# The LearningOnline Network with CAPA
# Routines for messaging
#
# $Id: lonmsg.pm,v 1.189 2006/12/06 23:44:33 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::lonmsg;

use strict;
use Apache::lonnet;
use HTML::TokeParser();
use Apache::lonlocal;
use Mail::Send;
use LONCAPA qw(:DEFAULT :match);

{
    my $uniq;
    sub get_uniq {
	$uniq++;
	return $uniq;
    }
}

# ===================================================================== Package

sub packagemsg {
    my ($subject,$message,$citation,$baseurl,$attachmenturl,
	$recuser,$recdomain,$msgid,$type,$crsmsgid)=@_;
    $message =&HTML::Entities::encode($message,'<>&"');
    $citation=&HTML::Entities::encode($citation,'<>&"');
    $subject =&HTML::Entities::encode($subject,'<>&"');
    #remove machine specification
    $baseurl =~ s|^http://[^/]+/|/|;
    $baseurl =&HTML::Entities::encode($baseurl,'<>&"');
    #remove machine specification
    $attachmenturl =~ s|^http://[^/]+/|/|;
    $attachmenturl =&HTML::Entities::encode($attachmenturl,'<>&"');
    my $course_context;
    if (defined($env{'form.replyid'})) {
        my ($sendtime,$shortsubj,$fromname,$fromdomain,$count,$origcid)=
                   split(/\:/,&unescape($env{'form.replyid'}));
        $course_context = $origcid;
    }
    foreach my $key (keys(%env)) {
        if ($key=~/^form\.(rep)?rec\_(.*)$/) {
            my ($sendtime,$shortsubj,$fromname,$fromdomain,$count,$origcid) =
                                    split(/\:/,&unescape($2));
            $course_context = $origcid;
            last;
        }
    }
    unless(defined($course_context)) {
        $course_context = $env{'request.course.id'};
    }
    my $now=time;
    my $msgcount = &get_uniq();
    unless(defined($msgid)) {
        $msgid = &buildmsgid($now,$subject,$env{'user.name'},$env{'user.domain'},
                            $msgcount,$course_context,$$);
    }
    my $result = '<sendername>'.$env{'user.name'}.'</sendername>'.
           '<senderdomain>'.$env{'user.domain'}.'</senderdomain>'.
           '<subject>'.$subject.'</subject>'.
           '<time>'.&Apache::lonlocal::locallocaltime($now).'</time>';
    if (defined($crsmsgid)) {
        $result.= '<courseid>'.$course_context.'</courseid>'.
                  '<coursesec>'.$env{'request.course.sec'}.'</coursesec>'.
                  '<msgid>'.$msgid.'</msgid>'.
                  '<coursemsgid>'.$crsmsgid.'</coursemsgid>'.
                  '<message>'.$message.'</message>';
        return ($msgid,$result);
    }
    $result .= '<servername>'.$ENV{'SERVER_NAME'}.'</servername>'.
           '<host>'.$ENV{'HTTP_HOST'}.'</host>'.
	   '<client>'.$ENV{'REMOTE_ADDR'}.'</client>'.
	   '<browsertype>'.$env{'browser.type'}.'</browsertype>'.
	   '<browseros>'.$env{'browser.os'}.'</browseros>'.
	   '<browserversion>'.$env{'browser.version'}.'</browserversion>'.
           '<browsermathml>'.$env{'browser.mathml'}.'</browsermathml>'.
	   '<browserraw>'.$ENV{'HTTP_USER_AGENT'}.'</browserraw>'.
	   '<courseid>'.$course_context.'</courseid>'.
	   '<coursesec>'.$env{'request.course.sec'}.'</coursesec>'.
	   '<role>'.$env{'request.role'}.'</role>'.
	   '<resource>'.$env{'request.filename'}.'</resource>'.
           '<msgid>'.$msgid.'</msgid>';
    if (ref($recuser) eq 'ARRAY') {
        for (my $i=0; $i<@{$recuser}; $i++) {
            if ($type eq 'dcmail') {
                my ($username,$email) = split(/:/,$$recuser[$i]);
                $username = &unescape($username);
                $email = &unescape($email);
                $username = &HTML::Entities::encode($username,'<>&"');
                $email = &HTML::Entities::encode($email,'<>&"');
                $result .= '<recipient username="'.$username.'">'.
                                            $email.'</recipient>';
            } else {
                $result .= '<recuser>'.$$recuser[$i].'</recuser>'.
                           '<recdomain>'.$$recdomain[$i].'</recdomain>';
            }
        }
    } else {
        $result .= '<recuser>'.$recuser.'</recuser>'.
                   '<recdomain>'.$recdomain.'</recdomain>';
    }
    $result .= '<message>'.$message.'</message>';
    if (defined($citation)) {
	$result.='<citation>'.$citation.'</citation>';
    }
    if (defined($baseurl)) {
	$result.= '<baseurl>'.$baseurl.'</baseurl>';
    }
    if (defined($attachmenturl)) {
	$result.= '<attachmenturl>'.$attachmenturl.'</attachmenturl>';
    }
    return $msgid,$result;
}

