# The LearningOnline Network
# Feedback
#
# $Id: lonfeedback.pm,v 1.370.2.5.2.1 2021/12/31 20:39:00 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::lonfeedback;

use strict;
use Apache::Constants qw(:common);
use Apache::lonmsg();
use Apache::loncommon();
use Apache::lontexconvert();
use Apache::lonlocal; # must not have ()
use Apache::lonnet;
use Apache::lonhtmlcommon();
use Apache::lonnavmaps;
use Apache::lonenc();
use Apache::lonrss();
use HTML::LCParser();
#use HTML::Tidy::libXML;
use Apache::lonspeller();
use Apache::longroup;
use Archive::Zip qw( :ERROR_CODES );
use LONCAPA qw(:DEFAULT :match);

sub discussion_open {
    my ($status,$symb)=@_;
# Advanced roles can always discuss
    if ($env{'request.role.adv'}) { return 1; }
# Get discussion closing date
    my $close=&Apache::lonnet::EXT('resource.0.discussend',$symb);
# If it is defined and in the future, the instructor wants this discussion to be open
    if (defined($close) && $close ne '' && $close > time) {
        return 1;
    }
# It was not explicitly open, check if the problem is available.
# If the problem is not available, close the discussion 
    if (defined($status) &&
	!($status eq 'CAN_ANSWER' || $status eq 'CANNOT_ANSWER'
	  || $status eq 'OPEN')) {
	return 0;
    }
# The problem is available, but check if the instructor explictly closed discussion
    if (defined($close) && $close ne '' && $close < time) {
	return 0;
    }
    return 1;
}

sub discussion_visible {
    my ($status)=@_;
    if (not &discussion_open($status)) {
	my $hidden=&Apache::lonnet::EXT('resource.0.discusshide');
	if (lc($hidden) eq 'yes' or $hidden eq '' or !defined($hidden))  {
	    if (!$env{'request.role.adv'}) { return 0; }
	}
    }
    return 1;
}

sub discussion_vote_available {
    my ($status,$symb)=@_;
    my $canvote=&Apache::lonnet::EXT('resource.0.discussvote',$symb);
    if ((lc($canvote) eq 'yes') || 
        ((lc($canvote) eq 'notended') && (&discussion_open($status,$symb)))) {
        return 1;
    }
}

sub get_realsymb {
    my ($symb) = @_;
    my $realsymb = $symb;
    if ($symb=~/^bulletin___/) {
        my $filename=(&Apache::lonnet::decode_symb($symb))[2];
        $filename=~s{^adm/wrapper/}{};
        $realsymb=&Apache::lonnet::symbread($filename);
    }
    return $realsymb;
}

sub list_discussion {
    my ($mode,$status,$ressymb,$imsextras,$group)=@_;
    unless ($ressymb) { $ressymb=&Apache::lonnet::symbread(); }
    unless ($ressymb) { return ''; }
    $ressymb=&wrap_symb($ressymb);
    my $outputtarget=$env{'form.grade_target'};
    if (defined($env{'form.export'})) {
	if($env{'form.export'}) {
            $outputtarget = 'export';
        }
    }
    if (defined($imsextras)) {
        if ($$imsextras{'caller'} eq 'imsexport') {
            $outputtarget = 'export';
        }
    }
    my ($nofooter,$nodisclink,$nofdbklink);
    if (not &discussion_visible($status)) {
        if ($mode ne 'board') {
            ($nofooter,$nodisclink,$nofdbklink) = &check_menucoll();
            if ($nofooter || $nofdbklink) {
                return '<br />';
            } else {
                &Apache::lonenc::check_encrypt(\$ressymb);
                return '<br /><div class="LC_feedback_link">'.&send_message_link($ressymb)."</div>";
            }
        }
    }
    if ($group ne '' && $mode eq 'board') {
        if (&check_group_priv($group,'vgb') ne 'ok') {
            return '';
        }
    }

    unless ($outputtarget eq 'export') {
        ($nofooter,$nodisclink,$nofdbklink) = &check_menucoll();
    }

    unless ($nofooter) {
        my ($blocked,$blocktext) = 
            &Apache::loncommon::blocking_status('boards');
        if ($blocked) {
            my $footer = '<br /><div class="LC_feedback_link">';
            unless ($nodisclink) {
                $footer .= '<span class="LC_feedback_link">'.$blocktext.'</span>';
            }
            &Apache::lonenc::check_encrypt(\$ressymb);
            if ($mode ne 'board') {
                unless ($nofdbklink) {
                    $footer.=&send_message_link($ressymb);
                }
            }
            $footer.='</div>';
            return $footer;
        }
    }

    my @bgcols = ("LC_disc_old_item","LC_disc_new_item");
    my $discussiononly=0;
    if ($mode eq 'board') { $discussiononly=1; }
    unless ($env{'request.course.id'}) { return ''; }
    my $crs='/'.$env{'request.course.id'};
    my $cid=$env{'request.course.id'};
    if ($env{'request.course.sec'}) {
	$crs.='_'.$env{'request.course.sec'};
    }
    $crs=~s/\_/\//g;
    my $encsymb=&Apache::lonenc::check_encrypt($ressymb);
    my $viewgrades=(&Apache::lonnet::allowed('vgr',$crs)
		  && ($ressymb=~/$LONCAPA::assess_re/));
    
    my %usernamesort = ();
    my %namesort =();
    my %subjectsort = ();

# Get discussion display settings for this discussion
    my $lastkey = $ressymb.'_lastread';
    my $showkey = $ressymb.'_showonlyunread';
    my $markkey = $ressymb.'_showonlyunmark',
    my $visitkey = $ressymb.'_visit';
    my $ondispkey = $ressymb.'_markondisp';
    my $userpickkey = $ressymb.'_userpick';
    my $toggkey = $ressymb.'_readtoggle';
    my $readkey = $ressymb.'_read';
    $ressymb=$encsymb;
    my %dischash = &Apache::lonnet::get('nohist_'.$cid.'_discuss',[$lastkey,$showkey,$markkey,$visitkey,$ondispkey,$userpickkey,$toggkey,$readkey],$env{'user.domain'},$env{'user.name'});
    my %discinfo = ();
    my $showonlyunread = 0;
    my $showunmark = 0; 
    my $markondisp = 0;
    my $prevread = 0;
    my $previous = 0;
    my $visit = 0;
    my $newpostsflag = 0;
    my @posters = split(/\&/,$dischash{$userpickkey});

# Retain identification of "NEW" posts identified in last display, if continuing 'previous' browsing of posts.
    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['previous','sortposts','rolefilter','statusfilter','sectionpick','grouppick','totposters']);
    my $sortposts = $env{'form.sortposts'};
    my $statusfilter = $env{'form.statusfilter'};
    my @sectionpick = split(/,/,$env{'form.sectionpick'});
    my @grouppick   = split(/,/,$env{'form.grouppick'});
    my @rolefilter  = split(/,/,$env{'form.rolefilter'});

    my $totposters = $env{'form.totposters'};
    $previous = $env{'form.previous'};
    if ($previous > 0) {
        $prevread = $previous;
    } elsif (defined($dischash{$lastkey})) {
        unless ($dischash{$lastkey} eq '') {
            $prevread = $dischash{$lastkey};
        }
    }

    my $cdom = $env{'course.'.$cid.'.domain'};
    my $cnum = $env{'course.'.$cid.'.num'};
    my $crstype = &Apache::loncommon::course_type();

# Get information about students and non-students in course for filtering display of posts
    my %roleshash = ();
    my %roleinfo = ();
    my ($classgroups,$studentgroups);
    if ($env{'form.rolefilter'}) {
        %roleshash = &Apache::lonnet::dump('nohist_userroles',$cdom,$cnum);
        foreach my $rolekey (keys(%roleshash)) {
            my ($role,$uname,$udom,$sec) = split(/:/,$rolekey);
            if ($role =~ /^cr/) {
                $role = 'cr';
            }
            my ($end,$start) = split(/:/,$roleshash{$rolekey});
            my $now = time;
            my $status = 'Active';
            if (($now < $start) || ($end > 0 && $now > $end)) {
                $status = 'Expired';
            }
            if ($uname && $udom) { 
                push(@{$roleinfo{$uname.':'.$udom}}, $role.':'.$sec.':'.$status);
            }
        }
        my ($classlist,$keylist) =
                         &Apache::loncoursedata::get_classlist($cdom,$cnum);
        my $sec_index = &Apache::loncoursedata::CL_SECTION();
        my $status_index = &Apache::loncoursedata::CL_STATUS();
        while (my ($student,$data) = each %$classlist) {
            my ($section,$status) = ($data->[$sec_index],
                                 $data->[$status_index]);
            push(@{$roleinfo{$student}}, 'st:'.$section.':'.$status);
        }
	($classgroups,$studentgroups) = 
	    &Apache::loncoursedata::get_group_memberships($classlist,$keylist,
							  $cdom,$cnum);
    }

# Get discussion display default settings for user
    if ($env{'environment.discdisplay'} eq 'unread') {
        $showonlyunread = 1;
    }
    if ($env{'environment.discmarkread'} eq 'ondisp') {
        $markondisp = 1;
    }

# Override user's default if user specified display setting for this discussion
    if (defined($dischash{$ondispkey})) {
        unless ($dischash{$ondispkey} eq '') {
            $markondisp = $dischash{$ondispkey};
        }
    }
    if ($markondisp) {
        $discinfo{$lastkey} = time;
    }

    if (defined($dischash{$showkey})) {
        unless ($dischash{$showkey} eq '') {
            $showonlyunread = $dischash{$showkey};
        }
    }

    if (defined($dischash{$markkey})) {
        unless ($dischash{$markkey} eq '') {
            $showunmark = $dischash{$markkey};
        }
    }

    if (defined($dischash{$visitkey})) {
        unless ($dischash{$visitkey} eq '') {
            $visit = $dischash{$visitkey};
        }
    }
    $visit ++;

    my $seeid;
    if (&Apache::lonnet::allowed('rin',$env{'request.course.id'}.($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:''))) {
        $seeid = 1;
    }
    my $seehidden = &can_see_hidden($mode,$ressymb,undef,$group,$cdom,$cnum,$crs);

# Is voting on discussions available
    my $realsymb = &get_realsymb($ressymb);
    my $canvote = &discussion_vote_available($status,$realsymb);

    my @discussionitems=();
    my %shown = ();
    my @posteridentity=();

    my $current=0;
    my $visible=0;
    my @depth=();
    my @replies = ();
    my %alldiscussion=();
    my %imsitems=();
    my %imsfiles=();
    my %notshown = ();
    my %newitem = ();
    my $maxdepth=0;
    my %anonhash=();
    my $anoncnt=0;

    my $now = time;
    $discinfo{$visitkey} = $visit;

    &Apache::lonnet::put('nohist_'.$cid.'_discuss',\%discinfo,$env{'user.domain'},$env{'user.name'});
    &build_posting_display(\%usernamesort,\%subjectsort,\%namesort,\%notshown,\%newitem,\%dischash,\%shown,\%alldiscussion,\%imsitems,\%imsfiles,\%roleinfo,\@discussionitems,\@replies,\@depth,\@posters,\$maxdepth,\$visible,\$newpostsflag,\$current,$status,$viewgrades,$seeid,$seehidden,$canvote,$prevread,$sortposts,$encsymb,$readkey,$showunmark,$showonlyunread,$totposters,\@rolefilter,\@sectionpick,\@grouppick,$classgroups,$statusfilter,$toggkey,$outputtarget,\%anonhash,$anoncnt,$group);

    my $discussion='';
    my $manifestfile;
    my $manifestok=0;
    my $tempexport;
    my $imsresources;
    my $copyresult;

    my $function = &Apache::loncommon::get_users_function();
    my %lt = &Apache::lonlocal::texthash(
        'cuse' => 'My settings for this discussion',
        'allposts' => 'All posts',
        'unread' => 'New posts only',
        'unmark' => 'Unread only',
        'ondisp' => 'Once displayed',
        'onmark' => 'Once marked not NEW',
        'toggoff' => 'Off',
        'toggon' => 'On',
        'disa' => 'Posts to be displayed',
        'npce' => 'Posts cease to be marked "NEW"',
        'epcb' => 'Each post can be toggled read/unread', 
        'chgt' => 'Change',
        'disp' => 'Display',
        'nolo' => 'Not new',
        'togg' => 'Toggle read/unread',
        'aner' => 'An error occurred opening the manifest file.',
        'difo' => 'Discussion for',
        'aerr' => 'An error occurred opening the export file for posting',
        'discussions' => 'DISCUSSIONS'
    );
    my %js_lt = &Apache::lonlocal::texthash(
        'aysu' => 'Are you sure you want to delete this post?',
        'dpwn' => 'Deleted posts will no longer be visible to you and other students',
        'bwco' => 'but will continue to be visible to your instructor',
        'depo' => 'Deleted posts will no longer be visible to you or anyone else.',
    );
    &js_escape(\%js_lt);

    my $currdisp = $lt{'allposts'};
    my $currmark = $lt{'onmark'};
    my $currtogg = $lt{'toggoff'};
    my $dispchange = $lt{'unread'};
    my $markchange = $lt{'ondisp'};
    my $toggchange = $lt{'toggon'};
    my $chglink = '/adm/feedback?modifydisp='.$ressymb;
    my $displinkA = 'onlyunread';
    my $displinkB = 'onlyunmark';
    my $marklink = 'markondisp';
    my $togglink = 'toggon';

    if ($markondisp) {
        $currmark = $lt{'ondisp'};
        $markchange = $lt{'onmark'};
        $marklink = 'markonread';
    }

    if ($showonlyunread) {
        $currdisp = $lt{'unread'};
        $dispchange = $lt{'allposts'};
        $displinkA = 'allposts';
    }

    if ($showunmark) {
        $currdisp = $lt{'unmark'};
        $dispchange = $lt{'unmark'};
        $displinkA='allposts';
        $displinkB='onlyunread';
        $showonlyunread = 0;
    }

    if ($dischash{$toggkey}) {
        $currtogg = $lt{'toggon'};
        $toggchange = $lt{'toggoff'};
        $togglink = 'toggoff';
    } 
   
    $chglink .= '&amp;changes='.$displinkA.'_'.$displinkB.'_'.$marklink.'_'.$togglink;

    if ($newpostsflag) {
        $chglink .= '&amp;previous='.$prevread;
    }
    $chglink.=&group_args($group);

    if ($visible) {
# Print the discusssion
        if ($outputtarget eq 'tex') {
            $discussion.='<tex>{\tiny \vskip 0 mm\noindent\makebox[2 cm][b]{\hrulefill}'.
                         '\textbf{'.$lt{'discussions'}.'}\makebox[2 cm][b]{\hrulefill}\vskip 0 mm'.
                         '\noindent\textbf{'.$lt{'disa'}.'}: \textit{'.$currdisp.'}\vskip 0 mm'.
                         '\noindent\textbf{'.$lt{'npce'}.'}: \textit{'.$currmark.'}}</tex>';
        } elsif ($outputtarget eq 'export') {
# Create temporary directory if this is an export
            my $now = time;
            if ((defined($imsextras)) && ($$imsextras{'caller'} eq 'imsexport')) {
                $tempexport = $$imsextras{'tempexport'};
                if (!-e $tempexport) {
                    mkdir($tempexport,0700);
                }
                $tempexport .= '/'.$$imsextras{'count'};
                if (!-e $tempexport) {
                    mkdir($tempexport,0700);
                }
            } else {
                $tempexport = $Apache::lonnet::perlvar{'lonDaemons'}.'/tmp/ims_exports';
                if (!-e $tempexport) {
                    mkdir($tempexport,0700);
                }
                $tempexport .= '/'.$now;
                if (!-e $tempexport) {
                    mkdir($tempexport,0700);
                }
                $tempexport .= '/'.$env{'user.domain'}.'_'.$env{'user.name'};
            }
            if (!-e $tempexport) {
                mkdir($tempexport,0700);
            }
# open manifest file
            my $manifest = '/imsmanifest.xml';
            my $manifestfilename = $tempexport.$manifest;
            if ($manifestfile = Apache::File->new('>'.$manifestfilename)) {
                $manifestok=1;
                print $manifestfile qq|<?xml version="1.0" encoding="UTF-8"?>
<manifest xmlns="http://www.imsglobal.org/xsd/imscp_v1p1" xmlns:imsmd="http://www.imsglobal.org/xsd/imsmd_v1p2" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
identifier="MANIFEST-$ressymb" xsi:schemaLocation="http://www.imsglobal.org/xsd/imscp_v1p1 
imscp_v1p1.xsd http://www.imsglobal.org/xsd/imsmd_v1p2 imsmd_v1p2p2.xsd">
  <organizations default="$ressymb">
    <organization identifier="$ressymb">
      <title>$lt{'difo'} $ressymb</title>\n|;
            } else {
                $discussion .= $lt{'aner'}.'<br />';
            }
	} else {
            my $colspan=$maxdepth+1;
            $discussion.= &Apache::lonhtmlcommon::scripttag(qq|
   function verifydelete (caller,symb,idx,newflag,previous,groupparm) {
       var symbparm = symb+':::'+idx
       var prevparm = ""
       if (newflag == 1) {
           prevparm = "&amp;previous="+previous
       }
       if (caller == 'studentdelete') {
           if (confirm("$js_lt{'aysu'}\\n$js_lt{'dpwn'},\\n$js_lt{'bwco'}")) {
               document.location.href = "/adm/feedback?hide="+symbparm+prevparm+groupparm
           }
       } else {
           if (caller == 'seeiddelete') {
               if (confirm("$js_lt{'aysu'}\\n$js_lt{'depo'}")) {
                   document.location.href = "/adm/feedback?deldisc="+symbparm+prevparm+groupparm
               }
           }
       }
   }
            |);
	    $discussion.='<form name="readchoices" method="post" action="/adm/feedback?chgreads='.$ressymb.'" >'.
                         "\n".'<table width="100%" class="LC_discussion">';
            $discussion .= &action_links_bar($colspan,$ressymb,$visible,
                                             $newpostsflag,$group,
                                             $prevread,$markondisp,$seehidden);
            my $escsymb=&escape($ressymb);
            my $numhidden = keys(%notshown);
            if ($numhidden > 0) {
                my $colspan = $maxdepth+1;
                $discussion.="\n".'<tr><td bgcolor="#CCCCCC" colspan="'.$colspan.'">';
                my $href = '/adm/feedback?allposts=1&amp;symb='.$escsymb;
                if ($newpostsflag) {
                    $href .= '&amp;previous='.$prevread;
                }
		$href .= &group_args($group);
                if ($showunmark) {
                    $discussion .= &mt('[_1]Show all posts[_2] to display [quant,_3,post] previously marked read',
                                       '<a href="'.$href.'">','</a>',$numhidden);
                } else {
                    $discussion .= &mt('[_1]Show all posts[_2] to display [quant,_3,post] previously viewed',
                                       '<a href="'.$href.'">','</a>',$numhidden);
                }
                $discussion .= '<br/></td></tr>';
            }
        }

# Choose sort mechanism
        my @showposts = ();
        if ($sortposts eq 'descdate') {
            @showposts = (sort { $b <=> $a } keys(%alldiscussion));
        } elsif ($sortposts eq 'thread') {
            @showposts = (sort { $a <=> $b } keys(%alldiscussion));
        } elsif ($sortposts eq 'subject') {
            foreach my $key (sort(keys(%subjectsort))) {
                push(@showposts, @{$subjectsort{$key}});
            }
        } elsif ($sortposts eq 'username') {
            foreach my $domain (sort(keys(%usernamesort))) {
                foreach my $key (sort(keys(%{$usernamesort{$domain}}))) {
                    push(@showposts, @{$usernamesort{$domain}{$key}});
                }
            }
        } elsif ($sortposts eq 'lastfirst') {
            foreach my $last (sort(keys(%namesort))) {
                 foreach my $key (sort(keys(%{$namesort{$last}}))) {
                     push(@showposts, @{$namesort{$last}{$key}});
                 }
            }
        } else {
            @showposts =  (sort { $a <=> $b } keys(%alldiscussion));
        }
        my $currdepth = 0;
        my $firstidx = $alldiscussion{$showposts[0]};
        foreach my $post (@showposts) {
            unless (($sortposts eq 'thread') || 
                    (($sortposts eq '') && (!$env{'environment.unthreadeddiscussion'})) || 
                    ($outputtarget eq 'export')) {
                $alldiscussion{$post} = $post;
            }
            unless ( ($notshown{$alldiscussion{$post}} eq '1') || ($shown{$alldiscussion{$post}} == 0) ) {
                if ($outputtarget ne 'tex' && $outputtarget ne 'export') {
		    $discussion.="\n<tr>";
		}
	        my $thisdepth=$depth[$alldiscussion{$post}];
                if ($outputtarget ne 'tex' && $outputtarget ne 'export') {
		    for (1..$thisdepth) {
			$discussion.='<td>&nbsp;&nbsp;&nbsp;&nbsp;</td>';
		    }
		}
	        my $colspan=$maxdepth-$thisdepth+1;
                if ($outputtarget eq 'tex') {
		    #cleanup block
		    $discussionitems[$alldiscussion{$post}]=~s/<table([^>]*)>/<table TeXwidth="90 mm">/;
		    $discussionitems[$alldiscussion{$post}]=~s/<tr([^>]*)><td([^>]*)>/<tr><td TeXwidth="20 mm" align="left">/;
                    my $threadinsert='';
                    if ($thisdepth > 0) {
			$threadinsert='<br /><strong>Reply: '.$thisdepth.'</strong>';
		    }
		    $discussionitems[$alldiscussion{$post}]=~s/<\/td><td([^>]*)>/$threadinsert<\/td><td TeXwidth="65 mm" align="left">/;
                    $discussionitems[$alldiscussion{$post}]=~s/(<b>|<\/b>|<\/a>|<a([^>]+)>)//g;

		    $discussionitems[$alldiscussion{$post}]='<tex>\vskip 0 mm\noindent\makebox[2 cm][b]{\hrulefill}</tex>'.$discussionitems[$alldiscussion{$post}];
		    $discussion.=$discussionitems[$alldiscussion{$post}];
		} elsif ($outputtarget eq 'export') {
                    my $postfilename = $alldiscussion{$post}.'-'.$imsitems{$alldiscussion{$post}}{'timestamp'}.'.html';
                    if ($manifestok) {
                        if (($depth[$alldiscussion{$post}] <= $currdepth) && ($alldiscussion{$post} != $firstidx)) {
                            print $manifestfile '  </item>'."\n";
                        }
                        $currdepth = $depth[$alldiscussion{$post}];
                        print $manifestfile "\n". 
      '<item identifier="ITEM-'.$ressymb.'-'.$alldiscussion{$post}.'" isvisible="'.
        $imsitems{$alldiscussion{$post}}{'isvisible'}.'" identifieref="RES-'.$ressymb.'-'.$alldiscussion{$post}.'">'.
        '<title>'.$imsitems{$alldiscussion{$post}}{'title'}.'</title></item>';
                        $imsresources .= "\n".
    '<resource identifier="RES-'.$ressymb.'-'.$alldiscussion{$post}.'" type="webcontent" href="'.$postfilename.'">'."\n".
      '<file href="'.$postfilename.'">'."\n".
      $imsfiles{$alldiscussion{$post}}{$imsitems{$alldiscussion{$post}}{'currversion'}}.'</file>'."\n".
    '</resource>';
                    }
                    my $postingfile;
                    my $postingfilename = $tempexport.'/'.$postfilename;
                    if ($postingfile = Apache::File->new('>'.$postingfilename)) {
                        print $postingfile '<html><head><title>'.&mt('Discussion Post').'</title></head><body>'.
                                           $imsitems{$alldiscussion{$post}}{'title'}.' '.
                                           $imsitems{$alldiscussion{$post}}{'sender'}.
                                           $imsitems{$alldiscussion{$post}}{'timestamp'}.'<br /><br />'.
                                           $imsitems{$alldiscussion{$post}}{'message'}.'<br />'.
                                           $imsitems{$alldiscussion{$post}}{'attach'}.'</body></html>'."\n"; 
                        close($postingfile);
                    } else {
                        $discussion .= $lt{'aerr'}.' '.$alldiscussion{$post}.'<br />';
                    }
                    $copyresult.=&replicate_attachments($imsitems{$alldiscussion{$post}}{'allattachments'},$tempexport);
                } else {
                    $discussion.='<td class="'.$bgcols[$newitem{$alldiscussion{$post}}].
                       '" colspan="'.$colspan.'">'. $discussionitems[$alldiscussion{$post}].
                       '</td></tr>';
                }
	    }
        }
	unless ($outputtarget eq 'tex' || $outputtarget eq 'export') {
            my $colspan=$maxdepth+1;
            $discussion .= <<END;
            <tr>
             <td colspan="$colspan">
              <table width="100%">
               <tr>
                <td class="LC_disc_action_left">
                    <font size="-1"><b>$lt{'cuse'}</b>:&nbsp;
END
            if ($newpostsflag) {
                $discussion .= 
                   '1.&nbsp;'.$lt{'disp'}.'&nbsp;-&nbsp;<i>'.$currdisp.'</i>&nbsp;&nbsp;2.&nbsp;'.$lt{'nolo'}.'&nbsp;-&nbsp;<i>'.$currmark.'</i>';
                if ($dischash{$toggkey}) {
                   $discussion .= '&nbsp;&nbsp;3.&nbsp;'.$lt{'togg'}.'&nbsp;-&nbsp;<i>'.$currtogg.'</i>';
                }
            } else {
                if ($dischash{$toggkey}) {
                   $discussion .= '1.&nbsp;'.$lt{'disp'}.'&nbsp;-&nbsp;<i>'.$currdisp.'</i>&nbsp;2.&nbsp;'.$lt{'togg'}.'&nbsp;-&nbsp;<i>'.$currtogg.'</i>';
                } else {
                    $discussion .=
                         $lt{'disp'}.'&nbsp;-&nbsp;<i>'.$currdisp.'</i>';
                }
            }
            $discussion .= <<END;
                   &nbsp;&nbsp;<b><a href="$chglink">$lt{'chgt'}</a></b></font>
                </td>
END
            if ($sortposts) {
                my %sort_types = ();
                my %role_types = ();
                my %status_types = ();
                &sort_filter_names(\%sort_types,\%role_types,\%status_types,$crstype);

