includes/filerepo/file/File.php

   1 <?php
   2 /**
   3  * @defgroup FileAbstraction File abstraction
   4  * @ingroup FileRepo
   5  *
   6  * Represents files in a repository.
   7  */
   8
   9 /**
  10  * Base code for files.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with this program; if not, write to the Free Software Foundation, Inc.,
  24  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  25  * http://www.gnu.org/copyleft/gpl.html
  26  *
  27  * @file
  28  * @ingroup FileAbstraction
  29  */
  30
  31 /**
  32  * Implements some public methods and some protected utility functions which
  33  * are required by multiple child classes. Contains stub functionality for
  34  * unimplemented public methods.
  35  *
  36  * Stub functions which should be overridden are marked with STUB. Some more
  37  * concrete functions are also typically overridden by child classes.
  38  *
  39  * Note that only the repo object knows what its file class is called. You should
  40  * never name a file class explictly outside of the repo class. Instead use the
  41  * repo's factory functions to generate file objects, for example:
  42  *
  43  * RepoGroup::singleton()->getLocalRepo()->newFile($title);
  44  *
  45  * The convenience functions wfLocalFile() and wfFindFile() should be sufficient
  46  * in most cases.
  47  *
  48  * @ingroup FileAbstraction
  49  */
  50 abstract class File {
  51         const DELETED_FILE = 1;
  52         const DELETED_COMMENT = 2;
  53         const DELETED_USER = 4;
  54         const DELETED_RESTRICTED = 8;
  55
  56         /** Force rendering in the current process */
  57         const RENDER_NOW   = 1;
  58         /**
  59          * Force rendering even if thumbnail already exist and using RENDER_NOW
  60          * I.e. you have to pass both flags: File::RENDER_NOW | File::RENDER_FORCE
  61          */
  62         const RENDER_FORCE = 2;
  63
  64         const DELETE_SOURCE = 1;
  65
  66         // Audience options for File::getDescription()
  67         const FOR_PUBLIC = 1;
  68         const FOR_THIS_USER = 2;
  69         const RAW = 3;
  70
  71         // Options for File::thumbName()
  72         const THUMB_FULL_NAME = 1;
  73
  74         /**
  75          * Some member variables can be lazy-initialised using __get(). The
  76          * initialisation function for these variables is always a function named
  77          * like getVar(), where Var is the variable name with upper-case first
  78          * letter.
  79          *
  80          * The following variables are initialised in this way in this base class:
  81          *    name, extension, handler, path, canRender, isSafeFile,
  82          *    transformScript, hashPath, pageCount, url
  83          *
  84          * Code within this class should generally use the accessor function
  85          * directly, since __get() isn't re-entrant and therefore causes bugs that
  86          * depend on initialisation order.
  87          */
  88
  89         /**
  90          * The following member variables are not lazy-initialised
  91          */
  92
  93         /**
  94          * @var FileRepo|bool
  95          */
  96         var $repo;
  97
  98         /**
  99          * @var Title
 100          */
 101         var $title;
 102
 103         var $lastError, $redirected, $redirectedTitle;
 104
 105         /**
 106          * @var FSFile|bool False if undefined
 107          */
 108         protected $fsFile;
 109
 110         /**
 111          * @var MediaHandler
 112          */
 113         protected $handler;
 114
 115         /**
 116          * @var string
 117          */
 118         protected $url, $extension, $name, $path, $hashPath, $pageCount, $transformScript;
 119
 120         protected $redirectTitle;
 121
 122         /**
 123          * @var bool
 124          */
 125         protected $canRender, $isSafeFile;
 126
 127         /**
 128          * @var string Required Repository class type
 129          */
 130         protected $repoClass = 'FileRepo';
 131
 132         /**
 133          * Call this constructor from child classes.
 134          *
 135          * Both $title and $repo are optional, though some functions
 136          * may return false or throw exceptions if they are not set.
 137          * Most subclasses will want to call assertRepoDefined() here.
 138          *
 139          * @param $title Title|string|bool
 140          * @param $repo FileRepo|bool
 141          */
 142         function __construct( $title, $repo ) {
 143                 if ( $title !== false ) { // subclasses may not use MW titles
 144                         $title = self::normalizeTitle( $title, 'exception' );
 145                 }
 146                 $this->title = $title;
 147                 $this->repo = $repo;
 148         }
 149
 150         /**
 151          * Given a string or Title object return either a
 152          * valid Title object with namespace NS_FILE or null
 153          *
 154          * @param $title Title|string
 155          * @param $exception string|bool Use 'exception' to throw an error on bad titles
 156          * @throws MWException
 157          * @return Title|null
 158          */
 159         static function normalizeTitle( $title, $exception = false ) {
 160                 $ret = $title;
 161                 if ( $ret instanceof Title ) {
 162                         # Normalize NS_MEDIA -> NS_FILE
 163                         if ( $ret->getNamespace() == NS_MEDIA ) {
 164                                 $ret = Title::makeTitleSafe( NS_FILE, $ret->getDBkey() );
 165                         # Sanity check the title namespace
 166                         } elseif ( $ret->getNamespace() !== NS_FILE ) {
 167                                 $ret = null;
 168                         }
 169                 } else {
 170                         # Convert strings to Title objects
 171                         $ret = Title::makeTitleSafe( NS_FILE, (string)$ret );
 172                 }
 173                 if ( !$ret && $exception !== false ) {
 174                         throw new MWException( "`$title` is not a valid file title." );
 175                 }
 176                 return $ret;
 177         }
 178
 179         function __get( $name ) {
 180                 $function = array( $this, 'get' . ucfirst( $name ) );
 181                 if ( !is_callable( $function ) ) {
 182                         return null;
 183                 } else {
 184                         $this->$name = call_user_func( $function );
 185                         return $this->$name;
 186                 }
 187         }
 188
 189         /**
 190          * Normalize a file extension to the common form, and ensure it's clean.
 191          * Extensions with non-alphanumeric characters will be discarded.
 192          *
 193          * @param $ext string (without the .)
 194          * @return string
 195          */
 196         static function normalizeExtension( $ext ) {
 197                 $lower = strtolower( $ext );
 198                 $squish = array(
 199                         'htm' => 'html',
 200                         'jpeg' => 'jpg',
 201                         'mpeg' => 'mpg',
 202                         'tiff' => 'tif',
 203                         'ogv' => 'ogg' );
 204                 if( isset( $squish[$lower] ) ) {
 205                         return $squish[$lower];
 206                 } elseif( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 207                         return $lower;
 208                 } else {
 209                         return '';
 210                 }
 211         }
 212
 213         /**
 214          * Checks if file extensions are compatible
 215          *
 216          * @param $old File Old file
 217          * @param $new string New name
 218          *
 219          * @return bool|null
 220          */
 221         static function checkExtensionCompatibility( File $old, $new ) {
 222                 $oldMime = $old->getMimeType();
 223                 $n = strrpos( $new, '.' );
 224                 $newExt = self::normalizeExtension( $n ? substr( $new, $n + 1 ) : '' );
 225                 $mimeMagic = MimeMagic::singleton();
 226                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 227         }
 228
 229         /**
 230          * Upgrade the database row if there is one
 231          * Called by ImagePage
 232          * STUB
 233          */
 234         function upgradeRow() {}
 235
 236         /**
 237          * Split an internet media type into its two components; if not
 238          * a two-part name, set the minor type to 'unknown'.