# ================================================== Unpack message into a hash

sub unpackagemsg {
    my ($message,$notoken)=@_;
    my %content=();
    my $parser=HTML::TokeParser->new(\$message);
    my $token;
    while ($token=$parser->get_token) {
       if ($token->[0] eq 'S') {
	   my $entry=$token->[1];
           my $value=$parser->get_text('/'.$entry);
           if (($entry eq 'recuser') || ($entry eq 'recdomain')) {
               push(@{$content{$entry}},$value);
           } elsif ($entry eq 'recipient') {
               my $username = $token->[2]{'username'};
               $username = &HTML::Entities::decode($username,'<>&"');
               $content{$entry}{$username} = $value;
           } else {
               $content{$entry}=$value;
           }
       }
    }
    if (!exists($content{'recuser'})) { $content{'recuser'} = []; }
    if ($content{'attachmenturl'}) {
       my ($fname)=($content{'attachmenturl'}=~m|/([^/]+)$|);
       if ($notoken) {
	   $content{'message'}.='<p>'.&mt('Attachment').': <tt>'.$fname.'</tt>';
       } else {
	   &Apache::lonnet::allowuploaded('/adm/msg',
					  $content{'attachmenturl'});
	   $content{'message'}.='<p>'.&mt('Attachment').
	       ': <a href="'.$content{'attachmenturl'}.'"><tt>'.
	       $fname.'</tt></a>';
       }
    }
    return %content;
}

# ======================================================= Get info out of msgid

sub buildmsgid {
    my ($now,$subject,$uname,$udom,$msgcount,$course_context,$pid) = @_;
    $subject=&escape($subject);
    return(&escape($now.':'.$subject.':'.$uname.':'.
           $udom.':'.$msgcount.':'.$course_context.':'.$pid));
}

sub unpackmsgid {
    my ($msgid,$folder,$skipstatus,$status_cache)=@_;
    $msgid=&unescape($msgid);
    my ($sendtime,$shortsubj,$fromname,$fromdomain,$count,$fromcid,
                     $processid)=split(/\:/,&unescape($msgid));
    $shortsubj = &unescape($shortsubj);
    $shortsubj = &HTML::Entities::decode($shortsubj);
    if (!defined($processid)) { $fromcid = ''; }
    my %status=();
    unless ($skipstatus) {
	if (ref($status_cache)) {
	    $status{$msgid} = $status_cache->{$msgid};
	} else {
	    my $suffix=&foldersuffix($folder);
	    %status=&Apache::lonnet::get('email_status'.$suffix,[$msgid]);
	}
	if ($status{$msgid}=~/^error\:/) { $status{$msgid}=''; }
        unless ($status{$msgid}) { $status{$msgid}='new'; }
    }
    return ($sendtime,$shortsubj,$fromname,$fromdomain,$status{$msgid},$fromcid);
}


