# The LearningOnline Network with CAPA
#
# $Id: lontrackstudent.pm,v 1.23 2007/02/13 01:44:02 albertel 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::lonmysql;
use Apache::lonnet;
use Apache::lonlocal;
use Time::HiRes;
use lib '/home/httpd/lib/perl/';
use LONCAPA;

my $num_records=500;

sub get_data {
    my ($r,$prog_state,$navmap,$mode) = @_;
    ##
    ## Compose the query
    &Apache::lonhtmlcommon::Update_PrgWin
        ($r,$prog_state,&mt('Composing Query'));
    #
    # Allow the other server to begin processing the data before we ask for it.
    sleep(5);
    #
    my $max_time = &get_max_time_in_db($r,$prog_state);
    if (defined($max_time)) {
        $r->print('<h3>'.&mt('Activity data compiled up to [_1]',
                             &Apache::lonlocal::locallocaltime($max_time)).
                  '</h3>'.&mt('While data is processed, periodically reload this page for more recent activity').'<br />');
        $r->rflush();
    } else {
        $r->print('<h3>'.&mt('Unable to retrieve any data.  Please reload this page and try again.').'</h3>');
        return;
    }
    my $query = &build_query($mode);
    ##
    ## Send it along
    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>'.
                  &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 < $maxtime)) {
        &Apache::lonhtmlcommon::Update_PrgWin
            ($r,$prog_state,&mt('Waiting up to [_1] seconds for results',
                                $starttime+$maxtime-time));
        sleep(1);
    }
    if (! -e $endfile) {
        $r->print('<h2>'.
                  &mt('Unable to retrieve data.').'</h2>');
        $r->print(&mt('Please try again in a few minutes.'));
        return;
    }
    $r->rflush();
    #
    &Apache::lonhtmlcommon::Update_PrgWin
        ($r,$prog_state,&mt('Parsing results'));
    #
    my $last = &output_results($r,$results_file,$navmap,$mode);
    my ($sname,$sdom) = ($mode=~/^student:(.*):(.*)$/);
    
    my ($text,$inc);
    if ( $last > 0 && (($last+1) >= $env{'form.start'}+$num_records) ) {
	$text = 'View more activity by this student';
	$inc  = $num_records;
	$r->print(&Apache::loncommon::track_student_link($text,$sname,$sdom,undef,
							 ($env{'form.start'}+$inc)
							 ));
	$r->print('<br />');
    }
    $text = 'Resubmit last request to check for newer data';
    $r->print(&Apache::loncommon::track_student_link($text,$sname,$sdom,undef,
						     $env{'form.start'}));

    &Apache::lonhtmlcommon::Update_PrgWin($r,$prog_state,&mt('Finished!'));
    return;
}

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 $prefix = $course.'_'.$domain.'_';
    #
    my %tables = 
        ( 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;
}

sub get_max_time_in_db {
    my ($r,$prog_state) = @_;
    my %table = &table_names();
    my $query = qq{SELECT MAX(time) FROM $table{'activity'} };
    #
    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;
    }
    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 < $maxtime)) {
        &Apache::lonhtmlcommon::Update_PrgWin
            ($r,$prog_state,&mt('Waiting up to [_1] seconds for results',
                                $starttime+$maxtime-time));
        sleep(1);
    }
    if (! -e $endfile) {
        $r->print('<h2>'.
                  &mt('Unable to retrieve data.').'</h2>');
        $r->print(&mt('Please try again in a few minutes.'));
        return undef;
    }
    $r->rflush();
    #
    &Apache::lonhtmlcommon::Update_PrgWin
        ($r,$prog_state,&mt('Parsing results'));
    #
    if (! open(TIMEDATA,$results_file)) {
        $r->print('<h2>'.&mt('Unable to read results file.').'</h2>'.
                  '<p>'.
                  &mt('This is a serious error and has been logged.  '.
                      'You should contact your system administrator '.
                      'to resolve this issue.').
                  '</p>');
        return;
    }
    #
    my $timestr = '';
    while (my $line = <TIMEDATA>) {
        chomp($line);
        $timestr = &unescape($line);
    }
    close(TIMEDATA);
    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 $prefix = $course.'_'.$domain.'_';
    my $start = ($env{'form.start'}+0);
    #
    my %table = &table_names();
    #
    my $query;
    if ($mode eq 'full_class') {
        $query = qq{
        SELECT B.resource,A.time,C.student,A.action,E.machine,A.action_values 
            FROM $table{'activity'} AS A
            LEFT JOIN $table{'res'}      AS B ON B.res_id=A.res_id 
            LEFT JOIN $table{'student'}  AS C ON C.student_id=A.student_id 
            LEFT JOIN $table{'machine'}  AS E ON E.machine_id=A.machine_id
            ORDER BY A.time DESC
            LIMIT $start, $num_records
        };
    } elsif ($mode =~ /^student:(.*):(.*)$/) {
        my $student = $1.':'.$2;
        $query = qq{
            SELECT B.resource,A.time,A.action,E.machine,A.action_values 
                FROM $table{'activity'} AS A
                LEFT JOIN $table{'res'}      AS B ON B.res_id=A.res_id 
                LEFT JOIN $table{'student'}  AS C ON C.student_id=A.student_id 
                LEFT JOIN $table{'machine'}  AS E ON E.machine_id=A.machine_id
                WHERE C.student='$student'
                ORDER BY A.time DESC
                LIMIT $start, $num_records
            };
    }
    $query =~ s|$/||g;
    return $query;
}

