--- loncom/interface/Attic/lonspreadsheet.pm	2001/03/10 22:30:18	1.42
+++ loncom/interface/Attic/lonspreadsheet.pm	2001/11/05 18:22:24	1.73
@@ -4,7 +4,10 @@
 # 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,
 # 01/01/01,02/01,03/01,19/01,20/01,22/01,
-# 03/05,03/08,03/10 Gerd Kortemeyer
+# 03/05,03/08,03/10,03/12,03/13,03/15,03/17,
+# 03/19,03/20,03/21,03/27,04/05,04/09,
+# 07/09,07/14,07/21,09/01,09/10,9/11,9/12,9/13,9/14,9/17,
+# 10/16,10/17,10/20,11/05 Gerd Kortemeyer
 
 package Apache::lonspreadsheet;
             
@@ -18,6 +21,14 @@ use GDBM_File;
 use HTML::TokeParser;
 
 #
+# Caches for previously calculated spreadsheets
+#
+
+my %oldsheets;
+my %loadedcaches;
+my %expiredates;
+
+#
 # Cache for stores of an individual user
 #
 
@@ -68,12 +79,14 @@ sub initsheet {
 # v: output values
 # c: preloaded constants (A-column)
 # rl: row label
+# os: other spreadsheets (for student spreadsheet only)
 
 undef %v; 
 undef %t;
 undef %f;
 undef %c;
 undef %rl;
+undef @os;
 
 $maxrow=0;
 $sheettype='';
@@ -296,6 +309,42 @@ sub SUMMIN {
     return $sum;   
 }
 
+sub expandnamed {
+    my $expression=shift;
+    if ($expression=~/^\&/) {
+	my ($func,$var,$formula)=($expression=~/^\&(\w+)\(([^\;]+)\;(.*)\)/);
+	my @vars=split(/\W+/,$formula);
+        my %values=();
+        undef %values;
+        map {
+            my $varname=$_;
+            if ($varname=~/\D/) {
+               $formula=~s/$varname/'$c{\''.$varname.'\'}'/ge;
+               $varname=~s/$var/\(\\w\+\)/g;
+	       map {
+		  if ($_=~/$varname/) {
+		      $values{$1}=1;
+                  }
+               } keys %c;
+	    }
+        } @vars;
+        if ($func eq 'EXPANDSUM') {
+            my $result='';
+	    map {
+                my $thissum=$formula;
+                $thissum=~s/$var/$_/g;
+                $result.=$thissum.'+';
+            } keys %values;
+            $result=~s/\+$//;
+            return $result;
+        } else {
+	    return 0;
+        }
+    } else {
+        return '$c{\''.$expression.'\'}';
+    }
+}
+
 sub sett {
     %t=();
     my $pattern='';
@@ -317,7 +366,7 @@ sub sett {
                     $t{$lb}=~s/\#/$trow/g;
                     $t{$lb}=~s/\.\.+/\,/g;
                     $t{$lb}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
-                    $t{$lb}=~s/(^|[^\"\'])\[(\w+)\]/$1\$c\{\'$2\'\}/g;
+                    $t{$lb}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.&expandnamed($2)/ge;
                 }
 	      }
             } keys %f;
@@ -335,14 +384,14 @@ sub sett {
 	       $t{$_}=$f{$_};
                $t{$_}=~s/\.\.+/\,/g;
                $t{$_}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
-               $t{$_}=~s/(^|[^\"\'])\[([\w\.]+)\]/$1\$c\{\'$2\'\}/g;
+               $t{$_}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.&expandnamed($2)/ge;
             }
         }
     } keys %f;
     $t{'A0'}=$f{'A0'};
     $t{'A0'}=~s/\.\.+/\,/g;
     $t{'A0'}=~s/(^|[^\"\'])([A-Za-z]\d+)/$1\$v\{\'$2\'\}/g;
-    $t{'A0'}=~s/(^|[^\"\'])\[([\w\.]+)\]/$1\$c\{\'$2\'\}/g;
+    $t{'A0'}=~s/(^|[^\"\'])\[([^\]]+)\]/$1.&expandnamed($2)/ge;
 }
 
