# The LearningOnline Network
# Feedback
#
# $Id: lonfeedback.pm,v 1.73.2.1 2004/02/18 20:33:49 albertel Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# LON-CAPA is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#
###

package Apache::lonfeedback;

use strict;
use Apache::Constants qw(:common);
use Apache::lonmsg();
use Apache::loncommon();
use Apache::lontexconvert();
use Apache::lonlocal;

sub list_discussion {
    my ($mode,$status,$symb)=@_;
    my $discussiononly=0;
    if ($mode eq 'board') { $discussiononly=1; }
    unless ($ENV{'request.course.id'}) { return ''; }
    my $crs='/'.$ENV{'request.course.id'};
    if ($ENV{'request.course.sec'}) {
	$crs.='_'.$ENV{'request.course.sec'};
    }                 
    $crs=~s/\_/\//g;
    unless ($symb) {
	$symb=&Apache::lonnet::symbread();
    }
    unless ($symb) { return ''; }
    my $seeid=&Apache::lonnet::allowed('rin',$crs);
    my $viewgrades=(&Apache::lonnet::allowed('vgr',$crs)
	&& ($symb=~/\.(problem|exam|quiz|assess|survey|form)$/));
    my @discussionitems=();
    # backward compatability (bulltein boards used to be 'wrapped')
    my $ressymb=$symb;
    if ($mode eq 'board') {
	$ressymb=~s|(bulletin___\d+___)|$1adm/wrapper|;
    }
    my %contrib=&Apache::lonnet::restore($ressymb,$ENV{'request.course.id'},
			  $ENV{'course.'.$ENV{'request.course.id'}.'.domain'},
			  $ENV{'course.'.$ENV{'request.course.id'}.'.num'});
    my $visible=0;
    my @depth=();
    my @original=();
    my @index=();
    my @replies=();
    my %alldiscussion=();
    my $maxdepth=0;

    my $target='';
    unless ($ENV{'browser.interface'} eq 'textual' ||
	    $ENV{'environment.remote'} eq 'off' ) {
	$target='target="LONcom"';
    }
    if ($contrib{'version'}) {
	for (my $id=1;$id<=$contrib{'version'};$id++) {
	    my $idx=$id;
	    my $hidden=($contrib{'hidden'}=~/\.$idx\./);
	    my $deleted=($contrib{'deleted'}=~/\.$idx\./);
	    my $origindex='0.';
	    if (($contrib{$idx.':replyto'}) && ($ENV{'environment.threadeddiscussion'})) {
# 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 {
# this is an original message
		$original[$idx]=0;
		$depth[$idx]=0;
	    }
	    if ($replies[$depth[$idx]]) {
		$replies[$depth[$idx]]++;
	    } else {
		$replies[$depth[$idx]]=1;
	    }
	    unless ((($hidden) && (!$seeid)) || ($deleted)) {
		$visible++;
		my $message=$contrib{$idx.':message'};
		$message=~s/\n/\<br \/\>/g;
		$message=&Apache::lontexconvert::msgtexconverted($message);
		if ($contrib{$idx.':attachmenturl'}) {
		    my ($fname,$ft)
                        =($contrib{$idx.':attachmenturl'}=~/\/(\w+)\.(\w+)$/);
		    $message.='<p>'.&mt('Attachment').': <a href="'.
			&Apache::lonnet::tokenwrapper(
                                             $contrib{$idx.':attachmenturl'}).
			'"><tt>'.$fname.'.'.$ft.'</tt></a></p>';
		}
		if ($message) {
		    if ($hidden) {
			$message='<font color="#888888">'.$message.'</font>';
		    }
		    my $screenname=&Apache::loncommon::screenname(
					    $contrib{$idx.':sendername'},
					    $contrib{$idx.':senderdomain'});
		    my $plainname=&Apache::loncommon::nickname(
					    $contrib{$idx.':sendername'},
					    $contrib{$idx.':senderdomain'});
		    
