#
# $Id: lonwhatsnew.pm,v 1.35 2005/12/05 19:27:53 raeburn 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/
#


package Apache::lonwhatsnew;

use strict;
use lib qw(/home/httpd/lib/perl);
use Apache::lonnet;
use Apache::loncommon();
use Apache::lonhtmlcommon();
use Apache::lonlocal;
use Apache::loncoursedata();
use Apache::lonnavmaps();
use Apache::lonuserstate;
use Apache::Constants qw(:common :http);
use Time::Local;
use GDBM_File;

#----------------------------
# handler
#
#----------------------------

sub handler {
    my $r = shift;
    if ($r->header_only) {
        &Apache::loncommon::content_type($r,'text/html');
        $r->send_http_header;
        return OK;
    }
    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['command']);

    my $command;
    if ($env{'form.action'} eq 'reset') {
        $command = 'reset';
    } elsif ($env{'form.action'} eq 'update') {
        $command = 'update';
    } else {
        $command = $env{'form.command'};
    }

    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    $r->print(&display_header($command));
    if (! (($env{'request.course.fn'}) && (&Apache::lonnet::allowed('bre',$env{'request.course.id'})))) {
        # Not in a course, or not allowed to view action items
        $env{'user.error.msg'}="/adm/whatsnew:bre:0:0:Cannot display what's new screen";
        return HTTP_NOT_ACCEPTABLE;
    }

    &Apache::lonhtmlcommon::clear_breadcrumbs();
    if (($command eq 'chgthreshold') && (&Apache::lonnet::allowed('vgr',$env{'request.course.id'}))) {
        &Apache::lonhtmlcommon::add_breadcrumb
            ({href=>'/adm/whatsnew?command=threshold',
              text=>"Change thresholds"});
        $r->print(&Apache::lonhtmlcommon::breadcrumbs
            (undef,'Course Action Items','Course_Action_Items_Thresholds'));
    } else {
        &Apache::lonhtmlcommon::add_breadcrumb
            ({href=>'/adm/whatsnew',
              text=>"Display Action Items"});
        $r->print(&Apache::lonhtmlcommon::breadcrumbs
            (undef,'Course Action Items','Course_Action_Items_Display'));
    }
    &display_main_box($r,$command);
    return OK;
}

#------------------------------
# display_main_box
#
# Display all the elements within the main box
#------------------------------
                                                                                
sub display_main_box {
    my ($r,$command) = @_;
    my $domain=&Apache::loncommon::determinedomain();
    my $tabbg=&Apache::loncommon::designparm('coordinator.tabbg',$domain);
    $r->print('<table width="100%" border="0" cellpadding="5" cellspacing="0"><tr><td width="100%">');

    my %threshold_titles = (
                         av_attempts => 'Average number of attempts',
                         degdiff => 'Degree of difficulty',
                         numstudents => 'Total number of students with submissions',
    );
    my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
    my $crs = $env{'course.'.$env{'request.course.id'}.'.num'};

    if (($command eq 'chgthreshold') && (&Apache::lonnet::allowed('vgr',$env{'request.course.id'}))) {
        &display_config_box($r,$command,$tabbg,\%threshold_titles,$cdom,$crs);
    } else {
        &display_actions_box($r,$command,\%threshold_titles,$cdom,$crs);
    }
    $r->print(<<END_OF_BLOCK);
  </td>
 </tr>
</table><br />
</body>
</html>
END_OF_BLOCK
}

#-------------------------------
# display_header
#
# Display the header information and set
# up the HTML
#-------------------------------

sub display_header{
    my $html=&Apache::lonxml::xmlbegin();
    my $bodytag=&Apache::loncommon::bodytag('Course Action Items');
    return(<<ENDHEAD);
$html
<head>
<title>Course Action Items</title>
</head>
$bodytag
ENDHEAD
}

#-------------------------------
# display_actions_box
#
# Display the action items
#
#-------------------------------
                                                                                
sub display_actions_box() {
    my ($r,$command,$threshold_titles,$cdom,$crs) = @_;

    my $rowColor1 = "#ffffff";
    my $rowColor2 = "#eeeeee";

    my %unread = ();
    my %ungraded = ();
    my %bombed = ();
    my %triggered = ();
    my %changed = ();
    my @newmsgs = ();
    my @critmsgs = ();
    my @newdiscussions = ();
    my @tograde = ();
    my @bombs = ();
    my @warnings = ();
    my $msgcount = 0;
    my $critmsgcount = 0;

    my %res_title = ();
    my %show = ();
    my $needitems = 0;
    my $boxcount = 0;

    my $domain=&Apache::loncommon::determinedomain();
    my $function;
    if ($env{'request.role'}=~/^(cc|in|ta|ep)/) {
        $function='coordinator';
    }
    if ($env{'request.role'}=~/^(su|dc|ad|li)/) {
        $function='admin';
    }

    my %threshold = (
                      av_attempts => 2,
                      degdiff => 0.5,
                      numstudents => 2,
                     );

    my $pgbg=&Apache::loncommon::designparm($function.'.pgbg',$domain);
    my $tabbg=&Apache::loncommon::designparm($function.'.tabbg',$domain);

    unless ($env{'request.course.id'}) {
        $r->print('<br /><b><center>You are accessing an invalid course.</center></b><br /><br />');
        return;
    }

    my %checkallowed = (
             coursediscussion => &Apache::lonnet::allowed('pch',$env{'request.course.id'}),
             handgrading => &Apache::lonnet::allowed('mgr',$env{'request.course.id'}),
             abovethreshold => &Apache::lonnet::allowed('vgr',$env{'request.course.id'}),
             haserrors => &Apache::lonnet::allowed('opa',$env{'request.course.id'}),
             versionchanges => &Apache::lonnet::allowed('opa',$env{'request.course.id'}),
             coursenormalmail => 1,
             coursecritmail => 1,
    );

    my $timediff = 604800;
    my %display_settings = &get_display_settings();
    my $now = time;
    my %intervals = (
                   -1 => 'since start of course',
              2592000 => 'since last month',
               604800 => 'since last week',
                86400 => 'since yesterday',
    );
    my $interval = $intervals{$timediff};
    if ($timediff == -1) {
        $timediff = time;
    } 
    my $starttime = $now - $timediff;

    my %headings = &Apache::lonlocal::texthash(
                coursediscussion =>  'Unread course discussion posts',
                handgrading =>  'Problems requiring handgrading',
                haserrors => 'Problems with errors',
                versionchanges => 'Resources in course with version changes '.$interval,
                coursenormalmail => 'New course message',
                coursecritmail => 'New critical messages in course',
    );

    if ($checkallowed{'abovethreshold'}) {
        &get_curr_thresholds(\%threshold,$cdom,$crs);
    }

