--- loncom/interface/lonstatistics.pm	2003/05/27 14:51:24	1.71
+++ loncom/interface/lonstatistics.pm	2003/10/03 15:34:58	1.78.2.1
@@ -1,6 +1,6 @@
 # The LearningOnline Network with CAPA
 #
-# $Id: lonstatistics.pm,v 1.71 2003/05/27 14:51:24 matthew Exp $
+# $Id: lonstatistics.pm,v 1.78.2.1 2003/10/03 15:34:58 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -300,9 +300,10 @@ sub PrepareClasslist {
     @Students = @TmpStudents;
     # 
     # Now deal with that current student thing....
-    if (exists($ENV{'form.StudentAssessmentStudent'})) {
+    $curr_student = undef;
+    if (exists($ENV{'form.SelectedStudent'})) {
         my ($current_uname,$current_dom) = 
-            split(':',$ENV{'form.StudentAssessmentStudent'});
+            split(':',$ENV{'form.SelectedStudent'});
         my $i;
         for ($i = 0; $i<=$#Students; $i++) {
             next if (($Students[$i]->{'username'} ne $current_uname) || 
@@ -310,15 +311,17 @@ sub PrepareClasslist {
             $curr_student = $Students[$i];
             last; # If we get here, we have our student.
         }
-        if ($i == 0) {
-            $prev_student = 'none';
-        } else {
-            $prev_student = $Students[$i-1];
-        }
-        if ($i == $#Students) {
-            $next_student = 'none';
-        } else {
-            $next_student = $Students[$i+1];
+        if (defined($curr_student)) {
+            if ($i == 0) {
+                $prev_student = undef;
+            } else {
+                $prev_student = $Students[$i-1];
+            }
+            if ($i == $#Students) {
+                $next_student = undef;
+            } else {
+                $next_student = $Students[$i+1];
+            }
         }
     }
     #
@@ -329,7 +332,7 @@ sub PrepareClasslist {
             @SelectedStudentData = ($ENV{'form.StudentData'});
         }
     } else {
-        @SelectedStudentData = ('fullname');
+        @SelectedStudentData = ('username');
     }
     foreach (@SelectedStudentData) {
         if ($_ eq 'all') {
@@ -377,11 +380,7 @@ selected student.
 #######################################################
 #######################################################
 sub current_student { 
-    if (defined($curr_student)) {
-        return $curr_student;
-    } else {
-        return 'All Students';
-    }
+    return $curr_student;
 }
 
 #######################################################
@@ -399,11 +398,7 @@ in the list of students.  Or something.
 #######################################################
 #######################################################
 sub previous_student { 
-    if (defined($prev_student)) {
-        return $prev_student;
-    } else {
-        return 'No Student Selected';
-    }
+    return $prev_student;
 }
 
 #######################################################
@@ -421,11 +416,7 @@ to be viewed.
 #######################################################
 #######################################################
 sub next_student { 
-    if (defined($next_student)) {
-        return $next_student;
-    } else {
-        return 'No Student Selected';
-    }
+    return $next_student;
 }
 
