--- loncom/interface/Attic/lonspreadsheet.pm	2001/01/20 12:29:37	1.35
+++ loncom/interface/Attic/lonspreadsheet.pm	2003/02/13 19:07:46	1.168
@@ -1,31 +1,493 @@
+#
+# $Id: lonspreadsheet.pm,v 1.168 2003/02/13 19:07:46 matthew 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
 #
-# 11/11,11/15,11/27,12/04,12/05,12/06,12/07,
-# 12/08,12/09,12/11,12/12,12/15,12/16,12/18,12/19,12/30,
-# 01/01/01,02/01,03/01,19/01,20/01 Gerd Kortemeyer
+# POD required stuff:
+
+=head1 NAME
+
+lonspreadsheet
+
+=head1 SYNOPSIS
+
+Spreadsheet interface to internal LON-CAPA data
+
+=head1 DESCRIPTION
+
+Lonspreadsheet provides course coordinators the ability to manage their
+students grades online.  The students are able to view their own grades, but
+not the grades of their peers.  The spreadsheet is highly customizable,
+offering the ability to use Perl code to manipulate data, as well as many
+built-in functions.
+
+=head2 Functions available to user of lonspreadsheet
+
+=over 4
+
+=cut
+
 
 package Apache::lonspreadsheet;
+            
+use strict;
+use Apache::Constants qw(:common :http);
+use Apache::lonnet;
+use Apache::lonhtmlcommon;
+use HTML::Entities();
+
+# --------------------------------------------------------- Various form fields
+
+sub textfield {
+    my ($title,$name,$value)=@_;
+    return "\n<p><b>$title:</b><br>".
+        '<input type=text name="'.$name.'" size=80 value="'.$value.'">';
+}
+
+sub hiddenfield {
+    my ($name,$value)=@_;
+    return "\n".'<input type=hidden name="'.$name.'" value="'.$value.'">';
+}
+
+sub selectbox {
+    my ($title,$name,$value,%options)=@_;
+    my $selout="\n<p><b>$title:</b><br>".'<select name="'.$name.'">';
+    foreach (sort keys(%options)) {
+        $selout.='<option value="'.$_.'"';
+        if ($_ eq $value) { $selout.=' selected'; }
+        $selout.='>'.$options{$_}.'</option>';
+    }
+    return $selout.'</select>';
+}
+
+my %oldsheets;
+my %loadedcaches;
+
+# ================================================================ Main handler
+#
+# Interactive call to screen
+#
+#
+sub handler {
+    my $r=shift;
+
+    my ($sheettype) = ($r->uri=~/\/(\w+)$/);
+
+    if (! exists($ENV{'form.Status'})) {
+        $ENV{'form.Status'} = 'Active';
+    }
+    if ( ! exists($ENV{'form.output'}) || 
+             ($sheettype ne 'classcalc' && 
+              lc($ENV{'form.output'}) eq 'recursive excel')) {
+        $ENV{'form.output'} = 'HTML';
+    }
+    #
+    # Overload checking
+    #
+    # Check this server
+    my $loaderror=&Apache::lonnet::overloaderror($r);
+    if ($loaderror) { return $loaderror; }
+    # Check the course homeserver
+    $loaderror= &Apache::lonnet::overloaderror($r,
+                      $ENV{'course.'.$ENV{'request.course.id'}.'.home'});
+    if ($loaderror) { return $loaderror; } 
+    #
+    # HTML Header
+    #
+    if ($r->header_only) {
+        $r->content_type('text/html');
+        $r->send_http_header;
+        return OK;
+    }
+    #
+    # Roles Checking
+    #
+    # Needs to be in a course
+    if (! $ENV{'request.course.fn'}) { 
+        # Not in a course, or not allowed to modify parms
+        $ENV{'user.error.msg'}=
+            $r->uri.":opa:0:0:Cannot modify spreadsheet";
+        return HTTP_NOT_ACCEPTABLE; 
+    }
+    #
+    # Get query string for limited number of parameters
+    #
+    &Apache::loncommon::get_unprocessed_cgi
+        ($ENV{'QUERY_STRING'},['uname','udom','usymb','ufn','mapid','resid']);
+    #
+    # Deal with restricted student permissions 
+    #
+    if ($ENV{'request.role'} =~ /^st\./) {
+        delete $ENV{'form.unewfield'}   if (exists($ENV{'form.unewfield'}));
+        delete $ENV{'form.unewformula'} if (exists($ENV{'form.unewformula'}));
+    }
+    #
+    # Look for special assessment spreadsheets - '_feedback', etc.
+    #
+    if (($ENV{'form.usymb'}=~/^\_(\w+)/) && (!$ENV{'form.ufn'} || 
+                                             $ENV{'form.ufn'} eq '' || 
+                                             $ENV{'form.ufn'} eq 'default')) {
+        $ENV{'form.ufn'}='default_'.$1;
+    }
+    if (!$ENV{'form.ufn'} || $ENV{'form.ufn'} eq 'default') {
+        $ENV{'form.ufn'}='course_default_'.$sheettype;
+    }
+    #
+    # Interactive loading of specific sheet?
+    #
+    if (($ENV{'form.load'}) && ($ENV{'form.loadthissheet'} ne 'Default')) {
+        $ENV{'form.ufn'}=$ENV{'form.loadthissheet'};
+    }
+    #
+    # Determine the user name and domain for the sheet.
+    my $aname;
+    my $adom;
+    unless ($ENV{'form.uname'}) {
+        $aname=$ENV{'user.name'};
+        $adom=$ENV{'user.domain'};
+    } else {
+        $aname=$ENV{'form.uname'};
+        $adom=$ENV{'form.udom'};
+    }
+    #
+    # Open page, try to prevent browser cache.
+    #
+    $r->content_type('text/html');
+    $r->header_out('Cache-control','no-cache');
+    $r->header_out('Pragma','no-cache');
+    $r->send_http_header;
+    #
+    # Header....
+    #
+    $r->print('<html><head><title>LON-CAPA Spreadsheet</title>');
+    my $nothing = "''";
+    if ($ENV{'browser.type'} eq 'explorer') {
+        $nothing = "'javascript:void(0);'";
+    }
+
+    if ($ENV{'request.role'} !~ /^st\./) {
+        $r->print(<<ENDSCRIPT);
+<script language="JavaScript">
+
+    var editwin;
+
+    function celledit(cellname,cellformula) {
+        var edit_text = '';
+        // cellformula may contain less-than and greater-than symbols, so
+        // we need to escape them?  
+        edit_text +='<html><head><title>Cell Edit Window</title></head><body>';
+        edit_text += '<form name="editwinform">';
+        edit_text += '<center><h3>Cell '+cellname+'</h3>';
+        edit_text += '<textarea name="newformula" cols="40" rows="6"';
+        edit_text += ' wrap="off" >'+cellformula+'</textarea>';
+        edit_text += '</br>';
+        edit_text += '<input type="button" name="accept" value="Accept"';
+        edit_text += ' onClick=\\\'javascript:';
+        edit_text += 'opener.document.sheet.unewfield.value=';
+        edit_text +=     '"'+cellname+'";';
+        edit_text += 'opener.document.sheet.unewformula.value=';
+        edit_text +=     'document.editwinform.newformula.value;';
+        edit_text += 'opener.document.sheet.submit();';
+        edit_text += 'self.close()\\\' />';
+        edit_text += '&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;';
+        edit_text += '<input type="button" name="abort" ';
+        edit_text +=     'value="Discard Changes"';
+        edit_text += ' onClick="javascript:self.close()" />';
+        edit_text += '</center></body></html>';
+
+        if (editwin != null && !(editwin.closed) ) {
+            editwin.close();
+        }
+
+        editwin = window.open($nothing,'CellEditWin','height=200,width=350,scrollbars=no,resizeable=yes,alwaysRaised=yes,dependent=yes',true);
+        editwin.document.write(edit_text);
+    }
+
+    function changesheet(cn) {
+	document.sheet.unewfield.value=cn;
+        document.sheet.unewformula.value='changesheet';
+        document.sheet.submit();
+    }
+
+    function insertrow(cn) {
+	document.sheet.unewfield.value='insertrow';
+        document.sheet.unewformula.value=cn;
+        document.sheet.submit();
+    }
+
+</script>
+ENDSCRIPT
+    }
+    $r->print('</head>'.&Apache::loncommon::bodytag('Grades Spreadsheet').
+              '<form action="'.$r->uri.'" name="sheet" method="post">');
+    $r->print(&hiddenfield('uname',$ENV{'form.uname'}).
+              &hiddenfield('udom',$ENV{'form.udom'}).
+              &hiddenfield('usymb',$ENV{'form.usymb'}).
+              &hiddenfield('unewfield','').
+              &hiddenfield('unewformula',''));
+    $r->rflush();
+    #
+    # Full recalc?
+    #
+    # Read new sheet or modified worksheet
+    my $sheet=Apache::lonspreadsheet::Spreadsheet->new($aname,$adom,$sheettype,$ENV{'form.usymb'});
+    if ($ENV{'form.forcerecalc'}) {
+        $r->print('<h4>Completely Recalculating Sheet ...</h4>');
+        $sheet->complete_recalc();
+    }
+    #
+    # Global directory configs
+    #
+    $sheet->includedir($r->dir_config('lonIncludes'));
+    $sheet->tmpdir($r->dir_config('lonDaemons').'/tmp/');
+    #
+    # Check user permissions
+    if (($sheet->{'type'}  eq 'classcalc'       ) || 
+        ($sheet->{'uname'} ne $ENV{'user.name'} ) ||
+        ($sheet->{'udom'}  ne $ENV{'user.domain'})) {
+        unless (&Apache::lonnet::allowed('vgr',$sheet->{'cid'})) {
+            $r->print('<h1>Access Permission Denied</h1>'.
+                      '</form></body></html>');
+            return OK;
+        }
+    }
+    # Print out user information
+    $r->print('<h2>'.$sheet->{'coursedesc'}.'</h2>');
+    if ($sheet->{'type'} ne 'classcalc') {
+        $r->print('<h2>'.$sheet->gettitle().'</h2><p>');
+    }
+    if ($sheet->{'type'} eq 'assesscalc') {
+        $r->print('<b>User:</b> '.$sheet->{'uname'}.
+                  '<br /><b>Domain:</b> '.$sheet->{'udom'}.'<br />');
+    }
+    if ($sheet->{'type'} eq 'studentcalc' || 
+        $sheet->{'type'} eq 'assesscalc') {
+        $r->print('<b>Section/Group:</b>'.$sheet->{'csec'}.'</p>');
+    } 
+    #
+    # If a new formula had been entered, go from work copy
+    if ($ENV{'form.unewfield'}) {
+        $r->print('<h2>Modified Workcopy</h2>');
+        #$ENV{'form.unewformula'}=~s/\'/\"/g;
+        $r->print('<p>Cell '.$ENV{'form.unewfield'}.' = <pre>');
+        $r->print(&HTML::Entities::encode($ENV{'form.unewformula'}).
+                  '</pre></p>');
+        $sheet->{'filename'} = $ENV{'form.ufn'};
+        $sheet->tmpread($ENV{'form.unewfield'},$ENV{'form.unewformula'});
+    } elsif ($ENV{'form.saveas'}) {
+        $sheet->{'filename'} = $ENV{'form.ufn'};
+        $sheet->tmpread();
+    } else {
+        $sheet->readsheet($ENV{'form.ufn'});
+    }
+    # Additional options
+    if ($sheet->{'type'} eq 'assesscalc') {
+        $r->print('<p><font size=+2>'.
+                  '<a href="/adm/studentcalc?'.
+                  'uname='.$sheet->{'uname'}.
+                  '&udom='.$sheet->{'udom'}.'">'.
+                  'Level up: Student Sheet</a></font></p>');
+    }
+    if (($sheet->{'type'} eq 'studentcalc') && 
+        (&Apache::lonnet::allowed('vgr',$sheet->{'cid'}))) {
+        $r->print ('<p><font size=+2><a href="/adm/classcalc">'.
+                   'Level up: Course Sheet</a></font></p>');
+    }
+    # Recalc button
+    $r->print('<br />'.
+              '<input type="submit" name="forcerecalc" '.
+              'value="Completely Recalculate Sheet"></p>');
+    # Save dialog
+    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
+        my $fname=$ENV{'form.ufn'};
+        $fname=~s/\_[^\_]+$//;
+        if ($fname eq 'default') { $fname='course_default'; }
+        $r->print('<input type=submit name=saveas value="Save as ...">'.
+                  '<input type=text size=20 name=newfn value="'.$fname.'">'.
+                  'make default: <input type=checkbox name="makedefufn"><p>');
+    }
+    $r->print(&hiddenfield('ufn',$sheet->{'filename'}));
+    # Load dialog
+    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
+        $r->print('<p><input type=submit name=load value="Load ...">'.
+                  '<select name="loadthissheet">'.
+                  '<option name="default">Default</option>');
+        foreach ($sheet->othersheets()) {
+            $r->print('<option name="'.$_.'"');
+            if ($ENV{'form.ufn'} eq $_) {
+                $r->print(' selected');
+            }
+            $r->print('>'.$_.'</option>');
+        } 
+        $r->print('</select><p>');
+        if ($sheet->{'type'} eq 'studentcalc') {
+            $sheet->setothersheets($sheet->othersheets('assesscalc'));
+        }
+    }
+    #
+    # Set up caching mechanisms
+    #
+    &Apache::lonspreadsheet::Spreadsheet::load_spreadsheet_expirationdates();
+    # Clear out old caches if we have not seen this class before.
+    if (exists($oldsheets{'course'}) &&
+        $oldsheets{'course'} ne $sheet->{'cid'}) {
+        undef %oldsheets;
+        undef %loadedcaches;
+    }
+    $oldsheets{'course'} = $sheet->{'cid'};
+    #
+    if ($sheet->{'type'} eq 'classcalc') {
+        $r->print("Loading previously calculated student sheets ...\n");
+        $r->rflush();
+        &Apache::lonspreadsheet::Spreadsheet::cachedcsheets();
+    } elsif ($sheet->{'type'} eq 'studentcalc') {
+        $r->print("Loading previously calculated assessment sheets ...\n");
+        $r->rflush();
+        $sheet->cachedssheets();
+    }
+    # Update sheet, load rows
+    $r->print("Loaded sheet(s), updating rows ...<br>\n");
+    $r->rflush();
+    #
+    $sheet->updatesheet();
+    $r->print("Updated rows, loading row data ...\n");
+    $r->rflush();
+    #
+    $sheet->loadrows($r);
+    $r->print("Loaded row data, calculating sheet ...<br>\n");
+    $r->rflush();
+    #
+    my $calcoutput=$sheet->calcsheet();
+    $r->print('<h3><font color=red>'.$calcoutput.'</h3></font>');
+    # See if something to save
+    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
+        my $fname='';
+        if ($ENV{'form.saveas'} && ($fname=$ENV{'form.newfn'})) {
+            $fname=~s/\W/\_/g;
+            if ($fname eq 'default') { $fname='course_default'; }
+            $fname.='_'.$sheet->{'type'};
+            $sheet->{'filename'} = $fname;
+            $ENV{'form.ufn'}=$fname;
+            $r->print('<p>Saving spreadsheet: '.
+                      $sheet->writesheet($ENV{'form.makedefufn'}).
+                      '<p>');
+        }
+    }
+    #
+    # Write the modified worksheet
+    $r->print('<b>Current sheet:</b> '.$sheet->{'filename'}.'</p>');
+    $sheet->tmpwrite();
+    if ($sheet->{'type'} eq 'assesscalc') {
+        $r->print('<p>Show rows with empty A column: ');
+    } else {
+        $r->print('<p>Show empty rows: ');
+    }
+    #
+    $r->print(&hiddenfield('userselhidden','true').
+              '<input type="checkbox" name="showall" onClick="submit()"');
+    #
+    if ($ENV{'form.showall'}) { 
+        $r->print(' checked'); 
+    } else {
+        unless ($ENV{'form.userselhidden'}) {
+            unless 
+                ($ENV{'course.'.$sheet->{'cid'}.'.hideemptyrows'} eq 'yes') {
+                    $r->print(' checked');
+                    $ENV{'form.showall'}=1;
+                }
+        }
+    }
+    $r->print('>');
+    #
+    # output format select box 
+    $r->print(' Output as <select name="output" size="1" onChange="submit()">'.
+              "\n");
+    foreach my $mode (qw/HTML CSV Excel/) {
+        $r->print('<option value="'.$mode.'"');
+        if ($ENV{'form.output'} eq $mode) {
+            $r->print(' selected ');
+        } 
+        $r->print('>'.$mode.'</option>'."\n");
+    }
+#
+#    Mulit-sheet excel takes too long and does not work at all for large
+#    classes.  Future inclusion of this option may be possible with the
+#    Spreadsheet::WriteExcel::Big and speed improvements.
+#
+#    if ($sheet->{'type'} eq 'classcalc') {
+#        $r->print('<option value="recursive excel"');
+#        if ($ENV{'form.output'} eq 'recursive excel') {
+#            $r->print(' selected ');
+#        } 
+#        $r->print(">Multi-Sheet Excel</option>\n");
+#    }
+    $r->print("</select>\n");
+    #
+    if ($sheet->{'type'} eq 'classcalc') {
+        $r->print('&nbsp;Student Status: '.
+                  &Apache::lonhtmlcommon::StatusOptions
+                  ($ENV{'form.Status'},'sheet'));
+    }
+    #
+    # Buttons to insert rows
+#    $r->print(<<ENDINSERTBUTTONS);
+#<br>
+#<input type='button' onClick='insertrow("top");' 
+#value='Insert Row Top'>
+#<input type='button' onClick='insertrow("bottom");' 
+#value='Insert Row Bottom'><br>
+#ENDINSERTBUTTONS
+    # Print out sheet
+    $sheet->outsheet($r);
+    $r->print('</form></body></html>');
+    #  Done
+    return OK;
+}
 
+1;
+
+#############################################################
+#############################################################
+#############################################################
+
+package Apache::lonspreadsheet::Spreadsheet;
+            
 use strict;
+use Apache::Constants qw(:common :http);
+use Apache::lonnet;
+use Apache::loncoursedata;
+use Apache::File();
 use Safe;
 use Safe::Hole;
 use Opcode;
-use Apache::lonnet;
-use Apache::Constants qw(:common :http);
 use GDBM_File;
+use HTML::Entities();
 use HTML::TokeParser;
-
-#
-# These cache hashes need to be independent of user, resource and course
-# (user and course can/should be in the keys)
-#
-
-my %spreadsheets;
-my %courserdatas;
-my %userrdatas;
-my %defaultsheets;
-my %updatedata;
+use Spreadsheet::WriteExcel;
+use Time::HiRes;
 
 #
 # These global hashes are dependent on user, course and resource, 
@@ -35,78 +497,317 @@ my %courseopt;
 my %useropt;
 my %parmhash;
 
-# Stuff that only the screen handler can know
+#
+# Caches for coursewide information 
+#
+my %Section;
+
+#
+# Caches for previously calculated spreadsheets
+#
+my %expiredates;
+
+#
+# Cache for stores of an individual user
+#
+my $cachedassess;
+my %cachedstores;
+
+#
+# Some hashes for stats on timing and performance
+#
+my %starttimes;
+my %usedtimes;
+my %numbertimes;
 
+#
+# Directories
+#
 my $includedir;
 my $tmpdir;
 
-# =============================================================================
-# ===================================== Implements an instance of a spreadsheet
+sub includedir {
+    my $self = shift;
+    $includedir = shift;
+}
 
-sub initsheet {
-    my $safeeval = new Safe;
-    my $safehole = new Safe::Hole;
-    $safeeval->permit("entereval");
-    $safeeval->permit(":base_math");
-    $safeeval->permit("sort");
-    $safeeval->deny(":base_io");
-    $safehole->wrap(\&Apache::lonnet::EXT,$safeeval,'&EXT');
-    my $code=<<'ENDDEFS';
-# ---------------------------------------------------- Inside of the safe space
+sub tmpdir {
+    my $self = shift;
+    $tmpdir = shift;
+}
+
+my %spreadsheets;
+#my %loadedcaches;
+my %courserdatas;
+my %userrdatas;
+my %defaultsheets;
+my %rowlabel_cache;
+#my %oldsheets;
+
+sub complete_recalc {
+    my $self = shift;
+    undef %spreadsheets;
+    undef %courserdatas;
+    undef %userrdatas;
+    undef %defaultsheets;
+    undef %rowlabel_cache;
+}
+
+sub get_sheet {
+    my $self = shift;
+    my $sheet_id = shift;
+    my $formulas;
+    # if we already have the file loaded and parsed, return the formulas
+    if (exists($self->{'sheets'}->{$sheet_id})) {
+        $formulas = $self->{'sheets'}->{$sheet_id};
+        $self->debug('retrieved '.$sheet_id);
+    } else {
+        # load the file
+        #     set $error and return undef if there is an error loading
+        # parse it
+        #     set $error and return undef if there is an error parsing
+    }
+    return $formulas;
+}
 