    $headings{'abovethreshold'} = &mt('Problems with av. attempts').' &ge; '.$threshold{'av_attempts'}.' '.&mt('or deg. difficulty').' &ge; '.$threshold{'degdiff'}.'<br /> '.&mt('and total number of students with submissions').' &ge; '.$threshold{'numstudents'};

    my @actionorder = ('handgrading','haserrors','abovethreshold','versionchanges','coursediscussion','coursenormalmail','coursecritmail');

    foreach my $key (keys(%checkallowed)) {
        $show{$key} = 0;
        if ($checkallowed{$key}) {
            unless ($display_settings{$key} eq 'off') {
                $show{$key} = 1;
            }
        }
    }

    foreach my $item (@actionorder) {
        unless ($item eq 'coursenormalmail' || $item eq 'coursecritmail') {
            if ($show{$item}) {
                $needitems = 1;
                last;
            }
        }
    }


    if (tie(my %bighash,'GDBM_File',$env{'request.course.fn'}.'.db',
	    &GDBM_READER(),0640)) {
	my $furl=$bighash{'first_url'};
	$r->print('<font size="+1"><a href="'.$furl.'">Go to first resource</a></font><a href="/adm/preferences?action=changecourseinit"></font><br />Change your preferences</a> to suppress display of this screen when accessing courses as Course Coordinator in the future.<br /><hr />');
	untie(%bighash);
    }

    my $result;

    if ($command eq 'reset') {
        $result = &process_reset($cdom,$crs);
    } elsif ($command eq 'update') {
        $result = &process_update($cdom,$crs,$threshold_titles);
    }
    if ($result) {
        $r->print($result.'<hr width="100%" />');
    }
    $r->rflush();

    if ($needitems) {
        &getitems(\%unread,\%ungraded,\%bombed,\%triggered,\%changed,\@newdiscussions,\@tograde,\@bombs,\@warnings,$rowColor1,$rowColor2,\%threshold,$cdom,$crs,\%res_title,\%show,$starttime);
    }
    if ($show{'coursenormalmail'}) {
        &getnormalmail(\@newmsgs);
    }
    if ($show{'coursecritmail'}) {
        &getcritmail(\@critmsgs);
    }

    $r->print(qq|<a href="javascript:changeAll('hide');">Hide All</a>&nbsp;&nbsp;<a href="javascript:changeAll('show');">Show All</a>|);

    $r->print('<br /><table border="0" width="100%" cellpadding="2" cellspacing="4"><tr><td align="left" valign="top" width="45%">');

    my $displayed = 0;
    my $totalboxes = keys(%checkallowed);
    my $halfway = int($totalboxes/2) + $totalboxes%2;
    foreach my $actionitem (@actionorder) {
        if ($checkallowed{$actionitem}) {
            if ($displayed == $halfway) {
                $r->print('</td><td width="5%">&nbsp;</td><td align="left" valign="top" width-"50%">');
            }
            &display_launcher($r,$actionitem,\%checkallowed,$tabbg,$rowColor1,$rowColor2,\%show,\%headings,\%res_title,\@tograde,\%ungraded,\@bombs,\%bombed,\%changed,\@warnings,\%triggered,\@newdiscussions,\%unread,$msgcount,\@newmsgs,$critmsgcount,\@critmsgs,$interval);
            $displayed ++; 
        }
    }
    $r->print('
           </table>
          </td>
         </tr>
        </table>
      </td>
    </tr>
   </table>');
}

#-------------------------------
# display_config_box
#
# Display the threshold setting screen 
#
#-------------------------------
                                                                                
sub display_config_box() {
    my ($r,$command,$tabbg,$threshold_titles,$cdom,$crs) = @_;
    my %threshold = ();
    my $rowColor1 = "#ffffff";
    my $rowColor2 = "#eeeeee";
    my $rowColor;

    my @thresholditems = ("av_attempts","degdiff","numstudents");
    my %threshold_titles = (
                         av_attempts => 'Average number of attempts',
                         degdiff => 'Degree of difficulty',
                         numstudents => 'Total number of students with submissions',
                         );
    &get_curr_thresholds(\%threshold,$cdom,$crs);

    $r->print('<br /><form name="thresholdform" method="post"><table border="0" cellpadding="2" cellspacing="4"><tr><td align="left" valign="top" width="45%">
           <table border="0" cellpadding="0" cellspacing="0" bgcolor="#000000">
            <tr>
             <td>
               <table border="0" cellpadding="1" cellspacing="1" bgcolor="#000000">
                <tr>
                <td bgcolor="#ffffff">
                 <table cellspacing="0" cellpadding="4" border="0">
     <tr bgcolor="'.$tabbg.'">
      <th>Threshold Name</th>
      <th>Current value</th>
      <th>Change?</th>
     </tr>');
    my $rowNum =0;
    foreach my $type (@thresholditems) {
        my $parameter = 'internal.threshold_'.$type;
# onchange is javascript to automatically check the 'Set' button.
        my $onchange = 'onFocus="javascript:window.document.forms'.
              "['thresholdform'].elements['".$parameter."_setparmval']".
              '.checked=true;"';
        if ($rowNum %2 == 1) {
            $rowColor = $rowColor1;
        } else {
            $rowColor = $rowColor2;
        }
        $r->print('
     <tr bgcolor="'.$rowColor.'">
      <td>'.$threshold_titles{$type}.'</td>
      <td>'.&Apache::lonhtmlcommon::textbox($parameter.'_value',
                                            $threshold{$type},
                                            10,$onchange).'</td>
      <td>'
           .&Apache::lonhtmlcommon::checkbox($parameter.'_setparmval').
      '</td>
     </tr>');
        $rowNum ++;
    }
    $r->print('</table></td></tr></table></td></tr></table>
           <br /><input type="submit" name="threshold" value="Make changes" />
                 <input type="hidden" name="action" value="update" />
               </form>');
}