###################################################################
###################################################################
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
        $r->print('<h2>'.&mt('So far, no data has been returned for your request').'</h2>');
        return -1;
    }
    if (! open(ACTIVITYDATA,$results_file)) {
        $r->print('<h2>'.&mt('Unable to read results file.').'</h2>'.
                  '<p>'.
                  &mt('This is a serious error and has been logged.  '.
                      'You should contact your system administrator '.
                      'to resolve this issue.').
                  '</p>');
        return -2;
    }
    ##
    ##
    my $tableheader;
    if ($mode eq 'full_class') { 
        $tableheader = 
            '<table><tr>'.
            '<th>'.&mt('Resource').'</th>'.
            '<th>'.&mt('Time').'</th>'.
            '<th>'.&mt('Student').'</th>'.
            '<th>'.&mt('Action').'</th>'.
 #           '<th>'.&mt('Originating Server').'</th>'.
            '<th align="left">'.&mt('Data').'</th>'.
            '</tr>'.$/;
    } elsif ($mode =~ /^student:(.*):(.*)$/) {
        $tableheader = 
            '<table><tr>'.
            '<th>'.&mt('Resource').'</th>'.
            '<th>'.&mt('Time').'</th>'.
            '<th>'.&mt('Action').'</th>'.
 #           '<th>'.&mt('Originating Server').'</th>'.
            '<th align="left">'.&mt('Data').'</th>'.
            '</tr>'.$/;
    }
    my $count = $env{'form.start'}-1;
    $r->rflush();
    ##
    ##
    while (my $line = <ACTIVITYDATA>) {
        # FIXME: does not pass symbs along :(
        chomp($line);
        $line = &unescape($line);
        if (++$count % 50 == 0) {
            if ($count != 0) { 
                $r->print('</table>'.$/);
                $r->rflush();
            }
            $r->print($tableheader);
        }
        my ($symb,$timestamp,$student,$action,$machine,$values);
        if ($mode eq 'full_class') {
            ($symb,$timestamp,$student,$action,$machine,$values) = split(',',$line,6);
        } else {
            ($symb,$timestamp,$action,$machine,$values) = split(',',$line,5);
        }
	foreach ($symb,$timestamp,$student,$action,$machine) {
	    $_=&unescape($_);
	}
        my ($title,$src);
        if ($symb =~ m:^/adm/:) {
            $title = $symb;
            $src = $symb;
        } else {
            my $nav_res = $navmap->getBySymb($symb);
            if (defined($nav_res)) {
                $title = $nav_res->compTitle();
                $src   = $nav_res->src();
            } else {
		$src = $symb;
		if ($src !~ m{/adm}) {
		    $title = &Apache::lonnet::gettitle($src);
		} elsif ($values =~ /^\s*$/ && 
		    (! defined($src) || $src =~ /^\s*$/)) {
                    next;
                } elsif ($values =~ /^\s*$/) {
                    $values = $src;
                } else {
                    $title = 'unable to retrieve title';
                    $src   = '/dev/null';
                }
            }
        }
        my %classes;
        my $class_count=0;
        if (! exists($classes{$symb})) {
            $classes{$symb} = $class_count++;
        }
        my $class = 'a';#.$classes{$symb};
        #
        if ($symb eq '/prtspool/') {
            $class = 'print';
            $title = 'retrieve printout';
        } elsif ($symb =~ m|^/adm/([^/]+)|) {
            $class = $1;
        } elsif ($symb =~ m|^/adm/|) {
            $class = 'adm';
        }
        if ($title eq 'unable to retrieve title') {
            $title =~ s/ /\&nbsp;/g;
            $class = 'warning';
        }
        if (! defined($title) || $title eq '') {
            $title = 'untitled';
            $class = 'warning';
        }
        # Clean up the values
	$values = &display_values($action,$values);
        #
        # Build the row for output
        my $tablerow = qq{<tr class="$class"><td>}.($count+1).qq{</td>};
        if ($src =~ m|^/adm/|) {
            $tablerow .= 
                '<td valign="top"><nobr>'.$title.'</nobr></td>';
        } else {
            $tablerow .= 
                '<td valign="top"><nobr>'.
                '<a href="'.$src.'">'.$title.'</a>'.
                '</nobr></td>';
        }
        $tablerow .= '<td valign="top"><nobr>'.$timestamp.'</nobr></td>';
        if ($mode eq 'full_class') {
            $tablerow.='<td valign="top">'.$student.'</td>';
        }
        $tablerow .= 
            '<td valign="top">'.$action.'</td>'.
#            '<td>'.$machine.'</td>'.
            '<td valign="top">'.$values.'</td>'.
            '</tr>';
        $r->print($tablerow.$/);
    }
    $r->print('</table>'.$/);### if (! $count % 50);
    close(ACTIVITYDATA);
    return $count;
}