 #
-# f: formulas
-# t: intermediate format (variable references expanded)
-# v: output values
-# c: preloaded constants (A-column)
-# rl: row label
+# Load previously cached student spreadsheets for this course
+#
+sub load_spreadsheet_expirationdates {
+    undef %expiredates;
+    my $cid=$ENV{'request.course.id'};
+    my @tmp = &Apache::lonnet::dump('nohist_expirationdates',
+                                    $ENV{'course.'.$cid.'.domain'},
+                                    $ENV{'course.'.$cid.'.num'});
+    if (lc($tmp[0]) !~ /^error/){
+        %expiredates = @tmp;
+    }
+}
 
-%v=(); 
-%t=();
-%f=();
-%c=();
-%rl=();
+# ===================================================== Calculated sheets cache
+#
+# Load previously cached student spreadsheets for this course
+#
+sub cachedcsheets {
+    my $cid=$ENV{'request.course.id'};
+    my @tmp = &Apache::lonnet::dump('nohist_calculatedsheets',
+                                    $ENV{'course.'.$cid.'.domain'},
+                                    $ENV{'course.'.$cid.'.num'});
+    if ($tmp[0] !~ /^error/) {
+        my %StupidTempHash = @tmp;
+        while (my ($key,$value) = each %StupidTempHash) {
+            $Apache::lonspreadsheet::oldsheets{$key} = $value;
+        }
+    }
+}
 
-$maxrow=0;
-$sheettype='';
+#
+# Load previously cached assessment spreadsheets for this student
+#
+sub cachedssheets {
+    my $self = shift;
+    my ($uname,$udom) = @_;
+    $uname = $uname || $self->{'uname'};
+    $udom  = $udom  || $self->{'udom'};
+    if (! exists($Apache::lonspreadsheet::loadedcaches{$uname.'_'.$udom})) {
+        my @tmp = &Apache::lonnet::dump('nohist_calculatedsheets_'.
+                                        $ENV{'request.course.id'},
+                                        $self->{'udom'},
+                                        $self->{'uname'});
+        if ($tmp[0] !~ /^error/) {
+            my %TempHash = @tmp;
+            my $count = 0;
+            while (my ($key,$value) = each %TempHash) {
+                $Apache::lonspreadsheet::oldsheets{$key} = $value;
+                $count++;
+            }
+            $Apache::lonspreadsheet::loadedcaches{$self->{'uname'}.'_'.$self->{'udom'}}=1;
+        }
+    }    
+}
 
-# filename/reference of the sheet
+# ======================================================= Forced recalculation?
+sub checkthis {
+    my ($keyname,$time)=@_;
+    if (! exists($expiredates{$keyname})) {
+        return 0;
+    } else {
+        return ($time<$expiredates{$keyname});
+    }
+}
 
-$filename='';
+sub forcedrecalc {
+    my ($uname,$udom,$stype,$usymb)=@_;
+    my $key=$uname.':'.$udom.':'.$stype.':'.$usymb;
+    my $time=$Apache::lonspreadsheet::oldsheets{$key.'.time'};
+    if ($ENV{'form.forcerecalc'}) { return 1; }
+    unless ($time) { return 1; }
+    if ($stype eq 'assesscalc') {
+        my $map=(split(/___/,$usymb))[0];
+        if (&checkthis('::assesscalc:',$time) ||
+            &checkthis('::assesscalc:'.$map,$time) ||
+            &checkthis('::assesscalc:'.$usymb,$time) ||
+            &checkthis($uname.':'.$udom.':assesscalc:',$time) ||
+            &checkthis($uname.':'.$udom.':assesscalc:'.$map,$time) ||
+            &checkthis($uname.':'.$udom.':assesscalc:'.$usymb,$time)) {
+            return 1;
+        }
+    } else {
+        if (&checkthis('::studentcalc:',$time) || 
+            &checkthis($uname.':'.$udom.':studentcalc:',$time)) {
+	    return 1;
+        }
+    }
+    return 0; 
+}
 
-# user data
-$uname='';
-$uhome='';
-$udom='';
 
-# course data
+##################################################
+##################################################
 
-$csec='';
-$chome='';
-$cnum='';
-$cdom='';
-$cid='';
-$cfn='';
+=pod
 
-# symb
+=item &parmval()
+
+Determine the value of a parameter.
+
+Inputs: $what, the parameter needed, $symb, $uname, $udom, $csec 
+
+Returns: The value of a parameter, or '' if none.
+
+This function cascades through the possible levels searching for a value for
+a parameter.  The levels are checked in the following order:
+user, course (at section level and course level), map, and lonnet::metadata.
+This function uses %parmhash, which must be tied prior to calling it.
+This function also requires %courseopt and %useropt to be initialized for
+this user and course.
+
+=cut
+
+##################################################
+##################################################
+sub parmval {
+    my ($what,$symb,$uname,$udom,$csec)=@_;
+    return '' if (!$symb);
+    #
+    my $cid   = $ENV{'request.course.id'};
+    my $result='';
+    #
+    my ($mapname,$id,$fn)=split(/\_\_\_/,$symb);
+    # Cascading lookup scheme
+    my $rwhat=$what;
+    $what =~ s/^parameter\_//;
+    $what =~ s/\_([^\_]+)$/\.$1/;
+    #
+    my $symbparm = $symb.'.'.$what;
+    my $mapparm  = $mapname.'___(all).'.$what;
+    my $usercourseprefix = $uname.'_'.$udom.'_'.$cid;
+    #
+    my $seclevel  = $usercourseprefix.'.['.$csec.'].'.$what;
+    my $seclevelr = $usercourseprefix.'.['.$csec.'].'.$symbparm;
+    my $seclevelm = $usercourseprefix.'.['.$csec.'].'.$mapparm;
+    #
+    my $courselevel  = $usercourseprefix.'.'.$what;
+    my $courselevelr = $usercourseprefix.'.'.$symbparm;
+    my $courselevelm = $usercourseprefix.'.'.$mapparm;
+    # fourth, check user
+    if (defined($uname)) {
+        return $useropt{$courselevelr} if (defined($useropt{$courselevelr}));
+        return $useropt{$courselevelm} if (defined($useropt{$courselevelm}));
+        return $useropt{$courselevel}  if (defined($useropt{$courselevel}));
+    }
+    # third, check course
+    if (defined($csec)) {
+        return $courseopt{$seclevelr} if (defined($courseopt{$seclevelr}));
+        return $courseopt{$seclevelm} if (defined($courseopt{$seclevelm}));
+        return $courseopt{$seclevel}  if (defined($courseopt{$seclevel}));
+    }
+    #
+    return $courseopt{$courselevelr} if (defined($courseopt{$courselevelr}));
+    return $courseopt{$courselevelm} if (defined($courseopt{$courselevelm}));
+    return $courseopt{$courselevel}  if (defined($courseopt{$courselevel}));
+    # second, check map parms
+    my $thisparm = $parmhash{$symbparm};
+    return $thisparm if (defined($thisparm));
+    # first, check default
+    return &Apache::lonnet::metadata($fn,$rwhat.'.default');
+}
+
+#
+# new: Make a new spreadsheet
+#
+sub new {
+    my $this = shift;
+    my $class = ref($this) || $this;
+    #
+    my ($uname,$udom,$stype,$usymb)=@_;
+    #
+    my $self = {
+        uname => $uname,
+        udom  => $udom,
+        type  => $stype,
+        usymb => $usymb,
+        errorlog => '',
+        maxrow   => '',
+        mapid => $ENV{'form.mapid'},
+        resid => $ENV{'form.resid'},
+        cid   => $ENV{'request.course.id'},
+        csec  => $Section{$uname.':'.$udom},
+        cnum  => $ENV{'course.'.$ENV{'request.course.id'}.'.num'},
+        cdom  => $ENV{'course.'.$ENV{'request.course.id'}.'.domain'},
+        chome => $ENV{'course.'.$ENV{'request.course.id'}.'.home'},
+        coursefilename => $ENV{'request.course.fn'},
+        coursedesc => $ENV{'course.'.$ENV{'request.course.id'}.'.description'},
+        rows       => [],
+        template_cells => [],
+        };
+    $self->{'uhome'} = &Apache::lonnet::homeserver($uname,$udom);
+    #
+    #
+    $self->{'formulas'} = {};
+    $self->{'constants'} = {};
+    $self->{'othersheets'} = [];
+    $self->{'rowlabel'} = {};
+    #
+    #
+    $self->{'safe'} = &initsheet($self->{'type'});
+    $self->{'root'} = $self->{'safe'}->root();
+    #
+    # Place some of the %$self  items into the safe space except the safe space
+    # itself
+    my $initstring = '';
+    foreach (qw/uname udom type usymb cid csec coursefilename
+             cnum cdom chome uhome/) {
+        $initstring.= qq{\$$_="$self->{$_}";};
+    }
+    $self->{'safe'}->reval($initstring);
+    bless($self,$class);
+    return $self;
+}
+
+##
+## mask - used to reside in the safe space.  
+##
+{
 
-$usymb='';
+my %memoizer;
 
 sub mask {
     my ($lower,$upper)=@_;
-
-    $lower=~/([A-Za-z]|\*)(\d+|\*)/;
-    my $la=$1;
-    my $ld=$2;
-
-    $upper=~/([A-Za-z]|\*)(\d+|\*)/;
-    my $ua=$1;
-    my $ud=$2;
+    my $key = $lower.'_'.$upper;
+    if (exists($memoizer{$key})) {
+        return $memoizer{$key};
+    }
+    $upper = $lower if (! defined($upper));
+    #
+    my ($la,$ld) = ($lower=~/([A-Za-z]|\*)(\d+|\*)/);
+    my ($ua,$ud) = ($upper=~/([A-Za-z]|\*)(\d+|\*)/);
+    #
     my $alpha='';
     my $num='';
-
+    #
     if (($la eq '*') || ($ua eq '*')) {
-       $alpha='[A-Za-z]';
+        $alpha='[A-Za-z]';
     } else {
        if (($la=~/[A-Z]/) && ($ua=~/[A-Z]/) ||
            ($la=~/[a-z]/) && ($ua=~/[a-z]/)) {
@@ -115,27 +816,28 @@ sub mask {
           $alpha='['.$la.'-Za-'.$ua.']';
        }
     }   
-
     if (($ld eq '*') || ($ud eq '*')) {
 	$num='\d+';
     } else {
         if (length($ld)!=length($ud)) {
            $num.='(';
-	   map {
+	   foreach ($ld=~m/\d/g) {
               $num.='['.$_.'-9]';
-           } ($ld=~m/\d/g);
+	   }
            if (length($ud)-length($ld)>1) {
               $num.='|\d{'.(length($ld)+1).','.(length($ud)-1).'}';
 	   }
            $num.='|';
-           map {
+           foreach ($ud=~m/\d/g) {
                $num.='[0-'.$_.']';
-           } ($ud=~m/\d/g);
+           }
            $num.=')';
        } else {
            my @lda=($ld=~m/\d/g);
            my @uda=($ud=~m/\d/g);
-           my $i; $j=0; $notdone=1;
+           my $i; 
+           my $j=0; 
+           my $notdone=1;
            for ($i=0;($i<=$#lda)&&($notdone);$i++) {
                if ($lda[$i]==$uda[$i]) {
 		   $num.=$lda[$i];
@@ -159,53 +861,422 @@ sub mask {
                }
                $num.=')';
            } else {
-               if ($lda[$#lda]!=$uda[$#uda]) {
-                  $num.='['.$lda[$#lda].'-'.$uda[$#uda].']';
+               if ($lda[-1]!=$uda[-1]) {
+                  $num.='['.$lda[-1].'-'.$uda[-1].']';
 	       }
            }
        }
     }
-    return '^'.$alpha.$num."\$";
+    my $expression ='^'.$alpha.$num."\$";
+    $memoizer{$key} = $expression;
+    return $expression;
+}
+
+}
+
+sub add_hash_to_safe {
+    my $self = shift;
+    my $code = <<'END';
+#-------------------------------------------------------
+
+=item UWCALC(hashname,modules,units,date) 
+
+returns the proportion of the module 
+weights not previously completed by the student.
+
+=over 4
+
+=item hashname 
+
+name of the hash the module dates have been inserted into
+
+=item modules 
+
+reference to a cell which contains a comma deliminated list of modules 
+covered by the assignment.
+
+=item units 
+
+reference to a cell which contains a comma deliminated list of module 
+weights with respect to the assignment
+
+=item date 
+
+reference to a cell which contains the date the assignment was completed.
+
+=back 
+
+=cut
+
+#-------------------------------------------------------
+sub UWCALC {
+    my ($hashname,$modules,$units,$date) = @_;
+    my @Modules = split(/,/,$modules);
+    my @Units   = split(/,/,$units);
+    my $total_weight;
+    foreach (@Units) {
+	$total_weight += $_;
+    }
+    my $usum=0;
+    for (my $i=0; $i<=$#Modules; $i++) {
+	if (&HASH($hashname,$Modules[$i]) eq $date) {
+	    $usum += $Units[$i];
+	}
+    }
+    return $usum/$total_weight;
+}
+
+#-------------------------------------------------------
+
+=item CDLSUM(list) 
+
+returns the sum of the elements in a cell which contains
+a Comma Deliminate List of numerical values.
+'list' is a reference to a cell which contains a comma deliminated list.
+
+=cut
+
+#-------------------------------------------------------
+sub CDLSUM {
+    my ($list)=@_;
+    my $sum;
+    foreach (split/,/,$list) {
+	$sum += $_;
+    }
+    return $sum;
+}
+
+#-------------------------------------------------------
+
+=item CDLITEM(list,index) 
+
+returns the item at 'index' in a Comma Deliminated List.
+
+=over 4
+
+=item list
+
+reference to a cell which contains a comma deliminated list.
+
+=item index 
+
+the Perl index of the item requested (first element in list has
+an index of 0) 
+
+=back
+
+=cut
+
+#-------------------------------------------------------
+sub CDLITEM {
+    my ($list,$index)=@_;
+    my @Temp = split/,/,$list;
+    return $Temp[$index];
+}
+
+#-------------------------------------------------------
+
+=item CDLHASH(name,key,value) 
+
+loads a comma deliminated list of keys into
+the hash 'name', all with a value of 'value'.
+
+=over 4
+
+=item name  
+
+name of the hash.
+
+=item key
+
+(a pointer to) a comma deliminated list of keys.
+
+=item value
+
+a single value to be entered for each key.
+
+=back
+
+=cut
+
+#-------------------------------------------------------
+sub CDLHASH {
+    my ($name,$key,$value)=@_;
+    my @Keys;
+    my @Values;
+    # Check to see if we have multiple $key values
+    if ($key =~ /[A-z](\-[A-z])?\d+(\-\d+)?/) {
+	my $keymask = &mask($key);
+	# Assume the keys are addresses
+	my @Temp = grep /$keymask/,keys(%sheet_values);
+	@Keys = $sheet_values{@Temp};
+    } else {
+	$Keys[0]= $key;
+    }
+    my @Temp;
+    foreach $key (@Keys) {
+	@Temp = (@Temp, split/,/,$key);
+    }
+    @Keys = @Temp;
+    if ($value =~ /[A-z](\-[A-z])?\d+(\-\d+)?/) {
+	my $valmask = &mask($value);
+	my @Temp = grep /$valmask/,keys(%sheet_values);
+	@Values =$sheet_values{@Temp};
+    } else {
+	$Values[0]= $value;
+    }
+    $value = $Values[0];
+    # Add values to hash
+    for (my $i = 0; $i<=$#Keys; $i++) {
+	my $key   = $Keys[$i];
+	if (! exists ($hashes{$name}->{$key})) {
+	    $hashes{$name}->{$key}->[0]=$value;
+	} else {
+	    my @Temp = sort(@{$hashes{$name}->{$key}},$value);
+	    $hashes{$name}->{$key} = \@Temp;
+	}
+    }
+    return "hash '$name' updated";
 }
 
+#-------------------------------------------------------
+
+=item GETHASH(name,key,index) 
+
+returns the element in hash 'name' 
+reference by the key 'key', at index 'index' in the values list.
+
+=cut
+
+#-------------------------------------------------------
+sub GETHASH {
+    my ($name,$key,$index)=@_;
+    if (! defined($index)) {
+	$index = 0;
+    }
+    if ($key =~ /^[A-z]\d+$/) {
+	$key = $sheet_values{$key};
+    }
+    return $hashes{$name}->{$key}->[$index];
+}
+
+#-------------------------------------------------------
+
+=item CLEARHASH(name) 
+
+clears all the values from the hash 'name'
+
+=item CLEARHASH(name,key) 
+
+clears all the values from the hash 'name' associated with the given key.
+
+=cut
+
+#-------------------------------------------------------
+sub CLEARHASH {
+    my ($name,$key)=@_;
+    if (defined($key)) {
+	if (exists($hashes{$name}->{$key})) {
+	    $hashes{$name}->{$key}=undef;
+	    return "hash '$name' key '$key' cleared";
+	}
+    } else {
+	if (exists($hashes{$name})) {
+	    $hashes{$name}=undef;
+	    return "hash '$name' cleared";
+	}
+    }
+    return "Error in clearing hash";
+}
+
+#-------------------------------------------------------
+
+=item HASH(name,key,value) 
+
+loads values into an internal hash.  If a key 
+already has a value associated with it, the values are sorted numerically.  
+
+=item HASH(name,key) 
+
+returns the 0th value in the hash 'name' associated with 'key'.
+
+=cut
+
+#-------------------------------------------------------
+sub HASH {
+    my ($name,$key,$value)=@_;
+    my @Keys;
+    undef @Keys;
+    my @Values;
+    # Check to see if we have multiple $key values
+    if ($key =~ /[A-z](\-[A-z])?\d+(\-\d+)?/) {
+	my $keymask = &mask($key);
+	# Assume the keys are addresses
+	my @Temp = grep /$keymask/,keys(%sheet_values);
+	@Keys = $sheet_values{@Temp};
+    } else {
+	$Keys[0]= $key;
+    }
+    # If $value is empty, return the first value associated 
+    # with the first key.
+    if (! $value) {
+	return $hashes{$name}->{$Keys[0]}->[0];
+    }
+    # Check to see if we have multiple $value(s) 
+    if ($value =~ /[A-z](\-[A-z])?\d+(\-\d+)?/) {
+	my $valmask = &mask($value);
+	my @Temp = grep /$valmask/,keys(%sheet_values);
+	@Values =$sheet_values{@Temp};
+    } else {
+	$Values[0]= $value;
+    }
+    # Add values to hash
+    for (my $i = 0; $i<=$#Keys; $i++) {
+	my $key   = $Keys[$i];
+	my $value = ($i<=$#Values ? $Values[$i] : $Values[0]);
+	if (! exists ($hashes{$name}->{$key})) {
+	    $hashes{$name}->{$key}->[0]=$value;
+	} else {
+	    my @Temp = sort(@{$hashes{$name}->{$key}},$value);
+	    $hashes{$name}->{$key} = \@Temp;
+	}
+    }
+    return $Values[-1];
+}
+END
+    $self->{'safe'}->reval($code);
+    return;
+}
+
+sub initsheet {
+    my $safeeval = new Safe(shift);
+    my $safehole = new Safe::Hole;
+    $safeeval->permit("entereval");
+    $safeeval->permit(":base_math");
+    $safeeval->permit("sort");
+    $safeeval->deny(":base_io");
+    $safehole->wrap(\&Apache::lonnet::EXT,$safeeval,'&EXT');
+    $safehole->wrap(\&mask,$safeeval,'&mask');
+    $safeeval->share('$@');
+    my $code=<<'ENDDEFS';
+# ---------------------------------------------------- Inside of the safe space
+#
+# f: formulas
+# t: intermediate format (variable references expanded)
+# v: output values
+# c: preloaded constants (A-column)
+# rl: row label
+# os: other spreadsheets (for student spreadsheet only)
+
+undef %sheet_values;   # Holds the (computed, final) values for the sheet
+    # This is only written to by &calc, the spreadsheet computation routine.
+    # It is read by many functions
+undef %t; # Holds the values of the spreadsheet temporarily. Set in &sett, 
+    # which does the translation of strings like C5 into the value in C5.
+    # Used in &calc - %t holds the values that are actually eval'd.
+undef %f;    # Holds the formulas for each cell.  This is the users
+    # (spreadsheet authors) data for each cell.
+undef %c; # Holds the constants for a sheet.  In the assessment
+    # sheets, this is the A column.  Used in &MINPARM, &MAXPARM, &expandnamed,
+    # &sett, and &constants.  There is no &getconstants.
+    # &constants is called by &loadstudent, &loadcourse, &load assessment,
+undef @os;  # Holds the names of other spreadsheets - this is used to specify
+    # the spreadsheets that are available for the assessment sheet.
+    # Set by &setothersheets.  &setothersheets is called by &handler.  A
+    # related subroutine is &othersheets.
+$errorlog = '';
+
+$maxrow = 0;
+$type = '';
+
+# filename/reference of the sheet
+$filename = '';
+
+# user data
+$uname = '';
+$uhome = '';
+$udom  = '';
+
+# course data
+
+$csec = '';
+$chome= '';
+$cnum = '';
+$cdom = '';
+$cid  = '';
+$coursefilename  = '';
+
+# symb
+
+$usymb = '';
+
+# error messages
+$errormsg = '';
+
+#-------------------------------------------------------
+
+=item NUM(range)
+
+returns the number of items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub NUM {
-    my $mask=mask(@_);
-    my $num=0;
-    map {
-        $num++;
-    } grep /$mask/,keys %v;
+    my $mask=&mask(@_);
+    my $num= $#{@{grep(/$mask/,keys(%sheet_values))}}+1;
     return $num;   
 }
 
 sub BIN {
     my ($low,$high,$lower,$upper)=@_;
-    my $mask=mask($lower,$upper);
+    my $mask=&mask($lower,$upper);
     my $num=0;
-    map {
-        if (($v{$_}>=$low) && ($v{$_}<=$high)) {
+    foreach (grep /$mask/,keys(%sheet_values)) {
+        if (($sheet_values{$_}>=$low) && ($sheet_values{$_}<=$high)) {
             $num++;
         }
-    } grep /$mask/,keys %v;
+    }
     return $num;   
 }
 
