPath?
         * @return string URL of $name image
         * @public
         */
        static function imageUrl( $name, $fromSharedDirectory = false ) {
                global $wgUploadPath,$wgUploadBaseUrl,$wgSharedUploadPath;
                if($fromSharedDirectory) {
                        $base = '';
                        $path = $wgSharedUploadPath;
                } else {
                        $base = $wgUploadBaseUrl;
                        $path = $wgUploadPath;
                }
                $url = "{$base}{$path}" .  wfGetHashPath($name, $fromSharedDirectory) . "{$name}";
                return wfUrlencode( $url );
        }

        /**
         * Returns true if the image file exists on disk.
         * @return boolean Whether image file exist on disk.
         * @public
         */
        function exists() {
                $this->load();
                return $this->fileExists;
        }

        /**
         * @todo document
         * @private
         */
        function thumbUrlFromName( $thumbName, $subdir = 'thumb' ) {
                global $wgUploadPath, $wgUploadBaseUrl, $wgSharedUploadPath;
                if($this->fromSharedDirectory) {
                        $base = '';
                        $path = $wgSharedUploadPath;
                } else {
                        $base = $wgUploadBaseUrl;
                        $path = $wgUploadPath;
                }
                if ( Image::isHashed( $this->fromSharedDirectory ) ) {
                        $hashdir = wfGetHashPath($this->name, $this->fromSharedDirectory) .
                        wfUrlencode( $this->name );
                } else {
                        $hashdir = '';
                }
                $url = "{$base}{$path}/{$subdir}{$hashdir}/" . wfUrlencode( $thumbName );
                return $url;
        }

        /**
         * @deprecated Use $image->transform()->getUrl() or thumbUrlFromName()
         */
        function thumbUrl( $width, $subdir = 'thumb' ) {
                $name = $this->thumbName( array( 'width' => $width ) );
                if ( strval( $name ) !== '' ) {
                        return array( false, $this->thumbUrlFromName( $name, $subdir ) );
                } else {
                        return array( false, false );
                }
        }

        function getTransformScript() {
                global $wgSharedThumbnailScriptPath, $wgThumbnailScriptPath;
                if ( $this->fromSharedDirectory ) {
                        $script = $wgSharedThumbnailScriptPath;
                } else {
                        $script = $wgThumbnailScriptPath;
                }
                if ( $script ) {
                        return "$script?f=" . urlencode( $this->name );
                } else {
                        return false;
                }
        }

        /**
         * Get a ThumbnailImage which is the same size as the source
         */
        function getUnscaledThumb( $page = false ) {
                if ( $page ) {
                        $params = array(
                                'page' => $page,
                                'width' => $this->getWidth( $page )
                        );
                } else {
                        $params = array( 'width' => $this->getWidth() );
                }
                return $this->transform( $params );
        }

        /**
         * Return the file name of a thumbnail with the specified parameters
         *
         * @param array $params Handler-specific parameters
         * @private
         */
        function thumbName( $params ) {
                $handler = $this->getHandler();
                if ( !$handler ) {
                        return null;
                }
                list( $thumbExt, /* $thumbMime */ ) = self::getThumbType( $this->extension, $this->mime );
                $thumbName = $handler->makeParamString( $params ) . '-' . $this->name;
                if ( $thumbExt != $this->extension ) {
                        $thumbName .= ".$thumbExt";
                }
                return $thumbName;
        }

        /**
         * Create a thumbnail of the image having the specified width/height.
         * The thumbnail will not be created if the width is larger than the
         * image's width. Let the browser do the scaling in this case.
         * The thumbnail is stored on disk and is only computed if the thumbnail
         * file does not exist OR if it is older than the image.
         * Returns the URL.
         *
         * Keeps aspect ratio of original image. If both width and height are
         * specified, the generated image will be no bigger than width x height,
         * and will also have correct aspect ratio.
         *
         * @param integer $width        maximum width of the generated thumbnail
         * @param integer $height       maximum height of the image (optional)
         * @public
         */
        function createThumb( $width, $height = -1 ) {
                $params = array( 'width' => $width );
                if ( $height != -1 ) {
                        $params['height'] = $height;
                }
                $thumb = $this->transform( $params );
                if( is_null( $thumb ) || $thumb->isError() ) return '';
                return $thumb->getUrl();
        }

        /**
         * As createThumb, but returns a ThumbnailImage object. This can
         * provide access to the actual file, the real size of the thumb,
         * and can produce a convenient <img> tag for you.
         *
         * For non-image formats, this may return a filetype-specific icon.
         *
         * @param integer $width        maximum width of the generated thumbnail
         * @param integer $height       maximum height of the image (optional)
         * @param boolean $render       True to render the thumbnail if it doesn't exist,
         *                              false to just return the URL
         *
         * @return ThumbnailImage or null on failure
         * @public
         *
         * @deprecated use transform()
         */
        function getThumbnail( $width, $height=-1, $render = true ) {
                $params = array( 'width' => $width );
                if ( $height != -1 ) {
                        $params['height'] = $height;
                }
                $flags = $render ? self::RENDER_NOW : 0;
                return $this->transform( $params, $flags );
        }
        
        /**
         * Transform a media file
         *
         * @param array $params An associative array of handler-specific parameters. Typical 
         *                      keys are width, height and page.
         * @param integer $flags A bitfield, may contain self::RENDER_NOW to force rendering
         * @return MediaTransformOutput
         */
        function transform( $params, $flags = 0 ) {
                global $wgGenerateThumbnailOnParse, $wgUseSquid, $wgIgnoreImageErrors;

                wfProfileIn( __METHOD__ );
                do {
                        $handler = $this->getHandler();
                        if ( !$handler || !$handler->canRender() ) {
                                // not a bitmap or renderable image, don't try.
                                $thumb = $this->iconThumb();
                                break;
                        }