                $discussion .= '<td class="LC_disc_action_right"><font size="-1"><b>'.&mt('Sorted by').'</b>: '.$sort_types{$sortposts}.'<br />';
                if (defined($env{'form.totposters'})) {
                    $discussion .= &mt('Posts by').':';
                    if ($totposters > 0) {
                        foreach my $poster (@posters) {
                            $discussion .= ' '.$poster.',';
                        }
                        $discussion =~ s/,$//;
                    } else {
                        $discussion .= &mt('None selected');
                    }
                } else {
                    my $filterchoice ='';
                    if (@sectionpick > 0) {
                        $filterchoice = '<i>'.&mt('sections').'</i>-&nbsp;'.$env{'form.sectionpick'};
                        $filterchoice .= '&nbsp;&nbsp;&nbsp; ';
                    }
                    if (@grouppick > 0) {
                        $filterchoice = '<i>'.&mt('groups').'</i>-&nbsp;'.$env{'form.grouppick'};
                        $filterchoice .= '&nbsp;&nbsp;&nbsp; ';
                    }
                    if (@rolefilter > 0) {
                        $filterchoice .= '<i>'.&mt('roles').'</i>-';
                        foreach my $role (@rolefilter) {
                            $filterchoice .= '&nbsp;'.$role_types{$role}.',';
                        }
                        $filterchoice =~ s/,$//;
                        $filterchoice .= '<br />'.('&nbsp;' x8);
                    }
                    if ($statusfilter) {
                        $filterchoice .= '<i>'.&mt('status').'</i>-&nbsp;'.$status_types{$statusfilter};
                    }
                    if ($filterchoice) {
                        $discussion .= '<b>'.&mt('Filters').'</b>:&nbsp;'.$filterchoice;
                    }
                }
                $discussion .= '</font></td>';

            }
            if ($dischash{$toggkey}) {
                my $storebutton = &mt('Save read/unread changes');
                $discussion.='<td align="right">'.
              '<input type="hidden" name="discsymb" value="'.$ressymb.'" />'."\n".
              '<input type="button" name="readoptions" value="'.$storebutton.'"'.
              ' onclick="this.form.submit();" />'."\n".
              '</td>';
            }
            $discussion .= (<<END);
               </tr>
              </table>
             </td>
            </tr>
END
            $discussion .= &action_links_bar($colspan,$ressymb,$visible,
                                             $newpostsflag,$group,
                                             $prevread,$markondisp,$seehidden);
            $discussion .= "</table></form>\n";
        }
        if ($outputtarget eq 'export') {
            if ($manifestok) {
                while ($currdepth > 0) {
                    print $manifestfile "    </item>\n";
                    $currdepth --;
                }
                print $manifestfile qq|
    </organization>
  </organizations>
  <resources>
    $imsresources
  </resources>
</manifest>
                |;
                close($manifestfile);
                if ((defined($imsextras)) && ($$imsextras{'caller'} eq 'imsexport')) {
                    $discussion = $copyresult;
                } else {

#Create zip file in prtspool

                    if (($env{'user.name'} =~ /^$match_username$/)
                        && ($env{'user.domain'} =~ /^$match_domain$/)) {
                        my $now = time();
                        my $imszipfile = '/prtspool/'.
                                      join('_',$env{'user.name'},$env{'user.domain'},$now).
                                      '_'.rand(1000000000).'.zip';
                        my $zip = Archive::Zip->new();
                        $zip->addTree($tempexport);
                        my $imszip = '/home/httpd/'.$imszipfile;
                        if ($zip->writeToFileNamed($imszip) == AZ_OK) {
                            $discussion .= &mt('Download the zip file from [_1]Discussion Posting Archive[_2]',
                                           '<a href="'.$imszipfile.'">','</a>').'<br />';
                        } else {
                            $discussion .=  &mt('Failed to create zip file').'<br />';
                        }
                        if ($copyresult) {
                            $discussion .= '<span class="LC_error">'.
                                           &mt('The following errors occurred during export:').
                                           '</span><br />'.$copyresult;
                        }
                    } else {
                        $discussion .= '<p class="LC_error">'.
                                       &mt('Unfortunately you will not be able to retrieve an archive of the discussion posts at this time, because there was a problem creating the zip file.').'</p>';
                    }
                }
            } else {
                $discussion .= '<p class="LC_error">'.
                               &mt('Unfortunately you will not be able to retrieve an archive of the discussion posts at this time, because there was a problem creating a manifest file.').'</p>';
            }
            return $discussion;
        }
    }
    if ($discussiononly) {
        my $now = time;
        my $attachnum = 0;
        my $currnewattach = [];
        my $currdelold = [];
        my $comment = '';
        my $subject = '';
        if ($env{'form.origpage'}) {
            &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['addnewattach','deloldattach','delnewattach','timestamp','idx','subject','comment']);
            $subject = &unescape($env{'form.subject'});
            $comment = &unescape($env{'form.comment'});
            my @keepold = ();
            &process_attachments($currnewattach,$currdelold,\@keepold);
            if (@{$currnewattach} > 0) {
                $attachnum += @{$currnewattach};
            }
        }
	if ((&discussion_open($status)) && ($outputtarget ne 'tex')) {
            if (($group ne '') && ($mode eq 'board')) {  
                if ((&check_group_priv($group,'pgd') eq 'ok') && 
                   ($ressymb =~ m{^bulletin___\d+___adm/wrapper/adm/\Q$cdom\E/\Q$cnum\E/\d+/bulletinboard$})) {
                    $discussion .=
			&postingform_display($mode,$ressymb,$now,$subject,
					     $comment,$outputtarget,$attachnum,
					     $currnewattach,$currdelold,
					     $group,$crstype);
                }
            } else {
                if (&Apache::lonnet::allowed('pch',$env{'request.course.id'}.
                    ($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:''))) {

	            $discussion.= 
		        &postingform_display($mode,$ressymb,$now,$subject,
					     $comment,$outputtarget,$attachnum,
					     $currnewattach,$currdelold,'',$crstype);
                } else {
                    $discussion.= '<span class="LC_feedback_link">'.
                                  &mt('This discussion is closed.').'</span>';
                }
            }
	}
        if (!(&discussion_open($status)) && ($outputtarget ne 'tex')) {
            $discussion.= '<span class="LC_feedback_link">'.
                          &mt('This discussion is closed.').'</span>';
        }
    } elsif ($outputtarget ne 'tex') {
        unless ($nofooter) {
            $discussion.='<div class="LC_feedback_link">';
            unless ($nodisclink) {
                if (&discussion_open($status) &&
                    &Apache::lonnet::allowed('pch',
    	                $env{'request.course.id'}.
	                ($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:''))) {
                    $discussion.= &send_feedback_link($ressymb);
                    if ($env{'request.role.adv'}) {
                        my $close = &Apache::lonnet::EXT('resource.0.discussend',$ressymb);
                        my $canvote = &Apache::lonnet::EXT('resource.0.discussvote',$ressymb);
                        if (defined($close) && $close ne '' && $close < time) {
                            if ($canvote eq 'notended') {
                                $discussion .= '&nbsp;'.&mt('(Posting and voting closed for [_1] roles)',
                                                            &Apache::lonnet::plaintext('st',$crstype));
                            } else {
                                $discussion .= '&nbsp;'.&mt('(Closed for [_1] roles)',
                                                            &Apache::lonnet::plaintext('st',$crstype));
                            }
                        }
                    }
	        } else {
                    $discussion.= '<span class="LC_feedback_link">'.&mt('This discussion is closed.').'</span>';
                }
            }
            unless ($nofdbklink) {
	        $discussion.= &send_message_link($ressymb);
            }
            $discussion.='</div>';
        }
    }
    return $discussion;
}

sub check_menucoll {
    my ($nofooter,$nodisclink,$nofdbklink);
    my ($menucoll,$deeplinkmenu,$menuref) = &Apache::loncommon::menucoll_in_effect();
    if ($menucoll) {
        if (ref($menuref) eq 'HASH') {
            if ($menuref->{'foot'} eq 'n') {
                $nofooter = 1;
            } else {
                unless ($menuref->{'disc'}) {
                    $nodisclink = 1;
                }
                unless ($menuref->{'fdbk'}) {
                    $nofdbklink = 1;
                }
            }
        }
    }
    return ($nofooter,$nodisclink,$nofdbklink);
}

sub can_see_hidden {
    my ($mode,$ressymb,$feedurl,$group,$cdom,$cnum,$crs) = @_;
    my $seehidden;
    if ($env{'request.course.id'}) {
        unless ($cdom ne '' && $cnum ne '') {
            $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
            $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
        }
        if ($crs eq '') {
            $crs = '/'.$env{'request.course.id'};
            if ($env{'request.course.sec'}) {
                $crs.='_'.$env{'request.course.sec'};
            }
            $crs=~s{_}{/}g;
        }
        if ($mode eq '') {
            $mode='board';
            if ($feedurl =~ /$LONCAPA::assess_re/) {
                $mode='problem';
            }
        }
        if (($group ne '') && ($mode eq 'board') &&
            ($ressymb =~ m{^bulletin___\d+\Q___adm/wrapper/adm/$cdom/$cnum/\E\d+/bulletinboard$})) {
            if (&check_group_priv($group,'dgp') eq 'ok') {
                $seehidden = 1;
            }
        } else {
            $seehidden=&Apache::lonnet::allowed('rin',$crs);
        }
    }
    return $seehidden;
}

sub discussion_link {
   my ($ressymb,$linktext,$cmd,$item,$flag,$prev,$adds,$title)=@_;
   my $link='/adm/feedback?inhibitmenu=yes&amp;modal=yes&amp;'.$cmd.'='.&escape($ressymb).':::'.$item;
   if ($flag) { $link .= '&amp;previous='.$prev; }
   if ($adds) { $link .= $adds; }
   my $width=600;
   my $height=600;
   if (($cmd eq 'hide') || ($cmd eq 'unhide') || ($cmd eq 'like') || ($cmd eq 'unlike')) {
       $width=300;
       $height=200;
   }
   return &Apache::loncommon::modal_link($link,$linktext,$width,$height,undef,undef,$title);
}


sub send_feedback_link {
    my ($ressymb) = @_;
    return '<span class="LC_feedback_link">'.
                 &discussion_link($ressymb,
                    '<img alt="" class="LC_noBorder" src="'.
                    &Apache::loncommon::lonhttpdurl('/adm/lonMisc/chat.gif').
                    '" /><span class="LC_menubuttons_inline_text">'.&mt('Post Discussion').'</span>',
                    'replydisc').
           '</span>';
}

sub send_message_link {
    my ($ressymb) = @_;
    my $output = '<span class="LC_message_link">'.
                 &discussion_link($ressymb,
                    '<img alt="" class="LC_noBorder" src="'.
                    &Apache::loncommon::lonhttpdurl('/res/adm/pages/feedback.png').
                    '" /><span class="LC_menubuttons_inline_text">'.&mt('Send Feedback').'</span>',
                    'sendmessageonly').
                 '</span>';
    return $output;
}

sub action_links_bar {
    my ($colspan,$ressymb,$visible,$newpostsflag,$group,$prevread,$markondisp,
        $seehidden) = @_;
    my $discussion = '<tr><td colspan="'.$colspan.'">'.
                     '<table width="100%"><tr>'.
                     '<td class="LC_disc_action_left">';
    my $escsymb=&escape($ressymb);
    if ($visible) {
        $discussion .= '<a href="/adm/feedback?cmd=threadedon&amp;symb='.$escsymb;
        if ($newpostsflag) {
            $discussion .= '&amp;previous='.$prevread;
        }
        $discussion .= &group_args($group);
        $discussion .='">'.&mt('Threaded View').'</a>&nbsp;&nbsp;'.
                      '<a href="/adm/feedback?cmd=threadedoff&amp;symb='.$escsymb;
        if ($newpostsflag) {
            $discussion .= '&amp;previous='.$prevread;
        }
        $discussion .= &group_args($group);
        $discussion .='">'.&mt('Chronological View').'</a>&nbsp;&nbsp;';

        my $otherviewurl='/adm/feedback?cmd=sortfilter&amp;symb='.$escsymb.'&amp;inhibitmenu=yes&amp;modal=yes';
        if ($newpostsflag) {
            $otherviewurl .= '&amp;previous='.$prevread;
        }
        $otherviewurl .= &group_args($group);
        $discussion .= &Apache::loncommon::modal_link($otherviewurl,&mt('Other Views ...'),800,340);
        $discussion .= '<br />';
    }
    $discussion .='<a href="/adm/feedback?export='.$escsymb;
    if ($newpostsflag) {
        $discussion .= '&amp;previous='.$prevread;
    }
    $discussion .= &group_args($group);
    $discussion .= '">'.&mt('Export').'</a>';
    if ($seehidden) {
        $discussion .= '&nbsp;&nbsp;';
        $discussion .='<a href="/adm/feedback?undeleteall='.$escsymb;
        if ($newpostsflag) {
            $discussion .= '&amp;previous='.$prevread;
        }
        $discussion .= &group_args($group);
        $discussion .= '">'.&mt('Undelete all deleted entries').'</a>';
    }
    $discussion.='</td>';
    if ($newpostsflag) {
        if (!$markondisp) {
            $discussion .='<td class="LC_disc_action_right"><a href="/adm/preferences?action=changediscussions';
            $discussion .= &group_args($group);
            $discussion .= '">'.
                           &mt('My general preferences on what is marked as NEW').
                           '</a><br /><a href="/adm/feedback?markread=1&amp;symb='.$escsymb;
            $discussion .= &group_args($group);
            $discussion .= '">'.&mt('Mark NEW posts no longer new').'</a></td>';
        } else {
            $discussion .= '<td>&nbsp;</td>';
        }
    } else {
        $discussion .= '<td>&nbsp;</td>';
    }
    $discussion .= '</tr></table></td></tr>';
    return $discussion;
}

sub postingform_display {
    my ($mode,$ressymb,$now,$subject,$comment,$outputtarget,$attachnum,
        $currnewattach,$currdelold,$group,$crstype) = @_;
    my $newattachmsg;
    my %lt = &Apache::lonlocal::texthash(
             'note' => 'Note: in anonymous discussion, your name is visible only to course faculty',
             'title' => 'Title',
             'podi' => 'Post Discussion',
             'poan' => 'Post Anonymous Discussion',
             'newa' => 'New attachments',
    );
    if ($crstype eq 'Community') {
        $lt{'note'} = &mt('Note: in anonymous discussion, your name is visible only to community facilitators');
    }
    my ($postingform,$textareaclass);
    if (&Apache::lonhtmlcommon::htmlareabrowser()) {
        $postingform = &Apache::lonhtmlcommon::htmlareaselectactive();
        $textareaclass = 'class="LC_richDefaultOff"';
        if ($env{'request.course.id'}) {
            unless (($env{'course.'.$env{'request.course.id'}.'.allow_limited_html_in_feedback'} =~ /^\s*yes\s*$/i) || ($env{'form.sendmessageonly'})) {
                undef($textareaclass);
            }
        }
    }
    $postingform .= (<<ENDDISCUSS);
<form action="/adm/feedback" method="post" name="mailform" enctype="multipart/form-data"> <input type="submit" name="discuss" value="$lt{'podi'}" />
<input type="submit" name="anondiscuss" value="$lt{'poan'}" /> <input type="hidden" name="symb" value="$ressymb" />
<input type="hidden" name="sendit" value="true" />
<input type="hidden" name="timestamp" value="$now" />
<a name="newpost"></a>
<font size="1">$lt{'note'}</font><br />
<b>$lt{'title'}:</b>&nbsp;<input type="text" name="subject" value="$subject" size="30" /><br />
<textarea name="comment" cols="80" rows="14" id="comment" $textareaclass>$comment</textarea>
ENDDISCUSS
    if ($env{'form.origpage'}) {
        $postingform .= '<input type="hidden" name="origpage" value="'.
                        $env{'form.origpage'}.'" />'."\n";
        foreach my $att (@{$currnewattach}) {
            $postingform .= '<input type="hidden" name="currnewattach" '.
                            'value="'.$att.'" />'."\n";
        }
    }
    if (exists($env{'form.ref'})) {
        $postingform .= '<input type="hidden" name="ref" value="'.
                        $env{'form.ref'}.'" />';
    }
    if ($group ne '') {
        $postingform .='<input type="hidden" name="group" value="'.$group.'" />';
    }
    my $blockblog = &Apache::loncommon::blocking_status('blogs');
    if (!$blockblog) {
        $postingform .= &add_blog_checkbox($crstype);
    }
    $postingform .= "</form>\n";
    $postingform .= &generate_attachments_button('',$attachnum,$ressymb,
                                                     $now,$currnewattach,
                                                     $currdelold,'',$mode,
                                                     $blockblog);
    if ((ref($currnewattach) eq 'ARRAY') && (@{$currnewattach} > 0)) {
        $newattachmsg = '<br /><b>'.$lt{'newa'}.'</b><br />';
        if (@{$currnewattach} > 1) {
             $newattachmsg .= '<ol>';
             foreach my $item (@{$currnewattach}) {
                $item =~ m#.*/([^/]+)$#;
                $newattachmsg .= '<li><a href="'.$item.'">'.$1.'</a></li>'."\n";
             }
             $newattachmsg .= '</ol>'."\n";
         } else {
             $$currnewattach[0] =~ m#.*/([^/]+)$#;
             $newattachmsg .= '<a href="'.$$currnewattach[0].'">'.$1.'</a><br />'."\n";
         }
    }
    $postingform .= $newattachmsg;
    $postingform .= &generate_preview_button();
    return $postingform;
}

sub build_posting_display {
    my ($usernamesort,$subjectsort,$namesort,$notshown,$newitem,$dischash,$shown,$alldiscussion,$imsitems,$imsfiles,$roleinfo,$discussionitems,$replies,$depth,$posters,$maxdepth,$visible,$newpostsflag,$current,$status,$viewgrades,$seeid,$seehidden,$canvote,$prevread,$sortposts,$ressymb,$readkey,$showunmark,$showonlyunread,$totposters,$rolefilter,$sectionpick,$grouppick,$classgroups,$statusfilter,$toggkey,$outputtarget,$anonhash,$anoncnt,$group) = @_;
    my @original=();
    my @index=();
    my $skip_group_check = 0;
    my $symb=&Apache::lonenc::check_decrypt($ressymb);
    my $escsymb=&escape($ressymb);
# These are the discussion contributions
    my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
			  $env{'course.'.$env{'request.course.id'}.'.domain'},
			  $env{'course.'.$env{'request.course.id'}.'.num'});
    my (%likes,%userlikes,%userunlikes,@theselikes,$oneplus,$twoplus,$oneminus,$twominus);
    my $thisuser=$env{'user.name'}.':'.$env{'user.domain'};
    if ($seeid || $canvote) {
# And these are the likes/unlikes
        %likes=&Apache::lonnet::dump('disclikes',
                          $env{'course.'.$env{'request.course.id'}.'.domain'},
                          $env{'course.'.$env{'request.course.id'}.'.num'},
                          '^'.$symb.':');
# Array with likes to figure out averages, etc.
        @theselikes=();
# Hashes containing likes and unlikes for this user.
        %userlikes=();
        %userunlikes=();
    }
# Is the user allowed to see the real name behind anonymous postings?
    my $see_anonymous = 
	&Apache::lonnet::allowed('rin',$env{'request.course.id'}.($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:''));

    if ((@{$grouppick} == 0) || (grep(/^all$/,@{$grouppick}))) {
        $skip_group_check = 1;
    }
# Deletions and hiddens are just lists. Split them up into a hash for quicker lookup
    my (%deletions,%hiddens);
    if ($contrib{'deleted'}) {
       my $deleted = $contrib{'deleted'};
       $deleted =~ s/^\.//;
       $deleted =~ s/\.$//;
       %deletions = map { $_ => 1 } (split(/\.\./,$deleted));
    }
    if ($contrib{'hidden'}) {
       my $hidden = $contrib{'hidden'};
       $hidden =~ s/^\.//;
       $hidden =~ s/\.$//;
       %hiddens = map { $_ => 1 } (split(/\.\./,$hidden));
    }
# Versions if store/restore are used to actually store the messages. 
    if ($contrib{'version'}) {
        my $oldest = $contrib{'1:timestamp'};
        if ($prevread eq '0') {
            $prevread = $oldest-1;
        }
        my ($skiptest,$rolematch,$roleregexp,$secregexp,$statusregexp);
        if ($sortposts) {
            ($skiptest,$roleregexp,$secregexp,$statusregexp) = 
                     &filter_regexp($rolefilter,$sectionpick,$statusfilter);
            $rolematch = $roleregexp.':'.$secregexp.':'.$statusregexp;
        }
        my %votestyle;
        if ($seeid || $canvote) {
# We need to go through this twice, first to get the likes/dislikes, then to actually build the display
            for (my $id=1;$id<=$contrib{'version'};$id++) {
                my $idx=$id;
                next if ($contrib{$idx.':deleted'});
                next if ($contrib{$idx.':hidden'});
                unless ((($hiddens{$idx}) && (!$seehidden)) || ($deletions{$idx}) || (!$contrib{$idx.':message'})) {
                    push(@theselikes,$likes{$symb.':'.$idx.':likes'});
                    if ($likes{$symb.':'.$idx.':likes'} ne '') {
                        if (ref($likes{$symb.':'.$idx.':likers'}) eq 'HASH') {
                            if (exists($likes{$symb.':'.$idx.':likers'}{$thisuser})) {
                                $userlikes{$idx} = 1;
                            }
                        }
                        if (ref($likes{$symb.':'.$idx.':unlikers'}) eq 'HASH') {
                            if (exists($likes{$symb.':'.$idx.':unlikers'}{$thisuser})) {
                                $userunlikes{$idx} = 1;
                            }
                        }
                    }
                }
            }
# Figure out average likes and standard deviation if there are enough 
# discussions to warrant that
            my $ave=0;
            my $stddev=10000;
            if ($#theselikes>1) {
                my $sum=0;
                my $num=$#theselikes+1;
                foreach my $thislike (@theselikes) {
                    $sum+=$thislike;
                }
                $ave=$sum/$num;
                my $sumsq=0;
                foreach my $thislike (@theselikes) {
                    $sumsq+=($thislike-$ave)*($thislike-$ave);
                }
                $stddev=sqrt($sumsq/$num);
            }
# Now we know the average likes $ave and the standard deviation $stddev
# Get the boundaries for markup
            $oneplus=$ave+$stddev;
            $twoplus=$ave+2.*$stddev;
            $oneminus=$ave-$stddev;
            $twominus=$ave-2.*$stddev;
            if ($#theselikes>1) {
                foreach my $class ('twoplus','oneplus','zero','oneminus','twominus') {
                    my $fontstyle = $env{'course.'.$env{'request.course.id'}.'.discussion_post_fonts_'.$class};
                    if ($fontstyle ne '') {
                        my ($size,$weight,$style,$other) = split(/,/,$fontstyle);
                        if ($size ne '') {
                            $votestyle{$class} .= 'font-size: '.$size.';';
                        }
                        if ($weight ne '') {
                            $votestyle{$class} .= 'font-weight: '.$weight.';';
                        }
                        if ($style ne '') {
                            $votestyle{$class} .= 'font-style: '.$style.';';
                        }
                        if ($other ne '') {
                            $votestyle{$class} .= $other;
                        }
                        if ($votestyle{$class} ne '') {
                            $votestyle{$class} = 'style="'.$votestyle{$class}.'"';
                        }
                    }
                }
            }
        }
#
# This is now the real loop. Go through all entries, pick up what we need
#
	for (my $id=1;$id<=$contrib{'version'};$id++) {
	    my $idx=$id;
            next if ($contrib{$idx.':deleted'});
            next if ($contrib{$idx.':hidden'});
# If we get here, we are actually going to display the message - we don't know where and we don't know if we display
# previous edits, but it counts as one entry
            my $posttime = $contrib{$idx.':timestamp'};
            if ($prevread <= $posttime) {
                $$newpostsflag = 1;
            }
            my $studenthidden=($contrib{'studenthidden'}=~/\.$idx\./);
	    my $origindex='0.';
            my $numoldver=0;
	    if ($contrib{$idx.':replyto'}) {
                if ( ((!$env{'environment.unthreadeddiscussion'}) && ($sortposts eq '')) || 
                     ($sortposts eq 'thread') || ($outputtarget eq 'export')) {
# this is a follow-up message
		    $original[$idx]=$original[$contrib{$idx.':replyto'}];
		    $$depth[$idx]=$$depth[$contrib{$idx.':replyto'}]+1;
		    $origindex=$index[$contrib{$idx.':replyto'}];
		    if ($$depth[$idx]>$$maxdepth) { $$maxdepth=$$depth[$idx]; }
                } else {
                    $original[$idx]=0;
                    $$depth[$idx]=0;
                }
	    } else {
# this is an original message
		$original[$idx]=0;
		$$depth[$idx]=0;
	    }
	    if ($$replies[$$depth[$idx]]) {
		$$replies[$$depth[$idx]]++;
	    } else {
		$$replies[$$depth[$idx]]=1;
	    }
            unless ((($hiddens{$idx}) && (!$seehidden)) || ($deletions{$idx})) {
		$$visible++;
                if ($contrib{$idx.':history'}) {
                    if ($contrib{$idx.':history'} =~ /:/) {
                        my @oldversions = split(/:/,$contrib{$idx.':history'});
                        $numoldver = @oldversions;
                    } else {
                        $numoldver = 1;
                    } 
                }
                $$current = $numoldver;
		my %messages = ();
                my %subjects = ();
                my %attachtxt = ();
                my %allattachments = ();
                my ($screenname,$plainname,$showaboutme);
                my $sender = &mt('Anonymous');
# Anonymous users getting number within a discussion
# Since idx is in static order, this should give the same sequence every time. 
		my $key=$contrib{$idx.':sendername'}.'@'.$contrib{$idx.':senderdomain'};
		unless ($$anonhash{$key}) {
                    $anoncnt++;
		    $$anonhash{$key}=&mt('Anonymous').' '.$anoncnt;
		}
                my ($message,$subject,$vgrlink,$ctlink);
                &get_post_contents(\%contrib,$idx,$seeid,$seehidden,$outputtarget,\%messages,\%subjects,\%allattachments,\%attachtxt,$imsfiles,\$screenname,\$plainname,\$showaboutme,$numoldver);


