includes/Pager.php

   1 <?php
   2 /**
   3  * @defgroup Pager Pager
   4  *
   5  * @file
   6  * @ingroup Pager
   7  */
   8
   9 /**
  10  * Basic pager interface.
  11  * @ingroup Pager
  12  */
  13 interface Pager {
  14         function getNavigationBar();
  15         function getBody();
  16 }
  17
  18 /**
  19  * IndexPager is an efficient pager which uses a (roughly unique) index in the
  20  * data set to implement paging, rather than a "LIMIT offset,limit" clause.
  21  * In MySQL, such a limit/offset clause requires counting through the
  22  * specified number of offset rows to find the desired data, which can be
  23  * expensive for large offsets.
  24  *
  25  * ReverseChronologicalPager is a child class of the abstract IndexPager, and
  26  * contains  some formatting and display code which is specific to the use of
  27  * timestamps as  indexes. Here is a synopsis of its operation:
  28  *
  29  *    * The query is specified by the offset, limit and direction (dir)
  30  *      parameters, in addition to any subclass-specific parameters.
  31  *    * The offset is the non-inclusive start of the DB query. A row with an
  32  *      index value equal to the offset will never be shown.
  33  *    * The query may either be done backwards, where the rows are returned by
  34  *      the database in the opposite order to which they are displayed to the
  35  *      user, or forwards. This is specified by the "dir" parameter, dir=prev
  36  *      means backwards, anything else means forwards. The offset value
  37  *      specifies the start of the database result set, which may be either
  38  *      the start or end of the displayed data set. This allows "previous"
  39  *      links to be implemented without knowledge of the index value at the
  40  *      start of the previous page.
  41  *    * An additional row beyond the user-specified limit is always requested.
  42  *      This allows us to tell whether we should display a "next" link in the
  43  *      case of forwards mode, or a "previous" link in the case of backwards
  44  *      mode. Determining whether to display the other link (the one for the
  45  *      page before the start of the database result set) can be done
  46  *      heuristically by examining the offset.
  47  *
  48  *    * An empty offset indicates that the offset condition should be omitted
  49  *      from the query. This naturally produces either the first page or the
  50  *      last page depending on the dir parameter.
  51  *
  52  *  Subclassing the pager to implement concrete functionality should be fairly
  53  *  simple, please see the examples in HistoryPage.php and
  54  *  SpecialIpblocklist.php. You just need to override formatRow(),
  55  *  getQueryInfo() and getIndexField(). Don't forget to call the parent
  56  *  constructor if you override it.
  57  *
  58  * @ingroup Pager
  59  */
  60 abstract class IndexPager implements Pager {
  61         public $mRequest;
  62         public $mLimitsShown = array( 20, 50, 100, 250, 500 );
  63         public $mDefaultLimit = 50;
  64         public $mOffset, $mLimit;
  65         public $mQueryDone = false;
  66         public $mDb;
  67         public $mPastTheEndRow;
  68
  69         /**
  70          * The index to actually be used for ordering.  This is a single string
  71          * even if multiple orderings are supported.
  72          */
  73         protected $mIndexField;
  74         /** For pages that support multiple types of ordering, which one to use.
  75          */
  76         protected $mOrderType;
  77         /**
  78          * $mDefaultDirection gives the direction to use when sorting results:
  79          * false for ascending, true for descending.  If $mIsBackwards is set, we
  80          * start from the opposite end, but we still sort the page itself according
  81          * to $mDefaultDirection.  E.g., if $mDefaultDirection is false but we're
  82          * going backwards, we'll display the last page of results, but the last
  83          * result will be at the bottom, not the top.
  84          *
  85          * Like $mIndexField, $mDefaultDirection will be a single value even if the
  86          * class supports multiple default directions for different order types.
  87          */
  88         public $mDefaultDirection;
  89         public $mIsBackwards;
  90
  91         /** True if the current result set is the first one */
  92         public $mIsFirst;
  93
  94         /**
  95          * Result object for the query. Warning: seek before use.
  96          */
  97         public $mResult;
  98
  99         public function __construct() {
 100                 global $wgRequest, $wgUser;
 101                 $this->mRequest = $wgRequest;
 102
 103                 # NB: the offset is quoted, not validated. It is treated as an
 104                 # arbitrary string to support the widest variety of index types. Be
 105                 # careful outputting it into HTML!
 106                 $this->mOffset = $this->mRequest->getText( 'offset' );
 107
 108                 # Use consistent behavior for the limit options
 109                 $this->mDefaultLimit = intval( $wgUser->getOption( 'rclimit' ) );
 110                 list( $this->mLimit, /* $offset */ ) = $this->mRequest->getLimitOffset();
 111
 112                 $this->mIsBackwards = ( $this->mRequest->getVal( 'dir' ) == 'prev' );
 113                 $this->mDb = wfGetDB( DB_SLAVE );
 114
 115                 $index = $this->getIndexField();
 116                 $order = $this->mRequest->getVal( 'order' );
 117                 if( is_array( $index ) && isset( $index[$order] ) ) {
 118                         $this->mOrderType = $order;
 119                         $this->mIndexField = $index[$order];
 120                 } elseif( is_array( $index ) ) {
 121                         # First element is the default
 122                         reset( $index );
 123                         list( $this->mOrderType, $this->mIndexField ) = each( $index );
 124                 } else {
 125                         # $index is not an array
 126                         $this->mOrderType = null;
 127                         $this->mIndexField = $index;
 128                 }
 129
 130                 if( !isset( $this->mDefaultDirection ) ) {
 131                         $dir = $this->getDefaultDirections();
 132                         $this->mDefaultDirection = is_array( $dir )
 133                                 ? $dir[$this->mOrderType]
 134                                 : $dir;
 135                 }
 136         }
 137
 138         /**
 139          * Do the query, using information from the object context. This function
 140          * has been kept minimal to make it overridable if necessary, to allow for
 141          * result sets formed from multiple DB queries.
