C4/ShelfBrowser.pm

   1 #!/usr/bin/perl
   2
   3 package C4::ShelfBrowser;
   4
   5 # Copyright 2010 Catalyst IT
   6 #
   7 # This file is part of Koha.
   8 #
   9 # Koha is free software; you can redistribute it and/or modify it
  10 # under the terms of the GNU General Public License as published by
  11 # the Free Software Foundation; either version 3 of the License, or
  12 # (at your option) any later version.
  13 #
  14 # Koha is distributed in the hope that it will be useful, but
  15 # WITHOUT ANY WARRANTY; without even the implied warranty of
  16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17 # GNU General Public License for more details.
  18 #
  19 # You should have received a copy of the GNU General Public License
  20 # along with Koha; if not, see <http://www.gnu.org/licenses>.
  21
  22 use strict;
  23 use warnings;
  24
  25 use C4::Biblio;
  26 use C4::Context;
  27 use C4::Koha;
  28 use Koha::Biblios;
  29 use Koha::Libraries;
  30
  31 use vars qw(@ISA @EXPORT @EXPORT_OK);
  32
  33 BEGIN {
  34         require Exporter;
  35         @ISA    = qw(Exporter);
  36         @EXPORT = qw(
  37             &GetNearbyItems
  38     );
  39     @EXPORT_OK = qw(
  40     );
  41 }
  42
  43 =head1 NAME
  44
  45 C4::ShelfBrowser - functions that deal with the shelf browser feature found in
  46 the OPAC.
  47
  48 =head1 SYNOPSIS
  49
  50   use C4::ShelfBrowser;
  51
  52 =head1 DESCRIPTION
  53
  54 This module provides functions to get items nearby to another item, for use
  55 in the shelf browser function.
  56
  57 'Nearby' is controlled by a handful of system preferences that specify what
  58 to take into account.
  59
  60 =head1 FUNCTIONS
  61
  62 =head2 GetNearbyItems($itemnumber, [$num_each_side])
  63
  64   $nearby = GetNearbyItems($itemnumber, [$num_each_side]);
  65
  66   @items = @{ $nearby->{items} };
  67
  68   foreach (@items) {
  69       # These won't format well like this, but here are the fields
  70           print $_->{title};
  71           print $_->{biblionumber};
  72           print $_->{itemnumber};
  73           print $_->{browser_normalized_upc};
  74           print $_->{browser_normalized_oclc};
  75           print $_->{browser_normalized_isbn};
  76       print $_->{browser_normalized_ean};
  77   }
  78
  79   # This is the information required to scroll the browser to the next left
  80   # or right set. Can be derived from next/prev, but it's here for convenience.
  81   print $nearby->{prev_item}{itemnumber};
  82   print $nearby->{next_item}{itemnumber};
  83   print $nearby->{prev_item}{biblionumber};
  84   print $nearby->{next_item}{biblionumber};
  85
  86   # These will be undef if the values are not used to calculate the
  87   # nearby items.
  88   print $nearby->{starting_homebranch}->{code};
  89   print $nearby->{starting_homebranch}->{description};
  90   print $nearby->{starting_location}->{code};
  91   print $nearby->{starting_location}->{description};
  92   print $nearby->{starting_ccode}->{code};
  93   print $nearby->{starting_ccode}->{description};
  94
  95 This finds the items that are nearby to the supplied item, and supplies
  96 those previous and next, along with the other useful information for displaying
  97 the shelf browser.
  98
  99 It automatically applies the following user preferences to work out how to
 100 calculate things: C<ShelfBrowserUsesLocation>, C<ShelfBrowserUsesHomeBranch>,
 101 C<ShelfBrowserUsesCcode>.
 102
 103 The option C<$num_each_side> value determines how many items will be fetched
 104 each side of the supplied item. Note that the item itself is the first entry
 105 in the 'next' set, and counts towards this limit (this is to keep the
 106 behaviour consistent with the code that this is a refactor of.) Default is
 107 3.