###################################################################
###################################################################
sub display_values {
    my ($action,$values)=@_;
    my $result='<table>';
    if ($action eq 'CSTORE') {
	my %values=map {split('=',$_,-1)} split(/\&/,$values);
	foreach my $key (sort(keys(%values))) {
	    $result.='<tr><td align="right">'.
		&unescape($key).
		'</td><td>=</td><td align="left">'.
		&unescape($values{$key}).'</td></tr>';
	}
	$result.='</table>';
    } elsif ($action eq 'POST') {
	my %values;
        foreach my $pair (split(/\&/,$values)) {
            my ($key,$value) = split('=',&unescape($pair),-1);
            $values{$key} = $value;
        }
	foreach my $key (sort(keys(%values))) {
	    if ($key eq 'counter') { next; }
	    $result.='<tr><td align="right">'.$key.'</td>'.
		'<td>=</td><td align="left">'.$values{$key}.'</td></tr>';
	}
	$result.='</table>';
    } else {
	$result=&unescape($values)
    }
    return $result;
}
###################################################################
###################################################################
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 pick_student {
    my ($r) = @_;
    $r->print("Sorry, cannot display classlist at this time.  Come back another time.");
    return;
}

###################################################################
###################################################################
sub styles {
    return <<END;
<style type="text/css">
    tr.warning   { background-color: \#CCCCCC; }
    tr.chat      { background-color: \#CCCCCC; }
    tr.chatfetch { background-color: \#CCCCCC; }
    tr.navmaps   { background-color: \#CCCCCC; }
    tr.roles     { background-color: \#CCCCCC; }
    tr.flip      { background-color: \#CCCCCC; }
    tr.adm       { background-color: \#CCCCCC; }
    tr.print     { background-color: \#CCCCCC; }
    tr.printout  { background-color: \#CCCCCC; }
    tr.parmset   { background-color: \#CCCCCC; }
    tr.grades    { background-color: \#CCCCCC; }
</style>
END
} 

sub developer_centric_styles {
    return <<END;
<style type="text/css">
    tr.warning   { background-color: red; }
    tr.chat      { background-color: yellow; }
    tr.chatfetch { background-color: yellow; }
    tr.evaluate  { background-color: red; }
    tr.navmaps   { background-color: \#777777; }
    tr.roles     { background-color: \#999999; }
    tr.flip      { background-color: \#BBBBBB; }
    tr.adm       { background-color: green; }
    tr.print     { background-color: blue; }
    tr.parmset   { background-color: \#000088; }
    tr.printout  { background-color: blue; }
    tr.grades    { background-color: \#CCCCCC; }
</style>
END
}

###################################################################
###################################################################
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','start']);
    #
    # 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(&Apache::loncommon::start_page('Student Activity',&styles()).
              &Apache::lonhtmlcommon::breadcrumbs('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 $result = &request_data_update();
    #
    if (exists($env{'form.selected_student'})) {
        # For now, just show all the data, in the future allow selection of
        # a student
        my ($sname,$sdom) = split(':',$env{'form.selected_student'});
        if ($sname =~ /^$LONCAPA::username_re$/ 
	    && $sdom =~ /^$LONCAPA::domain_re$/) {
            $r->print('<h2>'.
                      &mt('Recent activity of [_1]:[_2]',$sname,$sdom).
                      '</h2>');
            $r->print('<p>'.&mt(<<END).'</p>');
Compiling student activity data can take a long time.
Your request continues to be processed while results are displayed.
END
            &get_data($r,\%prog_state,$navmap,
                      'student:'.$env{'form.selected_student'});
        } else {
            $r->print('<h2>'.&mt('Unable to process for [_1]:[_2]',
                                 $sname,$sdom).'</h2>');
        }
    } else {
        # For now, just show all the data instead of limiting it to one student
        &get_data($r,\%prog_state,$navmap,'full_class');
    }
    #
    &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,&mt('Done'));
    &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state);
    #
    $r->print("</form>\n");
    $r->print(&Apache::loncommon::end_page());
    $r->rflush();
    #
    return OK;
}

1;

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

=pod

=back

=cut

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

__END__