# The LearningOnline Network with CAPA
# User Roles Screen
#
# $Id: lonroles.pm,v 1.359 2021/11/30 15:55:40 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

Apache::lonroles - User Roles Screen

=head1 SYNOPSIS

Invoked by /etc/httpd/conf/srm.conf:

 <Location /adm/roles>
 PerlAccessHandler       Apache::lonacc
 SetHandler perl-script
 PerlHandler Apache::lonroles
 ErrorDocument     403 /adm/login
 ErrorDocument	  500 /adm/errorhandler
 </Location>

=head1 OVERVIEW

=head2 Choosing Roles

C<lonroles> is a handler that allows a user to switch roles in
mid-session. LON-CAPA attempts to work with "No Role Specified", the
default role that a user has before selecting a role, as widely as
possible, but certain handlers for example need specification which
course they should act on, etc. Both in this scenario, and when the
handler determines via C<lonnet>'s C<&allowed> function that a certain
action is not allowed, C<lonroles> is used as error handler. This
allows the user to select another role which may have permission to do
what they were trying to do.

=begin latex

\begin{figure}
\begin{center}
\includegraphics[width=0.45\paperwidth,keepaspectratio]{Sample_Roles_Screen}
  \caption{\label{Sample_Roles_Screen}Sample Roles Screen} 
\end{center}
\end{figure}

=end latex

=head2 Role Initialization

The privileges for a user are established at login time and stored in the session environment. As a consequence, a new role does not become active till the next login. Handlers are able to query for privileges using C<lonnet>'s C<&allowed> function. When a user first logs in, their role is the "common" role, which means that they have the sum of all of their privileges. During a session it might become necessary to choose a particular role, which as a consequence also limits the user to only the privileges in that particular role.

=head1 INTRODUCTION

This module enables a user to select what role he wishes to
operate under (instructor, student, teaching assistant, course
coordinator, etc).  These roles are pre-established by the actions
of upper-level users.

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

=head1 HANDLER SUBROUTINE

This routine is called by Apache and mod_perl.

=over 4

=item *

Roles Initialization (yes/no)

=item *

Get Error Message from Environment

=item *

Who is this?

=item *

Generate Page Output

=item *

Choice or no choice

=item *

Table

=item *

Privileges

=back

=cut


package Apache::lonroles;

use strict;
use Apache::lonnet;
use Apache::lonuserstate();
use Apache::Constants qw(:common REDIRECT);
use Apache::File();
use Apache::lonmenu;
use Apache::loncommon;
use Apache::lonhtmlcommon;
use Apache::lonannounce;
use Apache::lonlocal;
use Apache::lonpageflip();
use Apache::lonnavdisplay();
use Apache::loncoursequeueadmin;
use Apache::longroup;
use Apache::lonrss;
use Apache::lonplacementtest;
use GDBM_File;
use LONCAPA qw(:DEFAULT :match);
use HTML::Entities;

my $registered_cleanup;
my $rosterupdates;

sub start_loading_course {
    my ($r,$title) = @_;
    &Apache::loncommon::content_type($r,'text/html');
    &Apache::loncommon::no_cache($r);
    $r->send_http_header;
    my $swinfo=&Apache::lonmenu::rawconfig();
    # Breadcrumbs
    my $brcrum = [{'href' => '',
                   'text' => $title},];
    my $start_page = &Apache::loncommon::start_page($title,undef,
                                                    {'bread_crumbs' => $brcrum,
                                                     'bread_crumbs_nomenu' => 1,
                                                     'links_disabled' => 1});
    $r->print(<<ENDREDIR);
$start_page
<script type="text/javascript">
// <![CDATA[
$swinfo

document.body.addEventListener('click', function (event) {
  // filter out clicks on any other elements
  if (event.target.nodeName == 'A' && event.target.getAttribute('aria-disabled') == 'true') {
    event.preventDefault();
  }
});
// ]]>
</script>
ENDREDIR
    return;
}

sub finish_loading_course {
    my ($r,$msg,$url) = @_;
    my $link = '<div id="LC_course_loaded" style="display:none"><a href="'.$url.'">'.&mt('Continue').'</a></div>';
    my $end_page = &Apache::loncommon::end_page();
    my $js_url = &js_escape($url);
    $r->print(<<END);
$msg
<script type="text/javascript">
// <![CDATA[
\$(document).ready(function() {
    \$("#LC_course_loaded").css("display","block");
    \$('.isDisabled > a').removeAttr("aria-disabled");
    \$('.isDisabled').removeClass("isDisabled");
    var url = "$js_url";
    \$(location).attr('href',url);
});
</script>
$link
$end_page
END
    return;
}

sub redirect_user {
    my ($r,$title,$url,$msg) = @_;
    $msg = $title if (! defined($msg));
    &Apache::loncommon::content_type($r,'text/html');
    &Apache::loncommon::no_cache($r);
    $r->send_http_header;

    my $start_page;
    if ($env{'request.lti.login'}) {
        $start_page = &Apache::loncommon::start_page(undef,undef,
                                                     {'redirect' => [0,$url],}).$msg;
    } else {
        # Breadcrumbs
        my $brcrum = [{'href' => $url,
                       'text' => 'Switching Role'},];
        $start_page = &Apache::loncommon::start_page('Switching Role',undef,
                                                     {'redirect' => [1,$url],
                                                      'bread_crumbs' => $brcrum,}).
                      "\n<p>$msg</p>";
    }
    my $end_page = &Apache::loncommon::end_page();

# Note to style police: 
# This must only replace the spaces, nothing else, or it bombs elsewhere.
    $url=~s/ /\%20/g;
    $r->print(<<ENDREDIR);
$start_page
$end_page
ENDREDIR
    return;
}

sub error_page {
    my ($r,$error,$dest)=@_;
    my %lt = &Apache::lonlocal::texthash(
        pdc => 'Problems during Course Initialization',
        tfp => 'The following problems occurred:',
        con => 'Continue',
    );
    my $end_page = &Apache::loncommon::end_page();
    $dest = &HTML::Entities::encode($dest,'"<>&');
    $r->print(<<END);
<h3>$lt{'pdc'}</h3>
<p class="LC_error">$lt{'tfp'}
<br />
$error
</p><br /><a href="$dest">$lt{'con'}</a>
$end_page
END
    return;
}

sub handler {

    my $r = shift;

    # Check for critical messages and redirect if present.
    my ($redirect,$url) = &Apache::loncommon::critical_redirect(300,'roles');
    if ($redirect) {
        &Apache::loncommon::content_type($r,'text/html');
        $r->header_out(Location => $url);
        return REDIRECT;
    }

    my $now=time;
    my $then=$env{'user.login.time'};
    my $refresh=$env{'user.refresh.time'};
    my $update=$env{'user.update.time'};
    if (!$refresh) {
        $refresh = $then;
    }
    if (!$update) {
        $update = $then;
    }

    my ($norolelist,$blocked_by_ip,$blocked_type,$clientip);
    $clientip = &Apache::lonnet::get_requestor_ip($r);
    if (($env{'request.course.id'}) && ($env{'request.deeplink.login'})) {
        my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
        my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
        my $crstype = $env{'course.'.$env{'request.course.id'}.'.type'};
        my $deeplink_symb = &Apache::loncommon::deeplink_login_symb($cnum,$cdom);
        if ($deeplink_symb) {
            my ($menucoll,$deeplinkmenu,$menuref) = &Apache::loncommon::menucoll_in_effect();
            if (ref($menuref) eq 'HASH') {
                unless (($menuref->{'role'}) || ($env{'request.role.adv'})) {
                    foreach my $envkey (keys(%env)) {
                        next unless ($envkey =~ /^form\./);
                        if ($envkey =~ m{\./($match_domain)/($match_courseid)(?:/(\w+)|$)}) {
                            unless (($1 eq $cdom) && ($2 eq $cnum)) {
                                delete($env{$envkey});
                            }
                        }
                    }
                    if ($env{'form.selectrole'}) {
                        if ($env{'form.switchrole'} =~ m{\./($match_domain)/($match_courseid)(?:/(\w+)|$)}) {
                            unless (($1 eq $cdom) && ($2 eq $cnum)) {
                                delete($env{'form.selectrole'});
                                delete($env{'form.switchrole'});
                            }
                        } elsif ($env{'form.newrole'} =~ m{\./($match_domain)/($match_courseid)(?:/(\w+)|$)}) {
                            unless (($1 eq $cdom) && ($2 eq $cnum)) {
                                delete($env{'form.selectrole'});
                                delete($env{'form.newrole'});
                            }
                        }
                    }
                    $norolelist = 1;
                }
            }
        }
    }

    if ($env{'form.selectrole'}) {
        my ($role,$cdom,$cnum,$rest);
        if ($env{'form.switchrole'} =~ m{^(co|cc|in|ta|ep|ad|st|cr).*?\./($match_domain)/($match_courseid)(/(\w+)|$)}) {
            ($role,$cdom,$cnum,$rest) = ($1,$2,$3,$4);
        } elsif ($env{'form.newrole'} =~ m{^(co|cc|in|ta|ep|ad|st|cr).*?\./($match_domain)/($match_courseid)(/(\w+)|$)}) {
            ($role,$cdom,$cnum,$rest) = ($1,$2,$3,$4);
        }
        if ($cdom ne '') {
            my ($has_evb,$check_ipaccess,$showrole);
            $showrole = 1;
            my $checkrole = "cm./$cdom/$cnum";
            if ($rest ne '') {
                $checkrole .= "/$rest";
            }
            if ((&Apache::lonnet::allowed('evb',undef,undef,$checkrole)) &&
                ($role ne 'st')) {
                $has_evb = 1;
            }
            unless ($has_evb) {
                my @machinedoms = &Apache::lonnet::current_machine_domains();
                my $udom = $env{'user.domain'};
                if ($udom eq $cdom) {
                    $check_ipaccess = 1;
                } elsif (($udom ne '') && (grep(/^\Q$udom\E$/,@machinedoms))) {
                    $check_ipaccess = 1;
                } else {
                    my $lonhost = $Apache::lonnet::perlvar{'lonHostID'};
                    my $internet_names = &Apache::lonnet::get_internet_names($lonhost);
                    my $cprim = &Apache::lonnet::domain($cdom,'primary');
                    my $cintdom = &Apache::lonnet::internet_dom($cprim);
                    if (($cintdom ne '') && (ref($internet_names) eq 'ARRAY')) {
                        if (grep(/^\Q$cintdom\E$/,@{$internet_names})) {
                            $check_ipaccess = 1;
                        }
                    }
                }
                if ($check_ipaccess) {
                    my ($ipaccessref,$cached)=&Apache::lonnet::is_cached_new('ipaccess',$cdom);
                    unless (defined($cached)) {
                        my %domconfig =
                            &Apache::lonnet::get_dom('configuration',['ipaccess'],$cdom);
                        $ipaccessref = &Apache::lonnet::do_cache_new('ipaccess',$cdom,$domconfig{'ipaccess'},1800);
                    }
                    if (ref($ipaccessref) eq 'HASH') {
                        foreach my $id (keys(%{$ipaccessref})) {
                            if (ref($ipaccessref->{$id}) eq 'HASH') {
                                my $range = $ipaccessref->{$id}->{'ip'};
                                if ($range) {
                                    my $type = 'exclude';
                                    if (&Apache::lonnet::ip_match($clientip,$range)) {
                                        $type = 'include';
                                    }
                                    if (ref($ipaccessref->{$id}->{'courses'}) eq 'HASH') {
                                        if ($ipaccessref->{$id}->{'courses'}{$cdom.'_'.$cnum}) {
                                            if ($type eq 'include') {
                                                $showrole = 1;
                                                last;
                                            } else {
                                                $showrole = 0;
                                            }
                                        } else {
                                            if ($type eq 'include') {
                                                $showrole = 0;
                                            } else {
                                                $showrole = 1;
                                            }
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
            unless ($showrole) {
                $blocked_by_ip = 1;
                $blocked_type = &Apache::loncommon::course_type($cdom.'_'.$cnum);
                delete($env{'form.selectrole'});
                delete($env{'form.newrole'});
            }
        }
    }