 108
 109 This will throw an exception if something went wrong.
 110
 111 =cut
 112
 113 sub GetNearbyItems {
 114     my ( $itemnumber, $num_each_side, $gap) = @_;
 115     $num_each_side ||= 3;
 116     $gap ||= 7; # Should be > $num_each_side
 117     die "BAD CALL in C4::ShelfBrowser::GetNearbyItems, gap should be > num_each_side"
 118         if $gap <= $num_each_side;
 119
 120     my $dbh         = C4::Context->dbh;
 121
 122     my $sth_get_item_details = $dbh->prepare("SELECT cn_sort,homebranch,location,ccode from items where itemnumber=?");
 123     $sth_get_item_details->execute($itemnumber);
 124     my $item_details_result = $sth_get_item_details->fetchrow_hashref();
 125     die "Unable to find item '$itemnumber' for shelf browser" if (!$sth_get_item_details);
 126     my $start_cn_sort = $item_details_result->{'cn_sort'};
 127
 128     my ($start_homebranch, $start_location, $start_ccode);
 129     if (C4::Context->preference('ShelfBrowserUsesHomeBranch') &&
 130         defined($item_details_result->{'homebranch'})) {
 131         $start_homebranch->{code} = $item_details_result->{'homebranch'};
 132         $start_homebranch->{description} = Koha::Libraries->find($item_details_result->{'homebranch'})->branchname;
 133     }
 134     if (C4::Context->preference('ShelfBrowserUsesLocation') &&
 135         defined($item_details_result->{'location'})) {
 136         $start_location->{code} = $item_details_result->{'location'};
 137         $start_location->{description} = GetAuthorisedValueDesc('','',$item_details_result->{'location'},'','','LOC','opac');
 138     }
 139     if (C4::Context->preference('ShelfBrowserUsesCcode') &&
 140         defined($item_details_result->{'ccode'})) {
 141         $start_ccode->{code} = $item_details_result->{'ccode'};
 142         $start_ccode->{description} = GetAuthorisedValueDesc('', '', $item_details_result->{'ccode'}, '', '', 'CCODE', 'opac');
 143     }
 144
 145     # Build the query for previous and next items
 146     my $prev_query ='
 147         SELECT itemnumber, biblionumber, cn_sort, itemcallnumber
 148         FROM items
 149         WHERE
 150             ((cn_sort = ? AND itemnumber < ?) OR cn_sort < ?) ';
 151     my $next_query ='
 152         SELECT itemnumber, biblionumber, cn_sort, itemcallnumber
 153         FROM items
 154         WHERE
 155             ((cn_sort = ? AND itemnumber >= ?) OR cn_sort > ?) ';
 156     my @params;
 157     my $query_cond;
 158     push @params, ($start_cn_sort, $itemnumber, $start_cn_sort);
 159     if ($start_homebranch) {
 160         $query_cond .= 'AND homebranch = ? ';
 161         push @params, $start_homebranch->{code};
 162     }
 163     if ($start_location) {
 164         $query_cond .= 'AND location = ? ';
 165         push @params, $start_location->{code};
 166     }
 167     if ($start_ccode) {
 168         $query_cond .= 'AND ccode = ? ';
 169         push @params, $start_ccode->{code};
 170     }
 171
 172     my @prev_items = @{
 173         $dbh->selectall_arrayref(
 174             $prev_query . $query_cond . ' ORDER BY cn_sort DESC, itemnumber DESC LIMIT ?',
 175             { Slice => {} },
 176             ( @params, $gap )
 177         )
 178     };
 179     my @next_items = @{
 180         $dbh->selectall_arrayref(
 181             $next_query . $query_cond . ' ORDER BY cn_sort, itemnumber LIMIT ?',
 182             { Slice => {} },
 183             ( @params, $gap + 1 )
 184         )
 185     };
 186
 187     my $prev_item = $prev_items[-1];
 188     my $next_item = $next_items[-1];
 189     @next_items = splice( @next_items, 0, $num_each_side + 1 );
 190     @prev_items = reverse splice( @prev_items, 0, $num_each_side );
 191     my @items = ( @prev_items, @next_items );
 192
 193     $next_item = undef
 194         if not $next_item
 195             or ( $next_item->{itemnumber} == $items[-1]->{itemnumber}
 196                 and ( @prev_items or @next_items <= 1 )
 197             );
 198     $prev_item = undef
 199         if not $prev_item
 200             or ( $prev_item->{itemnumber} == $items[0]->{itemnumber}
 201                 and ( @next_items or @prev_items <= 1 )
 202             );
 203
 204     # populate the items
 205     @items = GetShelfInfo( @items );
 206
 207     return {
 208         items               => \@items,
 209         next_item           => $next_item,
 210         prev_item           => $prev_item,
 211         starting_homebranch => $start_homebranch,
 212         starting_location   => $start_location,
 213         starting_ccode      => $start_ccode,
 214     };
 215 }
 216
 217 # populate an item list with its title and upc, oclc and isbn normalized.
 218 # Not really intended to be exported.
 219 sub GetShelfInfo {
 220     my @items = @_;
 221     my $marcflavour = C4::Context->preference("marcflavour");
 222     my @valid_items;
 223     for my $item ( @items ) {
 224         my $biblio = Koha::Biblios->find( $item->{biblionumber} );
 225         next unless defined $biblio;
 226
 227         $item->{biblio_object} = $biblio;
 228         $item->{biblionumber}  = $biblio->biblionumber;
 229         $item->{title}         = $biblio->title;
 230         $item->{subtitle}      = $biblio->subtitle;
 231         $item->{medium}        = $biblio->medium;
 232         $item->{part_number}   = $biblio->part_number;
 233         $item->{part_name}     = $biblio->part_name;
 234         my $this_record = GetMarcBiblio({ biblionumber => $biblio->biblionumber });
 235         $item->{'browser_normalized_upc'} = GetNormalizedUPC($this_record,$marcflavour);
 236         $item->{'browser_normalized_oclc'} = GetNormalizedOCLCNumber($this_record,$marcflavour);
 237         $item->{'browser_normalized_isbn'} = GetNormalizedISBN(undef,$this_record,$marcflavour);
 238         $item->{'browser_normalized_ean'} = GetNormalizedEAN($this_record,$marcflavour);
 239         push @valid_items, $item;
 240     }
 241     return @valid_items;
 242 }
 243
 244 1;