# Set up for sorting by subject
                unless ($outputtarget eq 'export') {
                    $message=$messages{$numoldver};
                    $message.=$attachtxt{$numoldver};
                    $subject=$subjects{$numoldver};
                    if ($message) {
	  	        if ($hiddens{$idx}) {
			    $message='<font color="#888888">'.$message.'</font>';
                            if ($studenthidden) {
                                $message .='<br /><br />Deleted by poster (student).';
                            }
		        }

                        if ($subject eq '') {
                           if (defined($$subjectsort{'__No subject'})) {
                               push(@{$$subjectsort{'__No subject'}}, $idx);
                           } else {
                               @{$$subjectsort{'__No subject'}} = ("$idx");
                           }
                        } else {
                            if (defined($$subjectsort{$subject})) {
                               push(@{$$subjectsort{$subject}}, $idx);
                            } else {
                               @{$$subjectsort{$subject}} = ("$idx");
                            }
                        }
		        if (!$contrib{$idx.':anonymous'} || $see_anonymous) {
                            if ($showaboutme) {
                                $sender = &Apache::loncommon::aboutmewrapper(
                                              $plainname,
                                              $contrib{$idx.':sendername'},
                                              $contrib{$idx.':senderdomain'});
                            } else {
                                $sender = $plainname;
                            }
                            if ($see_anonymous) {
                                $sender .= ' ('.$contrib{$idx.':sendername'}.':'.
					   $contrib{$idx.':senderdomain'}.')';
                            }
                            $sender = '<b>'.$sender.'</b>';
			    if ($contrib{$idx.':anonymous'}) {
			        $sender.=' <font color="red"><b>['.$$anonhash{$key}.']</b></font> '.
				    $screenname;
			    }
			    if ($see_anonymous) {
				$sender.=&Apache::loncommon::student_image_tag($contrib{$idx.':senderdomain'},$contrib{$idx.':sendername'});
			    }
# Set up for sorting by domain, then username
                            unless (defined($$usernamesort{$contrib{$idx.':senderdomain'}})) {
                                %{$$usernamesort{$contrib{$idx.':senderdomain'}}} = ();
                            }
                            if (defined($$usernamesort{$contrib{$idx.':senderdomain'}}{$contrib{$idx.':sendername'}})) {
                                push(@{$$usernamesort{$contrib{$idx.':senderdomain'}}{$contrib{$idx.':sendername'}}}, $idx);
                            } else {
                                @{$$usernamesort{$contrib{$idx.':senderdomain'}}{$contrib{$idx.':sendername'}}} = ("$idx");
                            }
# Set up for sorting by last name, then first name
                            my %names = &Apache::lonnet::get('environment',
                                 ['firstname','lastname'],$contrib{$idx.':senderdomain'},
                                  ,$contrib{$idx.':sendername'});
                            my $lastname = $names{'lastname'};
                            my $firstname = $names{'firstname'};
                            if ($lastname eq '') {
                                $lastname = '_';
                            }
                            if ($firstname eq '') {
                                $firstname = '_';
                            }
                            unless (defined($$namesort{$lastname})) {
                                %{$$namesort{$lastname}} = ();
                            }
                            if (defined($$namesort{$lastname}{$firstname})) {
                                push(@{$$namesort{$lastname}{$firstname}}, $idx);
                            } else {
                                @{$$namesort{$lastname}{$firstname}} = ("$idx");
                            }
                            if ($outputtarget ne 'tex') {
# Add karma stars
                                my $karma=&userkarma($contrib{$idx.':sendername'},$contrib{$idx.':senderdomain'});
                                for (my $i=1;$i<=$karma;$i++) {
                                    $sender.='<img border="0" src="/res/adm/pages/star.gif" alt="'.&mt('Contributor Kudos').'" />';
                                }
# Can people edit this?
                                if (&editing_allowed($escsymb.':::'.$idx,$group)) {
                                    if (($env{'user.domain'} eq $contrib{$idx.':senderdomain'}) && ($env{'user.name'} eq $contrib{$idx.':sendername'})) {
                                        $sender.=' '.
                                         &discussion_link($ressymb,&mt('Edit'),'editdisc',$idx,$$newpostsflag,$prevread,&group_args($group));
                                        unless ($seehidden) {
                                            my $grpargs = &group_args($group);
                                            $sender.=" <a href=\"javascript:verifydelete('studentdelete','$escsymb','$idx','$$newpostsflag','$prevread','$grpargs')";
                                            $sender .= '">'.&mt('Delete').'</a>';
                                        }
                                    }
                                }
			        if ($seehidden) {
			            if ($hiddens{$idx}) {
                                        unless ($studenthidden) {
 		                           $sender.=' '.
                                            &discussion_link($ressymb,&mt('Make Visible'),'unhide',$idx,$$newpostsflag,$prevread,&group_args($group));
                                        }
			            } else {
                                        $sender.=' '.
                                         &discussion_link($ressymb,&mt('Hide'),'hide',$idx,$$newpostsflag,$prevread,&group_args($group));
			            }
                                    my $grpargs = &group_args($group);
			            $sender.= 
                                        " <a href=\"javascript:verifydelete('seeiddelete','$escsymb','$idx','$$newpostsflag','$prevread','$grpargs')\">";
                                    $sender .= &mt('Delete').'</a>';
                                }
                            }
                        } else {
			    if ($screenname) {
			        $sender='<i>'.$screenname.'</i>';
			    } else {
				$sender='<i>'.$$anonhash{$key}.'</i>';
			    }
                            $sender = '<b>'.$sender.'</b>';
# Set up for sorting by domain, then username for anonymous
                            unless (defined($$usernamesort{'__anon'})) {
                                %{$$usernamesort{'__anon'}} = ();
                            }
                            if (defined($$usernamesort{'__anon'}{'__anon'})) {
                                push(@{$$usernamesort{'__anon'}{'__anon'}}, $idx);
                            } else {
                                @{$$usernamesort{'__anon'}{'__anon'}} = ("$idx");
                            }
# Set up for sorting by last name, then first name for anonymous
                            unless (defined($$namesort{'__anon'})) {
                                %{$$namesort{'__anon'}} = ();
                            }
                            if (defined($$namesort{'__anon'}{'__anon'})) {
                                push(@{$$namesort{'__anon'}{'__anon'}}, $idx);
                            } else {
                                @{$$namesort{'__anon'}{'__anon'}} = ("$idx");
                            }
		        }
                        if ($outputtarget ne 'tex') {
		            if (&discussion_open($status)) {
                                if (($group ne '') && 
                                    (&check_group_priv($group,'pgd') eq 'ok')) {
                                     $sender.=' '.
                                         &discussion_link($ressymb,&mt('Reply'),'replydisc',$idx,$$newpostsflag,$prevread,&group_args($group));
                                } elsif (&Apache::lonnet::allowed('pch', 
				     $env{'request.course.id'}.
				     ($env{'request.course.sec'}?'/'.
                                      $env{'request.course.sec'}:''))) {
			             $sender.=' '.
                                         &discussion_link($ressymb,&mt('Reply'),'replydisc',$idx,$$newpostsflag,$prevread);
                                }
                            }
		            if ($viewgrades) {
			        $vgrlink=&Apache::loncommon::submlink(&mt('Submissions'),
                                $contrib{$idx.':sendername'},$contrib{$idx.':senderdomain'},$ressymb);
		            }
                            if ($$dischash{$readkey}=~/\.$idx\./) { 
                                $ctlink = '<label><b>'.&mt('Mark unread').'?</b>&nbsp;<input type="checkbox" name="postunread_'.$idx.'" /></label>';
                            } else {
                                $ctlink = '<label><b>'.&mt('Mark read').'?</b>&nbsp;<input type="checkbox" name="postread_'.$idx.'" /></label>';
                            }
                        }
                    }
#figure out at what position this needs to print
                }
                if ($outputtarget eq 'export' || $message) {
		    my $thisindex=$idx;
		    if ( ((!$env{'environment.unthreadeddiscussion'}) && ($sortposts eq '')) || 
                         ($sortposts eq 'thread') || ($outputtarget eq 'export')) {
			$thisindex=$origindex.substr('00'.$$replies[$$depth[$idx]],-2,2);
		    }
		    $$alldiscussion{$thisindex}=$idx;
                    $$shown{$idx} = 0;
                    $index[$idx]=$thisindex;
                }
                if ($outputtarget eq 'export') {
                    %{$$imsitems{$idx}} = ();
                    $$imsitems{$idx}{'isvisible'}='true';
                    if ($hiddens{$idx}) {
                        $$imsitems{$idx}{'isvisible'}='false';
                    }
                    $$imsitems{$idx}{'title'}=$subjects{$numoldver};
                    $$imsitems{$idx}{'message'}=$messages{$numoldver};
                    $$imsitems{$idx}{'attach'}=$attachtxt{$numoldver};
                    $$imsitems{$idx}{'timestamp'}=$contrib{$idx.':timestamp'};
                    $$imsitems{$idx}{'sender'}=$plainname.' ('.
                                         $contrib{$idx.':sendername'}.':'.
                                         $contrib{$idx.':senderdomain'}.')';
                    $$imsitems{$idx}{'isanonymous'}='false';
                    if ($contrib{$idx.':anonymous'}) {
                        $$imsitems{$idx}{'isanonymous'}='true';
                    }
                    $$imsitems{$idx}{'currversion'}=$numoldver;
                    %{$$imsitems{$idx}{'allattachments'}}=%allattachments;
                    unless ($messages{$numoldver} eq '' && $attachtxt{$numoldver} eq '') {
                        $$shown{$idx} = 1;
                    }
                } else {
                    if ($message) {
                        my $spansize = 2;
                        my ($uname,$udom);
                        if ($showonlyunread && $prevread > $posttime) {
                            $$notshown{$idx} = 1;
                        } elsif ($showunmark && $$dischash{$readkey}=~/\.$idx\./) {
                            $$notshown{$idx} = 1;
                        } else {
# apply filters
                            $uname = $contrib{$idx.':sendername'};
                            $udom = $contrib{$idx.':senderdomain'};
                            my $poster = $uname.':'.$udom;
                            if ($env{'form.totposters'} ne '') {
                                if ($totposters == 0) {
                                    $$shown{$idx} = 0;
                                } elsif ($totposters > 0) {
                                    if (grep/^$poster$/,@{$posters}) {
                                        $$shown{$idx} = 1;
                                    }
                                }
                            } elsif ($sortposts) {
                                if ($skiptest) {
                                    $$shown{$idx} = 1;
                                } else {
                                    foreach my $role (@{$$roleinfo{$poster}}) {
                                        if ($role =~ /^cc:/) {
                                            my $cc_regexp = $roleregexp.':[^:]*:'.$statusregexp;
                                            if ($role =~ /$cc_regexp/) {
                                                $$shown{$idx} = 1;
                                                last;
                                            }
                                        } elsif ($role =~ /^$rolematch$/) {
                                            $$shown{$idx} = 1;
                                            last;
                                        }
                                    }
                                }
                                if ($$shown{$idx} && !$skip_group_check) {
                                    my $showflag = 0;
                                    if (ref($$classgroups{$poster}{active}) eq 'HASH') {
                                        foreach my $grp (@{$grouppick}) {
                                            if (grep/^\Q$grp\E$/,
                                 keys(%{$$classgroups{$poster}{active}})) {
                                                $showflag = 1;
                                                last;
                                            }
                                        }
                                    }
                                    if ($showflag) {
                                        $$shown{$idx} = 1;
                                    } else {
                                        $$shown{$idx} = 0;
                                    }
                                }
                            } else {
                                $$shown{$idx} = 1;
                            }
                        }
                        unless ($$notshown{$idx} == 1) {
                            if ($prevread > 0 && $prevread <= $posttime) {
                                $$newitem{$idx} = 1;
                                $$discussionitems[$idx] .= '<font color="#FF0000"><b>'.&mt('NEW').'&nbsp;&nbsp;</b></font>';
                            } else {
                                $$newitem{$idx} = 0;
                            }
                            $$discussionitems[$idx] .= '<b>'.$subject.'</b>&nbsp;&nbsp;'.
                                $sender.' '.$vgrlink.' ('.
                                &Apache::lonlocal::locallocaltime($posttime).')';
                            if ($$dischash{$toggkey}) {
                                $$discussionitems[$idx].='&nbsp;&nbsp;'.$ctlink;
                            }
                            my $thislikes=$likes{$symb.':'.$idx.':likes'};
                            my $likestyle;
                            if ($seeid || $canvote) {
# Figure out size based on likes
                                my $class = 'zero';
                                my $thislikes=$likes{$symb.':'.$idx.':likes'};
                                if ($thislikes>$twoplus) {
                                    $class = 'twoplus';
                                } elsif ($thislikes>$oneplus) {
                                    $class = 'oneplus';
                                }
                                if ($thislikes<$twominus) {
                                    $class = 'twominus';
                                } elsif ($thislikes<$oneminus) {
                                    $class = 'oneminus';
                                }
                                $likestyle = $votestyle{$class};
                            }
# Actually glue in the message itself
                            $$discussionitems[$idx].= '<br /><blockquote>'.
                                    "<div $likestyle>".
                                    $message.
                                    '</div></blockquote>';
                            if ($canvote) {
                                my $ownpost;
                                if (($uname eq $env{'user.name'}) &&
                                    ($udom eq $env{'user.domain'})) {
                                    $ownpost = 1;
                                }   
# Put in the like and unlike buttons
                                if ($ownpost || (($hiddens{$idx}) && ($seehidden))) { 
                                    my $novote;
                                    if ($ownpost) { 
                                        $novote = &mt('No voting for your own posts.');
                                    } else {
                                        $novote = &mt('No voting for hidden posts.');
                                    }
                                    &html_escape(\$novote);
                                    $$discussionitems[$idx].=
                                        '<a href="javascript:alert('."'$novote'".');" style="text-decoration: none;">'.
                                        '<img border="0" src="/res/adm/pages/thumbsup_novote.png" alt="'.$novote.'" />&nbsp;'.
                                        '<img border="0" src="/res/adm/pages/thumbsdown_novote.png" alt="'.$novote.'" /></a>'; 

                                } else {
                                    if ($userlikes{$idx}) {
                                        $$discussionitems[$idx].='<img border="0" src="/res/adm/pages/thumbsup_gray.png" alt="'.&mt('You like this posting').'" />';
                                    } else {
                                        $$discussionitems[$idx].='&nbsp;'.&discussion_link($ressymb,'<img border="0" src="/res/adm/pages/thumbsup.png" alt="'.&mt('Like').'" />','like',$idx,$$newpostsflag,$prevread,&group_args($group),&mt("Like this posting"));
                                    }
                                    if ($userunlikes{$idx}) {
                                        $$discussionitems[$idx].='<img border="0" src="/res/adm/pages/thumbsdown_gray.png" alt="'.&mt('You unlike this posting').'" />';
                                    } else {
                                        $$discussionitems[$idx].='&nbsp;'.&discussion_link($ressymb,'<img border="0" src="/res/adm/pages/thumbsdown.png" alt="'.&mt('Unlike').'" />','unlike',$idx,$$newpostsflag,$prevread,&group_args($group),&mt("Unlike this posting"));
                                    }
                                }
                            }
                            if ($seeid || $canvote) {
                                my $thislikes=$likes{$symb.':'.$idx.':likes'};
                                if ($thislikes>0) {
                                    $$discussionitems[$idx].='&nbsp;('.&mt("[_1] likes",$thislikes).')';
                                } elsif ($thislikes<0) {
                                    $$discussionitems[$idx].='&nbsp;('.&mt("[_1] unlikes",abs($thislikes)).')';
                                }
                            }
# If there is any history to this post, inform the reader
                            if ($contrib{$idx.':history'}) {
                                my @postversions = ();
                                $$discussionitems[$idx] .= '&nbsp;&nbsp;'.&mt('This post has been edited by the author.');
                                if ($seehidden) {
                                    $$discussionitems[$idx] .= '&nbsp;&nbsp;'.
                                         &discussion_link($ressymb,&mt('Display all versions'),'allversions',$idx,$$newpostsflag,$prevread,&group_args($group));
                                }
                                $$discussionitems[$idx].='<br/>'.&mt('Earlier version(s) were posted on: ');
                                if ($contrib{$idx.':history'} =~ m/:/) {
                                    @postversions = split(/:/,$contrib{$idx.':history'});
                                } else {
                                    @postversions = ("$contrib{$idx.':history'}");
                                }
                                for (my $i=0; $i<@postversions; $i++) {
                                    my $version = $i+1;
                                    $$discussionitems[$idx] .= '<b>'.$version.'.</b> - '.&Apache::lonlocal::locallocaltime($postversions[$i]).'  ';
                                }
                            }
# end of unless ($$notshown ...)
                        }
# end of if ($message) ...
                    }
# end of the else-branch of target being export
                }
# end of unless hidden or deleted
            }
# end of the loop over all discussion entries
	}
# end of "if there actually are any discussions
    }
# end of subroutine "build_posting_display" 
}

sub filter_regexp {
    my ($rolefilter,$sectionpick,$statusfilter) = @_;
    my ($roleregexp,$secregexp,$statusregexp);
    my $skiptest = 1;
    if (@{$rolefilter} > 0) {
        my @okrolefilter = ();
        foreach my $role (@{$rolefilter}) {
            unless ($role eq '') {
                push(@okrolefilter, $role);
            }
        }
        if (@okrolefilter > 0) {
            if (grep/^all$/,@okrolefilter) {
                $roleregexp='[^:]+';
            } else {
                if (@okrolefilter == 1) {
                    $roleregexp=$okrolefilter[0];
                } else {
                    $roleregexp='('.join('|',@okrolefilter).')';
                }
                $skiptest = 0;
            }
        }
    }
    if (@{$sectionpick} > 0) {
        my @oksectionpick = ();
        foreach my $sec (@{$sectionpick}) {
            unless ($sec eq '') {
                 push(@oksectionpick, $sec);
            }
        }
        if ((@oksectionpick > 0) && (!grep/^all$/,@oksectionpick)) {
            if (@oksectionpick == 1) {
                $secregexp = $oksectionpick[0];
            } else {
                $secregexp .= '('.join('|',@oksectionpick).')';
            }
            $skiptest = 0;
        } else {
            $secregexp .= '[^:]*';
        }
    }

    if (defined($statusfilter) && $statusfilter ne '') {
        if ($statusfilter eq 'all') {
            $statusregexp = '[^:]+';
        } else {
            $statusregexp = $statusfilter;
            $skiptest = 0;
        }
    }
    return ($skiptest,$roleregexp,$secregexp,$statusregexp);
}


sub get_post_contents {
    my ($contrib,$idx,$seeid,$seehidden,$type,$messages,$subjects,$allattachments,$attachtxt,$imsfiles,$screenname,$plainname,$showaboutme,$numver) = @_;
    my $discussion = '';
    my $start=$numver;
    my $end=$numver + 1;
    %{$$imsfiles{$idx}}=();
    if ($type eq 'allversions') {
       unless($seehidden) {
           $discussion=&mt('You do not have privileges to view all versions of posts.').' '.&mt('Please select a different role.');
           return $discussion;
       } 
    }
#    $$screenname=&Apache::loncommon::screenname(
#                                        $$contrib{$idx.':sendername'},
#                                        $$contrib{$idx.':senderdomain'});
    $$plainname=&Apache::loncommon::nickname(
                                        $$contrib{$idx.':sendername'},
                                        $$contrib{$idx.':senderdomain'});
    $$screenname=$$contrib{$idx.':screenname'};
    $$showaboutme = &Apache::lonnet::usertools_access($$contrib{$idx.':sendername'},
                                                      $$contrib{$idx.':senderdomain'},
                                                      'aboutme');
    my $sender = $$plainname;
    if ($$showaboutme) {
        $sender = &Apache::loncommon::aboutmewrapper(
                                 $$plainname,
                                 $$contrib{$idx.':sendername'},
                                 $$contrib{$idx.':senderdomain'});
    }
    if ($seeid) {
        $sender .= ' ('.$$contrib{$idx.':sendername'}.':'.
                   $$contrib{$idx.':senderdomain'}.')';
    }
    my $attachmenturls = $$contrib{$idx.':attachmenturl'};
    my @postversions = ();
    if ($type eq 'allversions' || $type eq 'export') {
        $start = 0;
        if ($$contrib{$idx.':history'}) {
	    @postversions = split(/:/,$$contrib{$idx.':history'});
        }
        &get_post_versions($messages,$$contrib{$idx.':message'},1);
        &get_post_versions($subjects,$$contrib{$idx.':subject'},1);
        push(@postversions,$$contrib{$idx.':timestamp'});
        $end = @postversions;
    } else {
        &get_post_versions($messages,$$contrib{$idx.':message'},1,$numver);
        &get_post_versions($subjects,$$contrib{$idx.':subject'},1,$numver);
    }

    if ($$contrib{$idx.':anonymous'}) {
        $sender.=' ['.&mt('anonymous').'] '.$$screenname;
    }
    if ($type eq 'allversions') {
        $discussion=('<b>'.$sender.'</b><br /><ul>');
    }
    for (my $i=$start; $i<$end; $i++) {
        my ($timesent,$attachmsg);
        my %currattach = ();
        $timesent = &Apache::lonlocal::locallocaltime($postversions[$i]);
        unless (&contains_block_html($messages->{$i})) {
            &newline_to_br(\$messages->{$i});
        }
        $$messages{$i}=&Apache::lontexconvert::msgtexconverted($$messages{$i});
        $$subjects{$i}=~s/\n/\<br \/\>/g;
        $$subjects{$i}=&Apache::lontexconvert::msgtexconverted($$subjects{$i});
        if ($attachmenturls) {
            &extract_attachments($attachmenturls,$idx,$i,\$attachmsg,$allattachments,\%currattach);
        }
        if ($type eq 'export') {
            $$imsfiles{$idx}{$i} = '';
            if ($attachmsg) {
                $$attachtxt{$i} = '<br />'.&mt('Attachments').':<br />';
                foreach my $key (sort(keys(%currattach))) {
                    if ($$allattachments{$key}{'filename'} =~ m-^/uploaded/([^/]+/[^/]+)(/feedback)?(/?\d*)/([^/]+)$-) {
                        my $fname = $1.$3.'/'.$4;
                        $$imsfiles{$idx}{$i} .= '<file href="'.$fname.'" />'."\n";
                        $$attachtxt{$i}.= '<a href="'.$fname.'">'.$4.'</a><br />';
                    }
                }
            }
        } else {
            if ($attachmsg) {
                $$attachtxt{$i} = '<br />'.&mt('Attachments').':'.$attachmsg.'<br />';
            } else {
                $$attachtxt{$i} = '';
            }
        }
        if ($type eq 'allversions') {
            $discussion.= <<"END";
<li><b>$$subjects{$i}</b>, $timesent<br />
$$messages{$i}<br />
$$attachtxt{$i}</li>
END
        }
    }
    if ($type eq 'allversions') {
        $discussion.='</ul>';
        return $discussion;
    } else {
        return;
    }
}