 142          */
 143         function doQuery() {
 144                 # Use the child class name for profiling
 145                 $fname = __METHOD__ . ' (' . get_class( $this ) . ')';
 146                 wfProfileIn( $fname );
 147
 148                 $descending = ( $this->mIsBackwards == $this->mDefaultDirection );
 149                 # Plus an extra row so that we can tell the "next" link should be shown
 150                 $queryLimit = $this->mLimit + 1;
 151
 152                 $this->mResult = $this->reallyDoQuery(
 153                         $this->mOffset,
 154                         $queryLimit,
 155                         $descending
 156                 );
 157                 $this->extractResultInfo( $this->mOffset, $queryLimit, $this->mResult );
 158                 $this->mQueryDone = true;
 159
 160                 $this->preprocessResults( $this->mResult );
 161                 $this->mResult->rewind(); // Paranoia
 162
 163                 wfProfileOut( $fname );
 164         }
 165
 166         /**
 167          * Return the result wrapper.
 168          */
 169         function getResult() {
 170                 return $this->mResult;
 171         }
 172
 173         /**
 174          * Set the offset from an other source than $wgRequest
 175          */
 176         function setOffset( $offset ) {
 177                 $this->mOffset = $offset;
 178         }
 179         /**
 180          * Set the limit from an other source than $wgRequest
 181          */
 182         function setLimit( $limit ) {
 183                 $this->mLimit = $limit;
 184         }
 185
 186         /**
 187          * Extract some useful data from the result object for use by
 188          * the navigation bar, put it into $this
 189          *
 190          * @param $offset String: index offset, inclusive
 191          * @param $limit Integer: exact query limit
 192          * @param $res ResultWrapper
 193          */
 194         function extractResultInfo( $offset, $limit, ResultWrapper $res ) {
 195                 $numRows = $res->numRows();
 196                 if ( $numRows ) {
 197                         # Remove any table prefix from index field
 198                         $indexColumn = end( explode( '.', $this->mIndexField ) );
 199
 200                         $row = $res->fetchRow();
 201                         $firstIndex = $row[$indexColumn];
 202
 203                         # Discard the extra result row if there is one
 204                         if ( $numRows > $this->mLimit && $numRows > 1 ) {
 205                                 $res->seek( $numRows - 1 );
 206                                 $this->mPastTheEndRow = $res->fetchObject();
 207                                 $indexField = $this->mIndexField;
 208                                 $this->mPastTheEndIndex = $this->mPastTheEndRow->$indexField;
 209                                 $res->seek( $numRows - 2 );
 210                                 $row = $res->fetchRow();
 211                                 $lastIndex = $row[$indexColumn];
 212                         } else {
 213                                 $this->mPastTheEndRow = null;
 214                                 # Setting indexes to an empty string means that they will be
 215                                 # omitted if they would otherwise appear in URLs. It just so
 216                                 # happens that this  is the right thing to do in the standard
 217                                 # UI, in all the relevant cases.
 218                                 $this->mPastTheEndIndex = '';
 219                                 $res->seek( $numRows - 1 );
 220                                 $row = $res->fetchRow();
 221                                 $lastIndex = $row[$indexColumn];
 222                         }
 223                 } else {
 224                         $firstIndex = '';
 225                         $lastIndex = '';
 226                         $this->mPastTheEndRow = null;
 227                         $this->mPastTheEndIndex = '';
 228                 }
 229
 230                 if ( $this->mIsBackwards ) {
 231                         $this->mIsFirst = ( $numRows < $limit );
 232                         $this->mIsLast = ( $offset == '' );
 233                         $this->mLastShown = $firstIndex;
 234                         $this->mFirstShown = $lastIndex;
 235                 } else {
 236                         $this->mIsFirst = ( $offset == '' );
 237                         $this->mIsLast = ( $numRows < $limit );
 238                         $this->mLastShown = $lastIndex;
 239                         $this->mFirstShown = $firstIndex;
 240                 }
 241         }
 242
 243         /**
 244          * Get some text to go in brackets in the "function name" part of the SQL comment
 245          *
 246          * @return String
 247          */
 248         function getSqlComment() {
 249                 return get_class( $this );
 250         }
 251
 252         /**
 253          * Do a query with specified parameters, rather than using the object
 254          * context
 255          *
 256          * @param $offset String: index offset, inclusive
 257          * @param $limit Integer: exact query limit
 258          * @param $descending Boolean: query direction, false for ascending, true for descending
 259          * @return ResultWrapper
 260          */
 261         function reallyDoQuery( $offset, $limit, $descending ) {
 262                 $fname = __METHOD__ . ' (' . $this->getSqlComment() . ')';
 263                 $info = $this->getQueryInfo();
 264                 $tables = $info['tables'];
 265                 $fields = $info['fields'];
 266                 $conds = isset( $info['conds'] ) ? $info['conds'] : array();
 267                 $options = isset( $info['options'] ) ? $info['options'] : array();
 268                 $join_conds = isset( $info['join_conds'] ) ? $info['join_conds'] : array();
 269                 if ( $descending ) {
 270                         $options['ORDER BY'] = $this->mIndexField;
 271                         $operator = '>';
 272                 } else {
 273                         $options['ORDER BY'] = $this->mIndexField . ' DESC';
 274                         $operator = '<';
 275                 }
 276                 if ( $offset != '' ) {
 277                         $conds[] = $this->mIndexField . $operator . $this->mDb->addQuotes( $offset );
 278                 }
 279                 $options['LIMIT'] = intval( $limit );
 280                 $res = $this->mDb->select( $tables, $fields, $conds, $fname, $options, $join_conds );
 281                 return new ResultWrapper( $this->mDb, $res );
 282         }
 283
 284         /**
 285          * Pre-process results; useful for performing batch existence checks, etc.
