--- loncom/homework/grades.pm	2011/11/14 03:08:01	1.663
+++ loncom/homework/grades.pm	2012/05/13 01:15:30	1.673
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # The LON-CAPA Grading handler
 #
-# $Id: grades.pm,v 1.663 2011/11/14 03:08:01 raeburn Exp $
+# $Id: grades.pm,v 1.673 2012/05/13 01:15:30 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -1524,17 +1524,15 @@ INNERJS
 
   function savedMsgHeader(Nmsg,usrctr,fullname) {
     var height = 70*Nmsg+250;
-    var scrollbar = "no";
     if (height > 600) {
 	height = 600;
-	scrollbar = "yes";
     }
     var xpos = (screen.width-600)/2;
     xpos = (xpos < 0) ? '0' : xpos;
     var ypos = (screen.height-height)/2-30;
     ypos = (ypos < 0) ? '0' : ypos;
 
-    pWin = window.open('', 'MessageCenter', 'resizable=yes,toolbar=no,location=no,scrollbars='+scrollbar+',screenx='+xpos+',screeny='+ypos+',width=700,height='+height);
+    pWin = window.open('', 'MessageCenter', 'resizable=yes,toolbar=no,location=no,scrollbars=yes,screenx='+xpos+',screeny='+ypos+',width=700,height='+height);
     pWin.focus();
     pDoc = pWin.document;
     pDoc.$docopen;
@@ -1829,14 +1827,27 @@ sub show_problem {
 	$companswer=~s|</form>||g;
 	$companswer=~s|name="submit"|name="would_have_been_submit"|g;
     }
+    my $renderheading = &mt('View of the problem');
+    my $answerheading = &mt('Correct answer');
+    if (($uname ne $env{'user.name'}) || ($udom ne $env{'user.domain'})) {
+        my $stu_fullname = $env{'form.fullname'};
+        if ($stu_fullname eq '') {
+            $stu_fullname = &Apache::loncommon::plainname($uname,$udom,'lastname');
+        }
+        my $forwhom = &nameUserString(undef,$stu_fullname,$uname,$udom);
+        if ($forwhom ne '') {
+            $renderheading = &mt('View of the problem for[_1]',$forwhom);
+            $answerheading = &mt('Correct answer for[_1]',$forwhom);
+        }
+    }
     $rendered=
         '<div class="LC_Box">'
-       .'<h3 class="LC_hcell">'.&mt('View of the problem').'</h3>'
+       .'<h3 class="LC_hcell">'.$renderheading.'</h3>'
        .$rendered
        .'</div>';
     $companswer=
         '<div class="LC_Box">'
-       .'<h3 class="LC_hcell">'.&mt('Correct answer').'</h3>'
+       .'<h3 class="LC_hcell">'.$answerheading.'</h3>'
        .$companswer
        .'</div>';
     my $result;
@@ -2508,6 +2519,183 @@ sub keywords_highlight {
     return $string;
 }
 