 sub calc {
@@ -388,7 +437,18 @@ sub outrowassess {
     my $n=shift;
     my @cols=();
     if ($n) {
-       $cols[0]=$rl{$f{'A'.$n}};
+       my ($usy,$ufn)=split(/\_\_\&\&\&\_\_/,$f{'A'.$n});
+       $cols[0]=$rl{$usy}.'<br>'.
+                '<select name="sel_'.$n.'" onChange="changesheet('.$n.
+                ')"><option name="default">Default</option>';
+       map {
+           $cols[0].='<option name="'.$_.'"';
+            if ($ufn eq $_) {
+               $cols[0].=' selected';
+            }
+            $cols[0].='>'.$_.'</option>';
+       } @os;
+       $cols[0].='</select>';
     } else {
        $cols[0]='<b><font size=+1>Export</font></b>';
     }
@@ -451,6 +511,13 @@ sub setconstants {
     %{$safeeval->varglob('c')}=%c;
 }
 
+# --------------------------------------------- Set names of other spreadsheets
+
+sub setothersheets {
+    my ($safeeval,@os)=@_;
+    @{$safeeval->varglob('os')}=@os;
+}
+
 # ------------------------------------------------ Add or change formula values
 
 sub setrowlabels {
@@ -591,6 +658,7 @@ sub exportdata {
     return $safeeval->reval('&exportrowa()');
 }
 
+
 # ========================================================== End of Spreadsheet
 # =============================================================================
 
@@ -603,44 +671,40 @@ sub rown {
     my ($safeeval,$n)=@_;
     my $defaultbg;
     my $rowdata='';
+    my $dataflag=0;
     unless ($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');
-        $rowdata.='</tr>';
+    unless ($ENV{'form.showcsv'}) {
+       $rowdata.="\n<tr><td><b><font size=+1>$n</font></b></td>";
+    } else {
+       $rowdata.="\n".'"'.$n.'"';
     }
-    $rowdata.="\n<tr><td><b><font size=+1>$n</font></b></td>";
     my $showf=0;
     my $proc;
     my $maxred;
-    if (&gettype($safeeval) eq 'assesscalc') {
+    my $sheettype=&gettype($safeeval);
+    if ($sheettype eq 'studentcalc') {
         $proc='&outrowassess';
-        $maxred=1;
+        $maxred=26;
     } else {
         $proc='&outrow';
+    }
+    if ($sheettype eq 'assesscalc') {
+        $maxred=1;
+    } else {
         $maxred=26;
     }
-    if ($n eq '-') { $proc='&templaterow'; $n=-1; }
+    if ($n eq '-') { $proc='&templaterow'; $n=-1; $dataflag=1; }
     map {
        my $bgcolor=$defaultbg.((($showf-1)/5==int(($showf-1)/5))?'99':'DD');
        my ($fm,$vl)=split(/\_\_\_eq\_\_\_/,$_);
+       if ((($vl ne '') || ($vl eq '0')) &&
+           (($showf==1) || ($sheettype ne 'studentcalc'))) { $dataflag=1; }
        if ($showf==0) { $vl=$_; }
+      unless ($ENV{'form.showcsv'}) {
        if ($showf<=$maxred) { $bgcolor='#FFDDDD'; }
        if (($n==0) && ($showf<=26)) { $bgcolor='#CCCCFF'; } 
        if (($showf>$maxred) || ((!$n) && ($showf>0))) {
@@ -653,9 +717,16 @@ sub rown {
        } else {
            $rowdata.='<td bgcolor='.$bgcolor.'>&nbsp;'.$vl.'&nbsp;</td>';
        }
+      } else {
+	  $rowdata.=',"'.$vl.'"';
+      }
        $showf++;
     } $safeeval->reval($proc.'('.$n.')');
-    return $rowdata.'</tr>';
+    if ($ENV{'form.showall'} || ($dataflag)) {
+       return $rowdata.($ENV{'form.showcsv'}?'':'</tr>');
+    } else {
+       return '';
+    }
 }
 
