#
# $Id: studentcalc.pm,v 1.39 2006/05/01 06:17:16 raeburn Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA 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.
#
# LON-CAPA 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 LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#
# The LearningOnline Network with CAPA
# Spreadsheet/Grades Display Handler
#
# POD required stuff:

=head1 NAME

studentcalc

=head1 SYNOPSIS

=head1 DESCRIPTION

=over 4

=cut

###################################################
###                 StudentSheet                ###
###################################################
package Apache::studentcalc;

use warnings FATAL=>'all';
no warnings 'uninitialized';

use strict;
use Apache::Constants qw(:common :http);
use Apache::lonnet;
use Apache::loncommon();
use Apache::loncoursedata();
use Apache::lonnavmaps;
use Apache::Spreadsheet();
use Apache::assesscalc();
use HTML::Entities();
use Time::HiRes;
use Apache::lonlocal;

@Apache::studentcalc::ISA = ('Apache::Spreadsheet');

my @Sequences = ();
my $navmap;
my %Exportrows = ();

my $current_course;

sub initialize {
    &initialize_sequence_cache();
    &Apache::assesscalc::initialize($navmap);
}

sub initialize_package {
    $current_course = $env{'request.course.id'};
    &initialize_sequence_cache();
    &load_cached_export_rows();
}

sub ensure_correct_sequence_data {
    if ($current_course ne $env{'request.course.id'}) {
        &initialize_sequence_cache();
        $current_course = $env{'request.course.id'};
    }
    return;
}

sub initialize_sequence_cache {
    #
    # Set up the sequences and assessments
    undef(@Sequences);
    undef($navmap);
    $navmap = Apache::lonnavmaps::navmap->new();
    if (!defined($navmap)) {
        &Apache::lonnet::logthis('student spreadsheet:Can not open Coursemap');
    }
    my @all_sequences = $navmap->retrieveResources(undef,
                                               sub { shift->is_map(); },1,0,1);
    for my $sequence ($navmap->getById('0.0'), @all_sequences) {
	if ($navmap->hasResource($sequence,sub { shift->is_problem(); }, 0)){
            push(@Sequences,$sequence);
	    &get_resources($sequence);
        }
    }
}

my %res_memoize;
sub get_resources {
    my ($seq) = @_;
    if (exists($res_memoize{$seq->symb()})) {
	return @{$res_memoize{$seq->symb()}};
    }
    return () if (! defined($navmap) || ! ref($navmap));
    my @resources = $navmap->retrieveResources($seq,
                                               sub { shift->is_problem(); },
                                               0,0,0);
    $res_memoize{$seq->symb()}=\@resources;
    return @resources;
}

sub clear_package {
    undef(@Sequences);
    undef(%Exportrows);
    undef(%res_memoize);
    undef($navmap);
    &Apache::assesscalc::clear_package();
}

sub get_title {
    my $self = shift;
    my @title = ();
    #
    # Determine the students name
    my $name = &Apache::loncommon::plainname($self->{'name'},
					     $self->{'domain'});
    push (@title,$name);
    push (@title,$self->{'coursedesc'});
    push (@title,&Apache::lonlocal::locallocaltime(time));
    return @title;
}

sub get_html_title {
    my $self = shift;
    my ($name,$desc,$time) = $self->get_title();
    my $title = '<h1>'.$name;
    if ($env{'user.name'} ne $self->{'name'} && 
        $env{'user.domain'} ne $self->{'domain'}) {
        $title .= ' '.&Apache::loncommon::aboutmewrapper
                                    ($self->{'name'}.'@'.$self->{'domain'},
                                     $self->{'name'},$self->{'domain'});
    }
    $title .= "</h1>\n";
    $title .= '<h2>'.$desc."</h2>\n";
    $title .= '<h3>'.$time.'</h3>';
    return $title;
}

sub parent_link {
    my $self = shift;
    return '<p><a href="/adm/classcalc">'.&mt('Course level sheet').'</a></p>'."\n";
}

