Paginate the three category sections separately

This fully fixes bug 1211.  It might be buggy, and
$wgExperimentalCategorySort sure makes it hackish.  I should definitely
have gone with some kind of branch here.  More testing would be good.
Also, the UI could use improvement (extra ugly next/previous 200 links
in various places).

diff --git a/includes/CategoryPage.php b/includes/CategoryPage.php
index 97a6098..0897fbf 100644 (file)
--- a/includes/CategoryPage.php
+++ b/includes/CategoryPage.php
@@ -51,11 +51,20 @@ class CategoryPage extends Article {
        }
 
        function closeShowCategory() {
-               global $wgOut, $wgRequest;
-               $from = $wgRequest->getVal( 'from' );
-               $until = $wgRequest->getVal( 'until' );
+               global $wgOut, $wgRequest, $wgExperimentalCategorySort;
 
-               $viewer = new CategoryViewer( $this->mTitle, $from, $until );
+               if ( $wgExperimentalCategorySort ) {
+                       $from = $until = array();
+                       foreach ( array( 'page', 'subcat', 'file' ) as $type ) {
+                               $from[$type] = $wgRequest->getVal( "{$type}from" );
+                               $until[$type] = $wgRequest->getVal( "{$type}until" );
+                       }
+               } else {
+                       $from = $wgRequest->getVal( 'from' );
+                       $until = $wgRequest->getVal( 'until' );
+               }
+
+               $viewer = new CategoryViewer( $this->mTitle, $from, $until, $wgRequest->getValues() );
                $wgOut->addHTML( $viewer->getHTML() );
        }
 }
@@ -66,16 +75,19 @@ class CategoryViewer {
                $children, $children_start_char,
                $showGallery, $gallery,
                $skin;
-       /** Category object for this page */
+       # Category object for this page
        private $cat;
+       # The original query array, to be used in generating paging links.
+       private $query;
 
-       function __construct( $title, $from = '', $until = '' ) {
+       function __construct( $title, $from = '', $until = '', $query = array() ) {
                global $wgCategoryPagingLimit;
                $this->title = $title;
                $this->from = $from;
                $this->until = $until;
                $this->limit = $wgCategoryPagingLimit;
                $this->cat = Category::newFromTitle( $title );
+               $this->query = $query;
        }
 
        /**
@@ -194,7 +206,13 @@ class CategoryViewer {
         */
        function addImage( Title $title, $sortkey, $pageLength, $isRedirect = false ) {
                if ( $this->showGallery ) {
-                       if ( $this->flip ) {
+                       global $wgExperimentalCategorySort;
+                       if ( $wgExperimentalCategorySort ) {
+                               $flip = $this->flip['file'];
+                       } else {
+                               $flip = $this->flip;
+                       }
+                       if ( $flip ) {
                                $this->gallery->insert( $title );
                        } else {
                                $this->gallery->add( $title );
@@ -228,66 +246,81 @@ class CategoryViewer {
        }
 
        function finaliseCategoryState() {
-               if ( $this->flip ) {
+               global $wgExperimentalCategorySort;
+               if ( ( !$wgExperimentalCategorySort && $this->flip )
+                 || ( $wgExperimentalCategorySort && $this->flip['subcat'] ) ) {
                        $this->children            = array_reverse( $this->children );
                        $this->children_start_char = array_reverse( $this->children_start_char );
+               }
+               if ( ( !$wgExperimentalCategorySort && $this->flip )
+                 || ( $wgExperimentalCategorySort && $this->flip['page'] ) ) {
                        $this->articles            = array_reverse( $this->articles );
                        $this->articles_start_char = array_reverse( $this->articles_start_char );
                }
        }
 
        function doCategoryQuery() {
-               global $wgExperimentalCategorySort;
+               global $wgExperimentalCategorySort, $wgRequest, $wgContLang;
 
                $dbr = wfGetDB( DB_SLAVE, 'category' );
-               if ( $this->from != '' ) {
-                       $pageCondition = 'cl_sortkey >= ' . $dbr->addQuotes( $this->from );
-                       $this->flip = false;
-               } elseif ( $this->until != '' ) {
-                       $pageCondition = 'cl_sortkey < ' . $dbr->addQuotes( $this->until );
-                       $this->flip = true;
-               } else {
-                       $pageCondition = '1 = 1';
-                       $this->flip = false;
-               }
 