                        $script = $this->getTransformScript();
                        if ( $script && !($flags & self::RENDER_NOW) ) {
                                // Use a script to transform on client request
                                $thumb = $handler->getScriptedTransform( $this, $script, $params );
                                break;
                        }

                        $normalisedParams = $params;
                        $handler->normaliseParams( $this, $normalisedParams );
                        list( $thumbExt, $thumbMime ) = self::getThumbType( $this->extension, $this->mime );
                        $thumbName = $this->thumbName( $normalisedParams );     
                        $thumbPath = wfImageThumbDir( $this->name, $this->fromSharedDirectory ) .  "/$thumbName";
                        $thumbUrl = $this->thumbUrlFromName( $thumbName );


                        if ( !$wgGenerateThumbnailOnParse && !($flags & self::RENDER_NOW ) ) {
                                $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
                                break;
                        }
                        
                        wfDebug( "Doing stat for $thumbPath\n" );
                        $this->migrateThumbFile( $thumbName );
                        if ( file_exists( $thumbPath ) ) {
                                $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
                                break;
                        }

                        $thumb = $handler->doTransform( $this, $thumbPath, $thumbUrl, $params );

                        // Ignore errors if requested
                        if ( !$thumb ) {
                                $thumb = null;
                        } elseif ( $thumb->isError() ) {
                                $this->lastError = $thumb->toText();
                                if ( $wgIgnoreImageErrors && !($flags & self::RENDER_NOW) ) {
                                        $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
                                }
                        }
                        
                        if ( $wgUseSquid ) {
                                wfPurgeSquidServers( array( $thumbUrl ) );
                        }
                } while (false);

                wfProfileOut( __METHOD__ );
                return $thumb;
        }

        /**
         * Fix thumbnail files from 1.4 or before, with extreme prejudice
         */
        function migrateThumbFile( $thumbName ) {
                $thumbDir = wfImageThumbDir( $this->name, $this->fromSharedDirectory );
                $thumbPath = "$thumbDir/$thumbName";
                if ( is_dir( $thumbPath ) ) {
                        // Directory where file should be
                        // This happened occasionally due to broken migration code in 1.5
                        // Rename to broken-*
                        global $wgUploadDirectory;
                        for ( $i = 0; $i < 100 ; $i++ ) {
                                $broken = "$wgUploadDirectory/broken-$i-$thumbName";
                                if ( !file_exists( $broken ) ) {
                                        rename( $thumbPath, $broken );
                                        break;
                                }
                        }
                        // Doesn't exist anymore
                        clearstatcache();
                }
                if ( is_file( $thumbDir ) ) {
                        // File where directory should be
                        unlink( $thumbDir );
                        // Doesn't exist anymore
                        clearstatcache();
                }
        }

        /**
         * Get a MediaHandler instance for this image
         */
        function getHandler() {
                return MediaHandler::getHandler( $this->getMimeType() );
        }

        /**
         * Get a ThumbnailImage representing a file type icon
         * @return ThumbnailImage
         */
        function iconThumb() {
                global $wgStylePath, $wgStyleDirectory;

                $try = array( 'fileicon-' . $this->extension . '.png', 'fileicon.png' );
                foreach( $try as $icon ) {
                        $path = '/common/images/icons/' . $icon;
                        $filepath = $wgStyleDirectory . $path;
                        if( file_exists( $filepath ) ) {
                                return new ThumbnailImage( $wgStylePath . $path, 120, 120 );
                        }
                }
                return null;
        }

        /**
         * Get last thumbnailing error.
         * Largely obsolete.
         */
        function getLastError() {
                return $this->lastError;
        }

        /**
         * Get all thumbnail names previously generated for this image
         */
        function getThumbnails( $shared = false ) {
                if ( Image::isHashed( $shared ) ) {
                        $this->load();
                        $files = array();
                        $dir = wfImageThumbDir( $this->name, $shared );

                        if ( is_dir( $dir ) ) {
                                $handle = opendir( $dir );

                                if ( $handle ) {
                                        while ( false !== ( $file = readdir($handle) ) ) {
                                                if ( $file{0} != '.' ) {
                                                        $files[] = $file;
                                                }
                                        }
                                        closedir( $handle );
                                }
                        }
                } else {
                        $files = array();
                }

                return $files;
        }

        /**
         * Refresh metadata in memcached, but don't touch thumbnails or squid
         */
        function purgeMetadataCache() {
                clearstatcache();
                $this->loadFromFile();
                $this->saveToCache();
        }

        /**
         * Delete all previously generated thumbnails, refresh metadata in memcached and purge the squid
         */
        function purgeCache( $archiveFiles = array(), $shared = false ) {
                global $wgUseSquid;

                // Refresh metadata cache
                $this->purgeMetadataCache();

                // Delete thumbnails
                $files = $this->getThumbnails( $shared );
                $dir = wfImageThumbDir( $this->name, $shared );
                $urls = array();
                foreach ( $files as $file ) {
                        # Check that the base image name is part of the thumb name
                        # This is a basic sanity check to avoid erasing unrelated directories
                        if ( strpos( $file, $this->name ) !== false ) {
                                $url = $this->thumbUrlFromName( $file );
                                $urls[] = $url;
                                @unlink( "$dir/$file" );
                        }
                }

                // Purge the squid
                if ( $wgUseSquid ) {
                        $urls[] = $this->getURL();
                        foreach ( $archiveFiles as $file ) {
                                $urls[] = wfImageArchiveUrl( $file );
                        }
                        wfPurgeSquidServers( $urls );
                }
        }

