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          * Set the offset from an other source than $wgRequest
 167          */
 168         function setOffset( $offset ) {
 169                 $this->mOffset = $offset;
 170         }
 171         /**
 172          * Set the limit from an other source than $wgRequest
 173          */
 174         function setLimit( $limit ) {
 175                 $this->mLimit = $limit;
 176         }
 177
 178         /**
 179          * Extract some useful data from the result object for use by
 180          * the navigation bar, put it into $this
 181          */
 182         function extractResultInfo( $offset, $limit, ResultWrapper $res ) {
 183                 $numRows = $res->numRows();
 184                 if ( $numRows ) {
 185                         $row = $res->fetchRow();
 186                         $firstIndex = $row[$this->mIndexField];
 187
 188                         # Discard the extra result row if there is one
 189                         if ( $numRows > $this->mLimit && $numRows > 1 ) {
 190                                 $res->seek( $numRows - 1 );
 191                                 $this->mPastTheEndRow = $res->fetchObject();
 192                                 $indexField = $this->mIndexField;
 193                                 $this->mPastTheEndIndex = $this->mPastTheEndRow->$indexField;
 194                                 $res->seek( $numRows - 2 );
 195                                 $row = $res->fetchRow();
 196                                 $lastIndex = $row[$this->mIndexField];
 197                         } else {
 198                                 $this->mPastTheEndRow = null;
 199                                 # Setting indexes to an empty string means that they will be
 200                                 # omitted if they would otherwise appear in URLs. It just so
 201                                 # happens that this  is the right thing to do in the standard
 202                                 # UI, in all the relevant cases.
 203                                 $this->mPastTheEndIndex = '';
 204                                 $res->seek( $numRows - 1 );
 205                                 $row = $res->fetchRow();
 206                                 $lastIndex = $row[$this->mIndexField];
 207                         }
 208                 } else {
 209                         $firstIndex = '';
 210                         $lastIndex = '';
 211                         $this->mPastTheEndRow = null;
 212                         $this->mPastTheEndIndex = '';
 213                 }
 214
 215                 if ( $this->mIsBackwards ) {
 216                         $this->mIsFirst = ( $numRows < $limit );
 217                         $this->mIsLast = ( $offset == '' );
 218                         $this->mLastShown = $firstIndex;
 219                         $this->mFirstShown = $lastIndex;
 220                 } else {
 221                         $this->mIsFirst = ( $offset == '' );
 222                         $this->mIsLast = ( $numRows < $limit );
 223                         $this->mLastShown = $lastIndex;
 224                         $this->mFirstShown = $firstIndex;
 225                 }
 226         }
 227
 228         /**
 229          * Do a query with specified parameters, rather than using the object
 230          * context
 231          *
 232          * @param string $offset Index offset, inclusive
 233          * @param integer $limit Exact query limit
 234          * @param boolean $descending Query direction, false for ascending, true for descending
 235          * @return ResultWrapper
 236          */
 237         function reallyDoQuery( $offset, $limit, $descending ) {
 238                 $fname = __METHOD__ . ' (' . get_class( $this ) . ')';
 239                 $info = $this->getQueryInfo();
 240                 $tables = $info['tables'];
 241                 $fields = $info['fields'];
 242                 $conds = isset( $info['conds'] ) ? $info['conds'] : array();
 243                 $options = isset( $info['options'] ) ? $info['options'] : array();
 244                 $join_conds = isset( $info['join_conds'] ) ? $info['join_conds'] : array();
 245                 if ( $descending ) {
 246                         $options['ORDER BY'] = $this->mIndexField;
 247                         $operator = '>';
 248                 } else {
 249                         $options['ORDER BY'] = $this->mIndexField . ' DESC';
 250                         $operator = '<';
 251                 }
 252                 if ( $offset != '' ) {
 253                         $conds[] = $this->mIndexField . $operator . $this->mDb->addQuotes( $offset );
 254                 }
 255                 $options['LIMIT'] = intval( $limit );
 256                 $res = $this->mDb->select( $tables, $fields, $conds, $fname, $options, $join_conds );
 257                 return new ResultWrapper( $this->mDb, $res );
 258         }
 259
 260         /**
 261          * Pre-process results; useful for performing batch existence checks, etc.
