# The LearningOnline Network with CAPA
# Routines for configuring blocking to collaborative functions, and specific
# resources during an exam 
#
# $Id: lonblockingmenu.pm,v 1.2 2011/12/28 22:09:44 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/
#
###############################################################
##############################################################

=pod

=head1 NAME

lonblockingmenu - Handler to set/modify exam blocks in a course.

=head1 SYNOPSIS

lonblockingmenu provides an interface for setting exam blocks in a course.  

=head1 DESCRIPTION

This module is used to configure blocking of access to collaborative tools
and/or resources during an exam.

=head1 INTERNAL SUBROUTINES

=over

=item &blockstore()

=item &get_dates_from_form()

=item &get_blockdates()

=item &get_block_choices()

=item &display_blocker_status()

=item &display_addblocker_table()

=item &blocktype_text()

=back  

=cut

package Apache::lonblockingmenu;

use strict;
use Apache::lonnet;
use Apache::Constants qw(:common :http);
use Apache::loncommon();
use Apache::lonhtmlcommon();
use HTML::Entities();
use Apache::lonlocal;
use lib '/home/httpd/lib/perl/';
use LONCAPA qw(:DEFAULT :match);

sub handler {
    my $r=shift;

# ----------------------------------------------------------- Set document type

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

    return OK if $r->header_only;

    #  Needs to be in a course
    if (! ($env{'request.course.fn'})) {
        # Not in a course
        $env{'user.error.msg'}=
     "/adm/setblock:dcm:0:0:Cannot set blocking of communications in a course";
        return HTTP_NOT_ACCEPTABLE;
    }

# ----------------------------------------------------------- Permissions check

    unless ((!&Apache::lonnet::allowed('dcm',$env{'request.course.id'})) ||
            (!&Apache::lonnet::allowed('dcm',$env{'request.course.id'}.
                                      '/'.$env{'request.course.sec'}))) {
        return HTTP_NOT_ACCEPTABLE;
    }

# -----------------------------Get action and calling context from query string

    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['action','caller']);

# ----------------------------------------------------------------- Breadcrumbs

    &Apache::lonhtmlcommon::clear_breadcrumbs();
    if ($env{'form.caller'} eq 'email') {  
        &Apache::lonhtmlcommon::add_breadcrumb
            ({href=>'/adm/communicate',
              text=>'Communication/Messages',
              faq=>12,bug=>'Communication Tools',});
    } else {
        &Apache::lonhtmlcommon::add_breadcrumb
            ({href=>'/adm/parmset',
              text=>'Content and Problem Settings'});
    }
    &Apache::lonhtmlcommon::add_breadcrumb
        ({href=>'/adm/setblock',
          text=>'Blocking communication/resource access'});

    $r->print(&Apache::loncommon::start_page('Blocking communication/resource access').
              &Apache::lonhtmlcommon::breadcrumbs('Blocking communication/resource access'));

# ----------------------------------------------------------- Permissions check

    my $usertype;
    my $crstype = &Apache::loncommon::course_type();
    if ($crstype eq 'Community') {
        $usertype = 'members';
    } else {
        $usertype = 'students';
    }
    my $lctype = lc($crstype);
    my %lt=&Apache::lonlocal::texthash(
            'cbds' => 'Communication blocking during scheduled exams',
            'desc' => "You can use communication blocking to prevent $usertype enrolled in this $lctype from displaying LON-CAPA messages sent by other $usertype during an online exam. As blocking of communication could potentially interrupt legitimate communication between $usertype who are also both enrolled in a different LON-CAPA course or community, please be careful that you select the correct start and end times for your scheduled exam when setting or modifying these parameters.",
             'mecb' => 'Modify existing communication blocking periods',
             'ncbc' => 'No communication blocks currently saved',
             'stor' => 'Save',
    );

    my %ltext = &Apache::lonlocal::texthash(
            'dura' => 'Duration',
            'setb' => 'Set by',
            'even' => 'Event',
            'blck' => 'Blocked?',
            'actn' => 'Action',
            'star' => 'Start',
            'endd' => 'End'
    );

    $r->print('<h3>'.$lt{'cbds'}.'</h3>');

    if ($env{'form.action'} eq 'store') {
        &blockstore($r);
    }

    $r->print($lt{'desc'}.'<br /><br />
               <form name="blockform" method="post" action="/adm/setblock?action=store">
             ');

    $r->print('<h4>'.$lt{'mecb'}.'</h4>');
    my %records = ();
    my $blockcount = 0;
    my $parmcount = 0;
    &get_blockdates(\%records,\$blockcount);
    if ($blockcount > 0) {
        $parmcount = &display_blocker_status($r,\%records,\%ltext);
    } else {
        $r->print($lt{'ncbc'}.'<br /><br />');
    }
    &display_addblocker_table($r,$parmcount,\%ltext);
    my $end_page=&Apache::loncommon::end_page();
    $r->print(<<"END");
<br />
<input type="hidden" name="blocktotal" value="$blockcount" />
<input type ="submit" value="$lt{'stor'}" />
</form>
$end_page
END