    $registered_cleanup=0;
    @{$rosterupdates}=();
    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'});

# -------------------------------------------------- Check if setting hot list
    my $hotlist;
    if ($env{'form.action'} eq 'verify_and_change_rolespref') {
        $hotlist = &Apache::lonpreferences::verify_and_change_rolespref($r);
    }

# -------------------------------------------------------- Check for new roles
    my $updateresult;
    if ($env{'form.state'} eq 'doupdate') {
        my $show_course=&Apache::loncommon::show_course();
        my $checkingtxt;
        if ($show_course) {
            $checkingtxt = &mt('Checking for new courses ...');
        } else {
            $checkingtxt = &mt('Checking for new roles ...');
        }
        $updateresult = $checkingtxt;
        $updateresult .= &update_session_roles();
        &Apache::lonnet::appenv({'user.update.time'  => $now});
        $update = $now;
        &Apache::loncoursequeueadmin::reqauthor_check();
    }

# -------------------------------------------------- Check for author requests
    my $reqauthor;
    if ($env{'form.state'} eq 'requestauthor') {
       $reqauthor = &Apache::loncoursequeueadmin::process_reqauthor(\$update);
    }

    my $envkey;
    my %dcroles = ();
    my %helpdeskroles = ();
    my ($numdc,$numhelpdesk,$numadhoc) = 
        &check_for_adhoc(\%dcroles,\%helpdeskroles,$update,$then);
    my $loncaparev = $r->dir_config('lonVersion');

# ================================================================== Roles Init
    if ($env{'form.selectrole'}) {
        if (($env{'request.lti.login'}) && ($env{'request.lti.target'} eq '')) {
            if ($env{'form.ltitarget'} eq 'iframe') {
                &Apache::lonnet::appenv({'request.lti.target' => 'iframe'});
                delete($env{'form.ltitarget'});
            }
        }

        my $locknum=&Apache::lonnet::get_locks();
        if ($locknum) { return 409; }

        my $custom_adhoc;
        if ($env{'form.newrole'}) {
            $env{'form.'.$env{'form.newrole'}}=1;
# Check if this is a Domain Helpdesk or Domain Helpdesk Assistant role trying to enter a course
            if ($env{'form.newrole'} =~ m{^cr/($match_domain)/\1\-domainconfig/\w+\./\1/$match_courseid$}) {
                if ($helpdeskroles{$1}) {
                    $custom_adhoc = 1;
                }
            }
	}
	if ($env{'request.course.id'}) {
            # Check if user is CC trying to select a course role
            if ($env{'form.switchrole'}) {
                my $switch_is_active;
                if (defined($env{'user.role.'.$env{'form.switchrole'}})) {
                    my ($start,$end) = split(/\./,$env{'user.role.'.$env{'form.switchrole'}});
                    if (!$end || $end > $now) {
                        if (!$start || $start < $update) {
                            $switch_is_active = 1;
                        }
                    }
                }
                unless ($switch_is_active) {
                    &adhoc_course_role($refresh,$update,$then);
                }
            }
	    my %temp=('logout_'.$env{'request.course.id'} => time);
	    &Apache::lonnet::put('email_status',\%temp);
	    &Apache::lonnet::delenv('user.state.'.$env{'request.course.id'});
	}
	&Apache::lonnet::appenv({"request.course.id"           => '',
			 	 "request.course.fn"           => '',
				 "request.course.uri"          => '',
				 "request.course.sec"          => '',
                                 "request.course.tied"         => '',
                                 "request.course.timechecked"  => '',
				 "request.role"                => 'cm',
                                 "request.role.adv"            => $env{'user.adv'},
				 "request.role.domain"         => $env{'user.domain'}});
# Check if Domain Helpdesk role trying to enter a course needs privs to be created
        if ($env{'form.newrole'} =~ m{^cr/($match_domain)/\1\-domainconfig/(\w+)\./\1/($match_courseid)(?:/(\w+)|$)}) {
            my $cdom = $1;
            my $rolename = $2;
            my $cnum = $3;
            my $sec = $4;
            if ($custom_adhoc) {
                my ($possroles,$description) = &Apache::lonnet::get_my_adhocroles($cdom.'_'.$cnum,1);
                if (ref($possroles) eq 'ARRAY') {
                    if (grep(/^\Q$rolename\E$/,@{$possroles})) { 
                        if (&Apache::lonnet::check_adhoc_privs($cdom,$cnum,$update,$refresh,$now,
                                                               "cr/$cdom/$cdom".'-domainconfig/'.$rolename,undef,$sec)) {
                            &Apache::lonnet::appenv({"environment.internal.$cdom.$cnum.cr/$cdom/$cdom".'-domainconfig/'."$rolename.adhoc" => time});
                        }
                    }
                }
            }
        } elsif (($numdc > 0) || ($numhelpdesk > 0)) {
# Check if user is a DC trying to enter a course or author space and needs privs to be created
# Check if user is a DH or DA trying to enter a course and needs privs to be created
            foreach my $envkey (keys(%env)) {
# Is this an ad-hoc Coordinator role?
                if ($numdc) {
                    if (my ($ccrole,$domain,$coursenum) =
		        ($envkey =~ m-^form\.(cc|co)\./($match_domain)/($match_courseid)$-)) {
                        if ($dcroles{$domain}) {
                            if (&Apache::lonnet::check_adhoc_privs($domain,$coursenum,
                                                                   $update,$refresh,$now,$ccrole)) {
                                &Apache::lonnet::appenv({"environment.internal.$domain.$coursenum.$ccrole.adhoc" => time});
                            }
                        }
                        last;
                    }
# Is this an ad-hoc CA-role?
                    if (my ($domain,$user) =
		        ($envkey =~ m-^form\.ca\./($match_domain)/($match_username)$-)) {
                        if (($domain eq $env{'user.domain'}) && ($user eq $env{'user.name'})) {
                            delete($env{$envkey});
                            $env{'form.au./'.$domain.'/'} = 1;
                            my ($server_status,$home) = &check_author_homeserver($user,$domain);
                            if ($server_status eq 'switchserver') {
                                my $trolecode = 'au./'.$domain.'/';
                                my $switchserver = '/adm/switchserver?otherserver='.$home.'&amp;role='.$trolecode;
                                $r->internal_redirect($switchserver);
                                return OK;
                            }
                            last;
                        }
                        if (my ($castart,$caend) = ($env{'user.role.ca./'.$domain.'/'.$user} =~ /^(\d*)\.(\d*)$/)) {
                            if (((($castart) && ($castart < $now)) || !$castart) && 
                                ((!$caend) || (($caend) && ($caend > $now)))) {
                                my ($server_status,$home) = &check_author_homeserver($user,$domain);
                                if ($server_status eq 'switchserver') {
                                    my $trolecode = 'ca./'.$domain.'/'.$user;
                                    my $switchserver = '/adm/switchserver?otherserver='.$home.'&amp;role='.$trolecode;
                                    $r->internal_redirect($switchserver);
                                    return OK;
                                }
                                last;
                            }
                        }
                        # Check if author blocked ca-access
                        my %blocked=&Apache::lonnet::get('environment',['domcoord.author'],$domain,$user);
                        if ($blocked{'domcoord.author'} eq 'blocked') {
                            delete($env{$envkey});
                            $env{'user.error.msg'}=':::1:User '.$user.' in domain '.$domain.' blocked domain coordinator access';
                            last;
                        }
                        if ($dcroles{$domain}) {
                            my ($server_status,$home) = &check_author_homeserver($user,$domain);
                            if (($server_status eq 'ok') || ($server_status eq 'switchserver')) {
                                &Apache::lonnet::check_adhoc_privs($domain,$user,$update,
                                                                   $refresh,$now,'ca');
                                if ($server_status eq 'switchserver') {
                                    my $trolecode = 'ca./'.$domain.'/'.$user; 
                                    my $switchserver = '/adm/switchserver?'
                                                      .'otherserver='.$home.'&amp;role='.$trolecode;
                                    $r->internal_redirect($switchserver);
                                    return OK;
                                }
                            } else {
                                delete($env{$envkey});
                            }
                        } else {
                            delete($env{$envkey});
                        }
                        last;
                    }
                }
                if ($numhelpdesk) {
# Is this an ad hoc custom role in a course/community?
                    if (my ($domain,$rolename,$coursenum,$sec) = ($envkey =~ m{^form\.cr/($match_domain)/\1\-domainconfig/(\w+)\./\1/($match_courseid)(?:/(\w+)|$)})) {
                        if ($helpdeskroles{$domain}) {
                            my ($possroles,$description) = &Apache::lonnet::get_my_adhocroles($domain.'_'.$coursenum,1);
                            if (ref($possroles) eq 'ARRAY') {
                                if (grep(/^\Q$rolename\E$/,@{$possroles})) {
                                    if (&Apache::lonnet::check_adhoc_privs($domain,$coursenum,$update,$refresh,$now,
                                                                           "cr/$domain/$domain".'-domainconfig/'.$rolename,
                                                                           undef,$sec)) {
                                        &Apache::lonnet::appenv({"environment.internal.$domain.$coursenum.cr/$domain/$domain".
                                                                 '-domainconfig/'."$rolename.adhoc" => time});
                                    }
                                } else {
                                    delete($env{$envkey});
                                }
                            } else {
                                delete($env{$envkey});
                            }
                        } else {
                            delete($env{$envkey});
                        }
                        last;
                    }
                }
            }
        }
        foreach $envkey (keys(%env)) {
            next if ($envkey!~/^user\.role\./);
            my ($where,$trolecode,$role,$tstatus,$tend,$tstart);
            &Apache::lonnet::role_status($envkey,$update,$refresh,$now,\$role,\$where,
                                         \$trolecode,\$tstatus,\$tstart,\$tend);
            if ($env{'form.'.$trolecode}) {
		if ($tstatus eq 'is') {
		    $where=~s/^\///;
		    my ($cdom,$cnum,$csec)=split(/\//,$where);
                    if (($cnum) && ($role ne 'ca') && ($role ne 'aa')) {
                        my $home = $env{'course.'.$cdom.'_'.$cnum.'.home'};
                        my @ids = &Apache::lonnet::current_machine_ids();
                        unless ($loncaparev eq '' && $home && grep(/^\Q$home\E$/,@ids)) {
                            my %curr_reqd_hash = &Apache::lonnet::userenvironment($cdom,$cnum,'internal.releaserequired');
                            if ($curr_reqd_hash{'internal.releaserequired'} ne '') {
                                my ($switchserver,$switchwarning) =
                                    &Apache::loncommon::check_release_required($loncaparev,$cdom.'_'.$cnum,$trolecode,
                                                                               $curr_reqd_hash{'internal.releaserequired'});
                                if ($switchwarning ne '' || $switchserver ne '') {
                                    &Apache::loncommon::content_type($r,'text/html');
                                    &Apache::loncommon::no_cache($r);
                                    $r->send_http_header;
                                    $r->print(&Apache::loncommon::check_release_result($switchwarning,$switchserver));
                                    return OK;
                                }
                            }
                        }
                    }
# check for course groups
                    my %coursegroups = &Apache::lonnet::get_active_groups(
                          $env{'user.domain'},$env{'user.name'},$cdom, $cnum);
                    my $cgrps = join(':',keys(%coursegroups));

# store role if recent_role list being kept
                    if ($env{'environment.recentroles'}) {
                        my %frozen_roles =
                           &Apache::lonhtmlcommon::get_recent_frozen('roles',$env{'environment.recentrolesn'});
			&Apache::lonhtmlcommon::store_recent('roles',
							     $trolecode,' ',$frozen_roles{$trolecode});
                    }