+# For Tasks provide a mechanism to display previous version for one specific student
+
+sub show_previous_task_version {
+    my ($request,$symb) = @_;
+    if ($symb eq '') {
+        $request->print("Unable to handle ambiguous references.");
+
+        return '';
+    }
+    my ($uname,$udom) = ($env{'form.student'},$env{'form.userdom'});
+    my $usec = &Apache::lonnet::getsection($udom,$uname,$env{'request.course.id'});
+    if (!&canview($usec)) {
+        $request->print('<span class="LC_warning">Unable to view previous version for requested student.('.
+                        $uname.':'.$udom.' in section '.$usec.' in course id '.
+                        $env{'request.course.id'}.')</span>');
+        return;
+    }
+    my $mode = 'both';
+    my $isTask = ($symb =~/\.task$/);
+    if ($isTask) {
+        if ($env{'form.previousversion'} =~ /^\d+$/) {
+            if ($env{'form.fullname'} eq '') {
+                $env{'form.fullname'} =
+                    &Apache::loncommon::plainname($uname,$udom,'lastname');
+            }
+            my $probtitle=&Apache::lonnet::gettitle($symb);
+            $request->print("\n\n".
+                            '<div class="LC_grade_show_user">'.
+                            '<h2>'.&nameUserString(undef,$env{'form.fullname'},$uname,$udom).
+                            '</h2>'."\n");
+            &Apache::lonxml::clear_problem_counter();
+            $request->print(&show_problem($request,$symb,$uname,$udom,1,1,$mode,
+                            {'previousversion' => $env{'form.previousversion'} }));
+            $request->print("\n</div>");
+        }
+    }
+    return;
+}
+
+sub choose_task_version_form {
+    my ($symb,$uname,$udom,$nomenu) = @_;
+    my $isTask = ($symb =~/\.task$/);
+    my ($current,$version,$result,$js,$displayed,$rowtitle);
+    if ($isTask) {
+        my %record = &Apache::lonnet::restore($symb,$env{'request.course.id'},
+                                              $udom,$uname);
+        if (($record{'resource.0.version'} eq '') ||
+            ($record{'resource.0.version'} < 2)) {
+            return ($record{'resource.0.version'},
+                    $record{'resource.0.version'},$result,$js);
+        } else {
+            $current = $record{'resource.0.version'};
+        }
+        if ($env{'form.previousversion'}) {
+            $displayed = $env{'form.previousversion'};
+            $rowtitle = &mt('Choose another version:')
+        } else {
+            $displayed = $current;
+            $rowtitle = &mt('Show earlier version:');
+        }
+        $result = '<div class="LC_left_float">';
+        my $list;
+        my $numversions = 0;
+        for (my $i=1; $i<=$record{'resource.0.version'}; $i++) {
+            if ($i == $current) {
+                if (!$env{'form.previousversion'} || $nomenu) {
+                    next;
+                } else {
+                    $list .= '<option value="'.$i.'">'.&mt('Current').'</option>'."\n";
+                    $numversions ++;
+                }
+            } elsif (defined($record{'resource.'.$i.'.0.status'})) {
+                unless ($i == $env{'form.previousversion'}) {
+                    $numversions ++;
+                }
+                $list .= '<option value="'.$i.'">'.$i.'</option>'."\n";
+            }
+        }
+        if ($numversions) {
+            $symb = &HTML::Entities::encode($symb,'<>"&');
+            $result .=
+                '<form name="getprev" method="post" action=""'.
+                ' onsubmit="return previousVersion('."'$uname','$udom','$symb','$displayed'".');">'.
+                &Apache::loncommon::start_data_table().
+                &Apache::loncommon::start_data_table_row().
+                '<th align="left">'.$rowtitle.'</th>'.
+                '<td><select name="version">'.
+                '<option>'.&mt('Select').'</option>'.
+                $list.
+                '</select></td>'.
+                &Apache::loncommon::end_data_table_row();
+            unless ($nomenu) {
+                $result .= &Apache::loncommon::start_data_table_row().
+                '<th align="left">'.&mt('Open in new window').'</th>'.