sub display_launcher {
    my ($r,$action,$checkallowed,$tabbg,$rowColor1,$rowColor2,$show,
        $headings,$res_title,$tograde,$ungraded,$bombs,$bombed,$changed,
        $warnings,$triggered,$newdiscussions,$unread,$msgcount,$newmsgs,
                                       $critmsgcount,$critmsgs,$interval) = @_;

    if ($$checkallowed{$action}) {
        &start_box($r,$tabbg,$show,$headings,$action);
        if ($$show{$action}) {
            if ($action eq 'handgrading') {    # UNGRADED ITEMS
                &display_handgrade($r,$tograde,$rowColor1,$rowColor2,
                                                                    $ungraded);
            } elsif ($action eq 'haserrors') { # BOMBS
                &display_haserrors($r,$bombs,$rowColor1,$rowColor2,$bombed,
                                                                   $res_title);
            } elsif ($action eq 'versionchanges') { # VERSION CHANGES
                &display_versionchanges($r,$changed,$res_title,$rowColor1,
                                                         $rowColor2,$interval);

            } elsif ($action eq 'abovethreshold') { # DEGDIFF/AV. TRIES TRIGGERS
                &display_abovethreshold($r,$warnings,$triggered,$res_title,
                                                        $rowColor1,$rowColor2);
            } elsif ($action eq 'coursediscussion') { # UNREAD COURSE DISCUSSION
                &display_coursediscussion($r,$newdiscussions,$unread,
                                                                   $res_title);
            } elsif ($action eq 'coursenormalmail') { # NORMAL MESSAGES
                &display_coursenormalmail($r,$msgcount,$newmsgs,$rowColor1,
                                                                   $rowColor2);
            } elsif ($action eq 'coursecritmail') { # CRITICAL MESSAGES
                &display_coursecritmail($r,$critmsgcount,$critmsgs,$rowColor1,
                                                                   $rowColor2);
            }
        }
        &end_box($r);
    }
    return;
}

sub getitems {
    my ($unread,$ungraded,$bombed,$triggered,$changed,$newdiscussions,
        $tograde,$bombs,$warnings,$rowColor1,$rowColor2,$threshold,$cdom,$crs,
                                             $res_title,$show,$starttime) = @_;
    my $navmap = Apache::lonnavmaps::navmap->new();
    # force retrieve Resource to seed the part id cache we'll need it later
    my @allres=$navmap->retrieveResources(undef,sub {if ($_[0]->is_problem) { $_[0]->parts();} return 1;});
    my %lastreadtime;
    my %resourcetracker;

# Resource version changes
    if ($$show{'versionchanges'}) {
        &checkversions($cdom,$crs,$navmap,$changed,$starttime);
    }

    if ($$show{'coursediscussions'}) {   
        my %lastread = &Apache::lonnet::dump('nohist_'.
                        $env{'request.course.id'}.'_discuss',
                        $env{'user.domain'},$env{'user.name'},'lastread');
        foreach my $key (keys(%lastread)) {
            my $newkey = $key;
            $newkey =~ s/_lastread$//;
            $lastreadtime{$newkey} = $lastread{$key};
        }
    }
 
    if ($$show{'abovethreshold'}) {
        %resourcetracker =  &Apache::lonnet::dump('nohist_resourcetracker',
                                                                   $cdom,$crs);
    }

    my $warningnum = 0;
    foreach my $resource (@allres) {
        my $result = '';
        my $applies = 0;
        my $symb = $resource->symb();
        %{$$bombed{$symb}} = ();
        %{$$ungraded{$symb}} = ();
        %{$$triggered{$symb}} = ();
        $$triggered{$symb}{numparts} = 0;
        my $title = $resource->compTitle();
        $$res_title{$symb} = $title;
        my $ressymb = $resource->wrap_symb();

# Check for unread discussion postings
        if ($$show{'coursediscussion'}) {
            &check_discussions($cdom,$crs,$resource,$symb,$ressymb,$title,
                                       $newdiscussions,$unread,\%lastreadtime);
        }

# Check for ungraded problems
        if ($resource->is_problem()) {
            if ($$show{'handgrading'}) {
                &check_handgraded($resource,$symb,$title,$cdom,$crs,$ungraded,
                                                                     $tograde);
            }
        }

# Check for bombs
        if ($$show{'haserrors'}) {
            &check_bombed($resource,$symb,$title,$bombs,$bombed);
        }

# Maxtries and degree of difficulty for problem parts, unless handgradeable
        if ($$show{'abovethreshold'}) {  
            &check_thresholds($resource,$symb,\%resourcetracker,$triggered,
                       $threshold,$warnings,$warningnum,$rowColor1,$rowColor2);
        }