# check for keyed access
		    if (($role eq 'st') && 
                       ($env{'course.'.$cdom.'_'.$cnum.'.keyaccess'} eq 'yes')) {
# who is key authority?
			my $authdom=$cdom;
			my $authnum=$cnum;
			if ($env{'course.'.$cdom.'_'.$cnum.'.keyauth'}) {
			    ($authnum,$authdom)=
				split(/:/,$env{'course.'.$cdom.'_'.$cnum.'.keyauth'});
			}
# check with key authority
			unless (&Apache::lonnet::validate_access_key(
				     $env{'environment.key.'.$cdom.'_'.$cnum},
					     $authdom,$authnum)) {
# there is no valid key
			     if ($env{'form.newkey'}) {
# student attempts to register a new key
				 &Apache::loncommon::content_type($r,'text/html');
				 &Apache::loncommon::no_cache($r);
				 $r->send_http_header;
				 my $swinfo=&Apache::lonmenu::rawconfig();
				 my $start_page=&Apache::loncommon::start_page
				    ('Verifying Access Key to Unlock this Course');
				 my $end_page=&Apache::loncommon::end_page();
				 my $buttontext=&mt('Enter Course');
				 my $message=&mt('Successfully registered key');
                                 my $ip = &Apache::lonnet::get_requestor_ip();
				 my $assignresult=
				     &Apache::lonnet::assign_access_key(
						     $env{'form.newkey'},
						     $authdom,$authnum,
						     $cdom,$cnum,
                                                     $env{'user.domain'},
						     $env{'user.name'},
                                                     &mt('Assigned from [_1] at [_2] for [_3]'
                                                        ,$ip
                                                        ,&Apache::lonlocal::locallocaltime()
                                                        ,$trolecode)
                                                     );
				 unless ($assignresult eq 'ok') {
				     $assignresult=~s/^error\:\s*//;
				     $message=&mt($assignresult).
				     '<br /><a href="/adm/logout">'.
				     &mt('Logout').'</a>';
				     $buttontext=&mt('Re-Enter Key');
				 }
				 $r->print(<<ENDENTEREDKEY);
$start_page
<script type="text/javascript">
// <![CDATA[
$swinfo
// ]]>
</script>
<form action="" method="post">
<input type="hidden" name="selectrole" value="1" />
<input type="hidden" name="$trolecode" value="1" />
<span class="LC_fontsize_large">$message</span><br />
<input type="submit" value="$buttontext" />
</form>
$end_page
ENDENTEREDKEY
                                 return OK;
			     } else {
# print form to enter a new key
				 &Apache::loncommon::content_type($r,'text/html');
				 &Apache::loncommon::no_cache($r);
				 $r->send_http_header;
				 my $swinfo=&Apache::lonmenu::rawconfig();
				 my $start_page=&Apache::loncommon::start_page
				    ('Enter Access Key to Unlock this Course');
				 my $end_page=&Apache::loncommon::end_page();
				 $r->print(<<ENDENTERKEY);
$start_page
<script type="text/javascript">
// <![CDATA[
$swinfo
// ]]>
</script>
<form action="" method="post">
<input type="hidden" name="selectrole" value="1" />
<input type="hidden" name="$trolecode" value="1" />
<input type="text" size="20" name="newkey" value="$env{'form.newkey'}" />
<input type="submit" value="Enter key" />
</form>
$end_page
ENDENTERKEY
				 return OK;
			     }
			 }
		     }
		    &Apache::lonnet::log($env{'user.domain'},
					 $env{'user.name'},
					 $env{'user.home'},
					 "Role ".$trolecode);

		    &Apache::lonnet::appenv(
					   {'request.role'        => $trolecode,
					    'request.role.domain' => $cdom,
					    'request.course.sec'  => $csec,
                                            'request.course.groups' => $cgrps});
                    my $tadv=0;