 # ------------------------------------------------------------- Print out sheet
@@ -675,7 +746,9 @@ sub outsheet {
         $realm='Course';
     }
     my $maxyellow=52-$maxred;
-    my $tabledata=
+    my $tabledata;
+    unless ($ENV{'form.showcsv'}) {
+       $tabledata=
         '<table border=2><tr><th colspan=2 rowspan=2><font size=+2>'.
                   $realm.'</font></th>'.
                   '<td bgcolor=#FFDDDD colspan='.$maxred.
@@ -695,15 +768,73 @@ sub outsheet {
        '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>';
+    $tabledata.='</tr>'.&rown($safeeval,'-').&rown($safeeval,0);
+   } else { $tabledata='<pre>'; }
+
+    $r->print($tabledata);
+
     my $row;
     my $maxrow=&getmaxrow($safeeval);
-    $tabledata.=&rown($safeeval,'-');
-    $r->print($tabledata);
-    for ($row=0;$row<=$maxrow;$row++) {
-        $r->print(&rown($safeeval,$row));
+
+    my @sortby=();
+    my @sortidx=();
+    for ($row=1;$row<=$maxrow;$row++) {
+       $sortby[$row-1]=$safeeval->reval('$f{"A'.$row.'"}');
+       $sortidx[$row-1]=$row-1;
+    }
+    @sortidx=sort { $sortby[$a] cmp $sortby[$b]; } @sortidx;
+
+        my $what='Student';
+        if (&gettype($safeeval) eq 'assesscalc') {
+	    $what='Item';
+	} elsif (&gettype($safeeval) eq 'studentcalc') {
+            $what='Assessment';
+        }
+
+    my $n=0;
+    for ($row=0;$row<$maxrow;$row++) {
+     my $thisrow=&rown($safeeval,$sortidx[$row]+1);
+     if ($thisrow) {
+       if (($n/25==int($n/25)) && (!$ENV{'form.showcsv'})) {
+	$r->print("</table>\n<br>\n");
+        $r->rflush();
+        $r->print('<table border=2><tr><td>&nbsp;<td>'.$what.'</td>');
+        map {
+           $r->print('<td>'.$_.'</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');
+        $r->print('</tr>');
+       }
+       $n++;
+       $r->print($thisrow);
+      }
     }
-    $r->print('</table>');
+    $r->print($ENV{'form.showcsv'}?'</pre>':'</table>');
+}
+
+#
+# ----------------------------------------------- Read list of available sheets
+# 
+
+sub othersheets {
+    my ($safeeval,$stype)=@_;
+
+    my $cnum=&getcnum($safeeval);
+    my $cdom=&getcdom($safeeval);
+    my $chome=&getchome($safeeval);
+
+    my @alternatives=();
+    my $result=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum.':'.
+                                      $stype.'_spreadsheets',$chome);
+    if ($result!~/^error\:/) {
+	map {
+            $alternatives[$#alternatives+1]=
+            &Apache::lonnet::unescape((split(/\=/,$_))[0]);
+        } split(/\&/,$result);
+    } 
+    return @alternatives; 
 }
 
 #
@@ -749,10 +880,13 @@ sub readsheet {
 	my $sheetxml='';
        {
          my $fh;
-         if ($fh=Apache::File->new($includedir.
-                         '/default.'.&gettype($safeeval))) {
+         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>';
+	 }
        }
         my $parser=HTML::TokeParser->new(\$sheetxml);
         my $token;
@@ -826,8 +960,10 @@ sub writesheet {
 # ----------------------------------------------------------------- Write sheet
     my $sheetdata='';
     map {
+     unless ($f{$_} eq 'import') {
        $sheetdata.=&Apache::lonnet::escape($_).'='.
 	   &Apache::lonnet::escape($f{$_}).'&';
+     }
     } keys %f;
     $sheetdata=~s/\&$//;
     my $reply=&Apache::lonnet::reply('put:'.$cdom.':'.$cnum.':'.$fn.':'.
@@ -835,7 +971,8 @@ sub writesheet {
     if ($reply eq 'ok') {
           $reply=&Apache::lonnet::reply('put:'.$cdom.':'.$cnum.':'.
               $stype.'_spreadsheets:'.
-              &Apache::lonnet::escape($fn).'='.$ENV{'user.name'},
+              &Apache::lonnet::escape($fn).'='.$ENV{'user.name'}.'@'.
+                                               $ENV{'user.domain'},
               $chome);
           if ($reply eq 'ok') {
               if ($makedef) { 
@@ -893,7 +1030,14 @@ sub tmpread {
             $fo{$name}=$value;
         }
     }
-    if ($nfield) { $fo{$nfield}=$nform; }
+    if ($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}=$nform; }
+    }
     &setformulas($safeeval,%fo);
 }
 