 239          *
 240          * @param string $mime "text/html" etc
 241          * @return array ("text", "html") etc
 242          */
 243         public static function splitMime( $mime ) {
 244                 if( strpos( $mime, '/' ) !== false ) {
 245                         return explode( '/', $mime, 2 );
 246                 } else {
 247                         return array( $mime, 'unknown' );
 248                 }
 249         }
 250
 251         /**
 252          * Callback for usort() to do file sorts by name
 253          *
 254          * @param $a File
 255          * @param $b File
 256          *
 257          * @return Integer: result of name comparison
 258          */
 259         public static function compare( File $a, File $b ) {
 260                 return strcmp( $a->getName(), $b->getName() );
 261         }
 262
 263         /**
 264          * Return the name of this file
 265          *
 266          * @return string
 267          */
 268         public function getName() {
 269                 if ( !isset( $this->name ) ) {
 270                         $this->assertRepoDefined();
 271                         $this->name = $this->repo->getNameFromTitle( $this->title );
 272                 }
 273                 return $this->name;
 274         }
 275
 276         /**
 277          * Get the file extension, e.g. "svg"
 278          *
 279          * @return string
 280          */
 281         function getExtension() {
 282                 if ( !isset( $this->extension ) ) {
 283                         $n = strrpos( $this->getName(), '.' );
 284                         $this->extension = self::normalizeExtension(
 285                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 286                 }
 287                 return $this->extension;
 288         }
 289
 290         /**
 291          * Return the associated title object
 292          *
 293          * @return Title
 294          */
 295         public function getTitle() {
 296                 return $this->title;
 297         }
 298
 299         /**
 300          * Return the title used to find this file
 301          *
 302          * @return Title
 303          */
 304         public function getOriginalTitle() {
 305                 if ( $this->redirected ) {
 306                         return $this->getRedirectedTitle();
 307                 }
 308                 return $this->title;
 309         }
 310
 311         /**
 312          * Return the URL of the file
 313          *
 314          * @return string
 315          */
 316         public function getUrl() {
 317                 if ( !isset( $this->url ) ) {
 318                         $this->assertRepoDefined();
 319                         $ext = $this->getExtension();
 320                         $this->url = $this->repo->getZoneUrl( 'public', $ext ) . '/' . $this->getUrlRel();
 321                 }
 322                 return $this->url;
 323         }
 324
 325         /**
 326          * Return a fully-qualified URL to the file.
 327          * Upload URL paths _may or may not_ be fully qualified, so
 328          * we check. Local paths are assumed to belong on $wgServer.
 329          *
 330          * @return String
 331          */
 332         public function getFullUrl() {
 333                 return wfExpandUrl( $this->getUrl(), PROTO_RELATIVE );
 334         }
 335
 336         /**
 337          * @return string
 338          */
 339         public function getCanonicalUrl() {
 340                 return wfExpandUrl( $this->getUrl(), PROTO_CANONICAL );
 341         }
 342
 343         /**
 344          * @return string
 345          */
 346         function getViewURL() {
 347                 if ( $this->mustRender() ) {
 348                         if ( $this->canRender() ) {
 349                                 return $this->createThumb( $this->getWidth() );
 350                         } else {
 351                                 wfDebug( __METHOD__.': supposed to render ' . $this->getName() .
 352                                         ' (' . $this->getMimeType() . "), but can't!\n" );
 353                                 return $this->getURL(); #hm... return NULL?
 354                         }
 355                 } else {
 356                         return $this->getURL();
 357                 }
 358         }
 359
 360         /**
 361          * Return the storage path to the file. Note that this does
 362          * not mean that a file actually exists under that location.
 363          *
 364          * This path depends on whether directory hashing is active or not,
 365          * i.e. whether the files are all found in the same directory,
 366          * or in hashed paths like /images/3/3c.
 367          *
 368          * Most callers don't check the return value, but ForeignAPIFile::getPath
 369          * returns false.
 370          *
 371          * @return string|bool ForeignAPIFile::getPath can return false
 372         */
 373         public function getPath() {
 374                 if ( !isset( $this->path ) ) {
 375                         $this->assertRepoDefined();
 376                         $this->path = $this->repo->getZonePath( 'public' ) . '/' . $this->getRel();
 377                 }
 378                 return $this->path;
 379         }
 380
 381         /**
 382          * Get an FS copy or original of this file and return the path.
 383          * Returns false on failure. Callers must not alter the file.
 384          * Temporary files are cleared automatically.
 385          *
 386          * @return string|bool False on failure
 387          */
 388         public function getLocalRefPath() {
 389                 $this->assertRepoDefined();
 390                 if ( !isset( $this->fsFile ) ) {
 391                         $this->fsFile = $this->repo->getLocalReference( $this->getPath() );
 392                         if ( !$this->fsFile ) {
 393                                 $this->fsFile = false; // null => false; cache negative hits
 394                         }
 395                 }
 396                 return ( $this->fsFile )
 397                         ? $this->fsFile->getPath()
 398                         : false;
 399         }
 400
 401         /**
 402          * Return the width of the image. Returns false if the width is unknown
 403          * or undefined.
 404          *
 405          * STUB
 406          * Overridden by LocalFile, UnregisteredLocalFile
 407          *
 408          * @param $page int
 409          *
 410          * @return number
 411          */
 412         public function getWidth( $page = 1 ) {
 413                 return false;
 414         }
 415
 416         /**
 417          * Return the height of the image. Returns false if the height is unknown
 418          * or undefined
 419          *
 420          * STUB
 421          * Overridden by LocalFile, UnregisteredLocalFile
 422          *
 423          * @param $page int
 424          *
 425          * @return bool|number False on failure
 426          */
 427         public function getHeight( $page = 1 ) {
 428                 return false;
 429         }
 430
 431         /**
 432          * Returns ID or name of user who uploaded the file
 433          * STUB
 434          *
 435          * @param $type string 'text' or 'id'
 436          *
 437          * @return string|int
 438          */
 439         public function getUser( $type = 'text' ) {
 440                 return null;
 441         }
 442
 443         /**
 444          * Get the duration of a media file in seconds
 445          *
 446          * @return number
 447          */
 448         public function getLength() {
 449                 $handler = $this->getHandler();
 450                 if ( $handler ) {
 451                         return $handler->getLength( $this );
 452                 } else {
 453                         return 0;
 454                 }
 455         }
 456
 457         /**
 458          * Return true if the file is vectorized
 459          *
 460          * @return bool
 461          */
 462         public function isVectorized() {
 463                 $handler = $this->getHandler();
 464                 if ( $handler ) {
 465                         return $handler->isVectorized( $this );
 466                 } else {
 467                         return false;
 468                 }
 469         }
 470
 471         /**
 472          * Will the thumbnail be animated if one would expect it to be.
 473          *
 474          * Currently used to add a warning to the image description page
 475          *
 476          * @return bool false if the main image is both animated
 477          *   and the thumbnail is not. In all other cases must return
 478          *   true. If image is not renderable whatsoever, should
 479          *   return true.