        /**
         * Purge the image description page, but don't go after
         * pages using the image. Use when modifying file history
         * but not the current data.
         */
        function purgeDescription() {
                $page = Title::makeTitle( NS_IMAGE, $this->name );
                $page->invalidateCache();
                $page->purgeSquid();
        }

        /**
         * Purge metadata and all affected pages when the image is created,
         * deleted, or majorly updated. A set of additional URLs may be
         * passed to purge, such as specific image files which have changed.
         * @param $urlArray array
         */
        function purgeEverything( $urlArr=array() ) {
                // Delete thumbnails and refresh image metadata cache
                $this->purgeCache();
                $this->purgeDescription();

                // Purge cache of all pages using this image
                $update = new HTMLCacheUpdate( $this->getTitle(), 'imagelinks' );
                $update->doUpdate();
        }

        /**
         * Return the image history of this image, line by line.
         * starts with current version, then old versions.
         * uses $this->historyLine to check which line to return:
         *  0      return line for current version
         *  1      query for old versions, return first one
         *  2, ... return next old version from above query
         *
         * @public
         */
        function nextHistoryLine() {
                $dbr = wfGetDB( DB_SLAVE );

                if ( $this->historyLine == 0 ) {// called for the first time, return line from cur
                        $this->historyRes = $dbr->select( 'image',
                                array(
                                        'img_size',
                                        'img_description',
                                        'img_user','img_user_text',
                                        'img_timestamp',
                                        'img_width',
                                        'img_height',
                                        "'' AS oi_archive_name"
                                ),
                                array( 'img_name' => $this->title->getDBkey() ),
                                __METHOD__
                        );
                        if ( 0 == $dbr->numRows( $this->historyRes ) ) {
                                return FALSE;
                        }
                } else if ( $this->historyLine == 1 ) {
                        $this->historyRes = $dbr->select( 'oldimage',
                                array(
                                        'oi_size AS img_size',
                                        'oi_description AS img_description',
                                        'oi_user AS img_user',
                                        'oi_user_text AS img_user_text',
                                        'oi_timestamp AS img_timestamp',
                                        'oi_width as img_width',
                                        'oi_height as img_height',
                                        'oi_archive_name'
                                ),
                                array( 'oi_name' => $this->title->getDBkey() ),
                                __METHOD__,
                                array( 'ORDER BY' => 'oi_timestamp DESC' )
                        );
                }
                $this->historyLine ++;

                return $dbr->fetchObject( $this->historyRes );
        }

        /**
         * Reset the history pointer to the first element of the history
         * @public
         */
        function resetHistory() {
                $this->historyLine = 0;
        }

        /**
        * Return the full filesystem path to the file. Note that this does
        * not mean that a file actually exists under that location.
        *
        * This path depends on whether directory hashing is active or not,
        * i.e. whether the images are all found in the same directory,
        * or in hashed paths like /images/3/3c.
        *
        * @public
        * @param boolean $fromSharedDirectory Return the path to the file
        *   in a shared repository (see $wgUseSharedRepository and related
        *   options in DefaultSettings.php) instead of a local one.
        *
        */
        function getFullPath( $fromSharedRepository = false ) {
                global $wgUploadDirectory, $wgSharedUploadDirectory;

                $dir      = $fromSharedRepository ? $wgSharedUploadDirectory :
                                                    $wgUploadDirectory;

                // $wgSharedUploadDirectory may be false, if thumb.php is used
                if ( $dir ) {
                        $fullpath = $dir . wfGetHashPath($this->name, $fromSharedRepository) . $this->name;
                } else {
                        $fullpath = false;
                }

                return $fullpath;
        }

        /**
         * @return bool
         */
        public static function isHashed( $shared ) {
                global $wgHashedUploadDirectory, $wgHashedSharedUploadDirectory;
                return $shared ? $wgHashedSharedUploadDirectory : $wgHashedUploadDirectory;
        }

        /**
         * Record an image upload in the upload log and the image table
         */
        function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '', $watch = false ) {
                global $wgUser, $wgUseCopyrightUpload;

                $dbw = wfGetDB( DB_MASTER );

                // Delete thumbnails and refresh the metadata cache
                $this->purgeCache();

                // Fail now if the image isn't there
                if ( !$this->fileExists || $this->fromSharedDirectory ) {
                        wfDebug( "Image::recordUpload: File ".$this->imagePath." went missing!\n" );
                        return false;
                }

                if ( $wgUseCopyrightUpload ) {
                        if ( $license != '' ) {
                                $licensetxt = '== ' . wfMsgForContent( 'license' ) . " ==\n" . '{{' . $license . '}}' . "\n";
                        }
                        $textdesc = '== ' . wfMsg ( 'filedesc' ) . " ==\n" . $desc . "\n" .
                          '== ' . wfMsgForContent ( 'filestatus' ) . " ==\n" . $copyStatus . "\n" .
                          "$licensetxt" .
                          '== ' . wfMsgForContent ( 'filesource' ) . " ==\n" . $source ;
                } else {
                        if ( $license != '' ) {
                                $filedesc = $desc == '' ? '' : '== ' . wfMsg ( 'filedesc' ) . " ==\n" . $desc . "\n";
                                 $textdesc = $filedesc .
                                         '== ' . wfMsgForContent ( 'license' ) . " ==\n" . '{{' . $license . '}}' . "\n";
                        } else {
                                $textdesc = $desc;
                        }
                }

                $now = $dbw->timestamp();

                #split mime type
                if (strpos($this->mime,'/')!==false) {
                        list($major,$minor)= explode('/',$this->mime,2);
                }
                else {
                        $major= $this->mime;
                        $minor= "unknown";
                }