sub replicate_attachments {
    my ($attachrefs,$tempexport) = @_;
    my $response;
    foreach my $id (keys(%{$attachrefs})) {
        if ($$attachrefs{$id}{'filename'} =~ m-^/uploaded/([^/]+)/([^/]+)(/feedback)?(/?\d*)/([^/]+)$-) {
            my $path = $tempexport;
            my $tail = $1.'/'.$2.$4;
            my @extras = split(/\//,$tail);
            my $destination = $tempexport.'/'.$1.'/'.$2.$4.'/'.$5;
            if (!-e $destination) {
                my $i= 0;
                while ($i<@extras) {
                    $path .= '/'.$extras[$i];
                    if (!-e $path) {
                        mkdir($path,0700);
                    }
                    $i ++;
                }
                my ($content,$rtncode);
                my $uploadreply = &Apache::lonnet::getuploaded('GET',$$attachrefs{$id}{'filename'},$1,$2,$content,$rtncode);
                if ($uploadreply eq 'ok') {
                    my $attachcopy;
                    if ($attachcopy = Apache::File->new('>'.$destination)) {
                        print $attachcopy $content;
                        close($attachcopy);
                    } else {
                        $response .= &mt('Error copying file attachment - [_1] to IMS package',$5).': '.$!.'<br />'."\n";
                    }
                } else {
                    &Apache::lonnet::logthis("Replication of attachment failed when building IMS export of discussion posts - domain: $1, course: $2, file: $$attachrefs{$id}{'filename'} -error: $rtncode");
                    $response .= &mt('Error copying file attachment - [_1] to IMS package: ',$5).$rtncode.'<br />'."\n";
                }
            }
        }
    }
    return $response;
}

sub mail_screen {
  my ($r,$feedurl,$options,$caller_symb,$attachmaxtext) = @_;
  if (exists($env{'form.origpage'})) {
      &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['subject','comment','currnewattach','addnewattach','deloldattach','delnewattach','timestamp','idx','anondiscuss','discuss','blog','group','ref']);
  }

  my %lt = &Apache::lonlocal::texthash(
            'myqu' => 'Question/comment/feedback:',
            'reta' => 'Retained attachments',
            'atta' => 'Attachment',
           );
  if ($env{'form.editdisc'} || $env{'form.replydisc'}){
      $lt{'myqu'} = &mt('Post Discussion');
  }
  my $restitle = &get_resource_title($caller_symb,$feedurl);
  my $quote='';
  my $subject = '';
  my $comment = '';
  my $prevtag = '';
  my $parentmsg = '';
  my ($symb,$idx,$attachmenturls);
  my $numoldver = 0;
  my $attachmsg = '';
  my $newattachmsg = '';
  my @currnewattach = ();
  my @currdelold = ();
  my @keepold = ();
  my %attachments = ();
  my %currattach = ();
  my $attachnum = 0;
  my $anonchk = (<<END);
  function anonchk() {
      for (var i=0; i < document.mailform.discuss.length; i++) {
	  if (document.mailform.discuss[i].checked) {
	      document.attachment.discuss.value = 
		  document.mailform.discuss[i].value;
	  }
      }
      if (document.mailform.blog.checked) {
	  document.attachment.blog.value = 1;
      }
     return
   }
END
  my $anonscript;
  if (exists($env{'form.origpage'})) {
      $anonscript = (<<END);
  function setposttype() {
      var disc = "$env{'form.discuss'}";
      for (var i=0; i < document.mailform.discuss.length; i++) {
	  if (disc == document.mailform.discuss[i].value) {
	      document.mailform.discuss[i].checked = 1;
	  }
      }
      var blog = "$env{'form.blog'}";
      if (blog == 1) {
          document.mailform.blog.checked=1;
      }
      return
  }
END
  } else {
      $anonscript = (<<END);
  function setposttype() {
      return
  }
END
  }
  if (($env{'form.replydisc'}) || ($env{'form.editdisc'})) {
      if ($env{'form.replydisc'}) {
          ($symb,$idx)=split(/\:\:\:/,$env{'form.replydisc'});
      } else {
          ($symb,$idx)=split(/\:\:\:/,$env{'form.editdisc'});
      }
      my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
					   $env{'course.'.$env{'request.course.id'}.'.domain'},
					   $env{'course.'.$env{'request.course.id'}.'.num'});
      unless (($contrib{'hidden'}=~/\.$idx\./) || ($contrib{'deleted'}=~/\.$idx\./)) {
          my $numoldver = 0;
          if ($contrib{$idx.':history'}) {
              if ($contrib{$idx.':history'} =~ /:/) {
                  my @oldversions = split(/:/,$contrib{$idx.':history'});
                  $numoldver = @oldversions;
              } else {
                  $numoldver = 1;
              }
          }
          if ($idx > 0) {
              my (%msgversions,%subversions,$htmldecode);
              $htmldecode = 0;
              if ($env{'form.replydisc'}) {
                  $htmldecode = 1;
              }
              &get_post_versions(\%msgversions,$contrib{$idx.':message'},0,$numoldver);
              &get_post_versions(\%subversions,$contrib{$idx.':subject'},$htmldecode,
                                 $numoldver);
              $subject = $subversions{$numoldver};
              if ($env{'form.replydisc'}) {
                  $quote = $msgversions{$numoldver};
                  $subject = &HTML::Entities::encode(&mt('Re: ').$subject,'<>&"');
              } else {
                  $comment = $msgversions{$numoldver};
              }
          }
          if ($env{'form.editdisc'}) {
              $attachmenturls = $contrib{$idx.':attachmenturl'};
              if (defined($contrib{$idx.':replyto'})) {
                  $parentmsg = $contrib{$idx.':replyto'};
              }
              unless (exists($env{'form.origpage'})) {
                  my $anonflag = 'nonanon';
                  if ($contrib{$idx.':anonymous'}) {
                      $anonflag = 'anon';
                  }
                  $anonscript = (<<END);
  function setposttype () {
      var currtype = "$anonflag";
      for (var i=0; i<document.mailform.discuss.length; i++) {
	  if (document.mailform.elements.discuss[i].value == currtype ) {
	      document.mailform.elements.discuss[i].checked=1;
	  } 
      }
      return
  }
END
              }
          }
      }
      if ($env{'form.previous'}) {
          $prevtag = '<input type="hidden" name="previous" value="'.$env{'form.previous'}.'" />';
      }
  }

  if ($env{'form.origpage'}) {
      $subject = &unescape($env{'form.subject'});
      $comment = &unescape($env{'form.comment'});
      &process_attachments(\@currnewattach,\@currdelold,\@keepold);
  }
  my $latexHelp=&Apache::loncommon::helpLatexCheatsheet(undef,undef,1,($env{'form.modal'}?'popup':0));
  my $send=&mt('Send');
  my $alert = &mt('Please select a feedback type.');
  &js_escape(\$alert);
  my $js= <<END;
<script type="text/javascript">
//<!--
    function gosubmit() {
        var rec=0;
        if (typeof(document.mailform.elements.discuss)!="undefined") {
	    if (typeof(document.mailform.elements.discuss.length) == "undefined") {
		if (document.mailform.elements.discuss.checked ) {
		    rec=1;
		}
	    } else {
		for (var i=0; i<document.mailform.elements.discuss.length; i++) {
		    if (document.mailform.elements.discuss[i].checked ) {
			rec=1;
		    } 
		}
	    }
	}
        if (typeof(document.mailform.elements.blog)!="undefined") {
          if (document.mailform.elements.blog.checked) {
             rec=1;
          } 
        }

        if (rec) {
            if (typeof(document.mailform.onsubmit)=='function') {
		document.mailform.onsubmit();
	    }
	    document.mailform.submit();
        } else {
            alert('$alert');
	}
    }
    $anonchk
    $anonscript
//-->
</script>
<script type="text/javascript" src="/res/adm/includes/file_upload.js"></script>
END

  my ($textareaheader,$textareaclass);
  if (&Apache::lonhtmlcommon::htmlareabrowser()) {
      $textareaheader = &Apache::lonhtmlcommon::htmlareaselectactive();
      $textareaclass = 'class="LC_richDefaultOff"';
      if ($env{'request.course.id'}) {
          unless (($env{'course.'.$env{'request.course.id'}.'.allow_limited_html_in_feedback'} =~ /^\s*yes\s*$/i) || ($env{'form.sendmessageonly'})) {
              undef($textareaclass);
          }
      }
  }

  # Breadcrumbs
  my $brcrum = [{'href' => '',
                 'text' => 'Resource Feedback and Discussion'}];

  my %onload = ('onload' => 'window.focus();setposttype();');
  my %parms=('add_entries' => \%onload);
  if ($env{'form.modal'} ne 'yes') { $parms{'bread_crumbs'} = $brcrum; }
  my $start_page=
      &Apache::loncommon::start_page('Resource Feedback and Discussion',$js,\%parms);

  if ($quote ne '') {
      $quote = &HTML::Entities::decode($quote);
      unless (&contains_block_html($quote)) {
          &newline_to_br(\$quote);
      }
        $quote=&Apache::lonhtmlcommon::start_pick_box().
               &Apache::lonhtmlcommon::row_title(&mt('Quote')).
               &Apache::lontexconvert::msgtexconverted($quote).
               &Apache::lonhtmlcommon::row_closure(1).
               &Apache::lonhtmlcommon::end_pick_box();
  }
  my $header='';
  unless ($env{'form.modal'}) {
     $header="<h2><tt>$restitle</tt></h2>";
  }
  $r->print(<<END);
$start_page
<h1>$lt{'myqu'}</h1>
$header
<form action="/adm/feedback" method="post" name="mailform"
enctype="multipart/form-data">
$prevtag
<input type="hidden" name="postdata" value="$feedurl" />
<input type="hidden" name="modal" value="$env{'form.modal'}" />
END
  if ($env{'form.replydisc'}) {
      $r->print(<<END);
<input type="hidden" name="replydisc" value="$env{'form.replydisc'}" />
END
  } elsif ($env{'form.editdisc'}) {
     $r->print(<<END);
<input type="hidden" name="editdisc" value="$env{'form.editdisc'}" />
<input type="hidden" name="parentmsg" value="$parentmsg" />
END
  }
  $r->print(<<END);
$options
<br />
END
$r->print(&Apache::lonhtmlcommon::start_pick_box());
$r->print(<<END);
$quote
<p>
$textareaheader
</p>
<p>
$latexHelp
</p>
<p>
END

    
    $r->print(&Apache::lonhtmlcommon::row_title(&mt('Subject')));
    $r->print('<input type="text" name="subject" size="30" value="'.
              $subject.'" /></p>');
    $r->print(&Apache::lonhtmlcommon::row_closure());
    $r->print(&Apache::lonhtmlcommon::row_title(&mt('Message')));
    $r->print('<textarea name="comment" id="comment" cols="55" rows="10" '.
              $textareaclass.'>'.$comment.
              '</textarea>');
    $r->print(&Apache::lonhtmlcommon::row_closure(1));
    $r->print(&Apache::lonhtmlcommon::end_pick_box());

    if ( ($env{'form.editdisc'}) || ($env{'form.replydisc'}) ) {
        if ($env{'form.origpage'}) {
            foreach my $attach (@currnewattach) {
                $r->print('<input type="hidden" name="currnewattach" value="'.$attach.'" />'."\n");
            }
            foreach my $oldatt (@currdelold) {
                $r->print('<input type="hidden" name="deloldattach" value="'.$oldatt.'" />'."\n");
            }
        }
        if ($env{'form.editdisc'}) {
            if ($attachmenturls) {
                &extract_attachments($attachmenturls,$idx,$numoldver,\$attachmsg,\%attachments,\%currattach,\@currdelold);
                $attachnum = scalar(keys(%currattach));
                foreach my $key (keys(%currattach)) {
                    $r->print('<input type="hidden" name="keepold" value="'.$key.'" />'."\n");
                }
            }
        }
    } else {
        $r->print(<<END);
<p>
$lt{'atta'} $attachmaxtext: <input type="file" name="attachment" class="LC_flUpload" />
<input type="hidden" id="LC_free_space" value="131072" />
</p>
END
    }
    if (exists($env{'form.group'})) {
        $r->print('<input type="hidden" name="group" value="'.$env{'form.group'}.'" />');
    }
    if (exists($env{'form.ref'})) {
        $r->print('<input type="hidden" name="ref" value="'.$env{'form.ref'}.'" />');
    }
    $r->print(<<END);
<input type="hidden" name="sendit" value="1" />
<input type="button" value="$send" onclick='gosubmit();' />
</form>
END
    if ($env{'form.editdisc'} || $env{'form.replydisc'}) {
        my $now = time;
        my $ressymb = $symb;
        &Apache::lonenc::check_encrypt(\$ressymb);
        my $postidx = '';
        if ($env{'form.editdisc'}) {
            $postidx = $idx;
        }
        if (@currnewattach > 0) {
            $attachnum += @currnewattach;
        }
        my $blockblog = &Apache::loncommon::blocking_status('blogs');
        if ($attachnum > 0) {
            if (@currnewattach > 0) {
                $newattachmsg .= '<br /><b>'.&mt('New attachments').'</b><br />';
                if (@currnewattach > 1) {
                    $newattachmsg .= '<ol>';
                    foreach my $item (@currnewattach) {
                        $item =~ m#.*/([^/]+)$#;
                        $newattachmsg .= '<li><a href="'.$item.'">'.$1.'</a></li>'."\n";
                    }
                    $newattachmsg .= '</ol>'."\n";
                } else {
                    $currnewattach[0] =~ m#.*/([^/]+)$#;
                    $newattachmsg .= '<a href="'.$currnewattach[0].'">'.$1.'</a><br />'."\n";
                }
            }
            if ($attachmsg) {
                $r->print("<br /><b>$lt{'reta'}</b>:$attachmsg<br />\n");
            }
            if ($newattachmsg) {
                $r->print("$newattachmsg");
            }
        }
        $r->print(&generate_attachments_button($postidx,$attachnum,$ressymb,$now,\@currnewattach,\@currdelold,$numoldver,'',$blockblog));
    }
    $r->print(&generate_preview_button().
	      &Apache::loncommon::end_page());

}

sub print_display_options {
    my ($r,$symb,$previous,$dispchgA,$dispchgB,$markchg,$toggchg,$feedurl) = @_;
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;

    my $function = &Apache::loncommon::get_users_function();
    my $tabcolor = &Apache::loncommon::designparm($function.'.tabbg',
                                                    $env{'user.domain'});

    my %lt = &Apache::lonlocal::texthash(
        'pref' => 'Display Preference',
        'curr' => 'Current setting ',
        'actn' => 'Action',
        'deff' => 'Default for all discussions',
        'prca' => 'Preferences can be set for this discussion that determine ....',
        'whpo' => 'Which posts are displayed when you display this discussion board or resource, and',
        'unwh' => 'Under what circumstances posts are identified as "NEW", and',
        'wipa' => 'Whether individual posts can be marked as read/unread',
        'allposts' => 'All posts',
        'unread' => 'New posts only',
        'unmark' => 'Posts not marked read',
        'ondisp' => 'Once displayed',
        'onmark' => 'Once marked not NEW',
        'toggon' => 'Shown',
        'toggoff' => 'Not shown',
        'disa' => 'Posts displayed?',
        'npmr' => 'New posts cease to be identified as "NEW"?',
        'dotm' => 'Option to mark each post as read/unread?',  
        'chgt' => 'Change to ',
        'mkdf' => 'Set to ',
        'yhni' => 'You have not indicated that you wish to change any of the discussion settings',
        'ywbr' => 'You will be returned to the previous page if you click OK.'
    );
    my %js_lt = &Apache::lonlocal::texthash(
        'yhni' => 'You have not indicated that you wish to change any of the discussion settings',
        'ywbr' => 'You will be returned to the previous page if you click OK.'
    );
    &js_escape(\%js_lt);

    my $dispchangeA = $lt{'unread'};
    my $dispchangeB = $lt{'unmark'};
    my $markchange = $lt{'ondisp'};
    my $toggchange = $lt{'toggon'};
    my $currdisp = $lt{'allposts'};
    my $currmark = $lt{'onmark'};
    my $discdisp = 'allposts';
    my $discmark = 'onmark';
    my $currtogg = $lt{'toggoff'};
    my $disctogg = 'toggoff';
                                                                                      
    if ($dispchgA eq 'allposts') {
        $dispchangeA = $lt{'allposts'};
        $currdisp = $lt{'unread'};
        $discdisp = 'unread';
    }

    if ($markchg eq 'markonread') {
        $markchange = $lt{'onmark'};
        $currmark = $lt{'ondisp'};
        $discmark = 'ondisp';
    }

    if ($dispchgB eq 'onlyunread') {
        $dispchangeB = $lt{'unread'};
        $currdisp = $lt{'unmark'};
        $discdisp = 'unmark';
    }
    if ($toggchg eq 'toggoff') {
        $toggchange = $lt{'toggoff'};
        $currtogg = $lt{'toggon'};
        $disctogg = 'toggon';
    }

    my $js = <<END;
<script type="text/javascript">
function discdispChk(caller) {
    var disctogg = '$toggchg'
    if (caller == 0) {
        if (document.modifydisp.discdisp[0].checked == true) {
            if (document.modifydisp.discdisp[1].checked == true) {
                document.modifydisp.discdisp[1].checked = false
            }
        }
    }
    if (caller == 1) {
        if (document.modifydisp.discdisp[1].checked == true) {
            if (document.modifydisp.discdisp[0].checked == true) {
                document.modifydisp.discdisp[0].checked = false
            }
            if (disctogg == 'toggon') {
                document.modifydisp.disctogg.checked = true
            }
            if (disctogg == 'toggoff') {
                document.modifydisp.disctogg.checked = false
            }
        }
    }
    if (caller == 2) {
        var dispchgB = '$dispchgB'
        if (disctogg == 'toggoff') {
            if (document.modifydisp.disctogg.checked == true) {
                if (dispchgB == 'onlyunmark') {
                    document.modifydisp.discdisp[1].checked = false
                }
            }
        }
    }  
}

function setDisp() {
    var prev = "$previous"
    var chktotal = 0
    if (document.modifydisp.discdisp[0].checked == true) {
        document.modifydisp.$dispchgA.value = "$symb"
        chktotal ++
    }
    if (document.modifydisp.discdisp[1].checked == true) {
        document.modifydisp.$dispchgB.value = "$symb"
        chktotal ++
    }
    if (document.modifydisp.discmark.checked == true) {
        document.modifydisp.$markchg.value = "$symb"
        chktotal ++
    }
    if (document.modifydisp.disctogg.checked == true) {
        document.modifydisp.$toggchg.value = "$symb"
        chktotal ++
    }
    if (chktotal > 0) { 
        document.modifydisp.submit()
    } else {
        if(confirm("$js_lt{'yhni'}. \\n$js_lt{'ywbr'}"))      {
            if (prev > 0) {
                location.href = "$feedurl?previous=$previous"
            } else {
                location.href = "$feedurl"
            }
        }
    }
}
</script>
END


    my $start_page =
	&Apache::loncommon::start_page('Discussion display options',$js);
    my $end_page =
	&Apache::loncommon::end_page();
    $r->print(<<END);
$start_page
<form name="modifydisp" method="post" action="/adm/feedback">
$lt{'sdpf'}<br/> $lt{'prca'}  <ol><li>$lt{'whpo'}</li><li>$lt{'unwh'}</li><li>$lt{'wipa'}</li></ol>
<br />
END
    $r->print(&Apache::loncommon::start_data_table());
    $r->print(<<END);
       <tr>
        <th>$lt{'pref'}</td>
        <th>$lt{'curr'}</td>
        <th>$lt{'actn'}?</td>
       </tr>
END
    $r->print(&Apache::loncommon::start_data_table_row());
    $r->print(<<END);
       <td>$lt{'disa'}</td>
       <td>$lt{$discdisp}</td>
       <td><label><input type="checkbox" name="discdisp" onclick="discdispChk('0')" />&nbsp;$lt{'chgt'} "$dispchangeA"</label>
           <br />
           <label><input type="checkbox" name="discdisp" onclick="discdispChk('1')" />&nbsp;$lt{'chgt'} "$dispchangeB"</label>
       </td>
END
    $r->print(&Apache::loncommon::end_data_table_row());
    $r->print(&Apache::loncommon::start_data_table_row());
    $r->print(<<END);
       <td>$lt{'npmr'}</td>
       <td>$lt{$discmark}</td>
       <td><label><input type="checkbox" name="discmark" />$lt{'chgt'} "$markchange"</label></td>
END
    $r->print(&Apache::loncommon::end_data_table_row());
    $r->print(&Apache::loncommon::start_data_table_row());
    $r->print(<<END);
       <td>$lt{'dotm'}</td>
       <td>$lt{$disctogg}</td>
       <td><label><input type="checkbox" name="disctogg" onclick="discdispChk('2')" />$lt{'chgt'} "$toggchange"</label></td>
END
    my $save = &mt('Save');
    $r->print(&Apache::loncommon::end_data_table_row());
    $r->print(&Apache::loncommon::end_data_table());
    $r->print(<<END);
<br />
<br />
<input type="hidden" name="symb" value="$symb" />
<input type="hidden" name="previous" value="$previous" />
<input type="hidden" name="$dispchgA" value="" />
<input type="hidden" name="$dispchgB" value="" />
<input type="hidden" name="$markchg" value="" />
<input type="hidden" name="$toggchg" value="" />
<input type="button" name="sub" value="$save" onclick="javascript:setDisp()" />
END
    if (exists($env{'form.group'})) {
        $r->print('<input type="hidden" name="group" value="'.$env{'form.group'}.'" />');
    }
    if (exists($env{'form.ref'})) {
        $r->print('<input type="hidden" name="ref" value="'.$env{'form.ref'}.'" />');
    }
    $r->print("
<br />
<br />
</form>
$end_page
    ");
    return;
}

sub print_sortfilter_options {
    my ($r,$symb,$previous,$feedurl) = @_;

    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;

    &Apache::lonenc::check_encrypt(\$symb);
    my @sections;
    my $section_sel = '';
    my $numvisible = 5;
    my @groups;
    my $group_sel = '';
    my $numgroupvis = 5;
    my %sectioncount = &Apache::loncommon::get_sections();
    my @courseroles = qw(st ad ep ta in);
    my $crstype = &Apache::loncommon::course_type();
    my $ccrole = 'cc';
    if ($crstype eq 'Community') {
        $ccrole = 'co';
    }
    push(@courseroles,$ccrole);
    
    if ($env{'request.course.sec'} !~ /^\s*$/) {  #Restrict section choice to current section 
        @sections = ('all',$env{'request.course.sec'});
        $numvisible = 2;
    } else {
        @sections = sort {$a cmp $b} keys(%sectioncount);
        if (scalar(@sections) < 4) {
            $numvisible = scalar(@sections) + 1;
        }
        unshift(@sections,'all'); # Put 'all' at the front of the list

    }
    foreach my $sec (@sections) {
        $section_sel .= "  <option value=\"$sec\">$sec</option>\n";
    }

    if (&check_group_priv() eq 'ok') {
        my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
        my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'}; 
        my %curr_groups = &Apache::longroup::coursegroups($cdom,$cnum);
        @groups = sort {$a cmp $b} keys(%curr_groups);
        if (scalar(@groups) < 4) {
            $numgroupvis = scalar(@groups) + 1;
        }
        unshift(@groups,'all'); # Put 'all' at the front of the list
    } else { 
        my @coursegroups = split(/:/,$env{'request.course.groups'});
        if (@coursegroups > 0) {
            @coursegroups = sort {$a cmp $b} @coursegroups;
            @groups = ('all',@coursegroups);
            if (scalar(@groups) < 4) {
                $numgroupvis = scalar(@groups) + 1;
            }
        } else {
            @groups = ('all');
            $numgroupvis = 1;
        }
    }
    foreach my $group (@groups) {
        $group_sel .= "  <option value=\"$group\">$group</option>\n";
    }

    my $function = &Apache::loncommon::get_users_function();
    my $tabcolor = &Apache::loncommon::designparm($function.'.tabbg',
                                                    $env{'user.domain'});
    my %lt = &Apache::lonlocal::texthash(
        'diop' => 'Display Options',
        'curr' => 'Current setting ',
        'actn' => 'Action',
        'prca' => 'Set options that control the sort order of posts, and/or which posts are displayed.',
        'soor' => 'Sort order',
        'spur' => 'Specific user roles',
        'sprs' => 'Specific role status',
        'spse' => 'Specific sections',
        'spgr' => 'Specific groups',
        'psub' => 'Pick specific users (by name)',
        'shal' => 'Show a list of current posters',
        'stor' => 'Save changes',
    );

    my %sort_types = ();
    my %role_types = ();
    my %status_types = ();
    &sort_filter_names(\%sort_types,\%role_types,\%status_types,$crstype);

    my $js = <<END;
<script type="text/javascript">
function verifyFilter() {
    var rolenum = 0
    for (var i=0; i<document.modifyshown.rolefilter.length; i++) {
        if (document.modifyshown.rolefilter.options[i].selected == true) {
            rolenum ++
        }
    }
    if (rolenum == 0) {
        document.modifyshown.rolefilter.options[0].selected = true
    }

    var secnum = 0
    for (var i=0; i<document.modifyshown.sectionpick.length; i++) {
        if (document.modifyshown.sectionpick.options[i].selected == true) {
            secnum ++
        }
    }
    if (secnum == 0) {
        document.modifyshown.sectionpick.options[0].selected = true
    }

    var grpnum = 0
    for (var i=0; i<document.modifyshown.grouppick.length; i++) {
        if (document.modifyshown.grouppick.options[i].selected == true) {
            grpnum ++
        }
    }
    if (grpnum == 0) {
        document.modifyshown.grouppick.options[0].selected = true
    }

    document.modifyshown.submit();
}
</script>
END

    my $start_page=
	&Apache::loncommon::start_page('Discussion options',$js);
    my $end_page=
	&Apache::loncommon::end_page();