 
+#-------------------------------------------------------
+
+=item SUM(range)
+
+returns the sum of items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub SUM {
-    my $mask=mask(@_);
+    my $mask=&mask(@_);
     my $sum=0;
-    map {
-        $sum+=$v{$_};
-    } grep /$mask/,keys %v;
+    foreach (grep /$mask/,keys(%sheet_values)) {
+        $sum+=$sheet_values{$_};
+    }
     return $sum;   
 }
 
+#-------------------------------------------------------
+
+=item MEAN(range)
+
+compute the average of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub MEAN {
-    my $mask=mask(@_);
-    my $sum=0; my $num=0;
-    map {
-        $sum+=$v{$_};
+    my $mask=&mask(@_);
+#    $errorlog.='(mask = '.$mask.' )';
+    my $sum=0; 
+    my $num=0;
+    foreach (grep /$mask/,keys(%sheet_values)) {
+        $sum+=$sheet_values{$_};
         $num++;
-    } grep /$mask/,keys %v;
+    }
     if ($num) {
        return $sum/$num;
     } else {
@@ -213,58 +1284,107 @@ sub MEAN {
     }   
 }
 
+#-------------------------------------------------------
+
+=item STDDEV(range)
+
+compute the standard deviation of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub STDDEV {
-    my $mask=mask(@_);
+    my $mask=&mask(@_);
+#    $errorlog.='(mask = '.$mask.' )';
     my $sum=0; my $num=0;
-    map {
-        $sum+=$v{$_};
+    foreach (grep /$mask/,keys(%sheet_values)) {
+        $sum+=$sheet_values{$_};
         $num++;
-    } grep /$mask/,keys %v;
+    }
     unless ($num>1) { return undef; }
     my $mean=$sum/$num;
     $sum=0;
-    map {
-        $sum+=($v{$_}-$mean)**2;
-    } grep /$mask/,keys %v;
+    foreach (grep /$mask/,keys(%sheet_values)) {
+        $sum+=($sheet_values{$_}-$mean)**2;
+    }
     return sqrt($sum/($num-1));    
 }
 
+#-------------------------------------------------------
+
+=item PROD(range)
+
+compute the product of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub PROD {
-    my $mask=mask(@_);
+    my $mask=&mask(@_);
     my $prod=1;
-    map {
-        $prod*=$v{$_};
-    } grep /$mask/,keys %v;
+    foreach (grep /$mask/,keys(%sheet_values)) {
+        $prod*=$sheet_values{$_};
+    }
     return $prod;   
 }
 
+#-------------------------------------------------------
+
+=item MAX(range)
+
+compute the maximum of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub MAX {
-    my $mask=mask(@_);
+    my $mask=&mask(@_);
     my $max='-';
-    map {
-        unless ($max) { $max=$v{$_}; }
-        if (($v{$_}>$max) || ($max eq '-')) { $max=$v{$_}; }
-    } grep /$mask/,keys %v;
+    foreach (grep /$mask/,keys(%sheet_values)) {
+        unless ($max) { $max=$sheet_values{$_}; }
+        if (($sheet_values{$_}>$max) || ($max eq '-')) { $max=$sheet_values{$_}; }
+    } 
     return $max;   
 }
 
+#-------------------------------------------------------
+
+=item MIN(range)
+
+compute the minimum of the items in the range.
+
+=cut
+
+#-------------------------------------------------------
 sub MIN {
-    my $mask=mask(@_);
+    my $mask=&mask(@_);
     my $min='-';
-    map {
-        unless ($max) { $max=$v{$_}; }
-        if (($v{$_}<$min) || ($min eq '-')) { $min=$v{$_}; }
-    } grep /$mask/,keys %v;
+    foreach (grep /$mask/,keys(%sheet_values)) {
+        unless ($max) { $max=$sheet_values{$_}; }
+        if (($sheet_values{$_}<$min) || ($min eq '-')) { 
+            $min=$sheet_values{$_}; 
+        }
+    }
     return $min;   
 }
 
+#-------------------------------------------------------
+
+=item SUMMAX(num,lower,upper)
+
+compute the sum of the largest 'num' items in the range from
+'lower' to 'upper'
+
+=cut
+
+#-------------------------------------------------------
 sub SUMMAX {
     my ($num,$lower,$upper)=@_;
-    my $mask=mask($lower,$upper);
+    my $mask=&mask($lower,$upper);
     my @inside=();
-    map {
-	$inside[$#inside+1]=$v{$_};
-    } grep /$mask/,keys %v;
+    foreach (grep /$mask/,keys(%sheet_values)) {
+	push (@inside,$sheet_values{$_});
+    }
     @inside=sort(@inside);
     my $sum=0; my $i;
     for ($i=$#inside;(($i>$#inside-$num) && ($i>=0));$i--) { 
@@ -273,13 +1393,23 @@ sub SUMMAX {
     return $sum;   
 }
 
+#-------------------------------------------------------
+
+=item SUMMIN(num,lower,upper)
+
+compute the sum of the smallest 'num' items in the range from
+'lower' to 'upper'
+
+=cut
+
+#-------------------------------------------------------
 sub SUMMIN {
     my ($num,$lower,$upper)=@_;
-    my $mask=mask($lower,$upper);
+    my $mask=&mask($lower,$upper);
     my @inside=();
-    map {
-	$inside[$#inside+1]=$v{$_};
-    } grep /$mask/,keys %v;
+    foreach (grep /$mask/,keys(%sheet_values)) {
+	$inside[$#inside+1]=$sheet_values{$_};
+    }
     @inside=sort(@inside);
     my $sum=0; my $i;
     for ($i=0;(($i<$num) && ($i<=$#inside));$i++) { 
@@ -288,1086 +1418,1958 @@ sub SUMMIN {
     return $sum;   
 }
 
-sub sett {
-    %t=();
-    my $pattern='';
-    if ($sheettype eq 'assesscalc') {
-	$pattern='A';
-    } else {
-        $pattern='[A-Z]';
+#-------------------------------------------------------
+
+=item MINPARM(parametername)
+
+Returns the minimum value of the parameters matching the parametername.
+parametername should be a string such as 'duedate'.
+
+=cut
+
+#-------------------------------------------------------
+sub MINPARM {
+    my ($expression) = @_;
+    my $min = undef;
+    study($expression);
+    foreach $parameter (keys(%c)) {
+        next if ($parameter !~ /$expression/);
+        if ((! defined($min)) || ($min > $c{$parameter})) {
+            $min = $c{$parameter} 
+        }
     }
-    map {
-	if ($_=~/template\_(\w)/) {
-	  my $col=$1;
-          unless ($col=~/^$pattern/) {
-            map {
-	      if ($_=~/A(\d+)/) {
-		my $trow=$1;
-                if ($trow) {
-		    my $lb=$col.$trow;
-                    $t{$lb}=$f{'template_'.$col};
-                    $t{$lb}=~s/\#/$trow/g;
-                    $t{$lb}=~s/\.\.+/\,/g;
-                    $t{$lb}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
-                }
-	      }
-            } keys %f;
-	  }
-      }
-    } keys %f;
-    map {
-	if (($f{$_}) && ($_!~/template\_/)) {
-            if ($_=~/^$pattern/) {
-	        unless ($f{$_}=~/^\!/) {
-		    $t{$_}=$c{$_};
-                }
-            } else {
-	       $t{$_}=$f{$_};
-               $t{$_}=~s/\.\.+/\,/g;
-               $t{$_}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
-            }
+    return $min;
+}
+
+#-------------------------------------------------------
+
+=item MAXPARM(parametername)
+
+Returns the maximum value of the parameters matching the input parameter name.
+parametername should be a string such as 'duedate'.
+
+=cut
+
+#-------------------------------------------------------
+sub MAXPARM {
+    my ($expression) = @_;
+    my $max = undef;
+    study($expression);
+    foreach $parameter (keys(%c)) {
+        next if ($parameter !~ /$expression/);
+        if ((! defined($min)) || ($max < $c{$parameter})) {
+            $max = $c{$parameter} 
         }
-    } keys %f;
-    $t{'A0'}=$f{'A0'};
-    $t{'A0'}=~s/\.\.+/\,/g;
-    $t{'A0'}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
+    }
+    return $max;
 }
 
 sub calc {
-    %v=();
-    &sett();
+#    $errorlog .= "\%t has ".(keys(%t))." keys\n";
+    %sheet_values = %t; # copy %t into %sheet_values.
+#    $errorlog .= "\%sheet_values has ".(keys(%sheet_values))." keys\n";
     my $notfinished=1;
+    my $lastcalc='';
     my $depth=0;
     while ($notfinished) {
 	$notfinished=0;
-        map {
-            my $old=$v{$_};
-            $v{$_}=eval($t{$_});
+        while (my ($cell,$value) = each(%t)) {
+            my $old=$sheet_values{$cell};
+            $sheet_values{$cell}=eval $value;
 	    if ($@) {
-		%v=();
-                return $@;
+		undef %sheet_values;
+                return $cell.': '.$@;
+            }
+	    if ($sheet_values{$cell} ne $old) { 
+                $notfinished=1; 
+                $lastcalc=$cell; 
             }
-	    if ($v{$_} ne $old) { $notfinished=1; }
-        } keys %t;
+        }
         $depth++;
         if ($depth>100) {
-	    %v=();
-            return 'Maximum calculation depth exceeded';
+	    undef %sheet_values;
+            return $lastcalc.': Maximum calculation depth exceeded';
         }
     }
     return '';
 }
 
-sub templaterow {
-    my @cols=();
-    $cols[0]='<b><font size=+1>Template</font></b>';
-    map {
-        my $fm=$f{'template_'.$_};
-        $fm=~s/[\'\"]/\&\#34;/g;
-        $cols[$#cols+1]="'template_$_','$fm'".'___eq___'.$fm;
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-       'a','b','c','d','e','f','g','h','i','j','k','l','m',
-       'n','o','p','q','r','s','t','u','v','w','x','y','z');
-    return @cols;
-}
-
-sub outrowassess {
-    my $n=shift;
-    my @cols=();
-    if ($n) {
-       $cols[0]=$rl{$f{'A'.$n}};
-    } else {
-       $cols[0]='<b><font size=+1>Export</font></b>';
-    }
-    map {
-        my $fm=$f{$_.$n};
-        $fm=~s/[\'\"]/\&\#34;/g;
-        $cols[$#cols+1]="'$_$n','$fm'".'___eq___'.$v{$_.$n};
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-       'a','b','c','d','e','f','g','h','i','j','k','l','m',
-       'n','o','p','q','r','s','t','u','v','w','x','y','z');
-    return @cols;
-}
-
-sub outrow {
-    my $n=shift;
-    my @cols=();
-    if ($n) {
-       $cols[0]=$rl{$f{'A'.$n}};
-    } else {
-       $cols[0]='<b><font size=+1>Export</font></b>';
-    }
-    map {
-        my $fm=$f{$_.$n};
-        $fm=~s/[\'\"]/\&\#34;/g;
-        $cols[$#cols+1]="'$_$n','$fm'".'___eq___'.$v{$_.$n};
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-       'a','b','c','d','e','f','g','h','i','j','k','l','m',
-       'n','o','p','q','r','s','t','u','v','w','x','y','z');
-    return @cols;
-}
-
-sub exportrowa {
-    my @exportarray=();
-    map {
-	$exportarray[$#exportarray+1]=$v{$_.'0'};
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z');
-    return @exportarray;
-}
-
 # ------------------------------------------- End of "Inside of the safe space"
 ENDDEFS
     $safeeval->reval($code);
     return $safeeval;
 }
 
-# ------------------------------------------------ Add or change formula values
-
-sub setformulas {
-    my ($safeeval,%f)=@_;
-    %{$safeeval->varglob('f')}=%f;
-}
-
-# ------------------------------------------------ Add or change formula values
 
-sub setconstants {
-    my ($safeeval,%c)=@_;
-    %{$safeeval->varglob('c')}=%c;
-}
-
-# ------------------------------------------------ Add or change formula values
-
-sub setrowlabels {
-    my ($safeeval,%rl)=@_;
-    %{$safeeval->varglob('rl')}=%rl;
-}
-
-# ------------------------------------------------------- Calculate spreadsheet
-
-sub calcsheet {
-    my $safeeval=shift;
-    $safeeval->reval('&calc();');
+#
+# expandnamed used to reside in the safe space
+#
+sub expandnamed {
+    my $self = shift;
+    my $expression=shift;
+    if ($expression=~/^\&/) {
+	my ($func,$var,$formula)=($expression=~/^\&(\w+)\(([^\;]+)\;(.*)\)/);
+	my @vars=split(/\W+/,$formula);
+        my %values=();
+	foreach my $varname ( @vars ) {
+            if ($varname=~/\D/) {
+               $formula=~s/$varname/'$c{\''.$varname.'\'}'/ge;
+               $varname=~s/$var/\(\\w\+\)/g;
+	       foreach (keys(%{$self->{'constants'}})) {
+		  if ($_=~/$varname/) {
+		      $values{$1}=1;
+                  }
+               }
+	    }
+        }
+        if ($func eq 'EXPANDSUM') {
+            my $result='';
+	    foreach (keys(%values)) {
+                my $thissum=$formula;
+                $thissum=~s/$var/$_/g;
+                $result.=$thissum.'+';
+            } 
+            $result=~s/\+$//;
+            return $result;
+        } else {
+	    return 0;
+        }
+    } else {
+        # it is not a function, so it is a parameter name
+        # We should do the following:
+        #    1. Take the list of parameter names
+        #    2. look through the list for ones that match the parameter we want
+        #    3. If there are no collisions, return the one that matches
+        #    4. If there is a collision, return 'bad parameter name error'
+        my $returnvalue = '';
+        my @matches = ();
+        $#matches = -1;
+        study $expression;
+        my $parameter;
+        foreach $parameter (keys(%{$self->{'constants'}})) {
+            push @matches,$parameter if ($parameter =~ /$expression/);
+        }
+        if (scalar(@matches) == 0) {
+            $returnvalue = 'unmatched parameter: '.$parameter;
+        } elsif (scalar(@matches) == 1) {
+            # why do we not do this lookup here, instead of delaying it?
+            $returnvalue = '$c{\''.$matches[0].'\'}';
+        } elsif (scalar(@matches) > 0) {
+            # more than one match.  Look for a concise one
+            $returnvalue =  "'non-unique parameter name : $expression'";
+            foreach (@matches) {
+                if (/^$expression$/) {
+                    # why do we not do this lookup here?
+                    $returnvalue = '$c{\''.$_.'\'}';
+                }
+            }
+        } else {
+            # There was a negative number of matches, which indicates 
+            # something is wrong with reality.  Better warn the user.
+            $returnvalue = 'bizzare parameter: '.$parameter;
+        }
+        return $returnvalue;
+    }
 }
 
-# ------------------------------------------------------------------ Get values
-
-sub getvalues {
-    my $safeeval=shift;
-    return $safeeval->reval('%v');
+#
+# sett used to reside in the safe space
+#
+sub sett {
+    my $self = shift;
+    my %t=();
+    my $pattern='';
+    if ($self->{'type'} eq 'assesscalc') {
+	$pattern='A';
+    } else {
+        $pattern='[A-Z]';
+    }
+    # Deal with the template row
+    foreach my $col ($self->template_cells()) {
+        next if ($col=~/^$pattern/);
+        foreach my $trow ($self->rows()) {
+            # Get the name of this cell
+            my $lb=$col.$trow;
+            # Grab the template declaration
+            $t{$lb}=$self->formula('template_'.$col);
+            # Replace '#' with the row number
+            $t{$lb}=~s/\#/$trow/g;
+            # Replace '....' with ','
+            $t{$lb}=~s/\.\.+/\,/g;
+            # Replace 'A0' with the value from 'A0'
+            $t{$lb}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$sheet_values\{\'$2\'\}/g;
+            # Replace parameters
+            $t{$lb}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.$self->expandnamed($2)/ge;
+        }
+    }
+    # Deal with the normal cells
+    foreach ($self->formulas_keys()) {
+	next if ($_=~/template\_/);
+        if  (($_=~/^$pattern(\d+)/) && ($1)) {
+            if ($self->formula($_) !~ /^\!/) {
+                $t{$_}=$self->{'constants'}->{$_};
+            }
+        } else {
+            $t{$_}=$self->formula($_);
+            $t{$_}=~s/\.\.+/\,/g;
+            $t{$_}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$sheet_values\{\'$2\'\}/g;
+            $t{$_}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.$self->expandnamed($2)/ge;
+        }
+    }
+    # For inserted lines, [B-Z] is also valid
+    if ($self->{'type'} ne 'assesscalc') {
+        foreach ($self->formulas_keys()) {
+            next if ($_ !~ /[B-Z](\d+)/);
+            next if ($self->formula('A'.$1) !~ /^[\~\-]/);
+            $t{$_}=$self->formula($_);
+            $t{$_}=~s/\.\.+/\,/g;
+            $t{$_}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$sheet_values\{\'$2\'\}/g;
+            $t{$_}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.$self->expandnamed($2)/ge;
+        }
+    }
+    # For some reason 'A0' gets special treatment...  This seems superfluous
+    # but I imagine it is here for a reason.
+    $t{'A0'}=$self->formula('A0');
+    $t{'A0'}=~s/\.\.+/\,/g;
+    $t{'A0'}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$sheet_values\{\'$2\'\}/g;
+    $t{'A0'}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.$self->expandnamed($2)/ge;
+    # Put %t into the safe space
+    %{$self->{'safe'}->varglob('t')}=%t;
 }
 
-# ---------------------------------------------------------------- Get formulas
 
-sub getformulas {
-    my $safeeval=shift;
-    return %{$safeeval->varglob('f')};
+###########################################
+###          Row output routines        ###
+###########################################
+#
+# get_row: Produce output row n from sheet by calling the appropriate routine
+#
+sub get_row {
+    my $self = shift;
+    my ($n) = @_;
+    my ($rowlabel,@rowdata);
+    if ($n eq '-') { 
+        ($rowlabel,@rowdata) = $self->templaterow();
+    } elsif ($self->{'type'} eq 'studentcalc') {
+        ($rowlabel,@rowdata) = $self->outrowassess($n);
+    } else {
+        ($rowlabel,@rowdata) = $self->outrow($n);
+    }
+    return ($rowlabel,@rowdata);
 }
 
-# -------------------------------------------------------------------- Get type
-
-sub gettype {
-    my $safeeval=shift;
-    return $safeeval->reval('$sheettype');
+sub templaterow {
+    my $self = shift;
+    my @cols=();
+    my $rowlabel = 'Template</td><td>&nbsp;';
+    foreach my $n ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+                   'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
+                   'a','b','c','d','e','f','g','h','i','j','k','l','m',
+                   'n','o','p','q','r','s','t','u','v','w','x','y','z') {
+        push(@cols,{ name    => 'template_'.$_,
+                     formula => $self->formula('template_'.$n),
+                     value   => $self->value('template_'.$n) });
+    }
+    return ($rowlabel,@cols);
 }
 
