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 PageHistory.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 e-
  71          * ven if multiple orderings are supported.
  72          */
  73         protected $mIndexField;
  74         /** For pages that support multiple types of ordering, which one to use. */
  75         protected $mOrderType;
  76         /**
  77          * $mDefaultDirection gives the direction to use when sorting results:
  78          * false for ascending, true for descending.  If $mIsBackwards is set, we
  79          * start from the opposite end, but we still sort the page itself according
  80          * to $mDefaultDirection.  E.g., if $mDefaultDirection is false but we're
  81          * going backwards, we'll display the last page of results, but the last
  82          * result will be at the bottom, not the top.
  83          *
  84          * Like $mIndexField, $mDefaultDirection will be a single value even if the
  85          * class supports multiple default directions for different order types.
  86          */
  87         public $mDefaultDirection;
  88         public $mIsBackwards;
  89
  90         /**
  91          * Result object for the query. Warning: seek before use.
  92          */
  93         public $mResult;
  94
  95         public function __construct() {
  96                 global $wgRequest, $wgUser;
  97                 $this->mRequest = $wgRequest;
  98
  99                 # NB: the offset is quoted, not validated. It is treated as an
 100                 # arbitrary string to support the widest variety of index types. Be
 101                 # careful outputting it into HTML!
 102                 $this->mOffset = $this->mRequest->getText( 'offset' );
 103
 104                 # Use consistent behavior for the limit options
 105                 $this->mDefaultLimit = intval( $wgUser->getOption( 'rclimit' ) );
 106                 list( $this->mLimit, /* $offset */ ) = $this->mRequest->getLimitOffset();
 107
 108                 $this->mIsBackwards = ( $this->mRequest->getVal( 'dir' ) == 'prev' );
 109                 $this->mDb = wfGetDB( DB_SLAVE );
 110
 111                 $index = $this->getIndexField();
 112                 $order = $this->mRequest->getVal( 'order' );
 113                 if( is_array( $index ) && isset( $index[$order] ) ) {
 114                         $this->mOrderType = $order;
 115                         $this->mIndexField = $index[$order];
 116                 } elseif( is_array( $index ) ) {
 117                         # First element is the default
 118                         reset( $index );
 119                         list( $this->mOrderType, $this->mIndexField ) = each( $index );
 120                 } else {
 121                         # $index is not an array
 122                         $this->mOrderType = null;
 123                         $this->mIndexField = $index;
 124                 }
 125
 126                 if( !isset( $this->mDefaultDirection ) ) {
 127                         $dir = $this->getDefaultDirections();
 128                         $this->mDefaultDirection = is_array( $dir )
 129                                 ? $dir[$this->mOrderType]
 130                                 : $dir;
 131                 }
 132         }
 133
 134         /**
 135          * Do the query, using information from the object context. This function
 136          * has been kept minimal to make it overridable if necessary, to allow for
 137          * result sets formed from multiple DB queries.
 138          */
 139         function doQuery() {
 140                 # Use the child class name for profiling
 141                 $fname = __METHOD__ . ' (' . get_class( $this ) . ')';
 142                 wfProfileIn( $fname );
 143
 144                 $descending = ( $this->mIsBackwards == $this->mDefaultDirection );
 145                 # Plus an extra row so that we can tell the "next" link should be shown
 146                 $queryLimit = $this->mLimit + 1;
 147
 148                 $this->mResult = $this->reallyDoQuery( $this->mOffset, $queryLimit, $descending );
 149                 $this->extractResultInfo( $this->mOffset, $queryLimit, $this->mResult );
 150                 $this->mQueryDone = true;
 151
 152                 $this->preprocessResults( $this->mResult );
 153                 $this->mResult->rewind(); // Paranoia
 154
 155                 wfProfileOut( $fname );
 156         }
 157
 158         /**
 159          * Return the result wrapper.