    $r->print(<<END);
$start_page
<form name="modifyshown" method="post" action="/adm/feedback">
<b>$lt{'diso'}</b><br/> $lt{'prca'}
<br />
<table border="0">
 <tr>
  <th>$lt{'soor'}</th>
  <th>&nbsp;</th>
  <th>$lt{'sprs'}</th>
  <th>&nbsp;</th>
  <th>$lt{'spur'}</th>
  <th>&nbsp;</th>
  <th>$lt{'spse'}</th>
  <th>&nbsp;</th>
  <th>$lt{'spgr'}</th>
  <th>&nbsp;</th>
  <th>$lt{'psub'}</th>
 </tr>
 <tr>
  <td align="center" valign="top">
   <select name="sortposts">
    <option value="ascdate" selected="selected">$sort_types{'ascdate'}</option>
    <option value="descdate">$sort_types{'descdate'}</option>
    <option value="thread">$sort_types{'thread'}</option>
    <option value="subject">$sort_types{'subject'}</option>
    <option value="username">$sort_types{'username'}</option>
    <option value="lastfirst">$sort_types{'lastfirst'}</option>
   </select>
  </td>
  <td>&nbsp;</td>
  <td align="center" valign="top">
   <select name="statusfilter">
    <option value="all" selected="selected">$status_types{'all'}</option>
    <option value="Active">$status_types{'Active'}</option>
    <option value="Expired">$status_types{'Expired'}</option>
    <option value="Future">$status_types{'Future'}</option>
   </select>
  </td>
  <td>&nbsp;</td>
  <td align="center" valign="top">
   <select name="rolefilter" multiple="multiple" size="5">
    <option value="all">$role_types{'all'}</option>
    <option value="st">$role_types{'st'}</option>
    <option value="$ccrole">$role_types{$ccrole}</option>
    <option value="in">$role_types{'in'}</option>
    <option value="ta">$role_types{'ta'}</option>
    <option value="ep">$role_types{'ep'}</option>
    <option value="ad">$role_types{'ad'}</option>
    <option value="cr">$role_types{'cr'}</option>
   </select>
  </td>
  <td>&nbsp;</td>
  <td align="center" valign="top">
   <select name="sectionpick" multiple="multiple" size="$numvisible">
    $section_sel
   </select>
  </td>
  <td>&nbsp;</td>
  <td align="center" valign="top">
   <select name="grouppick" multiple="multiple" size="$numvisible">
    $group_sel
   </select>
  </td>
  <td>&nbsp;</td>
  <td valign="top"><label><input type="checkbox" name="posterlist" value="$symb" />$lt{'shal'}</label></td>
 </tr>
</table>
<br />
<input type="hidden" name="inhibitmenu" value="$env{'form.inhibitmenu'}" />
<input type="hidden" name="modal" value="$env{'form.modal'}" />
<input type="hidden" name="previous" value="$previous" />
<input type="hidden" name="applysort" value="$symb" />
<input type="button" name="sub" value="$lt{'stor'}" onclick="verifyFilter()" />
END
    if (exists($env{'form.group'})) {
        $r->print('<input type="hidden" name="group" value="'.$env{'form.group'}.'" />');
    }
    if (exists($env{'form.ref'})) {
        $r->print('<input type="hidden" name="ref" value="'.$env{'form.ref'}.'" />');
    }
    $r->print("
<br />
<br />
</form>
$end_page
");
}

sub print_showposters {
    my ($r,$symb,$previous,$feedurl,$sortposts) = @_;

    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;

    &Apache::lonenc::check_encrypt(\$symb);
    my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
    my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
    my $group = $env{'form.group'};
    my $ressymb = &wrap_symb($symb);
    my $seehidden = &can_see_hidden('',$ressymb,$feedurl,$group,$cdom,$cnum);
    my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
                                         $cdom,$cnum);
    my %namesort = ();
    my %postcounts = ();

    my %lt = &Apache::lonlocal::texthash(
                                          sele => 'Select',
                                          full => 'Fullname',
                                          usdo => 'Username:domain',
                                          post => 'Posts',
                                        );
    if ($contrib{'version'}) {
        for (my $idx=1;$idx<=$contrib{'version'};$idx++) {
            my $hidden=($contrib{'hidden'}=~/\.$idx\./);
            my $deleted=($contrib{'deleted'}=~/\.$idx\./);
            unless ((($hidden) && (!$seehidden)) || ($deleted)) {
                if ((!$contrib{$idx.':anonymous'}) || (&Apache::lonnet::allowed('rin',$env{'request.course.id'}.($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:'')))) {
                    my %names = &Apache::lonnet::get('environment',['firstname','lastname'],$contrib{$idx.':senderdomain'},$contrib{$idx.':sendername'});
                    my $lastname = $names{'lastname'};
                    my $firstname = $names{'firstname'};
                    if ($lastname eq '') {
                        $lastname = '_';
                    }
                    if ($firstname eq '') {
                        $firstname = '_';
                    }
                    unless (defined($namesort{$lastname})) {
                        %{$namesort{$lastname}} = ();
                    }
                    my $poster =  $contrib{$idx.':sendername'}.':'.$contrib{$idx.':senderdomain'};
                    $postcounts{$poster} ++;
                    if (defined($namesort{$lastname}{$firstname})) {
                        if (!grep/^$poster$/,@{$namesort{$lastname}{$firstname}}) {
                            push(@{$namesort{$lastname}{$firstname}}, $poster);
                        }
                    } else {
                        @{$namesort{$lastname}{$firstname}} = ("$poster");
                    }
                }
            }
        }       
    }

    my $start_page = &Apache::loncommon::start_page('Discussion options');
    my $table_start =&Apache::loncommon::start_data_table();
    $r->print(<<END);
$start_page
 <form name="pickpostersform" method="post" action="">
 <br />
    $table_start
      <tr>
       <th>#</th>
       <th>$lt{'sele'}</th>
       <th>$lt{'full'} <font color="#999999">($lt{'usdo'})</font></th>
       <th>$lt{'post'}</th>
      </tr>
END
    my $count = 0;
    foreach my $last (sort(keys(%namesort))) {
        foreach my $first (sort(keys(%{$namesort{$last}}))) {
            foreach my $user (sort(@{$namesort{$last}{$first}})) {
                my ($uname,$udom) = split(/:/,$user);
                if (!$uname || !$udom) { 
                    next;
                } else {
                    $count ++;
                    $r->print(&Apache::loncommon::start_data_table_row().
			      '<td align="right">'.$count.'</td>
                               <td align="center"><label><input name="stuinfo" type="checkbox" value="'.$user.'" /></td>
                               <td>'.$last.', '.$first.' ('.$uname.':'.$udom.')</label></td>
                               <td>'.$postcounts{$user}.'</td>'.
			      &Apache::loncommon::end_data_table_row());
                }
            }
        }
    }
    $r->print(&Apache::loncommon::end_data_table());
    my $end_page   = &Apache::loncommon::end_page();
    $r->print(<<END);
<br />
<input type="hidden" name="sortposts" value="$sortposts" />
<input type="hidden" name="modal" value="$env{'form.modal'}" />
<input type="hidden" name="userpick" value="$symb" />
<input type="button" name="store" value="Display posts" onclick="javascript:document.pickpostersform.submit()" />
</form>
$end_page
END
}

sub get_post_versions {
    my ($versions,$incoming,$htmldecode,$numver) = @_;
    if ($incoming =~ /^<version num="0">/) {
        my $p = HTML::LCParser->new(\$incoming);
        my $done = 0; 

        while ( (my $token = $p->get_tag("version")) && (!$done)) {
            my $num = $token->[1]{num};
            my $text = $p->get_text("/version");
            if (defined($numver)) {
                if ($num == $numver) {
                    if ($htmldecode) {
                        $text = &HTML::Entities::decode($text);
                    }
                    $$versions{$numver}=$text;
                    $done = 1;
                }
            } else {
                if ($htmldecode) {
                    $text = &HTML::Entities::decode($text);
                }
                $$versions{$num}=$text;
            }
        }
    } else {
        if (!defined($numver)) {
            $numver = 0;
        }
        if ($htmldecode) {
            $$versions{$numver} = $incoming;
        } else {
            $$versions{$numver} = &HTML::Entities::encode($incoming,'<>&"');
        }
    }
    return;
}

sub get_post_attachments {
    my ($attachments,$attachmenturls) = @_;
    my $num;
    if ($attachmenturls =~ m/^<attachment id="0">/) {
        my $p = HTML::LCParser->new(\$attachmenturls);
        while (my $token = $p->get_tag("attachment","filename","post"))  {
            if ($token->[0] eq "attachment") {
                $num = $token->[1]{id};
                %{$$attachments{$num}} =();
            } elsif ($token->[0] eq "filename") {
                $$attachments{$num}{'filename'} = $p->get_text("/filename");
            } elsif ($token->[0] eq "post") {
                my $id = $token->[1]{id};
                $$attachments{$num}{$id} = $p->get_text("/post");
            }
        }
    } else {
        %{$$attachments{'0'}} = ();
        $$attachments{'0'}{'filename'} = $attachmenturls;
        $$attachments{'0'}{'0'} = 'n';
    }

    return;
}

sub fail_redirect {
  my ($r,$feedurl) = @_;
  if ($feedurl=~/^\/adm\//) { $feedurl.='?register=1' };
  my %lt = &Apache::lonlocal::texthash(
                 'sorr' => 'Sorry, no recipients ...',
  );
  my $logo=&Apache::loncommon::lonhttpdurl('/adm/lonIcons/lonlogos.gif');
  $r->print(&Apache::loncommon::start_page('Feedback not sent',undef,
					   {'redirect'  => [2,$feedurl],
					    'only_body' => 1,}));
  $r->print(<<ENDFAILREDIR);
<img align="right" src="$logo" />
<p class="LC_warning">$lt{'sorr'}</p>
ENDFAILREDIR
  $r->print(&Apache::loncommon::end_page());
}

sub redirect_back {
  my ($r,$feedurl,$typestyle,$sendsomething,$sendposts,$blog,$status,$previous,$sort,$rolefilter,$statusfilter,$sectionpick,$grouppick,$numpicks,$group,$toolarge) = @_;
  my $sorttag = '';
  my $roletag = '';
  my $statustag = '';
  my $sectag = '';
  my $grptag = '';
  my $userpicktag = '';
  my $qrystr = '';
  my $prevtag = '';

  &Apache::loncommon::content_type($r,'text/html');
  $r->send_http_header;
  &dewrapper(\$feedurl);
  if ($feedurl=~/^\/adm\//) { $feedurl.='?register=1' };
  if ($previous > 0) {
      $qrystr = 'previous='.$previous;
      if ($feedurl =~ /\?register=1/) {
          $feedurl .= '&amp;'.$qrystr;
      } else {
          $feedurl .= '?'.$qrystr;
      }
      $prevtag = '<input type="hidden" name="previous" value="'.$previous.'" />';
  }
  if (defined($sort)) {
      my $sortqry = 'sortposts='.$sort;
      if (($feedurl =~ /\?register=1/) || ($feedurl =~ /\?previous=/)) {
          $feedurl .= '&amp;'.$sortqry;
      } else {
          $feedurl .= '?'.$sortqry;
      }
      $sorttag = '<input type="hidden" name="sortposts" value="'.$sort.'" />';
      if (defined($numpicks)) {
          my $userpickqry = 'totposters='.$numpicks;
          $feedurl .= '&amp;'.$userpickqry;
          $userpicktag = '<input type="hidden" name="totposters" value="'.$numpicks.'" />';
      } else {
          if (ref($sectionpick) eq 'ARRAY') {
              $feedurl .= '&amp;sectionpick=';
              $sectag .=  '<input type="hidden" name="sectionpick" value="';
              foreach my $sec (@{$sectionpick}) {
                  $feedurl .= $sec.',';
                  $sectag .= $sec.',';
              }
              $feedurl =~ s/,$//;
              $sectag =~ s/,$//;
              $sectag .= '" />';
          } else {
              $feedurl .= '&amp;sectionpick='.$sectionpick;
              $sectag = '<input type="hidden" name="sectionpick" value="'.$sectionpick.'" />';
          }
          if (ref($grouppick) eq 'ARRAY') {
              $feedurl .= '&amp;grouppick=';
              $sectag .=  '<input type="hidden" name="grouppick" value="';
              foreach my $grp (@{$grouppick}) {
                  $feedurl .= $grp.',';
                  $grptag .= $grp.',';
              }
              $feedurl =~ s/,$//;
              $grptag =~ s/,$//;
              $grptag .= '" />';
          } else {
              $feedurl .= '&amp;grouppick='.$grouppick;
              $grptag = '<input type="hidden" name="grouppick" value="'.$grouppick.'" />';
          }
          if (ref($rolefilter) eq 'ARRAY') {
              $feedurl .= '&amp;rolefilter=';
              $roletag .=  '<input type="hidden" name="rolefilter" value="';
              foreach my $role (@{$rolefilter}) {
                  $feedurl .= $role.',';
                  $roletag .= $role.',';
              }
              $feedurl =~ s/,$//;
              $roletag =~ s/,$//;
              $roletag .= '" />';
          } else {
              $feedurl .= '&amp;rolefilter='.$rolefilter;
              $roletag = '<input type="hidden" name="rolefilter" value="'.$rolefilter.'" />';
          }
          $feedurl .= '&amp;statusfilter='.$statusfilter;
          $statustag ='<input type="hidden" name="statusfilter" value="'.$statusfilter.'" />';
      }
  }
  my $grouptag;
  if ($group ne '') {
      $grouptag = '<input type="hidden" name="group" value="'.$group.'" />';
      my $refarg;
      if (exists($env{'form.ref'})) {
          $refarg = '&amp;ref='.$env{'form.ref'};
          $grouptag .= '<input type="hidden" name="ref" value="'.$env{'form.ref'}.'" />';
      }
      if ($feedurl =~ /\?/) {
          $feedurl .= '&amp;group='.$group.$refarg;
      } else {
          $feedurl .= '?group='.$group.$refarg;
      }
  } 
  &Apache::lonenc::check_encrypt(\$feedurl);
  my $logo=&Apache::loncommon::lonhttpdurl('/adm/lonIcons/lonlogos.gif');
  my %parms=('only_body'   => 1);
  if ($env{'form.modal'}) {
      $parms{'add_entries'}={'onLoad' => 'document.forms.reldt.submit()'};
  } else {
      $parms{'redirect'}=[0,$feedurl];
  }
  my $start_page=
      &Apache::loncommon::start_page('Feedback sent',undef,\%parms);
  my $end_page = &Apache::loncommon::end_page();
  $r->print(<<ENDREDIR);
$start_page
<img align="right" src="$logo" />
$typestyle
<b>Sent $sendsomething message(s), and $sendposts post(s).</b>
$blog
$toolarge
<font color="red">$status</font>
<form name="reldt" action="$feedurl" target="loncapaclient">
$prevtag
$sorttag
$statustag
$roletag
$sectag
$grptag
$userpicktag
$grouptag
</form>
$end_page
ENDREDIR
}

sub no_redirect_back {
  my ($r,$feedurl) = @_;
  my $nofeed=&mt('Sorry, no feedback possible on this resource ...');
 
  my %onload;

  my %body_options = ('only_body'   => 1,
		      'bgcolor'     => '#FFFFFF',
		      'add_entries' => \%onload,);

  if ($feedurl !~ m{^/adm/feedback}) { 
      $body_options{'redirect'} = [2,$feedurl];
  }
  my $start_page=
      &Apache::loncommon::start_page('Feedback not sent',undef,
				     \%body_options);
				      
  my $end_page = &Apache::loncommon::end_page();

  &Apache::lonenc::check_encrypt(\$feedurl);
  my $logo=&Apache::loncommon::lonhttpdurl('/adm/lonIcons/lonlogos.gif');
  $r->print (<<ENDNOREDIRTWO);
$start_page
<img align="right" src="$logo" />
<b>$nofeed</b>
<br />
$end_page
ENDNOREDIRTWO
}

sub screen_header {
    my ($feedurl,$symb,$group) = @_;
    my $crscontent = &mt('Question/Comment/Feedback about course content');
    my $crspolicy = &mt('Question/Comment/Feedback about course policy');
    my $contribdisc = &mt('Contribution to course discussion of resource');
    my $anoncontrib = &mt('Anonymous contribution to course discussion of resource');
    my $namevis = &mt('name only visible to course faculty');
    my $crstype;
    if ($env{'request.course.id'}) {
        $crstype = &Apache::loncommon::course_type();
        if ($crstype eq 'Community') {
            $crscontent = &mt('Question/Comment/Feedback about community content');
            $crspolicy = &mt('Question/Comment/Feedback about community policy');
            $contribdisc = &mt('Contribution to community discussion of resource');
            $anoncontrib = &mt('Anonymous contribution to community discussion of resource');
            $namevis = &mt('name only visible to community facilitators');
        }
    }
    my $msgoptions='';
    my $discussoptions='';
    unless (($env{'form.replydisc'}) || ($env{'form.editdisc'})) {
	if (($feedurl=~/^\/res\//) && ($feedurl!~/^\/res\/adm/) && ($env{'user.adv'})) {
	    $msgoptions= 
		'<label><input type="radio" name="discuss" value="author" /> '.
		&mt('Feedback to resource author').'</label><br />';
	}
        my %optionhash=();
        foreach my $type ('question','comment','policy') {
	    $optionhash{$type}=$env{'course.'.$env{'request.course.id'}.'.'.$type.'.email.text'};
	}
	if (&feedback_available(1)) {
	    $msgoptions.=
		'<label><input type="radio" name="discuss" value="question" /> '.
		($optionhash{'question'}?$optionhash{'question'}:&mt('Question about resource content')).'</label><br />';
	}
	if (&feedback_available(0,1)) {
	    $msgoptions.=
		'<label><input type="radio" name="discuss" value="course" /> '.
		($optionhash{'comment'}?$optionhash{'comment'}:$crscontent).
		'</label><br />';
	}
	if (&feedback_available(0,0,1)) {
	    $msgoptions.=
		'<label><input type="radio" name="discuss" value="policy" /> '.
		($optionhash{'policy'}?$optionhash{'policy'}:$crspolicy).
		'</label><br />';
	}
    }
    if (($env{'request.course.id'}) && (!$env{'form.sendmessageonly'})) {
        my ($blocked,$blocktext) = &Apache::loncommon::blocking_status('boards');
        my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
        my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
        my $realsymb = &get_realsymb($symb);
        if (!$blocked && &discussion_open(undef,$realsymb) && 
	    (&Apache::lonnet::allowed('pch',
				      $env{'request.course.id'}.
				      ($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:'')) || 
            (($group ne '') && ($symb =~ m{^bulletin___\d+___adm/wrapper/adm/\Q$cdom\E/\Q$cnum\E/\d+/bulletinboard$}) && (&check_group_priv($group,'pgd') eq 'ok')))) {
	    $discussoptions='<label><input type="radio" name="discuss" value="nonanon" checked="checked" /> '.
		$contribdisc.
	        '</label><br /><label><input type="radio" name="discuss" value="anon" /> '.
		$anoncontrib.
		' <i>('.$namevis.')</i></label> '.
		'<a href="/adm/preferences?action=changescreenname">'.&mt('Change Screenname').'</a>';
            my $blockblog = &Apache::loncommon::blocking_status('blogs');
            if (!$blockblog) {
                $discussoptions.= &add_blog_checkbox($crstype);
            }
        }
    }
    if ($msgoptions) {
        $msgoptions='<tr><th><img src="'.&Apache::loncommon::lonhttpdurl('/res/adm/pages/feedback.png').'" />'
                   .'<br />'.&mt('Send Feedback').'<br />'.&Apache::lonhtmlcommon::coursepreflink(&mt('Feedback Settings'),'feedback').'</th>'.
                   '<td>'.$msgoptions.'</td></tr>';
    }
    if ($discussoptions) { 
	$discussoptions='<tr><th><img src="'.&Apache::loncommon::lonhttpdurl('/adm/lonMisc/chat.gif').'" alt="" />'
                        .'<br />'.&mt('Discussion Contributions').'<br />'.&Apache::lonhtmlcommon::coursepreflink(&mt('Discussion Settings'),'discussion').'</th>'.
                        '<td>'.$discussoptions.'</td></tr>';
    }
    return  &Apache::loncommon::start_data_table().$msgoptions.$discussoptions.&Apache::loncommon::end_data_table();
}

sub resource_output {
  my ($feedurl) = @_;
  my $usersaw=&Apache::lonnet::ssi_body($feedurl);
  $usersaw=~s/\<body[^\>]*\>//gi;
  $usersaw=~s/\<\/body\>//gi;
  $usersaw=~s/\<html\>//gi;
  $usersaw=~s/\<\/html\>//gi;
  $usersaw=~s/\<head\>//gi;
  $usersaw=~s/\<\/head\>//gi;
  $usersaw=~s/action\s*\=/would_be_action\=/gi;
  return $usersaw;
}

sub clear_out_html {
  my ($message,$override)=@_;
# Always allow the <m>-tag
  my %html=(M=>1);
# Check if more is allowed
  my $cid=$env{'request.course.id'};
  if (($env{"course.$cid.allow_limited_html_in_feedback"} =~ m/yes/i) ||
      ($override)) {
      # allows <B> <I> <P> <A> <LI> <OL> <UL> <EM> <BR> <TT> <STRONG> 
      # <BLOCKQUOTE> <DIV .*> <DIV> <IMG> <M> <SPAN> <H1> <H2> <H3> <H4> <SUB>
      # <SUP> <TABLE> <TR> <TD> <TH> <TBODY>
      %html=(B=>1, I=>1, P=>1, A=>1, LI=>1, OL=>1, UL=>1, EM=>1,
	     BR=>1, TT=>1, STRONG=>1, BLOCKQUOTE=>1, PRE=>1, DIV=>1, IMG=>1,
	     M=>1, CHEM=>1, ALGEBRA=>1, SUB=>1, SUP=>1, SPAN=>1,  
	     H1=>1, H2=>1, H3=>1, H4=>1, H5=>1, H6=>1, 
	     TABLE=>1, TR=>1, TD=>1, TH=>1, TBODY=>1);
  }
# Do the substitution of everything that is not explicitly allowed
  $message =~ s/\<(\/?\s*(\w+)[^\>\<]*)/
	  {($html{uc($2)}&&(length($1)<1000))?"\<$1":"\&lt;$1"}/ge;
  $message =~ s/(\<?\s*(\w+)[^\<\>]*)\>/
	  {($html{uc($2)}&&(length($1)<1000))?"$1\>":"$1\&gt;"}/ge;
  return $message;
}

sub assemble_email {
  my ($message,$prevattempts,$usersaw,$useranswer)=@_;
  my %lt = &Apache::lonlocal::texthash(
             'prev' => 'Previous attempts of student (if applicable)',
             'orig' => 'Original screen output (if applicable)',
             'corr' => 'Correct Answer(s) (if applicable)',
  );
  if (&Apache::loncommon::course_type() eq 'Community') {
      $lt{'prev'} = &mt('Previous attempts of member (if applicable)');
  }
  my $email=<<"ENDEMAIL";
$message
ENDEMAIL
    my $citations=<<"ENDCITE";
<h2>$lt{'prev'}</h2>
$prevattempts
<br /><hr />
<h2>$lt{'orig'}</h2>
$usersaw
<h2>$lt{'corr'}</h2>
$useranswer
ENDCITE
  return ($email,$citations);
}


sub feedback_available {
    my ($question,$course,$policy)=@_;
    my ($typestyle,%to)=&Apache::lonmsg::decide_receiver('',0,$question,
							 $course,$policy);
    return scalar(%to);
}

sub send_msg {
    my ($title,$feedurl,$email,$citations,$attachmenturl,$symb,%to)=@_;
    my $status='';
    my $sendsomething=0;
    my $restitle = &get_resource_title($symb,$feedurl);
    if ($title=~/^Error/) { $title=&mt('Feedback').': '.$title; }
    unless ($title=~/\w/) { $title=&mt('Feedback'); }
    foreach my $key (keys(%to)) {
	if ($key) {
	    my ($user,$domain) = split(/\:/,$key,2);
	    if (!defined($user)) {
		$status.='<br />'.&mt('Error sending message to [_1], no user specified.',$key);
	    } elsif (!defined($domain)) {
		$status.='<br />'.&mt('Error sending message to [_1], no domain specified.',$key);
	    } else {
		unless (&Apache::lonmsg::user_normal_msg($user,$domain,
							 $title.' ['.$restitle.']',$email,$citations,$feedurl,
							 $attachmenturl,undef,undef,$symb,$restitle)=~/ok/) {
		    $status.='<br />'.&mt('Error sending message to').' '.$key.'<br />';
		} else {
		    $sendsomething++;
		}
	    }
	}
    }