 262          *
 263          * @param ResultWrapper $result Result wrapper
 264          */
 265         protected function preprocessResults( $result ) {}
 266
 267         /**
 268          * Get the formatted result list. Calls getStartBody(), formatRow() and
 269          * getEndBody(), concatenates the results and returns them.
 270          */
 271         function getBody() {
 272                 if ( !$this->mQueryDone ) {
 273                         $this->doQuery();
 274                 }
 275                 # Don't use any extra rows returned by the query
 276                 $numRows = min( $this->mResult->numRows(), $this->mLimit );
 277
 278                 $s = $this->getStartBody();
 279                 if ( $numRows ) {
 280                         if ( $this->mIsBackwards ) {
 281                                 for ( $i = $numRows - 1; $i >= 0; $i-- ) {
 282                                         $this->mResult->seek( $i );
 283                                         $row = $this->mResult->fetchObject();
 284                                         $s .= $this->formatRow( $row );
 285                                 }
 286                         } else {
 287                                 $this->mResult->seek( 0 );
 288                                 for ( $i = 0; $i < $numRows; $i++ ) {
 289                                         $row = $this->mResult->fetchObject();
 290                                         $s .= $this->formatRow( $row );
 291                                 }
 292                         }
 293                 } else {
 294                         $s .= $this->getEmptyBody();
 295                 }
 296                 $s .= $this->getEndBody();
 297                 return $s;
 298         }
 299
 300         /**
 301          * Make a self-link
 302          */
 303         function makeLink($text, $query = null, $type=null) {
 304                 if ( $query === null ) {
 305                         return $text;
 306                 }
 307                 if( $type == 'prev' || $type == 'next' ) {
 308                         $attrs = "rel=\"$type\"";
 309                 } elseif( $type == 'first' ) {
 310                         $attrs = "rel=\"start\"";
 311                 } else {
 312                         # HTML 4 has no rel="end" . . .
 313                         $attrs = '';
 314                 }
 315
 316                 if( $type ) {
 317                         $attrs .= " class=\"mw-{$type}link\"" ;
 318                 }
 319                 return $this->getSkin()->makeKnownLinkObj( $this->getTitle(), $text,
 320                         wfArrayToCGI( $query, $this->getDefaultQuery() ), '', '', $attrs );
 321         }
 322
 323         /**
 324          * Hook into getBody(), allows text to be inserted at the start. This
 325          * will be called even if there are no rows in the result set.
 326          */
 327         function getStartBody() {
 328                 return '';
 329         }
 330
 331         /**
 332          * Hook into getBody() for the end of the list
 333          */
 334         function getEndBody() {
 335                 return '';
 336         }
 337
 338         /**
 339          * Hook into getBody(), for the bit between the start and the
 340          * end when there are no rows
 341          */
 342         function getEmptyBody() {
 343                 return '';
 344         }
 345
 346         /**
 347          * Title used for self-links. Override this if you want to be able to
 348          * use a title other than $wgTitle
 349          */
 350         function getTitle() {
 351                 return $GLOBALS['wgTitle'];
 352         }
 353
 354         /**
 355          * Get the current skin. This can be overridden if necessary.
 356          */
 357         function getSkin() {
 358                 if ( !isset( $this->mSkin ) ) {
 359                         global $wgUser;
 360                         $this->mSkin = $wgUser->getSkin();
 361                 }
 362                 return $this->mSkin;
 363         }
 364
 365         /**
 366          * Get an array of query parameters that should be put into self-links.
 367          * By default, all parameters passed in the URL are used, except for a
 368          * short blacklist.
 369          */
 370         function getDefaultQuery() {
 371                 if ( !isset( $this->mDefaultQuery ) ) {
 372                         $this->mDefaultQuery = $_GET;
 373                         unset( $this->mDefaultQuery['title'] );
 374                         unset( $this->mDefaultQuery['dir'] );
 375                         unset( $this->mDefaultQuery['offset'] );
 376                         unset( $this->mDefaultQuery['limit'] );
 377                         unset( $this->mDefaultQuery['order'] );
 378                         unset( $this->mDefaultQuery['month'] );
 379                         unset( $this->mDefaultQuery['year'] );
 380                 }
 381                 return $this->mDefaultQuery;
 382         }
 383
 384         /**
 385          * Get the number of rows in the result set
 386          */
 387         function getNumRows() {
 388                 if ( !$this->mQueryDone ) {
 389                         $this->doQuery();
 390                 }
 391                 return $this->mResult->numRows();
 392         }
 393
 394         /**
 395          * Get a URL query array for the prev, next, first and last links.