 286          *
 287          * @param $result ResultWrapper
 288          */
 289         protected function preprocessResults( $result ) {}
 290
 291         /**
 292          * Get the formatted result list. Calls getStartBody(), formatRow() and
 293          * getEndBody(), concatenates the results and returns them.
 294          *
 295          * @return String
 296          */
 297         function getBody() {
 298                 if ( !$this->mQueryDone ) {
 299                         $this->doQuery();
 300                 }
 301                 # Don't use any extra rows returned by the query
 302                 $numRows = min( $this->mResult->numRows(), $this->mLimit );
 303
 304                 $s = $this->getStartBody();
 305                 if ( $numRows ) {
 306                         if ( $this->mIsBackwards ) {
 307                                 for ( $i = $numRows - 1; $i >= 0; $i-- ) {
 308                                         $this->mResult->seek( $i );
 309                                         $row = $this->mResult->fetchObject();
 310                                         $s .= $this->formatRow( $row );
 311                                 }
 312                         } else {
 313                                 $this->mResult->seek( 0 );
 314                                 for ( $i = 0; $i < $numRows; $i++ ) {
 315                                         $row = $this->mResult->fetchObject();
 316                                         $s .= $this->formatRow( $row );
 317                                 }
 318                         }
 319                 } else {
 320                         $s .= $this->getEmptyBody();
 321                 }
 322                 $s .= $this->getEndBody();
 323                 return $s;
 324         }
 325
 326         /**
 327          * Make a self-link
 328          *
 329          * @param $text String: text displayed on the link
 330          * @param $query Array: associative array of paramter to be in the query string
 331          * @param $type String: value of the "rel" attribute
 332          * @return String: HTML fragment
 333          */
 334         function makeLink($text, $query = null, $type=null) {
 335                 if ( $query === null ) {
 336                         return $text;
 337                 }
 338
 339                 $attrs = array();
 340                 if( in_array( $type, array( 'first', 'prev', 'next', 'last' ) ) ) {
 341                         # HTML5 rel attributes
 342                         $attrs['rel'] = $type;
 343                 }
 344
 345                 if( $type ) {
 346                         $attrs['class'] = "mw-{$type}link";
 347                 }
 348                 return $this->getSkin()->link(
 349                         $this->getTitle(),
 350                         $text,
 351                         $attrs,
 352                         $query + $this->getDefaultQuery(),
 353                         array( 'noclasses', 'known' )
 354                 );
 355         }
 356
 357         /**
 358          * Hook into getBody(), allows text to be inserted at the start. This
 359          * will be called even if there are no rows in the result set.
 360          *
 361          * @return String
 362          */
 363         function getStartBody() {
 364                 return '';
 365         }
 366
 367         /**
 368          * Hook into getBody() for the end of the list
 369          *
 370          * @return String
 371          */
 372         function getEndBody() {
 373                 return '';
 374         }
 375
 376         /**
 377          * Hook into getBody(), for the bit between the start and the
 378          * end when there are no rows
 379          *
 380          * @return String
 381          */
 382         function getEmptyBody() {
 383                 return '';
 384         }
 385
 386         /**
 387          * Title used for self-links. Override this if you want to be able to
 388          * use a title other than $wgTitle
 389          *
 390          * @return Title object
 391          */
 392         function getTitle() {
 393                 return $GLOBALS['wgTitle'];
 394         }
 395
 396         /**
 397          * Get the current skin. This can be overridden if necessary.
 398          *
 399          * @return Skin object
 400          */
 401         function getSkin() {
 402                 if ( !isset( $this->mSkin ) ) {
 403                         global $wgUser;
 404                         $this->mSkin = $wgUser->getSkin();
 405                 }
 406                 return $this->mSkin;
 407         }
 408
 409         /**
 410          * Get an array of query parameters that should be put into self-links.
