includes/Content.php

   1 <?php
   2 /**
   3  * A content object represents page content, e.g. the text to show on a page.
   4  * Content objects have no knowledge about how they relate to wiki pages.
   5  *
   6  * @since 1.WD
   7  */
   8 interface Content {
   9
  10         /**
  11          * @since WD.1
  12          *
  13          * @return string A string representing the content in a way useful for
  14          *   building a full text search index. If no useful representation exists,
  15          *   this method returns an empty string.
  16          *
  17          * @todo: test that this actually works
  18          * @todo: make sure this also works with LuceneSearch / WikiSearch
  19          */
  20         public function getTextForSearchIndex( );
  21
  22         /**
  23          * @since WD.1
  24          *
  25          * @return string The wikitext to include when another page includes this
  26          * content, or false if the content is not includable in a wikitext page.
  27          *
  28          * @TODO: allow native handling, bypassing wikitext representation, like
  29          *    for includable special pages.
  30          * @TODO: allow transclusion into other content models than Wikitext!
  31          * @TODO: used in WikiPage and MessageCache to get message text. Not so
  32          *    nice. What should we use instead?!
  33          */
  34         public function getWikitextForTransclusion( );
  35
  36         /**
  37          * Returns a textual representation of the content suitable for use in edit
  38          * summaries and log messages.
  39          *
  40          * @since WD.1
  41          *
  42          * @param $maxlength int Maximum length of the summary text
  43          * @return   The summary text
  44          */
  45         public function getTextForSummary( $maxlength = 250 );
  46
  47         /**
  48          * Returns native representation of the data. Interpretation depends on
  49          * the data model used, as given by getDataModel().
  50          *
  51          * @since WD.1
  52          *
  53          * @return mixed The native representation of the content. Could be a
  54          *    string, a nested array structure, an object, a binary blob...
  55          *    anything, really.
  56          *
  57          * @NOTE: review all calls carefully, caller must be aware of content model!
  58          */
  59         public function getNativeData( );
  60
  61         /**
  62          * Returns the content's nominal size in bogo-bytes.
  63          *
  64          * @return int
  65          */
  66         public function getSize( );
  67
  68         /**
  69          * Returns the ID of the content model used by this Content object.
  70          * Corresponds to the CONTENT_MODEL_XXX constants.
  71          *
  72          * @since WD.1
  73          *
  74          * @return String The model id
  75          */
  76         public function getModel();
  77
  78         /**
  79          * Convenience method that returns the ContentHandler singleton for handling
  80          * the content model that this Content object uses.
  81          *
  82          * Shorthand for ContentHandler::getForContent( $this )
  83          *
  84          * @since WD.1
  85          *
  86          * @return ContentHandler
  87          */
  88         public function getContentHandler();
  89
  90         /**
  91          * Convenience method that returns the default serialization format for the
  92          * content model that this Content object uses.
  93          *
  94          * Shorthand for $this->getContentHandler()->getDefaultFormat()
  95          *
  96          * @since WD.1
  97          *
  98          * @return String
  99          */
 100         public function getDefaultFormat();
 101
 102         /**
 103          * Convenience method that returns the list of serialization formats
 104          * supported for the content model that this Content object uses.
 105          *
 106          * Shorthand for $this->getContentHandler()->getSupportedFormats()
 107          *
 108          * @since WD.1
 109          *
 110          * @return Array of supported serialization formats
 111          */
 112         public function getSupportedFormats();
 113
 114         /**
 115          * Returns true if $format is a supported serialization format for this
 116          * Content object, false if it isn't.
 117          *
 118          * Note that this should always return true if $format is null, because null
 119          * stands for the default serialization.
 120          *
 121          * Shorthand for $this->getContentHandler()->isSupportedFormat( $format )
 122          *
 123          * @since WD.1
 124          *
 125          * @param $format string The format to check
 126          * @return bool Whether the format is supported
 127          */
 128         public function isSupportedFormat( $format );
 129
 130         /**
 131          * Convenience method for serializing this Content object.
 132          *
 133          * Shorthand for $this->getContentHandler()->serializeContent( $this, $format )
 134          *
 135          * @since WD.1
 136          *
 137          * @param $format null|string The desired serialization format (or null for
 138          *    the default format).
 139          * @return string Serialized form of this Content object
 140          */
 141         public function serialize( $format = null );
 142
 143         /**
 144          * Returns true if this Content object represents empty content.
 145          *
 146          * @since WD.1
 147          *
 148          * @return bool Whether this Content object is empty
 149          */
 150         public function isEmpty();
 151
 152         /**
 153          * Returns whether the content is valid. This is intended for local validity
 154          * checks, not considering global consistency.
 155          *
 156          * Content needs to be valid before it can be saved.
 157          *
 158          * This default implementation always returns true.
 159          *
 160          * @since WD.1
 161          *
 162          * @return boolean
 163          */
 164         public function isValid();
 165
 166         /**
 167          * Returns true if this Content objects is conceptually equivalent to the
 168          * given Content object.
 169          *
 170          * Contract:
 171          *
 172          * - Will return false if $that is null.
 173          * - Will return true if $that === $this.
 174          * - Will return false if $that->getModelName() != $this->getModel().
 175          * - Will return false if $that->getNativeData() is not equal to $this->getNativeData(),
 176          *   where the meaning of "equal" depends on the actual data model.