 480          */
 481         public function canAnimateThumbIfAppropriate() {
 482                 $handler = $this->getHandler();
 483                 if ( !$handler ) {
 484                         // We cannot handle image whatsoever, thus
 485                         // one would not expect it to be animated
 486                         // so true.
 487                         return true;
 488                 } else {
 489                         if ( $this->allowInlineDisplay()
 490                                 && $handler->isAnimatedImage( $this )
 491                                 && !$handler->canAnimateThumbnail( $this )
 492                         ) {
 493                                 // Image is animated, but thumbnail isn't.
 494                                 // This is unexpected to the user.
 495                                 return false;
 496                         } else {
 497                                 // Image is not animated, so one would
 498                                 // not expect thumb to be
 499                                 return true;
 500                         }
 501                 }
 502         }
 503
 504         /**
 505          * Get handler-specific metadata
 506          * Overridden by LocalFile, UnregisteredLocalFile
 507          * STUB
 508          * @return bool
 509          */
 510         public function getMetadata() {
 511                 return false;
 512         }
 513
 514         /**
 515         * get versioned metadata
 516         *
 517         * @param $metadata Mixed Array or String of (serialized) metadata
 518         * @param $version integer version number.
 519         * @return Array containing metadata, or what was passed to it on fail (unserializing if not array)
 520         */
 521         public function convertMetadataVersion($metadata, $version) {
 522                 $handler = $this->getHandler();
 523                 if ( !is_array( $metadata ) ) {
 524                         // Just to make the return type consistent
 525                         $metadata = unserialize( $metadata );
 526                 }
 527                 if ( $handler ) {
 528                         return $handler->convertMetadataVersion( $metadata, $version );
 529                 } else {
 530                         return $metadata;
 531                 }
 532         }
 533
 534         /**
 535          * Return the bit depth of the file
 536          * Overridden by LocalFile
 537          * STUB
 538          * @return int
 539          */
 540         public function getBitDepth() {
 541                 return 0;
 542         }
 543
 544         /**
 545          * Return the size of the image file, in bytes
 546          * Overridden by LocalFile, UnregisteredLocalFile
 547          * STUB
 548          * @return bool
 549          */
 550         public function getSize() {
 551                 return false;
 552         }
 553
 554         /**
 555          * Returns the mime type of the file.
 556          * Overridden by LocalFile, UnregisteredLocalFile
 557          * STUB
 558          *
 559          * @return string
 560          */
 561         function getMimeType() {
 562                 return 'unknown/unknown';
 563         }
 564
 565         /**
 566          * Return the type of the media in the file.
 567          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 568          * Overridden by LocalFile,
 569          * STUB
 570          * @return string
 571          */
 572         function getMediaType() {
 573                 return MEDIATYPE_UNKNOWN;
 574         }
 575
 576         /**
 577          * Checks if the output of transform() for this file is likely
 578          * to be valid. If this is false, various user elements will
 579          * display a placeholder instead.
 580          *
 581          * Currently, this checks if the file is an image format
 582          * that can be converted to a format
 583          * supported by all browsers (namely GIF, PNG and JPEG),
 584          * or if it is an SVG image and SVG conversion is enabled.
 585          *
 586          * @return bool
 587          */
 588         function canRender() {
 589                 if ( !isset( $this->canRender ) ) {
 590                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this );
 591                 }
 592                 return $this->canRender;
 593         }
 594
 595         /**
 596          * Accessor for __get()
 597          * @return bool
 598          */
 599         protected function getCanRender() {
 600                 return $this->canRender();
 601         }
 602
 603         /**
 604          * Return true if the file is of a type that can't be directly
 605          * rendered by typical browsers and needs to be re-rasterized.
 606          *
 607          * This returns true for everything but the bitmap types
 608          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 609          * also return true for any non-image formats.
 610          *
 611          * @return bool
 612          */
 613         function mustRender() {
 614                 return $this->getHandler() && $this->handler->mustRender( $this );
 615         }
 616
 617         /**
 618          * Alias for canRender()
 619          *
 620          * @return bool
 621          */
 622         function allowInlineDisplay() {
 623                 return $this->canRender();
 624         }
 625
 626         /**
 627          * Determines if this media file is in a format that is unlikely to
 628          * contain viruses or malicious content. It uses the global
 629          * $wgTrustedMediaFormats list to determine if the file is safe.
 630          *
 631          * This is used to show a warning on the description page of non-safe files.
 632          * It may also be used to disallow direct [[media:...]] links to such files.
 633          *
 634          * Note that this function will always return true if allowInlineDisplay()
 635          * or isTrustedFile() is true for this file.
 636          *
 637          * @return bool
 638          */
 639         function isSafeFile() {
 640                 if ( !isset( $this->isSafeFile ) ) {
 641                         $this->isSafeFile = $this->_getIsSafeFile();
 642                 }
 643                 return $this->isSafeFile;
 644         }
 645
 646         /**
 647          * Accessor for __get()
 648          *
 649          * @return bool
 650          */
 651         protected function getIsSafeFile() {
 652                 return $this->isSafeFile();
 653         }
 654
 655         /**
 656          * Uncached accessor
 657          *
 658          * @return bool
 659          */
 660         protected function _getIsSafeFile() {
 661                 global $wgTrustedMediaFormats;
 662
 663                 if ( $this->allowInlineDisplay() ) {
 664                         return true;
 665                 }
 666                 if ($this->isTrustedFile()) {
 667                         return true;
 668                 }
 669
 670                 $type = $this->getMediaType();
 671                 $mime = $this->getMimeType();
 672                 #wfDebug("LocalFile::isSafeFile: type= $type, mime= $mime\n");
 673
 674                 if ( !$type || $type === MEDIATYPE_UNKNOWN ) {
 675                         return false; #unknown type, not trusted
 676                 }
 677                 if ( in_array( $type, $wgTrustedMediaFormats ) ) {
 678                         return true;
 679                 }
 680
 681                 if ( $mime === "unknown/unknown" ) {
 682                         return false; #unknown type, not trusted
 683                 }
 684                 if ( in_array( $mime, $wgTrustedMediaFormats) ) {
 685                         return true;
 686                 }
 687
 688                 return false;
 689         }
 690
 691         /**
 692          * Returns true if the file is flagged as trusted. Files flagged that way
 693          * can be linked to directly, even if that is not allowed for this type of
 694          * file normally.
 695          *
 696          * This is a dummy function right now and always returns false. It could be
 697          * implemented to extract a flag from the database. The trusted flag could be
 698          * set on upload, if the user has sufficient privileges, to bypass script-
 699          * and html-filters. It may even be coupled with cryptographics signatures
 700          * or such.
 701          *
 702          * @return bool
 703          */
 704         function isTrustedFile() {
 705                 #this could be implemented to check a flag in the database,
 706                 #look for signatures, etc
 707                 return false;
 708         }
 709
 710         /**
 711          * Returns true if file exists in the repository.
 712          *
 713          * Overridden by LocalFile to avoid unnecessary stat calls.
 714          *
 715          * @return boolean Whether file exists in the repository.
 716          */
 717         public function exists() {
 718                 return $this->getPath() && $this->repo->fileExists( $this->path );
 719         }
 720
 721         /**
 722          * Returns true if file exists in the repository and can be included in a page.
