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 building a full text search index.
  14          *         If no useful representation exists, this method returns an empty string.
  15          *
  16          * @todo: test that this actually works
  17          * @todo: make sure this also works with LuceneSearch / WikiSearch
  18          */
  19         public function getTextForSearchIndex( );
  20
  21         /**
  22          * @since WD.1
  23          *
  24          * @return String the wikitext to include when another page includes this  content, or false if the content is not
  25          *         includable in a wikitext page.
  26          *
  27          * @TODO: allow native handling, bypassing wikitext representation, like for includable special pages.
  28          * @TODO: allow transclusion into other content models than Wikitext!
  29          * @TODO: used in WikiPage and MessageCache to get message text. Not so nice. What should we use instead?!
  30          */
  31         public function getWikitextForTransclusion( );
  32
  33         /**
  34          * Returns a textual representation of the content suitable for use in edit summaries and log messages.
  35          *
  36          * @since WD.1
  37          *
  38          * @param int $maxlength maximum length of the summary text
  39          * @return String the summary text
  40          */
  41         public function getTextForSummary( $maxlength = 250 );
  42
  43         /**
  44          * Returns native representation of the data. Interpretation depends on the data model used,
  45          * as given by getDataModel().
  46          *
  47          * @since WD.1
  48          *
  49          * @return mixed the native representation of the content. Could be a string, a nested array
  50          *         structure, an object, a binary blob... anything, really.
  51          *
  52          * @NOTE: review all calls carefully, caller must be aware of content model!
  53          */
  54         public function getNativeData( );
  55
  56         /**
  57          * returns the content's nominal size in bogo-bytes.
  58          *
  59          * @return int
  60          */
  61         public function getSize( );
  62
  63         /**
  64          * Returns the id of the content model used by this content objects.
  65          * Corresponds to the CONTENT_MODEL_XXX constants.
  66          *
  67          * @since WD.1
  68          *
  69          * @return int the model id
  70          */
  71         public function getModel();
  72
  73         /**
  74          * Convenience method that returns the ContentHandler singleton for handling the content
  75          * model this Content object uses.
  76          *
  77          * Shorthand for ContentHandler::getForContent( $this )
  78          *
  79          * @since WD.1
  80          *
  81          * @return ContentHandler
  82          */
  83         public function getContentHandler();
  84
  85         /**
  86          * Convenience method that returns the default serialization format for the content model
  87          * model this Content object uses.
  88          *
  89          * Shorthand for $this->getContentHandler()->getDefaultFormat()
  90          *
  91          * @since WD.1
  92          *
  93          * @return ContentHandler
  94          */
  95         public function getDefaultFormat();
  96
  97         /**
  98          * Convenience method that returns the list of serialization formats supported
  99          * for the content model model this Content object uses.
 100          *
 101          * Shorthand for $this->getContentHandler()->getSupportedFormats()
 102          *
 103          * @since WD.1
 104          *
 105          * @return array of supported serialization formats
 106          */
 107         public function getSupportedFormats();
 108
 109         /**
 110          * Returns true if $format is a supported serialization format for this Content object,
 111          * false if it isn't.
 112          *
 113          * Note that this should always return true if $format is null, because null stands for the
 114          * default serialization.
 115          *
 116          * Shorthand for $this->getContentHandler()->isSupportedFormat( $format )
 117          *
 118          * @since WD.1
 119          *
 120          * @param String $format the format to check
 121          * @return bool whether the format is supported
 122          */
 123         public function isSupportedFormat( $format );
 124
 125         /**
 126          * Convenience method for serializing this Content object.
 127          *
 128          * Shorthand for $this->getContentHandler()->serializeContent( $this, $format )
 129          *
 130          * @since WD.1
 131          *
 132          * @param null|String $format the desired serialization format (or null for the default format).
 133          * @return String serialized form of this Content object
 134          */
 135         public function serialize( $format = null );
 136
 137         /**
 138          * Returns true if this Content object represents empty content.
 139          *
 140          * @since WD.1
 141          *
 142          * @return bool whether this Content object is empty
 143          */
 144         public function isEmpty();
 145
 146         /**
 147          * Returns whether the content is valid. This is intended for local validity checks, not considering global consistency.
 148          * Content needs to be valid before it can be saved.
 149          *
 150          * This default implementation always returns true.
 151          *
 152          * @since WD.1
 153          *
 154          * @return boolean
 155          */
 156         public function isValid();
 157
 158         /**
 159          * Returns true if this Content objects is conceptually equivalent to the given Content object.