		    my $sender=&mt('Anonymous');
		    if ((!$contrib{$idx.':anonymous'}) || ($seeid)) {
			$sender=&Apache::loncommon::aboutmewrapper(
					 $plainname,
					 $contrib{$idx.':sendername'},
					 $contrib{$idx.':senderdomain'}).' ('.
					 $contrib{$idx.':sendername'}.' at '.
					 $contrib{$idx.':senderdomain'}.')';
			if ($contrib{$idx.':anonymous'}) {
			    $sender.=' ['.&mt('anonymous').'] '.
				$screenname;
			}
			if ($seeid) {
			    if ($hidden) {
				$sender.=' <a href="/adm/feedback?unhide='.
				    $ressymb.':::'.$idx.'">'.&mt('Make Visible').'</a>';
			    } else {
				$sender.=' <a href="/adm/feedback?hide='.
				    $ressymb.':::'.$idx.'">'.&mt('Hide').'</a>';
			    }                     
			    $sender.=' <a href="/adm/feedback?deldisc='.
				$ressymb.':::'.$idx.'">'.&mt('Delete').'</a>';
			}
		    } else {
			if ($screenname) {
			    $sender='<i>'.$screenname.'</i>';
			}
		    }
		    if (&Apache::lonnet::allowed('pch',
						 $ENV{'request.course.id'}.
						 ($ENV{'request.course.sec'}?'/'.$ENV{'request.course.sec'}:''))) {
			$sender.=' <a href="/adm/feedback?replydisc='.
			    $ressymb.':::'.$idx.'" '.$target.'>'.&mt('Reply').'</a>';
		    }
		    my $vgrlink;
		    if ($viewgrades) {
			$vgrlink=&Apache::loncommon::submlink('Submissions',
            $contrib{$idx.':sendername'},$contrib{$idx.':senderdomain'},$symb);
		    }
#figure out at what position this needs to print
		    my $thisindex=$idx;
		    if ($ENV{'environment.threadeddiscussion'}) {
			$thisindex=$origindex.substr('00'.$replies[$depth[$idx]],-2,2);	
		    }
		    $alldiscussion{$thisindex}=$idx;
		    $index[$idx]=$thisindex;
		    $discussionitems[$idx]='<p><b>'.$sender.'</b> '.$vgrlink.' ('.
			localtime($contrib{$idx.':timestamp'}).
			'):<blockquote>'.$message.
			'</blockquote></p>';
	        }
	    } 
	}
    }
    my $discussion='';
    if ($visible) {
# Print a the discusssion
	$discussion.='<table bgcolor="#AAAAAA" cellpadding="2" cellspacing="2" border="0">';
	if ($visible>2) {
	    my $colspan=$maxdepth+1;
	    $discussion.='<tr><td bgcolor="DDDDBB" colspan="'.$colspan.'">'.
  '<a href="/adm/feedback?threadedon='.$symb.'">'.&mt('Threaded View').'</a>&nbsp;&nbsp;'.
  '<a href="/adm/feedback?threadedoff='.$symb.'">'.&mt('Chronological View').'</a>'.
  '</td></tr>';
	}

	foreach (sort { $a <=> $b } keys %alldiscussion) {
	    $discussion.="\n<tr>";
	    my $thisdepth=$depth[$alldiscussion{$_}];
	    for (1..$thisdepth) {
		$discussion.='<td>&nbsp;&nbsp;&nbsp;</td>';
	    }
	    my $colspan=$maxdepth-$thisdepth+1;
            $discussion.="<td  bgcolor='#CCCCCC' colspan='".$colspan."'>".$discussionitems[$alldiscussion{$_}].
		"</td></tr>";
	}
        $discussion.='</table>';
    }
    if ($discussiononly) {
	$discussion.=(<<ENDDISCUSS);
<form action="/adm/feedback" method="post" name="mailform" enctype="multipart/form-data">
<input type="submit" name="discuss" value="Post Discussion" />
<input type="submit" name="anondiscuss" value="Post Anonymous Discussion" />
<input type="hidden" name="symb" value="$ressymb" />
<input type="hidden" name="sendit" value="true" />
<br />
<font size="1">Note: in anonymous discussion, your name is visible only to
course faculty</font><br />
<textarea name="comment" cols="60" rows="10" wrap="hard"></textarea>
<p>
Attachment (128 KB max size): <input type="file" name="attachment" />
</p>
</form>
ENDDISCUSS
      $discussion.=&generate_preview_button();
   }
   return $discussion;
}

