#!/usr/bin/perl

# Copyright 2007 LibLime
#
# This file is part of Koha.
#
# Koha is free software; you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version.
#
# Koha is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with Koha; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#

use strict;
use warnings;

use CGI;
use C4::Auth qw/check_api_auth/;
use C4::Context;
use C4::Koha;
use XML::Simple;

my $query = new CGI;

my ($status, $cookie, $sessionID) = check_api_auth($query, { editcatalogue => 'edit_catalogue'} );

if ($status eq "ok") {
    print $query->header(-type => 'text/xml', cookie => $cookie);
} else {
    print $query->header(-type => 'text/xml', -status => '403 Forbidden');
    print XMLout({ auth_status => $status }, NoAttr => 1, RootName => 'response', XMLDecl => 1);
    exit 0;
}

my $dbh = C4::Context->dbh;

# get list of required tags
my $result = {};
$result->{'auth_status'} = $status;
_get_mandatory_tags($result);
_get_mandatory_subfields($result);
_get_reserved_tags($result);
_get_bib_number_tag($result);
_get_biblioitem_itemtypes($result);
print XMLout($result, NoAttr => 1, RootName => 'response', XMLDecl => 1,  
        GroupTags => {mandatory_tags => 'tag', mandatory_subfields => 'subfield', reserved_tags => 'tag',
                      valid_values => 'value'});

exit 0;

sub _get_mandatory_tags {
    my $result = shift;
    my $sth = $dbh->prepare_cached("SELECT tagfield FROM marc_tag_structure WHERE frameworkcode = '' AND mandatory = 1");
    $sth->execute();
    my @tags = ();
    while (my $row = $sth->fetchrow_arrayref) {
        push @tags, $row->[0];
    }
    $result->{'mandatory_tags'} = \@tags;
}

sub _get_mandatory_subfields {
    my $result = shift;
    my $sth = $dbh->prepare_cached("SELECT tagfield, tagsubfield 
                                    FROM marc_subfield_structure 
                                    WHERE frameworkcode = '' 
                                    AND tagsubfield <> '\@' 
                                    AND kohafield <> 'biblioitems.itemtype'
                                    AND mandatory = 1");
    $sth->execute();
    my @subfields = ();
    while (my $row = $sth->fetchrow_arrayref) {
        push @subfields, { tag => $row->[0], subfield_label => $row->[1] };
    }
    $result->{'mandatory_subfields'} = \@subfields;
}

sub _get_reserved_tags {
    my $result = shift;
    my $sth = $dbh->prepare_cached("SELECT DISTINCT tagfield
                                    FROM marc_subfield_structure 
                                    WHERE frameworkcode = '' 
                                    AND (kohafield = 'items.itemnumber' OR kohafield = 'biblioitems.itemtype' OR
                                         kohafield = 'biblio.biblionumber')");
    $sth->execute();
    my @tags = ();
    while (my $row = $sth->fetchrow_arrayref) {
        push @tags, $row->[0];
    }
    $result->{'reserved_tags'} = \@tags;
}

sub _get_bib_number_tag {
    my $result = shift;
    my $sth = $dbh->prepare_cached("SELECT tagfield, tagsubfield
                                    FROM marc_subfield_structure 
                                    WHERE frameworkcode = '' 
                                    AND kohafield = 'biblio.biblionumber'");
    $sth->execute();
    my @tags = ();
    while (my $row = $sth->fetchrow_arrayref) {
        push @tags, { tag => $row->[0], subfield => $row->[1] };
    }
    $result->{'bib_number'} = \@tags;
}

sub _get_biblioitem_itemtypes {
    my $result = shift;
    my $itemtypes = GetItemTypes;
    my $sth = $dbh->prepare_cached("SELECT tagfield, tagsubfield
                                    FROM marc_subfield_structure 
                                    WHERE frameworkcode = '' 
                                    AND kohafield = 'biblioitems.itemtype'");
    $sth->execute();
    my @tags = ();
    while (my $row = $sth->fetchrow_arrayref) {
        push @tags, { tag => $row->[0], subfield => $row->[1] };
    }
    my @valid_values = map { { code => $_,  description => $itemtypes->{$_}->{'description'} } } sort keys %$itemtypes;
    $result->{'special_entry'} = { field => \@tags,  valid_values => \@valid_values };
    
}