    }
}

sub check_discussions {
    my ($cdom,$crs,$resource,$symb,$ressymb,$title,$newdiscussions,$unread,
                                                           $lastreadtime) = @_;  
# Check for unread discussion postings
    if ($resource->hasDiscussion()) {
        my $prevread = 0;
        my $unreadcount = 0;
        %{$$unread{$ressymb}} = ();
        $$unread{$ressymb}{'title'} = $title;
        $$unread{$ressymb}{'symb'} = $symb;
        if (defined($$lastreadtime{$ressymb})) {
            $prevread = $$lastreadtime{$ressymb};
        }
        my %contrib = &Apache::lonnet::restore($ressymb,
                                         $env{'request.course.id'},$cdom,$crs);
        if ($contrib{'version'}) {
            for (my $id=1;$id<=$contrib{'version'};$id++) {
                unless (($contrib{'hidden'}=~/\.$id\./) || 
                        ($contrib{'deleted'}=~/\.$id\./)) {
                    if ($prevread <$contrib{$id.':timestamp'}) {
                        $$unread{$ressymb}{$unreadcount} = $id.': '.$contrib{$id.':subject'};
                        $unreadcount ++;
                    }
                }
            }
        }
        if ($unreadcount) { push(@{$newdiscussions}, $ressymb); }
    }
}

sub check_handgraded {
    my ($resource,$symb,$title,$cdom,$cnum,$ungraded,$tograde) = @_;
    if ($resource->is_problem()) {
        my ($map,$ind,$url)=&Apache::lonnet::decode_symb($symb);
        my $partlist=$resource->parts();
        my $handgradeable;
        foreach my $part (@$partlist) {
            if ($resource->handgrade($part) eq 'yes') {
                $handgradeable=1; last;
            }
        }
        if ($handgradeable) {
            my @ungraded = &Apache::bridgetask::get_queue_symb_status(
                                             'gradingqueue',$symb,$cdom,$cnum);
            if (@ungraded > 0) {
                $$ungraded{$symb}{count} = scalar(@ungraded);
                $$ungraded{$symb}{title} = $title;
                push(@{$tograde}, $symb);
            }
        }
    }
}

sub check_bombed {
    my ($resource,$symb,$title,$bombs,$bombed) = @_;
    if ($resource->getErrors()) {
        my $errors = $resource->getErrors();
        $errors =~ s/^,//;
        my @bombs = split(/,/, $errors);
        my $errorcount = scalar(@bombs);
        my $errorlink = '<a href="/adm/email?display='.
                        &Apache::lonnet::escape($bombs[0]).'">'.
                        $title.'</a>';
        $$bombed{$symb}{errorcount} = $errorcount;
        $$bombed{$symb}{errorlink} = $errorlink;
        push(@{$bombs}, $symb);
    }
}

sub check_thresholds {
    my ($resource,$symb,$resourcetracker,$triggered,$threshold,$warnings,
                                       $warningnum,$rowColor1,$rowColor2) = @_;
# Compile maxtries and degree of difficulty for problem parts, unless handgradeable
    my @parts = @{$resource->parts()};
    my %stats;
    my %lastreset = ();
    my $warning = 0;
    my $rowColor;
    foreach my $part (@parts) {
        if ($resource->handgrade($part) eq 'yes') {
            next;
        }
        %{$stats{$part}} = ();
        my ($attempts,$users,$corrects,$degdiff,$av_attempts);
        if (exists($$resourcetracker{$symb."\0".$part."\0attempts"})) {
            $attempts = $$resourcetracker{$symb."\0".$part."\0attempts"};
        }
        if (exists($$resourcetracker{$symb."\0".$part."\0users"})) {
            $users = $$resourcetracker{$symb."\0".$part."\0users"};
        }
        if (exists($$resourcetracker{$symb."\0".$part."\0correct"})) {
            $corrects = $$resourcetracker{$symb."\0".$part."\0correct"};
        }
        if ($attempts > 0) {
            $degdiff =  1 - ($corrects/$attempts);
            $degdiff = sprintf("%.2f",$degdiff);
        }
        if ($users > 0) {
            $av_attempts = $attempts/$users;
            $av_attempts = sprintf("%.2f",$av_attempts);
        }
        if ((($degdiff ne '' && $degdiff >= $$threshold{'degdiff'}) || ($av_attempts ne '' && $av_attempts >= $$threshold{'av_attempts'})) && ($users >= $$threshold{'numstudents'})) {
            $stats{$part}{degdiff} = $degdiff;
            $stats{$part}{attempts} = $av_attempts;
            $stats{$part}{users} = $users;
            $lastreset{$part} = $$resourcetracker{$symb."\0".$part."\0resettime"};
            if ($lastreset{$part}) {
                $lastreset{$part} = &Apache::lonnavmaps::timeToHumanString($lastreset{$part});
            }
            $warning = 1;
        }
    }
    if ($warning) {
        if ($warningnum %2 == 1) {
            $rowColor = $rowColor1;
        } else {
            $rowColor = $rowColor2;
        }
        $$triggered{$symb}{title} = $resource->title;
        foreach my $part (@parts) {
            if (exists($stats{$part}{users})) {
                my $resetname = 'reset_'.&Apache::lonnet::escape($symb."\0".$part);
                my $resettitle = 'title_'.&Apache::lonnet::escape($symb."\0".$part);
                if ($$triggered{$symb}{numparts}) {
                    $$triggered{$symb}{text} .= '<tr bgcolor="'.$rowColor.'">'."\n";
                }
                if (@parts > 1) {
                    $$triggered{$symb}{text} .= '
                     <td align="right"><small>part - '.$part.'<small></td>';
                } else {
                    $$triggered{$symb}{text} .= '
                     <td align="right"><small>single part</small></td>';
                }
                $$triggered{$symb}{text} .= '
                     <td align="right"><small>'.$stats{$part}{users}.'</small></td>
                     <td align="right"><small>'.$stats{$part}{attempts}.'</small></td>
                     <td align="right"><small>'.$stats{$part}{degdiff}.'</small></td>
                     <td align="right"><small>'.$lastreset{$part}.'</small></td>
                     <td align="right"><small><input type="checkbox" name="'.$resetname.'" /><input type="hidden" name="'.$resettitle.'" value="'.&Apache::lonnet::escape($$triggered{$symb}{title}).'" /></td>
                    </tr>';
                $$triggered{$symb}{numparts} ++;
            }
        }
        push(@{$warnings},$symb);
        $warningnum ++;
    }
}