+                '<td><span class="LC_nobreak">'.
+                '<label><input type="radio" name="prevwin" value="1" />'.
+                &mt('Yes').'</label>'.
+                '<label><input type="radio" name="prevwin" value="0" checked="checked" />'.&mt('No').'</label>'.
+                '</span></td>'.
+                &Apache::loncommon::end_data_table_row();
+            }
+            $result .=
+                &Apache::loncommon::start_data_table_row().
+                '<th align="left">&nbsp;</th>'.
+                '<td>'.
+                '<input type="submit" name="prevsub" value="'.&mt('Display').'" />'.
+                '</td>'.
+                &Apache::loncommon::end_data_table_row().
+                &Apache::loncommon::end_data_table().
+                '</form>';
+            $js = &previous_display_javascript($nomenu,$current);
+        } elsif ($displayed && $nomenu) {
+            $result .= '<a href="javascript:window.close()">'.&mt('Close window').'</a>';
+        } else {
+            $result .= &mt('No previous versions to show for this student');
+        }
+        $result .= '</div>';
+    }
+    return ($current,$displayed,$result,$js);
+}
+
+sub previous_display_javascript {
+    my ($nomenu,$current) = @_;
+    my $js = <<"JSONE";
+<script type="text/javascript">
+// <![CDATA[
+function previousVersion(uname,udom,symb) {
+    var current = '$current';
+    var version = document.getprev.version.options[document.getprev.version.selectedIndex].value;
+    var prevstr = new RegExp("^\\\\d+\$");
+    if (!prevstr.test(version)) {
+        return false;
+    }
+    var url = '';
+    if (version == current) {
+        url = '/adm/grades?student='+uname+'&userdom='+udom+'&symb='+symb+'&command=submission';
+    } else {
+        url = '/adm/grades?student='+uname+'&userdom='+udom+'&symb='+symb+'&command=versionsub&previousversion='+version;
+    }
+JSONE
+    if ($nomenu) {
+        $js .= <<"JSTWO";
+    document.location.href = url;
+JSTWO
+    } else {
+        $js .= <<"JSTHREE";
+    var newwin = 0;
+    for (var i=0; i<document.getprev.prevwin.length; i++) {
+        if (document.getprev.prevwin[i].checked == true) {
+            newwin = document.getprev.prevwin[i].value;
+        }
+    }
+    if (newwin == 1) {
+        var options = 'height=600,width=800,resizable=yes,scrollbars=yes,location=no,menubar=no,toolbar=no';
+        url = url+'&inhibitmenu=yes';
+        if (typeof(previousWin) == 'undefined' || previousWin.closed) {
+            previousWin = window.open(url,'',options,1);
+        } else {
+            previousWin.location.href = url;
+        }
+        previousWin.focus();
+        return false;
+    } else {
+        document.location.href = url;
+        return false;
+    }
+JSTHREE
+    }
+    $js .= <<"ENDJS";
+    return false;
+}
+// ]]>
+</script>
+ENDJS
+
+}
+
 #--- Called from submission routine
 sub processHandGrade {
     my ($request,$symb) = @_;
@@ -4540,6 +4728,7 @@ sub displaySubByDates {
 	&Apache::loncommon::start_data_table_header_row().
 	'<th>'.&mt('Date/Time').'</th>'.
 	($isCODE?'<th>'.&mt('CODE').'</th>':'').
+        ($isTask?'<th>'.&mt('Version').'</th>':'').
 	'<th>'.&mt('Submission').'</th>'.
 	'<th>'.&mt('Status').'</th>'.
 	&Apache::loncommon::end_data_table_header_row();
@@ -4560,7 +4749,9 @@ sub displaySubByDates {
 	if (exists($$record{$version.':resource.0.version'})) {
 	    $interaction = $$record{$version.':resource.0.version'};
 	}
-
+        if ($isTask && $env{'form.previousversion'}) {
+            next unless ($interaction == $env{'form.previousversion'});
+        }
 	my $where = ($isTask ? "$version:resource.$interaction"
 		             : "$version:resource");
 	$studentTable.=&Apache::loncommon::start_data_table_row().
@@ -4568,6 +4759,9 @@ sub displaySubByDates {
 	if ($isCODE) {
 	    $studentTable.='<td>'.$record->{$version.':resource.CODE'}.'</td>';
 	}
+        if ($isTask) {
+            $studentTable.='<td>'.$interaction.'</td>';
+        }
 	my @versionKeys = split(/\:/,$$record{$version.':keys'});
 	my @displaySub = ();
 	foreach my $partid (@{$parts}) {
@@ -4587,7 +4781,7 @@ sub displaySubByDates {
                     