@@ -921,7 +1065,7 @@ sub parmval {
 # ----------------------------------------------------- Cascading lookup scheme
        my $rwhat=$what;
        $what=~s/^parameter\_//;
-       $what=~s/\_/\./;
+       $what=~s/\_([^\_]+)$/\.$1/;
 
        my $symbparm=$symb.'.'.$what;
        my $mapparm=$mapname.'___(all).'.$what;
@@ -1012,17 +1156,36 @@ sub updateclasssheet {
                 my ($sname,$sdom)=split(/\:/,$name);
                 my $ssec=&Apache::lonnet::usection($sdom,$sname,$cid);
                 if ($ssec==-1) {
+		   unless ($ENV{'form.showcsv'}) {
                     $rowlabel='<font color=red>Data not available: '.$name.
 			      '</font>';
+		   } else {
+		       $rowlabel='ERROR","'.$name.
+                                 '","Data not available","","","';
+                   }
                 } 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>';
+		   unless ($ENV{'form.showcsv'}) {
+                    $rowlabel='<a href="/adm/studentcalc?uname='.$sname.
+                              '&udom='.$sdom.'">'.
+                              $ssec.'&nbsp;'.$reply{$sname}.'<br>';
                     map {
                         $rowlabel.=&Apache::lonnet::unescape($_).' ';
                     } split(/\&/,$reply);
+                    $rowlabel.='</a>';
+		   } else {
+		    $rowlabel=$ssec.'","'.$reply{$sname}.'"';
+                    my $ncount=0;
+                    map {
+                        $rowlabel.=',"'.&Apache::lonnet::unescape($_).'"';
+                        $ncount++;
+                    } split(/\&/,$reply);
+                    unless ($ncount==4) { $rowlabel.=',""'; }
+                    $rowlabel=~s/\"$//;
+		   }
                 }
 		$currentlist{&Apache::lonnet::unescape($name)}=$rowlabel;
             }
@@ -1081,8 +1244,26 @@ sub updatestudentassesssheet {
                        &GDBM_READER,0640)) {
 # --------------------------------------------------------- Get all assessments
 
-	my %allkeys=();
-        my %allassess=();
+	my %allkeys=('timestamp' => 
+                     'Timestamp of Last Transaction<br>timestamp');
+
+        my $adduserstr='';
+        if ((&getuname($safeeval) ne $ENV{'user.name'}) ||
+            (&getudom($safeeval) ne $ENV{'user.domain'})) {
+            $adduserstr='&uname='.&getuname($safeeval).
+		'&udom='.&getudom($safeeval);
+        }
+
+        my %allassess=('_feedback' =>
+	              '<a href="/adm/assesscalc?usymb=_feedback'.$adduserstr.
+                       '">Feedback</a>',
+                       '_evaluation' =>
+	              '<a href="/adm/assesscalc?usymb=_evaluation'.$adduserstr.
+                       '">Evaluation</a>',
+                       '_tutoring' =>
+	              '<a href="/adm/assesscalc?usymb=_tutoring'.$adduserstr.
+                       '">Tutoring</a>'
+        );
 
