--- loncom/interface/lontrackstudent.pm	2004/12/22 22:54:59	1.11
+++ loncom/interface/lontrackstudent.pm	2005/04/07 06:56:23	1.15
@@ -1,6 +1,6 @@
 # The LearningOnline Network with CAPA
 #
-# $Id: lontrackstudent.pm,v 1.11 2004/12/22 22:54:59 albertel Exp $
+# $Id: lontrackstudent.pm,v 1.15 2005/04/07 06:56:23 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -44,10 +44,10 @@ package Apache::lontrackstudent;
 
 use strict;
 use Apache::Constants qw(:common :http);
-use Apache::lonnet();
+use Apache::lonmysql;
+use Apache::lonnet;
 use Apache::lonlocal;
 use Time::HiRes;
-use Time::Local;
 
 sub get_data {
     my ($r,$prog_state,$navmap,$mode) = @_;
@@ -72,7 +72,7 @@ sub get_data {
     my $query = &build_query($mode);
     ##
     ## Send it along
-    my $home = $ENV{'course.'.$ENV{'request.course.id'}.'.home'};
+    my $home = $env{'course.'.$env{'request.course.id'}.'.home'};
     my $reply=&Apache::lonnet::metadata_query($query,undef,undef,[$home]);
     if (ref($reply) ne 'HASH') {
         $r->print('<h2>'.
@@ -112,17 +112,17 @@ sub get_data {
 }
 
 sub table_names {
-    my $cid = $ENV{'request.course.id'};
-    my $domain = $ENV{'course.'.$cid.'.domain'};
-    my $home = $ENV{'course.'.$cid.'.home'};
-    my $course = $ENV{'course.'.$cid.'.num'};
+    my $cid = $env{'request.course.id'};
+    my $domain = $env{'course.'.$cid.'.domain'};
+    my $home = $env{'course.'.$cid.'.home'};
+    my $course = $env{'course.'.$cid.'.num'};
     my $prefix = $course.'_'.$domain.'_';
     #
     my %tables = 
-        ( student => $prefix.'students',
-          res     => $prefix.'resource',
-          machine => $prefix.'machine_table',
-          activity=> $prefix.'activity',
+        ( student =>&Apache::lonmysql::fix_table_name($prefix.'students'),
+          res     =>&Apache::lonmysql::fix_table_name($prefix.'resource'),
+          machine =>&Apache::lonmysql::fix_table_name($prefix.'machine_table'),
+          activity=>&Apache::lonmysql::fix_table_name($prefix.'activity'),
           );
     return %tables;
 }
@@ -132,7 +132,7 @@ sub get_max_time_in_db {
     my %table = &table_names();
     my $query = qq{SELECT MAX(time) FROM $table{'activity'} };
     #
-    my $home = $ENV{'course.'.$ENV{'request.course.id'}.'.home'};
+    my $home = $env{'course.'.$env{'request.course.id'}.'.home'};
     my $reply=&Apache::lonnet::metadata_query($query,undef,undef,[$home]);
     if (ref($reply) ne 'HASH') {
         return undef;
@@ -178,22 +178,15 @@ sub get_max_time_in_db {
         $timestr = &Apache::lonnet::unescape($line);
     }
     close(TIMEDATA);
-    my ($year,$month,$day,$hour,$min,$sec) = 
-        ($timestr =~ /^(\d+)-(\d+)-(\d+) (\d+):(\d+):(\d+)/);
-    $month -= 1; # Good old timelocal
-    my $max_time = undef;
-    if (eval("&timelocal($sec,$min,$hour,$day,$month,$year)")) {
-        $max_time = &timelocal($sec,$min,$hour,$day,$month,$year);
-    }
-    return $max_time;
+    return &Apache::lonmysql::unsqltime($timestr);
 }
 