-# ------------------------------------------------------------------ Set maxrow
-
-sub setmaxrow {
-    my ($safeeval,$row)=@_;
-    $safeeval->reval('$maxrow='.$row.';');
+sub outrowassess {
+    my $self = shift;
+    # $n is the current row number
+    my ($n) = @_;
+    my @cols=();
+    my $rowlabel='';
+    if ($n) {
+        my ($usy,$ufn)=split(/__&&&\__/,$self->formula('A'.$n));
+        if (exists($self->{'rowlabel'}->{$usy})) {
+            # This is dumb, but we need the information when we output
+            # the html version of the studentcalc spreadsheet for the
+            # links to the assesscalc sheets.
+            $rowlabel = $self->{'rowlabel'}->{$usy}.':'.
+                &Apache::lonnet::escape($ufn);
+        } else { 
+            $rowlabel = '';
+        }
+    } elsif ($ENV{'request.role'} =~ /^st\./) {
+        $rowlabel = 'Summary</td><td>0';
+    } else {
+        $rowlabel = 'Export</td><td>0';
+    }
+    foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+	     'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
+	     'a','b','c','d','e','f','g','h','i','j','k','l','m',
+	     'n','o','p','q','r','s','t','u','v','w','x','y','z') {
+        push(@cols,{ name    => $_.$n,
+                     formula => $self->formula($_.$n),
+                     value   => $self->value($_.$n)});
+    }
+    return ($rowlabel,@cols);
 }
 
-# ------------------------------------------------------------------ Get maxrow
-
-sub getmaxrow {
-    my $safeeval=shift;
-    return $safeeval->reval('$maxrow');
+sub outrow {
+    my $self = shift;
+    my ($n)=@_;
+    my @cols=();
+    my $rowlabel;
+    if ($n) {
+        $rowlabel = $self->{'rowlabel'}->{$self->formula('A'.$n)};
+    } else {
+        if ($self->{'type'} eq 'classcalc') {
+            $rowlabel = 'Summary</td><td>0';
+        } else {
+            $rowlabel = 'Export</td><td>0';
+        }
+    }
+    foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+	     'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
+	     'a','b','c','d','e','f','g','h','i','j','k','l','m',
+	     'n','o','p','q','r','s','t','u','v','w','x','y','z') {
+        push(@cols,{ name    => $_.$n,
+                     formula => $self->formula($_.$n),
+                     value   => $self->value($_.$n)});
+    }
+    return ($rowlabel,@cols);
+}
+
+########################################################
+####         Spreadsheet calculation methods       #####
+########################################################
+#
+# calcsheet: makes all the calls to compute the spreadsheet.
+#
+sub calcsheet {
+    my $self = shift;
+    $self->sync_safe_space();
+    $self->clear_errorlog();
+    $self->sett();
+    my $result =  $self->{'safe'}->reval('&calc();');
+    %{$self->{'values'}} = %{$self->{'safe'}->varglob('sheet_values')};
+#    $self->logthis($self->get_errorlog());
+    return $result;
+}
+
+##
+## sync_safe_space:  Called by calcsheet to make sure all the data we 
+#  need to calculate is placed into the safe space
+##
+sub sync_safe_space {
+    my $self = shift;
+    # Inside the safe space 'formulas' has a diabolical alter-ego named 'f'.
+    %{$self->{'safe'}->varglob('f')}=%{$self->{'formulas'}};
+    # 'constants' leads a peaceful hidden life of 'c'.
+    %{$self->{'safe'}->varglob('c')}=%{$self->{'constants'}};
+    # 'othersheets' hides as 'os', a disguise few can penetrate.
+    @{$self->{'safe'}->varglob('os')}=@{$self->{'othersheets'}};
+}
+
+##
+## Retrieve the error log from the safe space (used for debugging)
+##
+sub get_errorlog {
+    my $self = shift;
+    $self->{'errorlog'} = ${$self->{'safe'}->varglob('errorlog')};
+    return $self->{'errorlog'};
+}
+
+##
+## Clear the error log inside the safe space
+##
+sub clear_errorlog {
+    my $self = shift;
+    ${$self->{'safe'}->varglob('errorlog')} = '';
+    $self->{'errorlog'} = '';
 }
 
-# ---------------------------------------------------------------- Set filename
 
-sub setfilename {
-    my ($safeeval,$fn)=@_;
-    $safeeval->reval('$filename="'.$fn.'";');
+########################################################
+#### Spreadsheet content retrieval/setting methods #####
+########################################################
+##
+## constants:  either set or get the constants
+##
+##
+sub constants {
+    my $self=shift;
+    my ($constants) = @_;
+    if (defined($constants)) {
+        if (! ref($constants)) {
+            my %tmp = @_;
+            $constants = \%tmp;
+        }
+        $self->{'constants'} = $constants;
+        return;
+    } else {
+        return %{$self->{'constants'}};
+    }
 }
-
-# ---------------------------------------------------------------- Get filename
-
-sub getfilename {
-    my $safeeval=shift;
-    return $safeeval->reval('$filename');
+    
+##
+## formulas: either set or get the formulas
+##
+sub formulas {
+    my $self=shift;
+    my ($formulas) = @_;
+    if (defined($formulas)) {
+        if (! ref($formulas)) {
+            my %tmp = @_;
+            $formulas = \%tmp;
+        }
+        $self->{'formulas'} = $formulas;
+        $self->{'rows'} = [];
+        $self->{'template_cells'} = [];
+        return;
+    } else {
+        return %{$self->{'formulas'}};
+    }
 }
 
-# --------------------------------------------------------------- Get course ID
-
-sub getcid {
-    my $safeeval=shift;
-    return $safeeval->reval('$cid');
+##
+## formulas_keys:  Return the keys to the formulas hash.
+##
+sub formulas_keys {
+    my $self = shift;
+    my @keys = keys(%{$self->{'formulas'}});
+    return keys(%{$self->{'formulas'}});
+}
+
+##
+## formula:  Return the formula for a given cell in the spreadsheet
+## returns '' if the cell does not have a formula or does not exist
+##
+sub formula {
+    my $self = shift;
+    my $cell = shift;
+    if (defined($cell) && exists($self->{'formulas'}->{$cell})) {
+        return $self->{'formulas'}->{$cell};
+    }
+    return '';
 }
 
-# --------------------------------------------------------- Get course filename
-
-sub getcfn {
-    my $safeeval=shift;
-    return $safeeval->reval('$cfn');
+##
+## logthis: write the input to lonnet.log
+##
+sub logthis {
+    my $self = shift;
+    my $message = shift;
+    &Apache::lonnet::logthis($self->{'type'}.':'.
+                             $self->{'uname'}.':'.$self->{'udom'}.':'.
+                             $message);
+    return;
+}
+
+##
+## dump_formulas_to_log: makes lonnet.log huge...
+##
+sub dump_formulas_to_log {
+    my $self =shift;
+    $self->logthis("Spreadsheet formulas");
+    $self->logthis("--------------------------------------------------------");
+    while (my ($cell, $formula) = each(%{$self->{'formulas'}})) {
+        $self->logthis('    '.$cell.' = '.$formula);
+    }
+    $self->logthis("--------------------------------------------------------");}
+
+##
+## value: returns the computed value of a particular cell
+##
+sub value {
+    my $self = shift;
+    my $cell = shift;
+    if (defined($cell) && exists($self->{'values'}->{$cell})) {
+        return $self->{'values'}->{$cell};
+    }
+    return '';
 }
 
-# ----------------------------------------------------------- Get course number
-
-sub getcnum {
-    my $safeeval=shift;
-    return $safeeval->reval('$cnum');
+##
+## dump_values_to_log: makes lonnet.log huge...
+##
+sub dump_values_to_log {
+    my $self =shift;
+    $self->logthis("Spreadsheet Values");
+    $self->logthis("--------------------------------------------------------");
+    while (my ($cell, $value) = each(%{$self->{'values'}})) {
+        $self->logthis('    '.$cell.' = '.$value);
+    }
+    $self->logthis("--------------------------------------------------------");}
+
+################################
+##      Helper functions      ##
+################################
+##
+## rebuild_stats: rebuilds the rows and template_cells arrays
+##
+sub rebuild_stats {
+    my $self = shift;
+    $self->{'rows'}=[];
+    $self->{'template_cells'}=[];
+    foreach my $cell($self->formulas_keys()) {
+        push(@{$self->{'rows'}},$1) if ($cell =~ /^A(\d+)/ && $1 != 0);
+        push(@{$self->{'template_cells'}},$1) if ($cell =~ /^template_(\w+)/);
+    }
+    return;
+}
+
+##
+## template_cells returns a list of the cells defined in the template row
+##
+sub template_cells {
+    my $self = shift;
+    $self->rebuild_stats() if (!@{$self->{'template_cells'}});
+    return @{$self->{'template_cells'}};
+}
+
+##
+## rows returns a list of the names of cells defined in the A column
+##
+sub rows {
+    my $self = shift;
+    $self->rebuild_stats() if (!@{$self->{'rows'}});
+    return @{$self->{'rows'}};
+}
+
+##
+## Sigh.... 
+##
+sub setothersheets {
+    my $self = shift;
+    my @othersheets = @_;
+    $self->{'othersheets'} = \@othersheets;
+}
+
+##
+## rowlabels: get or set the rowlabels hash from the spreadsheet.
+##
+sub rowlabels {
+    my $self = shift;
+    my ($rowlabel) = @_;
+    if (defined($rowlabel)) {
+        if (! ref($rowlabel)) {
+            my %tmp = @_;
+            $rowlabel = \%tmp;
+        }
+        $self->{'rowlabel'}=$rowlabel;
+        return;
+    } else {
+        return %{$self->{'rowlabel'}} if (defined($self->{'rowlabel'}));
+    }
 }
 
-# ------------------------------------------------------------- Get course home
-
-sub getchome {
-    my $safeeval=shift;
-    return $safeeval->reval('$chome');
+##
+## gettitle: returns a title for the spreadsheet.
+##
+sub gettitle {
+    my $self = shift;
+    if ($self->{'type'} eq 'classcalc') {
+        return $self->{'coursedesc'};
+    } elsif ($self->{'type'} eq 'studentcalc') {
+        return 'Grades for '.$self->{'uname'}.'@'.$self->{'udom'};
+    } elsif ($self->{'type'} eq 'assesscalc') {
+        if (($self->{'usymb'} eq '_feedback') ||
+            ($self->{'usymb'} eq '_evaluation') ||
+            ($self->{'usymb'} eq '_discussion') ||
+            ($self->{'usymb'} eq '_tutoring')) {
+            my $title = $self->{'usymb'};
+            $title =~ s/^_//;
+            $title = ucfirst($title);
+            return $title;
+        }
+        return if (! defined($self->{'mapid'}) || 
+                   $self->{'mapid'} !~ /^\d+$/);
+        my $mapid = $self->{'mapid'};
+        return if (! defined($self->{'resid'}) || 
+                   $self->{'resid'} !~ /^\d+$/);
+        my $resid = $self->{'resid'};
+        my %course_db;
+        tie(%course_db,'GDBM_File',$self->{'coursefilename'}.'.db',
+            &GDBM_READER(),0640);
+        return if (! tied(%course_db));
+        my $key = 'title_'.$mapid.'.'.$resid;
+        my $title = '';
+        if (exists($course_db{$key})) {
+            $title = $course_db{$key};
+        } else {
+            $title = $self->{'usymb'};
+        }
+        untie (%course_db);
+        return $title;
+    }
 }
 
-# ----------------------------------------------------------- Get course domain
-
-sub getcdom {
-    my $safeeval=shift;
-    return $safeeval->reval('$cdom');
+#
+# Export of A-row
+#
+sub exportdata {
+    my $self=shift;
+    my @exportarray=();
+    foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+	     'N','O','P','Q','R','S','T','U','V','W','X','Y','Z') {
+        push(@exportarray,$self->value($_.'0'));
+    } 
+    return @exportarray;
 }
 
-# ---------------------------------------------------------- Get course section
-
-sub getcsec {
-    my $safeeval=shift;
-    return $safeeval->reval('$csec');
+##
+## update_student_sheet: experimental function
+##
+sub update_student_sheet{
+    my $self = shift;
+    my ($r,$c) = @_;
+    # Load in the studentcalc sheet
+    $self->readsheet('default_studentcalc');
+    # Determine the structure (contained assessments, etc) of the sheet
+    $self->updatesheet();
+    # Load in the cached sheets for this student
+    $self->cachedssheets();
+    # Load in the (possibly cached) data from the assessment sheets        
+    $self->loadstudent($r,$c);
+    # Compute the sheet
+    $self->calcsheet();
 }
 
-# --------------------------------------------------------------- Get user name
-
-sub getuname {
-    my $safeeval=shift;
-    return $safeeval->reval('$uname');
+#
+# sort_indicies: returns an ordered list of the rows of the spreadsheet
+#
+sub sort_indicies {
+    my $self = shift;
+    my @sortidx=();
+    #
+    if ($self->{'type'} eq 'classcalc') {
+        my @sortby=(undef);
+        # Skip row 0
+        for (my $row=1;$row<=$self->{'maxrow'};$row++) {
+            my (undef,$sname,$sdom,$fullname,$section,$id) = 
+                split(':',$self->{'rowlabel'}->{$self->formula('A'.$row)});
+            push (@sortby, lc($fullname));
+            push (@sortidx, $row);
+        }
+        @sortidx = sort { $sortby[$a] cmp $sortby[$b]; } @sortidx;
+    } elsif ($self->{'type'} eq 'studentcalc') {
+        my @sortby1=(undef);
+        my @sortby2=(undef);
+        # Skip row 0
+        for (my $row=1;$row<=$self->{'maxrow'};$row++) {
+            my ($key,undef) = split(/__&&&\__/,$self->formula('A'.$row));
+            my $rowlabel = $self->{'rowlabel'}->{$key};
+            my (undef,$symb,$mapid,$resid,$title,$ufn) = 
+                split(':',$rowlabel);
+            $ufn   = &Apache::lonnet::unescape($ufn);
+            $symb  = &Apache::lonnet::unescape($symb);
+            $title = &Apache::lonnet::unescape($title);
+            my ($sequence) = ($symb =~ /\/([^\/]*\.sequence)/);
+            if ($sequence eq '') {
+                $sequence = $symb;
+            }
+            push (@sortby1, $sequence);
+            push (@sortby2, $title);
+            push (@sortidx, $row);
+        }
+        @sortidx = sort { $sortby1[$a] cmp $sortby1[$b] || 
+                              $sortby2[$a] cmp $sortby2[$b] } @sortidx;
+    } else {
+        my @sortby=(undef);
+        # Skip row 0
+        $self->sync_safe_space();
+        for (my $row=1;$row<=$self->{'maxrow'};$row++) {
+            push (@sortby, $self->{'safe'}->reval('$f{"A'.$row.'"}'));
+            push (@sortidx, $row);
+        }
+        @sortidx = sort { $sortby[$a] cmp $sortby[$b]; } @sortidx;
+    }
+    return @sortidx;
 }
 