         map {
 	    if ($_=~/^src\_(\d+)\.(\d+)$/) {
@@ -1096,7 +1277,8 @@ sub updatestudentassesssheet {
 			    '___'.$resid.'___'.
 			    &Apache::lonnet::declutter($srcf);
 		 $allassess{$symb}=
-    '<a href="/adm/assesscalc?usymb='.$symb.'">'.$bighash{'title_'.$id}.'</a>';
+	            '<a href="/adm/assesscalc?usymb='.$symb.$adduserstr.'">'.
+                     $bighash{'title_'.$id}.'</a>';
                  if ($stype eq 'assesscalc') {
                    map {
                        if (($_=~/^stores\_(.*)/) || ($_=~/^parameter\_(.*)/)) {
@@ -1149,10 +1331,14 @@ sub updatestudentassesssheet {
 	map {
 	    if ($_=~/^A(\d+)/) {
                 $maxrow=($1>$maxrow)?$1:$maxrow;
-                $existing{$f{$_}}=1;
-		unless ((defined($current{$f{$_}})) || (!$1)) {
+                my ($usy,$ufn)=split(/\_\_\&\&\&\_\_/,$f{$_});
+                $existing{$usy}=1;
+		unless ((defined($current{$usy})) || (!$1)) {
 		   $f{$_}='!!! Obsolete';
                    $changed=1;
+	        } elsif ($ufn) {
+		    $current{$usy}
+                       =~s/assesscalc\?usymb\=/assesscalc\?ufn\=$ufn\&usymb\=/;
                 }
             }
         } keys %f;
@@ -1202,9 +1388,10 @@ sub loadstudent {
 	if ($_=~/^A(\d+)/) {
 	   my $row=$1;
            unless (($f{$_}=~/^\!/) || ($row==0)) {
+	      my ($usy,$ufn)=split(/\_\_\&\&\&\_\_/,$f{$_});
 	      @assessdata=&exportsheet(&getuname($safeeval),
                                        &getudom($safeeval),
-                                       'assesscalc',$f{$_});
+                                       'assesscalc',$usy,$ufn);
               my $index=0;
               map {
                   if ($assessdata[$index]) {
@@ -1248,12 +1435,11 @@ sub loadcourse {
 <script>
     popwin=open('','popwin','width=400,height=100');
     popwin.document.writeln('<html><body bgcolor="#FFFFFF">'+
-      '<h1>Spreadsheet Calculation Progress</h1>'+
+      '<h3>Spreadsheet Calculation Progress</h3>'+
       '<form name=popremain>'+
       '<input type=text size=35 name=remaining value=Starting></form>'+
       '</body></html>');
     popwin.document.close();
-    popwin.close();
 </script>
 ENDPOP
     $r->rflush();
@@ -1291,7 +1477,7 @@ ENDPOP
     } keys %f;
     &setformulas($safeeval,%f);
     &setconstants($safeeval,%c);
-    $r->print('<script>popwin.close</script>');
+    $r->print('<script>popwin.close()</script>');
     $r->rflush(); 
 }
 
@@ -1393,6 +1579,18 @@ sub loadassessment {
 # ----------------- 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);
+    
+    map {
+        $thisassess{$_}=1;
+    } split(/\,/,&Apache::lonnet::metadata($srcf,'keys'));
+#
+# Load parameters
+#
    my %c=();
 
    if (tie(%parmhash,'GDBM_File',
@@ -1402,14 +1600,16 @@ sub loadassessment {
 	if ($_=~/^A/) {
             unless ($f{$_}=~/^\!/) {
   	       if ($f{$_}=~/^parameter/) {
+		if ($thisassess{$f{$_}}) {
                   my $val=&parmval($f{$_},$safeeval);
                   $c{$_}=$val;
                   $c{$f{$_}}=$val;
+	        }
 	       } else {
 		  my $key=$f{$_};
                   my $ckey=$key;
                   $key=~s/^stores\_/resource\./;
-                  $key=~s/\_/\./;
+                  $key=~s/\_/\./g;
  	          $c{$_}=$returnhash{$key};
                   $c{$ckey}=$returnhash{$key};
 	       }
@@ -1477,22 +1677,230 @@ sub loadrows {
     }
 }
 
+# ======================================================= Forced recalculation?
+
+sub checkthis {
+    my ($keyname,$time)=@_;
+    return ($time<$expiredates{$keyname});
+}
+sub forcedrecalc {
+    my ($uname,$udom,$stype,$usymb)=@_;
+    my $key=$uname.':'.$udom.':'.$stype.':'.$usymb;
+    my $time=$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; 
+}
+
 # ============================================================== Export handler
 #
 # Non-interactive call from with program
 #
 
 sub exportsheet {
+ my ($uname,$udom,$stype,$usymb,$fn)=@_;
+ my @exportarr=();
+#
+# Check if cached
+#
+
+ my $key=$uname.':'.$udom.':'.$stype.':'.$usymb;
+ my $found='';
+
+ if ($oldsheets{$key}) {
+     map {
+         my ($name,$value)=split(/\_\_\_\=\_\_\_/,$_);
+         if ($name eq $fn) {
+	     $found=$value;
+         }
+     } split(/\_\_\_\&\_\_\_/,$oldsheets{$key});
+ }
+
+ unless ($found) {
+     &cachedssheets($uname,$udom,&Apache::lonnet::homeserver($uname,$udom));
+     if ($oldsheets{$key}) {
+        map {
+            my ($name,$value)=split(/\_\_\_\=\_\_\_/,$_);
+            if ($name eq $fn) {
+	        $found=$value;
+            }
+        } split(/\_\_\_\&\_\_\_/,$oldsheets{$key});
+     }
+ }
+#
+# Check if still valid
+#
+ if ($found) {
+     if (&forcedrecalc($uname,$udom,$stype,$usymb)) {
+	 $found='';
+     }
+ }
  