		    if (($cnum) && ($role ne 'ca') && ($role ne 'aa')) {
                        if ($role =~ m{^\Qcr/$cdom/$cdom\E\-domainconfig/(\w+)$}) {
                            my $rolename = $1;
                            my %domdef = &Apache::lonnet::get_domain_defaults($cdom);
                            if (ref($domdef{'adhocroles'}) eq 'HASH') {
                                if (ref($domdef{'adhocroles'}{$rolename}) eq 'HASH') {
                                    &Apache::lonnet::appenv({'request.role.desc' => $domdef{'adhocroles'}{$rolename}{'desc'}});
                                }
                            }
                        }
                        my $crstype = &Apache::loncommon::course_type($cdom.'_'.$cnum);
                        $crstype = lc($crstype);
                        my $preamble = '<div id="LC_update_'.$cdom.'_'.$cnum.'" class="LC_info">'.
                                       '<br />'.
                                       &mt("Please be patient while your $crstype loads").
                                       '<br /></div>'.
                                       '<div style="padding:0;clear:both;margin:0;border:0"></div>';
                        my $closure = <<ENDCLOSE;
<script type="text/javascript">
// <![CDATA[
\$("#LC_update_${cdom}_${cnum}").hide('slow');
// ]]>
</script>
ENDCLOSE
                        my $title = &mt("Loading $crstype");
                        &start_loading_course($r,$title);
                        my %prog_state = &Apache::lonhtmlcommon::Create_PrgWin($r,undef,$preamble);
                        &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,&mt('Loading ...'));
                        $r->rflush();
                        my ($msg,$blockcrit,$critmsg_check);
                        $critmsg_check = 1;
                        $blockcrit = &Apache::loncommon::blocking_status('alert',$clientip,$cnum,$cdom,undef,1);
                        if ($blockcrit) {
                            my $checkrole = "cm./$cdom/$cnum";
                            if ($csec ne '') {
                                $checkrole .= "/$csec";
                            }
                            unless ((&Apache::lonnet::allowed('evb',undef,undef,$checkrole)) &&
                                    ($trolecode !~ m{^st\./$cdom/$cnum})) {
                                $critmsg_check = 0;
                            }
                        }
                        my ($furl,$ferr)=
                            &Apache::lonuserstate::readmap($cdom.'/'.$cnum,$critmsg_check);
                        &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,&mt('Finished!'));
                        &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state);
                        $r->print($closure);
                        $r->rflush();
                        if ($ferr) {
                            $furl = '/adm/roles?tryagain=1';
                        } else {
                            &Apache::lonnet::appenv({'request.course.timechecked'=>$now});
                            unless (($env{'form.switchrole'}) || 
                                    ($env{"environment.internal.$cdom.$cnum.$role.adhoc"})) {
                                &Apache::lonnet::put('nohist_crslastlogin',
                                    {$env{'user.name'}.':'.$env{'user.domain'}.
                                     ':'.$csec.':'.$role => $now},$cdom,$cnum);
                            }
                            if (($env{"environment.internal.$cdom.$cnum.$role.adhoc"}) &&
                                (&Apache::lonnet::allowed('vxc',$cdom.'_'.$cnum))) {
                                my $owner = $env{'course.'.$cdom.'_'.$cnum.'.internal.courseowner'};
                                my @coowners = split(/,/,$env{'course.'.$env{'request.course.id'}.'.internal.co-owners'});
                                my %auaccess;
                                foreach my $user ($owner,@coowners) {
                                    my ($cpname,$cpdom) = split(/:/,$user);
                                    my %auroles = &Apache::lonnet::get_my_roles($cpname,$cpdom,'userroles',undef,['au','ca','aa'],[$cdom]);
                                    foreach my $key (keys(%auroles)) {
                                        my ($auname,$audom,$aurole) = split(/:/,$key);
                                        if ($aurole eq 'au') {
                                            $auaccess{$cpname} = 1;
                                        } else {
                                            $auaccess{$auname} = 1;
                                        }
                                    }
                                }
                                &Apache::lonnet::appenv({'request.course.adhocsrcaccess' => join(',',sort(keys(%auaccess))) });
                            }
                            my ($feeds,$syllabus_time);
                            &Apache::lonrss::advertisefeeds($cnum,$cdom,undef,\$feeds);
                            &Apache::lonnet::appenv({'request.course.feeds' => $feeds});
                            &Apache::lonnet::get_numsuppfiles($cnum,$cdom,1);
                            unless ($env{'course.'.$cdom.'_'.$cnum.'.updatedsyllabus'}) {
                                unless (($env{'course.'.$cdom.'_'.$cnum.'.externalsyllabus'}) ||
                                        ($env{'course.'.$cdom.'_'.$cnum.'.uploadedsyllabus'})) {
                                    my %syllabus=&Apache::lonnet::dump('syllabus',$cdom,$cnum);
                                    $syllabus_time = $syllabus{'uploaded.lastmodified'};
                                    if ($syllabus_time) {
                                        &Apache::lonnet::appenv({'request.course.syllabustime' => $syllabus_time});
                                    }
                                }
                            }
                        }
			if (($env{'form.orgurl'}) && 
			    ($env{'form.orgurl'}!~/^\/adm\/flip/) &&
			    ($env{'form.orgurl'} ne '/adm/roles')) {
			    my $dest=$env{'form.orgurl'};
                            if ($env{'form.symb'}) {
                                if ($dest =~ /\?/) {
                                    $dest .= '&';
                                } else {
                                    $dest .= '?';
                                }
                                $dest .= 'symb='.$env{'form.symb'};
                            }
			    if (&Apache::lonnet::allowed('adv') eq 'F') { $tadv=1; }
			    &Apache::lonnet::appenv({'request.role.adv'=>$tadv});
                            if ($ferr) {
                                if ($env{'form.orgurl'}) {
                                    $furl .= '&orgurl='.&HTML::Entities::encode($env{'form.orgurl'},'<>&"');
                                }
                                if ($env{'form.symb'}) {
                                    $furl .= '&symb='.&HTML::Entities::encode($env{'form.symb'},'<>&"');
                                }
                            }
                            if (($ferr) && ($tadv)) {
				&error_page($r,$ferr,$furl);
			    } else {
                                if ($env{'request.course.id'} eq $cdom.'_'.$cnum) {
                                    if (($env{'form.orgurl'} ne '') && ($env{'form.symb'} ne '')) {
                                        unless (&Apache::lonnet::symbverify($env{'form.symb'},$env{'form.orgurl'})) {
                                            $dest=$env{'form.orgurl'};
                                        }
                                    } 
                                }
                                if ($dest =~ m{^/adm/coursedocs\?folderpath}) {
                                    if ($env{'request.course.id'} eq $cdom.'_'.$cnum) { 
                                        my $chome = &Apache::lonnet::homeserver($cnum,$cdom);
                                        &Apache::loncommon::update_content_constraints($cdom,$cnum,$chome,
                                                                                       $cdom.'_'.$cnum);
                                    }
                                }
                                if ($ferr) {
                                    if (!$env{'request.course.id'}) {
                                        &Apache::lonnet::appenv(
                                           {"request.course.id"  => $cdom.'_'.$cnum});
                                        $r->print('<p class="LC_error">'.
                                                  &mt('Could not initialize [_1] at this time.',
                                                      $env{'course.'.$cdom.'_'.$cnum.'.description'}).
                                                  '</p>'.
                                                  '<p><a href="'.$furl.'">'.
                                                  &mt('Please try again.').'</a></p>'.
                                                  &Apache::loncommon::end_page());
                                    }
                                } else {
                                    if (($env{'request.lti.login'}) &&
                                        ($env{'request.lti.rosterid'} || $env{'request.lti.passbackid'})) {
                                        &process_lti($r,$cdom,$cnum);
                                    }
                                    $msg = '<p>'.&mt('Entering [_1] ...',
                                                     $env{'course.'.$cdom.'_'.$cnum.'.description'}).
                                           '</p>';
                                    &finish_loading_course($r,$msg,$dest);
                                }
			    }
                            $r->rflush();
			    return OK;
			} else {
			    if (!$env{'request.course.id'}) {
				&Apache::lonnet::appenv(
				      {"request.course.id"  => $cdom.'_'.$cnum});
			    }
			    if (&Apache::lonnet::allowed('adv') eq 'F') { $tadv=1; }
			    &Apache::lonnet::appenv({'request.role.adv'=>$tadv});
			    if ($ferr) {
                                if ($tadv) {
				    &error_page($r,$ferr,$furl);
                                } else {
                                    $r->print('<p class="LC_error">'.
                                              &mt('Could not initialize [_1] at this time.',
                                                  $env{'course.'.$cdom.'_'.$cnum.'.description'}).
                                              '</p>'.
                                              '<p><a href="'.$furl.'">'.&mt('Please try again.').'</a></p>'.
                                              &Apache::loncommon::end_page());
                                }
			    } else {
                                if (($env{'request.lti.login'}) &&
                                    ($env{'request.lti.rosterid'} || $env{'request.lti.passbackid'})) {
                                    &process_lti($r,$cdom,$cnum);
                                }
				# Check to see if the user is a CC entering a course 
				# for the first time
				if ((($role eq 'cc') || ($role eq 'co')) 
                                    && ($env{'course.'.$cdom.'_'.$cnum.'.course.helper.not.run'})) { 
				    $furl = "/adm/helper/course.initialization.helper";
				    # Send the user to the course they selected
				} elsif ($env{'request.course.id'}) {
                                    if ((&Apache::loncommon::course_type() eq 'Placement') && 
                                        (!$env{'request.role.adv'})) {
                                        my ($score,$incomplete) = 
                                            &Apache::lonplacementtest::check_completion(undef,undef,1);
                                        if (($incomplete) && ($incomplete < 100)) {
                                            $msg = '<p>'.&mt('Entering [_1] ...',
                                                             $env{'course.'.$cdom.'_'.$cnum.'.description'}).
                                                   '</p>';
                                            &finish_loading_course($r,$msg,'/adm/placement');
                                            $r->rflush();
                                            return OK;
                                        }
                                    }
                                    my ($dest,$destsymb,$checkenc);
                                    $dest = $env{'form.destinationurl'};
                                    $destsymb = $env{'form.destsymb'};
                                    if ($dest ne '') {
                                        if ($env{'form.switchrole'}) {
                                            if ($destsymb ne '') {
                                                if ($destsymb !~ m{^/enc/}) {
                                                    unless ($env{'request.role.adv'}) {
                                                        $checkenc = 1;
                                                    }
                                                }
                                            }
                                            if (($dest =~ m{^\Q/public/$cdom/$cnum/syllabus\E.*(\?|\&)usehttp=1}) ||
                                                ($dest =~ m{^\Q/adm/wrapper/ext/\E(?!https:)})) {
                                                if ($ENV{'SERVER_PORT'} == 443) {
                                                    my $hostname = $r->hostname();
                                                    unless ((&Apache::lonnet::uses_sts()) ||
                                                            (&Apache::lonnet::waf_allssl($hostname))) {
                                                        if ($hostname ne '') {
                                                            $dest = 'http://'.$hostname.$dest;
                                                        }
                                                    }
                                                }
                                            }
                                            if ($dest =~ m{^/enc/}) {
                                                if ($env{'request.role.adv'}) {
                                                    $dest = &Apache::lonenc::unencrypted($dest);
                                                    if ($destsymb eq '') {
                                                        ($destsymb) = ($dest =~ /(?:\?|\&)symb=([^\&]*)/);
                                                        $destsymb = &unescape($destsymb);
                                                    }
                                                }
                                            } else {
                                                if ($destsymb eq '') {
                                                    ($destsymb) = ($dest =~ /(?:\?|\&)symb=([^\&]+)/);
                                                    $destsymb = &unescape($destsymb);
                                                }
                                                unless ($env{'request.role.adv'}) {
                                                    $checkenc = 1;
                                                }
                                            }
                                            if (($checkenc) && ($destsymb ne '')) {
                                                my ($encstate,$unencsymb,$res);
                                                $unencsymb = &Apache::lonnet::symbclean($destsymb);
                                                (undef,undef,$res) = &Apache::lonnet::decode_symb($unencsymb);
                                                &Apache::lonnet::symbverify($unencsymb,$res,\$encstate);
                                                if ($encstate) {
                                                    if (($dest ne '') && ($dest !~ m{^/enc/})) {
                                                        $dest=&Apache::lonenc::encrypted($dest);
                                                    }
                                                }
                                            }
                                        }
                                        unless (($dest =~ m{^/enc/}) || ($dest =~ /(\?|\&)symb=.+___\d+___.+/)) {
                                            if (($destsymb ne '') && ($destsymb !~ m{^/enc/})) {
                                                my $esc_symb = &escape($destsymb);
                                                $dest .= (($dest =~/\?/)? '&':'?').'symb='.$esc_symb;
                                            }
                                        }
                                        if ($env{'form.ttoken'}) {
                                            $dest .= (($dest =~/\?/)? '&':'?').'ttoken='.$env{'form.ttoken'};
                                        }
                                        unless ($env{'request.lti.login'}) {
                                            $msg = '<p>'.&mt('Entering [_1] ...',
                                                             $env{'course.'.$cdom.'_'.$cnum.'.description'}).
                                                   '</p>';
                                        }
                                        &finish_loading_course($r,$msg,$dest);
                                        $r->rflush();
                                        return OK;
                                    }
				    if (&Apache::lonnet::allowed('whn',
								 $env{'request.course.id'})
					|| &Apache::lonnet::allowed('whn',
								    $env{'request.course.id'}.'/'
								    .$env{'request.course.sec'})
					) {
					my $startpage = &courseloadpage($env{'request.course.id'});
					unless ($startpage eq 'firstres') {         
					    $msg = '<p>'.&mt('Entering [_1] ...',
						             $env{'course.'.$cdom.'_'.$cnum.'.description'}).
                                                   '</p>';
                                            &finish_loading_course($r,$msg,'/adm/whatsnew?refpage=start');
                                            $r->rflush();
					    return OK;
					}
				    }
				}
                                # Are we allowed to look at the first resource?
                                #
                                # $furl returned by lonuserstate::readmap() has format:
                                # $url?symb=escaped($symb). If the resource has the 
                                # encrypturl parameter in effect, the entire string
                                # $url?symb=escaped($symb) is encrypted as a string
                                # beginning /enc/.
                                # 
                                my ($access,$unencfurl,$unencsymb);
                                if ($furl =~ m{^(.+)(?:\?|\&)symb=([^&]+)(?:$|&)}) {
                                    my ($poss_url,$poss_symb) = ($1,$2);
                                    $unencsymb = &unescape($poss_symb);
                                    $unencfurl = $poss_url;
                                } elsif ($furl =~ m{^/enc/}) {
                                    my $unenc = &Apache::lonenc::unencrypted($furl);
                                    if ($unenc =~ m{^(.+)(?:\?|\&)symb=([^&]+)(?:$|&)}) {
                                        ($unencfurl,$unencsymb) = ($1,$2);
                                        $unencsymb = &unescape($unencsymb);
                                    } else {
                                        $unencfurl = $unenc;
                                    }
                                } else {
                                    $unencfurl = $furl;
                                }
                                if ($unencsymb) {
                                    my $symb = &Apache::lonnet::symbclean($unencsymb);
                                    if (($symb ne '') && (&Apache::lonnet::symbverify($symb,$unencfurl))) {
                                        $access = &Apache::lonnet::allowed('bre',$unencfurl,$symb);
                                    } else {
                                        $access = &Apache::lonnet::allowed('bre',$unencfurl);
                                    }
                                } else {
                                    $access = &Apache::lonnet::allowed('bre',$unencfurl);
                                }
                                if ((!$access) || ($access eq 'B') || ($access eq 'D')) {
                                    $furl = &Apache::lonpageflip::first_accessible_resource();
                                    if ($furl eq '') {
                                        $furl = '/adm/navmaps?showOnlyHomework=1';
                                    }
                                }
                                if ($env{'request.lti.login'}) {
                                    undef($msg);
                                    &finish_loading_course($r,$msg,$furl);
                                } else {
                                    $msg = '<p>'.&mt('Entering [_1] ...',
					              $env{'course.'.$cdom.'_'.$cnum.'.description'}).
                                           '</p>';
                                    &finish_loading_course($r,$msg,$furl);
                                }
			    }
                            $r->rflush();
			    return OK;
			}
		    }
                    #
                    # Send the user to the construction space they selected
                    if ($role =~ /^(au|ca|aa)$/) {
                        my $redirect_url = '/priv/';
                        if ($role eq 'au') {
                            $redirect_url.=$env{'user.domain'}.'/'.$env{'user.name'};
                        } else {
                            $redirect_url .= $where;
                        }
                        $redirect_url .= '/';
                        &redirect_user($r,&mt('Entering Authoring Space'),
                                       $redirect_url);
                        return OK;
                    }
                    if ($role eq 'dc') {
                        my $redirect_url = '/adm/menu/';
                        &redirect_user($r,&mt('Loading Domain Coordinator Menu'),
                                       $redirect_url);
                        return OK;
                    }
                    if ($role eq 'dh') {
                        my $redirect_url = '/adm/menu/';
                        &redirect_user($r,&mt('Loading Domain Helpdesk Menu'),
                                       $redirect_url);
                        return OK;
                    }
                    if ($role eq 'da') {
                        my $redirect_url = '/adm/menu/';
                        &redirect_user($r,&mt('Loading Domain Helpdesk Assistant Menu'),
                                       $redirect_url);
                        return OK;
                    }
                    if ($role eq 'sc') {
                        my $redirect_url = '/adm/grades?command=scantronupload';
                        &redirect_user($r,&mt('Loading Data Upload Page'),
                                       $redirect_url);
                        return OK;
                    }
		}
            }
        }
    }


# =============================================================== No Roles Init

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

    my $crumbtext = 'User Roles';
    my $pagetitle = 'My Roles';
    my $recent = &mt('Recent Roles');
    my $standby = &mt('Role selected. Please stand by.');
    my $show_course=&Apache::loncommon::show_course();
    if ($show_course) {
        $crumbtext = 'Courses';
        $pagetitle = 'My Courses';
        $recent = &mt('Recent Courses');
        $standby = &mt('Course selected. Please stand by.');
    }
    if (($norolelist) && ((split(/:/,$env{'user.error.msg'}))[2])) {
        $crumbtext = 'Access Denied';
        $pagetitle = 'Unauthorized';
    }
    my $brcrum =[{href=>"/adm/roles",text=>$crumbtext}];

    my %roles_in_env;
    my $showcount = &roles_from_env(\%roles_in_env,$update); 

    my $swinfo=&Apache::lonmenu::rawconfig();
    my %domdefs=&Apache::lonnet::get_domain_defaults($env{'user.domain'}); 
    my $cattype = 'std';
    if ($domdefs{'catauth'}) {
        $cattype = $domdefs{'catauth'};
    }
    my $placementonly;
    if ($showcount == 1) {
        if ($env{'request.course.id'}) {
            if ($env{'course.'.$env{'request.course.id'}.'.type'} eq 'Placement') {
                $placementonly = 1;
            }
        } else {
            foreach my $rolecode (keys(%roles_in_env)) {
                my ($cid) = ($rolecode =~ m{^\Quser.role.st./\E($match_domain/$match_courseid)(?:/|$)});
                if ($cid) {
                    my %coursedescription =
                        &Apache::lonnet::coursedescription($cid,{'one_time' => '1'});
                    if ($coursedescription{'type'} eq 'Placement') {
                        $placementonly = 1;
                    }
                    last;
                }
            }
        }
    }
    my ($start_page,$funcs);
    if ($placementonly) {
        $start_page=&Apache::loncommon::start_page($pagetitle,undef,
                                                  {bread_crumbs=>$brcrum,crstype=>'Placement'});
    } else {
        my $crumbsright;
        unless (($norolelist) && ((split(/:/,$env{'user.error.msg'}))[2])) {
            $funcs = &get_roles_functions($showcount,$cattype);
            if ($env{'browser.mobile'}) {
                $crumbsright = $funcs;
                undef($funcs);
            }
        }
        $start_page=&Apache::loncommon::start_page($pagetitle,undef,{bread_crumbs=>$brcrum,
                                                                     bread_crumbs_component=>$crumbsright});
    }
    &js_escape(\$standby);
    my $noscript='<br /><span class="LC_error">'.&mt('Use of LON-CAPA requires Javascript to be enabled in your web browser.').'<br />'.&mt('As this is not the case, most functionality in the system will be unavailable.').'</span><br />';