-# ------------------------------------------------------------- Get user domain
-
-sub getudom {
-    my $safeeval=shift;
-    return $safeeval->reval('$udom');
+#############################################################
+###                                                       ###
+###              Spreadsheet Output Routines              ###
+###                                                       ###
+#############################################################
+
+############################################
+##         HTML output routines           ##
+############################################
+sub html_editable_cell {
+    my ($cell,$bgcolor) = @_;
+    my $result;
+    my ($name,$formula,$value);
+    if (defined($cell)) {
+        $name    = $cell->{'name'};
+        $formula = $cell->{'formula'};
+        $value   = $cell->{'value'};
+    }
+    $name    = '' if (! defined($name));
+    $formula = '' if (! defined($formula));
+    if (! defined($value)) {
+        $value = '<font color="'.$bgcolor.'">#</font>';
+        if ($formula ne '') {
+            $value = '<i>undefined value</i>';
+        }
+    } elsif ($value =~ /^\s*$/ ) {
+        $value = '<font color="'.$bgcolor.'">#</font>';
+    } else {
+        $value = &HTML::Entities::encode($value) if ($value !~/&nbsp;/);
+    }
+    # Make the formula safe for outputting
+    $formula =~ s/\'/\"/g;
+    # The formula will be parsed by the browser *twice* before being 
+    # displayed to the user for editing.
+    $formula = &HTML::Entities::encode(&HTML::Entities::encode($formula));
+    # Escape newlines so they make it into the edit window
+    $formula =~ s/\n/\\n/gs;
+    # Glue everything together
+    $result .= "<a href=\"javascript:celledit(\'".
+        $name."','".$formula."');\">".$value."</a>";
+    return $result;
+}
+
+sub html_uneditable_cell {
+    my ($cell,$bgcolor) = @_;
+    my $value = (defined($cell) ? $cell->{'value'} : '');
+    $value = &HTML::Entities::encode($value) if ($value !~/&nbsp;/);
+    return '&nbsp;'.$value.'&nbsp;';
+}
+
+sub outsheet_html  {
+    my $self = shift;
+    my ($r) = @_;
+    my ($num_uneditable,$realm,$row_type);
+    my $requester_is_student = ($ENV{'request.role'} =~ /^st\./);
+    if ($self->{'type'} eq 'assesscalc') {
+        $num_uneditable = 1;
+        $realm = 'Assessment';
+        $row_type = 'Item';
+    } elsif ($self->{'type'} eq 'studentcalc') {
+        $num_uneditable = 26;
+        $realm = 'User';
+        $row_type = 'Assessment';
+    } elsif ($self->{'type'} eq 'classcalc') {
+        $num_uneditable = 26;
+        $realm = 'Course';
+        $row_type = 'Student';
+    } else {
+        return;  # error
+    }
+    ####################################
+    # Print out header table
+    ####################################
+    my $num_left = 52-$num_uneditable;
+    my $tabledata =<<"END";
+<table border="2">
+<tr>
+  <th colspan="2" rowspan="2"><font size="+2">$realm</font></th>
+  <td bgcolor="#FFDDDD" colspan="$num_uneditable">
+      <b><font size="+1">Import</font></b></td>
+  <td colspan="$num_left">
+      <b><font size="+1">Calculations</font></b></td>
+</tr><tr>
+END
+    my $label_num = 0;
+    foreach (split(//,'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz')){
+        if ($label_num<$num_uneditable) { 
+            $tabledata.='<td bgcolor="#FFDDDD">';
+        } else {
+            $tabledata.='<td>';
+        }
+        $tabledata.="<b><font size=+1>$_</font></b></td>";
+        $label_num++;
+    }
+    $tabledata.="</tr>\n";
+    $r->print($tabledata);
+    ####################################
+    # Print out template row
+    ####################################
+    my ($num_cols_output,$row_html,$rowlabel,@rowdata);
+    
+    if (! $requester_is_student) {
+        ($rowlabel,@rowdata) = $self->get_row('-');
+        $row_html = '<tr><td>'.$self->format_html_rowlabel($rowlabel).'</td>';
+        $num_cols_output = 0;
+        foreach my $cell (@rowdata) {
+            if ($requester_is_student || 
+                $num_cols_output++ < $num_uneditable) {
+                $row_html .= '<td bgcolor="#FFDDDD">';
+                $row_html .= &html_uneditable_cell($cell,'#FFDDDD');
+            } else {
+                $row_html .= '<td bgcolor="#EOFFDD">';
+                $row_html .= &html_editable_cell($cell,'#E0FFDD');
+            }
+            $row_html .= '</td>';
+        }
+        $row_html.= "</tr>\n";
+        $r->print($row_html);
+    }
+    ####################################
+    # Print out summary/export row
+    ####################################
+    ($rowlabel,@rowdata) = $self->get_row('0');
+    $row_html = '<tr><td>'.$self->format_html_rowlabel($rowlabel).'</td>';
+    $num_cols_output = 0;
+    foreach my $cell (@rowdata) {
+        if ($num_cols_output++ < 26 && ! $requester_is_student) {
+            $row_html .= '<td bgcolor="#CCCCFF">';
+            $row_html .= &html_editable_cell($cell,'#CCCCFF');
+        } else {
+            $row_html .= '<td bgcolor="#DDCCFF">';
+            $row_html .= &html_uneditable_cell($cell,'#CCCCFF');
+        }
+        $row_html .= '</td>';
+    }
+    $row_html.= "</tr>\n";
+    $r->print($row_html);
+    $r->print('</table>');
+    ####################################
+    # Prepare to output rows
+    ####################################
+    my @Rows = $self->sort_indicies();
+    #
+    # Loop through the rows and output them one at a time
+    my $rows_output=0;
+    foreach my $rownum (@Rows) {
+        my ($rowlabel,@rowdata) = $self->get_row($rownum);
+        next if ($rowlabel =~ /^\s*$/);
+        next if (($self->{'type'} eq 'assesscalc') && 
+                 (! $ENV{'form.showall'})                &&
+                 ($rowdata[0]->{'value'} =~ /^\s*$/));
+        if (! $ENV{'form.showall'} &&
+            $self->{'type'} =~ /^(studentcalc|classcalc)$/) {
+            my $row_is_empty = 1;
+            foreach my $cell (@rowdata) {
+                if ($cell->{'value'} !~  /^\s*$/) {
+                    $row_is_empty = 0;
+                    last;
+                }
+            }
+            next if ($row_is_empty);
+        }
+        #
+        my $defaultbg='#E0FF';
+        #
+        my $row_html ="\n".'<tr><td><b><font size=+1>'.$rownum.
+            '</font></b></td>';
+        #
+        if ($self->{'type'} eq 'classcalc') {
+            $row_html.='<td>'.$self->format_html_rowlabel($rowlabel).'</td>';
+            # Output links for each student?
+            # Nope, that is already done for us in format_html_rowlabel 
+            # (for now)
+        } elsif ($self->{'type'} eq 'studentcalc') {
+            my $ufn = (split(/:/,$rowlabel))[5];
+            $row_html.='<td>'.$self->format_html_rowlabel($rowlabel);
+            $row_html.= '<br>'.
+                '<select name="sel_'.$rownum.'" '.
+                    'onChange="changesheet('.$rownum.')">'.
+                        '<option name="default">Default</option>';
+            foreach (@{$self->{'othersheets'}}) {
+                $row_html.='<option name="'.$_.'"';
+                if ($ufn eq $_) {
+                    $row_html.=' selected';
+                }
+                $row_html.='>'.$_.'</option>';
+            }
+            $row_html.='</select></td>';
+        } elsif ($self->{'type'} eq 'assesscalc') {
+            $row_html.='<td>'.$self->format_html_rowlabel($rowlabel).'</td>';
+        }
+        #
+        my $shown_cells = 0;
+        foreach my $cell (@rowdata) {
+            my $value    = $cell->{'value'};
+            my $formula  = $cell->{'formula'};
+            my $cellname = $cell->{'name'};
+            #
+            my $bgcolor;
+            if ($shown_cells && ($shown_cells/5 == int($shown_cells/5))) {
+                $bgcolor = $defaultbg.'99';
+            } else {
+                $bgcolor = $defaultbg.'DD';
+            }
+            $bgcolor='#FFDDDD' if ($shown_cells < $num_uneditable);
+            #
+            $row_html.='<td bgcolor='.$bgcolor.'>';
+            if ($requester_is_student || $shown_cells < $num_uneditable) {
+                $row_html .= &html_uneditable_cell($cell,$bgcolor);
+            } else {
+                $row_html .= &html_editable_cell($cell,$bgcolor);
+            }
+            $row_html.='</td>';
+            $shown_cells++;
+        }
+        if ($row_html) {
+            if ($rows_output % 25 == 0) {
+                $r->print("</table>\n<br>\n");
+                $r->rflush();
+                $r->print('<table border=2>'.
+                          '<tr><td>&nbsp;<td>'.$row_type.'</td>'.
+                          '<td>'.
+                          join('</td><td>',
+                               (split(//,'ABCDEFGHIJKLMNOPQRSTUVWXYZ'.
+                                      'abcdefghijklmnopqrstuvwxyz'))).
+                          "</td></tr>\n");
+            }
+            $rows_output++;
+            $r->print($row_html);
+        }
+    }
+    #
+    $r->print('</table>');
+    #
+    # Debugging code (be sure to uncomment errorlog code in safe space):
+    #
+    # $r->print("\n<pre>");
+    # $r->print(&geterrorlog($self));
+    # $r->print("\n</pre>");
+    return 1;
+}
+
+############################################
+##         csv output routines            ##
+############################################
+sub outsheet_csv   {
+    my $self = shift;
+    my ($r) = @_;
+    my $csvdata = '';
+    my @Values;
+    ####################################
+    # Prepare to output rows
+    ####################################
+    my @Rows = $self->sort_indicies();
+    #
+    # Loop through the rows and output them one at a time
+    my $rows_output=0;
+    foreach my $rownum (@Rows) {
+        my ($rowlabel,@rowdata) = $self->get_row($rownum);
+        next if ($rowlabel =~ /^\s*$/);
+        push (@Values,$self->format_csv_rowlabel($rowlabel));
+        foreach my $cell (@rowdata) {
+            push (@Values,'"'.$cell->{'value'}.'"');
+        }
+        $csvdata.= join(',',@Values)."\n";
+        @Values = ();
+    }
+    #
+    # Write the CSV data to a file and serve up a link
+    #
+    my $filename = '/prtspool/'.
+        $ENV{'user.name'}.'_'.$ENV{'user.domain'}.'_'.
+        time.'_'.rand(1000000000).'.csv';
+    my $file;
+    unless ($file = Apache::File->new('>'.'/home/httpd'.$filename)) {
+        $r->log_error("Couldn't open $filename for output $!");
+        $r->print("Problems occured in writing the csv file.  ".
+                  "This error has been logged.  ".
+                  "Please alert your LON-CAPA administrator.");
+        $r->print("<pre>\n".$csvdata."</pre>\n");
+        return 0;
+    }
+    print $file $csvdata;
+    close($file);
+    $r->print('<br /><br />'.
+              '<a href="'.$filename.'">Your CSV spreadsheet.</a>'."\n");
+    #
+    return 1;
+}
+
+############################################
+##        Excel output routines           ##
+############################################
+sub outsheet_recursive_excel {
+    my $self = shift;
+    my ($r) = @_;
+    my $c = $r->connection;
+    return undef if ($self->{'type'} ne 'classcalc');
+    my ($workbook,$filename) = $self->create_excel_spreadsheet($r);
+    return undef if (! defined($workbook));
+    #
+    # Create main worksheet
+    my $main_worksheet = $workbook->addworksheet('main');
+    #
+    # Figure out who the students are
+    my %f=$self->formulas();
+    my $count = 0;
+    $r->print(<<END);
+<p>
+Compiling Excel Workbook with a worksheet for each student.
+</p><p>
+This operation may take longer than a complete recalculation of the
+spreadsheet. 
+</p><p>
+To abort this operation, hit the stop button on your browser.
+</p><p>
+A link to the spreadsheet will be available at the end of this process.
+</p>
+<p>
+END
+    $r->rflush();
+    my $starttime = time;
+    foreach my $rownum ($self->sort_indicies()) {
+        $count++;
+        my ($sname,$sdom) = split(':',$f{'A'.$rownum});
+        my $student_excel_worksheet=$workbook->addworksheet($sname.'@'.$sdom);
+        # Create a new spreadsheet
+        my $studentsheet = &Apache::lonspreadsheet::Spreadsheet->new
+                                   ($sname,$sdom,'studentcalc',undef);
+        # Read in the spreadsheet definition
+        $studentsheet->update_student_sheet($r,$c);
+        # Stuff the sheet into excel
+        $studentsheet->export_sheet_as_excel($student_excel_worksheet);
+        my $totaltime = int((time - $starttime) / $count * $self->{'maxrow'});
+        my $timeleft = int((time - $starttime) / $count * ($self->{'maxrow'} - $count));
+        if ($count % 5 == 0) {
+            $r->print($count.' students completed.'.
+                      '  Time remaining: '.$timeleft.' sec. '.
+                      '  Estimated total time: '.$totaltime." sec <br />\n");
+            $r->rflush();
+        }
+        if(defined($c) && ($c->aborted())) {
+            last;
+        }
+    }
+    #
+    if(! $c->aborted() ) {
+        $r->print('All students spreadsheets completed!<br />');
+        $r->rflush();
+        #
+        # &export_sheet_as_excel fills $worksheet with the data from $sheet
+        $self->export_sheet_as_excel($main_worksheet);
+        #
+        $workbook->close();
+        # Okay, the spreadsheet is taken care of, so give the user a link.
+        $r->print('<br /><br />'.
+                  '<a href="'.$filename.'">Your Excel spreadsheet.</a>'."\n");
+    } else {
+        $workbook->close();  # Not sure how necessary this is.
+        #unlink('/home/httpd'.$filename); # No need to keep this around?
+    }
+    return 1;
 }
 
-# --------------------------------------------------------------- Get user home
-
-sub getuhome {
-    my $safeeval=shift;
-    return $safeeval->reval('$uhome');
+sub outsheet_excel {
+    my $self = shift;
+    my ($r) = @_;
+    my ($workbook,$filename) = $self->create_excel_spreadsheet($r);
+    return undef if (! defined($workbook));
+    my $sheetname;
+    if ($self->{'type'} eq 'classcalc') {
+        $sheetname = 'Main';
+    } elsif ($self->{'type'} eq 'studentcalc') {
+        $sheetname = $self->{'uname'}.'@'.$self->{'udom'};
+    } elsif ($self->{'type'} eq 'assesscalc') {
+        $sheetname = $self->{'uname'}.'@'.$self->{'udom'}.' assessment';
+    }
+    my $worksheet = $workbook->addworksheet($sheetname);
+    #
+    # &export_sheet_as_excel fills $worksheet with the data from $sheet
+    $self->export_sheet_as_excel($worksheet);
+    #
+    $workbook->close();
+    # Okay, the spreadsheet is taken care of, so give the user a link.
+    $r->print('<br /><br />'.
+              '<a href="'.$filename.'">Your Excel spreadsheet.</a>'."\n");
+    return 1;
+}
+
+sub create_excel_spreadsheet {
+    my $self = shift;
+    my ($r) = @_;
+    my $filename = '/prtspool/'.
+        $ENV{'user.name'}.'_'.$ENV{'user.domain'}.'_'.
+        time.'_'.rand(1000000000).'.xls';
+    my $workbook  = Spreadsheet::WriteExcel->new('/home/httpd'.$filename);
+    if (! defined($workbook)) {
+        $r->log_error("Error creating excel spreadsheet $filename: $!");
+        $r->print("Problems creating new Excel file.  ".
+                  "This error has been logged.  ".
+                  "Please alert your LON-CAPA administrator");
+        return undef;
+    }
+    #
+    # The excel spreadsheet stores temporary data in files, then put them
+    # together.  If needed we should be able to disable this (memory only).
+    # The temporary directory must be specified before calling 'addworksheet'.
+    # File::Temp is used to determine the temporary directory.
+    $workbook->set_tempdir('/home/httpd/perl/tmp');
+    #
+    # Determine the name to give the worksheet
+    return ($workbook,$filename);
+}
+
+sub export_sheet_as_excel {
+    my $self = shift;
+    my $worksheet = shift;
+    #
+    my $rows_output = 0;
+    my $cols_output = 0;
+    ####################################
+    #    Write an identifying row      #
+    ####################################
+    my @Headerinfo = ($self->{'coursedesc'});
+    my $title = $self->gettitle();
+    $cols_output = 0;    
+    if (defined($title)) {
+        $worksheet->write($rows_output++,$cols_output++,$title);
+    }
+    ####################################
+    #   Write the summary/export row   #
+    ####################################
+    my ($rowlabel,@rowdata) = &get_row($self,'0');
+    my $label = &format_excel_rowlabel($self,$rowlabel);
+    $cols_output = 0;
+    $worksheet->write($rows_output,$cols_output++,$label);
+    foreach my $cell (@rowdata) {
+        $worksheet->write($rows_output,$cols_output++,$cell->{'value'});
+    }
+    $rows_output+= 2;   # Skip a row, just for fun
+    ####################################
+    # Prepare to output rows
+    ####################################
+    my @Rows = &sort_indicies($self);
+    #
+    # Loop through the rows and output them one at a time
+    foreach my $rownum (@Rows) {
+        my ($rowlabel,@rowdata) = &get_row($self,$rownum);
+        next if ($rowlabel =~ /^[\s]*$/);
+        $cols_output = 0;
+        my $label = &format_excel_rowlabel($self,$rowlabel);
+        if ( ! $ENV{'form.showall'} &&
+             $self->{'type'} =~ /^(studentcalc|classcalc)$/) {
+            my $row_is_empty = 1;
+            foreach my $cell (@rowdata) {
+                if ($cell->{'value'} !~  /^\s*$/) {
+                    $row_is_empty = 0;
+                    last;
+                }
+            }
+            next if ($row_is_empty);
+        }
+        $worksheet->write($rows_output,$cols_output++,$rownum);
+        $worksheet->write($rows_output,$cols_output++,$label);
+        if (ref($label)) {
+            $cols_output = (scalar(@$label));
+        }
+        foreach my $cell (@rowdata) {
+            $worksheet->write($rows_output,$cols_output++,$cell->{'value'});
+        }
+        $rows_output++;
+    }
+    return;
 }
 
-# -------------------------------------------------------------------- Get symb
-
-sub getusymb {
-    my $safeeval=shift;
-    return $safeeval->reval('$usymb');
+############################################
+##          XML output routines           ##
+############################################
+sub outsheet_xml   {
+    my $self = shift;
+    my ($r) = @_;
+    ## Someday XML
+    ## Will be rendered for the user
+    ## But not on this day
 }
 
-# ------------------------------------------------------------- Export of A-row
-
-sub exportdata {
-    my $safeeval=shift;
-    return $safeeval->reval('&exportrowa()');
+##
+## Outsheet - calls other outsheet_* functions
+##
+sub outsheet {
+    my $self = shift;
+    my ($r)=@_;
+    if (! exists($ENV{'form.output'})) {
+        $ENV{'form.output'} = 'HTML';
+    }
+    if (lc($ENV{'form.output'}) eq 'csv') {
+        $self->outsheet_csv($r);
+    } elsif (lc($ENV{'form.output'}) eq 'excel') {
+        $self->outsheet_excel($r);
+    } elsif (lc($ENV{'form.output'}) eq 'recursive excel') {
+        $self->outsheet_recursive_excel($r);
+#    } elsif (lc($ENV{'form.output'}) eq 'xml' ) {
+#        $self->outsheet_xml($r);
+    } else {
+        $self->outsheet_html($r);
+    }
 }
 
-# ========================================================== End of Spreadsheet
-# =============================================================================
-
 #
-# Procedures for screen output
-#
-# --------------------------------------------- Produce output row n from sheet
-
-sub rown {
-    my ($safeeval,$n)=@_;
-    my $defaultbg;
-    my $rowdata='';
-    unless ($n eq '-') {
-       $defaultbg=((($n-1)/5)==int(($n-1)/5))?'#E0E0':'#FFFF';
-    } else {
-       $defaultbg='#E0FF';
-    }
-    if ((($n-1)/25)==int(($n-1)/25)) {
-        my $what='Student';
-        if (&gettype($safeeval) eq 'assesscalc') {
-	    $what='Item';
-	} elsif (&gettype($safeeval) eq 'studentcalc') {
-            $what='Assessment';
-        }
-	$rowdata.="</table>\n<br><table border=2>".
-        '<tr><td>&nbsp;<td>'.$what.'</td>';
-        map {
-           $rowdata.='<td>'.$_.'</td>';
-        } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-           'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-           'a','b','c','d','e','f','g','h','i','j','k','l','m',
-           'n','o','p','q','r','s','t','u','v','w','x','y','z');
-        $rowdata.='</tr>';
-    }
-    $rowdata.="\n<tr><td><b><font size=+1>$n</font></b></td>";
-    my $showf=0;
-    my $proc;
-    my $maxred;
-    if (&gettype($safeeval) eq 'assesscalc') {
-        $proc='&outrowassess';
-        $maxred=1;
-    } else {
-        $proc='&outrow';
-        $maxred=26;
-    }
-    if ($n eq '-') { $proc='&templaterow'; $n=-1; }
-    map {
-       my $bgcolor=$defaultbg.((($showf-1)/5==int(($showf-1)/5))?'99':'DD');
-       my ($fm,$vl)=split(/\_\_\_eq\_\_\_/,$_);
-       if ($showf==0) { $vl=$_; }
-       if ($showf<=$maxred) { $bgcolor='#FFDDDD'; }
-       if (($n==0) && ($showf<=26)) { $bgcolor='#CCCCFF'; } 
-       if (($showf>$maxred) || ((!$n) && ($showf>0))) {
-	   if ($vl eq '') {
-	       $vl='<font size=+2 color='.$bgcolor.'>&#35;</font>';
-           }
-           $rowdata.=
-       '<td bgcolor='.$bgcolor.'><a href="javascript:celledit('.$fm.');">'.$vl.
-	       '</a></td>';
-       } else {
-           $rowdata.='<td bgcolor='.$bgcolor.'>&nbsp;'.$vl.'&nbsp;</td>';
-       }
-       $showf++;
-    } $safeeval->reval($proc.'('.$n.')');
-    return $rowdata.'</tr>';
+# othersheets: Returns the list of other spreadsheets available 
+#
+sub othersheets {
+    my $self = shift;
+    my ($stype)=@_;
+    $stype = $self->{'type'} if (! defined($stype));
+    #
+    my $cnum  = $self->{'cnum'};
+    my $cdom  = $self->{'cdom'};
+    my $chome = $self->{'chome'};
+    #
+    my @alternatives=();
+    my %results=&Apache::lonnet::dump($stype.'_spreadsheets',$cdom,$cnum);
+    my ($tmp) = keys(%results);
+    unless ($tmp =~ /^(con_lost|error|no_such_host)/i) {
+        @alternatives = sort (keys(%results));
+    }
+    return @alternatives; 
 }
 
-# ------------------------------------------------------------- Print out sheet
-
-sub outsheet {
-    my ($r,$safeeval)=@_;
-    my $maxred;
-    my $realm;
-    if (&gettype($safeeval) eq 'assesscalc') {
-        $maxred=1;
-        $realm='Assessment';
-    } elsif (&gettype($safeeval) eq 'studentcalc') {
-        $maxred=26;
-        $realm='User';
-    } else {
-        $maxred=26;
-        $realm='Course';
-    }
-    my $maxyellow=52-$maxred;
-    my $tabledata=
-        '<table border=2><tr><th colspan=2 rowspan=2><font size=+2>'.
-                  $realm.'</font></th>'.
-                  '<td bgcolor=#FFDDDD colspan='.$maxred.
-                  '><b><font size=+1>Import</font></b></td>'.
-                  '<td colspan='.$maxyellow.
-		  '><b><font size=+1>Calculations</font></b></td></tr><tr>';
-    my $showf=0;
-    map {
-        $showf++;
-        if ($showf<=$maxred) { 
-           $tabledata.='<td bgcolor="#FFDDDD">'; 
-        } else {
-           $tabledata.='<td>';
+#
+# Parse a spreadsheet
+# 
+sub parse_sheet {
+    # $sheetxml is a scalar reference or a scalar
+    my ($sheetxml) = @_;
+    if (! ref($sheetxml)) {
+        my $tmp = $sheetxml;
+        $sheetxml = \$tmp;
+    }
+    my %f;
+    my $parser=HTML::TokeParser->new($sheetxml);
+    my $token;
+    while ($token=$parser->get_token) {
+        if ($token->[0] eq 'S') {
+            if ($token->[1] eq 'field') {
+                $f{$token->[2]->{'col'}.$token->[2]->{'row'}}=
+                    $parser->get_text('/field');
+            }
+            if ($token->[1] eq 'template') {
+                $f{'template_'.$token->[2]->{'col'}}=
+                    $parser->get_text('/template');
+            }
         }
-        $tabledata.="<b><font size=+1>$_</font></b></td>";
-    } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-       'N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
-       'a','b','c','d','e','f','g','h','i','j','k','l','m',
-       'n','o','p','q','r','s','t','u','v','w','x','y','z');
-    $tabledata.='</tr>';
-    my $row;
-    my $maxrow=&getmaxrow($safeeval);
-    $tabledata.=&rown($safeeval,'-');
-    $r->print($tabledata);
-    for ($row=0;$row<=$maxrow;$row++) {
-        $r->print(&rown($safeeval,$row));
     }
-    $r->print('</table>');
+    return \%f;
 }
 