sub sendemail {
    my ($to,$subject,$body)=@_;
    my %senderemails=&Apache::loncommon::getemails();
    my $senderaddress='';
    foreach my $type ('notification','permanentemail','critnotification') {
	if ($senderemails{$type}) {
	    $senderaddress=$senderemails{$type};
	}
    }
    $body=
    "*** ".&mt('This is an automatic message generated by the LON-CAPA system.')."\n".
    "*** ".($senderaddress?&mt('You can reply to this message'):&mt('Please do not reply to this address.')."\n*** ".
	    &mt('A reply will not be received by the recipient!'))."\n\n".$body;
    my $msg = new Mail::Send;
    $msg->to($to);
    $msg->subject('[LON-CAPA] '.$subject);
    if ($senderaddress) { $msg->add('Reply-to',$senderaddress); $msg->add('From',$senderaddress); }
    if (my $fh = $msg->open()) {
	print $fh $body;
	$fh->close;
    }
}

# ==================================================== Send notification emails

sub sendnotification {
    my ($to,$touname,$toudom,$subj,$crit,$text)=@_;
    my $sender=$env{'environment.firstname'}.' '.$env{'environment.lastname'};
    unless ($sender=~/\w/) { 
	$sender=$env{'user.name'}.'@'.$env{'user.domain'};
    }
    my $critical=($crit?' critical':'');
    $text=~s/\&lt\;/\</gs;
    $text=~s/\&gt\;/\>/gs;
    $text=~s/\<\/*[^\>]+\>//gs;
    my $url='http://'.
      $Apache::lonnet::hostname{&Apache::lonnet::homeserver($touname,$toudom)}.
      '/adm/email?username='.$touname.'&domain='.$toudom;
    my $body=(<<ENDMSG);
You received a$critical message from $sender in LON-CAPA. The subject is

 $subj

=== Excerpt ============================================================
$text
========================================================================

Use

 $url

to access the full message.
ENDMSG
    &sendemail($to,'New'.$critical.' message from '.$sender,$body);
}
# ============================================================= Check for email

sub newmail {
    if ((time-$env{'user.mailcheck.time'})>300) {
        my %what=&Apache::lonnet::get('email_status',['recnewemail']);
        &Apache::lonnet::appenv('user.mailcheck.time'=>time);
        if ($what{'recnewemail'}>0) { return 1; }
    }
    return 0;
}

# =============================== Automated message to the author of a resource

=pod

=item * B<author_res_msg($filename, $message)>: Sends message $message to the owner
    of the resource with the URI $filename.

=cut

sub author_res_msg {
    my ($filename,$message)=@_;
    unless ($message) { return 'empty'; }
    $filename=&Apache::lonnet::declutter($filename);
    my ($domain,$author,@dummy)=split(/\//,$filename);
    my $homeserver=&Apache::lonnet::homeserver($author,$domain);
    if ($homeserver ne 'no_host') {
       my $id=unpack("%32C*",$message);
       $message .= " <p>This error occurred on machine ".
	   $Apache::lonnet::perlvar{'lonHostID'}."</p>";
       my $msgid;
       ($msgid,$message)=&packagemsg($filename,$message);
       return &Apache::lonnet::reply('put:'.$domain.':'.$author.
         ':nohist_res_msgs:'.
          &escape($filename.'_'.$id).'='.
          &escape($message),$homeserver);
    }
    return 'no_host';
}

# =========================================== Retrieve author resource messages

sub retrieve_author_res_msg {
    my $url=shift;
    $url=&Apache::lonnet::declutter($url);
    my ($domain,$author)=($url=~/^($match_domain)\/($match_username)\//);
    my %errormsgs=&Apache::lonnet::dump('nohist_res_msgs',$domain,$author);
    my $msgs='';
    foreach (keys %errormsgs) {
	if ($_=~/^\Q$url\E\_\d+$/) {
	    my %content=&unpackagemsg($errormsgs{$_});
	    $msgs.='<p><img src="/adm/lonMisc/bomb.gif" /><b>'.
		$content{'time'}.'</b>: '.$content{'message'}.
		'<br /></p>';
	}
    } 
    return $msgs;     
}