sub mail_screen {
  my ($r,$feedurl,$options) = @_;
  my $bodytag=&Apache::loncommon::bodytag('Resource Feedback and Discussion',
                                          '','onLoad="window.focus();"');
  my $title=&Apache::lonnet::gettitle($feedurl);
  if (!$title) { $title = $feedurl; }
  my $quote='';
  if ($ENV{'form.replydisc'}) {
      my ($symb,$idx)=split(/\:\:\:/,$ENV{'form.replydisc'});
      my %contrib=&Apache::lonnet::restore($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 $message=$contrib{$idx.':message'};
	  $message=~s/\n/\<br \/\>/g;
	  $quote='<blockquote>'.&Apache::lontexconvert::msgtexconverted($message).'</blockquote>';
      }
  }
  my $latexHelp = Apache::loncommon::helpLatexCheatsheet();
  $r->print(<<ENDDOCUMENT);
<html>
<head>
<title>The LearningOnline Network with CAPA</title>
<meta http-equiv="pragma" content="no-cache"></meta>
<script type="text/javascript">
//<!--
    function gosubmit() {
        var rec=0;
        if (typeof(document.mailform.elements.author)!="undefined") {
          if (document.mailform.elements.author.checked) {
             rec=1;
          } 
        }
        if (typeof(document.mailform.elements.question)!="undefined") {
          if (document.mailform.elements.question.checked) {
             rec=1;
          } 
        }
        if (typeof(document.mailform.elements.course)!="undefined") {
          if (document.mailform.elements.course.checked) {
             rec=1;
          } 
        }
        if (typeof(document.mailform.elements.policy)!="undefined") {
          if (document.mailform.elements.policy.checked) {
             rec=1;
          } 
        }
        if (typeof(document.mailform.elements.discuss)!="undefined") {
          if (document.mailform.elements.discuss.checked) {
             rec=1;
          } 
        }
        if (typeof(document.mailform.elements.anondiscuss)!="undefined") {
          if (document.mailform.elements.anondiscuss.checked) {
             rec=1;
          } 
        }

        if (rec) {
	    document.mailform.submit();
        } else {
            alert('Please check a feedback type.');
	}
    }
//-->
</script>
</head>
$bodytag
<h2><tt>$title</tt></h2>
<form action="/adm/feedback" method="post" name="mailform"
enctype="multipart/form-data">
<input type="hidden" name="postdata" value="$feedurl" />
<input type="hidden" name="replydisc" value="$ENV{'form.replydisc'}" />
Please check at least one of the following feedback types:
$options<hr />
$quote
<p>My question/comment/feedback:</p>
<p>
$latexHelp
<textarea name="comment" cols="60" rows="10" wrap="hard">
</textarea></p>
<p>
Attachment (128 KB max size): <input type="file" name="attachment" />
</p>
<p>
<input type="hidden" name="sendit" value="1" />
<input type="button" value="Send Feedback" onClick='gosubmit();' />
</p>
</form>
ENDDOCUMENT
$r->print(&generate_preview_button().'</body></html>');
}

sub fail_redirect {
  my ($r,$feedurl) = @_;
  if ($feedurl=~/^\/adm\//) { $feedurl.='?register=1' };
  $r->print (<<ENDFAILREDIR);
<html>
<head><title>Feedback not sent</title>
<meta http-equiv="pragma" content="no-cache" />
<meta HTTP-EQUIV="Refresh" CONTENT="2; url=$feedurl" />
</head>
<body bgcolor="#FFFFFF">
<img align="right" src="/adm/lonIcons/lonlogos.gif" />
<b>Sorry, no recipients  ...</b>
</body>
</html>
ENDFAILREDIR
}