-#
-# -------------------------------------- Read spreadsheet formulas for a course
-#
-
 sub readsheet {
-  my ($safeeval,$fn)=@_;
-  my $stype=&gettype($safeeval);
-  my $cnum=&getcnum($safeeval);
-  my $cdom=&getcdom($safeeval);
-  my $chome=&getchome($safeeval);
-
-# --------- There is no filename. Look for defaults in course and global, cache
-
-  unless($fn) {
-      unless ($fn=$defaultsheets{$cnum.'_'.$cdom.'_'.$stype}) {
-         $fn=&Apache::lonnet::reply('get:'.$cdom.':'.$cnum.
-                                    ':environment:spreadsheet_default_'.$stype,
-                                    $chome);
-         unless (($fn) && ($fn!~/^error\:/)) {
-	     $fn='default_'.$stype;
-         }
-         $defaultsheets{$cnum.'_'.$cdom.'_'.$stype}=$fn; 
-      }
-  }
-
-# ---------------------------------------------------------- fn now has a value
-
-  &setfilename($safeeval,$fn);
-
-# ------------------------------------------------------ see if sheet is cached
-  my $fstring='';
-  if ($fstring=$spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn}) {
-      &setformulas($safeeval,split(/\_\_\_\;\_\_\_/,$fstring));
-  } else {
-
-# ---------------------------------------------------- Not cached, need to read
-
-     my %f=();
-
-     if ($fn=~/^default\_/) {
-	my $sheetxml='';
-       {
-         my $fh;
-         if ($fh=Apache::File->new($includedir.
-                         '/default.'.&gettype($safeeval))) {
-               $sheetxml=join('',<$fh>);
-          }
-       }
-        my $parser=HTML::TokeParser->new(\$sheetxml);
-        my $token;
-        while ($token=$parser->get_token) {
-          if ($token->[0] eq 'S') {
- 	     if ($token->[1] eq 'field') {
- 		 $f{$token->[2]->{'col'}.$token->[2]->{'row'}}=
- 		     $parser->get_text('/field');
- 	     }
-             if ($token->[1] eq 'template') {
-                 $f{'template_'.$token->[2]->{'col'}}=
-                     $parser->get_text('/template');
-             }
-          }
-        }
-      } else {
-          my $sheet='';
-          my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum.':'.$fn,
-                                         $chome);
-          unless ($reply=~/^error\:/) {
-             $sheet=$reply;
-	  }
-          map {
-             my ($name,$value)=split(/\=/,$_);
-             $f{&Apache::lonnet::unescape($name)}=
-	        &Apache::lonnet::unescape($value);
-          } split(/\&/,$sheet);
-       }
-# --------------------------------------------------------------- Cache and set
-       $spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn}=join('___;___',%f);  
-       &setformulas($safeeval,%f);
+    my $self = shift;
+    my ($fn)=@_;
+    #
+    my $stype = $self->{'type'};
+    my $cnum  = $self->{'cnum'};
+    my $cdom  = $self->{'cdom'};
+    my $chome = $self->{'chome'};
+    #
+    if (! defined($fn)) {
+        # There is no filename. Look for defaults in course and global, cache
+        unless ($fn=$defaultsheets{$cnum.'_'.$cdom.'_'.$stype}) {
+            my %tmphash = &Apache::lonnet::get('environment',
+                                               ['spreadsheet_default_'.$stype],
+                                               $cdom,$cnum);
+            my ($tmp) = keys(%tmphash);
+            if ($tmp =~ /^(con_lost|error|no_such_host)/i) {
+                $fn = 'default_'.$stype;
+            } else {
+                $fn = $tmphash{'spreadsheet_default_'.$stype};
+            } 
+            unless (($fn) && ($fn!~/^error\:/)) {
+                $fn='default_'.$stype;
+            }
+            $defaultsheets{$cnum.'_'.$cdom.'_'.$stype}=$fn; 
+        }
+    }
+    # $fn now has a value
+    $self->{'filename'} = $fn;
+    # see if sheet is cached
+    if (exists($spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn})) {
+        
+        my %tmp = split(/___;___/,
+                        $spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn});
+        $self->formulas(\%tmp);
+    } else {
+        # Not cached, need to read
+        my %f=();
+        if ($fn=~/^default\_/) {
+            my $sheetxml='';
+            my $fh;
+            my $dfn=$fn;
+            $dfn=~s/\_/\./g;
+            if ($fh=Apache::File->new($includedir.'/'.$dfn)) {
+                $sheetxml=join('',<$fh>);
+            } else {
+                # $sheetxml='<field row="0" col="A">"Error"</field>';
+                $sheetxml='<field row="0" col="A"></field>';
+            }
+            %f=%{&parse_sheet(\$sheetxml)};
+        } elsif($fn=~/\/*\.spreadsheet$/) {
+            my $sheetxml=&Apache::lonnet::getfile
+                (&Apache::lonnet::filelocation('',$fn));
+            if ($sheetxml == -1) {
+                $sheetxml='<field row="0" col="A">"Error loading spreadsheet '
+                    .$fn.'"</field>';
+            }
+            %f=%{&parse_sheet(\$sheetxml)};
+        } else {
+            my %tmphash = &Apache::lonnet::dump($fn,$cdom,$cnum);
+            my ($tmp) = keys(%tmphash);
+            if ($tmp !~ /^(con_lost|error|no_such_host)/i) {
+                foreach (keys(%tmphash)) {
+                    $f{$_}=$tmphash{$_};
+                }
+            } else {
+                # Unable to grab the specified spreadsheet,
+                # so we get the default ones instead.
+                $fn = 'default_'.$stype;
+                $self->{'filename'} = $fn;
+                my $dfn = $fn;
+                $dfn =~ s/\_/\./g;
+                my $sheetxml;
+                if (my $fh=Apache::File->new($includedir.'/'.$dfn)) {
+                    $sheetxml = join('',<$fh>);
+                } else {
+                    $sheetxml='<field row="0" col="A">'.
+                        '"Unable to load spreadsheet"</field>';
+                }
+                %f=%{&parse_sheet(\$sheetxml)};
+            }
+        }
+        # Cache and set
+        $spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn}=join('___;___',%f);  
+        $self->formulas(\%f);
     }
-}
-
-# -------------------------------------------------------- Make new spreadsheet
-
-sub makenewsheet {
-    my ($uname,$udom,$stype,$usymb)=@_;
-    my $safeeval=initsheet();
-    $safeeval->reval(
-       '$uname="'.$uname.
-      '";$udom="'.$udom.
-      '";$uhome="'.&Apache::lonnet::homeserver($uname,$udom).
-      '";$sheettype="'.$stype.
-      '";$usymb="'.$usymb.
-      '";$csec="'.&Apache::lonnet::usection($udom,$uname,
-                                            $ENV{'request.course.id'}).
-      '";$cid="'.$ENV{'request.course.id'}.
-      '";$cfn="'.$ENV{'request.course.fn'}.
-      '";$cnum="'.$ENV{'course.'.$ENV{'request.course.id'}.'.num'}.
-      '";$cdom="'.$ENV{'course.'.$ENV{'request.course.id'}.'.domain'}.
-      '";$chome="'.$ENV{'course.'.$ENV{'request.course.id'}.'.home'}.'";');
-    return $safeeval;
 }
 
 # ------------------------------------------------------------ Save spreadsheet
-
 sub writesheet {
-  my ($safeeval,$makedef)=@_;
-  my $cid=&getcid($safeeval);
-  if (&Apache::lonnet::allowed('opa',$cid)) {
-    my %f=&getformulas($safeeval);
-    my $stype=&gettype($safeeval);
-    my $cnum=&getcnum($safeeval);
-    my $cdom=&getcdom($safeeval);
-    my $chome=&getchome($safeeval);
-    my $fn=&getfilename($safeeval);
-
-# ------------------------------------------------------------- Cache new sheet
-    $spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn}=join('___;___',%f);    
-# ----------------------------------------------------------------- Write sheet
-    my $sheetdata='';
-    map {
-       $sheetdata.=&Apache::lonnet::escape($_).'='.
-	   &Apache::lonnet::escape($f{$_}).'&';
-    } keys %f;
-    $sheetdata=~s/\&$//;
-    my $reply=&Apache::lonnet::reply('put:'.$cdom.':'.$cnum.':'.$fn.':'.
-              $sheetdata,$chome);
-    if ($reply eq 'ok') {
-          $reply=&Apache::lonnet::reply('put:'.$cdom.':'.$cnum.':'.
-              $stype.'_spreadsheets:'.
-              &Apache::lonnet::escape($fn).'='.$ENV{'user.name'},
-              $chome);
-          if ($reply eq 'ok') {
-              if ($makedef) { 
-                return &Apache::lonnet::reply('put:'.$cdom.':'.$cnum.
-                                ':environment:spreadsheet_default_'.$stype.'='.
-                                &Apache::lonnet::escape($fn),
-                                $chome);
-	      } else {
-		  return $reply;
-    	      }
-	   } else {
-	       return $reply;
-           }
-      } else {
-	  return $reply;
-      }
-  }
-  return 'unauthorized';
+    my $self = shift;
+    my ($makedef)=@_;
+    my $cid=$self->{'cid'};
+    if (&Apache::lonnet::allowed('opa',$cid)) {
+        my %f=$self->formulas();
+        my $stype= $self->{'type'};
+        my $cnum = $self->{'cnum'};
+        my $cdom = $self->{'cdom'};
+        my $chome= $self->{'chome'};
+        my $fn   = $self->{'filename'};
+        # Cache new sheet
+        $spreadsheets{$cnum.'_'.$cdom.'_'.$stype.'_'.$fn}=join('___;___',%f);
+        # Write sheet
+        foreach (keys(%f)) {
+            delete($f{$_}) if ($f{$_} eq 'import');
+        }
+        my $reply = &Apache::lonnet::put($fn,\%f,$cdom,$cnum);
+        if ($reply eq 'ok') {
+            $reply = &Apache::lonnet::put($stype.'_spreadsheets',
+                            {$fn => $ENV{'user.name'}.'@'.$ENV{'user.domain'}},
+                                          $cdom,$cnum);
+            if ($reply eq 'ok') {
+                if ($makedef) { 
+                    $reply = &Apache::lonnet::put('environment',
+                                    {'spreadsheet_default_'.$stype => $fn },
+                                                  $cdom,$cnum);
+                    if ($reply eq 'ok' && 
+                        ($self->{'type'} eq 'studentcalc' ||
+                         $self->{'type'} eq 'assesscalc')) {
+                        # Expire the spreadsheets of the other students.
+                        &Apache::lonnet::expirespread('','','studentcalc','');
+                    }
+                    return $reply;
+                } 
+                return $reply;
+            } 
+            return $reply;
+        } 
+        return $reply;
+    }
+    return 'unauthorized';
 }
 
 # ----------------------------------------------- Make a temp copy of the sheet
 # "Modified workcopy" - interactive only
 #
-
 sub tmpwrite {
-    my $safeeval=shift;
+    my $self = shift;
     my $fn=$ENV{'user.name'}.'_'.
-           $ENV{'user.domain'}.'_spreadsheet_'.&getusymb($safeeval).'_'.
-           &getfilename($safeeval);
+        $ENV{'user.domain'}.'_spreadsheet_'.$self->{'usymb'}.'_'.
+           $self->{'filename'};
     $fn=~s/\W/\_/g;
     $fn=$tmpdir.$fn.'.tmp';
     my $fh;
     if ($fh=Apache::File->new('>'.$fn)) {
-	print $fh join("\n",&getformulas($safeeval));
+        my %f = $self->formulas();
+        while( my ($cell,$formula) = each(%f)) {
+            print $fh &Apache::lonnet::escape($cell)."=".&Apache::lonnet::escape($formula)."\n";
+        }
     }
 }
 
-# ---------------------------------------------------------- Read the temp copy
 
+# ---------------------------------------------------------- Read the temp copy
 sub tmpread {
-    my ($safeeval,$nfield,$nform)=@_;
+    my $self = shift;
+    my ($nfield,$nform)=@_;
     my $fn=$ENV{'user.name'}.'_'.
-           $ENV{'user.domain'}.'_spreadsheet_'.&getusymb($safeeval).'_'.
-           &getfilename($safeeval);
+           $ENV{'user.domain'}.'_spreadsheet_'.$self->{'usymb'}.'_'.
+           $self->{'filename'};
     $fn=~s/\W/\_/g;
     $fn=$tmpdir.$fn.'.tmp';
     my $fh;
     my %fo=();
+    my $countrows=0;
     if ($fh=Apache::File->new($fn)) {
-        my $name;
-        while ($name=<$fh>) {
-	    chomp($name);
-            my $value=<$fh>;
-            chomp($value);
-            $fo{$name}=$value;
+        while (<$fh>) {
+	    chomp;
+            my ($cell,$formula) = split(/=/);
+            $cell    = &Apache::lonnet::unescape($cell);
+            $formula = &Apache::lonnet::unescape($formula);
+            $fo{$cell} = $formula;
         }
     }
-    if ($nfield) { $fo{$nfield}=$nform; }
-    &setformulas($safeeval,%fo);
+    if ($nform eq 'changesheet') {
+        $fo{'A'.$nfield}=(split(/__&&&\__/,$fo{'A'.$nfield}))[0];
+        unless ($ENV{'form.sel_'.$nfield} eq 'Default') {
+	    $fo{'A'.$nfield}.='__&&&__'.$ENV{'form.sel_'.$nfield};
+        }
+    } else {
+       if ($nfield) { $fo{$nfield}=$nform; }
+    }
+    $self->formulas(\%fo);
 }
 
-# ================================================================== Parameters
-# -------------------------------------------- Figure out a cascading parameter
-#
-# For this function to work
-#
-# * parmhash needs to be tied
-# * courseopt and useropt need to be initialized for this user and course
-#
-
-sub parmval {
-    my ($what,$safeeval)=@_;
-    my $cid=&getcid($safeeval);
-    my $csec=&getcsec($safeeval);
-    my $uname=&getuname($safeeval);
-    my $udom=&getudom($safeeval);
-    my $symb=&getusymb($safeeval);
-
-    unless ($symb) { return ''; }
-    my $result='';
-
-    my ($mapname,$id,$fn)=split(/\_\_\_/,$symb);
-# ----------------------------------------------------- Cascading lookup scheme
-       my $rwhat=$what;
-       $what=~s/^parameter\_//;
-       $what=~s/\_/\./;
-
-       my $symbparm=$symb.'.'.$what;
-       my $mapparm=$mapname.'___(all).'.$what;
-       my $usercourseprefix=$uname.'_'.$udom.'_'.$cid;
-
-       my $seclevel=
-            $usercourseprefix.'.['.
-		$csec.'].'.$what;
-       my $seclevelr=
-            $usercourseprefix.'.['.
-		$csec.'].'.$symbparm;
-       my $seclevelm=
-            $usercourseprefix.'.['.
-		$csec.'].'.$mapparm;
-
-       my $courselevel=
-            $usercourseprefix.'.'.$what;
-       my $courselevelr=
-            $usercourseprefix.'.'.$symbparm;
-       my $courselevelm=
-            $usercourseprefix.'.'.$mapparm;
-
-# ---------------------------------------------------------- fourth, check user
-      
-      if ($uname) { 
-
-       if ($useropt{$courselevelr}) { return $useropt{$courselevelr}; }
-
-       if ($useropt{$courselevelm}) { return $useropt{$courselevelm}; }
-
-       if ($useropt{$courselevel}) { return $useropt{$courselevel}; }
-
-      }
-
-# --------------------------------------------------------- third, check course
-     
-       if ($csec) {
- 
-        if ($courseopt{$seclevelr}) { return $courseopt{$seclevelr}; }
-
-        if ($courseopt{$seclevelm}) { return $courseopt{$seclevelm}; }  
-
-        if ($courseopt{$seclevel}) { return $courseopt{$seclevel}; }
-  
-      }
-
-       if ($courseopt{$courselevelr}) { return $courseopt{$courselevelr}; }
-
-       if ($courseopt{$courselevelm}) { return $courseopt{$courselevelm}; }
-
-       if ($courseopt{$courselevel}) { return $courseopt{$courselevel}; }
-
-# ----------------------------------------------------- second, check map parms
-
-       my $thisparm=$parmhash{$symbparm};
-       if ($thisparm) { return $thisparm; }
+##################################################################
+##                  Row label formatting routines               ##
+##################################################################
+sub format_html_rowlabel {
+    my $self = shift;
+    my $rowlabel = shift;
+    return '' if ($rowlabel eq '');
+    my ($type,$labeldata) = split(':',$rowlabel,2);
+    my $result = '';
+    if ($type eq 'symb') {
+        my ($symb,$mapid,$resid,$title,$ufn) = split(':',$labeldata);
+        $ufn   = 'default' if (!defined($ufn) || $ufn eq '');
+        $ufn   = &Apache::lonnet::unescape($ufn);
+        $symb  = &Apache::lonnet::unescape($symb);
+        $title = &Apache::lonnet::unescape($title);
+        $result = '<a href="/adm/assesscalc?usymb='.$symb.
+            '&uname='.$self->{'uname'}.'&udom='.$self->{'udom'}.
+                '&ufn='.$ufn.
+                    '&mapid='.$mapid.'&resid='.$resid.'">'.$title.'</a>';
+    } elsif ($type eq 'student') {
+        my ($sname,$sdom,$fullname,$section,$id) = split(':',$labeldata);
+        if ($fullname =~ /^\s*$/) {
+            $fullname = $sname.'@'.$sdom;
+        }
+        $result ='<a href="/adm/studentcalc?uname='.$sname.
+            '&udom='.$sdom.'">';
+        $result.=$section.'&nbsp;'.$id."&nbsp;".$fullname.'</a>';
+    } elsif ($type eq 'parameter') {
+        $result = $labeldata;
+    } else {
+        $result = '<b><font size=+1>'.$rowlabel.'</font></b>';
+    }
+    return $result;
+}
 
-# -------------------------------------------------------- first, check default
+sub format_csv_rowlabel {
+    my $self = shift;
+    my $rowlabel = shift;
+    return '' if ($rowlabel eq '');
+    my ($type,$labeldata) = split(':',$rowlabel,2);
+    my $result = '';
+    if ($type eq 'symb') {
+        my ($symb,$mapid,$resid,$title,$ufn) = split(':',$labeldata);
+        $ufn   = &Apache::lonnet::unescape($ufn);
+        $symb  = &Apache::lonnet::unescape($symb);
+        $title = &Apache::lonnet::unescape($title);
+        $result = $title;
+    } elsif ($type eq 'student') {
+        my ($sname,$sdom,$fullname,$section,$id) = split(':',$labeldata);
+        $result = join('","',($sname,$sdom,$fullname,$section,$id));
+    } elsif ($type eq 'parameter') {
+        $labeldata =~ s/<br>/ /g;
+        $result = $labeldata;
+    } else {
+        $result = $rowlabel;
+    }
+    return '"'.$result.'"';
+}
 
-       return &Apache::lonnet::metadata($fn,$rwhat.'.default');
-        
+sub format_excel_rowlabel {
+    my $self = shift;
+    my $rowlabel = shift;
+    return '' if ($rowlabel eq '');
+    my ($type,$labeldata) = split(':',$rowlabel,2);
+    my $result = '';
+    if ($type eq 'symb') {
+        my ($symb,$mapid,$resid,$title,$ufn) = split(':',$labeldata);
+        $ufn   = &Apache::lonnet::unescape($ufn);
+        $symb  = &Apache::lonnet::unescape($symb);
+        $title = &Apache::lonnet::unescape($title);
+        $result = $title;
+    } elsif ($type eq 'student') {
+        my ($sname,$sdom,$fullname,$section,$id) = split(':',$labeldata);
+        $section = '' if (! defined($section));
+        $id      = '' if (! defined($id));
+        my @Data = ($sname,$sdom,$fullname,$section,$id);
+        $result = \@Data;
+    } elsif ($type eq 'parameter') {
+        $labeldata =~ s/<br>/ /g;
+        $result = $labeldata;
+    } else {
+        $result = $rowlabel;
+    }
+    return $result;
 }
 