sub convenience_links {
    my $self = shift;
    my ($resource) = @_;
    my $result=&Apache::loncommon::submlink('<img src="/adm/lonMisc/subm_button.gif" border="0" />',$self->{'name'},$self->{'domain'},$resource->symb,'LONcatInfo');
    $result .= &Apache::loncommon::pgrdlink('<img src="/adm/lonMisc/pgrd_button.gif" border="0" />',$self->{'name'},$self->{'domain'},$resource->symb,'LONcatInfo');
    $result .= &Apache::loncommon::pprmlink('<img src="/adm/lonMisc/pprm_button.gif" border="0" />',$self->{'name'},$self->{'domain'},$resource->symb,'LONcatInfo');
    return $result;
}

sub outsheet_html {
    my $self = shift;
    my ($r) = @_;
    my $importcolor = '#FFFFAA';
    my $exportcolor = '#88FF88';
    ####################################
    # Get the list of assessment files #
    ####################################
    my @AssessFileNames = $self->othersheets('assesscalc');
    my $editing_is_allowed = &Apache::lonnet::allowed('mgr',
                                                $env{'request.course.id'});
    ####################################
    # Report any calculation errors    #
    ####################################
    $r->print($self->html_report_error());
    ####################################
    # Determine table structure        #
    ####################################
    my $num_uneditable = 26;
    my $num_left = 52-$num_uneditable;
    my %lt=&Apache::lonlocal::texthash(
				       'st' => 'Student',
				       'im' => 'Import',
				       'ca' => 'Calculations',
				       'as' => 'Assessment',
				       'ro' => 'Row',
				       );
    my $tableheader =<<"END";
<p>
<table border="2">
<tr>
  <th colspan="2" rowspan="2"><font size="+2">$lt{'st'}</font></th>
  <td bgcolor="$importcolor" colspan="$num_uneditable">
      <b><font size="+1">$lt{'im'}</font></b></td>
  <td colspan="$num_left">
      <b><font size="+1">$lt{'ca'}</font></b></td>
</tr><tr>
END
    my $label_num = 0;
    foreach (split(//,'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz')){
        if ($label_num<$num_uneditable) { 
            $tableheader .='<td bgcolor="'.$importcolor.'">';
        } else {
            $tableheader .='<td>';
        }
        $tableheader .="<b><font size=+1>$_</font></b></td>";
        $label_num++;
    }
    $tableheader .="</tr>\n";
    if ($self->blackout()) {
        $r->print('<font color="red" size="+2"><p>'.
                  &mt('Some computations are not available at this time.').'<br />'.
                  &mt('There are problems whose status you are not allowed to view.').
                  '</font></p>'."\n");
    } else {
        $r->print($tableheader);
        #
        # Print out template row
        if (exists($env{'request.role.adv'}) && $env{'request.role.adv'}) {
            $r->print('<tr><td>Template</td><td>&nbsp;</td>'.
                      $self->html_template_row($num_uneditable,
                                               $importcolor)."</tr>\n");
        }
        #
        # Print out summary/export row
        $r->print('<tr><td>'.&mt('Summary').'</td><td>0</td>'.
                  $self->html_export_row($exportcolor)."</tr>\n");
    }
    $r->print("</table>\n");
    #
    # Prepare to output rows
    if (exists($env{'request.role.adv'}) && $env{'request.role.adv'}) {
        $tableheader =<<"END";
</p><p>
<table border="2">
<tr><th>$lt{'ro'}</th><th>&nbsp;</th><th>$lt{'as'}</th>
END
    } else {
        $tableheader =<<"END";
</p><p>
<table border="2">
<tr><th>&nbsp;</th><th>$lt{'as'}</th>
END
    }
    foreach (split(//,'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz')){
	if ($label_num<$num_uneditable) { 
            $tableheader.='<td bgcolor="#FFDDDD">';
        } else {
            $tableheader.='<td>';
        }
        $tableheader.="<b><font size=+1>$_</font></b></td>";
    }
    $tableheader.="\n";
    #
    my $num_output = 1;
    if (scalar(@Sequences)< 1) {
        &initialize_sequence_cache();
    }
    foreach my $Sequence (@Sequences) {
	$r->print("<h3>".$Sequence->compTitle."</h3>\n");

        my @resources = &get_resources($Sequence);
        my $first_rownum =
            $self->get_row_number_from_key($resources[0]->symb);
        my $last_rownum = 
            $self->get_row_number_from_key($resources[-1]->symb);
        $r->print(&assess_file_selector([$first_rownum, $last_rownum],
                                        undef, \@AssessFileNames));