 160          * Contract:
 161          *
 162          * * Will return false if $that is null.
 163          * * Will return true if $that === $this.
 164          * * Will return false if $that->getModelName() != $this->getModel().
 165          * * Will return false if $that->getNativeData() is not equal to $this->getNativeData(),
 166          *   where the meaning of "equal" depends on the actual data model.
 167          *
 168          * Implementations should be careful to make equals() transitive and reflexive:
 169          *
 170          * * $a->equals( $b ) <=> $b->equals( $a )
 171          * * $a->equals( $b ) &&  $b->equals( $c ) ==> $a->equals( $c )
 172          *
 173          * @since WD.1
 174          *
 175          * @param Content $that the Content object to compare to
 176          * @return bool true if this Content object is equal to $that, false otherwise.
 177          */
 178         public function equals( Content $that = null );
 179
 180         /**
 181          * Return a copy of this Content object. The following must be true for the object returned
 182          * if $copy = $original->copy()
 183          *
 184          * * get_class($original) === get_class($copy)
 185          * * $original->getModel() === $copy->getModel()
 186          * * $original->equals( $copy )
 187          *
 188          * If and only if the Content object is immutable, the copy() method can and should
 189          * return $this. That is,  $copy === $original may be true, but only for immutable content
 190          * objects.
 191          *
 192          * @since WD.1
 193          *
 194          * @return Content. A copy of this object
 195          */
 196         public function copy( );
 197
 198         /**
 199          * Returns true if this content is countable as a "real" wiki page, provided
 200          * that it's also in a countable location (e.g. a current revision in the main namespace).
 201          *
 202          * @since WD.1
 203          *
 204          * @param $hasLinks Bool: if it is known whether this content contains links, provide this information here,
 205          *                        to avoid redundant parsing to find out.
 206          * @return boolean
 207          */
 208         public function isCountable( $hasLinks = null ) ;
 209
 210         /**
 211          * Convenience method, shorthand for
 212          * $this->getContentHandler()->getParserOutput( $this, $title, $revId, $options, $generateHtml )
 213          *
 214          * @note: subclasses should NOT override this to provide custom rendering.
 215          *        Override ContentHandler::getParserOutput() instead!
 216          *
 217          * @param Title $title
 218          * @param null $revId
 219          * @param null|ParserOptions $options
 220          * @param Boolean $generateHtml whether to generate Html (default: true). If false,
 221          *        the result of calling getText() on the ParserOutput object returned by
 222          *        this method is undefined.
 223          *
 224          * @since WD.1
 225          *
 226          * @return ParserOutput
 227          */
 228         public function getParserOutput( Title $title, $revId = null, ParserOptions $options = null, $generateHtml = true );
 229
 230         /**
 231          * Construct the redirect destination from this content and return an
 232          * array of Titles, or null if this content doesn't represent a redirect.
 233          * The last element in the array is the final destination after all redirects
 234          * have been resolved (up to $wgMaxRedirects times).
 235          *
 236          * @since WD.1
 237          *
 238          * @return Array of Titles, with the destination last
 239          */
 240         public function getRedirectChain();
 241
 242         /**
 243          * Construct the redirect destination from this content and return a Title,
 244          * or null if this content doesn't represent a redirect.
 245          * This will only return the immediate redirect target, useful for
 246          * the redirect table and other checks that don't need full recursion.
 247          *
 248          * @since WD.1
 249          *
 250          * @return Title: The corresponding Title
 251          */
 252         public function getRedirectTarget();
 253
 254         /**
 255          * Construct the redirect destination from this content and return the
 256          * Title, or null if this content doesn't represent a redirect.
 257          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 258          * in order to provide (hopefully) the Title of the final destination instead of another redirect.
 259          *
 260          * @since WD.1
 261          *
 262          * @return Title
 263          */
 264         public function getUltimateRedirectTarget();
 265
 266         /**
 267          * Returns whether this Content represents a redirect.
 268          * Shorthand for getRedirectTarget() !== null.
 269          *
 270          * @since WD.1
 271          *
 272          * @return bool
 273          */
 274         public function isRedirect();
 275
 276         /**
 277          * Returns the section with the given id.
 278          *
 279          * @since WD.1
 280          *
 281          * @param String $sectionId the section's id, given as a numeric string. The id "0" retrieves the section before
 282          *          the first heading, "1" the text between the first heading (included) and the second heading (excluded), etc.
