package Catalog;
# modules/Catalog.pm
# Fetch items from the catalog and display them.
use strict;
use Carp;
use DBI;
use CGI qw(:standard);
# create new catalog object
sub new {
my $class = shift;
my $db = shift || croak "Please provide a DBI handle";
return bless {'db' => $db},$class;
}
# return database handle (used internally)
sub db { return $_[0]->{'db'}; }
# Return list of catalog numbers. In an array context, returns
# list of catalog numbers only. In scalar context, returns a hash
# ref in which the keys are catalog numbers, and values are the
# brief descriptions ('names') of the items.
sub list {
my $self = shift;
my $db = $self->db || croak ('No database handle');
my $sth = $db->prepare('SELECT catalog,name FROM ProductList')
|| croak("Prepare:",$db->errstr);
$sth->execute || return;
my %items;
while (my($catalog,$name) = $sth->fetchrow_array) {
$items{$catalog} = $name;
}
return keys %items if wantarray;
return \%items;
}
# Get the information for an entry in the catalog.
# If successful, returns a hashref in which the keys are the column names.
# Returns the length of the image in a key named 'image'. This can be used
# to determine if there is an image to display.
sub info {
my $self = shift;
my $catno = shift || croak ("Provide a catalog number");
my $db = $self->db || croak ('No database handle');
my $sth = $db->prepare(<<END);
SELECT name,ProductList.catalog,price,description,length(image) as image
FROM ProductList
WHERE catalog=?
END
$sth->execute($catno);
my $info = $sth->fetchrow_hashref;
$sth->finish;
return $info;
}
# Return the image data for an entry in the catalog.
sub image {
my $self = shift;
my $catno = shift || croak ("Provide a catalog number");
my $db = $self->db || croak ('No database handle');
my $sth = $db->prepare('SELECT image FROM ProductList WHERE catalog=?');
$sth->execute($catno) || return;
my ($image) = $sth->fetchrow_array;
$sth->finish;
return $image;
}
1;
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