 	$r->print($tableheader);
	foreach my $resource (@resources) {
	    my $rownum = $self->get_row_number_from_key($resource->symb);
            my $assess_filename = $self->{'row_source'}->{$rownum};
            my $row_output = '<tr>';
            if ($editing_is_allowed) {
                $row_output .= '<td>'.$rownum.'</td>';
                $row_output .= '<td>'.$self->convenience_links($resource).'</td>';
                $row_output .= '<td>'.
                    '<a href="/adm/assesscalc?sname='.$self->{'name'}.
                    '&sdomain='.$self->{'domain'}.
                    '&filename='.$assess_filename.
                    '&usymb='.&Apache::lonnet::escape($resource->symb).
                    '">'.$resource->compTitle.'</a><br />';
                $row_output .= &assess_file_selector($rownum,
                                                     $assess_filename,
                                                     \@AssessFileNames).
                                                         '</td>';
            } else {
                $row_output .= '<td><a href="'.$resource->src.'?symb='.
                    &Apache::lonnet::escape($resource->symb).
                    '">Go&nbsp;To</a>';
                $row_output .= '</td><td>'.$resource->compTitle.'</td>';
            }
            if ($self->blackout() && $self->{'blackout_rows'}->{$rownum}>0) {
                $row_output .= 
                    '<td colspan="52">'.&mt('Unavailable at this time').'</td></tr>'."\n";
            } else {
                $row_output .= $self->html_row($num_uneditable,$rownum,
                                               $exportcolor,$importcolor).
                    "</tr>\n";
            }
            $r->print($row_output);
	}
	$r->print("</table>\n");
    }
    $r->print("</p>\n");
    return;
}

########################################################
########################################################

=pod

=item &assess_file_selector()

=cut

########################################################
########################################################
sub assess_file_selector {
    my ($row,$default,$AssessFiles)=@_;
    if (!defined($AssessFiles) || ! @$AssessFiles) {
        return '';
    }
    return '' if (! &Apache::lonnet::allowed('mgr',$env{'request.course.id'}));
    my $element_name;
    my $source_row = $row;
    if (ref($row)) {
        my ($first_rownum, $last_rownum) = @$row;
        $element_name = "FileSelect_${first_rownum}_${last_rownum}";
        $source_row = "${first_rownum}:${last_rownum}";
    } else {
        $element_name = 'FileSelect_'.$row;
    }
    my $load_dialog = '<select size="1" name="'.$element_name.'" '.
        'onchange="'.
        "document.sheet.cell.value='source_${source_row}';".
        "document.sheet.newformula.value=document.sheet.$element_name\.value;".
        'document.sheet.submit()" '.'>'."\n";
    if (ref($row)) {
        $load_dialog .= '    <option name="" value="">' .
            &mt("Select spreadsheet for entire sequence")
            . "</option>\n";
    }
    foreach my $file (@{$AssessFiles}) {
        $load_dialog .= '    <option name="'.$file.'"';
        $load_dialog .= ' selected' if ($default eq $file);
        $load_dialog .= '>'.$file."</option>\n";
    }
    $load_dialog .= "</select>\n";
    return $load_dialog;
}

sub modify_cell {
    my $self = shift;
    my ($cell,$formula) = @_;

    my $set_row = sub {
        my $row = shift;
        my $formula = shift;
        my $cell = 'A' . $row;
        $self->{'row_source'}->{$row} = $formula;
        my $original_source = $self->formula($cell);
        if ($original_source =~ /__&&&__/) {
            ($original_source,undef) = split('__&&&__',$original_source);
        }
        $formula = $original_source.'__&&&__'.$formula;
        $self->set_formula($cell,$formula);
    };