# =============================== Delete all author messages related to one URL

sub del_url_author_res_msg {
    my $url=shift;
    $url=&Apache::lonnet::declutter($url);
    my ($domain,$author)=($url=~/^($match_domain)\/($match_username)\//);
    my @delmsgs=();
    foreach (&Apache::lonnet::getkeys('nohist_res_msgs',$domain,$author)) {
	if ($_=~/^\Q$url\E\_\d+$/) {
	    push (@delmsgs,$_);
	}
    }
    return &Apache::lonnet::del('nohist_res_msgs',\@delmsgs,$domain,$author);
}
# =================================== Clear out all author messages in URL path

sub clear_author_res_msg {
    my $url=shift;
    $url=&Apache::lonnet::declutter($url);
    my ($domain,$author)=($url=~/^($match_domain)\/($match_username)\//);
    my @delmsgs=();
    foreach (&Apache::lonnet::getkeys('nohist_res_msgs',$domain,$author)) {
	if ($_=~/^\Q$url\E/) {
	    push (@delmsgs,$_);
	}
    }
    return &Apache::lonnet::del('nohist_res_msgs',\@delmsgs,$domain,$author);
}
# ================= Return hash with URLs for which there is a resource message

sub all_url_author_res_msg {
    my ($author,$domain)=@_;
    my %returnhash=();
    foreach (&Apache::lonnet::getkeys('nohist_res_msgs',$domain,$author)) {
	$_=~/^(.+)\_\d+/;
	$returnhash{$1}=1;
    }
    return %returnhash;
}

# ====================================== Add a comment to the User Notes screen

sub store_instructor_comment {
    my ($msg,$uname,$udom) = @_;
    my $cid  = $env{'request.course.id'};
    my $cnum = $env{'course.'.$cid.'.num'};
    my $cdom = $env{'course.'.$cid.'.domain'};
    my $subject= &mt('Record').' ['.$uname.':'.$udom.']';
    my $result = &user_normal_msg_raw($cnum,$cdom,$subject,$msg);
    return $result;
}

# ================================================== Critical message to a user

sub user_crit_msg_raw {
    my ($user,$domain,$subject,$message,$sendback,$toperm,$sentmessage)=@_;
# Check if allowed missing
    my $status='';
    my $msgid='undefined';
    unless (($message)&&($user)&&($domain)) { $status='empty'; };
    my $text=$message;
    my $homeserver=&Apache::lonnet::homeserver($user,$domain);
    if ($homeserver ne 'no_host') {
       ($msgid,$message)=&packagemsg($subject,$message);
       if ($sendback) { $message.='<sendback>true</sendback>'; }
       $status=&Apache::lonnet::critical(
           'put:'.$domain.':'.$user.':critical:'.
           &escape($msgid).'='.
           &escape($message),$homeserver);
        if (defined($sentmessage)) {
            $$sentmessage = $message;
        }
    } else {
       $status='no_host';
    }
# Notifications
    my %userenv = &Apache::loncommon::getemails($user,$domain);
    if ($userenv{'critnotification'}) {
      &sendnotification($userenv{'critnotification'},$user,$domain,$subject,1,
			$text);
    }
    if ($toperm && $userenv{'permanentemail'}) {
      &sendnotification($userenv{'permanentemail'},$user,$domain,$subject,1,
			$text);
    }
# Log this
    &Apache::lonnet::logthis(
      'Sending critical email '.$msgid.
      ', log status: '.
      &Apache::lonnet::log($env{'user.domain'},$env{'user.name'},
                         $env{'user.home'},
      'Sending critical '.$msgid.' to '.$user.' at '.$domain.' with status: '
      .$status));
    return $status;
}

# New routine that respects "forward" and calls old routine

=pod

=item * B<user_crit_msg($user, $domain, $subject, $message, $sendback)>: Sends
    a critical message $message to the $user at $domain. If $sendback is true,
    a reciept will be sent to the current user when $user recieves the message.