 177          *
 178          * Implementations should be careful to make equals() transitive and reflexive:
 179          *
 180          * - $a->equals( $b ) <=> $b->equals( $a )
 181          * - $a->equals( $b ) &&  $b->equals( $c ) ==> $a->equals( $c )
 182          *
 183          * @since WD.1
 184          *
 185          * @param $that Content The Content object to compare to
 186          * @return bool True if this Content object is equal to $that, false otherwise.
 187          */
 188         public function equals( Content $that = null );
 189
 190         /**
 191          * Return a copy of this Content object. The following must be true for the
 192          * object returned:
 193          *
 194          * if $copy = $original->copy()
 195          *
 196          * - get_class($original) === get_class($copy)
 197          * - $original->getModel() === $copy->getModel()
 198          * - $original->equals( $copy )
 199          *
 200          * If and only if the Content object is immutable, the copy() method can and
 201          * should return $this. That is,  $copy === $original may be true, but only
 202          * for immutable content objects.
 203          *
 204          * @since WD.1
 205          *
 206          * @return Content. A copy of this object
 207          */
 208         public function copy( );
 209
 210         /**
 211          * Returns true if this content is countable as a "real" wiki page, provided
 212          * that it's also in a countable location (e.g. a current revision in the
 213          * main namespace).
 214          *
 215          * @since WD.1
 216          *
 217          * @param $hasLinks Bool: If it is known whether this content contains
 218          *    links, provide this information here, to avoid redundant parsing to
 219          *    find out.
 220          * @return boolean
 221          */
 222         public function isCountable( $hasLinks = null ) ;
 223
 224
 225         /**
 226          * Parse the Content object and generate a ParserOutput from the result.
 227          * $result->getText() can be used to obtain the generated HTML. If no HTML
 228          * is needed, $generateHtml can be set to false; in that case,
 229          * $result->getText() may return null.
 230          *
 231          * @param $title Title The page title to use as a context for rendering
 232          * @param $revId null|int The revision being rendered (optional)
 233          * @param $options null|ParserOptions Any parser options
 234          * @param $generateHtml Boolean Whether to generate HTML (default: true). If false,
 235          *        the result of calling getText() on the ParserOutput object returned by
 236          *        this method is undefined.
 237          *
 238          * @since WD.1
 239          *
 240          * @return ParserOutput
 241          */
 242         public function getParserOutput( Title $title,
 243                 $revId = null,
 244                 ParserOptions $options = null, $generateHtml = true );
 245         # TODO: make RenderOutput and RenderOptions base classes
 246
 247         /**
 248          * Returns a list of DataUpdate objects for recording information about this
 249          * Content in some secondary data store. If the optional second argument,
 250          * $old, is given, the updates may model only the changes that need to be
 251          * made to replace information about the old content with information about
 252          * the new content.
 253          *
 254          * This default implementation calls
 255          * $this->getParserOutput( $content, $title, null, null, false ),
 256          * and then calls getSecondaryDataUpdates( $title, $recursive ) on the
 257          * resulting ParserOutput object.
 258          *
 259          * Subclasses may implement this to determine the necessary updates more
 260          * efficiently, or make use of information about the old content.
 261          *
 262          * @param $title Title The context for determining the necessary updates
 263          * @param $old Content|null An optional Content object representing the
 264          *    previous content, i.e. the content being replaced by this Content
 265          *    object.
 266          * @param $recursive boolean Whether to include recursive updates (default:
 267          *    false).
 268          * @param $parserOutput ParserOutput|null Optional ParserOutput object.
 269          *    Provide if you have one handy, to avoid re-parsing of the content.
 270          *
 271          * @return Array. A list of DataUpdate objects for putting information
 272          *    about this content object somewhere.
 273          *
 274          * @since WD.1
 275          */
 276         public function getSecondaryDataUpdates( Title $title,
 277                 Content $old = null,
 278                 $recursive = true, ParserOutput $parserOutput = null
 279         );
 280
 281         /**
 282          * Construct the redirect destination from this content and return an
 283          * array of Titles, or null if this content doesn't represent a redirect.
 284          * The last element in the array is the final destination after all redirects
 285          * have been resolved (up to $wgMaxRedirects times).
 286          *
 287          * @since WD.1
 288          *
 289          * @return Array of Titles, with the destination last
 290          */
 291         public function getRedirectChain();
 292
 293         /**
 294          * Construct the redirect destination from this content and return a Title,
 295          * or null if this content doesn't represent a redirect.
 296          * This will only return the immediate redirect target, useful for
 297          * the redirect table and other checks that don't need full recursion.
 298          *
 299          * @since WD.1
 300          *
 301          * @return Title: The corresponding Title
 302          */
 303         public function getRedirectTarget();
 304
 305         /**
 306          * Construct the redirect destination from this content and return the
 307          * Title, or null if this content doesn't represent a redirect.
 308          *
 309          * This will recurse down $wgMaxRedirects times or until a non-redirect
 310          * target is hit in order to provide (hopefully) the Title of the final
 311          * destination instead of another redirect.
 312          *
 313          * There is usually no need to override the default behaviour, subclasses that
 314          * want to implement redirects should override getRedirectTarget().
 315          *
 316          * @since WD.1
 317          *
 318          * @return Title
 319          */
 320         public function getUltimateRedirectTarget();
 321
 322         /**
 323          * Returns whether this Content represents a redirect.
 324          * Shorthand for getRedirectTarget() !== null.