sub redirect_back {
  my ($r,$feedurl,$typestyle,$sendsomething,$sendposts,$status) = @_;
  if ($feedurl=~/^\/adm\//) { $feedurl.='?register=1' };
  $r->print (<<ENDREDIR);
<html>
<head>
<title>Feedback sent</title>
<meta http-equiv="pragma" content="no-cache" />
<meta HTTP-EQUIV="Refresh" CONTENT="2; url=$feedurl">
</head>
<body bgcolor="#FFFFFF" onLoad='if (window.name!="loncapaclient") { this.document.reldt.submit(); self.close(); }'>
<img align="right" src="/adm/lonIcons/lonlogos.gif" />
$typestyle
<b>Sent $sendsomething message(s), and $sendposts post(s).</b>
<font color="red">$status</font>
<form name="reldt" action="$feedurl" target="loncapaclient">
</form>
</body>
</html>
ENDREDIR
}

sub no_redirect_back {
  my ($r,$feedurl) = @_;
  $r->print (<<ENDNOREDIR);
<html>
<head><title>Feedback not sent</title>
<meta http-equiv="pragma" content="no-cache" />
ENDNOREDIR

  if ($feedurl!~/^\/adm\/feedback/) { 
    $r->print('<meta HTTP-EQUIV="Refresh" CONTENT="2; url='.$feedurl.'">');
  }
  
  $r->print (<<ENDNOREDIRTWO);
</head>
<body bgcolor="#FFFFFF" onLoad='if (window.name!="loncapaclient") { self.close(); }'>
<img align="right" src="/adm/lonIcons/lonlogos.gif" />
<b>Sorry, no feedback possible on this resource  ...</b>
</body>
</html>
ENDNOREDIRTWO
}

sub screen_header {
    my ($feedurl) = @_;
    my $msgoptions='';
    my $discussoptions='';
    unless ($ENV{'form.replydisc'}) {
	if (($feedurl=~/^\/res\//) && ($feedurl!~/^\/res\/adm/)) {
	    $msgoptions= 
		'<p><input type="checkbox" name="author" /> '.
		&mt('Feedback to resource author').'</p>';
	}
	if (&feedback_available(1)) {
	    $msgoptions.=
		'<br /><input type="checkbox" name="question" /> '.
		&mt('Question about resource content');
	}
	if (&feedback_available(0,1)) {
	    $msgoptions.=
		'<br /><input type="checkbox" name="course" /> '.
		&mt('Question/Comment/Feedback about course content');
	}
	if (&feedback_available(0,0,1)) {
	    $msgoptions.=
		'<br /><input type="checkbox" name="policy" /> '.
		&mt('Question/Comment/Feedback about course policy');
	}
    }
    if ($ENV{'request.course.id'}) {
	if (&Apache::lonnet::allowed('pch',
				     $ENV{'request.course.id'}.
				     ($ENV{'request.course.sec'}?'/'.$ENV{'request.course.sec'}:''))) {
	    $discussoptions='<input type="checkbox" name="discuss" onClick="this.form.anondiscuss.checked=false;" /> '.
		&mt('Contribution to course discussion of resource');
	    $discussoptions.='<br /><input type="checkbox" name="anondiscuss" onClick="this.form.discuss.checked=false;" /> '.
		&mt('Anonymous contribution to course discussion of resource').
		' <i>('.&mt('name only visible to course faculty').')</i>';
      }
    }
    if ($msgoptions) { $msgoptions='<h2>'.&mt('Sending Messages').'</h2>'.$msgoptions; }
    if ($discussoptions) { 
	$discussoptions='<h2>'.&mt('Discussion Contributions').'</h2>'.$discussoptions; }
    return $msgoptions.$discussoptions;
}

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)=@_;
  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>
      my %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, DIV=>1, IMG=>1,
                M=>1);

      $message =~ s/\<(\/?\s*(\w+)[^\>\<]*)/
	  {($html{uc($2)}&&(length($1)<1000))?"\<$1":"\&lt;$1"}/ge;
      $message =~ s/(\<?\s*(\w+)[^\<\>]*)\>/
	  {($html{uc($2)}&&(length($1)<1000))?"$1\>":"$1\&gt;"}/ge;
  } else {
      $message=~s/\</\&lt\;/g;
      $message=~s/\>/\&gt\;/g;
  }
  return $message;
}

sub assemble_email {
  my ($feedurl,$message,$prevattempts,$usersaw,$useranswer)=@_;
  my $email=<<"ENDEMAIL";
Refers to <a href="$feedurl">$feedurl</a>