                # Test to see if the row exists using INSERT IGNORE
                # This avoids race conditions by locking the row until the commit, and also
                # doesn't deadlock. SELECT FOR UPDATE causes a deadlock for every race condition.
                $dbw->insert( 'image',
                        array(
                                'img_name' => $this->name,
                                'img_size'=> $this->size,
                                'img_width' => intval( $this->width ),
                                'img_height' => intval( $this->height ),
                                'img_bits' => $this->bits,
                                'img_media_type' => $this->type,
                                'img_major_mime' => $major,
                                'img_minor_mime' => $minor,
                                'img_timestamp' => $now,
                                'img_description' => $desc,
                                'img_user' => $wgUser->getID(),
                                'img_user_text' => $wgUser->getName(),
                                'img_metadata' => $this->metadata,
                        ),
                        __METHOD__,
                        'IGNORE'
                );

                if( $dbw->affectedRows() == 0 ) {
                        # Collision, this is an update of an image
                        # Insert previous contents into oldimage
                        $dbw->insertSelect( 'oldimage', 'image',
                                array(
                                        'oi_name' => 'img_name',
                                        'oi_archive_name' => $dbw->addQuotes( $oldver ),
                                        'oi_size' => 'img_size',
                                        'oi_width' => 'img_width',
                                        'oi_height' => 'img_height',
                                        'oi_bits' => 'img_bits',
                                        'oi_timestamp' => 'img_timestamp',
                                        'oi_description' => 'img_description',
                                        'oi_user' => 'img_user',
                                        'oi_user_text' => 'img_user_text',
                                ), array( 'img_name' => $this->name ), __METHOD__
                        );

                        # Update the current image row
                        $dbw->update( 'image',
                                array( /* SET */
                                        'img_size' => $this->size,
                                        'img_width' => intval( $this->width ),
                                        'img_height' => intval( $this->height ),
                                        'img_bits' => $this->bits,
                                        'img_media_type' => $this->type,
                                        'img_major_mime' => $major,
                                        'img_minor_mime' => $minor,
                                        'img_timestamp' => $now,
                                        'img_description' => $desc,
                                        'img_user' => $wgUser->getID(),
                                        'img_user_text' => $wgUser->getName(),
                                        'img_metadata' => $this->metadata,
                                ), array( /* WHERE */
                                        'img_name' => $this->name
                                ), __METHOD__
                        );
                } else {
                        # This is a new image
                        # Update the image count
                        $site_stats = $dbw->tableName( 'site_stats' );
                        $dbw->query( "UPDATE $site_stats SET ss_images=ss_images+1", __METHOD__ );
                }

                $descTitle = $this->getTitle();
                $article = new Article( $descTitle );
                $minor = false;
                $watch = $watch || $wgUser->isWatched( $descTitle );
                $suppressRC = true; // There's already a log entry, so don't double the RC load

                if( $descTitle->exists() ) {
                        // TODO: insert a null revision into the page history for this update.
                        if( $watch ) {
                                $wgUser->addWatch( $descTitle );
                        }

                        # Invalidate the cache for the description page
                        $descTitle->invalidateCache();
                        $descTitle->purgeSquid();
                } else {
                        // New image; create the description page.
                        $article->insertNewArticle( $textdesc, $desc, $minor, $watch, $suppressRC );
                }

                # Hooks, hooks, the magic of hooks...
                wfRunHooks( 'FileUpload', array( $this ) );

                # Add the log entry
                $log = new LogPage( 'upload' );
                $log->addEntry( 'upload', $descTitle, $desc );

                # Commit the transaction now, in case something goes wrong later
                # The most important thing is that images don't get lost, especially archives
                $dbw->immediateCommit();

                # Invalidate cache for all pages using this image
                $update = new HTMLCacheUpdate( $this->getTitle(), 'imagelinks' );
                $update->doUpdate();

                return true;
        }

        /**
         * Get an array of Title objects which are articles which use this image
         * Also adds their IDs to the link cache
         *
         * This is mostly copied from Title::getLinksTo()
         *
         * @deprecated Use HTMLCacheUpdate, this function uses too much memory
         */
        function getLinksTo( $options = '' ) {
                wfProfileIn( __METHOD__ );

                if ( $options ) {
                        $db = wfGetDB( DB_MASTER );
                } else {
                        $db = wfGetDB( DB_SLAVE );
                }
                $linkCache =& LinkCache::singleton();

                list( $page, $imagelinks ) = $db->tableNamesN( 'page', 'imagelinks' );
                $encName = $db->addQuotes( $this->name );
                $sql = "SELECT page_namespace,page_title,page_id FROM $page,$imagelinks WHERE page_id=il_from AND il_to=$encName $options";
                $res = $db->query( $sql, __METHOD__ );

                $retVal = array();
                if ( $db->numRows( $res ) ) {
                        while ( $row = $db->fetchObject( $res ) ) {
                                if ( $titleObj = Title::makeTitle( $row->page_namespace, $row->page_title ) ) {
                                        $linkCache->addGoodLinkObj( $row->page_id, $titleObj );
                                        $retVal[] = $titleObj;
                                }
                        }
                }
                $db->freeResult( $res );
                wfProfileOut( __METHOD__ );
                return $retVal;
        }

        function getExifData() {
                $handler = $this->getHandler();
                if ( !$handler || $handler->getMetadataType( $this ) != 'exif' ) {
                        return array();
                }
                if ( !$this->metadata ) {
                        return array();
                }
                $exif = unserialize( $this->metadata );
                if ( !$exif ) {
                        return array();
                }
                unset( $exif['MEDIAWIKI_EXIF_VERSION'] );
                $format = new FormatExif( $exif );

                return $format->getFormattedData();
        }

        /**
         * Returns true if the image does not come from the shared
         * image repository.
         *
         * @return bool
         */
        function isLocal() {
                return !$this->fromSharedDirectory;
        }