 # ---------------------------------------------- Update rows for course listing
-
 sub updateclasssheet {
-    my $safeeval=shift;
-    my $cnum=&getcnum($safeeval);
-    my $cdom=&getcdom($safeeval);
-    my $cid=&getcid($safeeval);
-    my $chome=&getchome($safeeval);
-
-# ---------------------------------------------- Read class list and row labels
-
-    my $classlst=&Apache::lonnet::reply
-                                 ('dump:'.$cdom.':'.$cnum.':classlist',$chome);
+    my $self = shift;
+    my $cnum  =$self->{'cnum'};
+    my $cdom  =$self->{'cdom'};
+    my $cid   =$self->{'cid'};
+    my $chome =$self->{'chome'};
+    #
+    %Section = ();
+    #
+    # Read class list and row labels
+    my $classlist = &Apache::loncoursedata::get_classlist();
+    if (! defined($classlist)) {
+        return 'Could not access course classlist';
+    } 
+    #
     my %currentlist=();
-    my $now=time;
-    unless ($classlst=~/^error\:/) {
-        map {
-            my ($name,$value)=split(/\=/,$_);
-            my ($end,$start)=split(/\:/,&Apache::lonnet::unescape($value));
-            my $active=1;
-            if (($end) && ($now>$end)) { $active=0; }
-            if ($active) {
-                my $rowlabel='';
-                $name=&Apache::lonnet::unescape($name);
-                my ($sname,$sdom)=split(/\:/,$name);
-                my $ssec=&Apache::lonnet::usection($sdom,$sname,$cid);
-                if ($ssec==-1) {
-                    $rowlabel='<font color=red>Data not available: '.$name.
-			      '</font>';
-                } else {
-                    my %reply=&Apache::lonnet::idrget($sdom,$sname);
-                    my $reply=&Apache::lonnet::reply('get:'.$sdom.':'.$sname.
-		      ':environment:firstname&middlename&lastname&generation',
-                      &Apache::lonnet::homeserver($sname,$sdom));
-                    $rowlabel=$ssec.'&nbsp;'.$reply{$sname}.'<br>';
-                    map {
-                        $rowlabel.=&Apache::lonnet::unescape($_).' ';
-                    } split(/\&/,$reply);
-                }
-		$currentlist{&Apache::lonnet::unescape($name)}=$rowlabel;
-            }
-        } split(/\&/,$classlst);
-#
-# -------------------- Find discrepancies between the course row table and this
-#
-        my %f=&getformulas($safeeval);
-        my $changed=0;
-
-        my $maxrow=0;
-        my %existing=();
-
-# ----------------------------------------------------------- Now obsolete rows
-	map {
-	    if ($_=~/^A(\d+)/) {
-                $maxrow=($1>$maxrow)?$1:$maxrow;
-                $existing{$f{$_}}=1;
-		unless ((defined($currentlist{$f{$_}})) || (!$1)) {
-		   $f{$_}='!!! Obsolete';
-                   $changed=1;
-                }
-            }
-        } keys %f;
+    foreach my $student (keys(%$classlist)) {
+        my ($studentDomain,$studentName,$end,$start,$id,$studentSection,
+            $fullname,$status)   =   @{$classlist->{$student}};
+        $Section{$studentName.':'.$studentDomain} = $studentSection;
+        if ($ENV{'form.Status'} eq $status || $ENV{'form.Status'} eq 'Any') {
+            $currentlist{$student}=join(':',('student',$studentName,
+                                             $studentDomain,$fullname,
+                                             $studentSection,$id));
+        }
+    }
+    #
+    # Find discrepancies between the course row table and this
+    #
+    my %f=$self->formulas();
+    my $changed=0;
+    #
+    $self->{'maxrow'}=0;
+    my %existing=();
+    #
+    # Now obsolete rows
+    foreach my $rownum ($self->rows()) {
+        my $cell = 'A'.$rownum;
+        if ($rownum > $self->{'maxrow'}) {
+            $self->{'maxrow'}= $rownum;
+        }
+        $existing{$f{$cell}}=1;
+        if (! defined($currentlist{$f{$cell}}) && ($f{$cell}=~/^(~~~|---)/)) {
+            $f{$cell}='!!! Obsolete';
+            $changed=1;
+        }
+    }
+    #
+    # New and unknown keys
+    foreach my $student (sort keys(%currentlist)) {
+        next if ($existing{$student});
+        $changed=1;
+        $self->{'maxrow'}++;
+        $f{'A'.$self->{'maxrow'}}=$student;
+    }
+    $self->formulas(\%f) if ($changed);
+    #
+    $self->rowlabels(\%currentlist);
+}
 
-# -------------------------------------------------------- New and unknown keys
-     
-        map {
-            unless ($existing{$_}) {
-		$changed=1;
-                $maxrow++;
-                $f{'A'.$maxrow}=$_;
+# ----------------------------------- Update rows for student and assess sheets
+sub get_student_rowlabels {
+    my $self = shift;
+    #
+    my %course_db;
+    #
+    my $stype = $self->{'type'};
+    my $uname = $self->{'uname'};
+    my $udom  = $self->{'udom'};
+    #
+    $self->{'rowlabel'} = {};
+    #
+    my $identifier =$self->{'coursefilename'}.'_'.$stype;
+    if  (exists($rowlabel_cache{$identifier})) {
+        my %tmp = split(/___;___/,$rowlabel_cache{$identifier});
+        $self->rowlabels(\%tmp);
+    } else {
+        # Get the data and store it in the cache
+        # Tie hash
+        tie(%course_db,'GDBM_File',$self->{'coursefilename'}.'.db',
+            &GDBM_READER(),0640);
+        if (! tied(%course_db)) {
+            return 'Could not access course data';
+        }
+        #
+        my %assesslist = ();
+        foreach ('Feedback','Evaluation','Tutoring','Discussion') {
+            my $symb = '_'.lc($_);
+            $assesslist{$symb} = join(':',('symb',$symb,0,0,
+                                           &Apache::lonnet::escape($_)));
+        }
+        #
+        while (my ($key,$srcf) = each(%course_db)) {
+            next if ($key !~ /^src_(\d+)\.(\d+)$/);
+            my $mapid = $1;
+            my $resid = $2;
+            my $id   = $mapid.'.'.$resid;
+            if ($srcf=~/\.(problem|exam|quiz|assess|survey|form)$/) {
+                my $symb=
+                    &Apache::lonnet::declutter($course_db{'map_id_'.$mapid}).
+                        '___'.$resid.'___'.&Apache::lonnet::declutter($srcf);
+                $assesslist{$symb} ='symb:'.&Apache::lonnet::escape($symb).':'
+                    .$mapid.':'.$resid.':'.
+                        &Apache::lonnet::escape($course_db{'title_'.$id});
             }
-        } sort keys %currentlist;        
-     
-        if ($changed) { &setformulas($safeeval,%f); }
-
-        &setmaxrow($safeeval,$maxrow);
-        &setrowlabels($safeeval,%currentlist);
+        }
+        untie(%course_db);
+        # Store away the data
+        $self->{'rowlabel'} = \%assesslist;
+        $rowlabel_cache{$identifier}=join('___;___',%{$self->{'rowlabel'}});
+    }
+    
+}
 
+sub get_assess_rowlabels {
+    my $self = shift;
+    #
+    my %course_db;
+    #
+    my $stype = $self->{'type'};
+    my $uname = $self->{'uname'};
+    my $udom  = $self->{'udom'};
+    my $usymb = $self->{'usymb'};
+    #
+    $self->rowlabels({});
+    my $identifier =$self->{'coursefilename'}.'_'.$stype.'_'.$usymb;
+    #
+    if (exists($rowlabel_cache{$identifier})) {
+        my %tmp = split('___;___',$rowlabel_cache{$identifier});
+        $self->rowlabels(\%tmp);
     } else {
-        return 'Could not access course data';
+        # Get the data and store it in the cache
+        # Tie hash
+        tie(%course_db,'GDBM_File',$self->{'coursefilename'}.'.db',
+            &GDBM_READER(),0640);
+        if (! tied(%course_db)) {
+            return 'Could not access course data';
+        }
+        #
+        my %parameter_labels=
+            ('timestamp' => 
+                 'parameter:Timestamp of Last Transaction<br>timestamp',
+             'subnumber' =>
+                 'parameter:Number of Submissions<br>subnumber',
+             'tutornumber' =>
+                 'parameter:Number of Tutor Responses<br>tutornumber',
+             'totalpoints' =>
+                 'parameter:Total Points Granted<br>totalpoints');
+        while (my ($key,$srcf) = each(%course_db)) {
+            next if ($key !~ /^src_(\d+)\.(\d+)$/);
+            my $mapid = $1;
+            my $resid = $2;
+            my $id   = $mapid.'.'.$resid;
+            if ($srcf=~/\.(problem|exam|quiz|assess|survey|form)$/) {
+                # Loop through the metadata for this key
+                my @Metadata = split(/,/,
+                                     &Apache::lonnet::metadata($srcf,'keys'));
+                foreach my $key (@Metadata) {
+                    next if ($key !~ /^(stores|parameter)_/);
+                    my $display=
+                        &Apache::lonnet::metadata($srcf,$key.'.display');
+                    unless ($display) {
+                        $display.=
+                            &Apache::lonnet::metadata($srcf,$key.'.name');
+                    }
+                    $display.='<br>'.$key;
+                    $parameter_labels{$key}='parameter:'.$display;
+                } # end of foreach
+            }
+        }
+        untie(%course_db);
+        # Store away the results
+        $self->rowlabels(\%parameter_labels);
+        $rowlabel_cache{$identifier}=join('___;___',%parameter_labels);
     }
 }
 
-# ----------------------------------- Update rows for student and assess sheets
-
 sub updatestudentassesssheet {
-    my $safeeval=shift;
-    my %bighash;
-    my $stype=&gettype($safeeval);
-    my %current=();
-    unless ($updatedata{$ENV{'request.course.fn'}.'_'.$stype}) {
-# -------------------------------------------------------------------- Tie hash
-      if (tie(%bighash,'GDBM_File',$ENV{'request.course.fn'}.'.db',
-                       &GDBM_READER,0640)) {
-# --------------------------------------------------------- Get all assessments
-
-	my %allkeys=();
-        my %allassess=();
-
-        map {
-	    if ($_=~/^src\_(\d+)\.(\d+)$/) {
-	       my $mapid=$1;
-               my $resid=$2;
-               my $id=$mapid.'.'.$resid;
-               my $srcf=$bighash{$_};
-               if ($srcf=~/\.(problem|exam|quiz|assess|survey|form)$/) {
-                 my $symb=
-                     &Apache::lonnet::declutter($bighash{'map_id_'.$mapid}).
-			    '___'.$resid.'___'.
-			    &Apache::lonnet::declutter($srcf);
-		 $allassess{$symb}=$bighash{'title_'.$id};
-
-                 if ($stype eq 'assesscalc') {
-                   map {
-                       if (($_=~/^stores\_(.*)/) || ($_=~/^parameter\_(.*)/)) {
-			  my $key=$_;
-                          my $display=
-			      &Apache::lonnet::metadata($srcf,$key.'.display');
-                          unless ($display) {
-                              $display=
-			         &Apache::lonnet::metadata($srcf,$key.'.name');
-                          }
-                          $allkeys{$key}=$display;
-		       }
-                   } split(/\,/,&Apache::lonnet::metadata($srcf,'keys'));
-	         }
-	      }
-	   }
-        } keys %bighash;
-        untie(%bighash);
-    
-#
-# %allkeys has a list of storage and parameter displays by unikey
-# %allassess has a list of all resource displays by symb
-#
-
-        if ($stype eq 'assesscalc') {
-	    %current=%allkeys;
-        } elsif ($stype eq 'studentcalc') {
-            %current=%allassess;
-        }
-        $updatedata{$ENV{'request.course.fn'}.'_'.$stype}=
-	    join('___;___',%current);
-        undef %allkeys;
-        undef %allassess;
+    my $self = shift;
+    if ($self->{'type'} eq 'studentcalc') {
+        $self->get_student_rowlabels();
     } else {
-        return 'Could not access course data';
+        $self->get_assess_rowlabels();
     }
-# ------------------------------------------------------ Get current from cache
-    } else {
-        %current=split(/\_\_\_\;\_\_\_/,
-		       $updatedata{$ENV{'request.course.fn'}.'_'.$stype});
+    # Determine if any of the information has changed
+    my %f=$self->formulas();
+    my $changed=0;
+    $self->{'maxrow'} = 0;
+    my %existing=();
+    # Now obsolete rows
+    foreach my $rownum ($self->rows()) {
+        my $cell = 'A'.$rownum;
+        my $formula = $f{$cell};
+        $self->{'maxrow'} = $rownum if ($rownum > $self->{'maxrow'});
+        my ($usy,$ufn)=split(/__&&&\__/,$formula);
+        $existing{$usy}=1;
+        if ( ! exists($self->{'rowlabel'}->{$usy})  ||
+             ! defined($self->{'rowlabel'}->{$usy}) ||
+             ($formula =~ /^(~~~|---)/) ||
+             ($formula =~ /^\s*$/)) {
+            $f{$cell}='!!! Obsolete';
+            $changed=1;
+        }
     }
-# -------------------- Find discrepancies between the course row table and this
-#
-        my %f=&getformulas($safeeval);
-        my $changed=0;
-
-        my $maxrow=0;
-        my %existing=();
-
-# ----------------------------------------------------------- Now obsolete rows
-	map {
-	    if ($_=~/^A(\d+)/) {
-                $maxrow=($1>$maxrow)?$1:$maxrow;
-                $existing{$f{$_}}=1;
-		unless ((defined($current{$f{$_}})) || (!$1)) {
-		   $f{$_}='!!! Obsolete';
-                   $changed=1;
-                }
-            }
-        } keys %f;
-
-# -------------------------------------------------------- New and unknown keys
-     
-        map {
-            unless ($existing{$_}) {
-		$changed=1;
-                $maxrow++;
-                $f{'A'.$maxrow}=$_;
-            }
-        } keys %current;        
-    
-        if ($changed) { &setformulas($safeeval,%f); }
-
-        &setmaxrow($safeeval,$maxrow);
-        &setrowlabels($safeeval,%current);
- 
-        undef %current;
-        undef %existing;
+    # New and unknown keys
+    my %keys_hates_me = $self->rowlabels();
+    foreach (keys(%keys_hates_me)) {
+        unless ($existing{$_}) {
+            $changed=1;
+            $self->{'maxrow'}++;
+            $f{'A'.$self->{'maxrow'}}=$_;
+        }
+    }
+    $self->formulas(\%f) if ($changed);
+#    $self->dump_formulas_to_log();    
 }
 
 # ------------------------------------------------ Load data for one assessment
-
-sub loadstudent {
-    my $safeeval=shift;
-    my %c=();
-    my %f=&getformulas($safeeval);
-    map {
-	if ($_=~/^A(\d+)/) {
-	   my $row=$1;
-           unless ($f{$_}=~/^\!/) {
-	      my @assessdata=&exportsheet(&getuname($safeeval),
-                                          &getudom($safeeval),
-                                          'assesscalc',$f{$_});
-              my $index=0;
-              map {
-                  if ($assessdata[$index]) {
-		     $c{$_.$row}=$assessdata[$index];
-                     unless ($_ eq 'A') { 
-			 $f{$_.$row}='import';
-                     }
-		  }
-                  $index++;
-              } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-                 'N','O','P','Q','R','S','T','U','V','W','X','Y','Z');
-	   }
+sub loadstudent{
+    my $self = shift;
+    my ($r,$c)=@_;
+    my %constants = ();
+    my %formulas  = $self->formulas();
+    $cachedassess = $self->{'uname'}.':'.$self->{'udom'};
+    # Get ALL the student preformance data
+    my @tmp = &Apache::lonnet::currentdump($self->{'uname'},
+                                           $self->{'udom'},
+                                           $self->{'cid'});
+    if ((scalar @tmp > 0) && ($tmp[0] !~ /^error:/)) {
+        %cachedstores = @tmp;
+    }
+    undef @tmp;
+    # 
+    my @assessdata=();
+    foreach my $row ($self->rows()) {
+        my $cell = 'A'.$row;
+        my $value = $formulas{$cell};
+        if(defined($c) && ($c->aborted())) {
+            last;
+        }
+        next if ($value =~ /^[!~-]/);
+        my ($usy,$ufn)=split(/__&&&\__/,$value);
+        @assessdata=$self->exportsheet($self->{'uname'},
+                                        $self->{'udom'},
+                                        'assesscalc',$usy,$ufn,$r);
+        my $index=0;
+        foreach my $col ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+                         'N','O','P','Q','R','S','T','U','V','W','X','Y','Z') {
+            if (defined($assessdata[$index])) {
+                if ($assessdata[$index]=~/\D/) {
+                    $constants{$col.$row}="'".$assessdata[$index]."'";
+                } else {
+                    $constants{$col.$row}=$assessdata[$index];
+                }
+                $formulas{$col.$row}='import' if ($col ne 'A');
+            }
+            $index++;
         }
-    } keys %f;
-    &setformulas($safeeval,%f);
-    &setconstants($safeeval,%c);
+    }
+    $cachedassess='';
+    undef %cachedstores;
+    $self->formulas(\%formulas);
+    $self->constants(\%constants);
 }
 
 # --------------------------------------------------- Load data for one student
-
+#
 sub loadcourse {
-    my $safeeval=shift;
-    my %c=();
-    my %f=&getformulas($safeeval);
-    map {
-	if ($_=~/^A(\d+)/) {
-	   my $row=$1;
-           unless (($f{$_}=~/^\!/)
-|| ($row>200))
- {
-	      my @studentdata=&exportsheet(&getuname($safeeval),
-                                           &getudom($safeeval),
-                                           'studentcalc');
-              undef %userrdatas; 
-              my $index=0;
-              map {
-                  if ($studentdata[$index]) {
-		     $c{$_.$row}=$studentdata[$index];
-                     unless ($_ eq 'A') { 
-			 $f{$_.$row}='import';
-                     }
-		  }
-                  $index++;
-              } ('A','B','C','D','E','F','G','H','I','J','K','L','M',
-                 'N','O','P','Q','R','S','T','U','V','W','X','Y','Z');
-	   }
+    my $self = shift;
+    my ($r,$c)=@_;
+    #
+    my %constants=();
+    my %formulas=$self->formulas();
+    #
+    my $total=0;
+    foreach ($self->rows()) {
+        $total++ if ($formulas{'A'.$_} !~ /^[!~-]/);
+    }
+    my $now=0;
+    my $since=time;
+    $r->print(<<ENDPOP);
+<script>
+    popwin=open('','popwin','width=400,height=100');
+    popwin.document.writeln('<html><body bgcolor="#FFFFFF">'+
+      '<h3>Spreadsheet Calculation Progress</h3>'+
+      '<form name=popremain>'+
+      '<input type=text size=45 name=remaining value=Starting></form>'+
+      '</body></html>');
+    popwin.document.close();
+</script>
+ENDPOP
+    $r->rflush();
+    # It would be nice to load in the classlist and assessment info at this 
+    # point, before attacking the student spreadsheets.
+    foreach my $row ($self->rows()) {
+        if(defined($c) && ($c->aborted())) {
+            last;
         }
-    } keys %f;
-    &setformulas($safeeval,%f);
-    &setconstants($safeeval,%c);
+        my $cell = 'A'.$row;
+        next if ($formulas{$cell}=~/^[\!\~\-]/);
+        my ($sname,$sdom) = split(':',$formulas{$cell});
+        my $started = time;
+        my @studentdata=$self->exportsheet($sname,$sdom,'studentcalc',
+                                     undef,undef,$r);
+        undef %userrdatas;
+        $now++;
+        $r->print('<script>popwin.document.popremain.remaining.value="'.
+                  $now.'/'.$total.': '.int((time-$since)/$now*($total-$now)).
+                  ' secs remaining '.(time-$started).' last";</script>');
+        $r->rflush(); 
+        #
+        my $index=0;
+        foreach ('A','B','C','D','E','F','G','H','I','J','K','L','M',
+                 'N','O','P','Q','R','S','T','U','V','W','X','Y','Z') {
+            if (defined($studentdata[$index])) {
+                my $col=$_;
+                if ($studentdata[$index]=~/\D/) {
+                    $constants{$col.$row}="'".$studentdata[$index]."'";
+                } else {
+                    $constants{$col.$row}=$studentdata[$index];
+                }
+                unless ($col eq 'A') { 
+                    $formulas{$col.$row}='import';
+                }
+            } 
+            $index++;
+        }
+    }
+    $self->formulas(\%formulas);
+    $self->constants(\%constants);
+    $r->print('<script>popwin.close()</script>');
+    $r->rflush(); 
 }
 
 # ------------------------------------------------ Load data for one assessment
-
+#
 sub loadassessment {
-    my $safeeval=shift;
+    my $self = shift;
+    my ($r,$c)=@_;
 