sub get_curr_thresholds {
    my ($threshold,$cdom,$crs) = @_;
    my %coursesettings = &Apache::lonnet::dump('environment',
                                     $cdom,$crs,'internal.threshold');
    if (exists($coursesettings{'internal.threshold_av_attempts'})) {
        $$threshold{'av_attempts'} = $coursesettings{'internal.threshold_av_attempts'};
    }
    if (exists($coursesettings{'internal.threshold_degdiff'})) {
        $$threshold{'degdiff'} = $coursesettings{'internal.threshold_degdiff'};
    }
    if (exists($coursesettings{'internal.threshold_numstudents'})) {
        $$threshold{'numstudents'} = $coursesettings{'internal.threshold_numstudents'};
    }
}

sub process_reset {
    my ($dom,$crs) = @_;
    my $result = '<b>Counters reset for following problems (and parts):</b><br />';
    my @agg_types = ('attempts','users','correct');
    my %agg_titles = (
                     attempts => 'Number of submissions',
                     users => 'Students with submissions',
                     correct => 'Number of correct submissions',
                     );
    my @resets = ();
    my %titles = ();
    foreach my $key (keys(%env)) {
        next if ($key !~ /^form\.reset_(.+)$/);
        my $title = &Apache::lonnet::unescape($env{'form.title_'.$1});
        my $reset_item = &Apache::lonnet::unescape($1);
        my %curr_aggregates = &Apache::lonnet::dump('nohist_resourcetracker',$dom,$crs,$reset_item);
        my %aggregates = ();
        my ($symb,$part) = split(/\0/,$reset_item);
        foreach my $type (@agg_types) {
            $aggregates{$reset_item."\0".$type} = 0;
        }  
	$aggregates{$reset_item."\0".'resettime'} = time;
        my $putresult = &Apache::lonnet::put('nohist_resourcetracker',\%aggregates,
                          $dom,$crs);
        if ($putresult eq 'ok') {
            $result .= $title.' -part '.$part.': ';
            my %new_aggregates = &Apache::lonnet::dump('nohist_resourcetracker',$dom,$crs,$reset_item);
            foreach my $type (@agg_types) {
                $result .= $agg_titles{$type}.' = '.$new_aggregates{$reset_item."\0".$type}.'; ';
            }
            $result =~ s/; $//;
            $result .= '<br />';
        } else {
            $result = $title.' -part '.$part.': '.&mt('Unable to reset counters to zero due to [_1]',$putresult).'.<br />'."\n";
        }
    }
    return $result;
}

sub process_update {
    my ($dom,$crs,$threshold_titles) = @_;
    my $setoutput = '<b>Changes to threshold(s) for problem tracking:</b><br />';
    foreach (keys %env) {
        next if ($_!~/^form\.(.+)\_setparmval$/);
        my $name  = $1;
        my $value = $env{'form.'.$name.'_value'};
        if ($name && defined($value)) {
            my $put_result = &Apache::lonnet::put('environment',
                                                  {$name=>$value},$dom,$crs);
           
            my ($shortname) = ($name =~ /^internal\.threshold_(.+)$/); 
            if ($put_result eq 'ok') {
                $setoutput.=&mt('Set threshold for [_1] to [_2]',
				'<b>'.$$threshold_titles{$shortname}.'</b>',
				'<b>'.$value.'</b>').'<br />';
	    } else {
                $setoutput.=&mt('Unable to set threshold for [_1] to [_2] due to [_3].',
				'<b>'.$name.'</b>','<b>'.$value.'</b>',
				'<tt>'.$put_result.'</tt>').'<br />';
            }
        }
    }
    return $setoutput;
}

sub getnormalmail {
    my ($newmsgs) = @_;
# Check for unread mail in course
    my $msgcount = 0;

    my @messages = sort(&Apache::lonnet::getkeys('nohist_email'));
    foreach my $message (@messages) {
	my $msgid=&Apache::lonnet::escape($message);
        my ($sendtime,$shortsubj,$fromname,$fromdom,$status,$fromcid)=
            &Apache::lonmsg::unpackmsgid($msgid);
        if (($fromcid) && ($fromcid eq $env{'request.course.id'})) {
            if (defined($sendtime) && $sendtime!~/error/) {
                my $numsendtime = $sendtime;
                $sendtime = &Apache::lonlocal::locallocaltime($sendtime);
                if ($status eq 'new') {
                    $msgcount ++;
                    if ($shortsubj eq '') {
                        $shortsubj = &mt('No subject');
                    }
                    $shortsubj = &Apache::lonnet::unescape($shortsubj);
                    push(@{$newmsgs}, {
                        msgid    => $msgid,
                        sendtime => $sendtime,
                        shortsub => $shortsubj,
                        from     => $fromname,
                        fromdom  => $fromdom
                        });
                }
            }
        }
    }
    return $msgcount;
}

sub getcritmail {
    my ($critmsgs) = @_; 
# Check for critical messages in course
    my %what=&Apache::lonnet::dump('critical');
    my $result = '';
    my $critmsgcount = 0;
    foreach my $msgid (sort(keys(%what))) {
        my ($sendtime,$shortsubj,$fromname,$fromdom,$status,$fromcid)=
            &Apache::lonmsg::unpackmsgid($msgid);
        if (($fromcid) && ($fromcid eq  $env{'request.course.id'})) {
            if (defined($sendtime) && $sendtime!~/error/) {
                my $numsendtime = $sendtime;
                $sendtime = &Apache::lonlocal::locallocaltime($sendtime);
                $critmsgcount ++;
                if ($shortsubj eq '') {
                    $shortsubj = &mt('No subject');
                }
                $shortsubj = &Apache::lonnet::unescape($shortsubj);
                push(@{$critmsgs}, {
                        msgid    => $msgid,
                        sendtime => $sendtime,
                        shortsub => $shortsubj,
                        from     => $fromname,
                        fromdom  => $fromdom
                        });
            }
        }
    }
    return $critmsgcount;
}