        /**
         * Was this image ever deleted from the wiki?
         *
         * @return bool
         */
        function wasDeleted() {
                $title = Title::makeTitle( NS_IMAGE, $this->name );
                return ( $title->isDeleted() > 0 );
        }

        /**
         * Delete all versions of the image.
         *
         * Moves the files into an archive directory (or deletes them)
         * and removes the database rows.
         *
         * Cache purging is done; logging is caller's responsibility.
         *
         * @param $reason
         * @return true on success, false on some kind of failure
         */
        function delete( $reason, $suppress=false ) {
                $transaction = new FSTransaction();
                $urlArr = array( $this->getURL() );

                if( !FileStore::lock() ) {
                        wfDebug( __METHOD__.": failed to acquire file store lock, aborting\n" );
                        return false;
                }

                try {
                        $dbw = wfGetDB( DB_MASTER );
                        $dbw->begin();

                        // Delete old versions
                        $result = $dbw->select( 'oldimage',
                                array( 'oi_archive_name' ),
                                array( 'oi_name' => $this->name ) );

                        while( $row = $dbw->fetchObject( $result ) ) {
                                $oldName = $row->oi_archive_name;

                                $transaction->add( $this->prepareDeleteOld( $oldName, $reason, $suppress ) );

                                // We'll need to purge this URL from caches...
                                $urlArr[] = wfImageArchiveUrl( $oldName );
                        }
                        $dbw->freeResult( $result );

                        // And the current version...
                        $transaction->add( $this->prepareDeleteCurrent( $reason, $suppress ) );

                        $dbw->immediateCommit();
                } catch( MWException $e ) {
                        wfDebug( __METHOD__.": db error, rolling back file transactions\n" );
                        $transaction->rollback();
                        FileStore::unlock();
                        throw $e;
                }

                wfDebug( __METHOD__.": deleted db items, applying file transactions\n" );
                $transaction->commit();
                FileStore::unlock();


                // Update site_stats
                $site_stats = $dbw->tableName( 'site_stats' );
                $dbw->query( "UPDATE $site_stats SET ss_images=ss_images-1", __METHOD__ );

                $this->purgeEverything( $urlArr );

                return true;
        }


        /**
         * Delete an old version of the image.
         *
         * Moves the file into an archive directory (or deletes it)
         * and removes the database row.
         *
         * Cache purging is done; logging is caller's responsibility.
         *
         * @param $reason
         * @throws MWException or FSException on database or filestore failure
         * @return true on success, false on some kind of failure
         */
        function deleteOld( $archiveName, $reason, $suppress=false ) {
                $transaction = new FSTransaction();
                $urlArr = array();

                if( !FileStore::lock() ) {
                        wfDebug( __METHOD__.": failed to acquire file store lock, aborting\n" );
                        return false;
                }

                $transaction = new FSTransaction();
                try {
                        $dbw = wfGetDB( DB_MASTER );
                        $dbw->begin();
                        $transaction->add( $this->prepareDeleteOld( $archiveName, $reason, $suppress ) );
                        $dbw->immediateCommit();
                } catch( MWException $e ) {
                        wfDebug( __METHOD__.": db error, rolling back file transaction\n" );
                        $transaction->rollback();
                        FileStore::unlock();
                        throw $e;
                }

                wfDebug( __METHOD__.": deleted db items, applying file transaction\n" );
                $transaction->commit();
                FileStore::unlock();

                $this->purgeDescription();

                // Squid purging
                global $wgUseSquid;
                if ( $wgUseSquid ) {
                        $urlArr = array(
                                wfImageArchiveUrl( $archiveName ),
                        );
                        wfPurgeSquidServers( $urlArr );
                }
                return true;
        }

        /**
         * Delete the current version of a file.
         * May throw a database error.
         * @return true on success, false on failure
         */
        private function prepareDeleteCurrent( $reason, $suppress=false ) {
                return $this->prepareDeleteVersion(
                        $this->getFullPath(),
                        $reason,
                        'image',
                        array(
                                'fa_name'         => 'img_name',
                                'fa_archive_name' => 'NULL',
                                'fa_size'         => 'img_size',
                                'fa_width'        => 'img_width',
                                'fa_height'       => 'img_height',
                                'fa_metadata'     => 'img_metadata',
                                'fa_bits'         => 'img_bits',
                                'fa_media_type'   => 'img_media_type',
                                'fa_major_mime'   => 'img_major_mime',
                                'fa_minor_mime'   => 'img_minor_mime',
                                'fa_description'  => 'img_description',
                                'fa_user'         => 'img_user',
                                'fa_user_text'    => 'img_user_text',
                                'fa_timestamp'    => 'img_timestamp' ),
                        array( 'img_name' => $this->name ),
                        $suppress,
                        __METHOD__ );
        }

        /**
         * Delete a given older version of a file.
         * May throw a database error.
         * @return true on success, false on failure
         */
        private function prepareDeleteOld( $archiveName, $reason, $suppress=false ) {
                $oldpath = wfImageArchiveDir( $this->name ) .
                        DIRECTORY_SEPARATOR . $archiveName;
                return $this->prepareDeleteVersion(
                        $oldpath,
                        $reason,
                        'oldimage',
                        array(
                                'fa_name'         => 'oi_name',
                                'fa_archive_name' => 'oi_archive_name',
                                'fa_size'         => 'oi_size',
                                'fa_width'        => 'oi_width',
                                'fa_height'       => 'oi_height',
                                'fa_metadata'     => 'NULL',
                                'fa_bits'         => 'oi_bits',
                                'fa_media_type'   => 'NULL',
                                'fa_major_mime'   => 'NULL',
                                'fa_minor_mime'   => 'NULL',
                                'fa_description'  => 'oi_description',
                                'fa_user'         => 'oi_user',
                                'fa_user_text'    => 'oi_user_text',
                                'fa_timestamp'    => 'oi_timestamp' ),
                        array(
                                'oi_name' => $this->name,
                                'oi_archive_name' => $archiveName ),
                        $suppress,
                        __METHOD__ );
        }