 325          *
 326          * @since WD.1
 327          *
 328          * @return bool
 329          */
 330         public function isRedirect();
 331
 332         /**
 333          * Returns the section with the given ID.
 334          *
 335          * @since WD.1
 336          *
 337          * @param $sectionId string The section's ID, given as a numeric string.
 338          *    The ID "0" retrieves the section before the first heading, "1" the
 339          *    text between the first heading (included) and the second heading
 340          *    (excluded), etc.
 341          * @return Content|Boolean|null The section, or false if no such section
 342          *    exist, or null if sections are not supported.
 343          */
 344         public function getSection( $sectionId );
 345
 346         /**
 347          * Replaces a section of the content and returns a Content object with the
 348          * section replaced.
 349          *
 350          * @since WD.1
 351          *
 352          * @param $section Empty/null/false or a section number (0, 1, 2, T1, T2...), or "new"
 353          * @param $with Content: new content of the section
 354          * @param $sectionTitle String: new section's subject, only if $section is 'new'
 355          * @return string Complete article text, or null if error
 356          */
 357         public function replaceSection( $section, Content $with, $sectionTitle = ''  );
 358
 359         /**
 360          * Returns a Content object with pre-save transformations applied (or this
 361          * object if no transformations apply).
 362          *
 363          * @since WD.1
 364          *
 365          * @param $title Title
 366          * @param $user User
 367          * @param $popts null|ParserOptions
 368          * @return Content
 369          */
 370         public function preSaveTransform( Title $title, User $user, ParserOptions $popts );
 371
 372         /**
 373          * Returns a new WikitextContent object with the given section heading
 374          * prepended, if supported. The default implementation just returns this
 375          * Content object unmodified, ignoring the section header.
 376          *
 377          * @since WD.1
 378          *
 379          * @param $header string
 380          * @return Content
 381          */
 382         public function addSectionHeader( $header );
 383
 384         /**
 385          * Returns a Content object with preload transformations applied (or this
 386          * object if no transformations apply).
 387          *
 388          * @since WD.1
 389          *
 390          * @param $title Title
 391          * @param $popts null|ParserOptions
 392          * @return Content
 393          */
 394         public function preloadTransform( Title $title, ParserOptions $popts );
 395
 396         /**
 397          * Prepare Content for saving. Called before Content is saved by WikiPage::doEditContent() and in
 398          * similar places.
 399          *
 400          * This may be used to check the content's consistency with global state. This function should
 401          * NOT write any information to the database.
 402          *
 403          * Note that this method will usually be called inside the same transaction bracket that will be used
 404          * to save the new revision.
 405          *
 406          * Note that this method is called before any update to the page table is performed. This means that
 407          * $page may not yet know a page ID.
 408          *
 409          * @param WikiPage $page The page to be saved.
 410          * @param int      $flags bitfield for use with EDIT_XXX constants, see WikiPage::doEditContent()
 411          * @param int      $baseRevId the ID of the current revision
 412          * @param User     $user
 413          *
 414          * @return Status A status object indicating whether the content was successfully prepared for saving.
 415          *                If the returned status indicates an error, a rollback will be performed and the
 416          *                transaction aborted.
 417          *
 418          * @see see WikiPage::doEditContent()
 419          */
 420         public function prepareSave( WikiPage $page, $flags, $baseRevId, User $user );
 421
 422         /**
 423          * Returns a list of updates to perform when this content is deleted.
 424          * The necessary updates may be taken from the Content object, or depend on
 425          * the current state of the database.
 426          *
 427          * @since WD.1
 428          *
 429          * @param $title \Title the title of the deleted page
 430          * @param $parserOutput null|\ParserOutput optional parser output object
 431          *    for efficient access to meta-information about the content object.
 432          *    Provide if you have one handy.
 433          *
 434          * @return array A list of DataUpdate instances that will clean up the
 435          *    database after deletion.
 436          */
 437         public function getDeletionUpdates( Title $title,
 438                 ParserOutput $parserOutput = null );
 439
 440         # TODO: handle ImagePage and CategoryPage
 441         # TODO: make sure we cover lucene search / wikisearch.
 442         # TODO: make sure ReplaceTemplates still works
 443         # FUTURE: nice&sane integration of GeSHi syntax highlighting
 444         #   [11:59] <vvv> Hooks are ugly; make CodeHighlighter interface and a
 445         #   config to set the class which handles syntax highlighting
 446         #   [12:00] <vvv> And default it to a DummyHighlighter
 447
 448         # TODO: make sure we cover the external editor interface (does anyone actually use that?!)
 449
 450         # TODO: tie into API to provide contentModel for Revisions
 451         # TODO: tie into API to provide serialized version and contentFormat for Revisions
 452         # TODO: tie into API edit interface
 453         # FUTURE: make EditForm plugin for EditPage
 454
 455         # FUTURE: special type for redirects?!
 456         # FUTURE: MultipartMultipart < WikipageContent (Main + Links + X)
 457         # FUTURE: LinksContent < LanguageLinksContent, CategoriesContent
 458 }
 459
 460
 461 /**
 462  * A content object represents page content, e.g. the text to show on a page.
 463  * Content objects have no knowledge about how they relate to Wiki pages.
 464  *
 465  * @since 1.WD
 466  */
 467 abstract class AbstractContent implements Content {
 468
 469         /**
 470          * Name of the content model this Content object represents.