 411          * By default, all parameters passed in the URL are used, except for a
 412          * short blacklist.
 413          *
 414          * @return Associative array
 415          */
 416         function getDefaultQuery() {
 417                 if ( !isset( $this->mDefaultQuery ) ) {
 418                         $this->mDefaultQuery = $_GET;
 419                         unset( $this->mDefaultQuery['title'] );
 420                         unset( $this->mDefaultQuery['dir'] );
 421                         unset( $this->mDefaultQuery['offset'] );
 422                         unset( $this->mDefaultQuery['limit'] );
 423                         unset( $this->mDefaultQuery['order'] );
 424                         unset( $this->mDefaultQuery['month'] );
 425                         unset( $this->mDefaultQuery['year'] );
 426                 }
 427                 return $this->mDefaultQuery;
 428         }
 429
 430         /**
 431          * Get the number of rows in the result set
 432          *
 433          * @return Integer
 434          */
 435         function getNumRows() {
 436                 if ( !$this->mQueryDone ) {
 437                         $this->doQuery();
 438                 }
 439                 return $this->mResult->numRows();
 440         }
 441
 442         /**
 443          * Get a URL query array for the prev, next, first and last links.
 444          *
 445          * @return Array
 446          */
 447         function getPagingQueries() {
 448                 if ( !$this->mQueryDone ) {
 449                         $this->doQuery();
 450                 }
 451
 452                 # Don't announce the limit everywhere if it's the default
 453                 $urlLimit = $this->mLimit == $this->mDefaultLimit ? '' : $this->mLimit;
 454
 455                 if ( $this->mIsFirst ) {
 456                         $prev = false;
 457                         $first = false;
 458                 } else {
 459                         $prev = array(
 460                                 'dir' => 'prev',
 461                                 'offset' => $this->mFirstShown,
 462                                 'limit' => $urlLimit
 463                         );
 464                         $first = array( 'limit' => $urlLimit );
 465                 }
 466                 if ( $this->mIsLast ) {
 467                         $next = false;
 468                         $last = false;
 469                 } else {
 470                         $next = array( 'offset' => $this->mLastShown, 'limit' => $urlLimit );
 471                         $last = array( 'dir' => 'prev', 'limit' => $urlLimit );
 472                 }
 473                 return array(
 474                         'prev' => $prev,
 475                         'next' => $next,
 476                         'first' => $first,
 477                         'last' => $last
 478                 );
 479         }
 480
 481         /**
 482          * Returns whether to show the "navigation bar"
 483          *
 484          * @return Boolean
 485          */
 486         function isNavigationBarShown() {
 487                 if ( !$this->mQueryDone ) {
 488                         $this->doQuery();
 489                 }
 490                 // Hide navigation by default if there is nothing to page
 491                 return !($this->mIsFirst && $this->mIsLast);
 492         }
 493
 494         /**
 495          * Get paging links. If a link is disabled, the item from $disabledTexts
 496          * will be used. If there is no such item, the unlinked text from
 497          * $linkTexts will be used. Both $linkTexts and $disabledTexts are arrays
 498          * of HTML.
 499          *
 500          * @return Array
 501          */
 502         function getPagingLinks( $linkTexts, $disabledTexts = array() ) {
 503                 $queries = $this->getPagingQueries();
 504                 $links = array();
 505                 foreach ( $queries as $type => $query ) {
 506                         if ( $query !== false ) {
 507                                 $links[$type] = $this->makeLink(
 508                                         $linkTexts[$type],
 509                                         $queries[$type],
 510                                         $type
 511                                 );
 512                         } elseif ( isset( $disabledTexts[$type] ) ) {
 513                                 $links[$type] = $disabledTexts[$type];
 514                         } else {
 515                                 $links[$type] = $linkTexts[$type];
 516                         }
 517                 }
 518                 return $links;
 519         }
 520
 521         function getLimitLinks() {
 522                 global $wgLang;
 523                 $links = array();
 524                 if ( $this->mIsBackwards ) {
 525                         $offset = $this->mPastTheEndIndex;
 526                 } else {
 527                         $offset = $this->mOffset;
 528                 }
 529                 foreach ( $this->mLimitsShown as $limit ) {
 530                         $links[] = $this->makeLink(
 531                                 $wgLang->formatNum( $limit ),
 532                                 array( 'offset' => $offset, 'limit' => $limit ),
 533                                 'num'
 534                         );
 535                 }
 536                 return $links;
 537         }
 538
 539         /**
 540          * Abstract formatting function. This should return an HTML string
 541          * representing the result row $row. Rows will be concatenated and
 542          * returned by getBody()
 543          *
 544          * @param $row Object: database row
 545          * @return String
 546          */
 547         abstract function formatRow( $row );
 548
 549         /**
 550          * This function should be overridden to provide all parameters
 551          * needed for the main paged query. It returns an associative
 552          * array with the following elements:
 553          *    tables => Table(s) for passing to Database::select()
 554          *    fields => Field(s) for passing to Database::select(), may be *
 555          *    conds => WHERE conditions
 556          *    options => option array
 557          *    join_conds => JOIN conditions
 558          *
 559          * @return Array
 560          */
 561         abstract function getQueryInfo();
 562
 563         /**
 564          * This function should be overridden to return the name of the index fi-
 565          * eld.  If the pager supports multiple orders, it may return an array of
 566          * 'querykey' => 'indexfield' pairs, so that a request with &count=querykey
 567          * will use indexfield to sort.  In this case, the first returned key is
 568          * the default.