 283          * @return Content|Boolean|null the section, or false if no such section exist, or null if sections are not supported
 284          */
 285         public function getSection( $sectionId );
 286
 287         /**
 288          * Replaces a section of the content and returns a Content object with the section replaced.
 289          *
 290          * @since WD.1
 291          *
 292          * @param $section empty/null/false or a section number (0, 1, 2, T1, T2...), or "new"
 293          * @param $with Content: new content of the section
 294          * @param $sectionTitle String: new section's subject, only if $section is 'new'
 295          * @return string Complete article text, or null if error
 296          */
 297         public function replaceSection( $section, Content $with, $sectionTitle = ''  );
 298
 299         /**
 300          * Returns a Content object with pre-save transformations applied (or this object if no transformations apply).
 301          *
 302          * @since WD.1
 303          *
 304          * @param Title $title
 305          * @param User $user
 306          * @param null|ParserOptions $popts
 307          * @return Content
 308          */
 309         public function preSaveTransform( Title $title, User $user, ParserOptions $popts );
 310
 311         /**
 312          * Returns a new WikitextContent object with the given section heading prepended, if supported.
 313          * The default implementation just returns this Content object unmodified, ignoring the section header.
 314          *
 315          * @since WD.1
 316          *
 317          * @param $header String
 318          * @return Content
 319          */
 320         public function addSectionHeader( $header );
 321
 322         /**
 323          * Returns a Content object with preload transformations applied (or this object if no transformations apply).
 324          *
 325          * @since WD.1
 326          *
 327          * @param Title $title
 328          * @param null|ParserOptions $popts
 329          * @return Content
 330          */
 331         public function preloadTransform( Title $title, ParserOptions $popts );
 332
 333         # TODO: handle ImagePage and CategoryPage
 334         # TODO: make sure we cover lucene search / wikisearch.
 335         # TODO: make sure ReplaceTemplates still works
 336         # FUTURE: nice&sane integration of GeSHi syntax highlighting
 337         #   [11:59] <vvv> Hooks are ugly; make CodeHighlighter interface and a config to set the class which handles syntax highlighting
 338         #   [12:00] <vvv> And default it to a DummyHighlighter
 339
 340         # TODO: make sure we cover the external editor interface (does anyone actually use that?!)
 341
 342         # TODO: tie into API to provide contentModel for Revisions
 343         # TODO: tie into API to provide serialized version and contentFormat for Revisions
 344         # TODO: tie into API edit interface
 345         # FUTURE: make EditForm plugin for EditPage
 346
 347         # FUTURE: special type for redirects?!
 348         # FUTURE: MultipartMultipart < WikipageContent (Main + Links + X)
 349         # FUTURE: LinksContent < LanguageLinksContent, CategoriesContent
 350
 351 // @TODO: add support for ar_content_format, ar_content_model, rev_content_format, rev_content_model to API
 352 }
 353
 354
 355 /**
 356  * A content object represents page content, e.g. the text to show on a page.
 357  * Content objects have no knowledge about how they relate to Wiki pages.
 358  *
 359  * @since 1.WD
 360  */
 361 abstract class AbstractContent implements Content {
 362
 363         /**
 364          * Name of the content model this Content object represents.
 365          * Use with CONTENT_MODEL_XXX constants
 366          *
 367          * @var String $model_id
 368          */
 369         protected $model_id;
 370
 371         /**
 372          * @param int $model_id
 373          */
 374         public function __construct( $model_id = null ) {
 375                 $this->model_id = $model_id;
 376         }
 377
 378         /**
 379          * Returns the id of the content model used by this content objects.
 380          * Corresponds to the CONTENT_MODEL_XXX constants.
 381          *
 382          * @since WD.1
 383          *
 384          * @return int the model id
 385          */
 386         public function getModel() {
 387                 return $this->model_id;
 388         }
 389
 390         /**
 391          * Throws an MWException if $model_id is not the id of the content model
 392          * supported by this Content object.
 393          *
 394          * @param int $model_id the model to check
 395          *
 396          * @throws MWException
 397          */
 398         protected function checkModelID( $model_id ) {
 399                 if ( $model_id !== $this->model_id ) {
 400                         $model_name = ContentHandler::getContentModelName( $model_id );
 401                         $own_model_name = ContentHandler::getContentModelName( $this->model_id );
 402
 403                         throw new MWException( "Bad content model: expected {$this->model_id} ($own_model_name) but got found $model_id ($model_name)." );
 404                 }
 405         }
 406
 407         /**
 408          * Convenience method that returns the ContentHandler singleton for handling the content
 409          * model this Content object uses.