 160          */
 161         function getResult() {
 162                 return $this->mResult;
 163         }
 164
 165         /**
 166          * Extract some useful data from the result object for use by
 167          * the navigation bar, put it into $this
 168          */
 169         function extractResultInfo( $offset, $limit, ResultWrapper $res ) {
 170                 $numRows = $res->numRows();
 171                 if ( $numRows ) {
 172                         $row = $res->fetchRow();
 173                         $firstIndex = $row[$this->mIndexField];
 174
 175                         # Discard the extra result row if there is one
 176                         if ( $numRows > $this->mLimit && $numRows > 1 ) {
 177                                 $res->seek( $numRows - 1 );
 178                                 $this->mPastTheEndRow = $res->fetchObject();
 179                                 $indexField = $this->mIndexField;
 180                                 $this->mPastTheEndIndex = $this->mPastTheEndRow->$indexField;
 181                                 $res->seek( $numRows - 2 );
 182                                 $row = $res->fetchRow();
 183                                 $lastIndex = $row[$this->mIndexField];
 184                         } else {
 185                                 $this->mPastTheEndRow = null;
 186                                 # Setting indexes to an empty string means that they will be
 187                                 # omitted if they would otherwise appear in URLs. It just so
 188                                 # happens that this  is the right thing to do in the standard
 189                                 # UI, in all the relevant cases.
 190                                 $this->mPastTheEndIndex = '';
 191                                 $res->seek( $numRows - 1 );
 192                                 $row = $res->fetchRow();
 193                                 $lastIndex = $row[$this->mIndexField];
 194                         }
 195                 } else {
 196                         $firstIndex = '';
 197                         $lastIndex = '';
 198                         $this->mPastTheEndRow = null;
 199                         $this->mPastTheEndIndex = '';
 200                 }
 201
 202                 if ( $this->mIsBackwards ) {
 203                         $this->mIsFirst = ( $numRows < $limit );
 204                         $this->mIsLast = ( $offset == '' );
 205                         $this->mLastShown = $firstIndex;
 206                         $this->mFirstShown = $lastIndex;
 207                 } else {
 208                         $this->mIsFirst = ( $offset == '' );
 209                         $this->mIsLast = ( $numRows < $limit );
 210                         $this->mLastShown = $lastIndex;
 211                         $this->mFirstShown = $firstIndex;
 212                 }
 213         }
 214
 215         /**
 216          * Do a query with specified parameters, rather than using the object
 217          * context
 218          *
 219          * @param string $offset Index offset, inclusive
 220          * @param integer $limit Exact query limit
 221          * @param boolean $descending Query direction, false for ascending, true for descending
 222          * @return ResultWrapper
 223          */
 224         function reallyDoQuery( $offset, $limit, $descending ) {
 225                 $fname = __METHOD__ . ' (' . get_class( $this ) . ')';
 226                 $info = $this->getQueryInfo();
 227                 $tables = $info['tables'];
 228                 $fields = $info['fields'];
 229                 $conds = isset( $info['conds'] ) ? $info['conds'] : array();
 230                 $options = isset( $info['options'] ) ? $info['options'] : array();
 231                 $join_conds = isset( $info['join_conds'] ) ? $info['join_conds'] : array();
 232                 if ( $descending ) {
 233                         $options['ORDER BY'] = $this->mIndexField;
 234                         $operator = '>';
 235                 } else {
 236                         $options['ORDER BY'] = $this->mIndexField . ' DESC';
 237                         $operator = '<';
 238                 }
 239                 if ( $offset != '' ) {
 240                         $conds[] = $this->mIndexField . $operator . $this->mDb->addQuotes( $offset );
 241                 }
 242                 $options['LIMIT'] = intval( $limit );
 243                 $res = $this->mDb->select( $tables, $fields, $conds, $fname, $options, $join_conds );
 244                 return new ResultWrapper( $this->mDb, $res );
 245         }
 246
 247         /**
 248          * Pre-process results; useful for performing batch existence checks, etc.
 249          *
 250          * @param ResultWrapper $result Result wrapper
 251          */
 252         protected function preprocessResults( $result ) {}
 253
 254         /**
 255          * Get the formatted result list. Calls getStartBody(), formatRow() and
 256          * getEndBody(), concatenates the results and returns them.
