# The LearningOnline Network with CAPA
#
# $Id: lontrackstudent.pm,v 1.2 2004/08/11 23:37:36 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/
#
###

=pod

=head1 NAME

lontrackstudent

=head1 SYNOPSIS

Track student progress through course materials

=over 4

=cut

package Apache::lontrackstudent;

use strict;
use Apache::Constants qw(:common :http);
use Apache::lonnet();
use Apache::lonlocal;
use Time::HiRes;

###################################################################
###################################################################
sub get_all_data {
    my ($r,$prog_state,$navmap) = @_;
    ##
    ## Compose the query
    &Apache::lonhtmlcommon::Update_PrgWin
        ($r,$prog_state,&mt('Composing Query'));
    #
    my $query;
    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 $student_table  = $prefix.'students';
    my $res_table      = $prefix.'resource';
    my $action_table   = $prefix.'actions';
    my $machine_table  = $prefix.'machine_table';
    my $activity_table = $prefix.'activity';
    #
    $query = qq{
        select B.resource,A.time,C.student,D.action,E.machine,A.action_values 
            FROM $activity_table AS A
            LEFT JOIN $res_table AS B ON B.res_id=A.res_id 
            LEFT JOIN $student_table  AS C ON C.student_id=A.student_id 
            LEFT JOIN $action_table   AS D ON D.action_id=A.action_id 
            LEFT JOIN $machine_table  AS E ON E.machine_id=A.machine_id
    };
    $query =~ s|$/||g;
    # &Apache::lonnet::logthis($query);
    ##
    ## Send it along
    my $reply=&Apache::lonnet::metadata_query($query,undef,undef,[$home]);
    if (ref($reply) ne 'HASH') {
        $r->print('<h2>'.
                  &mt('Error contacting home server for course: [_1]',
                      $reply).
                  '</h2>');
        return;
    }
    my $results_file = $r->dir_config('lonDaemons').'/tmp/'.$reply->{$home};
    my $endfile = $results_file.'.end';
    ##
    ## Check for the results
    &Apache::lonhtmlcommon::Update_PrgWin
        ($r,$prog_state,&mt('Waiting for results'));
    my $maxtime = 500;
    my $starttime = time;
    while (! -e $endfile && (time-$starttime < $maxtime)) {
        sleep(1);
        &Apache::lonhtmlcommon::Update_PrgWin
            ($r,$prog_state,&mt('Waiting for results'));
    }
    if (! -e $endfile) {
        $r->print('<h2>'.
                  &mt('Unable to retrieve data.').'</h2>');
        $r->print(&mt('Please try again in a few minutes.'));
        return;
    }
    &Apache::lonhtmlcommon::Update_PrgWin
        ($r,$prog_state,&mt('Parsing results'));
    if (! open(ACTIVITYDATA,$results_file)) {
        $r->print('<h2>'.
                  &mt('Unable to read results file.  This is a serious error and has been logged.  You should contact your system administrator to resolve this issue.  If you are the system administrator, I feel sorry for you.').
                  '</h2>');
        return;
    }
    my $tableheader = 
        '<table><tr>'.
        '<th>'.&mt('Resource').'</th>'.
        '<th>'.&mt('Time').'</th>'.
        '<th>'.&mt('Student').'</th>'.
        '<th>'.&mt('Action').'</th>'.
        '<th>'.&mt('Originating Server').'</th>'.
        '<th>'.&mt('Data').'</th>'.
        '</tr>'.$/;
    my $count =0;
    $r->print($tableheader);
    $r->rflush();
    while (my $line = <ACTIVITYDATA>) {
        $line = &Apache::lonnet::unescape($line);
        if (++$count % 50 == 0) {
            $r->print('</table>'.$/);
            $r->rflush();
            $r->print($tableheader);
        }
        my ($symb,$timestamp,$student,$action,$machine,$values) =
            map { &Apache::lonnet::unescape($_); } split(',',$line,6);
        my ($title,$src);
        if ($symb =~ m:^/(res|adm)/:) {
            $title = $symb;
            $src = $symb;
        } else {
            # We may need to add 'uploaded/' to the symb
            # 
            # Hey, guess what - navmaps->getBySymb 
            # does not work with uploaded resources/new style courses/something
            # The fact that our symbs do not have uploaded/ prepended to them
            # then they (most often but not always) should, is likely to be
            # a puzzle too.
            #my $nav_res = $navmap->getBySymb($symb);
            $title = 'resource title goes here'; # $nav_res->title();
            $src   = '/dev/null'; # $nav_res->src();
        }
        $r->print('<tr>'.
                  '<td>'.'<a href="'.$src.'">'.$title.'</a>'.'</td>'.
                  '<td><nobr>'.$timestamp.'</nobr></td>'.
                  '<td>'.$student.'</td>'.
                  '<td>'.$action.'</td>'.
                  '<td>'.$machine.'</td>'.
                  '<td>'.$values.'</td>'.'</tr>'.$/);
    }
    $r->print('</table>'.$/);
    close(ACTIVITYDATA);
    &Apache::lonhtmlcommon::Update_PrgWin
        ($r,$prog_state,&mt('Finished!'));
    return;
}