# Records of number of feedback messages are kept under the "symb" called "_feedback"
# There are two entries within the framework of a course:
# - the URLs for which feedback was provided
# - the total number of contributions
    if ($sendsomething) {
        my %record=&getfeedbackrecords();
        my ($temp)=keys(%record);
        unless ($temp=~/^error\:/) {
	    my %newrecord=();
	    $newrecord{'resource'}=$feedurl;
	    $newrecord{'subnumber'}=$record{'subnumber'}+1;
	    unless (&Apache::lonnet::cstore(\%newrecord,'_feedback') eq 'ok') {
	        $status.='<br />'.&mt('Not registered').'<br />';
	    }
        }
    }
    return ($status,$sendsomething);
}

# Routine to get the complete feedback records

sub getfeedbackrecords {
    my ($uname,$udom,$course)=@_;
    unless ($uname) { $uname=$env{'user.name'}; }
    unless ($udom)  { $udom=$env{'user.domain'}; }
    unless ($course) { $course=$env{'request.course.id'}; }
    my %record=&Apache::lonnet::restore('_feedback',$course,$udom,$uname);
    return %record;
}

# Routine to get feedback statistics

sub getfeedbackstats {
    my %record=&getfeedbackrecords(@_);
    return ($record{'subnumber'},$record{'points'},$record{'totallikes'});
}

# Store feedback credit

sub storefeedbackpoints {
    my ($points,$uname,$udom,$course)=@_;
    unless ($points) { $points=0; }
    unless ($uname) { $uname=$env{'user.name'}; }
    unless ($udom)  { $udom=$env{'user.domain'}; }
    unless ($course) { $course=$env{'request.course.id'}; }
    my %record=('grader_user'   => $env{'user.name'},
                'grader_domain' => $env{'user.domain'},
                'points' => $points);
    return &Apache::lonnet::cstore(\%record,'_feedback',$course,$udom,$uname);
}

# Store feedback "likes"

sub storefeedbacklikes {
    my ($likes,$uname,$udom,$course)=@_;
    unless ($likes) { $likes=0; }
    if ($likes>0) { $likes=1; }
    if ($likes<0) { $likes=-1; }
    unless ($uname) { $uname=$env{'user.name'}; }
    unless ($udom)  { $udom=$env{'user.domain'}; }
    unless ($course) { $course=$env{'request.course.id'}; }
    my %record=&getfeedbackrecords($uname,$udom,$course);
    my $totallikes=$record{'totallikes'};
    $totallikes+=$likes;
    my %newrecord=('likes_user'   => $env{'user.name'},
                   'likes_domain' => $env{'user.domain'},
                   'likes' => $likes,
                   'totallikes' => $totallikes);
    return &Apache::lonnet::cstore(\%newrecord,'_feedback',$course,$udom,$uname);
}


sub adddiscuss {
    my ($symb,$email,$anon,$attachmenturl,$subject,$group)=@_;
    my $status='';
    my $realsymb = &get_realsymb($symb);
    my ($cnum,$cdom);
    if ($env{'request.course.id'}) {
        $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
        $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
    }
    if (&discussion_open(undef,$realsymb) &&
	(&Apache::lonnet::allowed('pch',$env{'request.course.id'}.
         ($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:'')) || 
         (($group ne '') && (&check_group_priv($group,'pgd') eq 'ok') && 
         ($symb =~ m{^bulletin___\d+___adm/wrapper/adm/\Q$cdom\E/\Q$cnum\E/\d+/bulletinboard$})))) {

    my %contrib=('message'      => $email,
                 'sendername'   => $env{'user.name'},
                 'senderdomain' => $env{'user.domain'},
                 'screenname'   => $env{'environment.screenname'},
                 'plainname'    => $env{'environment.firstname'}.' '.
		                   $env{'environment.middlename'}.' '.
                                   $env{'environment.lastname'}.' '.
                                   $env{'enrironment.generation'},
                 'attachmenturl'=> $attachmenturl,
                 'subject'      => $subject);
    if ($env{'form.replydisc'}) {
	$contrib{'replyto'}=(split(/\:\:\:/,$env{'form.replydisc'}))[1];
    }
    if ($anon) {
	$contrib{'anonymous'}='true';
    }
    if (($symb) && ($email)) {
        my $now = time;
        if ($env{'form.editdisc'}) {
            $contrib{'ip'}=&Apache::lonnet::get_requestor_ip();
            $contrib{'host'}=$Apache::lonnet::perlvar{'lonHostID'};
            $contrib{'timestamp'} = $now;
            $contrib{'history'} = '';
            my $numoldver = 0;
            my ($oldsymb,$oldidx)=split(/\:\:\:/,$env{'form.editdisc'});
	    &Apache::lonenc::check_decrypt(\$oldsymb);
            $oldsymb=~s|(bulletin___\d+___)adm/wrapper/|$1|;
# get timestamp for last post and history
            my %oldcontrib=&Apache::lonnet::restore($oldsymb,$env{'request.course.id'},
                     $env{'course.'.$env{'request.course.id'}.'.domain'},
                     $env{'course.'.$env{'request.course.id'}.'.num'});
            if (defined($oldcontrib{$oldidx.':replyto'})) {
                $contrib{'replyto'} = $oldcontrib{$oldidx.':replyto'};
            }
            if (defined($oldcontrib{$oldidx.':history'})) {
                if ($oldcontrib{$oldidx.':history'} =~ /:/) {
                    my @oldversions = split(/:/,$oldcontrib{$oldidx.':history'});
                    $numoldver = @oldversions;
                } else {
                    $numoldver = 1;
                }
                $contrib{'history'} = $oldcontrib{$oldidx.':history'}.':';
            }
            my $numnewver = $numoldver + 1;
            if (defined($oldcontrib{$oldidx.':subject'})) {
                if ($oldcontrib{$oldidx.':subject'} =~ /^<version num="0">/) {
                    $contrib{'subject'} = '<version num="'.$numnewver.'">'.&HTML::Entities::encode($contrib{'subject'},'<>&"').'</version>';
                    $contrib{'subject'} = $oldcontrib{$oldidx.':subject'}.$contrib{'subject'};
                } else {
                    $contrib{'subject'} = '<version num="0">'.&HTML::Entities::encode($oldcontrib{$oldidx.':subject'},'<>&"').'</version><version num="1">'.&HTML::Entities::encode($contrib{'subject'},'<>&"').'</version>';
                }
            } 
            if (defined($oldcontrib{$oldidx.':message'})) {
                if ($oldcontrib{$oldidx.':message'} =~ /^<version num="0">/) {
                    $contrib{'message'} = '<version num="'.$numnewver.'">'.&HTML::Entities::encode($contrib{'message'},'<>&"').'</version>';
                    $contrib{'message'} = $oldcontrib{$oldidx.':message'}.$contrib{'message'};
                } else {
                    $contrib{'message'} = '<version num="0">'.&HTML::Entities::encode($oldcontrib{$oldidx.':message'},'<>&"').'</version><version num="1">'.&HTML::Entities::encode($contrib{'message'},'<>&"').'</version>';
                }
            }
            $contrib{'history'} .= $oldcontrib{$oldidx.':timestamp'};
            my $put_reply = &Apache::lonnet::putstore($env{'request.course.id'},
                  $oldsymb,$oldidx,\%contrib,
                  $env{'course.'.$env{'request.course.id'}.'.domain'},
                  $env{'course.'.$env{'request.course.id'}.'.num'});
            $status='Editing class discussion'.($anon?' (anonymous)':'');
        } else {
           $status='Adding to class discussion'.($anon?' (anonymous)':'').': '.
           &Apache::lonnet::store(\%contrib,$symb,$env{'request.course.id'},
                     $env{'course.'.$env{'request.course.id'}.'.domain'},
		     $env{'course.'.$env{'request.course.id'}.'.num'});
        }
        my %storenewentry=($symb => $now);
        $status.='<br />'.&mt('Updating discussion time').': '.
        &Apache::lonnet::put('discussiontimes',\%storenewentry,
                     $env{'course.'.$env{'request.course.id'}.'.domain'},
		     $env{'course.'.$env{'request.course.id'}.'.num'});
    }
    my %record=&getdiscussionrecords();
    my ($temp)=keys(%record);
    unless ($temp=~/^error\:/) {
       my %newrecord=();
       $newrecord{'resource'}=$symb;
       $newrecord{'subnumber'}=$record{'subnumber'}+1;
       $status.='<br />'.&mt('Registering').': '.
               &Apache::lonnet::cstore(\%newrecord,'_discussion');
       &updatekarma();
    }
    } else {
	$status.='Failed.';
    }
    return $status.'<br />';   
}


# Routine to get the complete discussion records

sub getdiscussionrecords {
    my ($uname,$udom,$course)=@_;
    unless ($uname) { $uname=$env{'user.name'}; }
    unless ($udom)  { $udom=$env{'user.domain'}; }
    unless ($course) { $course=$env{'request.course.id'}; }
    my %record=&Apache::lonnet::restore('_discussion',$course,$udom,$uname);
    return %record;
}

# Routine to get discussion statistics

sub getdiscussionstats {
    my %record=&getdiscussionrecords(@_);
    my $totalvotes = $record{'totallikes'} + $record{'totalunlikes'};
    return ($record{'subnumber'},$record{'points'},$record{'totallikes'},$totalvotes);
}

# Calculate discussion karma

sub calcdiscussionkarma {    
    my ($subs,$pts,$likes,$votes)=&getdiscussionstats(@_);
    my $karma=0;
    if ($votes>0) {
        $karma=int(.1+5.*(1.-exp(-$subs/10.))*$likes/$votes);
        if ($karma<0) { $karma=0; }
        if ($karma>5) { $karma=5; }
    }
    return $karma;
}

# Update karma

sub updatekarma {
    my ($uname,$udom,$course)=@_;
    unless ($uname) { $uname=$env{'user.name'}; }
    unless ($udom)  { $udom=$env{'user.domain'}; }
    unless ($course) { $course=$env{'request.course.id'}; }
    my $karma=&calcdiscussionkarma($uname,$udom,$course);
    &Apache::lonnet::cstore({ 'karma' => $karma },'_discussion',$course,$udom,$uname);
    &Apache::lonnet::do_cache_new('karma',$uname.':'.$udom.':'.$course,$karma,3600);
    return $karma;
}

# Retrieve karma

sub userkarma {
    my ($uname,$udom,$course)=@_;
    unless ($uname) { $uname=$env{'user.name'}; }
    unless ($udom)  { $udom=$env{'user.domain'}; }
    unless ($course) { $course=$env{'request.course.id'}; }
    my $hashkey=$uname.':'.$udom.':'.$course;
    my ($karma,$cached)=&Apache::lonnet::is_cached_new('karma',$hashkey);
    if ($cached) {
        return $karma;
    }
    my %userdisc=&getdiscussionrecords($uname,$udom,$course);
    $karma=$userdisc{'karma'};
    &Apache::lonnet::do_cache_new('karma',$hashkey,$karma,3600);
    return $karma;
}

# Store discussion credit

sub storediscussionpoints {
    my ($points,$uname,$udom,$course)=@_;
    unless ($points) { $points=0; }
    unless ($uname) { $uname=$env{'user.name'}; }
    unless ($udom)  { $udom=$env{'user.domain'}; }
    unless ($course) { $course=$env{'request.course.id'}; }
    my %record=('grader_user'   => $env{'user.name'},
                'grader_domain' => $env{'user.domain'},
                'points' => $points);
    return &Apache::lonnet::cstore(\%record,'_discussion',$course,$udom,$uname);
}

# Store discussion "likes"

sub storediscussionlikes {
    my ($chglikes,$chgunlikes,$uname,$udom,$course,$context)=@_;
    unless ($uname) { $uname=$env{'user.name'}; }
    unless ($udom)  { $udom=$env{'user.domain'}; }
    unless ($course) { $course=$env{'request.course.id'}; }
    my %record=&getdiscussionrecords($uname,$udom,$course);
    my $totallikes=$record{'totallikes'};
    my $totalunlikes=$record{'totalunlikes'};
    $totallikes += $chglikes;
    $totalunlikes += $chgunlikes;
    my %newrecord=('likes_user'   => $env{'user.name'},
                   'likes_domain' => $env{'user.domain'},
                   'totallikes'   => $totallikes,
                   'totalunlikes' => $totalunlikes,
                   'context'      => $context);
    my $status=&Apache::lonnet::cstore(\%newrecord,'_discussion',$course,$udom,$uname);
    if ($status eq 'ok') {
        &updatekarma($uname,$udom,$course);
    }
    return $status;
}

sub get_discussion_info {
    my ($idx,%contrib) = @_;
    my $changelast = 0;
    my $count = 0;
    my $hiddenflag = 0;
    my $deletedflag = 0;
    my ($hidden,$deleted,%info,$newlastdisc);
    my $version = $contrib{'version'};
    if ($version) {
        for (my $id=$version; $id>0; $id--) {
            my $vkeys=$contrib{$id.':keys'};
            my @keys=split(/:/,$vkeys);
            if (grep(/^hidden$/,@keys)) {
                if (!$hiddenflag) {
                    $hidden = $contrib{$id.':hidden'};
                    $hiddenflag = 1;
                }
            } elsif (grep(/^deleted$/,@keys)) {
                if (!$deletedflag) {
                    $deleted = $contrib{$id.':deleted'};
                    $deletedflag = 1;
                }
            } else {
                if (($hidden !~/\.$id\./) && ($deleted !~/\.$id\./)) {
                    $count++;
                    $info{$count}{'id'} = $id;
                    $info{$count}{'timestamp'}=$contrib{$id.':timestamp'}; 
                }
            }
        }
        if ($info{'1'}{'id'} == $idx) {
            $changelast = 1;
            if ($count > 1) { 
                $newlastdisc =  $info{'2'}{'timestamp'};
            } else {
                $newlastdisc = 0;
            }
        }
    }
    return ($changelast,$newlastdisc);
}

# ----------------------------------------------------------- Preview function

sub show_preview {
    my ($r) = @_;
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    my $start_page=
	&Apache::loncommon::start_page('Preview',undef,
				       {'only_body'   => 1,});

    my $message=&clear_out_html($env{'form.comment'});
    &newline_to_br(\$message);
    $message=&Apache::lonspeller::markeduptext($message);
    $message=&Apache::lontexconvert::msgtexconverted($message);
    my $subject=&clear_out_html($env{'form.subject'});
    $subject=~s/\n/\<br \/\>/g;
    $subject=&Apache::lontexconvert::msgtexconverted($subject);
					
    my $end_page = &Apache::loncommon::end_page();

    $r->print($start_page
             .'<h1>'.&mt('Preview').'</h1>'
             .&Apache::lonhtmlcommon::start_pick_box()
             .&Apache::lonhtmlcommon::row_title(&mt('Subject'))
             .$subject
             .&Apache::lonhtmlcommon::row_closure()
             .&Apache::lonhtmlcommon::row_title(&mt('Message'))
             .$message
             .&Apache::lonhtmlcommon::row_closure(1)
             .&Apache::lonhtmlcommon::end_pick_box()
             .$end_page
    );
}

sub contains_block_html {
    my ($message)=@_;
    return ($message =~ m{
        <(br|h1|h2|h3|h4|h5|h6|p|ol|ul|table|pre|address|blockquote|center|div) 
	  \s*
	 (\w+\=['"]\w+['"])*
	  \s*
	(
	  \s*/>|
	  >.*</\1\s*>
	)}xs 
    );
}

sub tidy_html {
	my ($message)=@_;
# 	my $tidy = HTML::Tidy::libXML->new();
# 	my $xhtml = $tidy->clean($message, 'utf-8', 1);
# 	$xhtml =~ m/<body>(.*)<\/body>/is;
# 	my $clean = $1;
# 	# remove any empty block-level tags
# 	$clean =~ s/<(table|p|div|tbody|blockquote|m|pre|algebra|center|ol|ul|span|h1|h2|h3|h4|h5|h6)\s*\/>//i;
# 	$message=$clean;
	return $message;
}

sub newline_to_br {
    my ($message)=@_;
    my $newmessage;
    my $parser=HTML::LCParser->new($message);
    while (my $token=$parser->get_token()) {
	if ($token->[0] eq 'T') {
	    my $text=$token->[1];
	    $text=~s/\n/\<br \/\>/g;
	    $newmessage.=$text;
	} elsif ($token->[0] eq 'D' || $token->[0] eq 'C') {
	    $newmessage.=$token->[1];
	} elsif ($token->[0] eq 'PI' || $token->[0] eq 'E') {
	    $newmessage.=$token->[2];
	} elsif ($token->[0] eq 'S') {
	    $newmessage.=$token->[4];
	}
	    
    }
    $$message=$newmessage;
}

sub generate_preview_button {
    my ($formname,$fieldname)=@_;
    unless ($formname) { $formname='mailform'; }
    unless ($fieldname) { $fieldname='comment'; }
    my $pre=&mt("Show Preview and Check Spelling");
    return(<<ENDPREVIEW);
<br />
<form name="preview" action="/adm/feedback?preview=1" method="post" target="preview">
<input type="hidden" name="subject" />
<input type="hidden" name="comment" />
<input type="button" value="$pre"
onclick="if (typeof(document.$formname.onsubmit)=='function') {document.$formname.onsubmit();};this.form.comment.value=document.$formname.$fieldname.value;this.form.subject.value=document.$formname.subject.value;this.form.submit();" />
</form>
ENDPREVIEW
}

sub modify_attachments {
    my ($r,$currnewattach,$currdelold,$symb,$idx,$attachmenturls,
        $attachmaxtext,$toolarge)=@_;

    my %lt = &Apache::lonlocal::texthash(
               'subj' => 'Subject',
               'chth' => 'Check the checkboxes for any you wish to remove.',
               'thef' => 'The following attachments have been uploaded for inclusion with this posting.',
               'adda' => 'Add a new attachment to this post',
               'stch' => 'Save Changes',
               'clic' => 'Add/remove attachments',
             );
    my $js = <<END;
<script type="text/javascript">
 function setAction () {
   document.modattachments.action = document.modattachments.origpage.value;
   document.modattachments.submit();
 }
</script>
<script type="text/javascript" src="/res/adm/includes/file_upload.js"></script>
END

    # Breadcrumbs
    my $brcrum = [{'href' => '',
                   'text' => 'Discussion Post Attachments'}];
    my %parms=('only_body' => 1);
    if ($env{'form.modal'} ne 'yes') { $parms{'bread_crumbs'} = $brcrum; }

    my $start_page = 
	&Apache::loncommon::start_page('Discussion Post Attachments',$js,\%parms);

    my $orig_subject = &unescape($env{'form.subject'});
    my $subject=&clear_out_html($orig_subject);
    $subject=~s/\n/\<br \/\>/g;
    $subject=&Apache::lontexconvert::msgtexconverted($subject);
    my $timestamp=$env{'form.timestamp'};
    my $numoldver=$env{'form.numoldver'};

    my $msg = '';
    my %attachments = ();
    my %currattach = ();
    if ($idx) {
        &extract_attachments($attachmenturls,$idx,$numoldver,\$msg,\%attachments,\%currattach,$currdelold);
    }
    &Apache::lonenc::check_encrypt(\$symb);

    my $end_page = 
	&Apache::loncommon::end_page();
				       
    $r->print(<<END);
$start_page
$toolarge
<form name="modattachments" method="post" enctype="multipart/form-data" action="/adm/feedback?attach=$symb">

 <h1>$lt{'clic'}</h1>
END
    $r->print(&Apache::lonhtmlcommon::start_pick_box());
    $r->print(&Apache::lonhtmlcommon::row_title(&mt('Subject')));
    $r->print('<b>'.$subject.'</b>');
    $r->print(&Apache::lonhtmlcommon::row_closure());
    $r->print(&Apache::lonhtmlcommon::row_title($lt{'adda'}));
    $r->print('<input type="file" name="addnewattach" class="LC_flUpload" />'
        .'<input type="hidden" id="LC_free_space" value="131072" />'
        .'<input type="button" name="upload" value="Upload" '
        .'onclick="this.form.submit()" />  '.$attachmaxtext);
    if(($idx)||(ref($currnewattach) eq 'ARRAY') && (@{$currnewattach} > 0)){
        $r->print(&Apache::lonhtmlcommon::row_closure());
        $r->print(&Apache::lonhtmlcommon::row_title(&mt('Attachments')));
        if ($idx) {
            if ($attachmenturls) {
                my @currold = keys(%currattach);
                if (@currold > 0) {
                    $r->print($lt{'thfo'}.'<br />'.$lt{'chth'}.'<br />'."\n");
                    foreach my $id (@currold) {
                        my $attachurl = &HTML::Entities::decode($attachments{$id}{'filename'});
                        $attachurl =~ m#/([^/]+)$#;
                        $r->print('<label><input type="checkbox" name="deloldattach" value="'.$id.'" />&nbsp;'.$1.'</label><br />'."\n");
                    }
                    $r->print("<br />");
                }
            }
        }
        if ((ref($currnewattach) eq 'ARRAY') && (@{$currnewattach} > 0)) {
            $r->print($lt{'chth'}.'<br />'."\n");
            foreach my $attach (@{$currnewattach}) {
                $attach =~ m#/([^/]+)$#;
                $r->print('<label><input type="checkbox" name="delnewattach" value="'.$attach.'" />&nbsp;'.$1.'</label><br />'."\n");
            }
        }
    }
    $r->print(&Apache::lonhtmlcommon::row_closure(1));
    $r->print(&Apache::lonhtmlcommon::end_pick_box());
    $r->print(<<END);
<input type="hidden" name="subject" value="$env{'form.subject'}" />
<input type="hidden" name="comment" value="$env{'form.comment'}" />
<input type="hidden" name="timestamp" value="$env{'form.timestamp'}" />
<input type="hidden" name="idx" value="$env{'form.idx'}" />
<input type="hidden" name="numoldver" value="$env{'form.numoldver'}" />
<input type="hidden" name="origpage" value="$env{'form.origpage'}" />
<input type="hidden" name="blog" value="$env{'form.blog'}" />
<input type="hidden" name="discuss" value="$env{'form.discuss'}" />
END
    foreach my $item (@{$currnewattach}) {
        $r->print('<input type="hidden" name="currnewattach" value="'.$item.'" />'."\n");
    }
    foreach my $item (@{$currdelold}) {
        $r->print('<input type="hidden" name="deloldattach" value="'.$item.'" />'."\n");
    }
    $r->print(<<END);
 <input type="button" name="rtntoedit" value="$lt{'stch'}" onclick="setAction()" />
</form>
$end_page
END
    return;
}

sub process_attachments {
    my ($currnewattach,$currdelold,$keepold) = @_;

