(bug 12645) File histories should be paged

diff --git a/includes/ImagePage.php b/includes/ImagePage.php
index 0638a5b..8723160 100644 (file)
--- a/includes/ImagePage.php
+++ b/includes/ImagePage.php
@@ -594,20 +594,9 @@ EOT
                global $wgOut, $wgUseExternalEditor;
 
                $this->loadFile();
-               $s = '';
-               if( $this->img->exists() ) {
-                       $list = new ImageHistoryList( $this );
-                       $file = $this->img;
-                       $s = $list->beginImageHistoryList();
-                       $s .= $list->imageHistoryLine( true, $file );
-                       // old image versions
-                       $hist = $this->img->getHistory();
-                       foreach( $hist as $file ) {
-                               $s .= $list->imageHistoryLine( false, $file );
-                       }
-                       $s .= $list->endImageHistoryList();
-               }
-               $wgOut->addHTML( $s );
+               $pager = new ImageHistoryPseudoPager( $this );
+               # Generate prev/next links
+               $wgOut->addHTML( $pager->getBody() );
 
                $this->img->resetHistory(); // free db resources
 
@@ -803,10 +792,11 @@ class ImageHistoryList {
                return $this->img;
        }
 
-       public function beginImageHistoryList() {
+       public function beginImageHistoryList( $navLinks = '' ) {
                global $wgOut, $wgUser;
                return Xml::element( 'h2', array( 'id' => 'filehistory' ), wfMsg( 'filehist' ) )
                        . $wgOut->parse( wfMsgNoTrans( 'filehist-help' ) )
+                       . $navLinks
                        . Xml::openElement( 'table', array( 'class' => 'filehistory' ) ) . "\n"
                        . '<tr><td></td>'
                        . ( $this->current->isLocal() && ($wgUser->isAllowed('delete') || $wgUser->isAllowed('deleterevision') ) ? '<td></td>' : '' )
@@ -818,8 +808,8 @@ class ImageHistoryList {
                        . "</tr>\n";
        }
 
-       public function endImageHistoryList() {
-               return "</table>\n";
+       public function endImageHistoryList( $navLinks = '' ) {
+               return "</table>\n$navLinks\n";
        }
 
        public function imageHistoryLine( $iscur, $file ) {
@@ -966,3 +956,123 @@ class ImageHistoryList {
                return "<tr{$classAttr}>{$row}</tr>\n";
        }
 }
+
+class ImageHistoryPseudoPager extends ReverseChronologicalPager {
+       function __construct( $imagePage ) {
+               parent::__construct();
+               $this->mImagePage =& $imagePage;
+               $this->mTitle = $imagePage->getTitle();
+               $this->mImg = NULL;
+               $this->mHist = array();
+               $this->mRange = array( 0, 0 ); // display range
+       }
+
+       function getQueryInfo() {
+               return false;
+       }
+
+       function getIndexField() {
+               return '';
+       }
+
+       function formatRow( $row ) {
+               return '';
+       }
+       
+       function getBody() {
+               $s = '';
+               $this->doQuery();
+               if( count($this->mHist) ) {
+                       $list = new ImageHistoryList( $this->mImagePage );
+                       # Generate prev/next links
+                       $navLink = $this->getNavigationBar();
+                       $s = $list->beginImageHistoryList($navLink);
+                       // Skip rows there just for paging links
+                       for( $i = $this->mRange[0]; $i <= $this->mRange[1]; $i++ ) {
+                               $file = $this->mHist[$i];
+                               $s .= $list->imageHistoryLine( !$file->isOld(), $file );
+                       }
+                       $s .= $list->endImageHistoryList($navLink);
+               }
+               return $s;
+       }
+
+       function doQuery() {
+               if( $this->mQueryDone ) return;
+               $this->mImg = $this->mImagePage->getFile(); // ensure loading
+               if( !$this->mImg->exists() ) {
+                       return;
+               }
+               $queryLimit = $this->mLimit + 1; // limit plus extra row
+               if( $this->mIsBackwards ) {
+                       // Fetch the file history
+                       $this->mHist = $this->mImg->getHistory($queryLimit,null,$this->mOffset,false);
+                       // The current rev may not meet the offset/limit
+                       $numRows = count($this->mHist);
+                       if( $numRows <= $this->mLimit && $this->mImg->getTimestamp() > $this->mOffset ) {
+                               $this->mHist = array_merge( array($this->mImg), $this->mHist );
+                       }
+               } else {
+                       // The current rev may not meet the offset
+                       if( !$this->mOffset || $this->mImg->getTimestamp() < $this->mOffset ) {
+                               $this->mHist[] = $this->mImg;
+                       }
+                       // Old image versions (fetch extra row for nav links)
+                       $oiLimit = count($this->mHist) ? $this->mLimit : $this->mLimit+1;
+                       // Fetch the file history
+                       $this->mHist = array_merge( $this->mHist,
+                               $this->mImg->getHistory($oiLimit,$this->mOffset,null,false) );
+               }
+               $numRows = count($this->mHist); // Total number of query results
+               if( $numRows ) {
+                       # Index value of top item in the list
+                       $firstIndex = $this->mIsBackwards ?
+                               $this->mHist[$numRows-1]->getTimestamp() : $this->mHist[0]->getTimestamp();
+                       # Discard the extra result row if there is one
+                       if( $numRows > $this->mLimit && $numRows > 1 ) {
+                               if( $this->mIsBackwards ) {
+                                       # Index value of item past the index
+                                       $this->mPastTheEndIndex = $this->mHist[0]->getTimestamp();
+                                       # Index value of bottom item in the list
+                                       $lastIndex = $this->mHist[1]->getTimestamp();
+                                       # Display range
+                                       $this->mRange = array( 1, $numRows-1 );
+                               } else {
+                                       # Index value of item past the index
+                                       $this->mPastTheEndIndex = $this->mHist[$numRows-1]->getTimestamp();
+                                       # Index value of bottom item in the list
+                                       $lastIndex = $this->mHist[$numRows-2]->getTimestamp();
+                                       # Display range
+                                       $this->mRange = array( 0, $numRows-2 );
+                               }
+                       } else {
+                               # Setting indexes to an empty string means that they will be
+                               # omitted if they would otherwise appear in URLs. It just so
+                               # happens that this  is the right thing to do in the standard
+                               # UI, in all the relevant cases.
+                               $this->mPastTheEndIndex = '';
+                               # Index value of bottom item in the list
+                               $lastIndex = $this->mIsBackwards ?
+                                       $this->mHist[0]->getTimestamp() : $this->mHist[$numRows-1]->getTimestamp();
+                               # Display range
+                               $this->mRange = array( 0, $numRows-1 );
+                       }
+               } else {
+                       $firstIndex = '';
+                       $lastIndex = '';
+                       $this->mPastTheEndIndex = '';
+               }
+               if( $this->mIsBackwards ) {
+                       $this->mIsFirst = ( $numRows < $queryLimit );
+                       $this->mIsLast = ( $this->mOffset == '' );
+                       $this->mLastShown = $firstIndex;
+                       $this->mFirstShown = $lastIndex;
+               } else {
+                       $this->mIsFirst = ( $this->mOffset == '' );
+                       $this->mIsLast = ( $numRows < $queryLimit );
+                       $this->mLastShown = $lastIndex;
+                       $this->mFirstShown = $firstIndex;
+               }
+               $this->mQueryDone = true;
+       }
+}