    if ($cell =~ /^source_(\d+):(\d+)$/) {
        my $first_row = $1;
        my $last_row = $2;
        for my $row ($first_row..$last_row) {
            $set_row->($row, $formula);
        }
    } elsif ($cell =~ /^source_(\d+)$/) {
        # Need to make sure $formula is a valid filename....
        my $row = $1;
        $set_row->($row, $formula);
    } elsif ($cell =~ /([A-z])\-/) {
        $cell = 'template_'.$1;
        $self->set_formula($cell,$formula);
    } elsif ($cell !~ /^([A-z](\d+)|template_[A-z])$/) {
        return;
    }
    $self->rebuild_stats();
    return;
}

sub csv_rows {
    # writes the meat of the spreadsheet to an excel worksheet.  Called
    # by Spreadsheet::outsheet_excel;
    my $self = shift;
    my ($connection,$filehandle) = @_;
    #
    # Write a header row
    $self->csv_output_row($filehandle,undef,
                          (&mt('Sequence or Folder'),&mt('Assessment title')));
    #
    # Write each assessments row
    if (scalar(@Sequences)< 1) {
        &initialize_sequence_cache();
    }
    foreach my $Sequence (@Sequences) {
	foreach my $resource (&get_resources($Sequence)) {
	    my $rownum = $self->get_row_number_from_key($resource->symb);
            my @assessdata = ($Sequence->compTitle,
                              $resource->compTitle);
            $self->csv_output_row($filehandle,$rownum,@assessdata);
        }
    }
    return;
}

sub excel_rows {
    # writes the meat of the spreadsheet to an excel worksheet.  Called
    # by Spreadsheet::outsheet_excel;
    my $self = shift;
    my ($connection,$worksheet,$cols_output,$rows_output,$format) = @_;
    #
    # Write a header row
    $cols_output = 0;
    foreach my $value ('Container','Assessment title') {
        $worksheet->write($rows_output,$cols_output++,&mt($value),$format->{'h4'});
    }
    $rows_output++;    
    #
    # Write each assessments row
    if (scalar(@Sequences)< 1) {
        &initialize_sequence_cache();
    }
    foreach my $Sequence (@Sequences) {
	foreach my $resource (&get_resources($Sequence)) {
	    my $rownum = $self->get_row_number_from_key($resource->symb);
            my @assessdata = ($Sequence->compTitle,
                              $resource->compTitle);
            $self->excel_output_row($worksheet,$rownum,$rows_output++,
                                    @assessdata);
        }
    }
    return;
}

sub outsheet_recursive_excel {
    my $self = shift;
    my ($r) = @_;
} 

##
## Routines to deal with sequences in the safe space
##
sub get_rows_in_sequence {
    my $self = shift();
    my ($sequence) = @_;
    my @Rows;
    my @resources = &get_resources($sequence);
    foreach my $resource (@resources) {
        my $rownum = $self->get_row_number_from_key($resource->symb);
        push (@Rows,$rownum);
    }
    return @Rows;
}

sub remove_sequence_data_from_safe_space {
    my $self = shift();
    my $command = 'undef(%Sequence_Rows);';
    $self->{'safe'}->reval($command);
}

sub put_sequence_data_in_safe_space {
    my $self = shift();
    my $data = 'undef(%Sequence_Rows);';
    # Build up the %Sequence_Rows hash - each sequence title is associated with
    # an array pointer, which holds the rows in the sequence.
    foreach my $seq (@Sequences) {
        my @Rows = $self->get_rows_in_sequence($seq);
        # 
        # Potential problems with sequence titles:
        # 1. duplicate titles - they get the total for the titles
        # 2. control characters in titles - use q{} around the string to
        #    deal with it.  
        my $title = &HTML::Entities::decode($seq->title());
        $title =~ s/&\#058;/:/g;
        if (@Rows) {
            $data .= 'push(@{$Sequence_Rows{"'.quotemeta($title).'"}},'.
                '('.join(',',@Rows).'));'."\n";;
        }
    }
    my $new_code = $data.<<'END';
sub SUMSEQ {
    my ($col,@titles) = @_;
    return 'bad column: '.$col if ($col !~ /^[A-z]$/);
    my $sum = 0;
    foreach my $title (@titles) {
        while (my ($seq_title,$rows) = each(%Sequence_Rows)) {
            my $regexp;
            if ($title =~ /^regexp:(.*)$/) {
                $regexp = $1;
            } elsif (lc($title) eq 'all') {
                $regexp = '.';
            }
            if (defined($regexp)) {
                next if ($seq_title !~ /$regexp/);
            } else {
                next if ($seq_title ne $title);
            }
            foreach my $rownum (@{$rows}) {
                my $cell = $col.$rownum;
                if (exists($sheet_values{$cell})) {
                    $sum += $sheet_values{$cell};
                }
            }
        }
    }
    return $sum;
}
END
    $self->{'safe'}->reval($new_code);
    return;
}