 		    my ($responseId)= ($isTask ? ($matchKey=~ /^resource\.(.*?)\.\Q$partid\E\.award$/)
 				               : ($matchKey=~ /^resource\.\Q$partid\E\.(.*?)\.submission$/));
-                    $displaySub[0].='<span class="LC_nobreak"';
+                    $displaySub[0].='<span class="LC_nobreak">';
                     $displaySub[0].='<b>'.&mt('Part: [_1]',$display_part).'</b>'
                                    .' <span class="LC_internal_info">'
                                    .'('.&mt('Response ID: [_1]',$responseId).')'
@@ -5412,6 +5606,7 @@ sub scantron_selectphase {
       LastNameLength - number of columns that the last name spans
       BubblesPerRow - number of bubbles available in each row used to 
                       bubble an answer. (If not specified, 10 assumed).
+
 =cut
 
 sub get_scantron_config {
@@ -6909,7 +7104,7 @@ sub scantron_get_correction {
        .&mt('The ID on the form is [_1]',
             "<tt>$$scan_record{'scantron.ID'}</tt>")
        .'<br />'
-       .&mt('The name on the paper is [_2], [_3]',
+       .&mt('The name on the paper is [_1], [_2]',
             $$scan_record{'scantron.LastName'},
             $$scan_record{'scantron.FirstName'})
        .'</p>';
@@ -7518,7 +7713,8 @@ sub scantron_get_maxbubble {
     my $response_number = 0;
     my $bubble_line     = 0;
     foreach my $resource (@resources) {
-        my ($analysis,$parts) = &scantron_partids_tograde($resource,$cid,$uname,$udom,undef,$bubbles_per_row);
+        my ($analysis,$parts) = &scantron_partids_tograde($resource,$cid,$uname,
+                                                          $udom,undef,$bubbles_per_row);
         if ((ref($analysis) eq 'HASH') && (ref($parts) eq 'ARRAY')) {
 	    foreach my $part_id (@{$parts}) {
                 my $lines;
@@ -7723,7 +7919,8 @@ sub scantron_process_students {
         }
         my ($analysis,$parts) =
             &scantron_partids_tograde($resource,$env{'request.course.id'},
-                                      $env{'user.name'},$env{'user.domain'},1,$bubbles_per_row);
+                                      $env{'user.name'},$env{'user.domain'},
+                                      1,$bubbles_per_row);
         $grader_partids_by_symb{$ressymb} = $parts;
         if (ref($analysis) eq 'HASH') {
             if (ref($analysis->{'parts_withrandomlist'}) eq 'ARRAY') {
@@ -7750,11 +7947,8 @@ SCANTRONFORM
     
     my $lock=&Apache::lonnet::set_lock(&mt('Grading bubblesheet exam'));
     my $count=&get_todo_count($scanlines,$scan_data);
-    my %prog_state=&Apache::lonhtmlcommon::Create_PrgWin($r,'Bubblesheet Status',
- 				    'Bubblesheet Progress',$count,
-				    'inline',undef,'scantronupload');
-    &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,
-					  'Processing first student');
+    my %prog_state=&Apache::lonhtmlcommon::Create_PrgWin($r,$count);
+    &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,'Processing first student');
     $r->print('<br />');
     my $start=&Time::HiRes::time();
     my $i=-1;
@@ -7786,8 +7980,7 @@ SCANTRONFORM
  	my $line=&scantron_get_line($scanlines,$scan_data,$i);
  	if ($line=~/^[\s\cz]*$/) { next; }
 	if ($started) {
-	    &Apache::lonhtmlcommon::Increment_PrgWin($r,\%prog_state,
-						     'last student');
+	    &Apache::lonhtmlcommon::Increment_PrgWin($r,\%prog_state,'last student');
 	}
 	$started=1;
  	my $scan_record=&scantron_parse_scanline($line,$i,\%scantron_config,
@@ -7817,7 +8010,8 @@ SCANTRONFORM
             if ((exists($grader_randomlists_by_symb{$ressymb})) ||
                 (ref($grader_partids_by_symb{$ressymb}) ne 'ARRAY')) {
                 my ($analysis,$parts) =
-                    &scantron_partids_tograde($resource,$env{'request.course.id'},$uname,$udom,undef,$bubbles_per_row);
+                    &scantron_partids_tograde($resource,$env{'request.course.id'},
+                                              $uname,$udom,undef,$bubbles_per_row);
                 $partids_by_symb{$ressymb} = $parts;
             } else {
                 $partids_by_symb{$ressymb} = $grader_partids_by_symb{$ressymb};
@@ -7946,7 +8140,8 @@ sub graders_resources_pass {
             my $ressymb = $resource->symb();
             my ($analysis,$parts) =
                 &scantron_partids_tograde($resource,$env{'request.course.id'},
-                                          $env{'user.name'},$env{'user.domain'},1,$bubbles_per_row);
+                                          $env{'user.name'},$env{'user.domain'},
+                                          1,$bubbles_per_row);
             $grader_partids_by_symb->{$ressymb} = $parts;
             if (ref($analysis) eq 'HASH') {
                 if (ref($analysis->{'parts_withrandomlist'}) eq 'ARRAY') {
@@ -8267,7 +8462,8 @@ sub checkscantron_results {
     my $map=$navmap->getResourceByUrl($sequence);
     my @resources=$navmap->retrieveResources($map,\&scantron_filter,1,0);
     my (%grader_partids_by_symb,%grader_randomlists_by_symb);
-    &graders_resources_pass(\@resources,\%grader_partids_by_symb,                             \%grader_randomlists_by_symb);
+    &graders_resources_pass(\@resources,\%grader_partids_by_symb,
+                            \%grader_randomlists_by_symb,$bubbles_per_row);
 
     my ($uname,$udom);
     my (%scandata,%lastname,%bylast);
@@ -8278,9 +8474,7 @@ sub checkscantron_results {
     my %completedstudents;
 