sub checkversions {
    my ($cdom,$crs,$navmap,$changed,$starttime) = @_;
    my %changes=&Apache::lonnet::dump('versionupdate',$cdom,$crs);
    my ($tmp) = keys(%changes);
    if ($tmp =~/^error\:/) {
        &Apache::lonnet::logthis('Error retrieving version update information: '.
        $tmp.' for '.$cdom.'_'.$crs.' in whatsnew');
    } else {
        if (keys(%changes) > 0) {
            foreach my $key (sort(keys(%changes))) {
                if ($changes{$key} > $starttime) {
                    my $version;
                    my ($root,$extension)=($key=~/^(.*)\.(\w+)$/);
                    my $currentversion=&Apache::lonnet::getversion($key);
                    my $revdate = 
                          &Apache::lonnet::metadata($root.'.'.$extension,
                                                     'lastrevisiondate');
                    $revdate =  &Apache::lonlocal::locallocaltime($revdate);
                    my $linkurl=&Apache::lonnet::clutter($key);
                    my $usedversion=$navmap->usedVersion('version_'.$linkurl);
                    my @resources = $navmap->getResourceByUrl($linkurl,1);
                    if (($usedversion) && ($usedversion ne 'mostrecent')) {
                        $version = $usedversion;     
                    } else {
                        $version = $currentversion;
                    }
                    foreach my $res (@resources) {
                         if (ref($res) eq 'Apache::lonnavmaps::resource') { 
                            my $symb = $res->symb();
                            %{$$changed{$symb}} = (
                                                current => $currentversion,
                                                version => $version,
                                                revdate => $revdate,
                            );
                        }
                    }
                }
            }
        }
    }
    return;
}

sub display_handgrade {
    my ($r,$tograde,$rowColor1,$rowColor2,$ungraded) = @_;
    my $rowColor;
    my %lt = &Apache::lonlocal::texthash(
                        'prna' => 'Problem Name',
                        'nmun' => 'Number ungraded',
                        'nopr' => 'No problems require handgrading',
    );
    if (@{$tograde} > 0) {
        $r->print('<tr bgcolor="#cccccc"><td><b><small>'.$lt{'prna'}.'</small></b></td><td align="right"><b><small>'.$lt{'nmun'}.'</small></b></td></tr>');
        my $rowNum = 0;
        foreach my $res (@{$tograde}) {
            if ($rowNum %2 == 1) {
                $rowColor = $rowColor1;
            } else {
                $rowColor = $rowColor2;
            }
            my ($map,$id,$url)=&Apache::lonnet::decode_symb($res);
            my $linkurl=&Apache::lonnet::clutter($url);
            $linkurl .= '?symb='.&Apache::lonnet::escape($res);
                                                                               
            $r->print('<tr bgcolor="'.$rowColor.'"><td><a href="'.$linkurl.'"><small>'.$$ungraded{$res}{title}.'</small></a></td><td align="right"><small>'.$$ungraded{$res}{count}.'</small></td></tr>');
            $rowNum ++;
        }
    } else {
        $r->print('<tr><td bgcolor="#ffffff"><br><center><i><b><small>&nbsp;&nbsp;'.$lt{'nopr'}.'&nbsp;&nbsp;</small><br><br></b></i></td></tr>');
    }
}

sub display_haserrors {
    my ($r,$bombs,$rowColor1,$rowColor2,$bombed,$res_title) = @_;
    my $bombnum = 0;
    my $rowColor;
    my %lt = &Apache::lonlocal::texthash(
                                   reso => 'Resource',
                                   nmer => 'Number of errors',
                                   noer => 'No problems with errors',
    );
    if (@{$bombs} > 0) {
        $r->print('<tr bgcolor="#cccccc"><td><b><small>'.$lt{'reso'}.'</small></b></td><td align="right"><b><small>'.$lt{'nmer'}.'</small></b></td></tr>');
        @{$bombs} = sort { &cmp_title($a,$b,$res_title) } @{$bombs};
        foreach my $bomb (@{$bombs}) {
            if ($bombnum %2 == 1) {
                $rowColor = $rowColor1;
            } else {
                $rowColor = $rowColor2;
            }
            $r->print('<tr bgcolor="'.$rowColor.'"><td><small>'.$$bombed{$bomb}{errorlink}.'</small></td><td align="right"><small>'.$$bombed{$bomb}{errorcount}.'</small></td></tr>');
            $bombnum ++;
        }
    } else {
        $r->print('<tr><td bgcolor="#ffffff"><br /><center><b><i><small>'.$lt{'noer'}.'</small></i></b></center><br /></td></tr>');
    }
    return;
}