##
## Main computation method
##
sub compute {
    my $self = shift;
    my ($r) = @_;
    if (! defined($current_course) ||
        $current_course ne $env{'request.course.id'} ||
        ! @Sequences ) {
        $current_course = $env{'request.course.id'};
        &clear_package();
        &initialize_sequence_cache();
    }
    $self->initialize_safe_space();
    &Apache::assesscalc::initialize_package($self->{'name'},$self->{'domain'},
                                            $navmap);
    my %f = $self->formulas();
    #
    # Process the formulas list - 
    #   the formula for the A column of a row is symb__&&__filename
    my %c = $self->constants();
    foreach my $seq (@Sequences) {
        foreach my $resource (&get_resources($seq)) {
            my $rownum = $self->get_row_number_from_key($resource->symb);
            my $cell = 'A'.$rownum;
            my $assess_filename = 'Default';
            if (exists($self->{'row_source'}->{$rownum})) {
                $assess_filename = $self->{'row_source'}->{$rownum};
            } else {
                $self->{'row_source'}->{$rownum} = $assess_filename;
            }
            $f{$cell} = $resource->symb.'__&&&__'.$assess_filename;
            my $assessSheet;
                $assessSheet = Apache::assesscalc->new($self->{'name'},
                                                       $self->{'domain'},
                                                       $assess_filename,
                                                       $resource->symb,
						       $self->{'section'},
                                                       $self->{'groups'});
            my @exportdata = $assessSheet->export_data($r);
            #
            if ($assessSheet->badcalc()) {
                $self->set_calcerror(
            &mt('Error computing row for assessment "[_1]" (row [_2]):[_3]',
                $assessSheet->get_title(),$rownum,$assessSheet->calcerror()));
            }
            #
            if ($assessSheet->blackout()) {
                $self->blackout(1);
                $self->{'blackout_rows'}->{$rownum} = 1;
            }
            #
            # Be sure not to disturb the formulas in the 'A' column
            my $data = shift(@exportdata);
            $c{$cell} = $data if (defined($data));
            #
            # Deal with the remaining columns
            my $i=0;
            foreach (split(//,'BCDEFGHIJKLMNOPQRSTUVWXYZ')) {
                my $cell = $_.$rownum;
                my $data = shift(@exportdata);
                if (defined($data)) {
                    $f{$cell} = 'import';
                    $c{$cell} = $data;
                }
                $i++;
            }
        }
    }
    $self->constants(\%c);
    $self->formulas(\%f);
    $self->put_sequence_data_in_safe_space();
    $self->calcsheet();
    $self->remove_sequence_data_from_safe_space();
    #
    # Store export row in cache
    my @exportarray=$self->exportrow();
    my $student = $self->{'name'}.':'.$self->{'domain'};
    $Exportrows{$student}->{'time'} = time;
    $Exportrows{$student}->{'data'} = \@exportarray;
    # save export row
    $self->save_export_data();
    #
    $self->save() if ($self->need_to_save());
    return;
}

sub set_row_sources {
    my $self = shift;
    $self->check_formulas_loaded();
    while (my ($cell,$value) = each(%{$self->{'formulas'}})) {
        next if ($cell !~ /^A(\d+)$/ || $1 < 1);
        my $row = $1;
        (undef,$value) = split('__&&&__',$value);
        $value = 'Default' if (! defined($value));
        $self->{'row_source'}->{$row} = $value;
    }
    return;
}

sub set_row_numbers {
    my $self = shift;
    $self->check_formulas_loaded();
    while (my ($cell,$formula) = each(%{$self->{'formulas'}})) {
        next if ($cell !~ /^A(\d+)/);
        my $row = $1;
        next if ($row == 0);
        my ($symb,undef) = split('__&&&__',$formula);
        $self->{'row_numbers'}->{$symb} = $row;
        $self->{'maxrow'} = $row if ($row > $self->{'maxrow'});
    }
}

sub get_row_number_from_symb {
    my $self = shift;
    my ($key) = @_;
    ($key,undef) = split('__&&&__',$key) if ($key =~ /__&&&__/);
    return $self->get_row_number_from_key($key);
}