$message
ENDEMAIL
    my $citations=<<"ENDCITE";
<h2>Previous attempts of student (if applicable)</h2>
$prevattempts
<br /><hr />
<h2>Original screen output (if applicable)</h2>
$usersaw
<h2>Correct Answer(s) (if applicable)</h2>
$useranswer
ENDCITE
  return ($email,$citations);
}

sub secapply {
    my $rec=shift;
    my $defaultflag=shift;
    $rec=~s/\s+//g;
    $rec=~s/\@/\:/g;
    my ($adr,$sections)=($rec=~/^([^\(]+)\(([^\)]+)\)/);
    if ($sections) {
	foreach (split(/\;/,$sections)) {
            if (($_ eq $ENV{'request.course.sec'}) ||
                ($defaultflag && ($_ eq '*'))) {
                return $adr; 
            }
        }
    } else {
       return $rec;
    }
    return '';
}

sub decide_receiver {
  my ($feedurl,$author,$question,$course,$policy,$defaultflag) = @_;
  my $typestyle='';
  my %to=();
  if ($ENV{'form.author'}||$author) {
    $typestyle.='Submitting as Author Feedback<br>';
    $feedurl=~/^\/res\/(\w+)\/(\w+)\//;
    $to{$2.':'.$1}=1;
  }
  if ($ENV{'form.question'}||$question) {
    $typestyle.='Submitting as Question<br>';
    foreach (split(/\,/,
		   $ENV{'course.'.$ENV{'request.course.id'}.'.question.email'})
	     ) {
	my $rec=&secapply($_,$defaultflag);
        if ($rec) { $to{$rec}=1; }
    } 
  }
  if ($ENV{'form.course'}||$course) {
    $typestyle.='Submitting as Comment<br />';
    foreach (split(/\,/,
		   $ENV{'course.'.$ENV{'request.course.id'}.'.comment.email'})
	     ) {
	my $rec=&secapply($_,$defaultflag);
        if ($rec) { $to{$rec}=1; }
    } 
  }
  if ($ENV{'form.policy'}||$policy) {
    $typestyle.='Submitting as Policy Feedback<br />';
    foreach (split(/\,/,
		   $ENV{'course.'.$ENV{'request.course.id'}.'.policy.email'})
	     ) {
	my $rec=&secapply($_,$defaultflag);
        if ($rec) { $to{$rec}=1; }
    } 
  }
  if ((scalar(%to) eq '0') && (!$defaultflag)) {
     ($typestyle,%to)=
	 &decide_receiver($feedurl,$author,$question,$course,$policy,1);
  }
  return ($typestyle,%to);
}

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

sub send_msg {
  my ($feedurl,$email,$citations,$attachmenturl,%to)=@_;
  my $status='';
  my $sendsomething=0;
  foreach (keys %to) {
    if ($_) {
      my $declutter=&Apache::lonnet::declutter($feedurl);
      unless (&Apache::lonmsg::user_normal_msg(split(/\:/,$_),
               'Feedback ['.$declutter.']',$email,$citations,$feedurl,
                $attachmenturl)=~/ok/) {
	$status.='<br />'.&mt('Error sending message to').' '.$_.'<br />';
      } else {
	$sendsomething++;
      }
    }
  }

    my %record=&Apache::lonnet::restore('_feedback');
    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);
}

sub adddiscuss {
    my ($symb,$email,$anon,$attachmenturl)=@_;
    my $status='';
    if (&Apache::lonnet::allowed('pch',$ENV{'request.course.id'}.
        ($ENV{'request.course.sec'}?'/'.$ENV{'request.course.sec'}:''))) {