 723          * It would be unsafe to include private images, making public thumbnails inadvertently
 724          *
 725          * @return boolean Whether file exists in the repository and is includable.
 726          */
 727         public function isVisible() {
 728                 return $this->exists();
 729         }
 730
 731         /**
 732          * @return string
 733          */
 734         function getTransformScript() {
 735                 if ( !isset( $this->transformScript ) ) {
 736                         $this->transformScript = false;
 737                         if ( $this->repo ) {
 738                                 $script = $this->repo->getThumbScriptUrl();
 739                                 if ( $script ) {
 740                                         $this->transformScript = "$script?f=" . urlencode( $this->getName() );
 741                                 }
 742                         }
 743                 }
 744                 return $this->transformScript;
 745         }
 746
 747         /**
 748          * Get a ThumbnailImage which is the same size as the source
 749          *
 750          * @param $handlerParams array
 751          *
 752          * @return string
 753          */
 754         function getUnscaledThumb( $handlerParams = array() ) {
 755                 $hp =& $handlerParams;
 756                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 757                 $width = $this->getWidth( $page );
 758                 if ( !$width ) {
 759                         return $this->iconThumb();
 760                 }
 761                 $hp['width'] = $width;
 762                 return $this->transform( $hp );
 763         }
 764
 765         /**
 766          * Return the file name of a thumbnail with the specified parameters.
 767          * Use File::THUMB_FULL_NAME to always get a name like "<params>-<source>".
 768          * Otherwise, the format may be "<params>-<source>" or "<params>-thumbnail.<ext>".
 769          *
 770          * @param $params Array: handler-specific parameters
 771          * @param $flags integer Bitfield that supports THUMB_* constants
 772          * @return string
 773          */
 774         public function thumbName( $params, $flags = 0 ) {
 775                 $name = ( $this->repo && !( $flags & self::THUMB_FULL_NAME ) )
 776                         ? $this->repo->nameForThumb( $this->getName() )
 777                         : $this->getName();
 778                 return $this->generateThumbName( $name, $params );
 779         }
 780
 781         /**
 782          * Generate a thumbnail file name from a name and specified parameters
 783          *
 784          * @param string $name
 785          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 786          *
 787          * @return string
 788          */
 789         public function generateThumbName( $name, $params ) {
 790                 if ( !$this->getHandler() ) {
 791                         return null;
 792                 }
 793                 $extension = $this->getExtension();
 794                 list( $thumbExt, $thumbMime ) = $this->handler->getThumbType(
 795                         $extension, $this->getMimeType(), $params );
 796                 $thumbName = $this->handler->makeParamString( $params ) . '-' . $name;
 797                 if ( $thumbExt != $extension ) {
 798                         $thumbName .= ".$thumbExt";
 799                 }
 800                 return $thumbName;
 801         }
 802
 803         /**
 804          * Create a thumbnail of the image having the specified width/height.
 805          * The thumbnail will not be created if the width is larger than the
 806          * image's width. Let the browser do the scaling in this case.
 807          * The thumbnail is stored on disk and is only computed if the thumbnail
 808          * file does not exist OR if it is older than the image.
 809          * Returns the URL.
 810          *
 811          * Keeps aspect ratio of original image. If both width and height are
 812          * specified, the generated image will be no bigger than width x height,
 813          * and will also have correct aspect ratio.
 814          *
 815          * @param $width Integer: maximum width of the generated thumbnail
 816          * @param $height Integer: maximum height of the image (optional)
 817          *
 818          * @return string
 819          */
 820         public function createThumb( $width, $height = -1 ) {
 821                 $params = array( 'width' => $width );
 822                 if ( $height != -1 ) {
 823                         $params['height'] = $height;
 824                 }
 825                 $thumb = $this->transform( $params );
 826                 if ( is_null( $thumb ) || $thumb->isError() ) {
 827                         return '';
 828                 }
 829                 return $thumb->getUrl();
 830         }
 831
 832         /**
 833          * Return either a MediaTransformError or placeholder thumbnail (if $wgIgnoreImageErrors)
 834          *
 835          * @param $thumbPath string Thumbnail storage path
 836          * @param $thumbUrl string Thumbnail URL
 837          * @param $params Array
 838          * @param $flags integer
 839          * @return MediaTransformOutput
 840          */
 841         protected function transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags ) {
 842                 global $wgIgnoreImageErrors;
 843
 844                 if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 845                         return $this->getHandler()->getTransform( $this, $thumbPath, $thumbUrl, $params );
 846                 } else {
 847                         return new MediaTransformError( 'thumbnail_error',
 848                                 $params['width'], 0, wfMessage( 'thumbnail-dest-create' )->text() );
 849                 }
 850         }
 851
 852         /**
 853          * Transform a media file
 854          *
 855          * @param $params Array: an associative array of handler-specific parameters.
 856          *                Typical keys are width, height and page.
 857          * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
 858          * @return MediaTransformOutput|bool False on failure
 859          */
 860         function transform( $params, $flags = 0 ) {
 861                 global $wgUseSquid, $wgIgnoreImageErrors, $wgThumbnailEpoch;
 862
 863                 wfProfileIn( __METHOD__ );
 864                 do {
 865                         if ( !$this->canRender() ) {
 866                                 $thumb = $this->iconThumb();
 867                                 break; // not a bitmap or renderable image, don't try
 868                         }
 869
 870                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
 871                         $descriptionUrl = $this->getDescriptionUrl();
 872                         if ( $descriptionUrl ) {
 873                                 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
 874                         }
 875
 876                         $handler = $this->getHandler();
 877                         $script = $this->getTransformScript();
 878                         if ( $script && !( $flags & self::RENDER_NOW ) ) {
 879                                 // Use a script to transform on client request, if possible
 880                                 $thumb = $handler->getScriptedTransform( $this, $script, $params );
 881                                 if ( $thumb ) {
 882                                         break;
 883                                 }
 884                         }
 885
 886                         $normalisedParams = $params;
 887                         $handler->normaliseParams( $this, $normalisedParams );
 888
 889                         $thumbName = $this->thumbName( $normalisedParams );
 890                         $thumbUrl = $this->getThumbUrl( $thumbName );
 891                         $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
 892
 893                         if ( $this->repo ) {
 894                                 // Defer rendering if a 404 handler is set up...
 895                                 if ( $this->repo->canTransformVia404() && !( $flags & self::RENDER_NOW ) ) {
 896                                         wfDebug( __METHOD__ . " transformation deferred." );
 897                                         // XXX: Pass in the storage path even though we are not rendering anything
 898                                         // and the path is supposed to be an FS path. This is due to getScalerType()
 899                                         // getting called on the path and clobbering $thumb->getUrl() if it's false.
 900                                         $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 901                                         break;
 902                                 }
 903                                 // Clean up broken thumbnails as needed
 904                                 $this->migrateThumbFile( $thumbName );
 905                                 // Check if an up-to-date thumbnail already exists...