#############################################
#############################################

=pod

=item &load_cached_export_rows

Retrieves and parsers the export rows of the student spreadsheets.
These rows are saved in the courses directory in the format:

 sname:sdom:studentcalc:.time => time

 sname:sdom:studentcalc => ___=___Adata___;___Bdata___;___Cdata___;___ .....

=cut

#############################################
#############################################
sub load_cached_export_rows {
    undef(%Exportrows);
    my @tmp = &Apache::lonnet::dump('nohist_calculatedsheets',
		     $env{'course.'.$env{'request.course.id'}.'.domain'},
		     $env{'course.'.$env{'request.course.id'}.'.num'},undef);
    my %Selected_Assess_Sheet;
    if ($tmp[0] =~ /^error/) {
        &Apache::lonnet::logthis('unable to read cached student export rows '.
                                 'for course '.$env{'request.course.id'});
        return;
    }
    my %tmp = @tmp;
    while (my ($key,$sheetdata) = each(%tmp)) {
        my ($sname,$sdom,$sheettype,$remainder) = split(':',$key);
        my $student = $sname.':'.$sdom;
        if ($remainder =~ /\.time/) {
            $Exportrows{$student}->{'time'} = $sheetdata;
        } else {
            $sheetdata =~ s/^___=___//;
            my @Data = split('___;___',$sheetdata);
            $Exportrows{$student}->{'data'} = \@Data;
        }
    }
}

#############################################
#############################################

=pod

=item &save_export_data()

Writes the export data for this student to the course cache.

=cut

#############################################
#############################################
sub save_export_data {
    my $self = shift;
    my $student = $self->{'name'}.':'.$self->{'domain'};
    return if ($self->temporary());
    if ($self->badcalc()){
        # do not save data away when calculations have not been done properly.
        delete($Exportrows{$student});
        return;
    }
    return if (! exists($Exportrows{$student}));
    &Apache::assesscalc::save_cached_export_rows($self->{'name'},
                                                 $self->{'domain'});
    return if (! $self->is_default());
    my $key = join(':',($self->{'name'},$self->{'domain'},'studentcalc')).':';
    my $timekey = $key.'.time';
    my $newstore = join('___;___',
                        @{$Exportrows{$student}->{'data'}});
    $newstore = '___=___'.$newstore;
    my $result= &Apache::lonnet::put('nohist_calculatedsheets',
                         { $key     => $newstore,
                           $timekey => $Exportrows{$student}->{'time'} },
                         $self->{'cdom'},
                         $self->{'cnum'});
    return;
}

#############################################
#############################################

=pod

=item &export_data()

Returns the export data associated with the spreadsheet.  Computes the
spreadsheet only if necessary.

=cut

#############################################
#############################################
sub export_data {
    my $self = shift;
    my ($r) = @_;
    my $connection = $r->connection();
    my $student = $self->{'name'}.':'.$self->{'domain'};
    if (! exists($Exportrows{$student}) ||
        ! defined($Exportrows{$student}) ||
        ! exists($Exportrows{$student}->{'data'}) ||
        ! defined($Exportrows{$student}->{'data'}) ||
        ! exists($Exportrows{$student}->{'time'}) ||
        ! defined($Exportrows{$student}->{'time'}) ||
        ! $self->check_expiration_time($Exportrows{$student}->{'time'})) {
        $self->compute($r);
    }
    if ($connection->aborted()) { $self->cleanup(); return; }
    my @Data;
    if ($self->badcalc()) {
        @Data = ();
    } else {
        @Data = @{$Exportrows{$student}->{'data'}};
        for (my $i=0; $i<=$#Data;$i++) {
            if ($Data[$i]=~/\D/ && defined($Data[$i])) {
                $Data[$i]="'".$Data[$i]."'";
            }
        }
    }
    return @Data;
}

1;

__END__