 569          *
 570          * Needless to say, it's really not a good idea to use a non-unique index
 571          * for this!  That won't page right.
 572          */
 573         abstract function getIndexField();
 574
 575         /**
 576          * Return the default sorting direction: false for ascending, true for de-
 577          * scending.  You can also have an associative array of ordertype => dir,
 578          * if multiple order types are supported.  In this case getIndexField()
 579          * must return an array, and the keys of that must exactly match the keys
 580          * of this.
 581          *
 582          * For backward compatibility, this method's return value will be ignored
 583          * if $this->mDefaultDirection is already set when the constructor is
 584          * called, for instance if it's statically initialized.  In that case the
 585          * value of that variable (which must be a boolean) will be used.
 586          *
 587          * Note that despite its name, this does not return the value of the
 588          * $this->mDefaultDirection member variable.  That's the default for this
 589          * particular instantiation, which is a single value.  This is the set of
 590          * all defaults for the class.
 591          *
 592          * @return Boolean
 593          */
 594         protected function getDefaultDirections() { return false; }
 595 }
 596
 597
 598 /**
 599  * IndexPager with an alphabetic list and a formatted navigation bar
 600  * @ingroup Pager
 601  */
 602 abstract class AlphabeticPager extends IndexPager {
 603         /**
 604          * Shamelessly stolen bits from ReverseChronologicalPager,
 605          * didn't want to do class magic as may be still revamped
 606          */
 607         function getNavigationBar() {
 608                 global $wgLang;
 609
 610                 if ( !$this->isNavigationBarShown() ) return '';
 611
 612                 if( isset( $this->mNavigationBar ) ) {
 613                         return $this->mNavigationBar;
 614                 }
 615
 616                 $opts = array( 'parsemag', 'escapenoentities' );
 617                 $linkTexts = array(
 618                         'prev' => wfMsgExt(
 619                                 'prevn',
 620                                 $opts,
 621                                 $wgLang->formatNum( $this->mLimit )
 622                         ),
 623                         'next' => wfMsgExt(
 624                                 'nextn',
 625                                 $opts,
 626                                 $wgLang->formatNum($this->mLimit )
 627                         ),
 628                         'first' => wfMsgExt( 'page_first', $opts ),
 629                         'last' => wfMsgExt( 'page_last', $opts )
 630                 );
 631
 632                 $pagingLinks = $this->getPagingLinks( $linkTexts );
 633                 $limitLinks = $this->getLimitLinks();
 634                 $limits = $wgLang->pipeList( $limitLinks );
 635
 636                 $this->mNavigationBar =
 637                         "(" . $wgLang->pipeList(
 638                                 array( $pagingLinks['first'],
 639                                 $pagingLinks['last'] )
 640                         ) . ") " .
 641                         wfMsgHtml( 'viewprevnext', $pagingLinks['prev'],
 642                         $pagingLinks['next'], $limits );
 643
 644                 if( !is_array( $this->getIndexField() ) ) {
 645                         # Early return to avoid undue nesting
 646                         return $this->mNavigationBar;
 647                 }
 648
 649                 $extra = '';
 650                 $first = true;
 651                 $msgs = $this->getOrderTypeMessages();
 652                 foreach( array_keys( $msgs ) as $order ) {
 653                         if( $first ) {
 654                                 $first = false;
 655                         } else {
 656                                 $extra .= wfMsgExt( 'pipe-separator' , 'escapenoentities' );
 657                         }
 658
 659                         if( $order == $this->mOrderType ) {
 660                                 $extra .= wfMsgHTML( $msgs[$order] );
 661                         } else {
 662                                 $extra .= $this->makeLink(
 663                                         wfMsgHTML( $msgs[$order] ),
 664                                         array( 'order' => $order )
 665                                 );
 666                         }
 667                 }
 668
 669                 if( $extra !== '' ) {
 670                         $this->mNavigationBar .= " ($extra)";
 671                 }
 672
 673                 return $this->mNavigationBar;
 674         }
 675
 676         /**
 677          * If this supports multiple order type messages, give the message key for
 678          * enabling each one in getNavigationBar.  The return type is an associa-
 679          * tive array whose keys must exactly match the keys of the array returned
 680          * by getIndexField(), and whose values are message keys.