 257          */
 258         function getBody() {
 259                 if ( !$this->mQueryDone ) {
 260                         $this->doQuery();
 261                 }
 262                 # Don't use any extra rows returned by the query
 263                 $numRows = min( $this->mResult->numRows(), $this->mLimit );
 264
 265                 $s = $this->getStartBody();
 266                 if ( $numRows ) {
 267                         if ( $this->mIsBackwards ) {
 268                                 for ( $i = $numRows - 1; $i >= 0; $i-- ) {
 269                                         $this->mResult->seek( $i );
 270                                         $row = $this->mResult->fetchObject();
 271                                         $s .= $this->formatRow( $row );
 272                                 }
 273                         } else {
 274                                 $this->mResult->seek( 0 );
 275                                 for ( $i = 0; $i < $numRows; $i++ ) {
 276                                         $row = $this->mResult->fetchObject();
 277                                         $s .= $this->formatRow( $row );
 278                                 }
 279                         }
 280                 } else {
 281                         $s .= $this->getEmptyBody();
 282                 }
 283                 $s .= $this->getEndBody();
 284                 return $s;
 285         }
 286
 287         /**
 288          * Make a self-link
 289          */
 290         function makeLink($text, $query = null, $type=null) {
 291                 if ( $query === null ) {
 292                         return $text;
 293                 }
 294                 if( $type == 'prev' || $type == 'next' ) {
 295                         $attrs = "rel=\"$type\"";
 296                 } elseif( $type == 'first' ) {
 297                         $attrs = "rel=\"start\"";
 298                 } else {
 299                         # HTML 4 has no rel="end" . . .
 300                         $attrs = '';
 301                 }
 302
 303                 if( $type ) {
 304                         $attrs .= " class=\"mw-{$type}link\"" ;
 305                 }
 306                 return $this->getSkin()->makeKnownLinkObj( $this->getTitle(), $text,
 307                         wfArrayToCGI( $query, $this->getDefaultQuery() ), '', '', $attrs );
 308         }
 309
 310         /**
 311          * Hook into getBody(), allows text to be inserted at the start. This
 312          * will be called even if there are no rows in the result set.
 313          */
 314         function getStartBody() {
 315                 return '';
 316         }
 317
 318         /**
 319          * Hook into getBody() for the end of the list
 320          */
 321         function getEndBody() {
 322                 return '';
 323         }
 324
 325         /**
 326          * Hook into getBody(), for the bit between the start and the
 327          * end when there are no rows
 328          */
 329         function getEmptyBody() {
 330                 return '';
 331         }
 332
 333         /**
 334          * Title used for self-links. Override this if you want to be able to
 335          * use a title other than $wgTitle
 336          */
 337         function getTitle() {
 338                 return $GLOBALS['wgTitle'];
 339         }
 340
 341         /**
 342          * Get the current skin. This can be overridden if necessary.
 343          */
 344         function getSkin() {
 345                 if ( !isset( $this->mSkin ) ) {
 346                         global $wgUser;
 347                         $this->mSkin = $wgUser->getSkin();
 348                 }
 349                 return $this->mSkin;
 350         }
 351
 352         /**
 353          * Get an array of query parameters that should be put into self-links.
 354          * By default, all parameters passed in the URL are used, except for a
 355          * short blacklist.
 356          */
 357         function getDefaultQuery() {
 358                 if ( !isset( $this->mDefaultQuery ) ) {
 359                         $this->mDefaultQuery = $_GET;
 360                         unset( $this->mDefaultQuery['title'] );
 361                         unset( $this->mDefaultQuery['dir'] );
 362                         unset( $this->mDefaultQuery['offset'] );
 363                         unset( $this->mDefaultQuery['limit'] );
 364                         unset( $this->mDefaultQuery['order'] );
 365                         unset( $this->mDefaultQuery['month'] );
 366                         unset( $this->mDefaultQuery['year'] );
 367                 }
 368                 return $this->mDefaultQuery;
 369         }
 370
 371         /**
 372          * Get the number of rows in the result set
 373          */
 374         function getNumRows() {
 375                 if ( !$this->mQueryDone ) {
 376                         $this->doQuery();
 377                 }
 378                 return $this->mResult->numRows();
 379         }
 380
 381         /**
 382          * Get a URL query array for the prev, next, first and last links.