    Additionally it will check if the user has a Forwarding address
    set, and send the message to that address instead

    returns 
      - in array context a list of results for each message that was sent
      - in scalar context a space seperated list of results for each 
           message sent

=cut

sub user_crit_msg {
    my ($user,$domain,$subject,$message,$sendback,$toperm,$sentmessage)=@_;
    my @status;
    my %userenv = &Apache::lonnet::get('environment',['msgforward'],
                                       $domain,$user);
    my $msgforward=$userenv{'msgforward'};
    if ($msgforward) {
       foreach my $addr (split(/\,/,$msgforward)) {
	 my ($forwuser,$forwdomain)=split(/\:/,$addr);
         push(@status,
	      &user_crit_msg_raw($forwuser,$forwdomain,$subject,$message,
				 $sendback,$toperm,$sentmessage));
       }
    } else { 
	push(@status,
	     &user_crit_msg_raw($user,$domain,$subject,$message,$sendback,
				$toperm,$sentmessage));
    }
    if (wantarray) {
	return @status;
    }
    return join(' ',@status);
}

# =================================================== Critical message received

sub user_crit_received {
    my $msgid=shift;
    my %message=&Apache::lonnet::get('critical',[$msgid]);
    my %contents=&unpackagemsg($message{$msgid},1);
    my $status='rec: '.($contents{'sendback'}?
     &user_normal_msg($contents{'sendername'},$contents{'senderdomain'},
                     &mt('Receipt').': '.$env{'user.name'}.' '.&mt('at').' '.$env{'user.domain'}.', '.$contents{'subject'},
                     &mt('User').' '.$env{'user.name'}.' '.&mt('at').' '.$env{'user.domain'}.
                     ' acknowledged receipt of message'."\n".'   "'.
                     $contents{'subject'}.'"'."\n".&mt('dated').' '.
                     $contents{'time'}.".\n"
                     ):'no msg req');
    $status.=' trans: '.
     &Apache::lonnet::put(
     'nohist_email',{$contents{'msgid'} => $message{$msgid}});
    $status.=' del: '.
     &Apache::lonnet::del('critical',[$contents{'msgid'}]);
    &Apache::lonnet::log($env{'user.domain'},$env{'user.name'},
                         $env{'user.home'},'Received critical message '.
                         $contents{'msgid'}.
                         ', '.$status);
    return $status;
}

# ======================================================== Normal communication

sub user_normal_msg_raw {
    my ($user,$domain,$subject,$message,$citation,$baseurl,$attachmenturl,
	$toperm,$currid,$newid,$sentmessage,$crsmsgid)=@_;
# Check if allowed missing
    my ($status,$packed_message);
    my $msgid='undefined';
    my $text=$message;
    unless (($message)&&($user)&&($domain)) { $status='empty'; };
    my $homeserver=&Apache::lonnet::homeserver($user,$domain);
    if ($homeserver ne 'no_host') {
       ($msgid,$packed_message)=
	                 &packagemsg($subject,$message,$citation,$baseurl,
                                     $attachmenturl,$user,$domain,$currid,
                                                         undef,$crsmsgid);

# Store in user folder
       $status=&Apache::lonnet::critical(
           'put:'.$domain.':'.$user.':nohist_email:'.
           &escape($msgid).'='.
           &escape($packed_message),$homeserver);
# Save new message received time
       &Apache::lonnet::put
                         ('email_status',{'recnewemail'=>time},$domain,$user);
# Into sent-mail folder unless a broadcast message or critical message
       unless (($env{'request.course.id'}) && 
               (($env{'form.sendmode'} eq 'group')  || 
               (($env{'form.critmsg'}) || ($env{'form.sendbck'})) &&
               (&Apache::lonnet::allowed('srm',$env{'request.course.id'})
		|| &Apache::lonnet::allowed('srm',$env{'request.course.id'}.
					    '/'.$env{'request.course.sec'})))) {
           (undef, my $packed_message_no_citation)=
                             &packagemsg($subject,$message,undef     ,$baseurl,
                                          $attachmenturl,$user,$domain,$currid,
                                                              undef,$crsmsgid);