-    my ($uname,$udom,$stype,$usymb,$fn)=@_;
+ if ($found) {
+#
+# Return what was cached
+#
+     @exportarr=split(/\_\_\_\;\_\_\_/,$found);
+
+ } else {
+#
+# Not cached
+#        
+
     my $thissheet=&makenewsheet($uname,$udom,$stype,$usymb);
     &readsheet($thissheet,$fn);
     &updatesheet($thissheet);
     &loadrows($thissheet);
-    &calcsheet($thissheet);
-    return &exportdata($thissheet);
+    &calcsheet($thissheet); 
+    @exportarr=&exportdata($thissheet);
+#
+# Store now
+#
+    my $cid=$ENV{'request.course.id'}; 
+    my $current='';
+    if ($stype eq 'studentcalc') {
+       $current=&Apache::lonnet::reply('get:'.
+                                     $ENV{'course.'.$cid.'.domain'}.':'.
+                                     $ENV{'course.'.$cid.'.num'}.
+				     ':nohist_calculatedsheets:'.
+                                     &Apache::lonnet::escape($key),
+                                     $ENV{'course.'.$cid.'.home'});
+    } else {
+       $current=&Apache::lonnet::reply('get:'.
+                                     &getudom($thissheet).':'.
+                                     &getuname($thissheet).
+				     ':nohist_calculatedsheets_'.
+                                     $ENV{'request.course.id'}.':'.
+                                     &Apache::lonnet::escape($key),
+                                     &getuhome($thissheet));
+
+    }
+    my %currentlystored=();
+    unless ($current=~/^error\:/) {
+       map {
+           my ($name,$value)=split(/\_\_\_\=\_\_\_/,$_);
+           $currentlystored{$name}=$value;
+       } split(/\_\_\_\&\_\_\_/,&Apache::lonnet::unescape($current));
+    }
+    $currentlystored{$fn}=join('___;___',@exportarr);
+
+    my $newstore='';
+    map {
+        if ($newstore) { $newstore.='___&___'; }
+        $newstore.=$_.'___=___'.$currentlystored{$_};
+    } keys %currentlystored;
+    my $now=time;
+    if ($stype eq 'studentcalc') {
+       &Apache::lonnet::reply('put:'.
+                         $ENV{'course.'.$cid.'.domain'}.':'.
+                         $ENV{'course.'.$cid.'.num'}.
+			 ':nohist_calculatedsheets:'.
+                         &Apache::lonnet::escape($key).'='.
+			 &Apache::lonnet::escape($newstore).'&'.
+                         &Apache::lonnet::escape($key).'.time='.$now,
+                         $ENV{'course.'.$cid.'.home'});
+   } else {
+       &Apache::lonnet::reply('put:'.
+                         &getudom($thissheet).':'.
+                         &getuname($thissheet).
+			 ':nohist_calculatedsheets_'.
+                         $ENV{'request.course.id'}.':'.
+                         &Apache::lonnet::escape($key).'='.
+			 &Apache::lonnet::escape($newstore).'&'.
+                         &Apache::lonnet::escape($key).'.time='.$now,
+                         &getuhome($thissheet));
+   }
+ }
+ return @exportarr;
+}
+# ============================================================ Expiration Dates
+#
+# Load previously cached student spreadsheets for this course
+#
+
+sub expirationdates {
+    undef %expiredates;
+    my $cid=$ENV{'request.course.id'};
+    my $reply=&Apache::lonnet::reply('dump:'.
+				     $ENV{'course.'.$cid.'.domain'}.':'.
+                                     $ENV{'course.'.$cid.'.num'}.
+				     ':nohist_expirationdates',
+                                     $ENV{'course.'.$cid.'.home'});
+    unless ($reply=~/^error\:/) {
+	map {
+            my ($name,$value)=split(/\=/,$_);
+            $expiredates{&Apache::lonnet::unescape($name)}
+                        =&Apache::lonnet::unescape($value);
+        } split(/\&/,$reply);
+    }
+}
+
+# ===================================================== Calculated sheets cache
+#
+# Load previously cached student spreadsheets for this course
+#
+
+sub cachedcsheets {
+    my $cid=$ENV{'request.course.id'};
+    my $reply=&Apache::lonnet::reply('dump:'.
+				     $ENV{'course.'.$cid.'.domain'}.':'.
+                                     $ENV{'course.'.$cid.'.num'}.
+				     ':nohist_calculatedsheets',
+                                     $ENV{'course.'.$cid.'.home'});
+    unless ($reply=~/^error\:/) {
+	map {
+            my ($name,$value)=split(/\=/,$_);
+            $oldsheets{&Apache::lonnet::unescape($name)}
+                      =&Apache::lonnet::unescape($value);
+        } split(/\&/,$reply);
+    }
+}
+
+# ===================================================== Calculated sheets cache
+#
+# Load previously cached assessment spreadsheets for this student
+#
+
+sub cachedssheets {
+  my ($sname,$sdom,$shome)=@_;
+  unless (($loadedcaches{$sname.'_'.$sdom}) || ($shome eq 'no_host')) {
+    my $cid=$ENV{'request.course.id'};
+    my $reply=&Apache::lonnet::reply('dump:'.$sdom.':'.$sname.
+			             ':nohist_calculatedsheets_'.
+                                      $ENV{'request.course.id'},
+                                     $shome);
+    unless ($reply=~/^error\:/) {
+	map {
+            my ($name,$value)=split(/\=/,$_);
+            $oldsheets{&Apache::lonnet::unescape($name)}
+                      =&Apache::lonnet::unescape($value);
+        } split(/\&/,$reply);
+    }
+    $loadedcaches{$sname.'_'.$sdom}=1;
+  }
 }
 