 471          * Use with CONTENT_MODEL_XXX constants
 472          *
 473          * @var string $model_id
 474          */
 475         protected $model_id;
 476
 477         /**
 478          * @param String $model_id
 479          */
 480         public function __construct( $model_id = null ) {
 481                 $this->model_id = $model_id;
 482         }
 483
 484         /**
 485          * @see Content::getModel()
 486          */
 487         public function getModel() {
 488                 return $this->model_id;
 489         }
 490
 491         /**
 492          * Throws an MWException if $model_id is not the id of the content model
 493          * supported by this Content object.
 494          *
 495          * @param $model_id int the model to check
 496          *
 497          * @throws MWException
 498          */
 499         protected function checkModelID( $model_id ) {
 500                 if ( $model_id !== $this->model_id ) {
 501                         throw new MWException( "Bad content model: " .
 502                                 "expected {$this->model_id}  " .
 503                                 "but got $model_id." );
 504                 }
 505         }
 506
 507         /**
 508          * @see Content::getContentHandler()
 509          */
 510         public function getContentHandler() {
 511                 return ContentHandler::getForContent( $this );
 512         }
 513
 514         /**
 515          * @see Content::getDefaultFormat()
 516          */
 517         public function getDefaultFormat() {
 518                 return $this->getContentHandler()->getDefaultFormat();
 519         }
 520
 521         /**
 522          * @see Content::getSupportedFormats()
 523          */
 524         public function getSupportedFormats() {
 525                 return $this->getContentHandler()->getSupportedFormats();
 526         }
 527
 528         /**
 529          * @see Content::isSupportedFormat()
 530          */
 531         public function isSupportedFormat( $format ) {
 532                 if ( !$format ) {
 533                         return true; // this means "use the default"
 534                 }
 535
 536                 return $this->getContentHandler()->isSupportedFormat( $format );
 537         }
 538
 539         /**
 540          * Throws an MWException if $this->isSupportedFormat( $format ) doesn't
 541          * return true.
 542          *
 543          * @param $format
 544          * @throws MWException
 545          */
 546         protected function checkFormat( $format ) {
 547                 if ( !$this->isSupportedFormat( $format ) ) {
 548                         throw new MWException( "Format $format is not supported for content model " .
 549                                 $this->getModel() );
 550                 }
 551         }
 552
 553         /**
 554          * @see Content::serialize
 555          */
 556         public function serialize( $format = null ) {
 557                 return $this->getContentHandler()->serializeContent( $this, $format );
 558         }
 559
 560         /**
 561          * @see Content::isEmpty()
 562          */
 563         public function isEmpty() {
 564                 return $this->getSize() == 0;
 565         }
 566
 567         /**
 568          * @see Content::isValid()
 569          */
 570         public function isValid() {
 571                 return true;
 572         }
 573
 574         /**
 575          * @see Content::equals()
 576          */
 577         public function equals( Content $that = null ) {
 578                 if ( is_null( $that ) ) {
 579                         return false;
 580                 }
 581
 582                 if ( $that === $this ) {
 583                         return true;
 584                 }
 585
 586                 if ( $that->getModel() !== $this->getModel() ) {
 587                         return false;
 588                 }
 589
 590                 return $this->getNativeData() === $that->getNativeData();
 591         }
 592
 593
 594         /**
 595          * Returns a list of DataUpdate objects for recording information about this
 596          * Content in some secondary data store.
 597          *
 598          * This default implementation calls
 599          * $this->getParserOutput( $content, $title, null, null, false ),
 600          * and then calls getSecondaryDataUpdates( $title, $recursive ) on the
 601          * resulting ParserOutput object.
 602          *
 603          * Subclasses may override this to determine the secondary data updates more
 604          * efficiently, preferrably without the need to generate a parser output object.
 605          *
 606          * @see Content::getSecondaryDataUpdates()
 607          *
 608          * @param $title Title The context for determining the necessary updates
 609          * @param $old Content|null An optional Content object representing the
 610          *    previous content, i.e. the content being replaced by this Content
 611          *    object.
 612          * @param $recursive boolean Whether to include recursive updates (default:
 613          *    false).
 614          * @param $parserOutput ParserOutput|null Optional ParserOutput object.
 615          *    Provide if you have one handy, to avoid re-parsing of the content.
 616          *
 617          * @return Array. A list of DataUpdate objects for putting information
 618          *    about this content object somewhere.