    @{$currnewattach}=
	&Apache::loncommon::get_env_multiple('form.currnewattach');
    @{$currdelold}=
	&Apache::loncommon::get_env_multiple('form.deloldattach');
    if (exists($env{'form.delnewattach'})) {
        my @currdelnew =
	    &Apache::loncommon::get_env_multiple('form.delnewattach');
        my @currnew = ();
        foreach my $newone (@{$currnewattach}) {
            my $delflag = 0;
            foreach my $item (@currdelnew) {
                if ($newone eq $item) {
                    $delflag = 1;
                    last;
                }
            }
            unless ($delflag) {
                push(@currnew, $newone);
            }
        }
        @{$currnewattach} = @currnew;
    }
    @{$keepold} = &Apache::loncommon::get_env_multiple('form.keepold');
}

sub generate_attachments_button {
    my ($idx,$attachnum,$ressymb,$now,$currnewattach,$deloldattach,
        $numoldver,$mode,$blockblog) = @_;
    my $origpage = $ENV{'REQUEST_URI'};
    my $att=$attachnum.' '.&mt("attachments");
    my %lt = &Apache::lonlocal::texthash(
                'clic' => 'Add/remove attachments',
    ); 
    my $response = (<<END);
<br />
<form name="attachment" action="/adm/feedback?attach=$ressymb" method="post">
<input type="button" value="$lt{'clic'}"
onclick="if (typeof(document.mailform.onsubmit)=='function') {document.mailform.onsubmit();};this.form.comment.value=escape(document.mailform.comment.value);this.form.subject.value=escape(document.mailform.subject.value);
END
    if (!$blockblog) {
        $response .= 'setblogvalue();';
    }
    unless ($mode eq 'board') {
        $response .= 'javascript:anonchk();';
    }
    $response .= (<<ENDATTACH);
this.form.submit();" />
<input type="hidden" name="origpage" value="$origpage" />
<input type="hidden" name="idx" value="$idx" />
<input type="hidden" name="timestamp" value="$now" />
<input type="hidden" name="subject" />
<input type="hidden" name="comment" />
<input type="hidden" name="blog" value="0" />
<input type="hidden" name="discuss" value="0" />
<input type="hidden" name="numoldver" value="$numoldver" />
ENDATTACH
    if (defined($deloldattach)) {
        if (@{$deloldattach} > 0) {
            foreach my $delatt (@{$deloldattach}) {
                $response .= '<input type="hidden" name="deloldattach" value="'.$delatt.'" />'."\n";
            }
        }
    }
    if (defined($currnewattach)) {
        if (@{$currnewattach} > 0) {
            foreach my $attach (@{$currnewattach}) {
                $response .= '<input type="hidden" name="currnewattach" value="'.$attach.'" />'."\n";
            }
        }
    }
    $response .= '</form>';
    return $response;
}

sub extract_attachments {
    my ($attachmenturls,$idx,$numoldver,$message,$attachments,$currattach,$currdelold) = @_;
    %{$attachments}=();
    &get_post_attachments($attachments,$attachmenturls);
    foreach my $id (sort(keys(%{$attachments}))) {
        if (exists($$attachments{$id}{$numoldver})) {
            if (defined($currdelold)) {
                if (@{$currdelold} > 0) {
                    unless (grep/^$id$/,@{$currdelold}) {
                        $$currattach{$id} = $$attachments{$id}{$numoldver}; 
                    }
                } else {
                    $$currattach{$id} = $$attachments{$id}{$numoldver};
                }
            } else {
                $$currattach{$id} = $$attachments{$id}{$numoldver};
            }
        }
    }
    my @attached = (sort { $a <=> $b } keys(%{$currattach}));
    if (@attached == 1) {
        my $id = $attached[0];
        my $attachurl;
        if ($attachmenturls =~ m/^<attachment id="0">/) {
            $attachurl = &HTML::Entities::decode($$attachments{$id}{'filename'});
        } else {
            $attachurl = $$attachments{$id}{'filename'};
        }
        $attachurl=~m|/([^/]+)$|;
        $$message.='<br /><a href="'.$attachurl.'"><tt>'.
        $1.'</tt></a><br />';
        &Apache::lonnet::allowuploaded('/adm/feedback',
                               $attachurl);
    } elsif (@attached > 1) {
        $$message.='<ol>';
        foreach my $attach (@attached) {
            my $id = $attach;
            my $attachurl = &HTML::Entities::decode($$attachments{$id}{'filename'});
            my ($fname)
              =($attachurl=~m|/([^/]+)$|);
            $$message .= '<li><a href="'.$attachurl.
              '"><tt>'.
              $fname.'</tt></a></li>';
            &Apache::lonnet::allowuploaded('/adm/feedback',
                             $attachurl);
        }
        $$message .= '</ol>';
    }
}

sub construct_attachmenturl {
    my ($currnewattach,$keepold,$symb,$idx)=@_;
    my $oldattachmenturl;
    my $newattachmenturl;
    my $startnum = 0;
    my $currver = 0;
    if (($env{'form.editdisc'}) && ($idx)) {
        my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
                       $env{'course.'.$env{'request.course.id'}.'.domain'},
                       $env{'course.'.$env{'request.course.id'}.'.num'});
        $oldattachmenturl = $contrib{$idx.':attachmenturl'};
        if ($contrib{$idx.':history'}) {
            if ($contrib{$idx.':history'} =~ /:/) {
                my @oldversions = split(/:/,$contrib{$idx.':history'});
                $currver = 1 + scalar(@oldversions);
            } else {
                $currver = 2;
            }
        } else {
            $currver = 1;
        }
        if ($oldattachmenturl) {
            if ($oldattachmenturl =~ m/^<attachment id="0">/) {
                my %attachments = ();
                my $prevver = $currver-1;
                &get_post_attachments(\%attachments,$oldattachmenturl);
                my $numattach = scalar(keys(%attachments));
                $startnum += $numattach;
                foreach my $num (sort {$a <=> $b} keys(%attachments)) {
                    $newattachmenturl .= '<attachment id="'.$num.'"><filename>'.$attachments{$num}{'filename'}.'</filename>';
                    foreach my $item (sort {$a <=> $b} keys(%{$attachments{$num}})) {
                        unless ($item eq 'filename') {
                            $newattachmenturl .= '<post id="'.$item.'">'.$attachments{$num}{$item}.'</post>';
                        }
                    }
                    if (grep/^$num$/,@{$keepold}) {
                        $newattachmenturl .= '<post id="'.$currver.'">'.$attachments{$num}{$prevver}.'</post>';
                    }
                    $newattachmenturl .= '</attachment>';
                }
            } else {
                $newattachmenturl = '<attachment id="0"><filename>'.&HTML::Entities::encode($oldattachmenturl).'</filename><post id="0">n</post>';
                unless (grep/^0$/,@{$keepold}) {
                    $newattachmenturl .= '<post id="1">n</post>';
                }
                $newattachmenturl .= '</attachment>';
                $startnum ++;
            }
        }
    }
    for (my $i=0; $i<@{$currnewattach}; $i++) {
        my $attachnum = $startnum + $i;
        $newattachmenturl .= '<attachment id="'.$attachnum.'"><filename>'.&HTML::Entities::encode($$currnewattach[$i]).'</filename><post id="'.$currver.'">n</post></attachment>';
    }
    return $newattachmenturl; 
}

sub add_blog_checkbox {
    my ($crstype) = @_;
    my $checkstatus;
    if ($env{'form.blog'}) {
        $checkstatus = 'checked="checked"';
    }
    my $output = '
<script type="text/javascript">
function setblogvalue() {
    if (document.mailform.blog.checked) {
        document.attachment.blog.value = 1;
    } else {
        document.attachment.blog.value = 0;
    }
}
</script><br />
<label><input type="checkbox" name="blog" '.$checkstatus.' /> ';
    if ($crstype eq 'Community') {
        $output .= &mt('Add to my public community blog');
    } else {
        $output .= &mt('Add to my public course blog');
    } 
    $output .= '</label><br />'."\n";
    return $output;
}

sub has_discussion {
    my $resourcesref = shift;
    my $navmap = Apache::lonnavmaps::navmap->new();
    if (defined($navmap)) {
        my @allres=$navmap->retrieveResources();
        foreach my $resource (@allres) {
            if ($resource->hasDiscussion()) {
                my $ressymb = $resource->wrap_symb();
                if (ref($resourcesref) eq 'ARRAY') {
                    push(@{$resourcesref}, $ressymb);
                }
            }
        }
    } else {
        &Apache::lonnet::logthis('Has discussion check failed - could not create navmap object.');
    }
    return;
}

sub sort_filter_names {
    my ($sort_types,$role_types,$status_types,$crstype) = @_;
    if (ref($sort_types) eq 'HASH') {
        %{$sort_types} = (
                     ascdate => 'Date order - oldest first',
                     descdate => 'Date order - newest first',
                     thread => 'Threaded',
                     subject => 'By subject',
                     username => 'By domain and username',
                     lastfirst => 'By last name, first name'
                   );
    }
    my @courseroles = qw(st in ta ep ad);
    if ($crstype eq 'Community') {
        push(@courseroles,'co');
    } else {
        push(@courseroles,'cc');
    }
    if (ref($role_types) eq 'HASH') {
        foreach my $role (@courseroles) {
            $role_types->{$role} = &Apache::lonnet::plaintext($role,$crstype);
        }
        $role_types->{'all'} = 'All roles';
        $role_types->{'cr'} = 'Custom role';
    }
    if (ref($status_types) eq 'HASH') {
        %{$status_types} = (
                     all     => 'Roles of any status',
                     Active  => 'Only active roles',
                     Expired => 'Only past roles',
                     Future  => 'Only future roles',
                   );
    }
}
  
sub handler {
  my $r = shift;
  if ($r->header_only) {
     &Apache::loncommon::content_type($r,'text/html');
     $r->send_http_header;
     return OK;
  }

# --------------------------- Get query string for limited number of parameters

  &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
         ['like','unlike','modal','hide','unhide','deldisc','undeleteall','postdata','preview','replydisc','editdisc','cmd','symb','onlyunread','allposts','onlyunmark','previous','markread','markonread','markondisp','toggoff','toggon','modifydisp','changes','navtime','navmaps','navurl','sortposts','applysort','rolefilter','statusfilter','sectionpick','groupick','posterlist','userpick','attach','origpage','currnewattach','deloldattach','keepold','allversions','export','sendmessageonly','group','ref']);
  my $group = $env{'form.group'};
  my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
  my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};

  my %attachmax = (
                    text => &mt('(128 KB max size)'),
                    num  => 131072,
                  );
  if ($env{'form.editdisc'}) {
      if (!(&editing_allowed($env{'form.editdisc'},$group))) {
          my $symb=(split(/\:\:\:/,$env{'form.editdisc'}))[0];
          my ($map,$id,$url)=&Apache::lonnet::decode_symb($symb);
          my $feedurl=&Apache::lonnet::clutter($url);
          &redirect_back($r,$feedurl,&mt('Editing not permitted').'<br />',                     '0','0','','',$env{'form.previous'},undef,undef,undef,
                    undef,undef,undef,$group);
          return OK;
      }
  } 
  if ($env{'form.discsymb'}) {
      my ($symb,$feedurl) = &get_feedurl_and_clean_symb($env{'form.discsymb'});
      my $readkey = $symb.'_read';
      my $chgcount = 0;
      my %readinghash = &Apache::lonnet::get('nohist_'.$env{'request.course.id'}.'_discuss',[$readkey],$env{'user.domain'},$env{'user.name'});
      foreach my $key (keys(%env)) {
          if ($key =~ m/^form\.postunread_(\d+)/) {
              if ($readinghash{$readkey} =~ /\.$1\./) {
                  $readinghash{$readkey} =~ s/\.$1\.//;
                  $chgcount ++;
              }
          } elsif ($key =~ m/^form\.postread_(\d+)/) {
              unless ($readinghash{$readkey} =~ /\.$1\./) {
                  $readinghash{$readkey} .= '.'.$1.'.';
                  $chgcount ++;
              }
          }
      }
      if ($chgcount > 0) {
          &Apache::lonnet::put('nohist_'.$env{'request.course.id'}.'_discuss',
			  \%readinghash,$env{'user.domain'},$env{'user.name'});
      }
      &redirect_back($r,$feedurl,&mt('Marked postings read/unread').'<br />',
		     '0','0','','',$env{'form.previous'},'','','',
                     undef,undef,undef,$group);
      return OK;
  }
  if ($env{'form.allversions'}) {
      &Apache::loncommon::content_type($r,'text/html');
      &Apache::loncommon::no_cache($r);
      $r->send_http_header;

      # Breadcrumbs
      my $brcrum = [{'href' => '',
                     'text' => 'Discussion Post Versions'}];
      
      my %parms=();
      if ($env{'form.modal'} ne 'yes') { $parms{'bread_crumbs'} = $brcrum; }

      $r->print(&Apache::loncommon::start_page('Discussion Post Versions',undef,\%parms));

      my ($symb,$idx)=split(/\:\:\:/,$env{'form.allversions'});
      ($symb, my $feedurl)=&get_feedurl_and_clean_symb($symb);
      my $ressymb = &wrap_symb($symb);
      my $seeid;
      if (&Apache::lonnet::allowed('rin',$env{'request.course.id'}.($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:''))) {
          $seeid = 1;
      }
      my $seehidden = &can_see_hidden('',$ressymb,$feedurl,$group,$cdom,$cnum);
      if ($idx > 0) {
          my %messages = ();
          my %subjects = ();
          my %attachmsgs = ();
          my %allattachments = ();
          my %imsfiles = ();
          my ($screenname,$plainname,$showaboutme);
          my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
                                               $cdom,$cnum);
          $r->print(&get_post_contents(\%contrib,$idx,$seeid,$seehidden,'allversions',\%messages,\%subjects,\%allattachments,\%attachmsgs,\%imsfiles,\$screenname,\$plainname,\$showaboutme));
      }
      $r->print(&Apache::loncommon::end_page());
      return OK;
  }
  if ($env{'form.posterlist'}) {
      my ($symb,$feedurl)=&get_feedurl_and_clean_symb($env{'form.applysort'});
      &print_showposters($r,$symb,$env{'form.previous'},$feedurl,
			 $env{'form.sortposts'});
      return OK;
  }
  if ($env{'form.userpick'}) {
      my @posters = &Apache::loncommon::get_env_multiple('form.stuinfo');
      my ($symb,$feedurl)=&get_feedurl_and_clean_symb($env{'form.userpick'});
      my $numpicks = @posters;
      my %discinfo;
      $discinfo{$symb.'_userpick'} = join('&',@posters);
      &Apache::lonnet::put('nohist_'.$env{'request.course.id'}.'_discuss',
			   \%discinfo,$env{'user.domain'},$env{'user.name'});
      &redirect_back($r,$feedurl,&mt('Changed sort/filter').'<br />','0','0','',
		     '',$env{'form.previous'},$env{'form.sortposts'},'','','',
		     '',$numpicks,$group);
      return OK;
  }
  if ($env{'form.applysort'}) {
      my ($symb,$feedurl)=&get_feedurl_and_clean_symb($env{'form.applysort'});
      &redirect_back($r,$feedurl,&mt('Changed sort/filter').'<br />','0','0','',
		     '',$env{'form.previous'},$env{'form.sortposts'},
		     $env{'form.rolefilter'},$env{'form.statusfilter'},
		     $env{'form.sectionpick'},$env{'form.grouppick'},
                     undef,$group);
      return OK;
  } elsif ($env{'form.cmd'} eq 'sortfilter') {
      my ($symb,$feedurl)=&get_feedurl_and_clean_symb($env{'form.symb'});
      &print_sortfilter_options($r,$symb,$env{'form.previous'},$feedurl);
      return OK;
  } elsif ($env{'form.navtime'}) {
      my %discinfo = ();
      my @resources = ();
      if (defined($env{'form.navmaps'})) {
          if ($env{'form.navmaps'} =~ /:/) {
              @resources = split(/:/,$env{'form.navmaps'});
          } else {
              @resources = ("$env{'form.navmaps'}");
          }
      } else {
          &has_discussion(\@resources);
      }
      my $numitems = @resources;
      my $feedurl = '/adm/navmaps';
      if ($env{'form.navurl'}) { $feedurl .= '?'.$env{'form.navurl'}; }
      my %lt = &Apache::lonlocal::texthash(
          'twnp' => 'There are currently no resources or discussion boards with unread discussion postings.'
      );       
      foreach my $res (@resources) {
          my $ressymb=$res;
	  &Apache::lonenc::check_decrypt(\$ressymb);
          my $lastkey = $ressymb.'_lastread';
          $discinfo{$lastkey} = $env{'form.navtime'};
      }
      my $textline = '<b>'.
                     &mt('Marked "New" posts as read in a total of [_1] resources/discussion boards.',
                         $numitems).
                     '</b>';
      if ($numitems > 0) {
          &Apache::lonnet::put('nohist_'.$env{'request.course.id'}.'_discuss',
			     \%discinfo,$env{'user.domain'},$env{'user.name'});
      } else {
          $textline = "<b>$lt{'twnp'}</b>";
      }
      &Apache::loncommon::content_type($r,'text/html');
      $r->send_http_header;
      my $logo=&Apache::loncommon::lonhttpdurl('/adm/lonIcons/lonlogos.gif');
      my %onload;

      my $start_page=
	  &Apache::loncommon::start_page('New posts marked as read',undef,
					 {'redirect'    => [2,$feedurl],
					  'only_body'   => 1,
					  'add_entries' => \%onload});
      my $end_page = &Apache::loncommon::end_page();
      $r->print (<<ENDREDIR);
$start_page
<img align="right" src="$logo" />
$textline
<form name="reldt" action="$feedurl" target="loncapaclient">
</form>
<br />
$end_page
ENDREDIR
      return OK;
  } elsif ($env{'form.modifydisp'}) {
      my ($symb,$feedurl)=&get_feedurl_and_clean_symb($env{'form.modifydisp'});
      my ($dispchgA,$dispchgB,$markchg,$toggchg) = 
	  split(/_/,$env{'form.changes'});
      &print_display_options($r,$symb,$env{'form.previous'},$dispchgA,
			     $dispchgB,$markchg,$toggchg,$feedurl);
      return OK;
  } elsif ($env{'form.markondisp'} || $env{'form.markonread'} ||
	   $env{'form.allposts'}   || $env{'form.onlyunread'} ||
	   $env{'form.onlyunmark'} || $env{'form.toggoff'}    ||
	   $env{'form.toggon'}     || $env{'form.markread'}) {
      my ($symb,$feedurl)=&get_feedurl_and_clean_symb($env{'form.symb'});
      my %discinfo;
# ------------------------ Modify setting for read/unread toggle for each post 
      if ($env{'form.toggoff'}) { $discinfo{$symb.'_readtoggle'}=0; }
      if ($env{'form.toggon'})  { $discinfo{$symb.'_readtoggle'}=1; }
# --------- Modify setting for identification of 'NEW' posts in this discussion
      if ($env{'form.markondisp'}) {
	  $discinfo{$symb.'_lastread'} = time;
	  $discinfo{$symb.'_markondisp'} = 1;
      }
      if ($env{'form.markonread'}) {
	  if ( $env{'form.previous'} > 0 ) {
	      $discinfo{$symb.'_lastread'} = $env{'form.previous'};
	  }
	  $discinfo{$symb.'_markondisp'} = 0;
      }
# --------------------------------- Modify display setting for this discussion 
      if ($env{'form.allposts'}) {
	  $discinfo{$symb.'_showonlyunread'} = 0;
	  $discinfo{$symb.'_showonlyunmark'} = 0;
      }
      if ($env{'form.onlyunread'}) { $discinfo{$symb.'_showonlyunread'} = 1;  }
      if ($env{'form.onlyunmark'}) { $discinfo{$symb.'_showonlyunmark'} = 1;  }
# ----------------------------------------------------- Mark new posts not NEW 
      if ($env{'form.markread'})   { $discinfo{$symb.'_lastread'} = time; }
      &Apache::lonnet::put('nohist_'.$env{'request.course.id'}.'_discuss',
			   \%discinfo,$env{'user.domain'},$env{'user.name'});
      my $previous=$env{'form.previous'};
      if ($env{'form.markondisp'}) { $previous=undef; }
      &redirect_back($r,$feedurl,&mt('Changed display status').'<br />',
		     '0','0','','',$previous,'','','','','','',$group);
      return OK;
  } elsif (($env{'form.hide'}) || ($env{'form.unhide'})) {
# ----------------------------------------------------------------- Hide/unhide
      my $entry=$env{'form.hide'}?$env{'form.hide'}:$env{'form.unhide'};
      my ($symb,$idx)=split(/\:\:\:/,$entry);
      ($symb,my $feedurl)=&get_feedurl_and_clean_symb($symb);
      my $ressymb = &wrap_symb($symb);

      my $seehidden = &can_see_hidden('',$ressymb,$feedurl,$group,$cdom,$cnum);
      unless (($seehidden) || (&editing_allowed($env{'form.hide'},$group))) {
          &redirect_back($r,$feedurl,&mt('Hiding not permitted').'<br />',
                         '0','0','','',$env{'form.previous'},'','','','',
                         undef,undef,$group,);
          return OK;
      }

      my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
                                           $cdom,$cnum);

      my $currenthidden=$contrib{'hidden'};
      my $currentstudenthidden=$contrib{'studenthidden'};

      if ($env{'form.hide'}) {
	  $currenthidden.='.'.$idx.'.';
	  unless ($seehidden) {
	      $currentstudenthidden.='.'.$idx.'.';
	  }
      } else {
	  $currenthidden=~s/\.$idx\.//g;
      }
      my %newhash=('hidden' => $currenthidden);
      if ( ($env{'form.hide'}) && (!$seehidden) ) {
	  $newhash{'studenthidden'} = $currentstudenthidden;
      }
      if ($env{'form.hide'}) {
          my $changelast = 0;
          my $newlast;
          ($changelast,$newlast) = &get_discussion_info($idx,%contrib);
          if ($changelast) {
              &Apache::lonnet::put('discussiontimes',{$symb => $newlast},
                                   $cdom,$cnum);
          }
      }
      my $result;
      if (&Apache::lonnet::store(\%newhash,$symb,$env{'request.course.id'},
                                 $cdom,$cnum) eq 'ok') {
          my $prefix=$symb.':'.$idx.':';
          my %likes=&Apache::lonnet::dump('disclikes',$cdom,$cnum,
                                          '^'.$prefix);
          my ($totallikes,$totalunlikes);
          if (ref($likes{$prefix.'likers'}) eq 'HASH') {
              $totallikes = scalar(keys(%{$likes{$prefix.'likers'}}));
          }
          if (ref($likes{$prefix.'unlikers'}) eq 'HASH') {
              $totalunlikes = scalar(keys(%{$likes{$prefix.'unlikers'}}));
          }
          if ($totallikes || $totalunlikes) {
              my ($chglikes,$chgunlikes,$context);
              if ($env{'form.hide'}) {
                  $chglikes = -1 * $totallikes;
                  $chgunlikes = -1 * $totalunlikes;
                  $context = 'hide';
              } else {
                  $chglikes = $totallikes;
                  $chgunlikes = $totalunlikes;
                  $context = 'unhide';
              }
              &storediscussionlikes($chglikes,$chgunlikes,
                                    $contrib{$idx.':sendername'},
                                    $contrib{$idx.':senderdomain'},
                                    $env{'request.course.id'},
                                    $context);
          
          }
          $result = &mt('Changed discussion status');
      } else {
          $result = &mt('Discussion status unchanged'); 
      }
      &redirect_back($r,$feedurl,$result.'<br />','0','0','','',
		     $env{'form.previous'},undef,undef,undef,
                     undef,undef,undef,$group);
      return OK;
  } elsif (($env{'form.like'}) || ($env{'form.unlike'})) {
# ----------------------------------------------------------------- Like/unlike
      my $entry=$env{'form.like'}?$env{'form.like'}:$env{'form.unlike'};
      my ($symb,$idx)=split(/\:\:\:/,$entry);
      ($symb,my $feedurl)=&get_feedurl_and_clean_symb($symb);
      my $result;
      if ($idx > 0) {
          my $realsymb = &get_realsymb($symb);
          my $status='OPEN';
          if ($Apache::lonhomework::parsing_a_problem ||
              $Apache::lonhomework::parsing_a_task) {
              $status=$Apache::inputtags::status[-1];
          }
          if (&discussion_vote_available($status,$realsymb)) {
              my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
                                                   $cdom,$cnum);
              my $ownpost;
              if (($contrib{$idx.':sendername'} eq $env{'user.name'}) && 
                  ($contrib{$idx.':senderdomain'} eq $env{'user.domain'})) {
                  $ownpost = 1;
              }
              if ($ownpost || $contrib{$idx.':hidden'} || $contrib{$idx.':deleted'}) {
                  $result = &mt('Vote not registered.').' ';
              }
              if ($ownpost) {
                  $result .= &mt('No voting for your own posts.');
              } elsif ($contrib{$idx.':hidden'}) {
                  $result .= &mt('No voting for hidden posts.');
              } elsif ($contrib{$idx.':deleted'}) {
                  $result .= &mt('No voting for deleted posts.');
              } else {
#
# Likes and unlikes are in db-file "disclikes" of the course
# The prefix is the $symb to identify the resource discussion,
# and the $idx to identify the entry
#
                  my $prefix=$symb.':'.$idx.':';
                  my %likes=&Apache::lonnet::dump('disclikes',$cdom,$cnum,
                                                  '^'.$prefix);