           $status .= &store_sent_mail($msgid,$packed_message_no_citation);
       }
    } else {
       $status='no_host';
    }
    if (defined($newid)) {
        $$newid = $msgid;
    }
    if (defined($sentmessage)) {
        $$sentmessage = $packed_message;
    }

# Notifications
    my %userenv = &Apache::lonnet::get('environment',['notification',
                                                      'permanentemail'],
                                       $domain,$user);
    if ($userenv{'notification'}) {
	&sendnotification($userenv{'notification'},$user,$domain,$subject,0,
			  $text);
    }
    if ($toperm && $userenv{'permanentemail'}) {
	&sendnotification($userenv{'permanentemail'},$user,$domain,$subject,0,
			  $text);
    }
    &Apache::lonnet::log($env{'user.domain'},$env{'user.name'},
                         $env{'user.home'},
      'Sending '.$msgid.' to '.$user.' at '.$domain.' with status: '.$status);
    return $status;
}

# New routine that respects "forward" and calls old routine

=pod

=item * B<user_normal_msg($user, $domain, $subject, $message,
    $citation, $baseurl, $attachmenturl)>: Sends a message to the
    $user at $domain, with subject $subject and message $message.

=cut

sub user_normal_msg {
    my ($user,$domain,$subject,$message,$citation,$baseurl,$attachmenturl,
	$toperm,$sentmessage)=@_;
    my $status='';
    my %userenv = &Apache::lonnet::get('environment',['msgforward'],
                                       $domain,$user);
    my $msgforward=$userenv{'msgforward'};
    if ($msgforward) {
        foreach (split(/\,/,$msgforward)) {
	    my ($forwuser,$forwdomain)=split(/\:/,$_);
	    $status.=
	        &user_normal_msg_raw($forwuser,$forwdomain,$subject,$message,
				     $citation,$baseurl,$attachmenturl,$toperm,
				     undef,undef,$sentmessage).' ';
        }
    } else { 
	$status=&user_normal_msg_raw($user,$domain,$subject,$message,
				     $citation,$baseurl,$attachmenturl,$toperm,
				     undef,undef,$sentmessage);
    }
    return $status;
}

sub store_sent_mail {
    my ($msgid,$message) = @_;
    my $status =' '.&Apache::lonnet::critical(
               'put:'.$env{'user.domain'}.':'.$env{'user.name'}.
                                          ':nohist_email_sent:'.
               &escape($msgid).'='.
               &escape($message),$env{'user.home'});
    return $status;
}

# =============================================================== Folder suffix

sub foldersuffix {
    my $folder=shift;
    unless ($folder) { return ''; }
    my $suffix;
    my %folderhash = &get_user_folders($folder);
    if (ref($folderhash{$folder}) eq 'HASH') {
        $suffix = '_'.&escape($folderhash{$folder}{'id'});
    } else {
        $suffix = '_'.&escape($folder);
    }
    return $suffix;
}

# ========================================================= User-defined folders 

sub get_user_folders {
    my ($folder) = @_;
    my %userfolders = 
          &Apache::lonnet::dump('email_folders',undef,undef,$folder);
    my $lock = "\0".'lock_counter'; # locks db while counter incremented
    my $counter = "\0".'idcount';   # used in suffix for email db files
    if (defined($userfolders{$lock})) {
        delete($userfolders{$lock});
    }
    if (defined($userfolders{$counter})) {
        delete($userfolders{$counter});
    }
    return %userfolders;
}

1;
__END__