 906                                 wfDebug( __METHOD__.": Doing stat for $thumbPath\n" );
 907                                 if ( !( $flags & self::RENDER_FORCE ) && $this->repo->fileExists( $thumbPath ) ) {
 908                                         $timestamp = $this->repo->getFileTimestamp( $thumbPath );
 909                                         if ( $timestamp !== false && $timestamp >= $wgThumbnailEpoch ) {
 910                                                 // XXX: Pass in the storage path even though we are not rendering anything
 911                                                 // and the path is supposed to be an FS path. This is due to getScalerType()
 912                                                 // getting called on the path and clobbering $thumb->getUrl() if it's false.
 913                                                 $thumb = $handler->getTransform(
 914                                                         $this, $thumbPath, $thumbUrl, $params );
 915                                                 $thumb->setStoragePath( $thumbPath );
 916                                                 break;
 917                                         }
 918                                 } elseif ( $flags & self::RENDER_FORCE ) {
 919                                         wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
 920                                 }
 921                         }
 922
 923                         // If the backend is ready-only, don't keep generating thumbnails
 924                         // only to return transformation errors, just return the error now.
 925                         if ( $this->repo->getReadOnlyReason() !== false ) {
 926                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
 927                                 break;
 928                         }
 929
 930                         // Create a temp FS file with the same extension and the thumbnail
 931                         $thumbExt = FileBackend::extensionFromPath( $thumbPath );
 932                         $tmpFile = TempFSFile::factory( 'transform_', $thumbExt );
 933                         if ( !$tmpFile ) {
 934                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
 935                                 break;
 936                         }
 937                         $tmpThumbPath = $tmpFile->getPath(); // path of 0-byte temp file
 938
 939                         // Actually render the thumbnail...
 940                         wfProfileIn( __METHOD__ . '-doTransform' );
 941                         $thumb = $handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $params );
 942                         wfProfileOut( __METHOD__ . '-doTransform' );
 943                         $tmpFile->bind( $thumb ); // keep alive with $thumb
 944
 945                         if ( !$thumb ) { // bad params?
 946                                 $thumb = null;
 947                         } elseif ( $thumb->isError() ) { // transform error
 948                                 $this->lastError = $thumb->toText();
 949                                 // Ignore errors if requested
 950                                 if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 951                                         $thumb = $handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $params );
 952                                 }
 953                         } elseif ( $this->repo && $thumb->hasFile() && !$thumb->fileIsSource() ) {
 954                                 // Copy the thumbnail from the file system into storage...
 955                                 $disposition = $this->getThumbDisposition( $thumbName );
 956                                 $status = $this->repo->quickImport( $tmpThumbPath, $thumbPath, $disposition );
 957                                 if ( $status->isOK() ) {
 958                                         $thumb->setStoragePath( $thumbPath );
 959                                 } else {
 960                                         $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
 961                                 }
 962                                 // Give extensions a chance to do something with this thumbnail...
 963                                 wfRunHooks( 'FileTransformed', array( $this, $thumb, $tmpThumbPath, $thumbPath ) );
 964                         }
 965
 966                         // Purge. Useful in the event of Core -> Squid connection failure or squid
 967                         // purge collisions from elsewhere during failure. Don't keep triggering for
 968                         // "thumbs" which have the main image URL though (bug 13776)
 969                         if ( $wgUseSquid ) {
 970                                 if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
 971                                         SquidUpdate::purge( array( $thumbUrl ) );
 972                                 }
 973                         }
 974                 } while ( false );
 975
 976                 wfProfileOut( __METHOD__ );
 977                 return is_object( $thumb ) ? $thumb : false;
 978         }
 979
 980         /**
 981          * @param $thumbName string Thumbnail name
 982          * @return string Content-Disposition header value
 983          */
 984         function getThumbDisposition( $thumbName ) {
 985                 $fileName = $this->name; // file name to suggest
 986                 $thumbExt = FileBackend::extensionFromPath( $thumbName );
 987                 if ( $thumbExt != '' && $thumbExt !== $this->getExtension() ) {
 988                         $fileName .= ".$thumbExt";
 989                 }
 990                 return FileBackend::makeContentDisposition( 'inline', $fileName );
 991         }
 992
 993         /**
 994          * Hook into transform() to allow migration of thumbnail files
 995          * STUB
 996          * Overridden by LocalFile
 997          */
 998         function migrateThumbFile( $thumbName ) {}
 999
1000         /**
1001          * Get a MediaHandler instance for this file
1002          *
1003          * @return MediaHandler
1004          */
1005         function getHandler() {
1006                 if ( !isset( $this->handler ) ) {
1007                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
1008                 }
1009                 return $this->handler;
1010         }
1011
1012         /**
1013          * Get a ThumbnailImage representing a file type icon
1014          *
1015          * @return ThumbnailImage
1016          */
1017         function iconThumb() {
1018                 global $wgStylePath, $wgStyleDirectory;
1019
1020                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
1021                 foreach ( $try as $icon ) {
1022                         $path = '/common/images/icons/' . $icon;
1023                         $filepath = $wgStyleDirectory . $path;
1024                         if ( file_exists( $filepath ) ) { // always FS
1025                                 $params = array( 'width' => 120, 'height' => 120 );
1026                                 return new ThumbnailImage( $this, $wgStylePath . $path, false, $params );
1027                         }
1028                 }
1029                 return null;
1030         }
1031
1032         /**
1033          * Get last thumbnailing error.
1034          * Largely obsolete.
1035          */
1036         function getLastError() {
1037                 return $this->lastError;
1038         }
1039
1040         /**
1041          * Get all thumbnail names previously generated for this file
1042          * STUB
1043          * Overridden by LocalFile
1044          * @return array
1045          */
1046         function getThumbnails() {
1047                 return array();
1048         }
1049
1050         /**
1051          * Purge shared caches such as thumbnails and DB data caching
1052          * STUB
1053          * Overridden by LocalFile
1054          * @param $options Array Options, which include:
1055          *     'forThumbRefresh' : The purging is only to refresh thumbnails
1056          */
1057         function purgeCache( $options = array() ) {}
1058
1059         /**
1060          * Purge the file description page, but don't go after
1061          * pages using the file. Use when modifying file history
1062          * but not the current data.
1063          */
1064         function purgeDescription() {
1065                 $title = $this->getTitle();
1066                 if ( $title ) {
1067                         $title->invalidateCache();
1068                         $title->purgeSquid();
1069                 }
1070         }
1071
1072         /**
1073          * Purge metadata and all affected pages when the file is created,
1074          * deleted, or majorly updated.
1075          */
1076         function purgeEverything() {
1077                 // Delete thumbnails and refresh file metadata cache
1078                 $this->purgeCache();
1079                 $this->purgeDescription();
1080
1081                 // Purge cache of all pages using this file
1082                 $title = $this->getTitle();
1083                 if ( $title ) {
1084                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
1085                         $update->doUpdate();
1086                 }
1087         }
1088
1089         /**
1090          * Return a fragment of the history of file.
1091          *
1092          * STUB
1093          * @param $limit integer Limit of rows to return
1094          * @param $start string timestamp Only revisions older than $start will be returned
1095          * @param $end string timestamp Only revisions newer than $end will be returned
1096          * @param $inc bool Include the endpoints of the time range
1097          *
1098          * @return array
1099          */
1100         function getHistory( $limit = null, $start = null, $end = null, $inc=true ) {
1101                 return array();
1102         }
1103
1104         /**
1105          * Return the history of this file, line by line. Starts with current version,
1106          * then old versions. Should return an object similar to an image/oldimage
1107          * database row.