sub display_abovethreshold {
    my ($r,$warnings,$triggered,$res_title,$rowColor1,$rowColor2) = @_;
    my %lt = &Apache::lonlocal::texthash(
                 reso => 'Resource',
                 part => 'Part',
                 nust => 'Num. students',
                 avat => 'Av. Attempts',
                 dedi => 'Deg. Diff',
                 lare => 'Last Reset',
                 reco => 'Reset Count?',
                 rese => 'Reset counters to 0',
                 nopr => 'No problems satisfy threshold criteria',
    );
    my $rowColor; 
    my $warningnum = 0;
    if (@{$warnings} > 0) {
        @{$warnings} = sort { &cmp_title($a,$b,$res_title) } @{$warnings};
        $r->print('<form name="reset_tracking" method="post">'.
                '  <input type="hidden" name="action" value="reset" />'."\n");
        $r->print('<tr bgcolor="#cccccc"><td><b><small>'.$lt{'reso'}.'</small></b></td><td align="right"><b><small>'.$lt{'part'}.'</small></b></td><td align="right"><b><small>'.$lt{'nust'}.'</small></b></td><td align="right"><b><small>'.$lt{'avat'}.'</small></b></td><td align="right"><b><small>'.$lt{'dedi'}.'</small></b></td><td align="right"><b><small>'.$lt{'lare'}.'</small></b></td><td align="right"><b><small>'.$lt{'reco'}.'</small></b></td></tr>');
        foreach my $res (@{$warnings}) {
            if ($warningnum %2 == 1) {
                $rowColor = $rowColor1;
            } else {
                $rowColor = $rowColor2;
            }
            my ($map,$id,$url)=&Apache::lonnet::decode_symb($res);
            my $linkurl=&Apache::lonnet::clutter($url);
            my $rowspan;
            if ($$triggered{$res}{numparts} > 1) {
                $rowspan = 'rowspan="'.$$triggered{$res}{numparts}.'"';
            }
            $linkurl .= '?symb='.&Apache::lonnet::escape($res);
            $r->print('<tr bgcolor="'.$rowColor.'"><td '.$rowspan.'><a href="'.$linkurl.'"><small>'.$$triggered{$res}{title}.'</small></a></td>'.$$triggered{$res}{text});
            $warningnum ++;
        }
        $r->print('<tr bgcolor="#cccccc"><td colspan="7" align="right"><br /><b><small><input type="submit" name="counters" value="'.$lt{'rese'}.'" /></form>');
    } else {
        $r->print('<tr><td bgcolor="#ffffff"><br /><center><b><i><small>'.$lt{'nopr'}.'</small></i></b></center><br /></td></tr>');
    }
}

sub display_versionchanges {
    my ($r,$changed,$res_title,$rowColor1,$rowColor2,$interval) = @_;
    my %lt = &Apache::lonlocal::texthash(
        'reso' => 'Resource',
        'revd' => 'Last revised',
        'newv' => 'New version',
        'veru' => 'Version used',
        'noup' => 'No updated versions', 
    );
    my $rowColor;
    if (keys(%{$changed}) > 0) {
        $r->print('<tr bgcolor="#cccccc"><td><b><small>'.$lt{'reso'}.'</small></b></td><td><b><small>'.$lt{'revd'}.'</small></b></td><td><b><small>'.$lt{'newv'}.'</small></b></td><td><b><small>'.$lt{'veru'}.'</small></b></td></tr>');
        
        
        my @changes = sort { &cmp_title($a,$b,$res_title) } keys(%{$changed});
        my $changenum = 0;
        foreach my $item (@changes) {
            if ($changenum %2 == 1) {
                $rowColor = $rowColor1;
            } else {
                $rowColor = $rowColor2;
            }
            my ($map,$id,$url)=&Apache::lonnet::decode_symb($item);
            my $linkurl=&Apache::lonnet::clutter($url);
            $linkurl .= '?symb='.&Apache::lonnet::escape($item);

            $r->print('<tr bgcolor="'.$rowColor.'"><td><small><a href="'.$linkurl.'">'.$$res_title{$item}.'</a></small></td><td><small>'.$$changed{$item}{'revdate'}.'</small></td><td><small>'.$$changed{$item}{'current'}.'</small></td><td><small>'.$$changed{$item}{'version'}.'</small></td></tr>');
            $changenum ++;
        }
    } else {
        $r->print('<tr><td bgcolor="#ffffff"><br /><center><b><i><small>'.$lt{'noup'}.' '.$interval.'</small></i></b></center><br /></td></tr>');
    }
    return;
}
 
sub display_coursediscussion {
    my ($r,$newdiscussions,$unread,$res_title,$rowColor1,$rowColor2) = @_;
    my %lt = &Apache::lonlocal::texthash(
                'loca' => 'Location',
                'type' => 'Type',
                'numn' => 'Number of new posts',
                'noun' => 'No unread posts in course discussions',
    );
    my $rowColor;
    if (@{$newdiscussions} > 0) {
        $r->print('<tr bgcolor="#cccccc"><td><b><small>'.$lt{'loca'}.
                  '</small></b></td><td><b><small>'.$lt{'type'}.
                  '</small></b><td align="right"><b><small>'.$lt{'numn'}.
                  '</small></b></td></tr>');
        @{$newdiscussions} = sort { &cmp_title($a,$b,$res_title) }
                                                            @{$newdiscussions};
        my $rowNum = 0;
        foreach my $ressymb (@{$newdiscussions}) {
            my $forum_title = $$unread{$ressymb}{'title'};
            my $type = 'Resource';
            my $feedurl=&Apache::lonfeedback::get_feedurl($ressymb);
            if ($feedurl =~ /bulletinboard/) {
                $type = 'Bulletin Board';
            }
            my $unreadnum = keys(%{$$unread{$ressymb}});
            $unreadnum = $unreadnum - 2;
            if ($unreadnum > 0) {
                if ($rowNum %2 == 1) {
                    $rowColor = $rowColor1;
                } else {
                    $rowColor = $rowColor2;
                }
                $r->print('<tr bgcolor="'.$rowColor.'"><td><small><a href="'.$feedurl.'?symb='.$$unread{$ressymb}{symb}.'">'.$forum_title.'</a>&nbsp;</td><td><small>'.$type.'</small></td><td align="right">'.$unreadnum.'&nbsp;</td></tr>');
                $rowNum ++;
            }
        }
    } else {
        $r->print('<tr><td bgcolor="#ffffff"><br><center>&nbsp;<i><b><small>'.
                  $lt{'noun'}.'</small></b></i><br><br></td></tr>');
    }
}