 410          *
 411          * Shorthand for ContentHandler::getForContent( $this )
 412          *
 413          * @since WD.1
 414          *
 415          * @return ContentHandler
 416          */
 417         public function getContentHandler() {
 418                 return ContentHandler::getForContent( $this );
 419         }
 420
 421         /**
 422          * Convenience method that returns the default serialization format for the content model
 423          * model this Content object uses.
 424          *
 425          * Shorthand for $this->getContentHandler()->getDefaultFormat()
 426          *
 427          * @since WD.1
 428          *
 429          * @return ContentHandler
 430          */
 431         public function getDefaultFormat() {
 432                 return $this->getContentHandler()->getDefaultFormat();
 433         }
 434
 435         /**
 436          * Convenience method that returns the list of serialization formats supported
 437          * for the content model model this Content object uses.
 438          *
 439          * Shorthand for $this->getContentHandler()->getSupportedFormats()
 440          *
 441          * @since WD.1
 442          *
 443          * @return array of supported serialization formats
 444          */
 445         public function getSupportedFormats() {
 446                 return $this->getContentHandler()->getSupportedFormats();
 447         }
 448
 449         /**
 450          * Returns true if $format is a supported serialization format for this Content object,
 451          * false if it isn't.
 452          *
 453          * Note that this will always return true if $format is null, because null stands for the
 454          * default serialization.
 455          *
 456          * Shorthand for $this->getContentHandler()->isSupportedFormat( $format )
 457          *
 458          * @since WD.1
 459          *
 460          * @param String $format the format to check
 461          * @return bool whether the format is supported
 462          */
 463         public function isSupportedFormat( $format ) {
 464                 if ( !$format ) {
 465                         return true; // this means "use the default"
 466                 }
 467
 468                 return $this->getContentHandler()->isSupportedFormat( $format );
 469         }
 470
 471         /**
 472          * Throws an MWException if $this->isSupportedFormat( $format ) doesn't return true.
 473          *
 474          * @param $format
 475          * @throws MWException
 476          */
 477         protected function checkFormat( $format ) {
 478                 if ( !$this->isSupportedFormat( $format ) ) {
 479                         throw new MWException( "Format $format is not supported for content model " . $this->getModel() );
 480                 }
 481         }
 482
 483         /**
 484          * Convenience method for serializing this Content object.
 485          *
 486          * Shorthand for $this->getContentHandler()->serializeContent( $this, $format )
 487          *
 488          * @since WD.1
 489          *
 490          * @param null|String $format the desired serialization format (or null for the default format).
 491          * @return String serialized form of this Content object
 492          */
 493         public function serialize( $format = null ) {
 494                 return $this->getContentHandler()->serializeContent( $this, $format );
 495         }
 496
 497         /**
 498          * Returns true if this Content object represents empty content.
 499          *
 500          * @since WD.1
 501          *
 502          * @return bool whether this Content object is empty
 503          */
 504         public function isEmpty() {
 505                 return $this->getSize() == 0;
 506         }
 507
 508         /**
 509          * Returns if the content is valid. This is intended for local validity checks, not considering global consistency.
 510          * It needs to be valid before it can be saved.
 511          *
 512          * This default implementation always returns true.
 513          *
 514          * @since WD.1
 515          *
 516          * @return boolean
 517          */
 518         public function isValid() {
 519                 return true;
 520         }
 521
 522         /**
 523          * Returns true if this Content objects is conceptually equivalent to the given Content object.
 524          *
 525          * Will returns false if $that is null.
 526          * Will return true if $that === $this.
 527          * Will return false if $that->getModelName() != $this->getModel().
 528          * Will return false if $that->getNativeData() is not equal to $this->getNativeData(),
 529          * where the meaning of "equal" depends on the actual data model.
 530          *
 531          * Implementations should be careful to make equals() transitive and reflexive:
 532          *
 533          * * $a->equals( $b ) <=> $b->equals( $a )
 534          * * $a->equals( $b ) &&  $b->equals( $c ) ==> $a->equals( $c )
 535          *
 536          * @since WD.1
 537          *
 538          * @param Content $that the Content object to compare to
 539          * @return bool true if this Content object is euqual to $that, false otherwise.
