# The LearningOnline Network
# Chat Fetching
#
# $Id: lonchatfetch.pm,v 1.32 2006/11/29 19:45:55 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::lonchatfetch;

use strict;
use Apache::Constants qw(:common :http);
use Apache::lontexconvert;
use Apache::loncommon;
use Apache::lonnet;
use Apache::longroup;
use Apache::lonlocal;
use lib '/home/httpd/lib/perl/';
use LONCAPA;
 

sub handler {
    my $r = shift;

    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
					    ['lastid','group']);
    my ($group,$grouptitle);
    my $cnum=$env{'course.'.$env{'request.course.id'}.'.num'};
    my $cdom=$env{'course.'.$env{'request.course.id'}.'.domain'};
    if (defined($env{'form.group'})) {
        $group = $env{'form.group'};
        if ((! &Apache::lonnet::allowed('pgc',$env{'request.course.id'}.'/'.
				       $group)) &&
           (! &Apache::lonnet::allowed('vcg',$env{'request.course.id'}.
         ($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:'')))) {
            return HTTP_NOT_ACCEPTABLE;
        }
        my %curr_groups = &Apache::longroup::coursegroups($cdom,$cnum,$group);
        if (%curr_groups) {
            my %group_info = 
		&Apache::longroup::get_group_settings($curr_groups{$group});
            $grouptitle = 
		'<b>'.&unescape($group_info{description}).
		'</b><br />';
        }
    } elsif (! &Apache::lonnet::allowed('pch',$env{'request.course.id'}.
             ($env{'request.course.sec'}?'/'.$env{'request.course.sec'}:''))
        ) {
        return HTTP_NOT_ACCEPTABLE;
    }

    my $loaderror=&Apache::lonnet::overloaderror($r);
    if ($loaderror) { return $loaderror; }
    $loaderror=
       &Apache::lonnet::overloaderror($r,
         $env{'course.'.$env{'request.course.id'}.'.home'});
    if ($loaderror) { return $loaderror; }

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

# ------------------------------------------------------------ retrieve entries

    my $chome=$env{'course.'.$env{'request.course.id'}.'.home'};