sub display_coursenormalmail {
    my ($r,$msgcount,$newmsgs,$rowColor1,$rowColor2) = @_;
    my $rowColor;
    if ($msgcount > 0) {
        $r->print('<tr bgcolor="#cccccc"><td><b><small>'.&mt('Number').'</small></b></td><td><b><small>'.&mt('Subject').'</small></b></td><td><b><small>'.&mt('Sender').'</small></b></td><td><b><small>'.&mt('Date/Time').'</small></b></td></tr>');
        my $rowNum = 0;
        my $mailcount = 1;
        foreach my $msg (@{$newmsgs}) {
            if ($rowNum %2 == 1) {
                $rowColor = $rowColor1;
            } else {
                $rowColor = $rowColor2;
            }
            $r->print('<tr bgcolor="'.$rowColor.'"><td valign="top"><small>'.$mailcount.'. &nbsp;</small></td><td valign="top"><small><a href="/adm/communicate">'.$msg->{'shortsub'}.'</a>&nbsp; &nbsp;</small></td><td valign="top"><small>&nbsp;'.$msg->{'from'}.'@'.$msg->{'fromdom'}.'&nbsp;</small></td><td valign="top"><small>'.$msg->{'sendtime'}.'</small></td></tr>');
            $rowNum ++;
            $mailcount ++;
        }
    } else {
        $r->print('<tr><td bgcolor="#ffffff" width="100%"><center><br /><b><i><small>'.&mt('No new course messages').'</small></i></b><br /><br /></center></td></tr>');
    }
}

sub display_coursecritmail {
    my ($r,$critmsgcount,$critmsgs,$rowColor1,$rowColor2) = @_;
    my $rowColor;
    if ($critmsgcount > 0) {
        $r->print('<tr bgcolor="#cccccc"><td><b><small>'.&mt('Number').'</small></b></td><td><b><small>'.&mt('Subject').'</small></b></td><td><b><small>'.&mt('Sender').'</small></b></td><td><b><small>'.&mt('Date/Time').'</small></b></td></tr>');
        my $rowNum = 0;
        my $mailcount = 1;
        foreach my $msg (@{$critmsgs}) {
            if ($rowNum %2 == 1) {
                $rowColor = $rowColor1;
            } else {
                $rowColor = $rowColor2;
            }
            $r->print('<tr bgcolor="'.$rowColor.'"><td valign="top"><small>'.$mailcount.'. &nbsp;<small></td><td valign="top"><small><a href="/adm/email?folder=critical">'.$msg->{'shortsub'}.'</a>&nbsp; &nbsp;</small></td><td valign="top"><small>&nbsp;'.$msg->{'from'}.'@'.$msg->{'fromdom'}.'&nbsp;</small></td><td valign="top"><small>'.$msg->{'sendtime'}.'</small></td></tr>');
            $rowNum ++;
            $mailcount ++;
        }
    } else {
        $r->print('<tr><td bgcolor="#ffffff" width="100%"><center><br /><b><i><small>'.&mt('No unread critical messages in course').'</small></i></b><br /><br /></center></td></tr>');
    }
}

sub cmp_title {
    my ($a,$b,$res_title) = @_;
    my ($atitle,$btitle) = (lc($$res_title{$a}),lc($$res_title{$b}));
    $atitle=~s/^\s*//;
    $btitle=~s/^\s*//;
    return $atitle cmp $btitle;
}

sub get_display_settings {
    my $udom = $env{'user.domain'};
    my $uname = $env{'user.name'};
    my $cid = $env{'request.course.id'};
    my %settings = &Apache::lonnet::dump('nohist_whatsnew',$udom,$uname,$cid); 
    my ($tmp) = keys(%settings);
    if ($tmp=~/^error:/) {
        %settings = ();
        unless ($tmp eq 'error: 2 tie(GDBM) Failed while attempting dump') {
            &logthis('Error retrieving whatsnew settings: '.$tmp.' for '.
                                $uname.':'.$udom.' for course: '.$cid);
        }
    }
    return %settings;
}

sub start_box {
    my ($r,$tabbg,$show,$heading,$caller) = @_;
    my %lt = &Apache::lonlocal::texthash( 
                       chth => 'Change thresholds?',
                       chin => 'Change interval?',
    );
    my $showhide;
    if ($$show{$caller}) {
        $showhide = '<b><a href="javascript:change_display('."'".$caller.
                                           "','hide'".');">Hide</a></b>';
   
    } else {
        $showhide = '<b><a href="javascript:change_display('."'".$caller.
                                            "','show'".');">Show</a></b>';
    }
    
    $r->print('
         <table border="0" cellpadding="0" cellspacing="0" bgcolor="#000000" width="100%">
          <tr>
           <td>
            <table border="0" cellpadding="1" cellspacing="1" bgcolor="#000000" width="100%">
              <tr>
               <td bgcolor="'.$tabbg.'">
                <table width="100%" border="0" cellspacing="0" cellpadding="0">
                 <tr>
                  <td><b>'.$$heading{$caller}.'</b></td>
                  <td valign="top" align="right">'.$showhide.'</td>
                 </tr>
                </table>
               </td>
              </tr>');
     if (($caller eq 'abovethreshold') && ($$show{$caller})) {
         $r->print('
              <tr>
                <td bgcolor="'.$tabbg.'" align="right"><a href="/adm/whatsnew?command=chgthreshold"><b><small>'.$lt{'chth'}.'</small></b></a></td>
              </tr>');
     } elsif (($caller eq 'versionchanges') && ($$show{$caller})) {
         $r->print('
              <tr>
                <td bgcolor="'.$tabbg.'" align="right"><a href="/adm/whatsnew?command=chginterval"><b><small>'.$lt{'chin'}.'</small></b></a></td>
              </tr>');
     }
     $r->print('
              <tr>
               <td bgcolor="#ffffff">
                <table cellpadding="2" cellspacing="0" border="0" width="100%">
');
    return;
}

sub end_box {
    my ($r) = shift;
    $r->print('
      </table>
     </td>
    </tr>
   </table>
  </td>
 </tr>
</table><br />');
    return;
}

1;