        /**
         * Do the dirty work of backing up an image row and its file
         * (if $wgSaveDeletedFiles is on) and removing the originals.
         *
         * Must be run while the file store is locked and a database
         * transaction is open to avoid race conditions.
         *
         * @return FSTransaction
         */
        private function prepareDeleteVersion( $path, $reason, $table, $fieldMap, $where, $suppress=false, $fname ) {
                global $wgUser, $wgSaveDeletedFiles;

                // Dupe the file into the file store
                if( file_exists( $path ) ) {
                        if( $wgSaveDeletedFiles ) {
                                $group = 'deleted';

                                $store = FileStore::get( $group );
                                $key = FileStore::calculateKey( $path, $this->extension );
                                $transaction = $store->insert( $key, $path,
                                        FileStore::DELETE_ORIGINAL );
                        } else {
                                $group = null;
                                $key = null;
                                $transaction = FileStore::deleteFile( $path );
                        }
                } else {
                        wfDebug( __METHOD__." deleting already-missing '$path'; moving on to database\n" );
                        $group = null;
                        $key = null;
                        $transaction = new FSTransaction(); // empty
                }

                if( $transaction === false ) {
                        // Fail to restore?
                        wfDebug( __METHOD__.": import to file store failed, aborting\n" );
                        throw new MWException( "Could not archive and delete file $path" );
                        return false;
                }
                
                // Bitfields to further supress the image content
                // Note that currently, live images are stored elsewhere
                // and cannot be partially deleted
                $bitfield = 0;
                if ( $suppress ) {
                        $bitfield |= self::DELETED_FILE;
                        $bitfield |= self::DELETED_COMMENT;
                        $bitfield |= self::DELETED_USER;
                        $bitfield |= self::DELETED_RESTRICTED;
                }

                $dbw = wfGetDB( DB_MASTER );
                $storageMap = array(
                        'fa_storage_group' => $dbw->addQuotes( $group ),
                        'fa_storage_key'   => $dbw->addQuotes( $key ),

                        'fa_deleted_user'      => $dbw->addQuotes( $wgUser->getId() ),
                        'fa_deleted_timestamp' => $dbw->timestamp(),
                        'fa_deleted_reason'    => $dbw->addQuotes( $reason ),
                        'fa_deleted'               => $bitfield);
                $allFields = array_merge( $storageMap, $fieldMap );

                try {
                        if( $wgSaveDeletedFiles ) {
                                $dbw->insertSelect( 'filearchive', $table, $allFields, $where, $fname );
                        }
                        $dbw->delete( $table, $where, $fname );
                } catch( DBQueryError $e ) {
                        // Something went horribly wrong!
                        // Leave the file as it was...
                        wfDebug( __METHOD__.": database error, rolling back file transaction\n" );
                        $transaction->rollback();
                        throw $e;
                }

                return $transaction;
        }

        /**
         * Restore all or specified deleted revisions to the given file.
         * Permissions and logging are left to the caller.
         *
         * May throw database exceptions on error.
         *
         * @param $versions set of record ids of deleted items to restore,
         *                    or empty to restore all revisions.
         * @return the number of file revisions restored if successful,
         *         or false on failure
         */
        function restore( $versions=array(), $Unsuppress=false ) {
                global $wgUser;
        
                if( !FileStore::lock() ) {
                        wfDebug( __METHOD__." could not acquire filestore lock\n" );
                        return false;
                }

                $transaction = new FSTransaction();
                try {
                        $dbw = wfGetDB( DB_MASTER );
                        $dbw->begin();

                        // Re-confirm whether this image presently exists;
                        // if no we'll need to create an image record for the
                        // first item we restore.
                        $exists = $dbw->selectField( 'image', '1',
                                array( 'img_name' => $this->name ),
                                __METHOD__ );

                        // Fetch all or selected archived revisions for the file,
                        // sorted from the most recent to the oldest.
                        $conditions = array( 'fa_name' => $this->name );
                        if( $versions ) {
                                $conditions['fa_id'] = $versions;
                        }

                        $result = $dbw->select( 'filearchive', '*',
                                $conditions,
                                __METHOD__,
                                array( 'ORDER BY' => 'fa_timestamp DESC' ) );

                        if( $dbw->numRows( $result ) < count( $versions ) ) {
                                // There's some kind of conflict or confusion;
                                // we can't restore everything we were asked to.
                                wfDebug( __METHOD__.": couldn't find requested items\n" );
                                $dbw->rollback();
                                FileStore::unlock();
                                return false;
                        }

                        if( $dbw->numRows( $result ) == 0 ) {
                                // Nothing to do.
                                wfDebug( __METHOD__.": nothing to do\n" );
                                $dbw->rollback();
                                FileStore::unlock();
                                return true;
                        }

                        $revisions = 0;
                        while( $row = $dbw->fetchObject( $result ) ) {
                                if ( $Unsuppress ) {
                                // Currently, fa_deleted flags fall off upon restore, lets be careful about this
                                } else if ( ($row->fa_deleted & Revision::DELETED_RESTRICTED) && !$wgUser->isAllowed('hiderevision') ) {
                                // Skip restoring file revisions that the user cannot restore
                                        continue;
                                }
                                $revisions++;
                                $store = FileStore::get( $row->fa_storage_group );
                                if( !$store ) {
                                        wfDebug( __METHOD__.": skipping row with no file.\n" );
                                        continue;
                                }