 619          *
 620          * @since WD.1
 621          */
 622         public function getSecondaryDataUpdates( Title $title,
 623                 Content $old = null,
 624                 $recursive = true, ParserOutput $parserOutput = null
 625         ) {
 626                 if ( !$parserOutput ) {
 627                         $parserOutput = $this->getParserOutput( $title, null, null, false );
 628                 }
 629
 630                 return $parserOutput->getSecondaryDataUpdates( $title, $recursive );
 631         }
 632
 633
 634         /**
 635          * @see Content::getRedirectChain()
 636          */
 637         public function getRedirectChain() {
 638                 global $wgMaxRedirects;
 639                 $title = $this->getRedirectTarget();
 640                 if ( is_null( $title ) ) {
 641                         return null;
 642                 }
 643                 // recursive check to follow double redirects
 644                 $recurse = $wgMaxRedirects;
 645                 $titles = array( $title );
 646                 while ( --$recurse > 0 ) {
 647                         if ( $title->isRedirect() ) {
 648                                 $page = WikiPage::factory( $title );
 649                                 $newtitle = $page->getRedirectTarget();
 650                         } else {
 651                                 break;
 652                         }
 653                         // Redirects to some special pages are not permitted
 654                         if ( $newtitle instanceOf Title && $newtitle->isValidRedirectTarget() ) {
 655                                 // The new title passes the checks, so make that our current
 656                                 // title so that further recursion can be checked
 657                                 $title = $newtitle;
 658                                 $titles[] = $newtitle;
 659                         } else {
 660                                 break;
 661                         }
 662                 }
 663                 return $titles;
 664         }
 665
 666         /**
 667          * @see Content::getRedirectTarget()
 668          */
 669         public function getRedirectTarget() {
 670                 return null;
 671         }
 672
 673         /**
 674          * @see Content::getUltimateRedirectTarget()
 675          * @note: migrated here from Title::newFromRedirectRecurse
 676          */
 677         public function getUltimateRedirectTarget() {
 678                 $titles = $this->getRedirectChain();
 679                 return $titles ? array_pop( $titles ) : null;
 680         }
 681
 682         /**
 683          * @since WD.1
 684          *
 685          * @return bool
 686          */
 687         public function isRedirect() {
 688                 return $this->getRedirectTarget() !== null;
 689         }
 690
 691         /**
 692          * @see Content::getSection()
 693          */
 694         public function getSection( $sectionId ) {
 695                 return null;
 696         }
 697
 698         /**
 699          * @see Content::replaceSection()
 700          */
 701         public function replaceSection( $section, Content $with, $sectionTitle = ''  ) {
 702                 return null;
 703         }
 704
 705         /**
 706          * @see Content::preSaveTransform()
 707          */
 708         public function preSaveTransform( Title $title, User $user, ParserOptions $popts ) {
 709                 return $this;
 710         }
 711
 712         /**
 713          * @see Content::addSectionHeader()
 714          */
 715         public function addSectionHeader( $header ) {
 716                 return $this;
 717         }
 718
 719         /**
 720          * @see Content::preloadTransform()
 721          */
 722         public function preloadTransform( Title $title, ParserOptions $popts ) {
 723                 return $this;
 724         }
 725
 726         /**
 727          * @see  Content::prepareSave()
 728          */
 729         public function prepareSave( WikiPage $page, $flags, $baseRevId, User $user ) {
 730                 if ( $this->isValid() ) {
 731                         return Status::newGood();
 732                 } else {
 733                         return Status::newFatal( "invalid-content-data" );
 734                 }
 735         }
 736
 737         /**
 738          * Returns a list of updates to perform when this content is deleted.
 739          * The necessary updates may be taken from the Content object, or depend on
 740          * the current state of the database.
 741          *
 742          * @since WD.1
 743          *
 744          * @param $title \Title the title of the deleted page
 745          * @param $parserOutput null|\ParserOutput optional parser output object
 746          *    for efficient access to meta-information about the content object.
 747          *    Provide if you have one handy.
 748          *
 749          * @return array A list of DataUpdate instances that will clean up the
 750          *    database after deletion.
 751          */
 752         public function getDeletionUpdates( Title $title,
 753                 ParserOutput $parserOutput = null )
 754         {
 755                 return array(
 756                         new LinksDeletionUpdate( $title ),
 757                 );
 758         }
 759 }
 760
 761 /**
 762  * Content object implementation for representing flat text.
 763  *
 764  * TextContent instances are immutable
 765  *
 766  * @since WD.1
 767  */
 768 abstract class TextContent extends AbstractContent {
 769
 770         public function __construct( $text, $model_id = null ) {
 771                 parent::__construct( $model_id );
 772
 773                 $this->mText = $text;
 774         }
 775
 776         public function copy() {
 777                 return $this; # NOTE: this is ok since TextContent are immutable.
 778         }
 779
 780         public function getTextForSummary( $maxlength = 250 ) {
 781                 global $wgContLang;
 782
 783                 $text = $this->getNativeData();
 784
 785                 $truncatedtext = $wgContLang->truncate(
 786                         preg_replace( "/[\n\r]/", ' ', $text ),
 787                         max( 0, $maxlength ) );
 788
 789                 return $truncatedtext;
 790         }
 791
 792         /**
 793          * returns the text's size in bytes.
 794          *
 795          * @return int The size
 796          */
 797         public function getSize( ) {
 798                 $text = $this->getNativeData( );
 799                 return strlen( $text );
 800         }
 801
 802         /**
 803          * Returns true if this content is not a redirect, and $wgArticleCountMethod
 804          * is "any".
 805          *
 806          * @param $hasLinks Bool: if it is known whether this content contains links,
 807          * provide this information here, to avoid redundant parsing to find out.
 808          *
 809          * @return bool True if the content is countable
 810          */
 811         public function isCountable( $hasLinks = null ) {
 812                 global $wgArticleCountMethod;
 813
 814                 if ( $this->isRedirect( ) ) {
 815                         return false;
 816                 }
 817
 818                 if (  $wgArticleCountMethod === 'any' ) {
 819                         return true;
 820                 }
 821
 822                 return false;
 823         }
 824
 825         /**
 826          * Returns the text represented by this Content object, as a string.
 827          *
 828          * @param   the raw text
 829          */
 830         public function getNativeData( ) {
 831                 $text = $this->mText;
 832                 return $text;
 833         }
 834
 835         /**
 836          * Returns the text represented by this Content object, as a string.