     my $count=&Apache::grades::get_todo_count($scanlines,$scan_data);
-    my %prog_state=&Apache::lonhtmlcommon::Create_PrgWin($r,'Bubblesheet/Submissions Comparison Status',
-                                    'Progress of Bubblesheet Data/Submission Records Comparison',$count,
-                                    'inline',undef,'checkscantron');
+    my %prog_state=&Apache::lonhtmlcommon::Create_PrgWin($r,$count);
     my ($username,$domain,$started);
     my $nav_error;
     &scantron_get_maxbubble(\$nav_error,\%scantron_config); # Need the bubble lines array to parse.
@@ -8289,8 +8483,7 @@ sub checkscantron_results {
         return '';
     }
 
-    &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,
-                                          'Processing first student');
+    &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,'Processing first student');
     my $start=&Time::HiRes::time();
     my $i=-1;
 
@@ -8300,8 +8493,7 @@ sub checkscantron_results {
         my $line=&Apache::grades::scantron_get_line($scanlines,$scan_data,$i);
         if ($line=~/^[\s\cz]*$/) { next; }
         if ($started) {
-            &Apache::lonhtmlcommon::Increment_PrgWin($r,\%prog_state,
-                                                     'last student');
+            &Apache::lonhtmlcommon::Increment_PrgWin($r,\%prog_state,'last student');
         }
         $started=1;
         my $scan_record=
@@ -8333,7 +8525,9 @@ sub checkscantron_results {
             if ((exists($grader_randomlists_by_symb{$ressymb})) ||
                 (ref($grader_partids_by_symb{$ressymb}) ne 'ARRAY')) {
                 (my $analysis,$parts) =
-                    &scantron_partids_tograde($resource,$env{'request.course.id'},$username,$domain,undef,$bubbles_per_row);
+                    &scantron_partids_tograde($resource,$env{'request.course.id'},
+                                              $username,$domain,undef,
+                                              $bubbles_per_row);
             } else {
                 $parts = $grader_partids_by_symb{$ressymb};
             }
@@ -8553,7 +8747,7 @@ sub letter_to_digits {
 
 sub href_symb_cmd {
     my ($symb,$cmd)=@_;
-    return '/adm/grades?symb='.&HTML::Entities::encode(&Apache::lonenc::check_encrypt($symb),'<>&"').'&command='.$cmd;
+    return '/adm/grades?symb='.&HTML::Entities::encode(&Apache::lonenc::check_encrypt($symb),'<>&"').'&amp;command='.$cmd;
 }
 
 sub grading_menu {
@@ -8913,7 +9107,8 @@ sub process_clicker {
     my $pincorrect=&mt("Percentage points for incorrect solution");
     my $selectform=&Apache::loncommon::select_form($env{'form.upfiletype'},'upfiletype',
 						   {'iclicker' => 'i>clicker',
-                                                    'interwrite' => 'interwrite PRS'});
+                                                    'interwrite' => 'interwrite PRS',
+                                                    'turning' => 'Turning Technologies'});
     $symb = &Apache::lonenc::check_encrypt($symb);
     $result.= &Apache::lonhtmlcommon::scripttag(<<ENDUPFORM);
 function sanitycheck() {
@@ -9087,6 +9282,9 @@ ENDHEADER
     if ($env{'form.upfiletype'} eq 'interwrite') {
         ($errormsg,$number)=&interwrite_eval(\@questiontitles,\%responses);
     }
+    if ($env{'form.upfiletype'} eq 'turning') {
+        ($errormsg,$number)=&turning_eval(\@questiontitles,\%responses);
+    }
     $result.='<br />'.&mt('Found [_1] question(s)',$number).'<br />'.
              '<input type="hidden" name="number" value="'.$number.'" />'.
              &mt('Awarding [_1] percent for correct and [_2] percent for incorrect responses',
@@ -9223,6 +9421,32 @@ sub interwrite_eval {
     return ($errormsg,$number);
 }
 