 396          */
 397         function getPagingQueries() {
 398                 if ( !$this->mQueryDone ) {
 399                         $this->doQuery();
 400                 }
 401
 402                 # Don't announce the limit everywhere if it's the default
 403                 $urlLimit = $this->mLimit == $this->mDefaultLimit ? '' : $this->mLimit;
 404
 405                 if ( $this->mIsFirst ) {
 406                         $prev = false;
 407                         $first = false;
 408                 } else {
 409                         $prev = array( 'dir' => 'prev', 'offset' => $this->mFirstShown, 'limit' => $urlLimit );
 410                         $first = array( 'limit' => $urlLimit );
 411                 }
 412                 if ( $this->mIsLast ) {
 413                         $next = false;
 414                         $last = false;
 415                 } else {
 416                         $next = array( 'offset' => $this->mLastShown, 'limit' => $urlLimit );
 417                         $last = array( 'dir' => 'prev', 'limit' => $urlLimit );
 418                 }
 419                 return array( 'prev' => $prev, 'next' => $next, 'first' => $first, 'last' => $last );
 420         }
 421
 422         /**
 423          * Get paging links. If a link is disabled, the item from $disabledTexts
 424          * will be used. If there is no such item, the unlinked text from
 425          * $linkTexts will be used. Both $linkTexts and $disabledTexts are arrays
 426          * of HTML.
 427          */
 428         function getPagingLinks( $linkTexts, $disabledTexts = array() ) {
 429                 $queries = $this->getPagingQueries();
 430                 $links = array();
 431                 foreach ( $queries as $type => $query ) {
 432                         if ( $query !== false ) {
 433                                 $links[$type] = $this->makeLink( $linkTexts[$type], $queries[$type], $type );
 434                         } elseif ( isset( $disabledTexts[$type] ) ) {
 435                                 $links[$type] = $disabledTexts[$type];
 436                         } else {
 437                                 $links[$type] = $linkTexts[$type];
 438                         }
 439                 }
 440                 return $links;
 441         }
 442
 443         function getLimitLinks() {
 444                 global $wgLang;
 445                 $links = array();
 446                 if ( $this->mIsBackwards ) {
 447                         $offset = $this->mPastTheEndIndex;
 448                 } else {
 449                         $offset = $this->mOffset;
 450                 }
 451                 foreach ( $this->mLimitsShown as $limit ) {
 452                         $links[] = $this->makeLink( $wgLang->formatNum( $limit ),
 453                                 array( 'offset' => $offset, 'limit' => $limit ), 'num' );
 454                 }
 455                 return $links;
 456         }
 457
 458         /**
 459          * Abstract formatting function. This should return an HTML string
 460          * representing the result row $row. Rows will be concatenated and
 461          * returned by getBody()
 462          */
 463         abstract function formatRow( $row );
 464
 465         /**
 466          * This function should be overridden to provide all parameters
 467          * needed for the main paged query. It returns an associative
 468          * array with the following elements:
 469          *    tables => Table(s) for passing to Database::select()
 470          *    fields => Field(s) for passing to Database::select(), may be *
 471          *    conds => WHERE conditions
 472          *    options => option array
 473          */
 474         abstract function getQueryInfo();
 475
 476         /**
 477          * This function should be overridden to return the name of the index fi-
 478          * eld.  If the pager supports multiple orders, it may return an array of
 479          * 'querykey' => 'indexfield' pairs, so that a request with &count=querykey
 480          * will use indexfield to sort.  In this case, the first returned key is
 481          * the default.
 482          *
 483          * Needless to say, it's really not a good idea to use a non-unique index
 484          * for this!  That won't page right.
 485          */
 486         abstract function getIndexField();
 487
 488         /**
 489          * Return the default sorting direction: false for ascending, true for de-
 490          * scending.  You can also have an associative array of ordertype => dir,
 491          * if multiple order types are supported.  In this case getIndexField()
 492          * must return an array, and the keys of that must exactly match the keys
 493          * of this.
 494          *
 495          * For backward compatibility, this method's return value will be ignored
 496          * if $this->mDefaultDirection is already set when the constructor is
 497          * called, for instance if it's statically initialized.  In that case the
 498          * value of that variable (which must be a boolean) will be used.