                                if( $revisions == 1 && !$exists ) {
                                        $destDir = wfImageDir( $row->fa_name );
                                        if ( !is_dir( $destDir ) ) {
                                                wfMkdirParents( $destDir );
                                        }
                                        $destPath = $destDir . DIRECTORY_SEPARATOR . $row->fa_name;

                                        // We may have to fill in data if this was originally
                                        // an archived file revision.
                                        if( is_null( $row->fa_metadata ) ) {
                                                $tempFile = $store->filePath( $row->fa_storage_key );

                                                $magic = MimeMagic::singleton();
                                                $mime = $magic->guessMimeType( $tempFile, true );
                                                $media_type = $magic->getMediaType( $tempFile, $mime );
                                                list( $major_mime, $minor_mime ) = self::splitMime( $mime );
                                                $handler = MediaHandler::getHandler( $mime );
                                                if ( $handler ) {
                                                        $metadata = $handler->getMetadata( $image, $tempFile );
                                                } else {
                                                        $metadata = '';
                                                }
                                        } else {
                                                $metadata   = $row->fa_metadata;
                                                $major_mime = $row->fa_major_mime;
                                                $minor_mime = $row->fa_minor_mime;
                                                $media_type = $row->fa_media_type;
                                        }

                                        $table = 'image';
                                        $fields = array(
                                                'img_name'        => $row->fa_name,
                                                'img_size'        => $row->fa_size,
                                                'img_width'       => $row->fa_width,
                                                'img_height'      => $row->fa_height,
                                                'img_metadata'    => $metadata,
                                                'img_bits'        => $row->fa_bits,
                                                'img_media_type'  => $media_type,
                                                'img_major_mime'  => $major_mime,
                                                'img_minor_mime'  => $minor_mime,
                                                'img_description' => $row->fa_description,
                                                'img_user'        => $row->fa_user,
                                                'img_user_text'   => $row->fa_user_text,
                                                'img_timestamp'   => $row->fa_timestamp );
                                } else {
                                        $archiveName = $row->fa_archive_name;
                                        if( $archiveName == '' ) {
                                                // This was originally a current version; we
                                                // have to devise a new archive name for it.
                                                // Format is <timestamp of archiving>!<name>
                                                $archiveName =
                                                        wfTimestamp( TS_MW, $row->fa_deleted_timestamp ) .
                                                        '!' . $row->fa_name;
                                        }
                                        $destDir = wfImageArchiveDir( $row->fa_name );
                                        if ( !is_dir( $destDir ) ) {
                                                wfMkdirParents( $destDir );
                                        }
                                        $destPath = $destDir . DIRECTORY_SEPARATOR . $archiveName;

                                        $table = 'oldimage';
                                        $fields = array(
                                                'oi_name'         => $row->fa_name,
                                                'oi_archive_name' => $archiveName,
                                                'oi_size'         => $row->fa_size,
                                                'oi_width'        => $row->fa_width,
                                                'oi_height'       => $row->fa_height,
                                                'oi_bits'         => $row->fa_bits,
                                                'oi_description'  => $row->fa_description,
                                                'oi_user'         => $row->fa_user,
                                                'oi_user_text'    => $row->fa_user_text,
                                                'oi_timestamp'    => $row->fa_timestamp );
                                }

                                $dbw->insert( $table, $fields, __METHOD__ );
                                // @todo this delete is not totally safe, potentially
                                $dbw->delete( 'filearchive',
                                        array( 'fa_id' => $row->fa_id ),
                                        __METHOD__ );

                                // Check if any other stored revisions use this file;
                                // if so, we shouldn't remove the file from the deletion
                                // archives so they will still work.
                                $useCount = $dbw->selectField( 'filearchive',
                                        'COUNT(*)',
                                        array(
                                                'fa_storage_group' => $row->fa_storage_group,
                                                'fa_storage_key'   => $row->fa_storage_key ),
                                        __METHOD__ );
                                if( $useCount == 0 ) {
                                        wfDebug( __METHOD__.": nothing else using {$row->fa_storage_key}, will deleting after\n" );
                                        $flags = FileStore::DELETE_ORIGINAL;
                                } else {
                                        $flags = 0;
                                }

                                $transaction->add( $store->export( $row->fa_storage_key,
                                        $destPath, $flags ) );
                        }

                        $dbw->immediateCommit();
                } catch( MWException $e ) {
                        wfDebug( __METHOD__." caught error, aborting\n" );
                        $transaction->rollback();
                        throw $e;
                }

                $transaction->commit();
                FileStore::unlock();

                if( $revisions > 0 ) {
                        if( !$exists ) {
                                wfDebug( __METHOD__." restored $revisions items, creating a new current\n" );

                                // Update site_stats
                                $site_stats = $dbw->tableName( 'site_stats' );
                                $dbw->query( "UPDATE $site_stats SET ss_images=ss_images+1", __METHOD__ );

                                $this->purgeEverything();
                        } else {
                                wfDebug( __METHOD__." restored $revisions as archived versions\n" );
                                $this->purgeDescription();
                        }
                }

                return $revisions;
        }

        /**
         * Returns 'true' if this image is a multipage document, e.g. a DJVU
         * document.
         *
         * @return Bool
         */
        function isMultipage() {
                $handler = $this->getHandler();
                return $handler && $handler->isMultiPage();
        }