 837          *
 838          * @param   the raw text
 839          */
 840         public function getTextForSearchIndex( ) {
 841                 return $this->getNativeData();
 842         }
 843
 844         /**
 845          * Returns the text represented by this Content object, as a string.
 846          *
 847          * @param   the raw text
 848          */
 849         public function getWikitextForTransclusion( ) {
 850                 return $this->getNativeData();
 851         }
 852
 853         /**
 854          * Diff this content object with another content object..
 855          *
 856          * @since WD.diff
 857          *
 858          * @param $that Content the other content object to compare this content object to
 859          * @param $lang Language the language object to use for text segmentation.
 860          *    If not given, $wgContentLang is used.
 861          *
 862          * @return DiffResult a diff representing the changes that would have to be
 863          *    made to this content object to make it equal to $that.
 864          */
 865         public function diff( Content $that, Language $lang = null ) {
 866                 global $wgContLang;
 867
 868                 $this->checkModelID( $that->getModel() );
 869
 870                 # @todo: could implement this in DifferenceEngine and just delegate here?
 871
 872                 if ( !$lang ) $lang = $wgContLang;
 873
 874                 $otext = $this->getNativeData();
 875                 $ntext = $this->getNativeData();
 876
 877                 # Note: Use native PHP diff, external engines don't give us abstract output
 878                 $ota = explode( "\n", $wgContLang->segmentForDiff( $otext ) );
 879                 $nta = explode( "\n", $wgContLang->segmentForDiff( $ntext ) );
 880
 881                 $diff = new Diff( $ota, $nta );
 882                 return $diff;
 883         }
 884
 885
 886         /**
 887          * Returns a generic ParserOutput object, wrapping the HTML returned by
 888          * getHtml().
 889          *
 890          * @param $title Title Context title for parsing
 891          * @param $revId int|null Revision ID (for {{REVISIONID}})
 892          * @param $options ParserOptions|null Parser options
 893          * @param $generateHtml bool Whether or not to generate HTML
 894          *
 895          * @return ParserOutput representing the HTML form of the text
 896          */
 897         public function getParserOutput( Title $title,
 898                 $revId = null,
 899                 ParserOptions $options = null, $generateHtml = true
 900         ) {
 901                 # Generic implementation, relying on $this->getHtml()
 902
 903                 if ( $generateHtml ) {
 904                         $html = $this->getHtml();
 905                 } else {
 906                         $html = '';
 907                 }
 908
 909                 $po = new ParserOutput( $html );
 910                 return $po;
 911         }
 912
 913         /**
 914          * Generates an HTML version of the content, for display. Used by
 915          * getParserOutput() to construct a ParserOutput object.
 916          *
 917          * This default implementation just calls getHighlightHtml(). Content
 918          * models that have another mapping to HTML (as is the case for markup
 919          * languages like wikitext) should override this method to generate the
 920          * appropriate HTML.
 921          *
 922          * @return string An HTML representation of the content
 923          */
 924         protected function getHtml() {
 925                 return $this->getHighlightHtml();
 926         }
 927
 928         /**
 929          * Generates a syntax-highlighted version of the content, as HTML.
 930          * Used by the default implementation of getHtml().
 931          *
 932          * @return string an HTML representation of the content's markup
 933          */
 934         protected function getHighlightHtml( ) {
 935                 # TODO: make Highlighter interface, use highlighter here, if available
 936                 return htmlspecialchars( $this->getNativeData() );
 937         }
 938
 939 }
 940
 941 /**
 942  * @since WD.1
 943  */
 944 class WikitextContent extends TextContent {
 945
 946         public function __construct( $text ) {
 947                 parent::__construct( $text, CONTENT_MODEL_WIKITEXT );
 948         }
 949
 950         /**
 951          * @see Content::getSection()
 952          */
 953         public function getSection( $section ) {
 954                 global $wgParser;
 955
 956                 $text = $this->getNativeData();
 957                 $sect = $wgParser->getSection( $text, $section, false );
 958
 959                 return  new WikitextContent( $sect );
 960         }
 961
 962         /**
 963          * @see Content::replaceSection()
 964          */
 965         public function replaceSection( $section, Content $with, $sectionTitle = '' ) {
 966                 wfProfileIn( __METHOD__ );
 967
 968                 $myModelId = $this->getModel();
 969                 $sectionModelId = $with->getModel();
 970
 971                 if ( $sectionModelId != $myModelId  ) {
 972                         throw new MWException( "Incompatible content model for section: " .
 973                                 "document uses $myModelId but " .
 974                                 "section uses $sectionModelId." );
 975                 }
 976
 977                 $oldtext = $this->getNativeData();
 978                 $text = $with->getNativeData();
 979
 980                 if ( $section === '' ) {
 981                         return $with; # XXX: copy first?
 982                 } if ( $section == 'new' ) {
 983                         # Inserting a new section
 984                         if ( $sectionTitle ) {
 985                                 $subject = wfMsgForContent( 'newsectionheaderdefaultlevel', $sectionTitle ) . "\n\n";
 986                         } else {
 987                                 $subject = '';
 988                         }
 989                         if ( wfRunHooks( 'PlaceNewSection', array( $this, $oldtext, $subject, &$text ) ) ) {
 990                                 $text = strlen( trim( $oldtext ) ) > 0
 991                                         ? "{$oldtext}\n\n{$subject}{$text}"
 992                                         : "{$subject}{$text}";
 993                         }
 994                 } else {
 995                         # Replacing an existing section; roll out the big guns
 996                         global $wgParser;
 997
 998                         $text = $wgParser->replaceSection( $oldtext, $section, $text );
 999                 }
1000
1001                 $newContent = new WikitextContent( $text );
1002
1003                 wfProfileOut( __METHOD__ );
1004                 return $newContent;
1005         }
1006
1007         /**
1008          * Returns a new WikitextContent object with the given section heading
1009          * prepended.