 499          *
 500          * Note that despite its name, this does not return the value of the
 501          * $this->mDefaultDirection member variable.  That's the default for this
 502          * particular instantiation, which is a single value.  This is the set of
 503          * all defaults for the class.
 504          */
 505         protected function getDefaultDirections() { return false; }
 506 }
 507
 508
 509 /**
 510  * IndexPager with an alphabetic list and a formatted navigation bar
 511  * @ingroup Pager
 512  */
 513 abstract class AlphabeticPager extends IndexPager {
 514         /**
 515          * Shamelessly stolen bits from ReverseChronologicalPager,
 516          * didn't want to do class magic as may be still revamped
 517          */
 518         function getNavigationBar() {
 519                 global $wgLang;
 520
 521                 if( isset( $this->mNavigationBar ) ) {
 522                         return $this->mNavigationBar;
 523                 }
 524
 525                 $opts = array( 'parsemag', 'escapenoentities' );
 526                 $linkTexts = array(
 527                         'prev' => wfMsgExt( 'prevn', $opts, $wgLang->formatNum( $this->mLimit ) ),
 528                         'next' => wfMsgExt( 'nextn', $opts, $wgLang->formatNum($this->mLimit ) ),
 529                         'first' => wfMsgExt( 'page_first', $opts ),
 530                         'last' => wfMsgExt( 'page_last', $opts )
 531                 );
 532
 533                 $pagingLinks = $this->getPagingLinks( $linkTexts );
 534                 $limitLinks = $this->getLimitLinks();
 535                 $limits = implode( ' | ', $limitLinks );
 536
 537                 $this->mNavigationBar =
 538                         "({$pagingLinks['first']} | {$pagingLinks['last']}) " .
 539                         wfMsgHtml( 'viewprevnext', $pagingLinks['prev'],
 540                         $pagingLinks['next'], $limits );
 541
 542                 if( !is_array( $this->getIndexField() ) ) {
 543                         # Early return to avoid undue nesting
 544                         return $this->mNavigationBar;
 545                 }
 546
 547                 $extra = '';
 548                 $first = true;
 549                 $msgs = $this->getOrderTypeMessages();
 550                 foreach( array_keys( $msgs ) as $order ) {
 551                         if( $first ) {
 552                                 $first = false;
 553                         } else {
 554                                 $extra .= ' | ';
 555                         }
 556
 557                         if( $order == $this->mOrderType ) {
 558                                 $extra .= wfMsgHTML( $msgs[$order] );
 559                         } else {
 560                                 $extra .= $this->makeLink(
 561                                         wfMsgHTML( $msgs[$order] ),
 562                                         array( 'order' => $order )
 563                                 );
 564                         }
 565                 }
 566
 567                 if( $extra !== '' ) {
 568                         $this->mNavigationBar .= " ($extra)";
 569                 }
 570
 571                 return $this->mNavigationBar;
 572         }
 573
 574         /**
 575          * If this supports multiple order type messages, give the message key for
 576          * enabling each one in getNavigationBar.  The return type is an associa-
 577          * tive array whose keys must exactly match the keys of the array returned
 578          * by getIndexField(), and whose values are message keys.
 579          * @return array
 580          */
 581         protected function getOrderTypeMessages() {
 582                 return null;
 583         }
 584 }
 585
 586 /**
 587  * IndexPager with a formatted navigation bar
 588  * @ingroup Pager
 589  */
 590 abstract class ReverseChronologicalPager extends IndexPager {
 591         public $mDefaultDirection = true;
 592         public $mYear;
 593         public $mMonth;
 594
 595         function __construct() {
 596                 parent::__construct();
 597         }
 598
 599         function getNavigationBar() {
 600                 global $wgLang;
 601
 602                 if ( isset( $this->mNavigationBar ) ) {
 603                         return $this->mNavigationBar;
 604                 }
 605                 $nicenumber = $wgLang->formatNum( $this->mLimit );
 606                 $linkTexts = array(
 607                         'prev' => wfMsgExt( 'pager-newer-n', array( 'parsemag' ), $nicenumber ),
 608                         'next' => wfMsgExt( 'pager-older-n', array( 'parsemag' ), $nicenumber ),
 609                         'first' => wfMsgHtml( 'histlast' ),
 610                         'last' => wfMsgHtml( 'histfirst' )
 611                 );
 612
 613                 $pagingLinks = $this->getPagingLinks( $linkTexts );
 614                 $limitLinks = $this->getLimitLinks();
 615                 $limits = implode( ' | ', $limitLinks );
 616
 617                 $this->mNavigationBar = "({$pagingLinks['first']} | {$pagingLinks['last']}) " .