sub get_student_data {}
sub html_output_student_data {}
sub html_output_class_data {}

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'};
    &Apache::lonnet::logthis($command.' '.$course.' '.$domain.' '.$home);
    my $result = &Apache::lonnet::metadata_query($command,$course,$domain,
                                                 [$home]);
    return $result;
}

###################################################################
###################################################################


###################################################################
###################################################################
sub handler {
    my $r=shift;
    my $c = $r->connection();
    #
    # Check for overloading here and on the course home server
    my $loaderror=&Apache::lonnet::overloaderror($r);
    if ($loaderror) { return $loaderror; }
    $loaderror=
        &Apache::lonnet::overloaderror
        ($r,
         $ENV{'course.'.$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'}=
            $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'}=
                $r->uri.":vsa:0:0:Cannot view student activity with given role";
            return HTTP_NOT_ACCEPTABLE;
        }
    }
    #
    # Send the header
    &Apache::loncommon::no_cache($r);
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    if ($r->header_only) { return OK; }
    #
    # Extract form elements from query string
    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
                                            ['selected_student']);
    #
    # We will almost always need this...
    my $navmap = Apache::lonnavmaps::navmap->new();
    # 
    &Apache::lonhtmlcommon::clear_breadcrumbs();
    &Apache::lonhtmlcommon::add_breadcrumb({href=>'/adm/studentactivity',
                                            title=>'Student Activity',
                                            text =>'Student Activity',
                                            faq=>139,
                                            bug=>'instructor interface'});
    #
    # Give the LON-CAPA page header
    $r->print('<html><head><title>'.
              &mt('Student Activity').
              "</title></head>\n".
              &Apache::loncommon::bodytag('Student Activity').
              &Apache::lonhtmlcommon::breadcrumbs(undef,'Student Activity'));
    $r->rflush();
    #
    # Begin form output
    $r->print('<form name="trackstudent" method="post" action="/adm/trackstudent">');
    $r->print('<br />');
    $r->print('<div name="statusline">'.
              &mt('Status:[_1]',
                  '<input type="text" name="status" size="60" value="" />').
              '</div>');
    $r->rflush();
    my %prog_state=&Apache::lonhtmlcommon::Create_PrgWin
        ($r,&mt('Student Activity Retrieval'),
         &mt('Student Activity Retrieval'),undef,'inline',undef,
         'trackstudent','status');
    &Apache::lonhtmlcommon::Update_PrgWin
        ($r,\%prog_state,&mt('Contacting course home server'));
    #
    my $result = &request_data_update();
    if (ref($result) eq 'HASH') {
        $result = join(' ',map { $_.'=>'.$result->{$_}; } keys(%$result));
    }
    $r->print('<h2>'.$result.'</h2>');
    #
    if (! exists($ENV{'form.selected_student'})) {
        # Choose a student
        $r->print('If you worked here you would be done by now');
    } else {
        # Show a students activity
        $r->print('I would like to have something to show you but I do not.');
    }
    #
    &get_all_data($r,\%prog_state,$navmap);

#    &Apache::lonhtmlcommon::Update_PrgWin
#        ($r,\%prog_state,&mt('Done'));

    #
    $r->print("</form>\n");
    $r->print("</body>\n</html>\n");
    $r->rflush();
    #
    return OK;
}

1;

#######################################################
#######################################################

=pod

=back

=cut

#######################################################
#######################################################

__END__