1010          *
1011          * @param $header string
1012          * @return Content
1013          */
1014         public function addSectionHeader( $header ) {
1015                 $text = wfMsgForContent( 'newsectionheaderdefaultlevel', $header ) . "\n\n" .
1016                         $this->getNativeData();
1017
1018                 return new WikitextContent( $text );
1019         }
1020
1021         /**
1022          * Returns a Content object with pre-save transformations applied using
1023          * Parser::preSaveTransform().
1024          *
1025          * @param $title Title
1026          * @param $user User
1027          * @param $popts ParserOptions
1028          * @return Content
1029          */
1030         public function preSaveTransform( Title $title, User $user, ParserOptions $popts ) {
1031                 global $wgParser;
1032
1033                 $text = $this->getNativeData();
1034                 $pst = $wgParser->preSaveTransform( $text, $title, $user, $popts );
1035
1036                 return new WikitextContent( $pst );
1037         }
1038
1039         /**
1040          * Returns a Content object with preload transformations applied (or this
1041          * object if no transformations apply).
1042          *
1043          * @param $title Title
1044          * @param $popts ParserOptions
1045          * @return Content
1046          */
1047         public function preloadTransform( Title $title, ParserOptions $popts ) {
1048                 global $wgParser;
1049
1050                 $text = $this->getNativeData();
1051                 $plt = $wgParser->getPreloadText( $text, $title, $popts );
1052
1053                 return new WikitextContent( $plt );
1054         }
1055
1056         /**
1057          * Implement redirect extraction for wikitext.
1058          *
1059          * @return null|Title
1060          *
1061          * @note: migrated here from Title::newFromRedirectInternal()
1062          *
1063          * @see Content::getRedirectTarget
1064          * @see AbstractContent::getRedirectTarget
1065          */
1066         public function getRedirectTarget() {
1067                 global $wgMaxRedirects;
1068                 if ( $wgMaxRedirects < 1 ) {
1069                         // redirects are disabled, so quit early
1070                         return null;
1071                 }
1072                 $redir = MagicWord::get( 'redirect' );
1073                 $text = trim( $this->getNativeData() );
1074                 if ( $redir->matchStartAndRemove( $text ) ) {
1075                         // Extract the first link and see if it's usable
1076                         // Ensure that it really does come directly after #REDIRECT
1077                         // Some older redirects included a colon, so don't freak about that!
1078                         $m = array();
1079                         if ( preg_match( '!^\s*:?\s*\[{2}(.*?)(?:\|.*?)?\]{2}!', $text, $m ) ) {
1080                                 // Strip preceding colon used to "escape" categories, etc.
1081                                 // and URL-decode links
1082                                 if ( strpos( $m[1], '%' ) !== false ) {
1083                                         // Match behavior of inline link parsing here;
1084                                         $m[1] = rawurldecode( ltrim( $m[1], ':' ) );
1085                                 }
1086                                 $title = Title::newFromText( $m[1] );
1087                                 // If the title is a redirect to bad special pages or is invalid, return null
1088                                 if ( !$title instanceof Title || !$title->isValidRedirectTarget() ) {
1089                                         return null;
1090                                 }
1091                                 return $title;
1092                         }
1093                 }
1094                 return null;
1095         }
1096
1097         /**
1098          * Returns true if this content is not a redirect, and this content's text
1099          * is countable according to the criteria defined by $wgArticleCountMethod.
1100          *
1101          * @param $hasLinks Bool  if it is known whether this content contains
1102          *    links, provide this information here, to avoid redundant parsing to
1103          *    find out.
1104          * @param $title null|\Title
1105          *
1106          * @internal param \IContextSource $context context for parsing if necessary
1107          *
1108          * @return bool True if the content is countable
1109          */
1110         public function isCountable( $hasLinks = null, Title $title = null ) {
1111                 global $wgArticleCountMethod;
1112
1113                 if ( $this->isRedirect( ) ) {
1114                         return false;
1115                 }
1116
1117                 $text = $this->getNativeData();
1118
1119                 switch ( $wgArticleCountMethod ) {
1120                         case 'any':
1121                                 return true;
1122                         case 'comma':
1123                                 return strpos( $text,  ',' ) !== false;
1124                         case 'link':
1125                                 if ( $hasLinks === null ) { # not known, find out
1126                                         if ( !$title ) {
1127                                                 $context = RequestContext::getMain();
1128                                                 $title = $context->getTitle();
1129                                         }
1130
1131                                         $po = $this->getParserOutput( $title, null, null, false );
1132                                         $links = $po->getLinks();
1133                                         $hasLinks = !empty( $links );
1134                                 }
1135
1136                                 return $hasLinks;
1137                 }
1138
1139                 return false;
1140         }
1141
1142         public function getTextForSummary( $maxlength = 250 ) {
1143                 $truncatedtext = parent::getTextForSummary( $maxlength );
1144
1145                 # clean up unfinished links
1146                 # XXX: make this optional? wasn't there in autosummary, but required for
1147                 # deletion summary.