 618                         wfMsgHtml("viewprevnext", $pagingLinks['prev'], $pagingLinks['next'], $limits);
 619                 return $this->mNavigationBar;
 620         }
 621
 622         function getDateCond( $year, $month ) {
 623                 $year = intval($year);
 624                 $month = intval($month);
 625                 // Basic validity checks
 626                 $this->mYear = $year > 0 ? $year : false;
 627                 $this->mMonth = ($month > 0 && $month < 13) ? $month : false;
 628                 // Given an optional year and month, we need to generate a timestamp
 629                 // to use as "WHERE rev_timestamp <= result"
 630                 // Examples: year = 2006 equals < 20070101 (+000000)
 631                 // year=2005, month=1    equals < 20050201
 632                 // year=2005, month=12   equals < 20060101
 633                 if ( !$this->mYear && !$this->mMonth ) {
 634                         return;
 635                 }
 636                 if ( $this->mYear ) {
 637                         $year = $this->mYear;
 638                 } else {
 639                         // If no year given, assume the current one
 640                         $year = gmdate( 'Y' );
 641                         // If this month hasn't happened yet this year, go back to last year's month
 642                         if( $this->mMonth > gmdate( 'n' ) ) {
 643                                 $year--;
 644                         }
 645                 }
 646                 if ( $this->mMonth ) {
 647                         $month = $this->mMonth + 1;
 648                         // For December, we want January 1 of the next year
 649                         if ($month > 12) {
 650                                 $month = 1;
 651                                 $year++;
 652                         }
 653                 } else {
 654                         // No month implies we want up to the end of the year in question
 655                         $month = 1;
 656                         $year++;
 657                 }
 658                 // Y2K38 bug
 659                 if ( $year > 2032 ) {
 660                         $year = 2032;
 661                 }
 662                 $ymd = (int)sprintf( "%04d%02d01", $year, $month );
 663                 if ( $ymd > 20320101 ) {
 664                         $ymd = 20320101;
 665                 }
 666                 $this->mOffset = $this->mDb->timestamp( "${ymd}000000" );
 667         }
 668 }
 669
 670 /**
 671  * Table-based display with a user-selectable sort order
 672  * @ingroup Pager
 673  */
 674 abstract class TablePager extends IndexPager {
 675         var $mSort;
 676         var $mCurrentRow;
 677
 678         function __construct() {
 679                 global $wgRequest;
 680                 $this->mSort = $wgRequest->getText( 'sort' );
 681                 if ( !array_key_exists( $this->mSort, $this->getFieldNames() ) ) {
 682                         $this->mSort = $this->getDefaultSort();
 683                 }
 684                 if ( $wgRequest->getBool( 'asc' ) ) {
 685                         $this->mDefaultDirection = false;
 686                 } elseif ( $wgRequest->getBool( 'desc' ) ) {
 687                         $this->mDefaultDirection = true;
 688                 } /* Else leave it at whatever the class default is */
 689
 690                 parent::__construct();
 691         }
 692
 693         function getStartBody() {
 694                 global $wgStylePath;
 695                 $tableClass = htmlspecialchars( $this->getTableClass() );
 696                 $sortClass = htmlspecialchars( $this->getSortHeaderClass() );
 697
 698                 $s = "<table border='1' class=\"$tableClass\"><thead><tr>\n";
 699                 $fields = $this->getFieldNames();
 700
 701                 # Make table header
 702                 foreach ( $fields as $field => $name ) {
 703                         if ( strval( $name ) == '' ) {
 704                                 $s .= "<th>&nbsp;</th>\n";
 705                         } elseif ( $this->isFieldSortable( $field ) ) {
 706                                 $query = array( 'sort' => $field, 'limit' => $this->mLimit );
 707                                 if ( $field == $this->mSort ) {
 708                                         # This is the sorted column
 709                                         # Prepare a link that goes in the other sort order
 710                                         if ( $this->mDefaultDirection ) {
 711                                                 # Descending
 712                                                 $image = 'Arr_u.png';
 713                                                 $query['asc'] = '1';
 714                                                 $query['desc'] = '';
 715                                                 $alt = htmlspecialchars( wfMsg( 'descending_abbrev' ) );
 716                                         } else {
 717                                                 # Ascending
 718                                                 $image = 'Arr_d.png';
 719                                                 $query['asc'] = '';
 720                                                 $query['desc'] = '1';
 721                                                 $alt = htmlspecialchars( wfMsg( 'ascending_abbrev' ) );
 722                                         }
 723                                         $image = htmlspecialchars( "$wgStylePath/common/images/$image" );
 724                                         $link = $this->makeLink(
 725                                                 "<img width=\"12\" height=\"12\" alt=\"$alt\" src=\"$image\" />" .