# Get current like or unlike status for the $idx for this user.
                  my $thisuser=$env{'user.name'}.':'.$env{'user.domain'};
                  my ($userlikes,$userunlikes);
                  if (ref($likes{$prefix.'likers'}) eq 'HASH') {
                      if (exists($likes{$prefix.'likers'}{$thisuser})) {
                          $userlikes = 1;
                      }
                  }
                  if (ref($likes{$prefix.'unlikers'}) eq 'HASH') {
                      if (exists($likes{$prefix.'unlikers'}{$thisuser})) {
                          $userunlikes = 1;
                      }
                  }
# Get the current "likes" count
                  my $likescount=$likes{$prefix.'likes'};
# Find out if they already voted
# Users cannot like a post twice, or unlike it twice.
# They can change their mind, though.
                  my $alreadyflag=0;
                  my $votetype;
                  if ($env{'form.like'}) {
                      if ($userlikes) {
                          $alreadyflag=1;
                      } elsif ($userunlikes) {
                          delete($likes{$prefix.'unlikers'}{$thisuser});
                          $votetype = 'switch';
                          $likescount++;
                      } else {
                          if (ref($likes{$prefix.'likers'}) eq 'HASH') {
                              $likes{$prefix.'likers'}{$thisuser} = 1;
                          } else {
                              $likes{$prefix.'likers'} = {$thisuser => 1};
                          }
                          $likescount++;
                      }
                  } else {
                      if ($userunlikes) {
                          $alreadyflag=1;
                      } elsif ($userlikes) {
                          delete($likes{$prefix.'likers'}{$thisuser});
                          $votetype = 'switch';
                          $likescount--;
                      } else {
                          if (ref($likes{$prefix.'unlikers'}) eq 'HASH') {
                              $likes{$prefix.'unlikers'}{$thisuser} = 1;
                          } else {
                              $likes{$prefix.'unlikers'} = {$thisuser => 1};
                          }
                          $likescount--;
                      }
                  }
# $alreadyflag would be 1 if they tried to double-like or double-unlike
                  if ($alreadyflag) {
                      if ($env{'form.like'}) {
                          $result= &mt("'Like' already registered");
                      } else {
                          $result= &mt("'Unlike' already registered");
                      }
                  } else {
                      my %newhash=($prefix.'likes'    => $likescount,
                                   $prefix.'likers'   => $likes{$prefix.'likers'},
                                   $prefix.'unlikers' => $likes{$prefix.'unlikers'});
# Store data in db-file "disclikes"
                      if (&Apache::lonnet::put('disclikes',\%newhash,$cdom,$cnum) eq 'ok') {
# Also store with the person who posted the liked/unliked entry
                          my ($chglike,$chgunlike);
                          if ($env{'form.like'}) {
                              if ($votetype eq 'switch') {
                                  $chglike = 0;
                                  $chgunlike = -1;
                              } else {
                                  $chglike = 1;
                                  $chgunlike = 0;
                              } 
                              &storediscussionlikes($chglike,$chgunlike,
                                                    $contrib{$idx.':sendername'},
                                                    $contrib{$idx.':senderdomain'},
                                                    $env{'request.course.id'},'like');
                              $result=&mt("Registered 'Like'");
                          } else {
                              if ($votetype eq 'switch') {
                                  $chglike = -1;
                                  $chgunlike = 0;
                              } else {
                                  $chglike = 0;
                                  $chgunlike = 1;
                              }
                             &storediscussionlikes($chglike,$chgunlike,
                                                   $contrib{$idx.':sendername'},
                                                   $contrib{$idx.':senderdomain'},
                                                   $env{'request.course.id'},'unlike');
                             $result=&mt("Registered 'Unlike'");
                          }
                      } else {
# Oops, something went wrong
                          $result=&mt("Failed to register vote");
                      }
                  }
              }
          } else {
              $result=&mt('Voting unavailable for this discussion');
          }
      } else {
          $result=&mt('Invalid post number'); 
      }
      &redirect_back($r,$feedurl,$result.'<br />',
                     '0','0','','',$env{'form.previous'},undef,undef,undef,
                     undef,undef,undef,$group);
      return OK;
  } elsif ($env{'form.cmd'}=~/^(threadedoff|threadedon)$/) {
      my ($symb,$feedurl)=&get_feedurl_and_clean_symb($env{'form.symb'});
      if ($env{'form.cmd'} eq 'threadedoff') {
	  &Apache::lonnet::put('environment',{'unthreadeddiscussion' => 'on'});
	  &Apache::lonnet::appenv({'environment.unthreadeddiscussion' => 'on'});
	  &Apache::lonnet::del('environment',['threadeddiscussion']);
	  &Apache::lonnet::delenv('environment.threadeddiscussion');
      } else {
	  &Apache::lonnet::put('environment',{'threadeddiscussion' => 'on'});
	  &Apache::lonnet::appenv({'environment.threadeddiscussion' => 'on'});
	  &Apache::lonnet::del('environment',['unthreadeddiscussion']);
	  &Apache::lonnet::delenv('environment.unthreadeddiscussion');
      }
      &redirect_back($r,$feedurl,&mt('Changed discussion view mode').'<br />',
		     '0','0','','',$env{'form.previous'},undef,undef,undef,
                     undef,undef,undef,$group);
      return OK;
  } elsif ($env{'form.deldisc'}) {
# --------------------------------------------------------------- Hide for good
      my ($symb,$idx)=split(/\:\:\:/,$env{'form.deldisc'});
      ($symb,my $feedurl)=&get_feedurl_and_clean_symb($symb);
      my $ressymb=&wrap_symb($symb);

      unless (&can_see_hidden('',$ressymb,$feedurl,$group,$cdom,$cnum)) {
          &redirect_back($r,$feedurl,&mt('Deletion not permitted').'<br />',
                         '0','0','','',$env{'form.previous'},'','','','',
                         undef,undef,$group);
          return OK;
      }
      my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
                                           $cdom,$cnum);
      my ($changelast,$newlast) = &get_discussion_info($idx,%contrib);
      if ($changelast) {
          &Apache::lonnet::put('discussiontimes',{$symb => $newlast},
                               $cdom,$cnum);
      }
      my %newhash=('deleted' => $contrib{'deleted'}.".$idx.");

      my $result;
      if (&Apache::lonnet::store(\%newhash,$symb,$env{'request.course.id'},
                             $cdom,$cnum) eq 'ok') {
          $result = &mt('Changed discussion status');
          my $prefix=$symb.':'.$idx.':';
          my %likes=&Apache::lonnet::dump('disclikes',$cdom,$cnum,
                                          '^'.$prefix);
          my ($totallikes,$totalunlikes);
          if (ref($likes{$prefix.'likers'}) eq 'HASH') {
              $totallikes = scalar(keys(%{$likes{$prefix.'likers'}}));
          }
          if (ref($likes{$prefix.'unlikers'}) eq 'HASH') {
              $totalunlikes = scalar(keys(%{$likes{$prefix.'unlikers'}}));
          }
          if ($totallikes || $totalunlikes) {
              my $chglikes = -1 * $totallikes;
              my $chgunlikes = -1 * $totalunlikes;
              &storediscussionlikes($chglikes,$chgunlikes,
                                    $contrib{$idx.':sendername'},
                                    $contrib{$idx.':senderdomain'},
                                    $env{'request.course.id'},
                                    'delete');
          }
      } else {
          $result = &mt('Discussion status unchanged');
      } 
      &redirect_back($r,$feedurl,$result.'<br />','0','0','','',
		     $env{'form.previous'},undef,undef,undef,
                     undef,undef,undef,$group);
      return OK;
  } elsif ($env{'form.preview'}) {
# -------------------------------------------------------- User wants a preview
      &show_preview($r);
      return OK;
  } elsif ($env{'form.attach'}) {
# -------------------------------------------------------- Work on attachments
      &Apache::loncommon::content_type($r,'text/html');
      $r->send_http_header;
      &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['subject','comment','addnewattach','delnewattach','timestamp','numoldver','idx','discuss','blog']);
      my (@currnewattach,@currdelold,@keepold,$toolarge);
      &process_attachments(\@currnewattach,\@currdelold,\@keepold);
      if (exists($env{'form.addnewattach.filename'})) {
          if (length($env{'form.addnewattach'})<=$attachmax{'num'}) {
              my $subdir = 'feedback/'.$env{'form.timestamp'};
              my $newattachment=&Apache::lonnet::userfileupload('addnewattach',undef,$subdir);
	      push(@currnewattach, $newattachment);
          } else {
              $toolarge = '<p><span class="LC_warning">'.&mt('Attachment not included - exceeded permitted length').'</span><br /></p>';
          }
      }
      my $attachmenturls;
      my ($symb) = &get_feedurl_and_clean_symb($env{'form.attach'});
      my $idx = $env{'form.idx'};
      if ($idx) {
          my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
                                               $cdom,$cnum);
          $attachmenturls = $contrib{$idx.':attachmenturl'};
      }
      &modify_attachments($r,\@currnewattach,\@currdelold,$symb,$idx,
			  $attachmenturls,$attachmax{'text'},$toolarge);
      return OK;
  } elsif ($env{'form.export'}) {
      &Apache::loncommon::content_type($r,'text/html');
      $r->send_http_header;
      my ($symb,$feedurl) = &get_feedurl_and_clean_symb($env{'form.export'});
      my $mode='board';
      my $status='OPEN';
      my $previous=$env{'form.previous'};
      if ($feedurl =~ /$LONCAPA::assess_re/) {
          $mode='problem';
          $status=$Apache::inputtags::status[-1];
      }
       
      my $discussion = &list_discussion($mode,$status,$symb); 
      my $start_page = 
	  &Apache::loncommon::start_page('Resource Feedback and Discussion');
      my $end_page = 
	  &Apache::loncommon::end_page();
      $r->print($start_page.$discussion.$end_page);
      return OK;

  } elsif ($env{'form.undeleteall'}) {
      &Apache::loncommon::content_type($r,'text/html');
      $r->send_http_header;
      my ($symb,$feedurl) = &get_feedurl_and_clean_symb($env{'form.undeleteall'});
      my $ressymb=&wrap_symb($symb);
      $r->print(&Apache::loncommon::start_page('Undelete all deleted discussion entries'));
      if (&can_see_hidden('',$ressymb,$feedurl,$group,$cdom,$cnum)) {
          my %contrib=&Apache::lonnet::restore($symb,$env{'request.course.id'},
                                                $cdom,$cnum);
          $contrib{'deleted'} =~ s/^\.//;
          $contrib{'deleted'} =~ s/\.$//;
          my $confirm_msg;
          if ($contrib{'deleted'} ne '') {
              if (&Apache::lonnet::store({'deleted' => ''},$symb,$env{'request.course.id'},
                                          $cdom,$cnum) eq 'ok') {
                  my %likes=&Apache::lonnet::dump('disclikes',$cdom,$cnum,'^'.$symb.':');
                  my @ids = split(/\.\./,$contrib{'deleted'});
                  my (%chglikes,%chgunlikes);
                  foreach my $idx (@ids) {
                      my $uname = $contrib{$idx.':sendername'};
                      my $udom = $contrib{$idx.':senderdomain'};
                      my ($totallikes,$totalunlikes);
                      if (ref($likes{$symb.':'.$idx.':likers'}) eq 'HASH') {
                          $totallikes = scalar(keys(%{$likes{$symb.':'.$idx.':likers'}}));
                      }
                      if (ref($likes{$symb.':'.$idx.':unlikers'}) eq 'HASH') {
                          $totalunlikes = scalar(keys(%{$likes{$symb.':'.$idx.':unlikers'}}));
                      }
                      if ($totallikes || $totalunlikes) {
                          $chglikes{$uname.':'.$udom} += $totallikes;
                          $chgunlikes{$uname.':'.$udom} += $totalunlikes;
                      }
                  }
                  foreach my $user (keys(%chglikes)) {
                      my ($uname,$udom) = split(/:/,$user);
                      &storediscussionlikes($chglikes{$user},$chgunlikes{$user},
                                            $uname,$udom,$env{'request.course.id'},
                                            'undelete');
                  }
                  $confirm_msg = &Apache::lonhtmlcommon::confirm_success(&mt("Undeleted all entries"));
              } else {
                  $confirm_msg = &Apache::lonhtmlcommon::confirm_success(&mt("Failed to undelete entries"),1);
              }
          } else {
              $confirm_msg = &Apache::lonhtmlcommon::confirm_success(&mt("No entries to undelete"),1);
          }
          $r->print(
              '<br />'
             .&Apache::loncommon::confirmwrapper($confirm_msg)
             .&Apache::lonhtmlcommon::actionbox(
                  ["<a href='$feedurl'>".&mt("Return and reload")."</a>"])
          );
      }
      $r->print(&Apache::loncommon::end_page());
      return OK;
  } else {
# ------------------------------------------------------------- Normal feedback
      my $feedurl=$env{'form.postdata'};
      $feedurl=~s/^https?\:\/\///;
      $feedurl=~s/^$ENV{'SERVER_NAME'}//;
      $feedurl=~s/^$ENV{'HTTP_HOST'}//;
      $feedurl=~s/\?.+$//;

      my $symb;
      if ($env{'form.replydisc'}) {
	  $symb=(split(/\:\:\:/,$env{'form.replydisc'}))[0];
      } elsif ($env{'form.editdisc'}) {
	  $symb=(split(/\:\:\:/,$env{'form.editdisc'}))[0];
      } elsif ($env{'form.origpage'}) {
	  $symb=""; 
      } elsif ($env{'form.sendmessageonly'}) {
          $symb=(split(/\:\:\:/,$env{'form.sendmessageonly'}))[0];
      } else {
	  $symb=&Apache::lonnet::symbread($feedurl);
      }
      unless ($symb) {
	  $symb=$env{'form.symb'};
      }
      if (defined($symb)) {
          ($symb,$feedurl)=&get_feedurl_and_clean_symb($symb);
      } else {
          # backward compatibility (bulletin boards used to be 'wrapped')
          &Apache::lonenc::check_decrypt(\$feedurl);
          &dewrapper(\$feedurl);
      }
      my $goahead=1;
      if ($feedurl=~/$LONCAPA::assess_re/) {
	  unless ($symb) { $goahead=0; }
      }
      if (!$goahead) {
          # Ambiguous Problem Resource
	  $r->internal_redirect('/adm/ambiguous');
	  return OK;
      }
# Go ahead with feedback, no ambiguous reference
      unless (
	  (
	   ($feedurl=~m:^/res:) && ($feedurl!~m:^/res/adm:)
	   ) 
	  || 
	  ($env{'request.course.id'} && ($feedurl!~m:^/adm:))
	  ||
	  ($env{'request.course.id'} && ($symb=~/^bulletin\_\_\_/))
          ||
          (($env{'request.course.id'}) && ($feedurl =~ /ext\.tool$/))
	  ) {
	  &Apache::loncommon::content_type($r,'text/html');
	  $r->send_http_header;
# Unable to give feedback
          &Apache::lonenc::check_encrypt(\$feedurl);
	  &no_redirect_back($r,$feedurl);
	  return OK;
      }
# --------------------------------------------------- Print login screen header
      unless ($env{'form.sendit'}) {
          &Apache::lonenc::check_encrypt(\$feedurl);
	  &Apache::loncommon::content_type($r,'text/html');
	  $r->send_http_header;
          if (($env{'form.replydisc'}) || ($env{'form.editdisc'})) {
              my ($blocked,$blocktext) = 
                     &Apache::loncommon::blocking_status('boards');
              if ($blocked) {
                  $r->print(&blocked_reply_or_edit($blocktext));
                  return OK;
              }
          }
	  my $options=&screen_header($feedurl,$symb,$group);
	  if ($options) {
	      &mail_screen($r,$feedurl,$options,$symb,$attachmax{'text'});
	  } else {
	      &fail_redirect($r,$feedurl);
	  }
	  return OK;
      }
      
# Get previous user input
      my $prevattempts=&Apache::loncommon::get_previous_attempt(
                                   $symb,$env{'user.name'},$env{'user.domain'},
				   $env{'request.course.id'});

# Get output from resource
      &Apache::lonenc::check_encrypt(\$feedurl);
      my $usersaw=&resource_output($feedurl);

# Get resource answer (need to allow student to view grades for this to work)
      &Apache::lonnet::appenv({'allowed.vgr'=>'F'});
      my $usersymb = &Apache::lonenc::check_encrypt($symb);
      my $useranswer=
          &Apache::loncommon::get_student_answers(
              $usersymb,$env{'user.name'},$env{'user.domain'},
              $env{'request.course.id'});
      &Apache::lonnet::delenv('allowed.vgr');
# Get attachments, if any, and not too large
      my $attachmenturl='';
      my $toolarge='';
      if (($env{'form.origpage'}) || ($env{'form.editdisc'}) ||
	  ($env{'form.replydisc'})) {
	  my ($symb,$idx);
	  if ($env{'form.replydisc'}) {
	      ($symb,$idx)=split(/\:\:\:/,$env{'form.replydisc'});
	  } elsif ($env{'form.editdisc'}) {
	      ($symb,$idx)=split(/\:\:\:/,$env{'form.editdisc'});
	  } elsif ($env{'form.origpage'}) {
	      $symb = $env{'form.symb'};
	  }
	  &Apache::lonenc::check_decrypt(\$symb);
	  my @currnewattach = ();
	  my @deloldattach = ();
	  my @keepold = ();
	  &process_attachments(\@currnewattach,\@deloldattach,\@keepold);
	  $symb=~s|(bulletin___\d+___)adm/wrapper/|$1|;
	  $attachmenturl=&construct_attachmenturl(\@currnewattach,\@keepold,$symb,$idx);
      } elsif ($env{'form.attachment.filename'}) {
	  if (length($env{'form.attachment'})<=$attachmax{'num'}) {
              my $now = time;
              my $subdir = 'feedback/'.$now;
	      $attachmenturl=&Apache::lonnet::userfileupload('attachment',undef,$subdir);
	  } else {
              $toolarge = '<p><span class="LC_warning">'.&mt('Attachment not included - exceeded permitted length').'</span><br /></p>';
          }
      }
# Filter HTML out of message (could be nasty)
      my $override;
      if ($env{'form.discuss'} =~ /^(?:author|question|course|policy)$/) {
          $override = 1;
      }
      my $message=&clear_out_html($env{'form.comment'},$override);

# Assemble email
      my ($email,$citations)=&assemble_email($message,$prevattempts,
					     $usersaw,$useranswer);
 
# Who gets this?
      my ($typestyle,%to) = &Apache::lonmsg::decide_receiver($feedurl);

# Actually send mail
      my ($status,$numsent)=&send_msg(&clear_out_html($env{'form.subject'}),
				      $feedurl,$email,$citations,
				      $attachmenturl,$usersymb,%to);

# Discussion? Store that.
      my $numpost=0;
      if (  ($env{'form.discuss'} ne ''
	     && $env{'form.discuss'} !~ /^(?:author|question|course|policy)/)
	   || $env{'form.anondiscuss'} ne '') {
	  my $subject = &clear_out_html($env{'form.subject'});
	  my $anonmode=($env{'form.discuss'} eq 'anon' || $env{'form.anondiscuss'} );
	  $typestyle.=&adddiscuss($symb,$message,$anonmode,$attachmenturl,
				  $subject,$group);
	  $numpost++;
      }

# Add to blog?

      my $blog='';
      if ($env{'form.blog'}) {
	  my $subject = &clear_out_html($env{'form.subject'});
	  $status.=&Apache::lonrss::addentry($env{'user.name'},
				    $env{'user.domain'},
				    'CourseBlog_'.$env{'request.course.id'},
				    $subject,$message,$feedurl,'public');
          if (&Apache::loncommon::course_type() eq 'Community') {
              $blog='<br />'.&mt('Added to my community blog').'<br />';
          } else {
	      $blog='<br />'.&mt('Added to my course blog').'<br />';
          }
      }
	  
# Receipt screen and redirect back to where came from
      &redirect_back($r,$feedurl,$typestyle,$numsent,$numpost,$blog,$status,$env{'form.previous'},undef,undef,undef,undef,undef,undef,$group,$toolarge);
  }
  return OK;
}

sub blocked_reply_or_edit {
    my ($blocktext) = @_;
    return 
      &Apache::loncommon::start_page('Resource Feedback and Discussion').
      $blocktext.'<br /><br /><a href="javascript:history.go(-1)">'.
      &mt('Back to previous page').
      &Apache::loncommon::end_page();
} 

sub wrap_symb {
    my ($ressymb)=@_;
    if ($ressymb =~ /bulletin___\d+___/) {
        unless ($ressymb =~ m|bulletin___\d+___adm/wrapper|) {
            $ressymb=~s|(bulletin___\d+___)|$1adm/wrapper|;
        }
    }
    return $ressymb;
}

sub dewrapper {
    my ($feedurl)=@_;
    if ($$feedurl=~m|^/adm/wrapper/adm/.*/bulletinboard$|) {
        $$feedurl=~s|^/adm/wrapper||;
    }
}

sub get_feedurl {
    my ($symb)=@_;
    my ($map,$ind,$url)=&Apache::lonnet::decode_symb($symb);
    my $feedurl = &Apache::lonnet::clutter($url);
    &dewrapper(\$feedurl);
    return $feedurl;
}

sub get_feedurl_and_clean_symb {
    my ($symb)=@_;
    &Apache::lonenc::check_decrypt(\$symb);
# backward compatibility (bulletin boards used to be 'wrapped')
    unless ($symb =~ m|bulletin___\d+___adm/wrapper|) {
	$symb=~s|(bulletin___\d+___)|$1adm/wrapper|;
    }
    my $feedurl = &get_feedurl($symb);
    return ($symb,$feedurl);
}

sub editing_allowed {
    my ($postid,$group) = @_;
    $postid = &unescape($postid);
    my $can_edit = 0;
    if ($group ne '') {
        my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
        my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
        if ($postid =~ m|^bulletin___\d+___adm/wrapper(/adm/\Q$cdom\E/\Q$cnum\E/\d+/bulletinboard)|) {
            if (&check_group_priv($group,'egp') eq 'ok') {
                $can_edit = 1;
            }
            return $can_edit;
        }     
    } 
    my $cid = $env{'request.course.id'};
    my $role = (split(/\./,$env{'request.role'}))[0];
    my $section = $env{'request.course.sec'};
    my $allow_editing_config = 
	$env{'course.'.$cid.'.allow_discussion_post_editing'};
    if ($allow_editing_config =~ m/^\s*yes\s*$/i) {
        $can_edit = 1;
    } else {
	foreach my $editor (split(/,/,$allow_editing_config)) {
	    my ($editor_role,$editor_sec) = split(/:/,$editor);
	    if ($editor_role eq $role
		&& defined($editor_sec)
		&& defined($section)
		&& $editor_sec eq $section) {
		$can_edit = 1;
		last;
	    }
	    if ($editor_role eq $role
		&& !defined($editor_sec)) {
		$can_edit = 1;
	    }
	}
    }
    return $can_edit;
}

sub check_group_priv {
    my ($group,$grp_priv) = @_;
    foreach my $priv ('mdg','vcg') {
        my $checkcourse = $env{'request.course.id'}.
            ($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:'');
        if (&Apache::lonnet::allowed($priv,$checkcourse)) {
            return 'ok';
        }
    }
    if ($grp_priv && $group ne '') {
        if (&Apache::lonnet::allowed($grp_priv,$env{'request.course.id'}.'/'.$group)) {
            return 'ok';
        }
    }
    return '';
}

sub group_args { 
    my ($group) = @_;
    if ($group eq '') { return ''; }
    my $extra_args = '&amp;group='.$group;
    if (exists($env{'form.ref'})) {
        $extra_args .= '&amp;ref='.$env{'form.ref'};
    }
    return $extra_args;
}

sub get_resource_title {
    my ($symb,$feedurl) = @_;
    my ($restitle,$plainurl);
    if (defined($symb)) {
        my $plain_symb = &Apache::lonenc::check_decrypt($symb);
        $restitle = &Apache::lonnet::gettitle($plain_symb);
    }
    if (defined($feedurl)) {
        $plainurl = &Apache::lonenc::check_decrypt($feedurl);
    }
    if (!defined($restitle)) {
        if (defined($feedurl)) {
            $restitle = &Apache::lonnet::gettitle($plainurl);
        }
    }
    if ($plainurl ne $feedurl) {
        my ($plain_filename) = ($plainurl =~ m-/([^/]+)$-);
        if ($plain_filename eq $restitle) {
            $restitle = &mt('Untitled resource');
        }
    }
    if ($restitle eq '') {
        $restitle = &mt('Untitled resource');
    }
    return $restitle;
}

1;
__END__


=pod

=head1 NAME

Apache::lonfeedback.pm

=head1 SYNOPSIS

Handles feedback from students to instructors and system administrators.

Provides a screenshot of the current resource, as well as previous attempts if the resource was a homework.

Used by lonmsg.pm.

This is part of the LearningOnline Network with CAPA project
described at http://www.lon-capa.org.

=head1 OVERVIEW

None

=head1 SUBROUTINES

=over

=item discussion_open()

=item discussion_visible()

=item discussion_vote_available()

=item get_realsymb()

=item list_discussion()

=item can_see_hidden()

=item discussion_link()

=item send_feedback_link()

=item send_message_link()

=item action_links_bar()

=item postingform_display()

=item build_posting_display

=item filter_regexp()

=item get_post_contents()

=item replicate_attachments()

=item mail_screen()

=item print_display_options()

=item print_sortfilter_options()

=item print_showposters()

=item get_post_versions()

=item get_post_attachments()

=item fail_redirect()

=item redirect_back()

=item no_redirect_back()

=item screen_header()

=item resource_output()

=item clear_out_html()

=item assemble_email()

=item feedback_available()

=item send_msg()

=item adddiscuss()

=item get_discussion_info()

=item show_preview()

=item newline_to_br()

=item tidy_html()

=item generate_preview_button()

=item modify_attachments()

=item process_attachments()

=item generate_attachments_button()

=item extract_attachments()

=item construct_attachmenturl()

=item add_blog_checkbox()

=item has_discussion()

=item sort_filter_names()

=item handler()

=item blocked_reply_or_edit()

=item wrap_symb()

=item dewrapper()

=item get_feedurl()

=item get_feedurl_and_clean_symb()

=item editing_allowed()

=item check_group_priv()

=item group_args()

=item get_resource_title()

=back

=cut