        /**
         * Returns the number of pages of a multipage document, or NULL for
         * documents which aren't multipage documents
         */
        function pageCount() {
                $handler = $this->getHandler();
                if ( $handler && $handler->isMultiPage() ) {
                        return $handler->pageCount( $this );
                } else {
                        return null;
                }
        }

        static function getCommonsDB() {
                static $dbc;
                global $wgLoadBalancer, $wgSharedUploadDBname;
                if ( !isset( $dbc ) ) {
                        $i = $wgLoadBalancer->getGroupIndex( 'commons' );
                        $dbinfo = $wgLoadBalancer->mServers[$i];
                        $dbc = new Database( $dbinfo['host'], $dbinfo['user'], 
                                $dbinfo['password'], $wgSharedUploadDBname );
                }
                return $dbc;
        }

        /**
         * Calculate the height of a thumbnail using the source and destination width
         */
        static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
                // Exact integer multiply followed by division
                if ( $srcWidth == 0 ) {
                        return 0;
                } else {
                        return round( $srcHeight * $dstWidth / $srcWidth );
                }
        }

        /**
         * Get an image size array like that returned by getimagesize(), or false if it 
         * can't be determined.
         *
         * @param string $fileName The filename
         * @return array
         */
        function getImageSize( $fileName ) {
                $handler = $this->getHandler();
                return $handler->getImageSize( $this, $fileName );
        }

        /**
         * Get the thumbnail extension and MIME type for a given source MIME type
         * @return array thumbnail extension and MIME type
         */
        static function getThumbType( $ext, $mime ) {
                $handler = MediaHandler::getHandler( $mime );
                if ( $handler ) {
                        return $handler->getThumbType( $ext, $mime );
                } else {
                        return array( $ext, $mime );
                }
        }

} //class


/**
 * @addtogroup Media
 */
class ArchivedFile
{
        /**
         * Returns a file object from the filearchive table
         * In the future, all current and old image storage
         * may use FileStore. There will be a "old" storage 
         * for current and previous file revisions as well as
         * the "deleted" group for archived revisions
         * @param $title, the corresponding image page title
         * @param $id, the image id, a unique key
         * @param $key, optional storage key
         * @return ResultWrapper
         */
        function ArchivedFile( $title, $id=0, $key='' ) {
                if( !is_object( $title ) ) {
                        throw new MWException( 'Image constructor given bogus title.' );
                }
                $conds = ($id) ? "fa_id = $id" : "fa_storage_key = '$key'";
                if( $title->getNamespace() == NS_IMAGE ) {
                        $dbr = wfGetDB( DB_SLAVE );
                        $res = $dbr->select( 'filearchive',
                                array(
                                        'fa_id',
                                        'fa_name',
                                        'fa_storage_key',
                                        'fa_storage_group',
                                        'fa_size',
                                        'fa_bits',
                                        'fa_width',
                                        'fa_height',
                                        'fa_metadata',
                                        'fa_media_type',
                                        'fa_major_mime',
                                        'fa_minor_mime',
                                        'fa_description',
                                        'fa_user',
                                        'fa_user_text',
                                        'fa_timestamp',
                                        'fa_deleted' ),
                                array( 
                                        'fa_name' => $title->getDbKey(),
                                        $conds ),
                                __METHOD__,
                                array( 'ORDER BY' => 'fa_timestamp DESC' ) );
                                
                        if ( $dbr->numRows( $res ) == 0 ) {
                        // this revision does not exist?
                                return;
                        }
                        $ret = $dbr->resultObject( $res );
                        $row = $ret->fetchObject();
        
                        // initialize fields for filestore image object
                        $this->mId = intval($row->fa_id);
                        $this->mName = $row->fa_name;
                        $this->mGroup = $row->fa_storage_group;
                        $this->mKey = $row->fa_storage_key;
                        $this->mSize = $row->fa_size;
                        $this->mBits = $row->fa_bits;
                        $this->mWidth = $row->fa_width;
                        $this->mHeight = $row->fa_height;
                        $this->mMetaData = $row->fa_metadata;
                        $this->mMime = "$row->fa_major_mime/$row->fa_minor_mime";
                        $this->mType = $row->fa_media_type;
                        $this->mDescription = $row->fa_description;
                        $this->mUser = $row->fa_user;
                        $this->mUserText = $row->fa_user_text;
                        $this->mTimestamp = $row->fa_timestamp;
                        $this->mDeleted = $row->fa_deleted;             
                } else {
                        throw new MWException( 'This title does not correspond to an image page.' );
                        return;
                }
                return true;
        }

        /**
         * int $field one of DELETED_* bitfield constants
         * for file or revision rows
         * @return bool
         */
        function isDeleted( $field ) {
                return ($this->mDeleted & $field) == $field;
        }
        
        /**
         * Determine if the current user is allowed to view a particular
         * field of this FileStore image file, if it's marked as deleted.
         * @param int $field                                    
         * @return bool
         */
        function userCan( $field ) {
                if( isset($this->mDeleted) && ($this->mDeleted & $field) == $field ) {
                // images
                        global $wgUser;
                        $permission = ( $this->mDeleted & Revision::DELETED_RESTRICTED ) == Revision::DELETED_RESTRICTED
                                ? 'hiderevision'
                                : 'deleterevision';
                        wfDebug( "Checking for $permission due to $field match on $this->mDeleted\n" );
                        return $wgUser->isAllowed( $permission );
                } else {
                        return true;
                }
        }
}

/**
 * Aliases for backwards compatibility with 1.6
 */
define( 'MW_IMG_DELETED_FILE', Image::DELETED_FILE );
define( 'MW_IMG_DELETED_COMMENT', Image::DELETED_COMMENT );
define( 'MW_IMG_DELETED_USER', Image::DELETED_USER );
define( 'MW_IMG_DELETED_RESTRICTED', Image::DELETED_RESTRICTED );

?>