                $tables = array( 'page', 'categorylinks', 'category' );
                $fields = array( 'page_title', 'page_namespace', 'page_len',
                        'page_is_redirect', 'cl_sortkey', 'cat_id', 'cat_title',
                        'cat_subcats', 'cat_pages', 'cat_files' );
                $conds = array( 'cl_to' => $this->title->getDBkey() );
-               $opts = array( 'ORDER BY' => $this->flip ? 'cl_sortkey DESC' :
-                       'cl_sortkey', 'USE INDEX' => array( 'categorylinks' => 'cl_sortkey' ) );
+               $opts = array(
+                       'USE INDEX' => array( 'categorylinks' => 'cl_sortkey' ),
+                       'LIMIT' => $this->limit + 1,
+               );
                $joins = array( 'categorylinks'  => array( 'INNER JOIN', 'cl_from = page_id' ),
                        'category' => array( 'LEFT JOIN', 'cat_title = page_title AND page_namespace = ' . NS_CATEGORY ) );
 
                if ( $wgExperimentalCategorySort ) {
                        # Copy-pasted from below, but that's okay, because the stuff below
                        # will be deleted when this becomes the default.
-                       $count = 0;
-                       $this->nextPage = null;
+                       $this->nextPage = array(
+                               'page' => null,
+                               'subcat' => null,
+                               'file' => null,
+                       );
+                       $this->flip = array( 'page' => false, 'subcat' => false, 'file' => false );
 
                        foreach ( array( 'page', 'subcat', 'file' ) as $type ) {
+                               # Get the sortkeys for start/end, if applicable.  Note that if
+                               # the collation in the database differs from the one
+                               # $wgContLang is using, pagination might go totally haywire.
+                               $extraConds = array( 'cl_type' => $type );
+                               if ( $this->from[$type] !== null ) {
+                                       $extraConds[] = 'cl_sortkey >= '
+                                               . $dbr->addQuotes( $wgContLang->convertToSortkey( $this->from[$type] ) );
+                               } elseif ( $this->until[$type] !== null ) {
+                                       $extraConds[] = 'cl_sortkey < '
+                                               . $dbr->addQuotes( $wgContLang->convertToSortkey( $this->until[$type] ) );
+                                       $this->flip[$type] = true;
+                               }
+
                                $res = $dbr->select(
                                        $tables,
                                        array_merge( $fields, array( 'cl_sortkey_prefix' ) ),
-                                       $conds + array( 'cl_type' => $type ) + ( $type == 'page' ? array( $pageCondition ) : array() ),
+                                       $conds + $extraConds,
                                        __METHOD__,
-                                       $opts + ( $type == 'page' ? array( 'LIMIT' => $this->limit + 1 ) : array() ),
+                                       $opts + array( 'ORDER BY' => $this->flip[$type] ? 'cl_sortkey DESC' : 'cl_sortkey' ),
                                        $joins
                                );
 
+                               $count = 0;
                                foreach ( $res as $row ) {
-                                       if ( $type == 'page' && ++$count > $this->limit ) {
+                                       $title = Title::newFromRow( $row );
+                                       $rawSortkey = $row->cl_sortkey_prefix . $title->getCategorySortkey();
+
+                                       if ( ++$count > $this->limit ) {
                                                # We've reached the one extra which shows that there
                                                # are additional pages to be had. Stop here...
-                                               $this->nextPage = $row->cl_sortkey;
+                                               $this->nextPage[$type] = $rawSortkey;
                                                break;
                                        }
 
-                                       $title = Title::newFromRow( $row );
-                                       $rawSortkey = $row->cl_sortkey_prefix . $title->getCategorySortkey();
-
                                        if ( $title->getNamespace() == NS_CATEGORY ) {
                                                $cat = Category::newFromRow( $row, $title );
                                                $this->addSubcategoryObject( $cat, $rawSortkey, $row->page_len );
@@ -304,12 +337,23 @@ class CategoryViewer {
 
                # Non-$wgExperimentalCategorySort stuff
 
+               if ( $this->from != '' ) {
+                       $pageCondition = 'cl_sortkey >= ' . $dbr->addQuotes( $this->from );
+                       $this->flip = false;
+               } elseif ( $this->until != '' ) {
+                       $pageCondition = 'cl_sortkey < ' . $dbr->addQuotes( $this->until );
+                       $this->flip = true;
+               } else {
+                       $pageCondition = '1 = 1';
+                       $this->flip = false;
+               }
+
                $res = $dbr->select(
                        $tables,
                        $fields,
                        $conds + array( $pageCondition ),
                        __METHOD__,
-                       $opts + array( 'LIMIT' => $this->limit + 1 ),
+                       $opts + array( 'ORDER BY' => $this->flip ? 'cl_sortkey DESC' : 'cl_sortkey' ),
                        $joins
                );
 
@@ -356,7 +400,9 @@ class CategoryViewer {
                        $r .= "<div id=\"mw-subcategories\">\n";
                        $r .= '<h2>' . wfMsg( 'subcategories' ) . "</h2>\n";
                        $r .= $countmsg;
+                       $r .= $this->getSectionPagingLinks( 'subcat' );
                        $r .= $this->formatList( $this->children, $this->children_start_char );
+                       $r .= $this->getSectionPagingLinks( 'subcat' );
                        $r .= "\n</div>";
                }
                return $r;
@@ -380,31 +426,63 @@ class CategoryViewer {
                        $r = "<div id=\"mw-pages\">\n";
                        $r .= '<h2>' . wfMsg( 'category_header', $ti ) . "</h2>\n";
                        $r .= $countmsg;
+                       $r .= $this->getSectionPagingLinks( 'page' );
                        $r .= $this->formatList( $this->articles, $this->articles_start_char );
+                       $r .= $this->getSectionPagingLinks( 'page' );
                        $r .= "\n</div>";
                }
                return $r;
        }
 
        function getImageSection() {
+               $r = '';
                if ( $this->showGallery && ! $this->gallery->isEmpty() ) {
                        $dbcnt = $this->cat->getFileCount();
                        $rescnt = $this->gallery->count();
                        $countmsg = $this->getCountMessage( $rescnt, $dbcnt, 'file' );
 