 383          */
 384         function getPagingQueries() {
 385                 if ( !$this->mQueryDone ) {
 386                         $this->doQuery();
 387                 }
 388
 389                 # Don't announce the limit everywhere if it's the default
 390                 $urlLimit = $this->mLimit == $this->mDefaultLimit ? '' : $this->mLimit;
 391
 392                 if ( $this->mIsFirst ) {
 393                         $prev = false;
 394                         $first = false;
 395                 } else {
 396                         $prev = array( 'dir' => 'prev', 'offset' => $this->mFirstShown, 'limit' => $urlLimit );
 397                         $first = array( 'limit' => $urlLimit );
 398                 }
 399                 if ( $this->mIsLast ) {
 400                         $next = false;
 401                         $last = false;
 402                 } else {
 403                         $next = array( 'offset' => $this->mLastShown, 'limit' => $urlLimit );
 404                         $last = array( 'dir' => 'prev', 'limit' => $urlLimit );
 405                 }
 406                 return array( 'prev' => $prev, 'next' => $next, 'first' => $first, 'last' => $last );
 407         }
 408
 409         /**
 410          * Get paging links. If a link is disabled, the item from $disabledTexts
 411          * will be used. If there is no such item, the unlinked text from
 412          * $linkTexts will be used. Both $linkTexts and $disabledTexts are arrays
 413          * of HTML.
 414          */
 415         function getPagingLinks( $linkTexts, $disabledTexts = array() ) {
 416                 $queries = $this->getPagingQueries();
 417                 $links = array();
 418                 foreach ( $queries as $type => $query ) {
 419                         if ( $query !== false ) {
 420                                 $links[$type] = $this->makeLink( $linkTexts[$type], $queries[$type], $type );
 421                         } elseif ( isset( $disabledTexts[$type] ) ) {
 422                                 $links[$type] = $disabledTexts[$type];
 423                         } else {
 424                                 $links[$type] = $linkTexts[$type];
 425                         }
 426                 }
 427                 return $links;
 428         }
 429
 430         function getLimitLinks() {
 431                 global $wgLang;
 432                 $links = array();
 433                 if ( $this->mIsBackwards ) {
 434                         $offset = $this->mPastTheEndIndex;
 435                 } else {
 436                         $offset = $this->mOffset;
 437                 }
 438                 foreach ( $this->mLimitsShown as $limit ) {
 439                         $links[] = $this->makeLink( $wgLang->formatNum( $limit ),
 440                                 array( 'offset' => $offset, 'limit' => $limit ), 'num' );
 441                 }
 442                 return $links;
 443         }
 444
 445         /**
 446          * Abstract formatting function. This should return an HTML string
 447          * representing the result row $row. Rows will be concatenated and
 448          * returned by getBody()
 449          */
 450         abstract function formatRow( $row );
 451
 452         /**
 453          * This function should be overridden to provide all parameters
 454          * needed for the main paged query. It returns an associative
 455          * array with the following elements:
 456          *    tables => Table(s) for passing to Database::select()
 457          *    fields => Field(s) for passing to Database::select(), may be *
 458          *    conds => WHERE conditions
 459          *    options => option array
 460          */
 461         abstract function getQueryInfo();
 462
 463         /**
 464          * This function should be overridden to return the name of the index fi-
 465          * eld.  If the pager supports multiple orders, it may return an array of
 466          * 'querykey' => 'indexfield' pairs, so that a request with &count=querykey
 467          * will use indexfield to sort.  In this case, the first returned key is
 468          * the default.
 469          *
 470          * Needless to say, it's really not a good idea to use a non-unique index
 471          * for this!  That won't page right.
 472          */
 473         abstract function getIndexField();
 474
 475         /**
 476          * Return the default sorting direction: false for ascending, true for de-
 477          * scending.  You can also have an associative array of ordertype => dir,
 478          * if multiple order types are supported.  In this case getIndexField()
 479          * must return an array, and the keys of that must exactly match the keys
 480          * of this.
 481          *
 482          * For backward compatibility, this method's return value will be ignored
 483          * if $this->mDefaultDirection is already set when the constructor is
 484          * called, for instance if it's statically initialized.  In that case the
 485          * value of that variable (which must be a boolean) will be used.
 486          *
 487          * Note that despite its name, this does not return the value of the
 488          * $this->mDefaultDirection member variable.  That's the default for this
 489          * particular instantiation, which is a single value.  This is the set of
 490          * all defaults for the class.