 681          *
 682          * @return Array
 683          */
 684         protected function getOrderTypeMessages() {
 685                 return null;
 686         }
 687 }
 688
 689 /**
 690  * IndexPager with a formatted navigation bar
 691  * @ingroup Pager
 692  */
 693 abstract class ReverseChronologicalPager extends IndexPager {
 694         public $mDefaultDirection = true;
 695         public $mYear;
 696         public $mMonth;
 697
 698         function __construct() {
 699                 parent::__construct();
 700         }
 701
 702         function getNavigationBar() {
 703                 global $wgLang;
 704
 705                 if ( !$this->isNavigationBarShown() ) return '';
 706
 707                 if ( isset( $this->mNavigationBar ) ) {
 708                         return $this->mNavigationBar;
 709                 }
 710                 $nicenumber = $wgLang->formatNum( $this->mLimit );
 711                 $linkTexts = array(
 712                         'prev' => wfMsgExt(
 713                                 'pager-newer-n',
 714                                 array( 'parsemag', 'escape' ),
 715                                 $nicenumber
 716                         ),
 717                         'next' => wfMsgExt(
 718                                 'pager-older-n',
 719                                 array( 'parsemag', 'escape' ),
 720                                 $nicenumber
 721                         ),
 722                         'first' => wfMsgHtml( 'histlast' ),
 723                         'last' => wfMsgHtml( 'histfirst' )
 724                 );
 725
 726                 $pagingLinks = $this->getPagingLinks( $linkTexts );
 727                 $limitLinks = $this->getLimitLinks();
 728                 $limits = $wgLang->pipeList( $limitLinks );
 729
 730                 $this->mNavigationBar = "({$pagingLinks['first']}" .
 731                         wfMsgExt( 'pipe-separator' , 'escapenoentities' ) .
 732                         "{$pagingLinks['last']}) " .
 733                         wfMsgHTML(
 734                                 'viewprevnext',
 735                                 $pagingLinks['prev'], $pagingLinks['next'],
 736                                 $limits
 737                         );
 738                 return $this->mNavigationBar;
 739         }
 740
 741         function getDateCond( $year, $month ) {
 742                 $year = intval($year);
 743                 $month = intval($month);
 744                 // Basic validity checks
 745                 $this->mYear = $year > 0 ? $year : false;
 746                 $this->mMonth = ($month > 0 && $month < 13) ? $month : false;
 747                 // Given an optional year and month, we need to generate a timestamp
 748                 // to use as "WHERE rev_timestamp <= result"
 749                 // Examples: year = 2006 equals < 20070101 (+000000)
 750                 // year=2005, month=1    equals < 20050201
 751                 // year=2005, month=12   equals < 20060101
 752                 if ( !$this->mYear && !$this->mMonth ) {
 753                         return;
 754                 }
 755                 if ( $this->mYear ) {
 756                         $year = $this->mYear;
 757                 } else {
 758                         // If no year given, assume the current one
 759                         $year = gmdate( 'Y' );
 760                         // If this month hasn't happened yet this year, go back to last year's month
 761                         if( $this->mMonth > gmdate( 'n' ) ) {
 762                                 $year--;
 763                         }
 764                 }
 765                 if ( $this->mMonth ) {
 766                         $month = $this->mMonth + 1;
 767                         // For December, we want January 1 of the next year
 768                         if ($month > 12) {
 769                                 $month = 1;
 770                                 $year++;
 771                         }
 772                 } else {
 773                         // No month implies we want up to the end of the year in question
 774                         $month = 1;
 775                         $year++;
 776                 }
 777                 // Y2K38 bug
 778                 if ( $year > 2032 ) {
 779                         $year = 2032;
 780                 }
 781                 $ymd = (int)sprintf( "%04d%02d01", $year, $month );
 782                 if ( $ymd > 20320101 ) {
 783                         $ymd = 20320101;
 784                 }
 785                 $this->mOffset = $this->mDb->timestamp( "${ymd}000000" );
 786         }
 787 }
 788
 789 /**
 790  * Table-based display with a user-selectable sort order
 791  * @ingroup Pager
 792  */
 793 abstract class TablePager extends IndexPager {
 794         var $mSort;
 795         var $mCurrentRow;
 796
 797         function __construct() {
 798                 global $wgRequest;
 799                 $this->mSort = $wgRequest->getText( 'sort' );
 800                 if ( !array_key_exists( $this->mSort, $this->getFieldNames() ) ) {
 801                         $this->mSort = $this->getDefaultSort();
 802                 }
 803                 if ( $wgRequest->getBool( 'asc' ) ) {
 804                         $this->mDefaultDirection = false;
 805                 } elseif ( $wgRequest->getBool( 'desc' ) ) {
 806                         $this->mDefaultDirection = true;
 807                 } /* Else leave it at whatever the class default is */
 808
 809                 parent::__construct();
 810         }
 811
 812         function getStartBody() {
 813                 global $wgStylePath;
 814                 $tableClass = htmlspecialchars( $this->getTableClass() );
 815                 $sortClass = htmlspecialchars( $this->getSortHeaderClass() );
 816
 817                 $s = "<table border='1' class=\"$tableClass\"><thead><tr>\n";
 818                 $fields = $this->getFieldNames();
 819
 820                 # Make table header
 821                 foreach ( $fields as $field => $name ) {
 822                         if ( strval( $name ) == '' ) {
 823                                 $s .= "<th>&#160;</th>\n";
 824                         } elseif ( $this->isFieldSortable( $field ) ) {
 825                                 $query = array( 'sort' => $field, 'limit' => $this->mLimit );
 826                                 if ( $field == $this->mSort ) {
 827                                         # This is the sorted column
 828                                         # Prepare a link that goes in the other sort order
 829                                         if ( $this->mDefaultDirection ) {
 830                                                 # Descending
 831                                                 $image = 'Arr_u.png';
 832                                                 $query['asc'] = '1';
 833                                                 $query['desc'] = '';
 834                                                 $alt = htmlspecialchars( wfMsg( 'descending_abbrev' ) );
 835                                         } else {
 836                                                 # Ascending
 837                                                 $image = 'Arr_d.png';
 838                                                 $query['asc'] = '';
 839                                                 $query['desc'] = '1';
 840                                                 $alt = htmlspecialchars( wfMsg( 'ascending_abbrev' ) );
 841                                         }
 842                                         $image = htmlspecialchars( "$wgStylePath/common/images/$image" );
 843                                         $link = $this->makeLink(
 844                                                 "<img width=\"12\" height=\"12\" alt=\"$alt\" src=\"$image\" />" .