    $r->print(&Apache::loncommon::end_page());
    return OK;
}

sub blockstore {
    my $r = shift;
    my %lt=&Apache::lonlocal::texthash(
            'tfcm' => 'The following changes were made',
            'ncwm' => 'No changes were made.'
    );
    my %adds = ();
    my %removals = ();
    my %cancels = ();
    my $modtotal = 0;
    my $canceltotal = 0;
    my $addtotal = 0;
    my %blocking = ();
    $r->print('<h3>'.$lt{'head'}.'</h3>');
    foreach my $envkey (keys(%env)) {
        if ($envkey =~ m/^form\.modify_(\d+)$/) {
            $adds{$1} = $1;
            $removals{$1} = $1;
            $modtotal ++;
        } elsif ($envkey =~ m/^form\.cancel_(\d+)$/) {
            $cancels{$1} = $1;
            unless ( defined($removals{$1}) ) {
                $removals{$1} = $1;
                $canceltotal ++;
            }
        } elsif ($envkey =~ m/^form\.add_(\d+)$/) {
            $adds{$1} = $1;
            $addtotal ++;
        }
    }

    foreach my $key (keys(%removals)) {
        my $hashkey = $env{'form.key_'.$key};
        &Apache::lonnet::del('comm_block',["$hashkey"],
                         $env{'course.'.$env{'request.course.id'}.'.domain'},
                         $env{'course.'.$env{'request.course.id'}.'.num'}
                         );
    }
    foreach my $key (keys(%adds)) {
        unless ( defined($cancels{$key}) ) {
            my ($newstart,$newend) = &get_dates_from_form($key);
            my $newkey = $newstart.'____'.$newend;
            my $blocktypes = &get_block_choices($key);
            $blocking{$newkey} = {
                          setter => $env{'user.name'}.':'.$env{'user.domain'},
                          event  => &escape($env{'form.title_'.$key}),
                          blocks => $blocktypes,
                        };
        }
    }
    if ($addtotal + $modtotal > 0) {
        &Apache::lonnet::put('comm_block',\%blocking,
                     $env{'course.'.$env{'request.course.id'}.'.domain'},
                     $env{'course.'.$env{'request.course.id'}.'.num'}
                     );
    }
    my $chgestotal = $canceltotal + $modtotal + $addtotal;
    if ($chgestotal > 0) {
        $r->print($lt{'tfcm'}.'<ul>');
        if ($canceltotal > 0) {
            $r->print('<li>'.&mt('[quant,_1,communication blocking period was,communication blocking periods were] removed.',$canceltotal).'</li>');
        }
        if ($modtotal > 0) {
            $r->print('<li>'.&mt('[quant,_1,communication blocking period was,communication blocking periods were] modified.',$modtotal).'</li>');
        }
        if ($addtotal > 0) {
            $r->print('<li>'.&mt('[quant,_1,communication blocking period was,communication blocking periods were] added.',$addtotal).'</li>');
        }
        $r->print('</ul>');
    } else {
        $r->print($lt{'ncwm'});
    }
    $r->print('<br />');
    return;
}

sub get_dates_from_form {
    my $item = shift;
    my $startdate = &Apache::lonhtmlcommon::get_date_from_form('startdate_'.$item);
    my $enddate   = &Apache::lonhtmlcommon::get_date_from_form('enddate_'.$item);
    return ($startdate,$enddate);
}

sub get_blockdates {
    my ($records,$blockcount) = @_;
    $$blockcount = 0;
    %{$records} = &Apache::lonnet::dump('comm_block',
                         $env{'course.'.$env{'request.course.id'}.'.domain'},
                         $env{'course.'.$env{'request.course.id'}.'.num'}
                         );
    $$blockcount = keys(%{$records});

    if ((keys(%{$records}))[0] =~ /^error: 2 /) {
        $$blockcount = 0;
    }
}

sub get_block_choices {
    my $item = shift;
    my $blocklist;
    my ($typeorder,$types) = &blocktype_text();
    foreach my $type (@{$typeorder}) {
        if ($env{'form.'.$type.'_'.$item}) {
            $blocklist->{$type} = 'on';
        } else {
            $blocklist->{$type} = 'off';
        }
    }
    return $blocklist;
}

sub display_blocker_status {
    my ($r,$records,$ltext) = @_;
    my $parmcount = 0;
 