 540          */
 541         public function equals( Content $that = null ) {
 542                 if ( is_null( $that ) ){
 543                         return false;
 544                 }
 545
 546                 if ( $that === $this ) {
 547                         return true;
 548                 }
 549
 550                 if ( $that->getModel() !== $this->getModel() ) {
 551                         return false;
 552                 }
 553
 554                 return $this->getNativeData() === $that->getNativeData();
 555         }
 556
 557         /**
 558          * Convenience method, shorthand for
 559          * $this->getContentHandler()->getParserOutput( $this, $title, $revId, $options, $generateHtml )
 560          *
 561          * @note: subclasses should NOT override this to provide custom rendering.
 562          *        Override ContentHandler::getParserOutput() instead!
 563          *
 564          * @param Title $title
 565          * @param null $revId
 566          * @param null|ParserOptions $options
 567          * @param Boolean $generateHtml whether to generate Html (default: true). If false,
 568          *        the result of calling getText() on the ParserOutput object returned by
 569          *        this method is undefined.
 570          *
 571          * @since WD.1
 572          *
 573          * @return ParserOutput
 574          */
 575         public function getParserOutput( Title $title, $revId = null, ParserOptions $options = null, $generateHtml = true ) {
 576                 return $this->getContentHandler()->getParserOutput( $this, $title, $revId, $options, $generateHtml );
 577         }
 578
 579         /**
 580          * Construct the redirect destination from this content and return an
 581          * array of Titles, or null if this content doesn't represent a redirect.
 582          * The last element in the array is the final destination after all redirects
 583          * have been resolved (up to $wgMaxRedirects times).
 584          *
 585          * @since WD.1
 586          *
 587          * @return Array of Titles, with the destination last
 588          */
 589         public function getRedirectChain() {
 590                 return null;
 591         }
 592
 593         /**
 594          * Construct the redirect destination from this content and return a Title,
 595          * or null if this content doesn't represent a redirect.
 596          * This will only return the immediate redirect target, useful for
 597          * the redirect table and other checks that don't need full recursion.
 598          *
 599          * @since WD.1
 600          *
 601          * @return Title: The corresponding Title
 602          */
 603         public function getRedirectTarget() {
 604                 return null;
 605         }
 606
 607         /**
 608          * Construct the redirect destination from this content and return the
 609          * Title, or null if this content doesn't represent a redirect.
 610          * This will recurse down $wgMaxRedirects times or until a non-redirect target is hit
 611          * in order to provide (hopefully) the Title of the final destination instead of another redirect.
 612          *
 613          * @since WD.1
 614          *
 615          * @return Title
 616          */
 617         public function getUltimateRedirectTarget() {
 618                 return null;
 619         }
 620
 621         /**
 622          * @since WD.1
 623          *
 624          * @return bool
 625          */
 626         public function isRedirect() {
 627                 return $this->getRedirectTarget() !== null;
 628         }
 629
 630         /**
 631          * Returns the section with the given id.
 632          *
 633          * The default implementation returns null.
 634          *
 635          * @since WD.1
 636          *
 637          * @param String $sectionId the section's id, given as a numeric string. The id "0" retrieves the section before
 638          *          the first heading, "1" the text between the first heading (included) and the second heading (excluded), etc.
 639          * @return Content|Boolean|null the section, or false if no such section exist, or null if sections are not supported
 640          */
 641         public function getSection( $sectionId ) {
 642                 return null;
 643         }
 644
 645         /**
 646          * Replaces a section of the content and returns a Content object with the section replaced.
 647          *
 648          * @since WD.1
 649          *
 650          * @param $section empty/null/false or a section number (0, 1, 2, T1, T2...), or "new"
 651          * @param $with Content: new content of the section
 652          * @param $sectionTitle String: new section's subject, only if $section is 'new'
 653          * @return string Complete article text, or null if error
 654          */
 655         public function replaceSection( $section, Content $with, $sectionTitle = ''  ) {
 656                 return null;
 657         }
 658
 659         /**
 660          * Returns a Content object with pre-save transformations applied (or this object if no transformations apply).
 661          *
 662          * @since WD.1
 663          *
 664          * @param Title $title
 665          * @param User $user
 666          * @param null|ParserOptions $popts
 667          * @return Content
 668          */
 669         public function preSaveTransform( Title $title, User $user, ParserOptions $popts ) {
 670                 return $this;
 671         }
 672
 673         /**
 674          * Returns a new WikitextContent object with the given section heading prepended, if supported.
 675          * The default implementation just returns this Content object unmodified, ignoring the section header.