+# ===================================================== Calculated sheets cache
+#
+# Load previously cached assessment spreadsheets for this student
+#
+
 # ================================================================ Main handler
 #
 # Interactive call to screen
@@ -1532,6 +1940,14 @@ $tmpdir=$r->dir_config('lonDaemons').'/t
        }
     } (split(/&/,$ENV{'QUERY_STRING'}));
 
+    if (($ENV{'form.usymb'}=~/^\_(\w+)/) && (!$ENV{'form.ufn'})) {
+	$ENV{'form.ufn'}='default_'.$1;
+    }
+
+# -------------------------------------- Interactive loading of specific sheet?
+    if (($ENV{'form.load'}) && ($ENV{'form.loadthissheet'} ne 'Default')) {
+	$ENV{'form.ufn'}=$ENV{'form.loadthissheet'};
+    }
 # ------------------------------------------- Nothing there? Must be login user
 
     my $aname;
@@ -1567,6 +1983,12 @@ $tmpdir=$r->dir_config('lonDaemons').'/t
         }
     }
 
+    function changesheet(cn) {
+	document.sheet.unewfield.value=cn;
+        document.sheet.unewformula.value='changesheet';
+        document.sheet.submit();
+    }
+
 </script>
 ENDSCRIPT
     $r->print('</head><body bgcolor="#FFFFFF">'.
@@ -1583,6 +2005,18 @@ ENDSCRIPT
 
     $r->rflush();
 
+# ---------------------------------------------------------------- Full recalc?
+
+
+    if ($ENV{'form.forcerecalc'}) {
+	$r->print('<h4>Completely Recalculating Sheet ...</h4>');
+        undef %spreadsheets;
+        undef %courserdatas;
+        undef %userrdatas;
+        undef %defaultsheets;
+        undef %updatedata;
+   }
+ 
 # ---------------------------------------- Read new sheet or modified worksheet
 
     $r->uri=~/\/(\w+)$/;
@@ -1623,29 +2057,40 @@ ENDSCRIPT
 # ---------------------------------------------------------------- Course title
 
     $r->print('<h1>'.
-            $ENV{'course.'.$ENV{'request.course.id'}.'.description'}.'</h1>');
-
+            $ENV{'course.'.$ENV{'request.course.id'}.'.description'}.
+             '</h1><h3>'.localtime().'</h3>');
 
-# ---------------------------------------------------- See if something to save
+# ---------------------------------------------------- See if user can see this
 
-    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,$ENV{'form.makedefufn'}).'<p>');
-	}
+    if ((&gettype($asheet) eq 'classcalc') || 
+        (&getuname($asheet) ne $ENV{'user.name'}) ||
+        (&getudom($asheet) ne $ENV{'user.domain'})) {
+        unless (&Apache::lonnet::allowed('vgr',&getcid($asheet))) {
+	    $r->print(
+           '<h1>Access Permission Denied</h1></form></body></html>');
+            return OK;
+        }
     }
 