-    my $uhome=&getuhome($safeeval);
-    my $uname=&getuname($safeeval);
-    my $udom=&getudom($safeeval);
-    my $symb=&getusymb($safeeval);
-    my $cid=&getcid($safeeval);
-    my $cnum=&getcnum($safeeval);
-    my $cdom=&getcdom($safeeval);
-    my $chome=&getchome($safeeval);
+    my $uhome = $self->{'uhome'};
+    my $uname = $self->{'uname'};
+    my $udom  = $self->{'udom'};
+    my $symb  = $self->{'usymb'};
+    my $cid   = $self->{'cid'};
+    my $cnum  = $self->{'cnum'};
+    my $cdom  = $self->{'cdom'};
+    my $chome = $self->{'chome'};
+    my $csec  = $self->{'csec'};
 
     my $namespace;
     unless ($namespace=$cid) { return ''; }
-
-# ----------------------------------------------------------- Get stored values
-    my $answer=&Apache::lonnet::reply(
-       "restore:$udom:$uname:".
-       &Apache::lonnet::escape($namespace).":".
-       &Apache::lonnet::escape($symb),$uhome);
+    # Get stored values
     my %returnhash=();
-    map {
-	my ($name,$value)=split(/\=/,$_);
-        $returnhash{&Apache::lonnet::unescape($name)}=
-                    &Apache::lonnet::unescape($value);
-    } split(/\&/,$answer);
-    my $version;
-    for ($version=1;$version<=$returnhash{'version'};$version++) {
-       map {
-          $returnhash{$_}=$returnhash{$version.':'.$_};
-       } split(/\:/,$returnhash{$version.':keys'});
+    if ($cachedassess eq $uname.':'.$udom) {
+        #
+        # get data out of the dumped stores
+        # 
+        if (exists($cachedstores{$symb})) {
+            %returnhash = %{$cachedstores{$symb}};
+        } else {
+            %returnhash = ();
+        }
+    } else {
+        #
+        # restore individual
+        #
+        %returnhash = &Apache::lonnet::restore($symb,$namespace,$udom,$uname);
+    }
+    #
+    # returnhash now has all stores for this resource
+    # convert all "_" to "." to be able to use libraries, multiparts, etc
+    #
+    # This is dumb.  It is also necessary :(
+    my @oldkeys=keys %returnhash;
+    #
+    foreach my $name (@oldkeys) {
+        my $value=$returnhash{$name};
+        delete $returnhash{$name};
+        $name=~s/\_/\./g;
+        $returnhash{$name}=$value;
     }
-# ----------------------------- returnhash now has all stores for this resource
-
-# ---------------------------- initialize coursedata and userdata for this user
+    # initialize coursedata and userdata for this user
     undef %courseopt;
     undef %useropt;
 
     my $userprefix=$uname.'_'.$udom.'_';
 
     unless ($uhome eq 'no_host') { 
-# -------------------------------------------------------------- Get coursedata
-      unless
-        ((time-$courserdatas{$cid.'.last_cache'})<240) {
-         my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum.
-              ':resourcedata',$chome);
-         if ($reply!~/^error\:/) {
-            $courserdatas{$cid}=$reply;
+        # Get coursedata
+        unless ((time-$courserdatas{$cid.'.last_cache'})<240) {
+            my %Tmp = &Apache::lonnet::dump('resourcedata',$cdom,$cnum);
+            $courserdatas{$cid}=\%Tmp;
             $courserdatas{$cid.'.last_cache'}=time;
-         }
-      }
-      map {
-         my ($name,$value)=split(/\=/,$_);
-         $courseopt{$userprefix.&Apache::lonnet::unescape($name)}=
-                    &Apache::lonnet::unescape($value);  
-      } split(/\&/,$courserdatas{$ENV{'request.course.id'}});
-# --------------------------------------------------- Get userdata (if present)
-      unless
-        ((time-$userrdatas{$uname.'___'.$udom.'.last_cache'})<240) {
-         my $reply=
-       &Apache::lonnet::reply('dump:'.$udom.':'.$uname.':resourcedata',$uhome);
-         if ($reply!~/^error\:/) {
-	     $userrdatas{$uname.'___'.$udom}=$reply;
-	     $userrdatas{$uname.'___'.$udom.'.last_cache'}=time;
-         }
-      }
-      map {
-         my ($name,$value)=split(/\=/,$_);
-         $useropt{$userprefix.&Apache::lonnet::unescape($name)}=
-	          &Apache::lonnet::unescape($value);
-      } split(/\&/,$userrdatas{$uname.'___'.$udom});
-    }
-
-# ----------------- now courseopt, useropt initialized for this user and course
-# (used by parmval)
-
-   my %c=();
-
-   if (tie(%parmhash,'GDBM_File',
-           &getcfn($safeeval).'_parms.db',&GDBM_READER,0640)) {
-    my %f=&getformulas($safeeval);
-    map {
-	if ($_=~/^A/) {
-            unless ($f{$_}=~/^\!/) {
-  	       if ($f{$_}=~/^parameter/) {
-	          $c{$_}=&parmval($f{$_},$safeeval);
-	       } else {
-		  my $key=$f{$_};
-                  $key=~s/^stores\_/resource\./;
-                  $key=~s/\_/\./;
- 	          $c{$_}=$returnhash{$key};
-	       }
-	   }
         }
-    } keys %f;
-    untie(%parmhash);
-   }
-   &setconstants($safeeval,%c);
-}
-
-# --------------------------------------------------------- Various form fields
-
-sub textfield {
-    my ($title,$name,$value)=@_;
-    return "\n<p><b>$title:</b><br>".
-           '<input type=text name="'.$name.'" size=80 value="'.$value.'">';
-}
-
-sub hiddenfield {
-    my ($name,$value)=@_;
-    return "\n".'<input type=hidden name="'.$name.'" value="'.$value.'">';
+        while (my ($name,$value) = each(%{$courserdatas{$cid}})) {
+            $courseopt{$userprefix.$name}=$value;
+        }
+        # Get userdata (if present)
+        unless ((time-$userrdatas{$uname.'@'.$udom.'.last_cache'})<240) {
+            my %Tmp = &Apache::lonnet::dump('resourcedata',$udom,$uname);
+            $userrdatas{$cid} = \%Tmp;
+            # Most of the time the user does not have a 'resourcedata.db' 
+            # file.  We need to cache that we got nothing instead of bothering
+            # with requesting it every time.
+            $userrdatas{$uname.'@'.$udom.'.last_cache'}=time;
+        }
+        while (my ($name,$value) = each(%{$userrdatas{$cid}})) {
+            $useropt{$userprefix.$name}=$value;
+        }
+    }
+    # now courseopt, useropt initialized for this user and course
+    # (used by parmval)
+    #
+    # Load keys for this assessment only
+    #
+    my %thisassess=();
+    my ($symap,$syid,$srcf)=split(/\_\_\_/,$symb);
+    foreach (split(/\,/,&Apache::lonnet::metadata($srcf,'keys'))) {
+        $thisassess{$_}=1;
+    } 
+    #
+    # Load parameters
+    #
+    my %c=();
+    if (tie(%parmhash,'GDBM_File',
+            $self->{'coursefilename'}.'_parms.db',&GDBM_READER(),0640)) {
+        my %f=$self->formulas();
+        foreach my $row ($self->rows())  {
+            my $cell = 'A'.$row;
+            my $formula = $self->formula($cell);
+            next if ($formula =~/^[\!\~\-]/);
+            if ($formula =~ /^parameter/) {
+                if (defined($thisassess{$formula})) {
+                    my $val   = &parmval($formula,$symb,$uname,$udom,$csec);
+                    $c{$cell}    = $val;
+                    $c{$formula} = $val;
+                }
+            } else {
+                my $ckey=$formula;
+                $formula=~s/^stores\_/resource\./;
+                $formula=~s/\_/\./g;
+                $c{$cell}=$returnhash{$formula};
+                $c{$ckey}=$returnhash{$formula};
+            }
+        }
+        untie(%parmhash);
+    }
+    $self->constants(\%c);
 }
 
-sub selectbox {
-    my ($title,$name,$value,%options)=@_;
-    my $selout="\n<p><b>$title:</b><br>".'<select name="'.$name.'">';
-    map {
-        $selout.='<option value="'.$_.'"';
-        if ($_ eq $value) { $selout.=' selected'; }
-        $selout.='>'.$options{$_}.'</option>';
-    } sort keys %options;
-    return $selout.'</select>';
-}
 
 # =============================================== Update information in a sheet
 #
 # Add new users or assessments, etc.
 #
-
 sub updatesheet {
-    my $safeeval=shift;
-    my $stype=&gettype($safeeval);
-    if ($stype eq 'classcalc') {
-	return &updateclasssheet($safeeval);
+    my $self = shift;
+    if ($self->{'type'} eq 'classcalc') {
+        return $self->updateclasssheet();
     } else {
-        return &updatestudentassesssheet($safeeval);
+        return $self->updatestudentassesssheet();
     }
 }
 
@@ -1375,247 +3377,152 @@ sub updatesheet {
 #
 # Import the data for rows
 #
-
-sub loadrows() {
-    my $safeeval=shift;
-    my $stype=&gettype($safeeval);
-    if ($stype eq 'classcalc') {
-	&loadcourse($safeeval);
-    } elsif ($stype eq 'studentcalc') {
-        &loadstudent($safeeval);
+sub loadrows {
+    my $self = shift;
+    my ($r)=@_;
+    my $c = $r->connection;
+    if ($self->{'type'} eq 'classcalc') {
+        $self->loadcourse($r,$c);
+    } elsif ($self->{'type'} eq 'studentcalc') {
+        $self->loadstudent($r,$c);
     } else {
-        &loadassessment($safeeval);
+        $self->loadassessment($r,$c);
     }
 }
 
 # ============================================================== Export handler
+# exportsheet
+# returns the export row for a spreadsheet.
 #
-# Non-interactive call from with program
-#
-
 sub exportsheet {
-    my ($uname,$udom,$stype,$usymb,$fn)=@_;
-    my $thissheet=&makenewsheet($uname,$udom,$stype,$usymb);
-    &readsheet($thissheet,$fn);
-    &updatesheet($thissheet);
-    &loadrows($thissheet);
-    &calcsheet($thissheet);
-    my @returnthis=&exportdata($thissheet);
-    undef $thissheet;
-    return @returnthis;
-}
-
-# ================================================================ Main handler
-#
-# Interactive call to screen
-#
-#
-
-
-sub handler {
-    my $r=shift;
-
-    if ($r->header_only) {
-      $r->content_type('text/html');
-      $r->send_http_header;
-      return OK;
+    my $self = shift;
+    my ($uname,$udom,$stype,$usymb,$fn,$r)=@_;
+    my $flag = 0;
+    $uname = $uname || $self->{'uname'};
+    $udom  = $udom  || $self->{'udom'};
+    $stype = $stype || $self->{'type'};
+    my @exportarr=();
+    # This handles the assessment sheets for '_feedback', etc
+    if (defined($usymb) && ($usymb=~/^\_(\w+)/) && 
+        (!defined($fn) || $fn eq '')) {
+        $fn='default_'.$1;
+    }
+    #
+    # Check if cached
+    #
+    my $key=$uname.':'.$udom.':'.$stype.':'.$usymb;
+    my $found='';
+    if ($Apache::lonspreadsheet::oldsheets{$key}) {
+        foreach (split(/___&\___/,$Apache::lonspreadsheet::oldsheets{$key})) {
+            my ($name,$value)=split(/___=___/,$_);
+            if ($name eq $fn) {
+                $found=$value;
+            }
+        }
     }
-
-# ---------------------------------------------------- Global directory configs
-
-$includedir=$r->dir_config('lonIncludes');
-$tmpdir=$r->dir_config('lonDaemons').'/tmp/';
-
-# ----------------------------------------------------- Needs to be in a course
-
-  if ($ENV{'request.course.fn'}) { 
-
-# --------------------------- Get query string for limited number of parameters
-
-    map {
-       my ($name, $value) = split(/=/,$_);
-       $value =~ tr/+/ /;
-       $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
-       if (($name eq 'uname') || ($name eq 'udom') || 
-           ($name eq 'usymb') || ($name eq 'ufn')) {
-           unless ($ENV{'form.'.$name}) {
-              $ENV{'form.'.$name}=$value;
-	   }
-       }
-    } (split(/&/,$ENV{'QUERY_STRING'}));
-
-# ------------------------------------------- Nothing there? Must be login user
-
-    my $aname;
-    my $adom;
-
-    unless ($ENV{'form.uname'}) {
-	$aname=$ENV{'user.name'};
-        $adom=$ENV{'user.domain'};
-    } else {
-        $aname=$ENV{'form.uname'};
-        $adom=$ENV{'form.udom'};
+    unless ($found) {
+        &cachedssheets($self,$uname,$udom);
+        if ($Apache::lonspreadsheet::oldsheets{$key}) {
+            foreach (split(/___&\___/,$Apache::lonspreadsheet::oldsheets{$key})) {
+                my ($name,$value)=split(/___=___/,$_);
+                if ($name eq $fn) {
+                    $found=$value;
+                }
+            } 
+        }
     }
-
-# ------------------------------------------------------------------- Open page
-
-    $r->content_type('text/html');
-    $r->header_out('Cache-control','no-cache');
-    $r->header_out('Pragma','no-cache');
-    $r->send_http_header;
-
-# --------------------------------------------------------------- Screen output
-
-    $r->print('<html><head><title>LON-CAPA Spreadsheet</title>');
-    $r->print(<<ENDSCRIPT);
-<script language="JavaScript">
-
-    function celledit(cn,cf) {
-        var cnf=prompt(cn,cf);
-	if (cnf!=null) {
-	    document.sheet.unewfield.value=cn;
-            document.sheet.unewformula.value=cnf;
-            document.sheet.submit();
+    #
+    # Check if still valid
+    #
+    if ($found) {
+        if (&forcedrecalc($uname,$udom,$stype,$usymb)) {
+            $found='';
         }
     }
-
-</script>
-ENDSCRIPT
-    $r->print('</head><body bgcolor="#FFFFFF">'.
-       '<img align=right src=/adm/lonIcons/lonlogos.gif>'.
-       '<h1>LON-CAPA Spreadsheet</h1>'.
-       '<form action="'.$r->uri.'" name=sheet method=post>'.
-       &hiddenfield('uname',$ENV{'form.uname'}).
-       &hiddenfield('udom',$ENV{'form.udom'}).
-       &hiddenfield('usymb',$ENV{'form.usymb'}).
-       &hiddenfield('unewfield','').
-       &hiddenfield('unewformula',''));
-
-# ---------------------- Make sure that this gets out, even if user hits "stop"
-
-    $r->rflush();
-
-# ---------------------------------------- Read new sheet or modified worksheet
-
-    $r->uri=~/\/(\w+)$/;
-
-    my $asheet=&makenewsheet($aname,$adom,$1,$ENV{'form.usymb'});
-
-# ------------------------ If a new formula had been entered, go from work copy
-
-    if ($ENV{'form.unewfield'}) {
-        $r->print('<h2>Modified Workcopy</h2>');
-        $ENV{'form.unewformula'}=~s/\'/\"/g;
-        $r->print('<p>New formula: '.$ENV{'form.unewfield'}.'='.
-                  $ENV{'form.unewformula'}.'<p>');
-        &setfilename($asheet,$ENV{'form.ufn'});
-	&tmpread($asheet,
-                 $ENV{'form.unewfield'},$ENV{'form.unewformula'});
-
-     } elsif ($ENV{'form.saveas'}) {
-        &setfilename($asheet,$ENV{'form.ufn'});
-	&tmpread($asheet);
-    } else {
-        &readsheet($asheet,$ENV{'form.ufn'});
-    }
-
-# -------------------------------------------------- Print out user information
-
-    unless (&gettype($asheet) eq 'classcalc') {
-        $r->print('<p><b>User:</b> '.&getuname($asheet).
-                  '<br><b>Domain:</b> '.&getudom($asheet));
-        if (&getcsec($asheet) eq '-1') {
-           $r->print('<h3><font color=red>'.
-                     'Not a student in this course</font></h3>');
-        } else {
-           $r->print('<br><b>Section/Group:</b> '.&getcsec($asheet));
+    if ($found) {
+        #
+        # Return what was cached
+        #
+        @exportarr=split(/___;___/,$found);
+        return @exportarr;
+    }
+    #
+    # Not cached
+    #
+    my $newsheet = Apache::lonspreadsheet::Spreadsheet->new($uname,$udom,
+                                                         $stype,$usymb);
+    $newsheet->readsheet($fn);
+    $newsheet->updatesheet();
+    $newsheet->loadrows($r);
+    $newsheet->calcsheet(); 
+    @exportarr=$newsheet->exportdata();
+    ##
+    ## Store now
+    ##
+    #
+    # load in the old value
+    #
+    my %currentlystored=();
+    if ($stype eq 'studentcalc') {
+        my @tmp = &Apache::lonnet::get('nohist_calculatedsheets',
+                                       [$key],
+                                       $self->{'cdom'},$self->{'cnum'});
+        if ($tmp[0]!~/^error/) {
+            # We only got one key, so we will access it directly.
+            foreach (split('___&___',$tmp[1])) {
+                my ($key,$value) = split('___=___',$_);
+                $key = '' if (! defined($key));
+                $currentlystored{$key} = $value;
+            }
+        }
+    } else {
+        my @tmp = &Apache::lonnet::get('nohist_calculatedsheets_'.
+                                       $self->{'cid'},[$key],
+                                       $self->{'udom'},$self->{'uname'});
+        if ($tmp[0]!~/^error/) {
+            # We only got one key, so we will access it directly.
+            foreach (split('___&___',$tmp[1])) {
+                my ($key,$value) = split('___=___',$_);
+                $key = '' if (! defined($key));
+                $currentlystored{$key} = $value;
+            }
         }
     }
-
-# ---------------------------------------------------------------- Course title
-
-    $r->print('<h1>'.
-            $ENV{'course.'.$ENV{'request.course.id'}.'.description'}.'</h1>');
-
-
-# ---------------------------------------------------- See if something to save
-
-    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
-        my $fname='';
-	if ($ENV{'form.saveas'} && ($fname=$ENV{'form.newfn'})) {
-            $fname=~s/\W/\_/g;
-            if ($fname eq 'default') { $fname='course_default'; }
-            $fname.='_'.&gettype($asheet);
-            &setfilename($asheet,$fname);
-            $ENV{'form.ufn'}=$fname;
-	    $r->print('<p>Saving spreadsheet: '.
-                         &writesheet($asheet,$ENV{'form.makedefufn'}).'<p>');
-	}
+    #
+    # Add the new line
+    #
+    $currentlystored{$fn}=join('___;___',@exportarr);
+    #
+    # Stick everything back together
+    #
+    my $newstore='';
+    foreach (keys(%currentlystored)) {
+        if ($newstore) { $newstore.='___&___'; }
+        $newstore.=$_.'___=___'.$currentlystored{$_};
     }
-
-# ------------------------------------------------ Write the modified worksheet
-
-   $r->print('<b>Current sheet:</b> '.&getfilename($asheet).'<p>');
-
-   &tmpwrite($asheet);
-
-# ----------------------------------------------------------------- Save dialog
-
-
-    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
-        my $fname=$ENV{'form.ufn'};
-        $fname=~s/\_[^\_]+$//;
-        if ($fname eq 'default') { $fname='course_default'; }
-        $r->print('<input type=submit name=saveas value="Save as ...">'.
-              '<input type=text size=20 name=newfn value="'.$fname.
-              '"> (make default: <input type=checkbox name="makedefufn">)<p>');
+    my $now=time;
+    #
+    # Store away the new value
+    #
+    my $timekey = $key.'.time';
+    if ($stype eq 'studentcalc') {
+        my $result = &Apache::lonnet::put('nohist_calculatedsheets',
+                                          { $key     => $newstore,
+                                            $timekey => $now },
+                                          $self->{'cdom'},
+                                          $self->{'cnum'});
+    } else {
+        my $result = &Apache::lonnet::put('nohist_calculatedsheets_'.$self->{'cid'},
+                                          { $key     => $newstore,
+                                            $timekey => $now },
+                                          $self->{'udom'},
+                                          $self->{'uname'});
     }
-
-    $r->print(&hiddenfield('ufn',&getfilename($asheet)));
-
-
-# ----------------------------------------------------- Update sheet, load rows
-
-    &updatesheet($asheet);
-    &loadrows($asheet);
-
-
-    my $calcoutput=&calcsheet($asheet);
-    $r->print('<h3><font color=red>'.$calcoutput.'</h3></font>');
-
-    &outsheet($r,$asheet);
-    $r->print('</form></body></html>');
-
-# --------------------------------- We know this leaks, so terminate this child
-
-    $r->child_terminate();
-
-# ------------------------------------------------------------------------ Done
-  } else {
-# ----------------------------- Not in a course, or not allowed to modify parms
-      $ENV{'user.error.msg'}=
-        $r->uri.":opa:0:0:Cannot modify spreadsheet";
-      return HTTP_NOT_ACCEPTABLE; 
-  }
-    return OK;
-
+    return @exportarr;
 }
 
 1;
-__END__
-
-
-
-
-
-
-
-
-
-
-
-
-
 
+__END__