    $r->print(<<ENDHEADER);
$start_page
$funcs
<noscript>
$noscript
</noscript>
<script type="text/javascript">
// <![CDATA[
$swinfo
window.focus();

active=true;

function enterrole (thisform,rolecode,buttonname) {
    if (active) {
	active=false;
        document.title='$standby';
        window.status='$standby';
	thisform.newrole.value=rolecode;
	thisform.submit();
    } else {
       alert('$standby');
    }
}

function rolesView (caller) {
    if ((caller == 'showall') || (caller == 'noshowall')) {
        document.rolechoice.display.value = caller;
    } else {
        if ((caller == 'doupdate') || (caller == 'requestauthor') ||
            (caller == 'queued')) { 
            document.rolechoice.state.value = caller;
        }
    }
    document.rolechoice.selectrole.value='';
    document.rolechoice.submit();
}

// ]]>
</script>
ENDHEADER

# ------------------------------------------ Get Error Message from Environment

    my ($fn,$priv,$nochoose,$error,$msg)=split(/:/,$env{'user.error.msg'});
    if ($env{'user.error.msg'}) {
	$r->log_reason(
   "$msg for $env{'user.name'} domain $env{'user.domain'} access $priv",$fn);
    }

# ------------------------------------------------- Can this user re-init, etc?

    my $advanced=$env{'user.adv'};
    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['tryagain']);
    my $tryagain=$env{'form.tryagain'};
    my $reinit=$env{'user.reinit'};
    delete $env{'user.reinit'};

# -------------------------------------------------------- Generate Page Output
# --------------------------------------------------------------- Error Header?
    if ($error) {
        $r->print("<h1>".&mt('LON-CAPA Access Control')."</h1>");
	$r->print("<!-- LONCAPAACCESSCONTROLERRORSCREEN --><hr /><pre>");
	if ($priv ne '') {
            $r->print(&mt('Access  : ').&Apache::lonnet::plaintext($priv)."\n");
	}
	if ($fn ne '') {
            $r->print(&mt('Resource: ').&Apache::lonenc::check_encrypt($fn)."\n");
	}
	if ($msg ne '') {
            $r->print(&mt('Action  : ').$msg."\n");
	}
	$r->print("</pre><hr />");
	my $url=$fn;
	my $last;
	if (tie(my %hash,'GDBM_File',$env{'request.course.fn'}.'_symb.db',
		&GDBM_READER(),0640)) {
	    $last=$hash{'last_known'};
	    untie(%hash);
	}
	if ($last) { $fn.='?symb='.&escape($last); }

	&Apache::londocs::changewarning($r,undef,'You have modified your course recently, [_1] may fix this access problem.',
					&Apache::lonenc::check_encrypt($fn));
    } else {
        if ($env{'user.error.msg'}) {
            if ($reinit) {
                $r->print(
 '<h3><span class="LC_error">'.
 &mt('As your session file for the course or community has expired, you will need to re-select it.').'</span></h3>');
            } else {
	        $r->print(
 '<h3><span class="LC_error">'.
 &mt('You need to choose another user role or enter a specific course or community for this function.').
 '</span></h3>');
	    }
        }
    }
    if ($nochoose) {
	$r->print("<h2>".&mt('Sorry ...')."</h2>\n<span class='LC_error'>".
		  &mt('This action is currently not authorized.').'</span>');
        if ($error && $norolelist) {
            $r->print('<br /><br /><h4><span class="LC_error">'.
                      &mt('As your session was launched from a web page external to LON-CAPA some course content may be unavailable, including the resource you were trying to access.').
                     '</span></h4>'.
                     '<h4><span class="LC_error">'.
                     &mt('You may need to login to LON-CAPA directly, or re-launch from a different external system.').
                     '</span></h4>');
        }
        $r->print(&Apache::loncommon::end_page());
	return OK;
    } else {
        if ($updateresult || $reqauthor || $hotlist) {
            my $showresult = '<div>';
            if ($updateresult) {
                $showresult .= &Apache::lonhtmlcommon::confirm_success($updateresult);
            }
            if ($reqauthor) {
                $showresult .= &Apache::lonhtmlcommon::confirm_success($reqauthor);
            }
            if ($hotlist) {
                $showresult .= $hotlist;
            } 
            $showresult .= '</div>';
            $r->print($showresult);
        } elsif ($env{'form.state'} eq 'queued') {
            $r->print(&get_queued());
        }
        if (($ENV{'REDIRECT_QUERY_STRING'}) && ($fn)) {
    	    $fn.='?'.$ENV{'REDIRECT_QUERY_STRING'};
        }
        my $display = ($env{'form.display'} =~ /^(showall)$/);
        $r->print('<form method="post" name="rolechoice" action="'.(($fn)?$fn:$r->uri).'">');
        $r->print('<input type="hidden" name="orgurl" value="'.$fn.'" />');
        $r->print('<input type="hidden" name="selectrole" value="1" />');
        $r->print('<input type="hidden" name="newrole" value="" />');
        $r->print('<input type="hidden" name="display" value="'.$display.'" />');
        $r->print('<input type="hidden" name="state" value="" />');
        if ($blocked_by_ip) {
            my $blocked_role = 'student';
            if ($blocked_type eq 'Community') {
                $blocked_role = 'member';
            }
            $r->print('<h3><span class="LC_error">'.
                      &mt('The [_1] you selected is not available for access with a [_2] role from your current IP address: [_3].',
                          lc($blocked_type),$blocked_role,$clientip).
                      '</span></h3>');
        }
    }
    $r->rflush();

    my (%roletext,%sortrole,%roleclass,%futureroles,%timezones);
    my ($countactive,$countfuture,$inrole,$possiblerole) = 
        &gather_roles($update,$refresh,$now,$reinit,$nochoose,\%roles_in_env,\%roletext,
                      \%sortrole,\%roleclass,\%futureroles,\%timezones,$loncaparev);
    $refresh = $now;
    &Apache::lonnet::appenv({'user.refresh.time'  => $refresh});
    if ($countactive == 1) {
        if ($env{'request.course.id'}) {
            if ($env{'course.'.$env{'request.course.id'}.'.type'} eq 'Placement') {
                $placementonly = 1;
            }
        } elsif ($possiblerole) {
            if ($possiblerole =~ m{^st\./($match_domain)/($match_courseid)(?:/|$)}) {
                if ($env{'course.'.$1.'_'.$2.'.type'} eq 'Placement') {
                    $placementonly = 1;
                }
            }
        }
    }
    if ((($cattype eq 'std') || ($cattype eq 'domonly')) && (!$env{'user.adv'}) &&
          (!$placementonly)) {
        if ($countactive > 0) {
            my $domdesc = &Apache::lonnet::domain($env{'user.domain'},'description');
            my $esc_dom = &HTML::Entities::encode($env{'user.domain'},'"<>&'); 
            $r->print(
                '<p>'
               .&mt('[_1]Visit the [_2]Course/Community Catalog[_3][_4]'
                   .' to view all [_5] LON-CAPA courses and communities.'
                   ,'<b>'
                   ,'<a href="/adm/coursecatalog?showdom='.$esc_dom.'">'
                   ,'</a>'
                   ,'</b>'
                   ,'"'.$domdesc.'"')
               .'<br />'
               .&mt('If a course or community is [_1]not[_2] in your list of current courses and communities below,'
                   .' you may be able to enroll if self-enrollment is permitted.'
                   ,'<b>','</b>')
               .'</p>'
            );
        }
    }

    if ($norolelist) {
        if ($env{'request.role'}) {
            my ($roletext,$role_text_end) = &display_curr_role($env{'request.role'});
            if ($roletext) {
                $r->print(&Apache::loncommon::start_data_table('LC_textsize_mobile').
                          &Apache::loncommon::start_data_table_row().
                          $roletext.
                          &Apache::loncommon::end_data_table_row());
                if ($role_text_end) {
                    $r->print(&Apache::loncommon::continue_data_table_row().
                              $role_text_end.
                              &Apache::loncommon::end_data_table_row());
                }
                $r->print(&Apache::loncommon::end_data_table());
            }
        }
        $r->print(&Apache::loncommon::end_page());
        return OK;
    }

# No active roles
    if ($countactive==0) {
        my $elapsed = 0;
        if ($now && $update) {
            $elapsed = $now - $update;
        }
        &requestcourse_advice($r,$cattype,$inrole,$elapsed); 
	$r->print('</form>');
        if ($countfuture) {
            $r->print(&mt('The following [quant,_1,role,roles] will become active in the future:',$countfuture));
            my $doheaders = &roletable_headers($r,\%roleclass,\%sortrole,
                                               $nochoose);
            &print_rolerows($r,$doheaders,\%roleclass,\%sortrole,\%dcroles,
                            \%roletext,$update,$then);
            my $tremark='';
            my $tbg;
            if ($env{'request.role'} eq 'cm') {
                $tbg="LC_roles_selected";
                $tremark=&mt('Currently selected.').' ';
            } else {
                $tbg="LC_roles_is";
            }
            $r->print(&Apache::loncommon::start_data_table_row()
                     .'<td class="'.$tbg.'">&nbsp;</td>'
                     .'<td colspan="3">'
                     .&mt('No role specified')
                     .'</td>'
                     .'<td>'.$tremark.'&nbsp;</td>'
                     .&Apache::loncommon::end_data_table_row()
            );

            $r->print(&Apache::loncommon::end_data_table());
        }
        $r->print(&Apache::loncommon::end_page());
	return OK;
    } elsif (($placementonly) && ($env{'request.role'} eq 'cm')) {
	$r->print('<h3>'.&mt('Please stand by.').'</h3>
	          <input type="hidden" name="'.$possiblerole.'" value="1" />
                  <noscript><br />
                  <input type="submit" name="submit" value="'.&mt('Continue').'" />
                  </noscript></form>');
	$r->rflush();
	$r->print('<script type="text/javascript">document.forms.rolechoice.submit();</script>');
	$r->print(&Apache::loncommon::end_page());
	return OK;
    }
# ----------------------------------------------------------------------- Table

    if (($numdc > 0) || (($numhelpdesk > 0) && ($numadhoc > 0))) {
        $r->print(&coursepick_jscript().
                  &Apache::loncommon::coursebrowser_javascript());
    }
    if ($numdc > 0) {
        $r->print(&Apache::loncommon::authorbrowser_javascript());
    }

    unless ((!&Apache::loncommon::show_course()) || ($nochoose) || ($countactive==1)) {
	$r->print("<h2>".&mt('Select a Course to Enter')."</h2>\n");
    }
    if ($env{'form.destinationurl'}) {
        $r->print('<input type="hidden" name="destinationurl" value="'.
                  $env{'form.destinationurl'}.'" />');
        if ($env{'form.destsymb'} ne '') {
            $r->print('<input type="hidden" name="destsymb" value="'.
                      $env{'form.destsymb'}.'" />');
        }
    }