 676          *
 677          * @since WD.1
 678          *
 679          * @param $header String
 680          * @return Content
 681          */
 682         public function addSectionHeader( $header ) {
 683                 return $this;
 684         }
 685
 686         /**
 687          * Returns a Content object with preload transformations applied (or this object if no transformations apply).
 688          *
 689          * @since WD.1
 690          *
 691          * @param Title $title
 692          * @param null|ParserOptions $popts
 693          * @return Content
 694          */
 695         public function preloadTransform( Title $title, ParserOptions $popts ) {
 696                 return $this;
 697         }
 698 }
 699
 700 /**
 701  * Content object implementation for representing flat text.
 702  *
 703  * TextContent instances are immutable
 704  *
 705  * @since WD.1
 706  */
 707 abstract class TextContent extends AbstractContent {
 708
 709         public function __construct( $text, $model_id = null ) {
 710                 parent::__construct( $model_id );
 711
 712                 $this->mText = $text;
 713         }
 714
 715         public function copy() {
 716                 return $this; #NOTE: this is ok since TextContent are immutable.
 717         }
 718
 719         public function getTextForSummary( $maxlength = 250 ) {
 720                 global $wgContLang;
 721
 722                 $text = $this->getNativeData();
 723
 724                 $truncatedtext = $wgContLang->truncate(
 725                         preg_replace( "/[\n\r]/", ' ', $text ),
 726                         max( 0, $maxlength ) );
 727
 728                 return $truncatedtext;
 729         }
 730
 731         /**
 732          * returns the text's size in bytes.
 733          *
 734          * @return int the size
 735          */
 736         public function getSize( ) {
 737                 $text = $this->getNativeData( );
 738                 return strlen( $text );
 739         }
 740
 741         /**
 742          * Returns true if this content is not a redirect, and $wgArticleCountMethod is "any".
 743          *
 744          * @param $hasLinks Bool: if it is known whether this content contains links, provide this information here,
 745          *                        to avoid redundant parsing to find out.
 746          *
 747          * @return bool true if the content is countable
 748          */
 749         public function isCountable( $hasLinks = null ) {
 750                 global $wgArticleCountMethod;
 751
 752                 if ( $this->isRedirect( ) ) {
 753                         return false;
 754                 }
 755
 756                 if (  $wgArticleCountMethod === 'any' ) {
 757                         return true;
 758                 }
 759
 760                 return false;
 761         }
 762
 763         /**
 764          * Returns the text represented by this Content object, as a string.
 765          *
 766          * @return String the raw text
 767          */
 768         public function getNativeData( ) {
 769                 $text = $this->mText;
 770                 return $text;
 771         }
 772
 773         /**
 774          * Returns the text represented by this Content object, as a string.
 775          *
 776          * @return String the raw text
 777          */
 778         public function getTextForSearchIndex( ) {
 779                 return $this->getNativeData();
 780         }
 781
 782         /**
 783          * Returns the text represented by this Content object, as a string.
 784          *
 785          * @return String the raw text
 786          */
 787         public function getWikitextForTransclusion( ) {
 788                 return $this->getNativeData();
 789         }
 790
 791         /**
 792          * Diff this content object with another content object..
 793          *
 794          * @since WD.diff
 795          *
 796          * @param Content $that the other content object to compare this content object to
 797          * @param Language $lang the language object to use for text segmentation. If not given, $wgContentLang is used.
 798          *
 799          * @return DiffResult a diff representing the changes that would have to be made to this content object
 800          *         to make it equal to $that.
 801          */
 802         public function diff( Content $that, Language $lang = null ) {
 803                 global $wgContLang;
 804
 805                 $this->checkModelID( $that->getModel() );
 806
 807                 #@todo: could implement this in DifferenceEngine and just delegate here?
 808
 809                 if ( !$lang ) $lang = $wgContLang;
 810
 811                 $otext = $this->getNativeData();
 812                 $ntext = $this->getNativeData();
 813
 814                 # Note: Use native PHP diff, external engines don't give us abstract output
 815                 $ota = explode( "\n", $wgContLang->segmentForDiff( $otext ) );
 816                 $nta = explode( "\n", $wgContLang->segmentForDiff( $ntext ) );
 817
 818                 $diff = new Diff( $ota, $nta );
 819                 return $diff;
 820         }
 821
 822
 823 }
 824
 825 /**
 826  * @since WD.1
 827  */
 828 class WikitextContent extends TextContent {
 829
 830         public function __construct( $text ) {
 831                 parent::__construct($text, CONTENT_MODEL_WIKITEXT);
 832         }
 833
 834         /**
 835          * Returns the section with the given id.