1148                 $truncatedtext = preg_replace( '/\[\[([^\]]*)\]?$/', '$1', $truncatedtext );
1149
1150                 return $truncatedtext;
1151         }
1152
1153
1154         /**
1155          * Returns a ParserOutput object resulting from parsing the content's text
1156          * using $wgParser.
1157          *
1158          * @since    WD.1
1159          *
1160          * @param $content Content the content to render
1161          * @param $title \Title
1162          * @param $revId null
1163          * @param $options null|ParserOptions
1164          * @param $generateHtml bool
1165          *
1166          * @internal param \IContextSource|null $context
1167          * @return ParserOutput representing the HTML form of the text
1168          */
1169         public function getParserOutput( Title $title,
1170                 $revId = null,
1171                 ParserOptions $options = null, $generateHtml = true
1172         ) {
1173                 global $wgParser;
1174
1175                 if ( !$options ) {
1176                         $options = new ParserOptions();
1177                 }
1178
1179                 $po = $wgParser->parse( $this->getNativeData(), $title, $options, true, true, $revId );
1180                 return $po;
1181         }
1182
1183         protected function getHtml() {
1184                 throw new MWException(
1185                         "getHtml() not implemented for wikitext. "
1186                                 . "Use getParserOutput()->getText()."
1187                 );
1188         }
1189
1190
1191 }
1192
1193 /**
1194  * @since WD.1
1195  */
1196 class MessageContent extends TextContent {
1197         public function __construct( $msg_key, $params = null, $options = null ) {
1198                 # XXX: messages may be wikitext, html or plain text! and maybe even
1199                 # something else entirely.
1200                 parent::__construct( null, CONTENT_MODEL_WIKITEXT );
1201
1202                 $this->mMessageKey = $msg_key;
1203
1204                 $this->mParameters = $params;
1205
1206                 if ( is_null( $options ) ) {
1207                         $options = array();
1208                 }
1209                 elseif ( is_string( $options ) ) {
1210                         $options = array( $options );
1211                 }
1212
1213                 $this->mOptions = $options;
1214         }
1215
1216         /**
1217          * Returns the message as rendered HTML, using the options supplied to the
1218          * constructor plus "parse".
1219          * @param   the message text, parsed
1220          */
1221         public function getHtml(  ) {
1222                 $opt = array_merge( $this->mOptions, array( 'parse' ) );
1223
1224                 return wfMsgExt( $this->mMessageKey, $this->mParameters, $opt );
1225         }
1226
1227
1228         /**
1229          * Returns the message as raw text, using the options supplied to the
1230          * constructor minus "parse" and "parseinline".
1231          *
1232          * @param   the message text, unparsed.
1233          */
1234         public function getNativeData( ) {
1235                 $opt = array_diff( $this->mOptions, array( 'parse', 'parseinline' ) );
1236
1237                 return wfMsgExt( $this->mMessageKey, $this->mParameters, $opt );
1238         }
1239
1240 }
1241
1242 /**
1243  * @since WD.1
1244  */
1245 class JavaScriptContent extends TextContent {
1246         public function __construct( $text ) {
1247                 parent::__construct( $text, CONTENT_MODEL_JAVASCRIPT );
1248         }
1249
1250         /**
1251          * Returns a Content object with pre-save transformations applied using
1252          * Parser::preSaveTransform().
1253          *
1254          * @param Title $title
1255          * @param User $user
1256          * @param ParserOptions $popts
1257          * @return Content
1258          */
1259         public function preSaveTransform( Title $title, User $user, ParserOptions $popts ) {
1260                 global $wgParser;
1261                 // @todo: make pre-save transformation optional for script pages
1262                 // See bug #32858
1263
1264                 $text = $this->getNativeData();
1265                 $pst = $wgParser->preSaveTransform( $text, $title, $user, $popts );
1266
1267                 return new JavaScriptContent( $pst );
1268         }
1269
1270
1271         protected function getHtml( ) {
1272                 $html = "";
1273                 $html .= "<pre class=\"mw-code mw-js\" dir=\"ltr\">\n";
1274                 $html .= $this->getHighlightHtml( );
1275                 $html .= "\n</pre>\n";
1276
1277                 return $html;
1278         }
1279 }
1280
1281 /**
1282  * @since WD.1
1283  */
1284 class CssContent extends TextContent {
1285         public function __construct( $text ) {
1286                 parent::__construct( $text, CONTENT_MODEL_CSS );
1287         }
1288
1289         /**
1290          * Returns a Content object with pre-save transformations applied using
1291          * Parser::preSaveTransform().
1292          *
1293          * @param $title Title
1294          * @param $user User
1295          * @param $popts ParserOptions
1296          * @return Content
1297          */
1298         public function preSaveTransform( Title $title, User $user, ParserOptions $popts ) {
1299                 global $wgParser;
1300                 // @todo: make pre-save transformation optional for script pages
1301
1302                 $text = $this->getNativeData();
1303                 $pst = $wgParser->preSaveTransform( $text, $title, $user, $popts );
1304
1305                 return new CssContent( $pst );
1306         }
1307
1308
1309         protected function getHtml( ) {
1310                 $html = "";
1311                 $html .= "<pre class=\"mw-code mw-css\" dir=\"ltr\">\n";
1312                 $html .= $this->getHighlightHtml( );
1313                 $html .= "\n</pre>\n";
1314
1315                 return $html;
1316         }
1317 }