    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'=> $attachmenturl);
    if ($ENV{'form.replydisc'}) {
	$contrib{'replyto'}=(split(/\:\:\:/,$ENV{'form.replydisc'}))[1];
    }
    if ($anon) {
	$contrib{'anonymous'}='true';
    }
    if (($symb) && ($email)) {
       $status='Adding to class discussion'.($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 => time);
        $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=&Apache::lonnet::restore('_discussion');
    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');
    }
    } else {
	$status.='Failed.';
    }
    return $status.'<br />';   
}

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

sub show_preview {
    my $r=shift;
    my $message=&clear_out_html($ENV{'form.comment'});
    $message=~s/\n/\<br \/\>/g;
    $message=&Apache::lontexconvert::msgtexconverted($message);
    $r->print('<table border="2"><tr><td>'.
       $message.'</td></tr></table>');
}

sub generate_preview_button {
    my $pre=&mt("Show Preview");
    return(<<ENDPREVIEW);
<form name="preview" action="/adm/feedback?preview=1" method="post" target="preview">
<input type="hidden" name="comment" />
<input type="button" value="$pre"
onClick="this.form.comment.value=document.mailform.comment.value;this.form.submit();" />
</form>
ENDPREVIEW
}

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'},
         ['hide','unhide','deldisc','postdata','preview','replydisc','threadedon','threadedoff']);

  if (($ENV{'form.hide'}) || ($ENV{'form.unhide'})) {
# ----------------------------------------------------------------- Hide/unhide
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;

    my $entry=$ENV{'form.hide'}?$ENV{'form.hide'}:$ENV{'form.unhide'};

    my ($symb,$idx)=split(/\:\:\:/,$entry);
    my ($map,$ind,$url)=&Apache::lonnet::decode_symb($symb);

    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 $currenthidden=$contrib{'hidden'};
    
    if ($ENV{'form.hide'}) {
	$currenthidden.='.'.$idx.'.';
    } else {
        $currenthidden=~s/\.$idx\.//g;
    }
    my %newhash=('hidden' => $currenthidden);

    &Apache::lonnet::store(\%newhash,$symb,$ENV{'request.course.id'},
                     $ENV{'course.'.$ENV{'request.course.id'}.'.domain'},
		     $ENV{'course.'.$ENV{'request.course.id'}.'.num'});

    &redirect_back($r,&Apache::lonnet::clutter($url),
       &mt('Changed discussion status').'<br />','0','0');
  } elsif (($ENV{'form.threadedon'}) || ($ENV{'form.threadedoff'})) {
      &Apache::loncommon::content_type($r,'text/html');
      $r->send_http_header;
      if ($ENV{'form.threadedon'}) {
	  &Apache::lonnet::put('environment',{'threadeddiscussion' => 'on'});
	  &Apache::lonnet::appenv('environment.threadeddiscussion' => 'on');
      } else {
 	  &Apache::lonnet::del('environment',['threadeddiscussion']);
	  &Apache::lonnet::delenv('environment\.threadeddiscussion');
      }
      my $symb=$ENV{'form.threadedon'}?$ENV{'form.threadedon'}:$ENV{'form.threadedoff'};
      my ($map,$ind,$url)=&Apache::lonnet::decode_symb($symb);
      &redirect_back($r,&Apache::lonnet::clutter($url),
		     &mt('Changed discussion view mode').'<br />','0','0');
  } elsif ($ENV{'form.deldisc'}) {
# --------------------------------------------------------------- Hide for good
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;

    my $entry=$ENV{'form.deldisc'};

    my ($symb,$idx)=split(/\:\:\:/,$entry);
    my ($map,$ind,$url)=&Apache::lonnet::decode_symb($symb);

    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 $currentdeleted=$contrib{'deleted'};
    
    $currentdeleted.='.'.$idx.'.';

    my %newhash=('deleted' => $currentdeleted);

    &Apache::lonnet::store(\%newhash,$symb,$ENV{'request.course.id'},
                     $ENV{'course.'.$ENV{'request.course.id'}.'.domain'},
		     $ENV{'course.'.$ENV{'request.course.id'}.'.num'});