 491          */
 492         protected function getDefaultDirections() { return false; }
 493 }
 494
 495
 496 /**
 497  * IndexPager with an alphabetic list and a formatted navigation bar
 498  * @ingroup Pager
 499  */
 500 abstract class AlphabeticPager extends IndexPager {
 501         /**
 502          * Shamelessly stolen bits from ReverseChronologicalPager,
 503          * didn't want to do class magic as may be still revamped
 504          */
 505         function getNavigationBar() {
 506                 global $wgLang;
 507
 508                 if( isset( $this->mNavigationBar ) ) {
 509                         return $this->mNavigationBar;
 510                 }
 511
 512                 $opts = array( 'parsemag', 'escapenoentities' );
 513                 $linkTexts = array(
 514                         'prev' => wfMsgExt( 'prevn', $opts, $wgLang->formatNum( $this->mLimit ) ),
 515                         'next' => wfMsgExt( 'nextn', $opts, $wgLang->formatNum($this->mLimit ) ),
 516                         'first' => wfMsgExt( 'page_first', $opts ),
 517                         'last' => wfMsgExt( 'page_last', $opts )
 518                 );
 519
 520                 $pagingLinks = $this->getPagingLinks( $linkTexts );
 521                 $limitLinks = $this->getLimitLinks();
 522                 $limits = implode( ' | ', $limitLinks );
 523
 524                 $this->mNavigationBar =
 525                         "({$pagingLinks['first']} | {$pagingLinks['last']}) " .
 526                         wfMsgHtml( 'viewprevnext', $pagingLinks['prev'],
 527                         $pagingLinks['next'], $limits );
 528
 529                 if( !is_array( $this->getIndexField() ) ) {
 530                         # Early return to avoid undue nesting
 531                         return $this->mNavigationBar;
 532                 }
 533
 534                 $extra = '';
 535                 $first = true;
 536                 $msgs = $this->getOrderTypeMessages();
 537                 foreach( array_keys( $msgs ) as $order ) {
 538                         if( $first ) {
 539                                 $first = false;
 540                         } else {
 541                                 $extra .= ' | ';
 542                         }
 543
 544                         if( $order == $this->mOrderType ) {
 545                                 $extra .= wfMsgHTML( $msgs[$order] );
 546                         } else {
 547                                 $extra .= $this->makeLink(
 548                                         wfMsgHTML( $msgs[$order] ),
 549                                         array( 'order' => $order )
 550                                 );
 551                         }
 552                 }
 553
 554                 if( $extra !== '' ) {
 555                         $this->mNavigationBar .= " ($extra)";
 556                 }
 557
 558                 return $this->mNavigationBar;
 559         }
 560
 561         /**
 562          * If this supports multiple order type messages, give the message key for
 563          * enabling each one in getNavigationBar.  The return type is an associa-
 564          * tive array whose keys must exactly match the keys of the array returned
 565          * by getIndexField(), and whose values are message keys.
 566          * @return array
 567          */
 568         protected function getOrderTypeMessages() {
 569                 return null;
 570         }
 571 }
 572
 573 /**
 574  * IndexPager with a formatted navigation bar
 575  * @ingroup Pager
 576  */
 577 abstract class ReverseChronologicalPager extends IndexPager {
 578         public $mDefaultDirection = true;
 579         public $mYear;
 580         public $mMonth;
 581
 582         function __construct() {
 583                 parent::__construct();
 584         }
 585
 586         function getNavigationBar() {
 587                 global $wgLang;
 588
 589                 if ( isset( $this->mNavigationBar ) ) {
 590                         return $this->mNavigationBar;
 591                 }
 592                 $nicenumber = $wgLang->formatNum( $this->mLimit );
 593                 $linkTexts = array(
 594                         'prev' => wfMsgExt( 'pager-newer-n', array( 'parsemag' ), $nicenumber ),
 595                         'next' => wfMsgExt( 'pager-older-n', array( 'parsemag' ), $nicenumber ),
 596                         'first' => wfMsgHtml( 'histlast' ),
 597                         'last' => wfMsgHtml( 'histfirst' )
 598                 );
 599
 600                 $pagingLinks = $this->getPagingLinks( $linkTexts );
 601                 $limitLinks = $this->getLimitLinks();
 602                 $limits = implode( ' | ', $limitLinks );
 603
 604                 $this->mNavigationBar = "({$pagingLinks['first']} | {$pagingLinks['last']}) " .
