From 161001348a269377507323a0248668e0b620a79a Mon Sep 17 00:00:00 2001
From: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Date: Tue, 13 Oct 2015 10:45:32 +0100
Subject: [PATCH] Bug 12478: Display facet terms ordered by number of
 occurrences

By default ES returns the facet terms ordered by most used, which makes
sense.

This patch removes resort done in the scripts (catalogue/search.pl and
opac/opac-search.pl) and moves it to the module.

For Zebra it's now done in C4::Search::getRecords, and there is no
change to expect (still alphabetically).

On the Elastic search side, we could imagine to let the library define
the order of the facets. The facet terms are now sorted by most used.

To test easily this change, turn on the displayFacetCount pref.
---
 C4/Search.pm                              |  9 +++++++++
 Koha/SearchEngine/Elasticsearch/Search.pm | 24 ++++++++++++++----------
 catalogue/search.pl                       |  6 ------
 opac/opac-search.pl                       |  8 --------
 4 files changed, 23 insertions(+), 24 deletions(-)

diff --git a/C4/Search.pm b/C4/Search.pm
index b3d5554..d312dff 100644
--- a/C4/Search.pm
+++ b/C4/Search.pm
@@ -625,6 +625,15 @@ sub getRecords {
                 }
             }
         );
+
+    # This sorts the facets into alphabetical order
+    if (@facets_loop) {
+        foreach my $f (@facets_loop) {
+            $f->{facets} = [ sort { uc($a->{facet_label_value}) cmp uc($b->{facet_label_value}) } @{ $f->{facets} } ];
+        }
+        @facets_loop = sort {$a->{expand} cmp $b->{expand}} @facets_loop;
+    }
+
     return ( undef, $results_hashref, \@facets_loop );
 }
 
diff --git a/Koha/SearchEngine/Elasticsearch/Search.pm b/Koha/SearchEngine/Elasticsearch/Search.pm
index 35a34f2..61d6491 100644
--- a/Koha/SearchEngine/Elasticsearch/Search.pm
+++ b/Koha/SearchEngine/Elasticsearch/Search.pm
@@ -391,13 +391,14 @@ sub _convert_facets {
 
     # These should correspond to the ES field names, as opposed to the CCL
     # things that zebra uses.
+    # TODO let the library define the order using the interface.
     my %type_to_label = (
-        author   => 'Authors',
-        location => 'Location',
-        itype    => 'ItemTypes',
-        se       => 'Series',
-        subject  => 'Topics',
-        'su-geo' => 'Places',
+        author   => { order => 1, label => 'Authors', },
+        itype    => { order => 2, label => 'ItemTypes', },
+        location => { order => 3, label => 'Location', },
+        'su-geo' => { order => 4, label => 'Places', },
+        se       => { order => 5, label => 'Series', },
+        subject  => { order => 6, label => 'Topics', },
     );
 
     # We also have some special cases, e.g. itypes that need to show the
@@ -409,7 +410,7 @@ sub _convert_facets {
         itype    => { map { $_->itemtype         => $_->description } @itypes },
         location => { map { $_->authorised_value => ( $opac ? ( $_->lib_opac || $_->lib ) : $_->lib ) } @locations },
     );
-    my @res;
+    my @facets;
     $exp_facet //= '';
     while ( ( $type, $data ) = each %$es ) {
         next if !exists( $type_to_label{$type} );
@@ -421,8 +422,9 @@ sub _convert_facets {
             expand     => $type,
             expandable => ( $type ne $exp_facet )
               && ( @{ $data->{terms} } > $limit ),
-            "type_label_$type_to_label{$type}" => 1,
+            "type_label_$type_to_label{$type}{label}" => 1,
             type_link_value                    => $type,
+            order      => $type_to_label{$type}{order},
         };
         $limit = @{ $data->{terms} } if ( $limit > @{ $data->{terms} } );
         foreach my $term ( @{ $data->{terms} }[ 0 .. $limit - 1 ] ) {
@@ -443,9 +445,11 @@ sub _convert_facets {
                 type_link_value => $type,
             };
         }
-        push @res, $facet if exists $facet->{facets};
+        push @facets, $facet if exists $facet->{facets};
     }
-    return \@res;
+
+    @facets = sort { $a->{order} cmp $b->{order} } @facets;
+    return \@facets;
 }
 
 
diff --git a/catalogue/search.pl b/catalogue/search.pl
index a43f970..0b9de4c 100755
--- a/catalogue/search.pl
+++ b/catalogue/search.pl
@@ -484,12 +484,6 @@ eval {
     );
 };
 
-# This sorts the facets into alphabetical order
-if ($facets) {
-    foreach my $f (@$facets) {
-        $f->{facets} = [ sort { uc($a->{facet_label_value}) cmp uc($b->{facet_label_value}) } @{ $f->{facets} } ];
-    }
-}
 if ($@ || $error) {
     $template->param(query_error => $error.$@);
     output_html_with_http_headers $cgi, $cookie, $template->output;
diff --git a/opac/opac-search.pl b/opac/opac-search.pl
index d3d005e..4cfabec 100755
--- a/opac/opac-search.pl
+++ b/opac/opac-search.pl
@@ -589,14 +589,6 @@ if ($tag) {
     };
 }
 
-# This sorts the facets into alphabetical order
-if ($facets && @$facets) {
-    foreach my $f (@$facets) {
-        $f->{facets} = [ sort { uc($a->{facet_label_value}) cmp uc($b->{facet_label_value}) } @{ $f->{facets} } ];
-    }
-    @$facets = sort {$a->{expand} cmp $b->{expand}} @$facets;
-}
-
 # use Data::Dumper; print STDERR "-" x 25, "\n", Dumper($results_hashref);
 if ($@ || $error) {
     $template->param(query_error => $error.$@);
-- 
2.1.0