 836          *
 837          * @param String $section
 838          *
 839          * @internal param String $sectionId the section's id
 840          * @return Content|false|null the section, or false if no such section exist, or null if sections are not supported
 841          */
 842         public function getSection( $section ) {
 843                 global $wgParser;
 844
 845                 $text = $this->getNativeData();
 846                 $sect = $wgParser->getSection( $text, $section, false );
 847
 848                 return  new WikitextContent( $sect );
 849         }
 850
 851         /**
 852          * Replaces a section in the wikitext
 853          *
 854          * @param $section      empty/null/false or a section number (0, 1, 2, T1, T2...), or "new"
 855          * @param $with         Content: new content of the section
 856          * @param $sectionTitle String: new section's subject, only if $section is 'new'
 857          *
 858          * @throws MWException
 859          * @return Content Complete article content, or null if error
 860          */
 861         public function replaceSection( $section, Content $with, $sectionTitle = '' ) {
 862                 wfProfileIn( __METHOD__ );
 863
 864                 $myModelId = $this->getModel();
 865                 $sectionModelId = $with->getModel();
 866
 867                 if ( $sectionModelId != $myModelId  ) {
 868                         $myModelName = ContentHandler::getContentModelName( $myModelId );
 869                         $sectionModelName = ContentHandler::getContentModelName( $sectionModelId );
 870
 871                         throw new MWException( "Incompatible content model for section: document uses $myModelId ($myModelName), "
 872                                                                 . "section uses $sectionModelId ($sectionModelName)." );
 873                 }
 874
 875                 $oldtext = $this->getNativeData();
 876                 $text = $with->getNativeData();
 877
 878                 if ( $section === '' ) {
 879                         return $with; #XXX: copy first?
 880                 } if ( $section == 'new' ) {
 881                         # Inserting a new section
 882                         $subject = $sectionTitle ? wfMsgForContent( 'newsectionheaderdefaultlevel', $sectionTitle ) . "\n\n" : '';
 883                         if ( wfRunHooks( 'PlaceNewSection', array( $this, $oldtext, $subject, &$text ) ) ) {
 884                                 $text = strlen( trim( $oldtext ) ) > 0
 885                                         ? "{$oldtext}\n\n{$subject}{$text}"
 886                                         : "{$subject}{$text}";
 887                         }
 888                 } else {
 889                         # Replacing an existing section; roll out the big guns
 890                         global $wgParser;
 891
 892                         $text = $wgParser->replaceSection( $oldtext, $section, $text );
 893                 }
 894
 895                 $newContent = new WikitextContent( $text );
 896
 897                 wfProfileOut( __METHOD__ );
 898                 return $newContent;
 899         }
 900
 901         /**
 902          * Returns a new WikitextContent object with the given section heading prepended.
 903          *
 904          * @param $header String
 905          * @return Content
 906          */
 907         public function addSectionHeader( $header ) {
 908                 $text = wfMsgForContent( 'newsectionheaderdefaultlevel', $header ) . "\n\n" . $this->getNativeData();
 909
 910                 return new WikitextContent( $text );
 911         }
 912
 913         /**
 914          * Returns a Content object with pre-save transformations applied (or this object if no transformations apply).
 915          *
 916          * @param Title $title
 917          * @param User $user
 918          * @param ParserOptions $popts
 919          * @return Content
 920          */
 921         public function preSaveTransform( Title $title, User $user, ParserOptions $popts ) { #FIXME: also needed for JS/CSS!
 922                 global $wgParser, $wgConteLang;
 923
 924                 $text = $this->getNativeData();
 925                 $pst = $wgParser->preSaveTransform( $text, $title, $user, $popts );
 926
 927                 return new WikitextContent( $pst );
 928         }
 929
 930         /**
 931          * Returns a Content object with preload transformations applied (or this object if no transformations apply).