-                       return "<div id=\"mw-category-media\">\n" .
-                       '<h2>' . wfMsg( 'category-media-header', htmlspecialchars( $this->title->getText() ) ) . "</h2>\n" .
-                       $countmsg . $this->gallery->toHTML() . "\n</div>";
+                       $r .= "<div id=\"mw-category-media\">\n";
+                       $r .= '<h2>' . wfMsg( 'category-media-header', htmlspecialchars( $this->title->getText() ) ) . "</h2>\n";
+                       $r .= $countmsg;
+                       $r .= $this->getSectionPagingLinks( 'file' );
+                       $r .= $this->gallery->toHTML();
+                       $r .= $this->getSectionPagingLinks( 'file' );
+                       $r .= "\n</div>";
+               }
+               return $r;
+       }
+
+       /**
+        * Get the paging links for a section (subcats/pages/files), to go at the top and bottom
+        * of the output.
+        *
+        * @param string $type 'page', 'subcat', or 'file'
+        * @return string HTML output, possibly empty if there are no other pages
+        */
+       private function getSectionPagingLinks( $type ) {
+               global $wgExperimentalCategorySort;
+               if ( !$wgExperimentalCategorySort ) {
+                       return '';
+               }
+               if ( $this->until[$type] !== null ) {
+                       return $this->pagingLinks( $this->nextPage[$type], $this->until[$type], $type );
+               } elseif ( $this->nextPage[$type] !== null || $this->from[$type] !== null ) {
+                       return $this->pagingLinks( $this->from[$type], $this->nextPage[$type], $type );
                } else {
                        return '';
                }
        }
 
        function getCategoryBottom() {
+               global $wgExperimentalCategorySort;
+               if ( $wgExperimentalCategorySort ) {
+                       # We have per-section paging links, no global ones.
+                       return '';
+               }
                if ( $this->until != '' ) {
-                       return $this->pagingLinks( $this->title, $this->nextPage, $this->until, $this->limit );
+                       return $this->pagingLinks( $this->nextPage, $this->until );
                } elseif ( $this->nextPage != '' || $this->from != '' ) {
-                       return $this->pagingLinks( $this->title, $this->from, $this->nextPage, $this->limit );
+                       return $this->pagingLinks( $this->from, $this->nextPage );
                } else {
                        return '';
                }
@@ -514,26 +592,27 @@ class CategoryViewer {
        }
 
        /**
-        * @param $title Title object
-        * @param $first String
-        * @param $last String
-        * @param $limit Int
-        * @param $query Array: additional query options to pass
-        * @return String
-        * @private
+        * Create paging links, as a helper method to getSectionPagingLinks().
+        *
+        * @param $until String The 'until' parameter for the generated URL
+        * @param $from String The 'from' parameter for the genererated URL
+        * @param $type String A prefix for parameters, 'page' or 'subcat' or
+        *     'file'
+        * @return String HTML
         */
-       function pagingLinks( $title, $first, $last, $limit, $query = array() ) {
+       private function pagingLinks( $first, $last, $type = '' ) {
                global $wgLang;
                $sk = $this->getSkin();
-               $limitText = $wgLang->formatNum( $limit );
+               $limitText = $wgLang->formatNum( $this->limit );
 
                $prevLink = wfMsgExt( 'prevn', array( 'escape', 'parsemag' ), $limitText );
 
                if ( $first != '' ) {
-                       $prevQuery = $query;
-                       $prevQuery['until'] = $first;
+                       $prevQuery = $this->query;
+                       $prevQuery["{$type}until"] = $first;
+                       unset( $prevQuery["{$type}from"] );
                        $prevLink = $sk->linkKnown(
-                               $title,
+                               $this->title,
                                $prevLink,
                                array(),
                                $prevQuery
@@ -543,10 +622,11 @@ class CategoryViewer {
                $nextLink = wfMsgExt( 'nextn', array( 'escape', 'parsemag' ), $limitText );
 
                if ( $last != '' ) {
-                       $lastQuery = $query;
-                       $lastQuery['from'] = $last;
+                       $lastQuery = $this->query;
+                       $lastQuery["{$type}from"] = $last;
+                       unset( $lastQuery["{$type}until"] );
                        $nextLink = $sk->linkKnown(
-                               $title,
+                               $this->title,
                                $nextLink,
                                array(),
                                $lastQuery