-# ------------------------------------------------ Write the modified worksheet
+# ---------------------------------------------------------- Additional options
 
-   $r->print('<b>Current sheet:</b> '.&getfilename($asheet).'<p>');
-
-   &tmpwrite($asheet);
+    $r->print(
+ '<input type=submit name=forcerecalc value="Completely Recalculate Sheet"><p>'
+		 );
+    if (&gettype($asheet) eq 'assesscalc') {
+       $r->print ('<p><font size=+2><a href="/adm/studentcalc?uname='.
+                                               &getuname($asheet).
+                                               '&udom='.&getudom($asheet).
+                  '">Level up: Student Sheet</a></font><p>');
+    }
+    
+    if ((&gettype($asheet) eq 'studentcalc') && 
+        (&Apache::lonnet::allowed('vgr',&getcid($asheet)))) {
+       $r->print (
+                   '<p><font size=+2><a href="/adm/classcalc">'.
+                   'Level up: Course Sheet</a></font><p>');
+    }
+    
 
 # ----------------------------------------------------------------- Save dialog
 
@@ -1661,10 +2106,45 @@ ENDSCRIPT
 
     $r->print(&hiddenfield('ufn',&getfilename($asheet)));
 
+# ----------------------------------------------------------------- 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>');
+        map {
+	    $r->print('<option name="'.$_.'"');
+            if ($ENV{'form.ufn'} eq $_) {
+               $r->print(' selected');
+            }
+            $r->print('>'.$_.'</option>');
+        } &othersheets($asheet,&gettype($asheet));
+        $r->print('</select><p>');
+        if (&gettype($asheet) eq 'studentcalc') {
+	    &setothersheets($asheet,&othersheets($asheet,'assesscalc'));
+        }
+    }
+
+# --------------------------------------------------------------- Cached sheets
+
+    &expirationdates();
+
+    undef %oldsheets;
+    undef %loadedcaches;
+
+    if (&gettype($asheet) eq 'classcalc') {
+        $r->print("Loading previously calculated student sheets ...<br>\n");
+        $r->rflush();
+        &cachedcsheets();
+    } elsif (&gettype($asheet) eq 'studentcalc') {
+        $r->print("Loading previously calculated assessment sheets ...<br>\n");
+        $r->rflush();
+        &cachedssheets(&getuname($asheet),&getudom($asheet),
+                       &getuhome($asheet));
+    }
 
 # ----------------------------------------------------- Update sheet, load rows
 
-    $r->print("Loaded sheet, updating rows ...<br>\n");
+    $r->print("Loaded sheet(s), updating rows ...<br>\n");
     $r->rflush();
 
     &updatesheet($asheet);
@@ -1680,6 +2160,43 @@ ENDSCRIPT
     my $calcoutput=&calcsheet($asheet);
     $r->print('<h3><font color=red>'.$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'; }
+            $fname.='_'.&gettype($asheet);
+            &setfilename($asheet,$fname);
+            $ENV{'form.ufn'}=$fname;
+	    $r->print('<p>Saving spreadsheet: '.
+                         &writesheet($asheet,$ENV{'form.makedefufn'}).'<p>');
+	}
+    }
+
+# ------------------------------------------------ Write the modified worksheet
+
+   $r->print('<b>Current sheet:</b> '.&getfilename($asheet).'<p>');
+
+   &tmpwrite($asheet);
+
+    if (&gettype($asheet) eq 'studentcalc') {
+	$r->print('<br>Show rows with empty A column: ');
+    } else {
+        $r->print('<br>Show empty rows: ');
+    } 
+    $r->print('<input type=checkbox name=showall onClick="submit()"');
+    if ($ENV{'form.showall'}) { $r->print(' checked'); }
+    $r->print('>');
+    if (&gettype($asheet) eq 'classcalc') {
+       $r->print(
+   ' Output CSV format: <input type=checkbox name=showcsv onClick="submit()"');
+       if ($ENV{'form.showcsv'}) { $r->print(' checked'); }
+       $r->print('>');
+    }
+# ------------------------------------------------------------- Print out sheet
+
     &outsheet($r,$asheet);
     $r->print('</form></body></html>');
 
@@ -1696,19 +2213,3 @@ ENDSCRIPT
 
 1;
 __END__
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-