 605                         wfMsgHtml("viewprevnext", $pagingLinks['prev'], $pagingLinks['next'], $limits);
 606                 return $this->mNavigationBar;
 607         }
 608
 609         function getDateCond( $year, $month ) {
 610                 $year = intval($year);
 611                 $month = intval($month);
 612                 // Basic validity checks
 613                 $this->mYear = $year > 0 ? $year : false;
 614                 $this->mMonth = ($month > 0 && $month < 13) ? $month : false;
 615                 // Given an optional year and month, we need to generate a timestamp
 616                 // to use as "WHERE rev_timestamp <= result"
 617                 // Examples: year = 2006 equals < 20070101 (+000000)
 618                 // year=2005, month=1    equals < 20050201
 619                 // year=2005, month=12   equals < 20060101
 620                 if ( !$this->mYear && !$this->mMonth ) {
 621                         return;
 622                 }
 623                 if ( $this->mYear ) {
 624                         $year = $this->mYear;
 625                 } else {
 626                         // If no year given, assume the current one
 627                         $year = gmdate( 'Y' );
 628                         // If this month hasn't happened yet this year, go back to last year's month
 629                         if( $this->mMonth > gmdate( 'n' ) ) {
 630                                 $year--;
 631                         }
 632                 }
 633                 if ( $this->mMonth ) {
 634                         $month = $this->mMonth + 1;
 635                         // For December, we want January 1 of the next year
 636                         if ($month > 12) {
 637                                 $month = 1;
 638                                 $year++;
 639                         }
 640                 } else {
 641                         // No month implies we want up to the end of the year in question
 642                         $month = 1;
 643                         $year++;
 644                 }
 645                 // Y2K38 bug
 646                 if ( $year > 2032 ) {
 647                         $year = 2032;
 648                 }
 649                 $ymd = (int)sprintf( "%04d%02d01", $year, $month );
 650                 if ( $ymd > 20320101 ) {
 651                         $ymd = 20320101;
 652                 }
 653                 $this->mOffset = $this->mDb->timestamp( "${ymd}000000" );
 654         }
 655 }
 656
 657 /**
 658  * Table-based display with a user-selectable sort order
 659  * @ingroup Pager
 660  */
 661 abstract class TablePager extends IndexPager {
 662         var $mSort;
 663         var $mCurrentRow;
 664
 665         function __construct() {
 666                 global $wgRequest;
 667                 $this->mSort = $wgRequest->getText( 'sort' );
 668                 if ( !array_key_exists( $this->mSort, $this->getFieldNames() ) ) {
 669                         $this->mSort = $this->getDefaultSort();
 670                 }
 671                 if ( $wgRequest->getBool( 'asc' ) ) {
 672                         $this->mDefaultDirection = false;
 673                 } elseif ( $wgRequest->getBool( 'desc' ) ) {
 674                         $this->mDefaultDirection = true;
 675                 } /* Else leave it at whatever the class default is */
 676
 677                 parent::__construct();
 678         }
 679
 680         function getStartBody() {
 681                 global $wgStylePath;
 682                 $tableClass = htmlspecialchars( $this->getTableClass() );
 683                 $sortClass = htmlspecialchars( $this->getSortHeaderClass() );
 684
 685                 $s = "<table border='1' class=\"$tableClass\"><thead><tr>\n";
 686                 $fields = $this->getFieldNames();
 687
 688                 # Make table header
 689                 foreach ( $fields as $field => $name ) {
 690                         if ( strval( $name ) == '' ) {
 691                                 $s .= "<th>&nbsp;</th>\n";
 692                         } elseif ( $this->isFieldSortable( $field ) ) {
 693                                 $query = array( 'sort' => $field, 'limit' => $this->mLimit );
 694                                 if ( $field == $this->mSort ) {
 695                                         # This is the sorted column
 696                                         # Prepare a link that goes in the other sort order
 697                                         if ( $this->mDefaultDirection ) {
 698                                                 # Descending
 699                                                 $image = 'Arr_u.png';
 700                                                 $query['asc'] = '1';
 701                                                 $query['desc'] = '';
 702                                                 $alt = htmlspecialchars( wfMsg( 'descending_abbrev' ) );
 703                                         } else {
 704                                                 # Ascending
 705                                                 $image = 'Arr_d.png';
 706                                                 $query['asc'] = '';
 707                                                 $query['desc'] = '1';
 708                                                 $alt = htmlspecialchars( wfMsg( 'ascending_abbrev' ) );
 709                                         }
 710                                         $image = htmlspecialchars( "$wgStylePath/common/images/$image" );
 711                                         $link = $this->makeLink(
 712                                                 "<img width=\"12\" height=\"12\" alt=\"$alt\" src=\"$image\" />" .