 932          *
 933          * @param Title $title
 934          * @param ParserOptions $popts
 935          * @return Content
 936          */
 937         public function preloadTransform( Title $title, ParserOptions $popts ) {
 938                 global $wgParser, $wgConteLang;
 939
 940                 $text = $this->getNativeData();
 941                 $plt = $wgParser->getPreloadText( $text, $title, $popts );
 942
 943                 return new WikitextContent( $plt );
 944         }
 945
 946         public function getRedirectChain() {
 947                 $text = $this->getNativeData();
 948                 return Title::newFromRedirectArray( $text );
 949         }
 950
 951         public function getRedirectTarget() {
 952                 $text = $this->getNativeData();
 953                 return Title::newFromRedirect( $text );
 954         }
 955
 956         public function getUltimateRedirectTarget() {
 957                 $text = $this->getNativeData();
 958                 return Title::newFromRedirectRecurse( $text );
 959         }
 960
 961         /**
 962          * Returns true if this content is not a redirect, and this content's text is countable according to
 963          * the criteria defined by $wgArticleCountMethod.
 964          *
 965          * @param Bool        $hasLinks  if it is known whether this content contains links, provide this information here,
 966          *                               to avoid redundant parsing to find out.
 967          * @param null|\Title $title
 968          *
 969          * @internal param \IContextSource $context context for parsing if necessary
 970          *
 971          * @return bool true if the content is countable
 972          */
 973         public function isCountable( $hasLinks = null, Title $title = null ) {
 974                 global $wgArticleCountMethod, $wgRequest;
 975
 976                 if ( $this->isRedirect( ) ) {
 977                         return false;
 978                 }
 979
 980                 $text = $this->getNativeData();
 981
 982                 switch ( $wgArticleCountMethod ) {
 983                         case 'any':
 984                                 return true;
 985                         case 'comma':
 986                                 return strpos( $text,  ',' ) !== false;
 987                         case 'link':
 988                                 if ( $hasLinks === null ) { # not known, find out
 989                                         if ( !$title ) {
 990                                                 $context = RequestContext::getMain();
 991                                                 $title = $context->getTitle();
 992                                         }
 993
 994                                         $po = $this->getParserOutput( $title, null, null, false );
 995                                         $links = $po->getLinks();
 996                                         $hasLinks = !empty( $links );
 997                                 }
 998
 999                                 return $hasLinks;
1000                 }
1001
1002                 return false;
1003         }
1004
1005         public function getTextForSummary( $maxlength = 250 ) {
1006                 $truncatedtext = parent::getTextForSummary( $maxlength );
1007
1008                 #clean up unfinished links
1009                 #XXX: make this optional? wasn't there in autosummary, but required for deletion summary.
1010                 $truncatedtext = preg_replace( '/\[\[([^\]]*)\]?$/', '$1', $truncatedtext );
1011
1012                 return $truncatedtext;
1013         }
1014
1015 }
1016
1017 /**
1018  * @since WD.1
1019  */
1020 class MessageContent extends TextContent {
1021         public function __construct( $msg_key, $params = null, $options = null ) {
1022                 parent::__construct(null, CONTENT_MODEL_WIKITEXT); #XXX: messages may be wikitext, html or plain text! and maybe even something else entirely.
1023
1024                 $this->mMessageKey = $msg_key;
1025
1026                 $this->mParameters = $params;
1027
1028                 if ( is_null( $options ) ) {
1029                         $options = array();
1030                 }
1031                 elseif ( is_string( $options ) ) {
1032                         $options = array( $options );
1033                 }
1034
1035                 $this->mOptions = $options;
1036         }
1037
1038         /**
1039          * Returns the message as rendered HTML, using the options supplied to the constructor plus "parse".
1040          * @return String the message text, parsed
1041          */
1042         public function getHtml(  ) {
1043                 $opt = array_merge( $this->mOptions, array('parse') );
1044
1045                 return wfMsgExt( $this->mMessageKey, $this->mParameters, $opt );
1046         }
1047
1048
1049         /**
1050          * Returns the message as raw text, using the options supplied to the constructor minus "parse" and "parseinline".
1051          *
1052          * @return String the message text, unparsed.
1053          */
1054         public function getNativeData( ) {
1055                 $opt = array_diff( $this->mOptions, array('parse', 'parseinline') );
1056
1057                 return wfMsgExt( $this->mMessageKey, $this->mParameters, $opt );
1058         }
1059
1060 }
1061
1062 /**
1063  * @since WD.1
1064  */
1065 class JavaScriptContent extends TextContent {
1066         public function __construct( $text ) {
1067                 parent::__construct($text, CONTENT_MODEL_JAVASCRIPT);
1068         }
1069
1070 }
1071
1072 /**
1073  * @since WD.1
1074  */
1075 class CssContent extends TextContent {
1076         public function __construct( $text ) {
1077                 parent::__construct($text, CONTENT_MODEL_CSS);
1078         }
1079 }