+sub turning_eval {
+    my ($questiontitles,$responses)=@_;
+    my $number=0;
+    my $errormsg='';
+    foreach my $line (split(/[\n\r]/,$env{'form.upfile'})) {
+        my %components=&Apache::loncommon::record_sep($line);
+        my @entries=map {$components{$_}} (sort(keys(%components)));
+        if ($#entries>$number) { $number=$#entries; }
+        my $id=$entries[0];
+        my @idresponses;
+        $id=~s/^[\#0]+//;
+        unless ($id) { next; }
+        for (my $idx=1;$idx<=$#entries;$idx++) {
+            $entries[$idx]=~s/\,/\;/g;
+            $entries[$idx]=~s/[^a-zA-Z0-9\.\*\-\+\;]+//g;
+            push(@idresponses,$entries[$idx]);
+        }
+        $$responses{$id}=join(',',@idresponses);
+    }
+    for (my $i=1; $i<=$number; $i++) {
+        $$questiontitles[$i]=&mt('Question [_1]',$i);
+    }
+    return ($errormsg,$number);
+}
+
+
 sub assign_clicker_grades {
     my ($r,$symb)=@_;
     if (!$symb) {return '';}
@@ -9360,13 +9584,17 @@ sub navmap_errormsg {
 }
 
 sub startpage {
-    my ($r,$symb,$crumbs,$onlyfolderflag,$nodisplayflag) = @_;
-    unshift(@$crumbs,{href=>&href_symb_cmd($symb,'gradingmenu'),text=>"Grading"});
-    $r->print(&Apache::loncommon::start_page('Grading',undef,
-                                          {'bread_crumbs' => $crumbs}));
-    &Apache::lonquickgrades::startGradeScreen($r,($env{'form.symb'}?'probgrading':'grading'));
+    my ($r,$symb,$crumbs,$onlyfolderflag,$nodisplayflag,$stuvcurrent,$stuvdisp,$nomenu,$js) = @_;
+    if ($nomenu) {
+        $r->print(&Apache::loncommon::start_page("Student's Version",$js,{'only_body' => '1'}));
+    } else {
+        unshift(@$crumbs,{href=>&href_symb_cmd($symb,'gradingmenu'),text=>"Grading"});
+        $r->print(&Apache::loncommon::start_page('Grading',$js,
+                                                 {'bread_crumbs' => $crumbs}));
+        &Apache::lonquickgrades::startGradeScreen($r,($env{'form.symb'}?'probgrading':'grading'));
+    }
     unless ($nodisplayflag) {
-       $r->print(&Apache::lonhtmlcommon::resource_info_box($symb,$onlyfolderflag));
+       $r->print(&Apache::lonhtmlcommon::resource_info_box($symb,$onlyfolderflag,$stuvcurrent,$stuvdisp));
     }
 }
 
@@ -9388,23 +9616,25 @@ sub handler {
     }
     &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'});
 
+# see what command we need to execute
+
+    my @commands=&Apache::loncommon::get_env_multiple('form.command');
+    my $command=$commands[0];
+
     &init_perm();
     if (!$env{'request.course.id'}) {
-        # Not in a course.
-        $env{'user.error.msg'}="/adm/grades::vgr:0:0:Cannot display grades page outside course context";
-        return HTTP_NOT_ACCEPTABLE;
+        unless ((&Apache::lonnet::allowed('usc',$env{'request.role.domain'})) &&
+                ($command =~ /^scantronupload/)) {
+            # Not in a course.
+            $env{'user.error.msg'}="/adm/grades::vgr:0:0:Cannot display grades page outside course context";
+            return HTTP_NOT_ACCEPTABLE;
+        }
     } elsif (!%perm) {
         $request->internal_redirect('/adm/quickgrades');
     }
     &Apache::loncommon::content_type($request,'text/html');
     $request->send_http_header;
 