 845                                                 htmlspecialchars( $name ), $query );
 846                                         $s .= "<th class=\"$sortClass\">$link</th>\n";
 847                                 } else {
 848                                         $s .= '<th>' . $this->makeLink( htmlspecialchars( $name ), $query ) . "</th>\n";
 849                                 }
 850                         } else {
 851                                 $s .= '<th>' . htmlspecialchars( $name ) . "</th>\n";
 852                         }
 853                 }
 854                 $s .= "</tr></thead><tbody>\n";
 855                 return $s;
 856         }
 857
 858         function getEndBody() {
 859                 return "</tbody></table>\n";
 860         }
 861
 862         function getEmptyBody() {
 863                 $colspan = count( $this->getFieldNames() );
 864                 $msgEmpty = wfMsgHtml( 'table_pager_empty' );
 865                 return "<tr><td colspan=\"$colspan\">$msgEmpty</td></tr>\n";
 866         }
 867
 868         function formatRow( $row ) {
 869                 $this->mCurrentRow = $row;      # In case formatValue etc need to know
 870                 $s = Xml::openElement( 'tr', $this->getRowAttrs($row) );
 871                 $fieldNames = $this->getFieldNames();
 872                 foreach ( $fieldNames as $field => $name ) {
 873                         $value = isset( $row->$field ) ? $row->$field : null;
 874                         $formatted = strval( $this->formatValue( $field, $value ) );
 875                         if ( $formatted == '' ) {
 876                                 $formatted = '&#160;';
 877                         }
 878                         $s .= Xml::tags( 'td', $this->getCellAttrs( $field, $value ), $formatted );
 879                 }
 880                 $s .= "</tr>\n";
 881                 return $s;
 882         }
 883
 884         /**
 885          * Get a class name to be applied to the given row.
 886          *
 887          * @param $row Object: the database result row
 888          * @return String
 889          */
 890         function getRowClass( $row ) {
 891                 return '';
 892         }
 893
 894         /**
 895          * Get attributes to be applied to the given row.
 896          *
 897          * @param $row Object: the database result row
 898          * @return Associative array
 899          */
 900         function getRowAttrs( $row ) {
 901                 return array( 'class' => $this->getRowClass( $row ) );
 902         }
 903
 904         /**
 905          * Get any extra attributes to be applied to the given cell. Don't
 906          * take this as an excuse to hardcode styles; use classes and
 907          * CSS instead.  Row context is available in $this->mCurrentRow
 908          *
 909          * @param $field The column
 910          * @param $value The cell contents
 911          * @return Associative array
 912          */
 913         function getCellAttrs( $field, $value ) {
 914                 return array( 'class' => 'TablePager_col_' . $field );
 915         }
 916
 917         function getIndexField() {
 918                 return $this->mSort;
 919         }
 920
 921         function getTableClass() {
 922                 return 'TablePager';
 923         }
 924
 925         function getNavClass() {
 926                 return 'TablePager_nav';
 927         }
 928
 929         function getSortHeaderClass() {
 930                 return 'TablePager_sort';
 931         }
 932
 933         /**
 934          * A navigation bar with images
 935          */
 936         function getNavigationBar() {
 937                 global $wgStylePath, $wgContLang;
 938
 939                 if ( !$this->isNavigationBarShown() ) return '';
 940
 941                 $path = "$wgStylePath/common/images";
 942                 $labels = array(
 943                         'first' => 'table_pager_first',
 944                         'prev' => 'table_pager_prev',
 945                         'next' => 'table_pager_next',
 946                         'last' => 'table_pager_last',
 947                 );
 948                 $images = array(
 949                         'first' => 'arrow_first_25.png',
 950                         'prev' => 'arrow_left_25.png',
 951                         'next' => 'arrow_right_25.png',
 952                         'last' => 'arrow_last_25.png',
 953                 );
 954                 $disabledImages = array(
 955                         'first' => 'arrow_disabled_first_25.png',
 956                         'prev' => 'arrow_disabled_left_25.png',
 957                         'next' => 'arrow_disabled_right_25.png',
 958                         'last' => 'arrow_disabled_last_25.png',
 959                 );
 960                 if( $wgContLang->isRTL() ) {
 961                         $keys = array_keys( $labels );
 962                         $images = array_combine( $keys, array_reverse( $images ) );
 963                         $disabledImages = array_combine( $keys, array_reverse( $disabledImages ) );
 964                 }
 965
 966                 $linkTexts = array();
 967                 $disabledTexts = array();
 968                 foreach ( $labels as $type => $label ) {
 969                         $msgLabel = wfMsgHtml( $label );
 970                         $linkTexts[$type] = "<img src=\"$path/{$images[$type]}\" alt=\"$msgLabel\"/><br />$msgLabel";
 971                         $disabledTexts[$type] = "<img src=\"$path/{$disabledImages[$type]}\" alt=\"$msgLabel\"/><br />$msgLabel";