    my @entries=split(/\:/,
       &Apache::lonnet::reply(
        "chatretr:$cdom:$cnum:$env{'user.domain'}:$env{'user.name'}:$group",
        $chome));
# Figure out what the last valid entry-id is
    my ($lastid,$thentime,$idnum);
    foreach my $entry (@entries) {
	$entry =~/^(\w+)/;
        if ($1 ne 'active_participant') {
	    $lastid=$1;
            ($thentime,$idnum)=split(/\_/,$lastid);
	}
    }
# ----------------------------------------------------------- Can see identity?
    my $seeid = &get_seeid_status();
# -------------------------------------------------------- see which ones apply
    my $include=0;
    my $header;
    my $newstuff='';
    my $bottomid='';
    unless ($env{'form.lastid'}) { 
	$include=1; 
	$header = 
	    &Apache::loncommon::start_page(undef,undef,
					   {'only_body' => 1,
					    'bgcolor'   => '#FFFFFF',
					    'js_ready'  => 1,});
    }
    my @participants=();
    foreach my $entry (@entries) {
	my ($id,$msg,$udom)=split(/\:/,&unescape($entry));
 	if ($id eq 'active_participant') {
           chomp($udom);
	   my $participant= &Apache::loncommon::nickname($msg,$udom);
	   unless ($participant=~/\w/) { $participant=$msg.':'.$udom; }
	   $participants[$#participants+1]=$participant;
	} elsif ($include) {
	    chomp($msg);
	    my ($msgtime,$msgnum)=split(/\_/,$id);
	    my ($sdom,$snum,$anon,$contrib)=split(/\:/,
					     &unescape($msg));
	    $contrib=&unescape($contrib);
	    &Apache::lonfeedback::newline_to_br(\$contrib);
	    ($contrib,my $errors)=&Apache::lontexconvert::msgtexconverted($contrib);
	    if ($errors) { $contrib.=&mt('[Message not fully displayed due to incorrect embedded TeX]'); }
	    if ($errors && $snum eq $env{'user.name'} &&
		$sdom eq $env{'user.domain'} ) {
		$contrib.='<br />'.&mt('[TeX error message: [_1]',$errors);
	    }
	    $contrib=~s/\n/ /g;
	    $contrib=~s/\'/\&\#39\;/g;
	    my $sender='';
	    if ($seeid) {
		$sender=&Apache::loncommon::plainname($snum,$sdom);
		my $nick=&Apache::loncommon::nickname($snum,$sdom);
		if (($nick) && ($nick ne $sender)) {
		    $sender.=' '.$nick;
		}
		unless ($sender) { $sender=$snum.':'.$sdom; }
		if ($anon) { $sender.=' [Anon]' };
	    } elsif (!$anon) {
		$sender=&Apache::loncommon::nickname($snum,$sdom);
		unless ($sender) { $sender=$snum.':'.$sdom; }
	    } else {
		$sender=&Apache::loncommon::screenname($snum,$sdom);
		unless ($sender) { $sender=&mt("Anonymous"); }
	    }
	    $sender=~s/\'/\&\#39\;/g;
	    my $color=$sender;
	    $color=~tr/a-j/0-9/;
	    $color=~tr/A-J/0-9/;
	    $color=~tr/k-t/0-9/;
	    $color=~tr/K-T/0-9/;
	    $color=~tr/u-z/0-5/;
	    $color=~tr/U-Z/0-5/;
	    $color=~s/\D//g;
	    $color=substr($color,0,6);
	    my $timestamp=localtime($msgtime);
	    my ($mhour,$mmin,$msec)=($timestamp=~/(\d\d)\:(\d\d)\:(\d\d)/);
	    $newstuff.='<font color="#'.$color.'"><a name="LC_'.$id.'"></a><b>'.
		$sender.'</b> ('.$mhour.':'.$mmin.':'.$msec.'): '.
		$contrib."</font><br />";
	    $bottomid='LC_'.$id;
	} else {
	    $entry=~/^(\w+)/;
	    if ($1 eq $env{'form.lastid'}) { $include=1; }
	}
    }
    my $participant_output=join('<br />',sort @participants);
    my $refresh_cmd = "/adm/chatfetch?lastid=$lastid";
    if (defined($group)) {
        $refresh_cmd .= "&amp;group=$group";
    }
    my $headarg;
    my ($blocked,$blocktext) = &blockstatus();
    if ($blocked) {
        $newstuff = $blocktext;
        $headarg =  {'only_body' => 1,};
    } else {
        $headarg = {'redirect'  => [5,$refresh_cmd,1],
                                    'only_body' => 1,};
    }
    my $start_page = &Apache::loncommon::start_page('Chat',undef,$headarg); 
    my $end_page = &Apache::loncommon::end_page();
    $r->print(<<ENDDOCUMENT);
$start_page
<script type="text/javascript">
parent.chatout.document.writeln('$header$newstuff');
parent.chatout.scroll(0,10000000);
</script>
$grouptitle
$participant_output
$end_page
ENDDOCUMENT
    return OK;
}

sub get_seeid_status {
    my $crs='/'.$env{'request.course.id'};
    my $seeid;
    if (exists($env{'form.group'})) {
        $seeid = &Apache::lonnet::allowed('rci',$crs.'/'.$env{'form.group'});
    } else {
        if ($env{'request.course.sec'}) {
            $crs.='_'.$env{'request.course.sec'};
        }
        $crs=~s/\_/\//g;
        $seeid=&Apache::lonnet::allowed('rin',$crs);
    }
    return $seeid;
}

sub blockstatus {
    my ($blocked,$output);
    my %setters;
    my ($startblock,$endblock) = &Apache::loncommon::blockcheck(\%setters,'chat');
    if ($startblock && $endblock) {
        $blocked = 1;
        my $endblocktime = &Apache::lonlocal::locallocaltime($endblock);
        $output .= &mt('Chat will be unavailable to you until [_1] because communication is blocked in one or more of your courses: <br/><br />',$endblocktime); 
        foreach my $course (keys(%setters)) {
            my %courseinfo=&Apache::lonnet::coursedescription($course);
            for (my $i=0; $i<@{$setters{$course}{staff}}; $i++) {
                my ($uname,$udom) = @{$setters{$course}{staff}[$i]};
                my $fullname = &Apache::loncommon::plainname($uname,$udom);
                my ($openblock,$closeblock) = @{$setters{$course}{times}[$i]};
                $openblock = &Apache::lonlocal::locallocaltime($openblock);
                $closeblock= &Apache::lonlocal::locallocaltime($closeblock);
                $output .= &mt('Block for [_1] starts: [_2], ends [_3], set by: [_4]<br />',$courseinfo{'description'},$openblock,$closeblock,$fullname);
            }
        }
    }
    return ($blocked,$output);
}

1;
__END__