1108          *
1109          * STUB
1110          * Overridden in LocalFile
1111          * @return bool
1112          */
1113         public function nextHistoryLine() {
1114                 return false;
1115         }
1116
1117         /**
1118          * Reset the history pointer to the first element of the history.
1119          * Always call this function after using nextHistoryLine() to free db resources
1120          * STUB
1121          * Overridden in LocalFile.
1122          */
1123         public function resetHistory() {}
1124
1125         /**
1126          * Get the filename hash component of the directory including trailing slash,
1127          * e.g. f/fa/
1128          * If the repository is not hashed, returns an empty string.
1129          *
1130          * @return string
1131          */
1132         function getHashPath() {
1133                 if ( !isset( $this->hashPath ) ) {
1134                         $this->assertRepoDefined();
1135                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1136                 }
1137                 return $this->hashPath;
1138         }
1139
1140         /**
1141          * Get the path of the file relative to the public zone root.
1142          * This function is overriden in OldLocalFile to be like getArchiveRel().
1143          *
1144          * @return string
1145          */
1146         function getRel() {
1147                 return $this->getHashPath() . $this->getName();
1148         }
1149
1150         /**
1151          * Get the path of an archived file relative to the public zone root
1152          *
1153          * @param $suffix bool|string if not false, the name of an archived thumbnail file
1154          *
1155          * @return string
1156          */
1157         function getArchiveRel( $suffix = false ) {
1158                 $path = 'archive/' . $this->getHashPath();
1159                 if ( $suffix === false ) {
1160                         $path = substr( $path, 0, -1 );
1161                 } else {
1162                         $path .= $suffix;
1163                 }
1164                 return $path;
1165         }
1166
1167         /**
1168          * Get the path, relative to the thumbnail zone root, of the
1169          * thumbnail directory or a particular file if $suffix is specified
1170          *
1171          * @param $suffix bool|string if not false, the name of a thumbnail file
1172          *
1173          * @return string
1174          */
1175         function getThumbRel( $suffix = false ) {
1176                 $path = $this->getRel();
1177                 if ( $suffix !== false ) {
1178                         $path .= '/' . $suffix;
1179                 }
1180                 return $path;
1181         }
1182
1183         /**
1184          * Get urlencoded path of the file relative to the public zone root.
1185          * This function is overriden in OldLocalFile to be like getArchiveUrl().
1186          *
1187          * @return string
1188          */
1189         function getUrlRel() {
1190                 return $this->getHashPath() . rawurlencode( $this->getName() );
1191         }
1192
1193         /**
1194          * Get the path, relative to the thumbnail zone root, for an archived file's thumbs directory
1195          * or a specific thumb if the $suffix is given.
1196          *
1197          * @param $archiveName string the timestamped name of an archived image
1198          * @param $suffix bool|string if not false, the name of a thumbnail file
1199          *
1200          * @return string
1201          */
1202         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1203                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1204                 if ( $suffix === false ) {
1205                         $path = substr( $path, 0, -1 );
1206                 } else {
1207                         $path .= $suffix;
1208                 }
1209                 return $path;
1210         }
1211
1212         /**
1213          * Get the path of the archived file.
1214          *
1215          * @param $suffix bool|string if not false, the name of an archived file.
1216          *
1217          * @return string
1218          */
1219         function getArchivePath( $suffix = false ) {
1220                 $this->assertRepoDefined();
1221                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1222         }
1223
1224         /**
1225          * Get the path of an archived file's thumbs, or a particular thumb if $suffix is specified
1226          *
1227          * @param $archiveName string the timestamped name of an archived image
1228          * @param $suffix bool|string if not false, the name of a thumbnail file
1229          *
1230          * @return string
1231          */
1232         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1233                 $this->assertRepoDefined();
1234                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1235                         $this->getArchiveThumbRel( $archiveName, $suffix );
1236         }
1237
1238         /**
1239          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1240          *
1241          * @param $suffix bool|string if not false, the name of a thumbnail file
1242          *
1243          * @return string
1244          */
1245         function getThumbPath( $suffix = false ) {
1246                 $this->assertRepoDefined();
1247                 return $this->repo->getZonePath( 'thumb' ) . '/' . $this->getThumbRel( $suffix );
1248         }
1249
1250         /**
1251          * Get the URL of the archive directory, or a particular file if $suffix is specified
1252          *
1253          * @param $suffix bool|string if not false, the name of an archived file
1254          *
1255          * @return string
1256          */
1257         function getArchiveUrl( $suffix = false ) {
1258                 $this->assertRepoDefined();
1259                 $ext = $this->getExtension();
1260                 $path = $this->repo->getZoneUrl( 'public', $ext ) . '/archive/' . $this->getHashPath();
1261                 if ( $suffix === false ) {
1262                         $path = substr( $path, 0, -1 );
1263                 } else {
1264                         $path .= rawurlencode( $suffix );
1265                 }
1266                 return $path;
1267         }
1268
1269         /**
1270          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1271          *
1272          * @param $archiveName string the timestamped name of an archived image
1273          * @param $suffix bool|string if not false, the name of a thumbnail file
1274          *
1275          * @return string
1276          */
1277         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1278                 $this->assertRepoDefined();
1279                 $ext = $this->getExtension();
1280                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/archive/' .
1281                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1282                 if ( $suffix === false ) {
1283                         $path = substr( $path, 0, -1 );
1284                 } else {
1285                         $path .= rawurlencode( $suffix );
1286                 }
1287                 return $path;
1288         }
1289
1290         /**
1291          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1292          *
1293          * @param $suffix bool|string if not false, the name of a thumbnail file
1294          *
1295          * @return string path
1296          */
1297         function getThumbUrl( $suffix = false ) {
1298                 $this->assertRepoDefined();
1299                 $ext = $this->getExtension();
1300                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/' . $this->getUrlRel();
1301                 if ( $suffix !== false ) {
1302                         $path .= '/' . rawurlencode( $suffix );
1303                 }
1304                 return $path;
1305         }
1306
1307         /**
1308          * Get the public zone virtual URL for a current version source file
1309          *
1310          * @param $suffix bool|string if not false, the name of a thumbnail file
1311          *
1312          * @return string
1313          */
1314         function getVirtualUrl( $suffix = false ) {
1315                 $this->assertRepoDefined();
1316                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1317                 if ( $suffix !== false ) {
1318                         $path .= '/' . rawurlencode( $suffix );
1319                 }
1320                 return $path;
1321         }
1322
1323         /**
1324          * Get the public zone virtual URL for an archived version source file
1325          *
1326          * @param $suffix bool|string if not false, the name of a thumbnail file
1327          *
1328          * @return string
1329          */
1330         function getArchiveVirtualUrl( $suffix = false ) {
1331                 $this->assertRepoDefined();
1332                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1333                 if ( $suffix === false ) {
1334                         $path = substr( $path, 0, -1 );
1335                 } else {
1336                         $path .= rawurlencode( $suffix );
1337                 }
1338                 return $path;
1339         }
1340
1341         /**
1342          * Get the virtual URL for a thumbnail file or directory
1343          *
1344          * @param $suffix bool|string if not false, the name of a thumbnail file
1345          *
1346          * @return string
1347          */
1348         function getThumbVirtualUrl( $suffix = false ) {
1349                 $this->assertRepoDefined();
1350                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1351                 if ( $suffix !== false ) {
1352                         $path .= '/' . rawurlencode( $suffix );
1353                 }
1354                 return $path;
1355         }
1356
1357         /**
1358          * @return bool
1359          */
1360         function isHashed() {
1361                 $this->assertRepoDefined();
1362                 return (bool)$this->repo->getHashLevels();
1363         }
1364
1365         /**
1366          * @throws MWException
1367          */
1368         function readOnlyError() {
1369                 throw new MWException( get_class($this) . ': write operations are not supported' );
1370         }
1371
1372         /**
1373          * Record a file upload in the upload log and the image table
1374          * STUB
1375          * Overridden by LocalFile
1376          * @param $oldver
1377          * @param $desc
1378          * @param $license string
1379          * @param $copyStatus string
1380          * @param $source string
1381          * @param $watch bool
1382          */
1383         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '', $watch = false ) {
1384                 $this->readOnlyError();
1385         }
1386
1387         /**
1388          * Move or copy a file to its public location. If a file exists at the
1389          * destination, move it to an archive. Returns a FileRepoStatus object with
1390          * the archive name in the "value" member on success.