-
-# see what command we need to execute
-
-    my @commands=&Apache::loncommon::get_env_multiple('form.command');
-    my $command=$commands[0];
-
     if ($#commands > 0) {
 	&Apache::lonnet::logthis("grades got multiple commands ".join(':',@commands));
     }
@@ -9427,8 +9657,29 @@ sub handler {
         &select_problem($request);
     } else {
 	if ($command eq 'submission' && $perm{'vgr'}) {
-            &startpage($request,$symb,[{href=>"", text=>"Student Submissions"}]);
+            my ($stuvcurrent,$stuvdisp,$versionform,$js);
+            if (($env{'form.student'} ne '') && ($env{'form.userdom'} ne '')) {
+                ($stuvcurrent,$stuvdisp,$versionform,$js) =
+                    &choose_task_version_form($symb,$env{'form.student'},
+                                              $env{'form.userdom'});
+            }
+            &startpage($request,$symb,[{href=>"", text=>"Student Submissions"}],undef,undef,$stuvcurrent,$stuvdisp,undef,$js);
+            if ($versionform) {
+                $request->print($versionform);
+            }
+            $request->print('<br clear="all" />');
 	    ($env{'form.student'} eq '' ? &listStudents($request,$symb) : &submission($request,0,0,$symb));
+        } elsif ($command eq 'versionsub' && $perm{'vgr'}) {
+            my ($stuvcurrent,$stuvdisp,$versionform,$js) =
+                &choose_task_version_form($symb,$env{'form.student'},
+                                          $env{'form.userdom'},
+                                          $env{'form.inhibitmenu'});
+            &startpage($request,$symb,[{href=>"", text=>"Previous Student Version"}],undef,undef,$stuvcurrent,$stuvdisp,$env{'form.inhibitmenu'},$js);
+            if ($versionform) {
+                $request->print($versionform);
+            }
+            $request->print('<br clear="all" />');
+            $request->print(&show_previous_task_version($request,$symb));
 	} elsif ($command eq 'pickStudentPage' && $perm{'vgr'}) {
             &startpage($request,$symb,[{href=>&href_symb_cmd($symb,'all_for_one'),text=>'Grade page/folder for one student'},
                                        {href=>'',text=>'Select student'}],1,1);
@@ -9566,8 +9817,11 @@ sub handler {
     if ($ssi_error) {
 	&ssi_print_error($request);
     }
-    &Apache::lonquickgrades::endGradeScreen($request);
-    $request->print(&Apache::loncommon::end_page());
+    if ($env{'form.inhibitmenu'}) {
+        $request->print(&Apache::loncommon::end_page());
+    } else {
+        &Apache::lonquickgrades::endGradeScreen($request);
+    }
     &reset_caches();
     return OK;
 }
@@ -9638,6 +9892,75 @@ ssi_with_retries()
 
 =over
 
+=head1 Routines to display previous version of a Task for a specific student
+
+Tasks are graded pass/fail. Students who have yet to pass a particular Task
+can receive another opportunity. Access to tasks is slot-based. If a slot
+requires a proctor to check-in the student, a new version of the Task will
+be created when the student is checked in to the new opportunity.
+
+If a particular student has tried two or more versions of a particular task,
+the submission screen provides a user with vgr privileges (e.g., a Course
+Coordinator) the ability to display a previous version worked on by the
+student.  By default, the current version is displayed. If a previous version
+has been selected for display, submission data are only shown that pertain
+to that particular version, and the interface to submit grades is not shown.
+
+=over 4
+
+=item show_previous_task_version()
+
+Displays a specified version of a student's Task, as the student sees it.
+
+Inputs: 2
+        request - request object
+        symb    - unique symb for current instance of resource
+
+Output: None.
+
+Side Effects: calls &show_problem() to print version of Task, with
+              version contained in form item: $env{'form.previousversion'}
+
+=item choose_task_version_form()
+
+Displays a web form used to select which version of a student's view of a
+Task should be displayed.  Either launches a pop-up window, or replaces
+content in existing pop-up, or replaces page in main window.
+
+Inputs: 4
+        symb    - unique symb for current instance of resource
+        uname   - username of student
+        udom    - domain of student
+        nomenu  - 1 if display is in a pop-up window, and hence no menu
+                  breadcrumbs etc., are displayed
+
+Output: 4
+        current   - student's current version
+        displayed - student's version being displayed
+        result    - scalar containing HTML for web form used to switch to
+                    a different version (or a link to close window, if pop-up).
+        js        - javascript for processing selection in versions web form
+
+Side Effects: None.
+
+=item previous_display_javascript()
+
+Inputs: 2
+        nomenu  - 1 if display is in a pop-up window, and hence no menu
+                  breadcrumbs etc., are displayed.
+        current - student's current version number.
+
+Output: 1
+        js      - javascript for processing selection in versions web form.
+
+Side Effects: None.
+
+=back
+
+=head1 Routines to process bubblesheet data.
+
+=over 4
+
 =item scantron_get_correction() : 
 
    Builds the interface screen to interact with the operator to fix a
@@ -9743,7 +10066,9 @@ ssi_with_retries()
 =item navmap_errormsg() :
 
    Returns HTML mark-up inside a <div></div> with a link to re-initialize the course.
-   Should be called whenever the request to instantiate a navmap object fails.  
+   Should be called whenever the request to instantiate a navmap object fails.
+
+=back
 
 =back