    my $doheaders = &roletable_headers($r,\%roleclass,\%sortrole,$nochoose);
    if ($env{'environment.recentroles'}) {
        my %recent_roles =
               &Apache::lonhtmlcommon::get_recent('roles',$env{'environment.recentrolesn'});
	my $output='';
	foreach my $role (sort(keys(%recent_roles))) {
	    if (ref($roletext{'user.role.'.$role}) eq 'ARRAY') {
		$output.= &Apache::loncommon::start_data_table_row().
                          $roletext{'user.role.'.$role}->[0].
                          &Apache::loncommon::end_data_table_row();
                if ($roletext{'user.role.'.$role}->[1] ne '') {
                    $output .= &Apache::loncommon::continue_data_table_row().
                               $roletext{'user.role.'.$role}->[1].
                               &Apache::loncommon::end_data_table_row();
                }
                if ($role =~ m{^dc\./($match_domain)/$} 
		    && $dcroles{$1}) {
		    $output .= &adhoc_roles_row($1,'recent');
                } elsif ($role =~ m{^(dh|da)\./($match_domain)/$}) {
                    $output .= &adhoc_customroles_row($1,$2,'recent',$update,$then);
                }
	    } elsif ($numdc > 0) {
                unless ($role =~/^error\:/) {
                    my ($roletext,$role_text_end) = &display_cc_role('user.role.'.$role);
                    if ($roletext) {
                        $output.= &Apache::loncommon::start_data_table_row().
                                  $roletext.
                                  &Apache::loncommon::end_data_table_row();
                        if ($role_text_end) {
                            $output .= &Apache::loncommon::continue_data_table_row().
                                       $role_text_end.
                                       &Apache::loncommon::end_data_table_row();
                        }
                    }
                }
            }
	}
	if ($output) {
	    $r->print(&Apache::loncommon::start_data_table_empty_row()
                     .'<td align="center" colspan="5">'
                     .$recent
                     .'</td>'
                     .&Apache::loncommon::end_data_table_empty_row()
            );
	    $r->print($output);
            $doheaders ++;
	}
    }
    &print_rolerows($r,$doheaders,\%roleclass,\%sortrole,\%dcroles,\%roletext,$update,$then);
    if ($countactive > 1) {
        my $tremark='';
        my $tbg;
        if ($env{'request.role'} eq 'cm') {
            $tbg="LC_roles_selected";
            $tremark=&mt('Currently selected.').' ';
        } else {
                $tbg="LC_roles_is";
        }
        $r->print(&Apache::loncommon::start_data_table_row());
        unless ($nochoose) {
	    if ($env{'request.role'} ne 'cm') {
	        $r->print('<td class="'.$tbg.'"><input type="submit" value="'.
		          &mt('Select').'" name="cm" /></td>');
	    } else {
	        $r->print('<td class="'.$tbg.'">&nbsp;</td>');
	    }
        }
        $r->print('<td colspan="3">'
                 .&mt('No role specified')
                 .'</td>'
                 .'<td>'.$tremark.'&nbsp;</td>'
                 .&Apache::loncommon::end_data_table_row()
        );
    } 
    $r->print(&Apache::loncommon::end_data_table());
    unless ($nochoose) {
	$r->print("</form>\n");
    }
# ------------------------------------------------------------ Privileges Info
    if (($advanced) && (($env{'user.error.msg'}) || ($error))) {
	$r->print('<hr /><h2>'.&mt('Current Privileges').'</h2>');
	$r->print(&privileges_info());
    }
    my $announcements = &Apache::lonnet::getannounce();
    $r->print(
        '<br />'.
        '<h2>'.&mt('Announcements').'</h2>'.
        $announcements
    ) unless (!$announcements);
    if ($advanced) {
        my $esc_dom = &HTML::Entities::encode($env{'user.domain'},'"<>&');
        $r->print('<p><small><i>'
                 .&mt('This LON-CAPA server is version [_1]',$r->dir_config('lonVersion'))
                 .'</i></small></p>');
    }
    $r->print(&Apache::loncommon::end_page());
    return OK;
}

sub roles_from_env {
    my ($roleshash,$update) = @_;
    my $count = 0;
    if (ref($roleshash) eq 'HASH') {
        foreach my $envkey (keys(%env)) {
            if ($envkey =~ m{^user\.role\.(\w+)[./]}) {
                next if ($1 eq 'gr');
                $roleshash->{$envkey} = $env{$envkey};
                my ($start,$end) = split(/\./,$env{$envkey});
                unless ($end && $end<$update) {
                    $count ++;
                }
            }
        }
    }
    return $count;
}

sub gather_roles {
    my ($update,$refresh,$now,$reinit,$nochoose,$roles_in_env,$roletext,$sortrole,$roleclass,$futureroles,
        $timezones,$loncaparev) = @_;
    my ($countactive,$countfuture,$inrole,$possiblerole) = (0,0,0,'');
    my $advanced = $env{'user.adv'};
    my $tryagain = $env{'form.tryagain'};
    my @ids = &Apache::lonnet::current_machine_ids();
    my (%willtrust,%trustchecked);
    if (ref($roles_in_env) eq 'HASH') {
        my %adhocdesc;
        foreach my $envkey (sort(keys(%{$roles_in_env}))) {
            my $button = 1;
            my $switchserver='';
            my $switchwarning;
            my ($role_text,$role_text_end,$sortkey,$role,$where,$trolecode,$tstart,
                $tend,$tremark,$tstatus,$tpstart,$tpend);
            &Apache::lonnet::role_status($envkey,$update,$refresh,$now,\$role,\$where,
                                         \$trolecode,\$tstatus,\$tstart,\$tend);
            next if (!defined($role) || $role eq '' || $role =~ /^gr/);
            $tremark='';
            $tpstart='&nbsp;';
            $tpend='&nbsp;';
            if ($env{'request.role'} eq $trolecode) {
                $tstatus='selected';
            }
            my $tbg;
            if (($tstatus eq 'is')
                || ($tstatus eq 'selected')
                || ($tstatus eq 'future')
                || ($env{'form.display'} eq 'showall')) {
                my $timezone = &role_timezone($where,$timezones);
                if ($tstart) {
                    $tpstart=&Apache::lonlocal::locallocaltime($tstart,$timezone);
                }
                if ($tend) {
                    $tpend=&Apache::lonlocal::locallocaltime($tend,$timezone);
                }
                if ($tstatus eq 'is') {
                    $tbg='LC_roles_is';
                    $possiblerole=$trolecode;
                    $countactive++;
                } elsif ($tstatus eq 'future') {
                    $tbg='LC_roles_future';
                    $button=0;
                    $futureroles->{$trolecode} = $tstart.':'.$tend;
                    $countfuture ++;
                } elsif ($tstatus eq 'expired') {
                    $tbg='LC_roles_expired';
                    $button=0;
                } elsif ($tstatus eq 'will_not') {
                    $tbg='LC_roles_will_not';
                    $tremark.=&mt('Expired after logout.').' ';
                } elsif ($tstatus eq 'selected') {
                    $tbg='LC_roles_selected';
                    $inrole=1;
                    $countactive++;
                    $tremark.=&mt('Currently selected.').' ';
                }
                my $trole;
                if ($role =~ /^cr\//) {
                    my ($rdummy,$rdomain,$rauthor,$rrole)=split(/\//,$role);
                    unless ($rauthor eq $rdomain.'-domainconfig') {
                        if ($tremark) { $tremark.='<br />'; }
                        $tremark.=&mt('Custom role defined by [_1].',$rauthor.':'.$rdomain);
                    }
                }
                $trole=Apache::lonnet::plaintext($role);
                my $ttype;
                my $twhere;
                my $skipcal;
                my ($tdom,$trest,$tsection)=
                    split(/\//,Apache::lonnet::declutter($where));
                # First, Co-Authorship roles
                if (($role eq 'ca') || ($role eq 'aa')) {
                    my $home = &Apache::lonnet::homeserver($trest,$tdom);
                    my $allowed=0;
                    my $prohibited;
                    foreach my $id (@ids) { if ($id eq $home) { $allowed=1; } }
                    if (!$allowed) {
                        $button=0;
                        unless ($trustchecked{$tdom}) {
                            if ((&Apache::lonnet::will_trust('othcoau',$env{'user.domain'},$tdom)) &&
                                (&Apache::lonnet::will_trust('coaurem',$tdom,$env{'user.domain'}))) {
                                $willtrust{$tdom} = 1;
                                $trustchecked{$tdom} = 1;
                            }
                        } 
                        if ($willtrust{$tdom}) {
                            $switchserver='otherserver='.$home.'&amp;role='.$trolecode;
                        } else {
                            $prohibited = 1;
                            $tremark .= &mt('Session switch required but prohibited.');
                        }
                    }
                    #next if ($home eq 'no_host');
                    $home = &Apache::lonnet::hostname($home);
                    $ttype='Authoring Space';
                    $twhere=&mt('User').': '.$trest.'<br />'.&mt('Domain').
                        ': '.$tdom.'<br />'.
                        ' '.&mt('Server').':&nbsp;'.$home;
                    $env{'course.'.$tdom.'_'.$trest.'.description'}='ca';
                    unless ($prohibited) {
                        $tremark.=&Apache::lonhtmlcommon::authorbombs('/res/'.$tdom.'/'.$trest.'/');
                    }
                    $sortkey=$role."$trest:$tdom";
                } elsif ($role eq 'au') {
                    # Authors
                    my $home = &Apache::lonnet::homeserver
                        ($env{'user.name'},$env{'user.domain'});
                    my $allowed=0;
                    foreach my $id (@ids) { if ($id eq $home) { $allowed=1; } }
                    if (!$allowed) {
                        $button=0;
                        $switchserver='otherserver='.$home.'&amp;role='.$trolecode;
                    }
                    #next if ($home eq 'no_host');
                    $home = &Apache::lonnet::hostname($home);
                    $ttype='Authoring Space';
                    $twhere=&mt('Domain').': '.$tdom.'<br />'.&mt('Server').
                        ':&nbsp;'.$home;
                    $env{'course.'.$tdom.'_'.$trest.'.description'}='ca';
                    $tremark.=&Apache::lonhtmlcommon::authorbombs('/res/'.$tdom.'/'.$env{'user.name'}.'/');
                    $sortkey=$role;
                } elsif ($trest) {
                    my $tcourseid=$tdom.'_'.$trest;
                    $ttype = &Apache::loncommon::course_type($tcourseid);
                    if ($role !~ /^cr/) {
                        $trole = &Apache::lonnet::plaintext($role,$ttype,$tcourseid);
                    } elsif ($role =~ m{^\Qcr/$tdom/$tdom\E\-domainconfig/(\w+)$}) {
                        my $rolename = $1;
                        my $desc;
                        if (ref($adhocdesc{$tdom}) eq 'HASH') {
                            $desc = $adhocdesc{$tdom}{$rolename};
                        } else {
                            my %domdef = &Apache::lonnet::get_domain_defaults($tdom);
                            if (ref($domdef{'adhocroles'}) eq 'HASH') {
                                foreach my $rolename (sort(keys(%{$domdef{'adhocroles'}}))) {
                                    if (ref($domdef{'adhocroles'}{$rolename}) eq 'HASH') {
                                        $adhocdesc{$tdom}{$rolename} = $domdef{'adhocroles'}{$rolename}{'desc'};
                                        $desc = $adhocdesc{$tdom}{$rolename};
                                    }
                                }
                            }
                        }
                        if ($desc ne '') {
                            $trole = $desc;
                        } else {
                            $trole = &mt('Helpdesk[_1]','&nbsp;'.$rolename);
                        }
                    } else {
                        $trole = (split(/\//,$role,4))[-1];
                    }
                    if ($env{'course.'.$tcourseid.'.description'}) {
                        my $home=$env{'course.'.$tcourseid.'.home'};
                        $twhere=$env{'course.'.$tcourseid.'.description'};
                        $sortkey=$role."\0".$tdom."\0".$twhere."\0".$envkey;
                        $twhere = &HTML::Entities::encode($twhere,'"<>&');
                        unless ($twhere eq &mt('Currently not available')) {
                            $twhere.=' <span class="LC_fontsize_small">'.
        &Apache::loncommon::syllabuswrapper(&mt('Syllabus'),$trest,$tdom).
                                    '</span>';
                            unless ($home && grep(/^\Q$home\E$/,@ids) && $loncaparev eq '') {
                                my $required = $env{'course.'.$tcourseid.'.internal.releaserequired'};
                                if ($required ne '') {
                                    ($switchserver,$switchwarning) = 
                                        &Apache::loncommon::check_release_required($loncaparev,$tcourseid,$trolecode,$required);
                                    if ($switchserver || $switchwarning) {
                                        $button = 0;
                                    }
                                }
                            }
                        }
                    } else {
                        my %newhash=&Apache::lonnet::coursedescription($tcourseid);
                        if (%newhash) {
                            $sortkey=$role."\0".$tdom."\0".$newhash{'description'}.
                                "\0".$envkey;
                            $twhere=&HTML::Entities::encode($newhash{'description'},'"<>&').
                                    ' <span class="LC_fontsize_small">'.
                                     &Apache::loncommon::syllabuswrapper(&mt('Syllabus'),$trest,$tdom).
                                    '</span>';
                            $ttype = $newhash{'type'};
                            $trole = &Apache::lonnet::plaintext($role,$ttype,$tcourseid);
                            my $home = $newhash{'home'};
                            unless ($home && grep(/^\Q$home\E$/,@ids) && $loncaparev eq '') {
                                my $required = $newhash{'internal.releaserequired'};
                                if ($required ne '') {
                                    ($switchserver,$switchwarning) =
                                        &Apache::loncommon::check_release_required($loncaparev,$tcourseid,$trolecode,$required);
                                    if ($switchserver || $switchwarning) {
                                        $button = 0;
                                    }
                                }
                            }
                        } else {
                            $twhere=&mt('Currently not available');
                            $env{'course.'.$tcourseid.'.description'}=$twhere;
                            $sortkey=$role."\0".$tdom."\0".$twhere."\0".$envkey;
                            $ttype = 'Unavailable';
                            $skipcal = 1;
                        }
                    }
                    if ($ttype eq 'Placement') {
                        $ttype = 'Placement Test';
                    }
                    if ($tsection) {
                        $twhere.='<br />'.&mt('Section').': '.$tsection;
                    }
                    if ($role ne 'st') { $twhere.="<br />".&mt('Domain').":".$tdom; }
                } elsif ($tdom) {
                    $ttype='Domain';
                    $twhere=$tdom;
                    $sortkey=$role.$twhere;
                } else {
                    $ttype='System';
                    $twhere=&mt('system wide');
                    $sortkey=$role.$twhere;
                }
                ($role_text,$role_text_end) =
                    &build_roletext($trolecode,$tdom,$trest,$tstatus,$tryagain,
                                    $advanced,$tremark,$tbg,$trole,$twhere,$tpstart,
                                    $tpend,$nochoose,$button,$switchserver,$reinit,
                                    $switchwarning,$skipcal);
                $roletext->{$envkey}=[$role_text,$role_text_end];
                if (!$sortkey) {$sortkey=$twhere."\0".$envkey;}
                $sortrole->{$sortkey}=$envkey;
                $roleclass->{$envkey}=$ttype;
            }
        }
    }
    return ($countactive,$countfuture,$inrole,$possiblerole);
}