 726                                                 htmlspecialchars( $name ), $query );
 727                                         $s .= "<th class=\"$sortClass\">$link</th>\n";
 728                                 } else {
 729                                         $s .= '<th>' . $this->makeLink( htmlspecialchars( $name ), $query ) . "</th>\n";
 730                                 }
 731                         } else {
 732                                 $s .= '<th>' . htmlspecialchars( $name ) . "</th>\n";
 733                         }
 734                 }
 735                 $s .= "</tr></thead><tbody>\n";
 736                 return $s;
 737         }
 738
 739         function getEndBody() {
 740                 return "</tbody></table>\n";
 741         }
 742
 743         function getEmptyBody() {
 744                 $colspan = count( $this->getFieldNames() );
 745                 $msgEmpty = wfMsgHtml( 'table_pager_empty' );
 746                 return "<tr><td colspan=\"$colspan\">$msgEmpty</td></tr>\n";
 747         }
 748
 749         function formatRow( $row ) {
 750                 $s = "<tr>\n";
 751                 $fieldNames = $this->getFieldNames();
 752                 $this->mCurrentRow = $row;  # In case formatValue needs to know
 753                 foreach ( $fieldNames as $field => $name ) {
 754                         $value = isset( $row->$field ) ? $row->$field : null;
 755                         $formatted = strval( $this->formatValue( $field, $value ) );
 756                         if ( $formatted == '' ) {
 757                                 $formatted = '&nbsp;';
 758                         }
 759                         $class = 'TablePager_col_' . htmlspecialchars( $field );
 760                         $s .= "<td class=\"$class\">$formatted</td>\n";
 761                 }
 762                 $s .= "</tr>\n";
 763                 return $s;
 764         }
 765
 766         function getIndexField() {
 767                 return $this->mSort;
 768         }
 769
 770         function getTableClass() {
 771                 return 'TablePager';
 772         }
 773
 774         function getNavClass() {
 775                 return 'TablePager_nav';
 776         }
 777
 778         function getSortHeaderClass() {
 779                 return 'TablePager_sort';
 780         }
 781
 782         /**
 783          * A navigation bar with images
 784          */
 785         function getNavigationBar() {
 786                 global $wgStylePath, $wgContLang;
 787                 $path = "$wgStylePath/common/images";
 788                 $labels = array(
 789                         'first' => 'table_pager_first',
 790                         'prev' => 'table_pager_prev',
 791                         'next' => 'table_pager_next',
 792                         'last' => 'table_pager_last',
 793                 );
 794                 $images = array(
 795                         'first' => $wgContLang->isRTL() ? 'arrow_last_25.png' : 'arrow_first_25.png',
 796                         'prev' =>  $wgContLang->isRTL() ? 'arrow_right_25.png' : 'arrow_left_25.png',
 797                         'next' =>  $wgContLang->isRTL() ? 'arrow_left_25.png' : 'arrow_right_25.png',
 798                         'last' =>  $wgContLang->isRTL() ? 'arrow_first_25.png' : 'arrow_last_25.png',
 799                 );
 800                 $disabledImages = array(
 801                         'first' => $wgContLang->isRTL() ? 'arrow_disabled_last_25.png' : 'arrow_disabled_first_25.png',
 802                         'prev' =>  $wgContLang->isRTL() ? 'arrow_disabled_right_25.png' : 'arrow_disabled_left_25.png',
 803                         'next' =>  $wgContLang->isRTL() ? 'arrow_disabled_left_25.png' : 'arrow_disabled_right_25.png',
 804                         'last' =>  $wgContLang->isRTL() ? 'arrow_disabled_first_25.png' : 'arrow_disabled_last_25.png',
 805                 );
 806
 807                 $linkTexts = array();
 808                 $disabledTexts = array();
 809                 foreach ( $labels as $type => $label ) {
 810                         $msgLabel = wfMsgHtml( $label );
 811                         $linkTexts[$type] = "<img src=\"$path/{$images[$type]}\" alt=\"$msgLabel\"/><br/>$msgLabel";
 812                         $disabledTexts[$type] = "<img src=\"$path/{$disabledImages[$type]}\" alt=\"$msgLabel\"/><br/>$msgLabel";