 713                                                 htmlspecialchars( $name ), $query );
 714                                         $s .= "<th class=\"$sortClass\">$link</th>\n";
 715                                 } else {
 716                                         $s .= '<th>' . $this->makeLink( htmlspecialchars( $name ), $query ) . "</th>\n";
 717                                 }
 718                         } else {
 719                                 $s .= '<th>' . htmlspecialchars( $name ) . "</th>\n";
 720                         }
 721                 }
 722                 $s .= "</tr></thead><tbody>\n";
 723                 return $s;
 724         }
 725
 726         function getEndBody() {
 727                 return "</tbody></table>\n";
 728         }
 729
 730         function getEmptyBody() {
 731                 $colspan = count( $this->getFieldNames() );
 732                 $msgEmpty = wfMsgHtml( 'table_pager_empty' );
 733                 return "<tr><td colspan=\"$colspan\">$msgEmpty</td></tr>\n";
 734         }
 735
 736         function formatRow( $row ) {
 737                 $s = "<tr>\n";
 738                 $fieldNames = $this->getFieldNames();
 739                 $this->mCurrentRow = $row;  # In case formatValue needs to know
 740                 foreach ( $fieldNames as $field => $name ) {
 741                         $value = isset( $row->$field ) ? $row->$field : null;
 742                         $formatted = strval( $this->formatValue( $field, $value ) );
 743                         if ( $formatted == '' ) {
 744                                 $formatted = '&nbsp;';
 745                         }
 746                         $class = 'TablePager_col_' . htmlspecialchars( $field );
 747                         $s .= "<td class=\"$class\">$formatted</td>\n";
 748                 }
 749                 $s .= "</tr>\n";
 750                 return $s;
 751         }
 752
 753         function getIndexField() {
 754                 return $this->mSort;
 755         }
 756
 757         function getTableClass() {
 758                 return 'TablePager';
 759         }
 760
 761         function getNavClass() {
 762                 return 'TablePager_nav';
 763         }
 764
 765         function getSortHeaderClass() {
 766                 return 'TablePager_sort';
 767         }
 768
 769         /**
 770          * A navigation bar with images
 771          */
 772         function getNavigationBar() {
 773                 global $wgStylePath, $wgContLang;
 774                 $path = "$wgStylePath/common/images";
 775                 $labels = array(
 776                         'first' => 'table_pager_first',
 777                         'prev' => 'table_pager_prev',
 778                         'next' => 'table_pager_next',
 779                         'last' => 'table_pager_last',
 780                 );
 781                 $images = array(
 782                         'first' => $wgContLang->isRTL() ? 'arrow_last_25.png' : 'arrow_first_25.png',
 783                         'prev' =>  $wgContLang->isRTL() ? 'arrow_right_25.png' : 'arrow_left_25.png',
 784                         'next' =>  $wgContLang->isRTL() ? 'arrow_left_25.png' : 'arrow_right_25.png',
 785                         'last' =>  $wgContLang->isRTL() ? 'arrow_first_25.png' : 'arrow_last_25.png',
 786                 );
 787                 $disabledImages = array(
 788                         'first' => $wgContLang->isRTL() ? 'arrow_disabled_last_25.png' : 'arrow_disabled_first_25.png',
 789                         'prev' =>  $wgContLang->isRTL() ? 'arrow_disabled_right_25.png' : 'arrow_disabled_left_25.png',
 790                         'next' =>  $wgContLang->isRTL() ? 'arrow_disabled_left_25.png' : 'arrow_disabled_right_25.png',
 791                         'last' =>  $wgContLang->isRTL() ? 'arrow_disabled_first_25.png' : 'arrow_disabled_last_25.png',
 792                 );
 793
 794                 $linkTexts = array();
 795                 $disabledTexts = array();
 796                 foreach ( $labels as $type => $label ) {
 797                         $msgLabel = wfMsgHtml( $label );
 798                         $linkTexts[$type] = "<img src=\"$path/{$images[$type]}\" alt=\"$msgLabel\"/><br/>$msgLabel";
 799                         $disabledTexts[$type] = "<img src=\"$path/{$disabledImages[$type]}\" alt=\"$msgLabel\"/><br/>$msgLabel";