sub role_timezone {
    my ($where,$timezones) = @_;
    my $timezone;
    if (ref($timezones) eq 'HASH') { 
        if ($where =~ m{^/($match_domain)/($match_courseid)}) {
            my $cdom = $1;
            my $cnum = $2;
            if ($cdom && $cnum) {
                if (!exists($timezones->{$cdom.'_'.$cnum})) {
                    my $tz;
                    if ($env{'course.'.$cdom.'_'.$cnum.'.description'}) {
                        $tz = $env{'course.'.$cdom.'_'.$cnum.'.timezone'};
                    } else {
                        my %timehash =
                            &Apache::lonnet::get('environment',['timezone'],$cdom,$cnum);
                        $tz = $timehash{'timezone'};
                    }
                    if ($tz eq '') {
                        if (!exists($timezones->{$cdom})) {
                            my %domdefaults = 
                                &Apache::lonnet::get_domain_defaults($cdom);
                            if ($domdefaults{'timezone_def'} eq '') {
                                $timezones->{$cdom} = 'local';
                            } else {
                                $timezones->{$cdom} = $domdefaults{'timezone_def'};
                            }
                        }
                        $timezones->{$cdom.'_'.$cnum} = $timezones->{$cdom};
                    } else {
                        $timezones->{$cdom.'_'.$cnum} = 
                            &Apache::lonlocal::gettimezone($tz);
                    }
                }
                $timezone = $timezones->{$cdom.'_'.$cnum};
            }
        } else {
            my ($tdom) = ($where =~ m{^/($match_domain)});
            if ($tdom) {
                if (!exists($timezones->{$tdom})) {
                    my %domdefaults = &Apache::lonnet::get_domain_defaults($tdom);
                    if ($domdefaults{'timezone_def'} eq '') {
                        $timezones->{$tdom} = 'local';
                    } else {
                        $timezones->{$tdom} = $domdefaults{'timezone_def'};
                    }
                }
                $timezone = $timezones->{$tdom};
            }
        }
        if ($timezone eq 'local') {
            $timezone = undef;
        }
    }
    return $timezone;
}

sub roletable_headers {
    my ($r,$roleclass,$sortrole,$nochoose) = @_;
    my $doheaders;
    if ((ref($sortrole) eq 'HASH') && (ref($roleclass) eq 'HASH')) {
        $r->print('<br />'
                 .&Apache::loncommon::start_data_table('LC_textsize_mobile')
                 .&Apache::loncommon::start_data_table_header_row()
        );
        if (!$nochoose) { $r->print('<th>&nbsp;</th>'); }
        $r->print('<th>'.&mt('User Role').'</th>'
                 .'<th>'.&mt('Extent').'</th>'
                 .'<th>'.&mt('Start').'</th>'
                 .'<th>'.&mt('End').'</th>'
                 .&Apache::loncommon::end_data_table_header_row()
        );
        $doheaders=-1;
        my @roletypes = &roletypes();
        foreach my $type (@roletypes) {
            my $haverole=0;
            foreach my $which (sort {uc($a) cmp uc($b)} (keys(%{$sortrole}))) {
                if ($roleclass->{$sortrole->{$which}} =~ /^\Q$type\E/) {
                    $haverole=1;
                }
            }
            if ($haverole) { $doheaders++; }
        }
    }
    return $doheaders;
}

sub roletypes {
    my @types = ('Domain','Authoring Space','Course','Placement Test','Community','Unavailable','System');
    return @types; 
}

sub print_rolerows {
    my ($r,$doheaders,$roleclass,$sortrole,$dcroles,$roletext,$update,$then) = @_;
    if ((ref($roleclass) eq 'HASH') && (ref($sortrole) eq 'HASH')) {
        my @types = &roletypes();
        foreach my $type (@types) {
            my $output;
            foreach my $which (sort {uc($a) cmp uc($b)} (keys(%{$sortrole}))) {
                if ($roleclass->{$sortrole->{$which}} =~ /^\Q$type\E/) {
                    if (ref($roletext) eq 'HASH') {
                        if (ref($roletext->{$sortrole->{$which}}) eq 'ARRAY') {
                            $output.= &Apache::loncommon::start_data_table_row().
                                      $roletext->{$sortrole->{$which}}->[0].
                                      &Apache::loncommon::end_data_table_row();
                            if ($roletext->{$sortrole->{$which}}->[1] ne '') {
                                $output .= &Apache::loncommon::continue_data_table_row().
                                           $roletext->{$sortrole->{$which}}->[1].
                                           &Apache::loncommon::end_data_table_row();
                            }
                        }
                        if ($sortrole->{$which} =~ m{^user\.role\.dc\./($match_domain)/}) {
                            if (ref($dcroles) eq 'HASH') {
                                if ($dcroles->{$1}) {
                                    $output .= &adhoc_roles_row($1,'');
                                }
                            }
                        } elsif ($sortrole->{$which} =~ m{^user\.role\.(dh|da)\./($match_domain)/}) {
                            $output .= &adhoc_customroles_row($1,$2,'',$update,$then);
                        }
                    }
                }
            }
            if ($output) {
                if ($doheaders > 0) {
                    $r->print(&Apache::loncommon::start_data_table_empty_row()
                             .'<td align="center" colspan="5">'
                             .&mt($type)
                             .'</td>'
                             .&Apache::loncommon::end_data_table_empty_row()
                    );
                }
                $r->print($output);
            }
        }
    }
}

sub findcourse_advice {
    my ($r,$cattype,$elapsed) = @_;
    my $domdesc = &Apache::lonnet::domain($env{'user.domain'},'description');
    my $esc_dom = &HTML::Entities::encode($env{'user.domain'},'"<>&');
    if (&Apache::lonnet::auto_run(undef,$env{'user.domain'})) {
        $r->print('<p>'.&mt('If you were expecting to see an active role listed for a particular course in the [_1] domain, it may be missing for one of the following reasons:',$domdesc).'
<ul>
 <li>'.&mt('The course has yet to be created.').'</li>
 <li>'.&mt('Automatic enrollment of registered students has not been enabled for the course.').'</li>
 <li>'.&mt('You are in a section of course for which automatic enrollment in the corresponding LON-CAPA course is not active.').'</li>
 <li>'.&mt('The start date for automated enrollment has yet to be reached.').'</li>
 <li>'.&mt('You registered for the course recently and there is a time lag between the time you register, and the time this information becomes available for the update of LON-CAPA course rosters.').'</li>
 <li>'.&mt('Automated enrollment added you to the course in the time since you last logged-in.').' '.&mt('If that is the case you can use the "Check for changes" link in the gray Functions bar to update the list of your available course roles.').'</li>   
 </ul></p>');
    } else {
        $r->print('<p>'.&mt('If you were expecting to see an active role listed for a particular course, that course may not have been created yet.').'</p>');
        if ($elapsed > 600) {
            $r->print('<p>'.&mt('You may also have been assigned to a course in the time since you last logged-in, or checked for changes').
                      '<br />'.
                      &mt('If that is the case you can use the "Check for changes" link in the gray Functions bar to update the list of your available course roles.').'</p>');
        }  
    }
    if (($cattype eq 'std') || ($cattype eq 'domonly')) {
        $r->print('<h3>'.&mt('Self-Enrollment').'</h3>'.
                  '<p>'.&mt('The [_1]Course/Community Catalog[_2] provides information about all [_3] classes for which LON-CAPA courses have been created, as well as any communities in the domain.','<a href="/adm/coursecatalog?showdom='.$esc_dom.'">','</a>',$domdesc).'<br />');
        $r->print(&mt('You can search for courses and communities which permit self-enrollment, if you would like to enroll in one.').'</p>'.
        &Apache::loncoursequeueadmin::queued_selfenrollment());
    }
    return;
}

sub requestcourse_advice {
    my ($r,$cattype,$inrole,$elapsed) = @_;
    my $domdesc = &Apache::lonnet::domain($env{'user.domain'},'description');
    my $esc_dom = &HTML::Entities::encode($env{'user.domain'},'"<>&');
    my (%can_request,%request_doms,$output);
    &Apache::lonnet::check_can_request($env{'user.domain'},\%can_request,\%request_doms);
    if (keys(%request_doms) > 0) {
        my ($types,$typename) = &Apache::loncommon::course_types();
        if ((ref($types) eq 'ARRAY') && (ref($typename) eq 'HASH')) { 
            my (@reqdoms,@reqtypes);
            foreach my $type (sort(keys(%request_doms))) {
                push(@reqtypes,$type); 
                if (ref($request_doms{$type}) eq 'ARRAY') {
                    my $domstr = join(', ',map { &Apache::lonnet::domain($_) } sort(@{$request_doms{$type}}));
                    $output .=
                        '<li>'
                       .&mt('[_1]'.$typename->{$type}.'[_2] in domain: [_3]',
                            '<i>',
                            '</i>',
                            '<b>'.$domstr.'</b>')
                       .'</li>';
                    foreach my $dom (@{$request_doms{$type}}) {
                        unless (grep(/^\Q$dom\E/,@reqdoms)) {
                            push(@reqdoms,$dom);
                        }
                    }
                }
            }
            my @showtypes;
            foreach my $type (@{$types}) {
                if (grep(/^\Q$type\E$/,@reqtypes)) {
                    push(@showtypes,$type);
                }
            }
            my $requrl = '/adm/requestcourse';
            if (@reqdoms == 1) {
                $requrl .= '?showdom='.$reqdoms[0];
            }
            if (@showtypes > 0) {
                $requrl.=(($requrl=~/\?/)?'&':'?').'crstype='.$showtypes[0];
            }
            if (@reqdoms == 1 || @showtypes > 0) {
                $requrl .= '&state=crstype&action=new';
            }
            if ($output) {
                $r->print('<h3>'.&mt('Request creation of a course or community').'</h3>'.
                          '<p>'.
                          &mt('You have rights to request the creation of courses and/or communities in the following domain(s):').
                          '<ul>'.
                          $output.
                          '</ul>'.
                          &mt('Use the [_1]request form[_2] to submit a request for creation of a new course or community.',
                              '<a href="'.$requrl.'">','</a>').
                          '</p>');
            }
        }
    } elsif (!$env{'user.adv'}) {
       if ($inrole) {
            $r->print('<h3>'.&mt('Currently no additional roles, courses or communities').'</h3>');
        } else {
            $r->print('<h3>'.&mt('Currently no active roles, courses or communities').'</h3>');
        }
        &findcourse_advice($r,$cattype,$elapsed);
    }
    return;
}

sub privileges_info {
    my ($which) = @_;
    my $output;