    &redirect_back($r,&Apache::lonnet::clutter($url),
       &mt('Changed discussion status').'<br />','0','0');
  } elsif ($ENV{'form.preview'}) {
# -------------------------------------------------------- User wants a preview
      $r->content_type('text/html');
      $r->send_http_header;
      &show_preview($r);
  } else {
# ------------------------------------------------------------- Normal feedback
  my $feedurl=$ENV{'form.postdata'};
  $feedurl=~s/^http\:\/\///;
  $feedurl=~s/^$ENV{'SERVER_NAME'}//;
  $feedurl=~s/^$ENV{'HTTP_HOST'}//;
  $feedurl=~s/\?.+$//;

  my $symb;
  if ($ENV{'form.replydisc'}) {
      $symb=(split(/\:\:\:/,$ENV{'form.replydisc'}))[0];
      my ($map,$id,$url)=&Apache::lonnet::decode_symb($symb);
      $feedurl=&Apache::lonnet::clutter($url);
  } else {
      $symb=&Apache::lonnet::symbread($feedurl);
  }
  unless ($symb) {
      $symb=$ENV{'form.symb'};
      if ($symb) {
	  my ($map,$id,$url)=&Apache::lonnet::decode_symb($symb);
          $feedurl=&Apache::lonnet::clutter($url);
      }
  }
  my $goahead=1;
  if ($feedurl=~/\.(problem|exam|quiz|assess|survey|form)$/) {
      unless ($symb) { $goahead=0; }
  }
  # backward compatability (bulltein boards used to be 'wrapped')
  if ($feedurl=~m|^/adm/wrapper/adm/.*/bulletinboard$|) {
      $feedurl=~s|^/adm/wrapper||;
  }
  if ($goahead) {
# Go ahead with feedback, no ambiguous reference
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
  
    if (
      (
       ($feedurl=~m:^/res:) && ($feedurl!~m:^/res/adm:)
      ) 
      || 
      ($ENV{'request.course.id'} && ($feedurl!~m:^/adm:))
      ||
      ($ENV{'request.course.id'} && ($symb=~/^bulletin\_\_\_/))
     ) {
# --------------------------------------------------- Print login screen header
    unless ($ENV{'form.sendit'}) {
      my $options=&screen_header($feedurl);
      if ($options) {
	&mail_screen($r,$feedurl,$options);
      } else {
	&fail_redirect($r,$feedurl);
      }
    } else {
      
# 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
      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 $useranswer=&Apache::loncommon::get_student_answers(
                       $symb,$ENV{'user.name'},$ENV{'user.domain'},
		       $ENV{'request.course.id'});
      &Apache::lonnet::delenv('allowed.vgr');
# Get attachments, if any, and not too large
      my $attachmenturl='';
      if ($ENV{'form.attachment.filename'}) {
	  unless (length($ENV{'form.attachment'})>131072) {
	      $attachmenturl=&Apache::lonnet::userfileupload('attachment');
	  }
      }
# Filter HTML out of message (could be nasty)
      my $message=&clear_out_html($ENV{'form.comment'});

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

# Actually send mail
      my ($status,$numsent)=&send_msg($feedurl,$email,$citations,
          $attachmenturl,%to);

# Discussion? Store that.

      my $numpost=0;
      if ($ENV{'form.discuss'}) {
	  $typestyle.=&adddiscuss($symb,$message,0,$attachmenturl);
	  $numpost++;
      }

      if ($ENV{'form.anondiscuss'}) {
	  $typestyle.=&adddiscuss($symb,$message,1,$attachmenturl);
	  $numpost++;
      }


# Receipt screen and redirect back to where came from
      &redirect_back($r,$feedurl,$typestyle,$numsent,$numpost,$status);

    }
   } else {
# Unable to give feedback
    &no_redirect_back($r,$feedurl);
   }
  } else {
# Ambiguous Problem Resource
      if ( &Apache::lonnet::mod_perl_version() == 2 ) {
	  &Apache::lonnet::cleanenv();
      }
      $r->internal_redirect('/adm/ambiguous');
  }
}
  return OK;
} 

1;
__END__