 sub build_query {
     my ($mode) = @_;
-    my $cid = $ENV{'request.course.id'};
-    my $domain = $ENV{'course.'.$cid.'.domain'};
-    my $home = $ENV{'course.'.$cid.'.home'};
-    my $course = $ENV{'course.'.$cid.'.num'};
+    my $cid = $env{'request.course.id'};
+    my $domain = $env{'course.'.$cid.'.domain'};
+    my $home = $env{'course.'.$cid.'.home'};
+    my $course = $env{'course.'.$cid.'.num'};
     my $prefix = $course.'_'.$domain.'_';
     #
     my %table = &table_names();
@@ -232,6 +225,11 @@ sub output_results {
     my ($r,$results_file,$navmap,$mode) = @_;
     ##
     ##
+    if (! -s $results_file) {
+        # results file is empty, just let them know there is no data
+        $r->print('<h2>'.&mt('No data was returned for your request').'</h2>');
+        return;
+    }
     if (! open(ACTIVITYDATA,$results_file)) {
         $r->print('<h2>'.&mt('Unable to read results file.').'</h2>'.
                   '<p>'.
@@ -396,10 +394,10 @@ sub display_values {
 ###################################################################
 sub request_data_update {
     my $command = 'prepare activity log';
-    my $cid = $ENV{'request.course.id'};
-    my $domain = $ENV{'course.'.$cid.'.domain'};
-    my $home = $ENV{'course.'.$cid.'.home'};
-    my $course = $ENV{'course.'.$cid.'.num'};
+    my $cid = $env{'request.course.id'};
+    my $domain = $env{'course.'.$cid.'.domain'};
+    my $home = $env{'course.'.$cid.'.home'};
+    my $course = $env{'course.'.$cid.'.num'};
 #    &Apache::lonnet::logthis($command.' '.$course.' '.$domain.' '.$home);
     my $result = &Apache::lonnet::metadata_query($command,$course,$domain,
                                                  [$home]);
@@ -465,18 +463,18 @@ sub handler {
     $loaderror=
         &Apache::lonnet::overloaderror
         ($r,
-         $ENV{'course.'.$ENV{'request.course.id'}.'.home'});
+         $env{'course.'.$env{'request.course.id'}.'.home'});
     if ($loaderror) { return $loaderror; }
     #
     # Check for access
-    if (! &Apache::lonnet::allowed('vsa',$ENV{'request.course.id'})) {
-        $ENV{'user.error.msg'}=
+    if (! &Apache::lonnet::allowed('vsa',$env{'request.course.id'})) {
+        $env{'user.error.msg'}=
             $r->uri.":vsa:0:0:Cannot student activity for complete course";
         if (! 
             &Apache::lonnet::allowed('vsa',
-                                     $ENV{'request.course.id'}.'/'.
-                                     $ENV{'request.course.sec'})) {
-            $ENV{'user.error.msg'}=
+                                     $env{'request.course.id'}.'/'.
+                                     $env{'request.course.sec'})) {
+            $env{'user.error.msg'}=
                 $r->uri.":vsa:0:0:Cannot view student activity with given role";
             return HTTP_NOT_ACCEPTABLE;
         }
@@ -503,7 +501,8 @@ sub handler {
                                             bug=>'instructor interface'});
     #
     # Give the LON-CAPA page header
-    $r->print('<html><head>'.&styles.'<title>'.
+    my $html=&Apache::lonxml::xmlbegin();
+    $r->print($html.'<head>'.&styles().'<title>'.
               &mt('Student Activity').
               "</title></head>\n".
               &Apache::loncommon::bodytag('Student Activity').
@@ -526,14 +525,11 @@ sub handler {
         ($r,\%prog_state,&mt('Contacting course home server'));
     #
     my $result = &request_data_update();
-    if (ref($result) eq 'HASH') {
-        $result = join(' ',map { $_.'=>'.$result->{$_}; } keys(%$result));
-    }
     #
-    if (exists($ENV{'form.selected_student'})) {
+    if (exists($env{'form.selected_student'})) {
         # For now, just show all the data, in the future allow selection of
         # a student
-        my ($sname,$sdom) = split(':',$ENV{'form.selected_student'});
+        my ($sname,$sdom) = split(':',$env{'form.selected_student'});
         if ($sname =~ /^\w*$/ && $sdom =~ /^\w*$/) {
             $r->print('<h2>'.
                       &mt('Recent activity of [_1]@[_2]',$sname,$sdom).
@@ -543,7 +539,7 @@ Compiling student activity data can take
 It may be necessary to reload this page to get the most current information.
 END
             &get_data($r,\%prog_state,$navmap,
-                      'student:'.$ENV{'form.selected_student'});
+                      'student:'.$env{'form.selected_student'});
         } else {
             $r->print('<h2>'.&mt('Unable to process for [_1]@[_2]',
                                  $sname,$sdom).'</h2>');