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