1391          *
1392          * The archive name should be passed through to recordUpload for database
1393          * registration.
1394          *
1395          * Options to $options include:
1396          *   - headers : name/value map of HTTP headers to use in response to GET/HEAD requests
1397          *
1398          * @param $srcPath String: local filesystem path to the source image
1399          * @param $flags Integer: a bitwise combination of:
1400          *     File::DELETE_SOURCE    Delete the source file, i.e. move
1401          *         rather than copy
1402          * @param $options Array Optional additional parameters
1403          * @return FileRepoStatus object. On success, the value member contains the
1404          *     archive name, or an empty string if it was a new file.
1405          *
1406          * STUB
1407          * Overridden by LocalFile
1408          */
1409         function publish( $srcPath, $flags = 0, array $options = array() ) {
1410                 $this->readOnlyError();
1411         }
1412
1413         /**
1414          * @return bool
1415          */
1416         function formatMetadata() {
1417                 if ( !$this->getHandler() ) {
1418                         return false;
1419                 }
1420                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
1421         }
1422
1423         /**
1424          * Returns true if the file comes from the local file repository.
1425          *
1426          * @return bool
1427          */
1428         function isLocal() {
1429                 return $this->repo && $this->repo->isLocal();
1430         }
1431
1432         /**
1433          * Returns the name of the repository.
1434          *
1435          * @return string
1436          */
1437         function getRepoName() {
1438                 return $this->repo ? $this->repo->getName() : 'unknown';
1439         }
1440
1441         /**
1442          * Returns the repository
1443          *
1444          * @return FileRepo|bool
1445          */
1446         function getRepo() {
1447                 return $this->repo;
1448         }
1449
1450         /**
1451          * Returns true if the image is an old version
1452          * STUB
1453          *
1454          * @return bool
1455          */
1456         function isOld() {
1457                 return false;
1458         }
1459
1460         /**
1461          * Is this file a "deleted" file in a private archive?
1462          * STUB
1463          *
1464          * @param $field
1465          *
1466          * @return bool
1467          */
1468         function isDeleted( $field ) {
1469                 return false;
1470         }
1471
1472         /**
1473          * Return the deletion bitfield
1474          * STUB
1475          * @return int
1476          */
1477         function getVisibility() {
1478                 return 0;
1479         }
1480
1481         /**
1482          * Was this file ever deleted from the wiki?
1483          *
1484          * @return bool
1485          */
1486         function wasDeleted() {
1487                 $title = $this->getTitle();
1488                 return $title && $title->isDeletedQuick();
1489         }
1490
1491         /**
1492          * Move file to the new title
1493          *
1494          * Move current, old version and all thumbnails
1495          * to the new filename. Old file is deleted.
1496          *
1497          * Cache purging is done; checks for validity
1498          * and logging are caller's responsibility
1499          *
1500          * @param $target Title New file name
1501          * @return FileRepoStatus object.
1502          */
1503          function move( $target ) {
1504                 $this->readOnlyError();
1505          }
1506
1507         /**
1508          * Delete all versions of the file.
1509          *
1510          * Moves the files into an archive directory (or deletes them)
1511          * and removes the database rows.
1512          *
1513          * Cache purging is done; logging is caller's responsibility.
1514          *
1515          * @param $reason String
1516          * @param $suppress Boolean: hide content from sysops?
1517          * @return bool on success, false on some kind of failure
1518          * STUB
1519          * Overridden by LocalFile
1520          */
1521         function delete( $reason, $suppress = false ) {
1522                 $this->readOnlyError();
1523         }
1524
1525         /**
1526          * Restore all or specified deleted revisions to the given file.
1527          * Permissions and logging are left to the caller.
1528          *
1529          * May throw database exceptions on error.
1530          *
1531          * @param $versions array set of record ids of deleted items to restore,
1532          *                    or empty to restore all revisions.
1533          * @param $unsuppress bool remove restrictions on content upon restoration?
1534          * @return int|bool the number of file revisions restored if successful,
1535          *         or false on failure
1536          * STUB
1537          * Overridden by LocalFile
1538          */
1539         function restore( $versions = array(), $unsuppress = false ) {
1540                 $this->readOnlyError();
1541         }
1542
1543         /**
1544          * Returns 'true' if this file is a type which supports multiple pages,
1545          * e.g. DJVU or PDF. Note that this may be true even if the file in
1546          * question only has a single page.
1547          *
1548          * @return Bool
1549          */
1550         function isMultipage() {
1551                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1552         }
1553
1554         /**
1555          * Returns the number of pages of a multipage document, or false for
1556          * documents which aren't multipage documents
1557          *
1558          * @return bool|int
1559          */
1560         function pageCount() {
1561                 if ( !isset( $this->pageCount ) ) {
1562                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1563                                 $this->pageCount = $this->handler->pageCount( $this );
1564                         } else {
1565                                 $this->pageCount = false;
1566                         }
1567                 }
1568                 return $this->pageCount;
1569         }
1570
1571         /**
1572          * Calculate the height of a thumbnail using the source and destination width
1573          *
1574          * @param $srcWidth
1575          * @param $srcHeight
1576          * @param $dstWidth
1577          *
1578          * @return int
1579          */
1580         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1581                 // Exact integer multiply followed by division
1582                 if ( $srcWidth == 0 ) {
1583                         return 0;
1584                 } else {
1585                         return round( $srcHeight * $dstWidth / $srcWidth );
1586                 }
1587         }
1588
1589         /**
1590          * Get an image size array like that returned by getImageSize(), or false if it
1591          * can't be determined.
1592          *
1593          * @param $fileName String: The filename
1594          * @return Array
1595          */
1596         function getImageSize( $fileName ) {
1597                 if ( !$this->getHandler() ) {
1598                         return false;
1599                 }
1600                 return $this->handler->getImageSize( $this, $fileName );
1601         }
1602
1603         /**
1604          * Get the URL of the image description page. May return false if it is
1605          * unknown or not applicable.