 800                 }
 801                 $links = $this->getPagingLinks( $linkTexts, $disabledTexts );
 802
 803                 $navClass = htmlspecialchars( $this->getNavClass() );
 804                 $s = "<table class=\"$navClass\" align=\"center\" cellpadding=\"3\"><tr>\n";
 805                 $cellAttrs = 'valign="top" align="center" width="' . 100 / count( $links ) . '%"';
 806                 foreach ( $labels as $type => $label ) {
 807                         $s .= "<td $cellAttrs>{$links[$type]}</td>\n";
 808                 }
 809                 $s .= "</tr></table>\n";
 810                 return $s;
 811         }
 812
 813         /**
 814          * Get a <select> element which has options for each of the allowed limits
 815          */
 816         function getLimitSelect() {
 817                 global $wgLang;
 818                 $s = "<select name=\"limit\">";
 819                 foreach ( $this->mLimitsShown as $limit ) {
 820                         $selected = $limit == $this->mLimit ? 'selected="selected"' : '';
 821                         $formattedLimit = $wgLang->formatNum( $limit );
 822                         $s .= "<option value=\"$limit\" $selected>$formattedLimit</option>\n";
 823                 }
 824                 $s .= "</select>";
 825                 return $s;
 826         }
 827
 828         /**
 829          * Get <input type="hidden"> elements for use in a method="get" form.
 830          * Resubmits all defined elements of the $_GET array, except for a
 831          * blacklist, passed in the $blacklist parameter.
 832          */
 833         function getHiddenFields( $blacklist = array() ) {
 834                 $blacklist = (array)$blacklist;
 835                 $query = $_GET;
 836                 foreach ( $blacklist as $name ) {
 837                         unset( $query[$name] );
 838                 }
 839                 $s = '';
 840                 foreach ( $query as $name => $value ) {
 841                         $encName = htmlspecialchars( $name );
 842                         $encValue = htmlspecialchars( $value );
 843                         $s .= "<input type=\"hidden\" name=\"$encName\" value=\"$encValue\"/>\n";
 844                 }
 845                 return $s;
 846         }
 847
 848         /**
 849          * Get a form containing a limit selection dropdown
 850          */
 851         function getLimitForm() {
 852                 # Make the select with some explanatory text
 853                 $url = $this->getTitle()->escapeLocalURL();
 854                 $msgSubmit = wfMsgHtml( 'table_pager_limit_submit' );
 855                 return
 856                         "<form method=\"get\" action=\"$url\">" .
 857                         wfMsgHtml( 'table_pager_limit', $this->getLimitSelect() ) .
 858                         "\n<input type=\"submit\" value=\"$msgSubmit\"/>\n" .
 859                         $this->getHiddenFields( array('limit','title') ) .
 860                         "</form>\n";
 861         }
 862
 863         /**
 864          * Return true if the named field should be sortable by the UI, false
 865          * otherwise
 866          *
 867          * @param string $field
 868          */
 869         abstract function isFieldSortable( $field );
 870
 871         /**
 872          * Format a table cell. The return value should be HTML, but use an empty
 873          * string not &nbsp; for empty cells. Do not include the <td> and </td>.
 874          *
 875          * The current result row is available as $this->mCurrentRow, in case you
 876          * need more context.
 877          *
 878          * @param string $name The database field name
 879          * @param string $value The value retrieved from the database
 880          */
 881         abstract function formatValue( $name, $value );
 882
 883         /**
 884          * The database field name used as a default sort order
 885          */
 886         abstract function getDefaultSort();
 887
 888         /**
 889          * An array mapping database field names to a textual description of the
 890          * field name, for use in the table header. The description should be plain
 891          * text, it will be HTML-escaped later.
 892          */
 893         abstract function getFieldNames();
 894 }