 972                 }
 973                 $links = $this->getPagingLinks( $linkTexts, $disabledTexts );
 974
 975                 $navClass = htmlspecialchars( $this->getNavClass() );
 976                 $s = "<table class=\"$navClass\" align=\"center\" cellpadding=\"3\"><tr>\n";
 977                 $cellAttrs = 'valign="top" align="center" width="' . 100 / count( $links ) . '%"';
 978                 foreach ( $labels as $type => $label ) {
 979                         $s .= "<td $cellAttrs>{$links[$type]}</td>\n";
 980                 }
 981                 $s .= "</tr></table>\n";
 982                 return $s;
 983         }
 984
 985         /**
 986          * Get a <select> element which has options for each of the allowed limits
 987          *
 988          * @return String: HTML fragment
 989          */
 990         function getLimitSelect() {
 991                 global $wgLang;
 992
 993                 # Add the current limit from the query string
 994                 # to avoid that the limit is lost after clicking Go next time
 995                 if ( !in_array( $this->mLimit, $this->mLimitsShown ) ) {
 996                         $this->mLimitsShown[] = $this->mLimit;
 997                         sort( $this->mLimitsShown );
 998                 }
 999                 $s = Html::openElement( 'select', array( 'name' => 'limit' ) ) . "\n";
1000                 foreach ( $this->mLimitsShown as $key => $value ) {
1001                         # The pair is either $index => $limit, in which case the $value
1002                         # will be numeric, or $limit => $text, in which case the $value
1003                         # will be a string.
1004                         if( is_int( $value ) ){
1005                                 $limit = $value;
1006                                 $text = $wgLang->formatNum( $limit );
1007                         } else {
1008                                 $limit = $key;
1009                                 $text = $value;
1010                         }
1011                         $s .= Xml::option( $text, $limit, $limit == $this->mLimit ) . "\n";
1012                 }
1013                 $s .= Html::closeElement( 'select' );
1014                 return $s;
1015         }
1016
1017         /**
1018          * Get <input type="hidden"> elements for use in a method="get" form.
1019          * Resubmits all defined elements of the $_GET array, except for a
1020          * blacklist, passed in the $blacklist parameter.
1021          *
1022          * @return String: HTML fragment
1023          */
1024         function getHiddenFields( $blacklist = array() ) {
1025                 $blacklist = (array)$blacklist;
1026                 $query = $_GET;
1027                 foreach ( $blacklist as $name ) {
1028                         unset( $query[$name] );
1029                 }
1030                 $s = '';
1031                 foreach ( $query as $name => $value ) {
1032                         $encName = htmlspecialchars( $name );
1033                         $encValue = htmlspecialchars( $value );
1034                         $s .= "<input type=\"hidden\" name=\"$encName\" value=\"$encValue\"/>\n";
1035                 }
1036                 return $s;
1037         }
1038
1039         /**
1040          * Get a form containing a limit selection dropdown
1041          *
1042          * @return String: HTML fragment
1043          */
1044         function getLimitForm() {
1045                 global $wgScript;
1046
1047                 # Make the select with some explanatory text
1048                 $msgSubmit = wfMsgHtml( 'table_pager_limit_submit' );
1049                 return
1050                         Xml::openElement(
1051                                 'form',
1052                                 array(
1053                                         'method' => 'get',
1054                                         'action' => $wgScript
1055                                 )
1056                         ) . "\n" .
1057                         wfMsgHtml( 'table_pager_limit', $this->getLimitSelect() ) .
1058                         "\n<input type=\"submit\" value=\"$msgSubmit\"/>\n" .
1059                         $this->getHiddenFields( array( 'limit' ) ) .
1060                         "</form>\n";
1061         }
1062
1063         /**
1064          * Return true if the named field should be sortable by the UI, false
1065          * otherwise
1066          *
1067          * @param $field String
1068          */
1069         abstract function isFieldSortable( $field );
1070
1071         /**
1072          * Format a table cell. The return value should be HTML, but use an empty
1073          * string not &#160; for empty cells. Do not include the <td> and </td>.
1074          *
1075          * The current result row is available as $this->mCurrentRow, in case you
1076          * need more context.
1077          *
1078          * @param $name String: the database field name
1079          * @param $value String: the value retrieved from the database
1080          */
1081         abstract function formatValue( $name, $value );
1082
1083         /**
1084          * The database field name used as a default sort order
1085          */
1086         abstract function getDefaultSort();
1087
1088         /**
1089          * An array mapping database field names to a textual description of the
1090          * field name, for use in the table header. The description should be plain
1091          * text, it will be HTML-escaped later.
1092          */
1093         abstract function getFieldNames();
1094 }