1606          *
1607          * @return string
1608          */
1609         function getDescriptionUrl() {
1610                 if ( $this->repo ) {
1611                         return $this->repo->getDescriptionUrl( $this->getName() );
1612                 } else {
1613                         return false;
1614                 }
1615         }
1616
1617         /**
1618          * Get the HTML text of the description page, if available
1619          *
1620          * @return string
1621          */
1622         function getDescriptionText() {
1623                 global $wgMemc, $wgLang;
1624                 if ( !$this->repo || !$this->repo->fetchDescription ) {
1625                         return false;
1626                 }
1627                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $wgLang->getCode() );
1628                 if ( $renderUrl ) {
1629                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1630                                 wfDebug("Attempting to get the description from cache...");
1631                                 $key = $this->repo->getLocalCacheKey( 'RemoteFileDescription', 'url', $wgLang->getCode(),
1632                                                                         $this->getName() );
1633                                 $obj = $wgMemc->get($key);
1634                                 if ($obj) {
1635                                         wfDebug("success!\n");
1636                                         return $obj;
1637                                 }
1638                                 wfDebug("miss\n");
1639                         }
1640                         wfDebug( "Fetching shared description from $renderUrl\n" );
1641                         $res = Http::get( $renderUrl );
1642                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1643                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1644                         }
1645                         return $res;
1646                 } else {
1647                         return false;
1648                 }
1649         }
1650
1651         /**
1652          * Get description of file revision
1653          * STUB
1654          *
1655          * @param $audience Integer: one of:
1656          *      File::FOR_PUBLIC       to be displayed to all users
1657          *      File::FOR_THIS_USER    to be displayed to the given user
1658          *      File::RAW              get the description regardless of permissions
1659          * @param $user User object to check for, only if FOR_THIS_USER is passed
1660          *              to the $audience parameter
1661          * @return string
1662          */
1663         function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
1664                 return null;
1665         }
1666
1667         /**
1668          * Get the 14-character timestamp of the file upload
1669          *
1670          * @return string|bool TS_MW timestamp or false on failure
1671          */
1672         function getTimestamp() {
1673                 $this->assertRepoDefined();
1674                 return $this->repo->getFileTimestamp( $this->getPath() );
1675         }
1676
1677         /**
1678          * Get the SHA-1 base 36 hash of the file
1679          *
1680          * @return string
1681          */
1682         function getSha1() {
1683                 $this->assertRepoDefined();
1684                 return $this->repo->getFileSha1( $this->getPath() );
1685         }
1686
1687         /**
1688          * Get the deletion archive key, "<sha1>.<ext>"
1689          *
1690          * @return string
1691          */
1692         function getStorageKey() {
1693                 $hash = $this->getSha1();
1694                 if ( !$hash ) {
1695                         return false;
1696                 }
1697                 $ext = $this->getExtension();
1698                 $dotExt = $ext === '' ? '' : ".$ext";
1699                 return $hash . $dotExt;
1700         }
1701
1702         /**
1703          * Determine if the current user is allowed to view a particular
1704          * field of this file, if it's marked as deleted.
1705          * STUB
1706          * @param $field Integer
1707          * @param $user User object to check, or null to use $wgUser
1708          * @return Boolean
1709          */
1710         function userCan( $field, User $user = null ) {
1711                 return true;
1712         }
1713
1714         /**
1715          * Get an associative array containing information about a file in the local filesystem.
1716          *
1717          * @param $path String: absolute local filesystem path
1718          * @param $ext Mixed: the file extension, or true to extract it from the filename.
1719          *             Set it to false to ignore the extension.
1720          *
1721          * @return array
1722          */
1723         static function getPropsFromPath( $path, $ext = true ) {
1724                 wfDebug( __METHOD__.": Getting file info for $path\n" );
1725                 wfDeprecated( __METHOD__, '1.19' );
1726
1727                 $fsFile = new FSFile( $path );
1728                 return $fsFile->getProps();
1729         }
1730
1731         /**
1732          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1733          * encoding, zero padded to 31 digits.
1734          *
1735          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1736          * fairly neatly.
1737          *
1738          * @param $path string
1739          *
1740          * @return bool|string False on failure
1741          */
1742         static function sha1Base36( $path ) {
1743                 wfDeprecated( __METHOD__, '1.19' );
1744
1745                 $fsFile = new FSFile( $path );
1746                 return $fsFile->getSha1Base36();
1747         }
1748
1749         /**
1750          * @return Array HTTP header name/value map to use for HEAD/GET request responses
1751          */
1752         function getStreamHeaders() {
1753                 $handler = $this->getHandler();
1754                 if ( $handler ) {
1755                         return $handler->getStreamHeaders( $this->getMetadata() );
1756                 } else {
1757                         return array();
1758                 }
1759         }
1760
1761         /**
1762          * @return string
1763          */
1764         function getLongDesc() {
1765                 $handler = $this->getHandler();
1766                 if ( $handler ) {
1767                         return $handler->getLongDesc( $this );
1768                 } else {
1769                         return MediaHandler::getGeneralLongDesc( $this );
1770                 }
1771         }
1772
1773         /**
1774          * @return string
1775          */
1776         function getShortDesc() {
1777                 $handler = $this->getHandler();
1778                 if ( $handler ) {
1779                         return $handler->getShortDesc( $this );
1780                 } else {
1781                         return MediaHandler::getGeneralShortDesc( $this );
1782                 }
1783         }
1784
1785         /**
1786          * @return string
1787          */
1788         function getDimensionsString() {
1789                 $handler = $this->getHandler();
1790                 if ( $handler ) {
1791                         return $handler->getDimensionsString( $this );
1792                 } else {
1793                         return '';
1794                 }
1795         }
1796
1797         /**
1798          * @return
1799          */
1800         function getRedirected() {
1801                 return $this->redirected;
1802         }
1803
1804         /**
1805          * @return Title|null
1806          */
1807         function getRedirectedTitle() {
1808                 if ( $this->redirected ) {
1809                         if ( !$this->redirectTitle ) {
1810                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1811                         }
1812                         return $this->redirectTitle;
1813                 }
1814                 return null;
1815         }
1816
1817         /**
1818          * @param  $from
1819          * @return void
1820          */
1821         function redirectedFrom( $from ) {
1822                 $this->redirected = $from;
1823         }
1824
1825         /**
1826          * @return bool
1827          */
1828         function isMissing() {
1829                 return false;
1830         }
1831
1832         /**
1833          * Check if this file object is small and can be cached
1834          * @return boolean
1835          */
1836         public function isCacheable() {
1837                 return true;
1838         }
1839
1840         /**
1841          * Assert that $this->repo is set to a valid FileRepo instance
1842          * @throws MWException
1843          */
1844         protected function assertRepoDefined() {
1845                 if ( !( $this->repo instanceof $this->repoClass ) ) {
1846                         throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
1847                 }
1848         }
1849
1850         /**
1851          * Assert that $this->title is set to a Title
1852          * @throws MWException
1853          */
1854         protected function assertTitleDefined() {
1855                 if ( !( $this->title instanceof Title ) ) {
1856                         throw new MWException( "A Title object is not set for this File.\n" );
1857                 }
1858         }
1859 }