    my %lt = &Apache::lonlocal::texthash(
        'modi' => 'Modify',
        'canc' => 'Cancel',
    );
    my ($typeorder,$types) = &blocktype_text();
    $r->print(&Apache::loncommon::start_data_table());
    $r->print(<<"END");
  <tr>
    <th>$ltext->{'dura'}</th>
    <th>$ltext->{'setb'}</th>
    <th>$ltext->{'even'}</th>
    <th>$ltext->{'blck'}</th>
    <th>$ltext->{'actn'}</th>
  </tr>
END
    foreach my $record (sort(keys(%{$records}))) {
        my $onchange = 'onFocus="javascript:window.document.forms['.
                       "'blockform'].elements['modify_".$parmcount."'].".
                       'checked=true;"';
        my ($start,$end) = split(/____/,$record);
        my $startform = &Apache::lonhtmlcommon::date_setter('blockform','startdate_'.$parmcount,$start,$onchange);
        my $endform = &Apache::lonhtmlcommon::date_setter('blockform','enddate_'.$parmcount,$end,$onchange);

        my ($setuname,$setudom,$title,$blocks) =
            &Apache::loncommon::parse_block_record($$records{$record});
        $title = &HTML::Entities::encode($title,'"<>&');
        my $settername =
           &Apache::loncommon::aboutmewrapper(
                           &Apache::loncommon::plainname($setuname,$setudom),
                           $setuname,$setudom);
        $r->print(&Apache::loncommon::start_data_table_row());
        $r->print(<<"END");
        <td>$ltext->{'star'}:&nbsp;$startform<br />$ltext->{'endd'}:&nbsp;&nbsp;$endform</td>
        <td>$settername</td>
        <td><input type="text" name="title_$parmcount" size="15" value="$title" /><input type="hidden" name="key_$parmcount" value="$record" /></td>
        <td>
END
        foreach my $block (@{$typeorder}) {
            my $blockstatus = '';
            if ($blocks->{$block} eq 'on') {
                $blockstatus = 'checked="checked"';
            }
            $r->print('<span class="LC_nobreak"><label><input type="checkbox" name="'.$block.'_'.$parmcount.'" '.$blockstatus.' value="1" />'.$types->{$block}.'</label></span><br />');
        }
        $r->print(<<"END");
        </td> 
        <td><span class="LC_nobreak"><label>
        <input type="checkbox" name="modify_$parmcount" />$lt{'modi'}
        </label></span><br /><span class="LC_nobreak">
        <label>
        <input type="checkbox" name="cancel_$parmcount" />$lt{'canc'}
        </label></span>
END
        $r->print(&Apache::loncommon::end_data_table_row());
        $parmcount++;
    }
    $r->print(<<"END");
</table>
<br />
<br />
END
    return $parmcount;
}

sub display_addblocker_table {
    my ($r,$parmcount,$ltext) = @_;
    my $start = time;
    my $end = $start + (60 * 60 * 2); #Default is an exam of 2 hours duration.
    my $onchange = 'onFocus="javascript:window.document.forms['.
                   "'blockform'].elements['add_".$parmcount."'].".
                   'checked=true;"';
    my $startform = &Apache::lonhtmlcommon::date_setter('blockform','startdate_'.$parmcount,$start,$onchange);
    my $endform = &Apache::lonhtmlcommon::date_setter('blockform','enddate_'.$parmcount,$end,$onchange);
    my %lt = &Apache::lonlocal::texthash(
        'addb' => 'Add block',
        'exam' => 'e.g., Exam 1',
        'addn' => 'Add new communication blocking periods'
    );
    my ($typeorder,$types) = &blocktype_text();
    $r->print(<<"END");
<h4>$lt{'addn'}</h4>
END
    $r->print(&Apache::loncommon::start_data_table());
    $r->print(<<"END");
   <tr>
     <th>$ltext->{'dura'}</th>
     <th>$ltext->{'even'} $lt{'exam'}</th>
     <th>$ltext->{'blck'}</th>
     <th>$ltext->{'actn'}</th>
   </tr>
END
    $r->print(&Apache::loncommon::start_data_table_row());
    $r->print(<<"END");
     <td>$ltext->{'star'}:&nbsp;$startform<br />$ltext->{'endd'}:&nbsp;&nbsp;$endform</td>
     <td><input type="text" name="title_$parmcount" size="15" value="" /></td>
     <td>
END
    foreach my $block (@{$typeorder}) {
        $r->print('<span class="LC_nobreak"><label><input type="checkbox" name="'.$block.'_'.$parmcount.'" value="1" />'.$types->{$block}.'</label></span><br />');
     }
     $r->print(<<"END");
     </td>
     <td><span class="LC_nobreak"><label>
     <input type="checkbox" name="add_$parmcount" value="1" />$lt{'addb'}
     </label></span></td>
END
    $r->print(&Apache::loncommon::end_data_table_row());
    $r->print(&Apache::loncommon::end_data_table());
    return;
}

sub blocktype_text {
    my %types = &Apache::lonlocal::texthash(
        'com' => 'Messaging',
        'chat' => 'Chat Room',
        'boards' => 'Discussion',
        'port' => 'Portfolio',
        'groups' => 'Groups',
        'blogs' => 'Blogs',
    );
    my $typeorder = ['com','chat','boards','port','groups','blogs'];
    return ($typeorder,\%types);
}

1;

__END__