includes/pager/ReverseChronologicalPager.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @ingroup Pager
  20  */
  21 use Wikimedia\Timestamp\TimestampException;
  22
  23 /**
  24  * Efficient paging for SQL queries.
  25  * IndexPager with a formatted navigation bar.
  26  * @ingroup Pager
  27  */
  28 abstract class ReverseChronologicalPager extends IndexPager {
  29         public $mDefaultDirection = IndexPager::DIR_DESCENDING;
  30         public $mYear;
  31         public $mMonth;
  32         public $mDay;
  33
  34         public function getNavigationBar() {
  35                 if ( !$this->isNavigationBarShown() ) {
  36                         return '';
  37                 }
  38
  39                 if ( isset( $this->mNavigationBar ) ) {
  40                         return $this->mNavigationBar;
  41                 }
  42
  43                 $linkTexts = [
  44                         'prev' => $this->msg( 'pager-newer-n' )->numParams( $this->mLimit )->escaped(),
  45                         'next' => $this->msg( 'pager-older-n' )->numParams( $this->mLimit )->escaped(),
  46                         'first' => $this->msg( 'histlast' )->escaped(),
  47                         'last' => $this->msg( 'histfirst' )->escaped()
  48                 ];
  49
  50                 $pagingLinks = $this->getPagingLinks( $linkTexts );
  51                 $limitLinks = $this->getLimitLinks();
  52                 $limits = $this->getLanguage()->pipeList( $limitLinks );
  53                 $firstLastLinks = $this->msg( 'parentheses' )->rawParams( "{$pagingLinks['first']}" .
  54                         $this->msg( 'pipe-separator' )->escaped() .
  55                         "{$pagingLinks['last']}" )->escaped();
  56
  57                 $this->mNavigationBar = $firstLastLinks . ' ' .
  58                         $this->msg( 'viewprevnext' )->rawParams(
  59                                 $pagingLinks['prev'], $pagingLinks['next'], $limits )->escaped();
  60
  61                 return $this->mNavigationBar;
  62         }
  63
  64         /**
  65          * Set and return the mOffset timestamp such that we can get all revisions with
  66          * a timestamp up to the specified parameters.
  67          *
  68          * @param int $year Year up to which we want revisions
  69          * @param int $month Month up to which we want revisions
  70          * @param int $day [optional] Day up to which we want revisions. Default is end of month.
  71          * @return string|null Timestamp or null if year and month are false/invalid
  72          */
  73         public function getDateCond( $year, $month, $day = -1 ) {
  74                 $year = (int)$year;
  75                 $month = (int)$month;
  76                 $day = (int)$day;
  77
  78                 // Basic validity checks for year and month
  79                 // If year and month are invalid, don't update the mOffset
  80                 if ( $year <= 0 && ( $month <= 0 || $month >= 13 ) ) {
  81                         return null;
  82                 }
  83
  84                 $timestamp = self::getOffsetDate( $year, $month, $day );
  85
  86                 try {
  87                         // The timestamp used for DB queries is at midnight of the *next* day after the selected date.
  88                         $selectedDate = new DateTime( $timestamp->getTimestamp( TS_ISO_8601 ) );
  89                         $selectedDate = $selectedDate->modify( '-1 day' );
  90
  91                         $this->mYear = (int)$selectedDate->format( 'Y' );
  92                         $this->mMonth = (int)$selectedDate->format( 'm' );
  93                         $this->mDay = (int)$selectedDate->format( 'd' );
  94                         $this->mOffset = $this->mDb->timestamp( $timestamp->getTimestamp() );
  95                 } catch ( TimestampException $e ) {
  96                         // Invalid user provided timestamp (T149257)
  97                         return null;
  98                 }
  99
 100                 return $this->mOffset;
 101         }
 102
 103         /**
 104          * Core logic of determining the mOffset timestamp such that we can get all items with
 105          * a timestamp up to the specified parameters. Given parameters for a day up to which to get
 106          * items, this function finds the timestamp of the day just after the end of the range for use
 107          * in an database strict inequality filter.
 108          *
 109          * This is separate from getDateCond so we can use this logic in other places, such as in
 110          * RangeChronologicalPager, where this function is used to convert year/month/day filter options
 111          * into a timestamp.
 112          *
 113          * @param int $year Year up to which we want revisions
 114          * @param int $month Month up to which we want revisions
 115          * @param int $day [optional] Day up to which we want revisions. Default is end of month.
 116          * @return MWTimestamp Timestamp or null if year and month are false/invalid
 117          */
 118         public static function getOffsetDate( $year, $month, $day = -1 ) {
 119                 // Given an optional year, month, and day, we need to generate a timestamp
 120                 // to use as "WHERE rev_timestamp <= result"
 121                 // Examples: year = 2006      equals < 20070101 (+000000)
 122                 // year=2005, month=1         equals < 20050201
 123                 // year=2005, month=12        equals < 20060101
 124                 // year=2005, month=12, day=5 equals < 20051206
 125                 if ( $year <= 0 ) {
 126                         // If no year given, assume the current one
 127                         $timestamp = MWTimestamp::getInstance();
 128                         $year = $timestamp->format( 'Y' );
 129                         // If this month hasn't happened yet this year, go back to last year's month
 130                         if ( $month > $timestamp->format( 'n' ) ) {
 131                                 $year--;
 132                         }
 133                 }
 134
 135                 if ( $month && $month > 0 && $month < 13 ) {
 136                         // Day validity check after we have month and year checked
 137                         $day = checkdate( $month, $day, $year ) ? $day : false;
 138
 139                         if ( $day && $day > 0 ) {
 140                                 // If we have a day, we want up to the day immediately afterward
 141                                 $day++;
 142
 143                                 // Did we overflow the current month?
 144                                 if ( !checkdate( $month, $day, $year ) ) {
 145                                         $day = 1;
 146                                         $month++;
 147                                 }
 148                         } else {
 149                                 // If no day, assume beginning of next month
 150                                 $day = 1;
 151                                 $month++;
 152                         }
 153
 154                         // Did we overflow the current year?
 155                         if ( $month > 12 ) {
 156                                 $month = 1;
 157                                 $year++;
 158                         }
 159
 160                 } else {
 161                         // No month implies we want up to the end of the year in question
 162                         $month = 1;
 163                         $day = 1;
 164                         $year++;
 165                 }
 166
 167                 // Y2K38 bug
 168                 if ( $year > 2032 ) {
 169                         $year = 2032;
 170                 }
 171
 172                 $ymd = (int)sprintf( "%04d%02d%02d", $year, $month, $day );
 173
 174                 if ( $ymd > 20320101 ) {
 175                         $ymd = 20320101;
 176                 }
 177
 178                 return MWTimestamp::getInstance( "${ymd}000000" );
 179         }
 180 }