 813                 }
 814                 $links = $this->getPagingLinks( $linkTexts, $disabledTexts );
 815
 816                 $navClass = htmlspecialchars( $this->getNavClass() );
 817                 $s = "<table class=\"$navClass\" align=\"center\" cellpadding=\"3\"><tr>\n";
 818                 $cellAttrs = 'valign="top" align="center" width="' . 100 / count( $links ) . '%"';
 819                 foreach ( $labels as $type => $label ) {
 820                         $s .= "<td $cellAttrs>{$links[$type]}</td>\n";
 821                 }
 822                 $s .= "</tr></table>\n";
 823                 return $s;
 824         }
 825
 826         /**
 827          * Get a <select> element which has options for each of the allowed limits
 828          */
 829         function getLimitSelect() {
 830                 global $wgLang;
 831                 $s = "<select name=\"limit\">";
 832                 foreach ( $this->mLimitsShown as $limit ) {
 833                         $selected = $limit == $this->mLimit ? 'selected="selected"' : '';
 834                         $formattedLimit = $wgLang->formatNum( $limit );
 835                         $s .= "<option value=\"$limit\" $selected>$formattedLimit</option>\n";
 836                 }
 837                 $s .= "</select>";
 838                 return $s;
 839         }
 840
 841         /**
 842          * Get <input type="hidden"> elements for use in a method="get" form.
 843          * Resubmits all defined elements of the $_GET array, except for a
 844          * blacklist, passed in the $blacklist parameter.
 845          */
 846         function getHiddenFields( $blacklist = array() ) {
 847                 $blacklist = (array)$blacklist;
 848                 $query = $_GET;
 849                 foreach ( $blacklist as $name ) {
 850                         unset( $query[$name] );
 851                 }
 852                 $s = '';
 853                 foreach ( $query as $name => $value ) {
 854                         $encName = htmlspecialchars( $name );
 855                         $encValue = htmlspecialchars( $value );
 856                         $s .= "<input type=\"hidden\" name=\"$encName\" value=\"$encValue\"/>\n";
 857                 }
 858                 return $s;
 859         }
 860
 861         /**
 862          * Get a form containing a limit selection dropdown
 863          */
 864         function getLimitForm() {
 865                 # Make the select with some explanatory text
 866                 $url = $this->getTitle()->escapeLocalURL();
 867                 $msgSubmit = wfMsgHtml( 'table_pager_limit_submit' );
 868                 return
 869                         "<form method=\"get\" action=\"$url\">" .
 870                         wfMsgHtml( 'table_pager_limit', $this->getLimitSelect() ) .
 871                         "\n<input type=\"submit\" value=\"$msgSubmit\"/>\n" .
 872                         $this->getHiddenFields( array('limit','title') ) .
 873                         "</form>\n";
 874         }
 875
 876         /**
 877          * Return true if the named field should be sortable by the UI, false
 878          * otherwise
 879          *
 880          * @param string $field
 881          */
 882         abstract function isFieldSortable( $field );
 883
 884         /**
 885          * Format a table cell. The return value should be HTML, but use an empty
 886          * string not &nbsp; for empty cells. Do not include the <td> and </td>.
 887          *
 888          * The current result row is available as $this->mCurrentRow, in case you
 889          * need more context.
 890          *
 891          * @param string $name The database field name
 892          * @param string $value The value retrieved from the database
 893          */
 894         abstract function formatValue( $name, $value );
 895
 896         /**
 897          * The database field name used as a default sort order
 898          */
 899         abstract function getDefaultSort();
 900
 901         /**
 902          * An array mapping database field names to a textual description of the
 903          * field name, for use in the table header. The description should be plain
 904          * text, it will be HTML-escaped later.
 905          */
 906         abstract function getFieldNames();
 907 }