 #######################################################
@@ -528,10 +519,8 @@ sub PrepareCourseData {
         my $name_length = length($seq->{'title'});
         my $num_parts = $seq->{'num_assess_parts'};
         #
-        # The number of columns needed for the summation text: 
-        #    " 1/5" = 1+3 columns, " 10/99" = 1+5 columns
-        my $sum_length = 1+1+2*(length($num_parts));
-        my $num_col = $num_parts+$sum_length;
+        # Use 3 digits for each the sum and total, which means 7 total...
+        my $num_col = $num_parts+7;
         if ($num_col < $name_length) {
             $num_col = $name_length;
         }
@@ -816,6 +805,46 @@ sub DisplayClasslist {
     my @Fields = ('fullname','username','domain','id','section');
     #
     my $Str='';
+    if (! @Students) {
+        if ($SelectedSections[0] eq 'all') { 
+            if (lc($ENV{'form.Status'}) eq 'any') {
+                $Str .= '<h2>There are no students in the course.</h2>';
+            } elsif (lc($ENV{'form.Status'}) eq 'active') {
+                $Str .= '<h2>There are no currently enrolled students in '.
+                    'the course.</h2>';
+            } elsif (lc($ENV{'form.Status'}) eq 'expired') {
+                $Str .= '<h2>There are no previously enrolled '.
+                    'students in the course.</h2>';
+            }
+        } else { 
+            my $sections;
+            if (@SelectedSections == 1) {
+                $sections = 'section '.$SelectedSections[0];
+            } elsif (@SelectedSections > 2) {
+                $sections = 'sections '.join(', ',@SelectedSections);
+                $sections =~ s/, ([^,])*$/, and $1/;
+            } else {
+                $sections = 'sections '.join(' and ',@SelectedSections);
+            }
+            if (lc($ENV{'form.Status'}) eq 'any') {
+                $Str .= '<h2>There are no students in '.$sections.'.</h2>';
+            } elsif (lc($ENV{'form.Status'}) eq 'active') {
+                $Str .= '<h2>There are no currently enrolled students '.
+                    'in '.$sections.'.</h2>';
+            } elsif (lc($ENV{'form.Status'}) eq 'expired') {
+                $Str .= '<h2>There are no previously enrolled students '.
+                    'in '.$sections.'.</h2>';
+            }
+        }
+        $Str.= '<a href="/adm/statistics?reportSelected=student_assessment">'.
+            'Return to the chart.</a>';
+        $r->print($Str);
+        $r->rflush();
+        return;
+    }
+
+    # "Click" is asinine but it is probably not my place to change the world.
+    $Str .= '<h2>Click on a students name or username to view their chart</h2>';
     $Str .= '<table border="0"><tr><td bgcolor="#777777">'."\n";
     $Str .= '<table border="0" cellpadding="3"><tr bgcolor="#e6ffff">'."\n";
     foreach my $field (@Fields) {
@@ -836,10 +865,11 @@ sub DisplayClasslist {
         #
         foreach my $field (@Fields) {
             $Str .= '<td>';
-            if ($field eq 'fullname') {
+            if ($field eq 'fullname' || $field eq 'username') {
                 $Str .= '<a href="/adm/statistics?reportSelected=';
                 $Str .= &Apache::lonnet::escape('student_assessment');
-                $Str .= '&StudentAssessmentStudent=';
+                $Str .= '&sort='.&Apache::lonnet::escape($ENV{'form.sort'});
+                $Str .= '&SelectedStudent=';
                 $Str .= &Apache::lonnet::escape($sname).'">';
                 $Str .= $student->{$field}.'&nbsp';
                 $Str .= '</a>';
@@ -865,32 +895,27 @@ sub CreateMainMenu {
     #
     my $Str = '';
     #
-    $Str .= '<table border="0"><tbody><tr>'."\n";
-    $Str .= '<td></td>'."\n";
-    $Str .= '<td></td>'."\n";
-    $Str .= '<td align="center"><b>Select a Report</b></td>'."\n";
-    $Str .= '<tr>'."\n";
-    #
-    $Str .= '<td align="center">'.
-        '<input type="submit" name="Refresh" value="Update Display" />'.
-            "</td>\n";
-    $Str .= '<td align="center">'.
-        '<input type="submit" name="ClearCache" value="Clear Caches" />'.
-            "</td>\n";
-    #
-    $Str .= '<td align="center">';
-    $Str .= '<select name="reportSelected" >'."\n";
-    foreach (sort(keys(%$reports))) {
-        $Str .= '<option value="'.$_.'"';
-        if($current eq $_) {
-            $Str .= ' selected';
-        }
-        $Str .= '>'.$reports->{$_}.'</option>'."\n";
-    }
-    $Str .= '</select></td>'."\n";
-    #
-    $Str .= '</tr></tbody></table>'."\n";
-    $Str .= '<hr>'."\n";
+    $Str  = '<input type="hidden" name="reportSelected" value="'.$current.'">';
+#    $Str .= '<table border="0"><tbody><tr>'."\n";
+#    $Str .= '<td align="center"><b>Report:</b></td>'."\n";
+#    $Str .= '<td align="center">';
+#    $Str .= '<select name="reportSelected" '.
+#        'onchange="document.Statistics.submit()">'."\n";
+#    foreach (sort(keys(%$reports))) {
+#        $Str .= '<option value="'.$_.'"';
+#        if($current eq $_) {
+#            $Str .= ' selected';
+#        }
+#        $Str .= '>'.$reports->{$_}.'</option>'."\n";
+#    }
+#    $Str .= '</select></td>'."\n";
+#    #
+#    $Str .= '<td>'.('&nbsp;'x30).'</td>';
+#    $Str .= '<td align="center">'.
+#        '<input type="submit" name="ClearCache" value="Clear Caches" />'.
+#            "</td>\n";
+#    $Str .= '</tr></tbody></table>'."\n";
+#    $Str .= '<hr>'."\n";
     #
     return $Str;
 }
@@ -901,6 +926,8 @@ sub handler {
     my $r=shift;
     my $c = $r->connection();
     #
+    &Apache::loncoursedata::clear_internal_caches();
+    #
     # Check for overloading
     my $loaderror=&Apache::lonnet::overloaderror($r);
     if ($loaderror) { return $loaderror; }
@@ -940,7 +967,7 @@ sub handler {
     # Extract form elements from query string
     &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
                                             ['sort','reportSelected',
-                                             'StudentAssessmentStudent']);
+                                             'SelectedStudent']);
     if (! exists($ENV{'form.reportSelected'})) {
         $ENV{'form.reportSelected'} = 'student_assessment';
     }
@@ -982,8 +1009,8 @@ END
     my %reports = ('classlist'          => 'Class list',
                    'problem_statistics' => 'Problem Statistics',
                    'student_assessment' => 'Problem Status Chart',
-                   'percentage'         => 'Correct-problems Plot',
-                   'option_response'    => 'Option Response Analysis',
+#                   'percentage'         => 'Correct-problems Plot',
+#                   'option_response'    => 'Option Response Analysis',
 #                   'activitylog'        => 'Activity Log',
                    );
     $r->print(&CreateMainMenu($ENV{'form.status'},
@@ -1001,8 +1028,6 @@ END
         &Apache::lonstudentassessment::BuildStudentAssessmentPage($r,$c);
     } elsif($GoToPage eq 'DoDiffGraph' || $GoToPage eq 'PercentWrongGraph') {
 #        &Apache::lonproblemstatistics::BuildGraphicChart($r,$c);
-    } elsif($GoToPage eq 'classlist') {
-        &DisplayClasslist($r);
     } elsif($GoToPage eq 'Correct-problems Plot') {
 #	&Apache::lonpercentage::BuildPercentageGraph($r,$c);
     }