    $which ||= $env{'request.role'};

    foreach my $envkey (sort(keys(%env))) {
	next if ($envkey!~/^user\.priv\.\Q$which\E\.(.*)/);

	my $where=$1;
	my $ttype;
	my $twhere;
	my (undef,$tdom,$trest,$tsec)=split(m{/},$where);
	if ($trest) {
	    if ($env{'course.'.$tdom.'_'.$trest.'.description'} eq 'ca') {
		$ttype='Authoring Space';
		$twhere='User: '.$trest.', Domain: '.$tdom;
	    } else {
		$ttype= &Apache::loncommon::course_type($tdom.'_'.$trest);
		$twhere=$env{'course.'.$tdom.'_'.$trest.'.description'};
		if ($tsec) {
		    my $sec_type = 'Section';
		    if (exists($env{"user.role.gr.$where"})) {
			$sec_type = 'Group';
		    }
		    $twhere.=' ('.$sec_type.': '.$tsec.')';
		}
	    }
	} elsif ($tdom) {
	    $ttype='Domain';
	    $twhere=$tdom;
	} else {
	    $ttype='System';
	    $twhere='/';
	}
	$output .= "\n<h3>".&mt($ttype).': '.$twhere.'</h3>'."\n<ul>";
	foreach my $priv (sort(split(/:/,$env{$envkey}))) {
	    next if (!$priv);

	    my ($prv,$restr)=split(/\&/,$priv);
	    my $trestr='';
	    if ($restr ne 'F') {
		$trestr.=' ('.
		    join(', ',
			 map { &Apache::lonnet::plaintext($_) } 
			     (split('',$restr))).') ';
	    }
	    $output .= "\n\t".
		'<li>'.&Apache::lonnet::plaintext($prv).$trestr.'</li>';
	}
	$output .= "\n".'</ul>';
    }
    return $output;
}

sub build_roletext {
    my ($trolecode,$tdom,$trest,$tstatus,$tryagain,$advanced,$tremark,$tbg,$trole,$twhere,
        $tpstart,$tpend,$nochoose,$button,$switchserver,$reinit,$switchwarning,$skipcal) = @_;
    my ($roletext,$roletext_end,$poss_adhoc);
    if ($trolecode =~ m/^d(c|h|a)\./) {
        $poss_adhoc = 1;
    }
    my $rowspan=($poss_adhoc) ? ''
                         : ' rowspan="2" ';

    unless ($nochoose) {
        my $buttonname=$trolecode;
        $buttonname=~s/\W//g;
        if (!$button) {
            if ($switchserver) {
                $roletext.='<td'.$rowspan.' class="'.$tbg.'">'
                          .'<a href="/adm/switchserver?'.$switchserver.'">'
                          .&mt('Switch Server')
                          .'</a></td>';
            } else {
                $roletext.=('<td'.$rowspan.' class="'.$tbg.'">&nbsp;</td>');
            }
            if ($switchwarning) {
                if ($tremark eq '') {
                    $tremark = $switchwarning;
                } else {
                    $tremark .= '<br />'.$switchwarning;
                }
            }
        } elsif ($tstatus eq 'is') {
            $roletext.='<td'.$rowspan.' class="'.$tbg.'">'.
                        '<input name="'.$buttonname.'" type="button" value="'.
                        &mt('Select').'" onclick="javascript:enterrole(this.form,\''.
                        $trolecode."','".$buttonname.'\');" /></td>';
        } elsif ($tryagain) {
            $roletext.=
                '<td'.$rowspan.' class="'.$tbg.'">'.
                '<input name="'.$buttonname.'" type="button" value="'.
                &mt('Try Selecting Again').'" onclick="javascript:enterrole(this.form,\''.
                        $trolecode."','".$buttonname.'\');" /></td>';
        } elsif ($advanced) {
            $roletext.=
                '<td'.$rowspan.' class="'.$tbg.'">'.
                '<input name="'.$buttonname.'" type="button" value="'.
                &mt('Re-Initialize').'" onclick="javascript:enterrole(this.form,\''.
                        $trolecode."','".$buttonname.'\');" /></td>';
        } elsif ($reinit) {
            $roletext.= 
                '<td'.$rowspan.' class="'.$tbg.'">'.
                '<input name="'.$buttonname.'" type="button" value="'.
                &mt('Re-Select').'" onclick="javascript:enterrole(this.form,\''.
                        $trolecode."','".$buttonname.'\');" /></td>';
        } else {
            $roletext.=
                '<td'.$rowspan.' class="'.$tbg.'">'.
                '<input name="'.$buttonname.'" type="button" value="'.
                &mt('Re-Select').'" onclick="javascript:enterrole(this.form,\''.
                        $trolecode."','".$buttonname.'\');" /></td>';
        }
    }
    if (($trolecode !~ m/^(dc|ca|au|aa)\./)  && (!$skipcal)) {
	$tremark.=&Apache::lonannounce::showday(time,1,
			 &Apache::lonannounce::readcalendar($tdom.'_'.$trest));
    }
    $roletext.='<td>'.$trole.'</td>'
              .'<td>'.$twhere.'</td>'
              .'<td>'.$tpstart.'</td>'
              .'<td>'.$tpend.'</td>';
    unless ($poss_adhoc) {
        $roletext_end = '<td colspan="4">'.
                        $tremark.'&nbsp;'.
                        '</td>';
    }
    return ($roletext,$roletext_end);
}

sub check_author_homeserver {
    my ($uname,$udom)=@_;
    if (($uname eq '') || ($udom eq '')) {
        return ('fail','');
    }
    my $home = &Apache::lonnet::homeserver($uname,$udom);
    if (&Apache::lonnet::host_domain($home) ne $udom) {
        return ('fail',$home);
    }
    my @ids=&Apache::lonnet::current_machine_ids();
    if (grep(/^\Q$home\E$/,@ids)) {
        return ('ok',$home);
    } else {
        return ('switchserver',$home);
    }
}

sub check_for_adhoc {
    my ($dcroles,$helpdeskroles,$update,$then) = @_;
    my $numdc = 0;
    my $numhelpdesk = 0;
    my $numadhoc = 0;
    my $num_custom_adhoc = 0; 
    if (($env{'user.adv'}) || ($env{'user.rar'})) {
        foreach my $envkey (sort(keys(%env))) {
            if ($envkey=~/^user\.role\.(dc|dh|da)\.\/($match_domain)\/$/) {
                my $role = $1;
                my $roledom = $2;
                my $liverole = 1;
                my ($tstart,$tend)=split(/\./,$env{$envkey});
                my $limit = $update;
                if ($env{'request.role'} eq "$role./$roledom/") {
                    $limit = $then;
                }
                if ($tstart && $tstart>$limit) { $liverole = 0; }
                if ($tend   && $tend  <$limit) { $liverole = 0; }
                if ($liverole) {
                    if ($role eq 'dc') {
                        $dcroles->{$roledom} = $envkey;
                        $numdc++;
                    } else {
                        $helpdeskroles->{$roledom} = $envkey;
                        my %domdefaults = &Apache::lonnet::get_domain_defaults($roledom);
                        if (ref($domdefaults{'adhocroles'}) eq 'HASH') {
                            if (keys(%{$domdefaults{'adhocroles'}})) {
                                $numadhoc ++;
                            }
                        }
                        $numhelpdesk++;
                    }
                }
            }
        }
    }
    return ($numdc,$numhelpdesk,$numadhoc);
}

sub adhoc_course_role {
    my ($refresh,$update,$then) = @_;
    my ($cdom,$cnum,$crstype);
    $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
    $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
    $crstype = &Apache::loncommon::course_type();
    if (&check_forcc($cdom,$cnum,$refresh,$update,$then,$crstype)) {
        my $setprivs;
        if (!defined($env{'user.role.'.$env{'form.switchrole'}})) {
            $setprivs = 1;
        } else {
            my ($start,$end) = split(/\./,$env{'user.role.'.$env{'form.switchrole'}});
            if (($start && ($start>$refresh || $start == -1)) ||
                ($end && $end<$update)) {
                $setprivs = 1;
            }
        }
        unless ($setprivs) {
            if (!exists($env{'user.priv.'.$env{'form.switchrole'}.'./'})) {
                $setprivs = 1;
            }
        }
        if ($setprivs) {
            if ($env{'form.switchrole'} =~ m-^(in|ta|ep|ad|st|cr)(.*?)\./\Q$cdom\E/\Q$cnum\E/?(\w*)$-) {
                my $role = $1;
                my $custom_role = $2;
                my $usec = $3;
                if ($role eq 'cr') {
                    if ($custom_role =~ m-^/$match_domain/$match_username/\w+$-) {
                        $role .= $custom_role;
                    } else {
                        return;
                    }
                }
                my (%userroles,%newrole,%newgroups,%group_privs);
                my %cgroups =
                    &Apache::lonnet::get_active_groups($env{'user.domain'},
                                            $env{'user.name'},$cdom,$cnum);
                my $ccrole;
                if ($crstype eq 'Community') {
                    $ccrole = 'co';
                } else {
                    $ccrole = 'cc';
                }
                foreach my $group (keys(%cgroups)) {
                    $group_privs{$group} =
                        $env{'user.priv.'.$ccrole.'./'.$cdom.'/'.$cnum.'./'.$cdom.'/'.$cnum.'/'.$group};
                }
                $newgroups{'/'.$cdom.'/'.$cnum} = \%group_privs;
                my $area = '/'.$cdom.'/'.$cnum;
                my $spec = $role.'.'.$area;
                if ($usec ne '') {
                    $spec .= '/'.$usec;
                    $area .= '/'.$usec;
                }
                if ($role =~ /^cr/) {
                    &Apache::lonnet::custom_roleprivs(\%newrole,$role,$cdom,$cnum,$spec,$area);
                } else {
                    &Apache::lonnet::standard_roleprivs(\%newrole,$role,$cdom,$spec,$cnum,$area);
                }
                &Apache::lonnet::set_userprivs(\%userroles,\%newrole,\%newgroups);
                my $adhocstart = $refresh-1;
                $userroles{'user.role.'.$spec} = $adhocstart.'.';
                &Apache::lonnet::appenv(\%userroles,[$role,'cm']);
            }
        }
    }
    return;
}

sub check_forcc {
    my ($cdom,$cnum,$refresh,$update,$then,$crstype) = @_;
    my ($is_cc,$ccrole);
    if ($crstype eq 'Community') {
        $ccrole = 'co';
    } else {
        $ccrole = 'cc';
    }
    if (&Apache::lonnet::is_course($cdom,$cnum)) {
        my $envkey = 'user.role.'.$ccrole.'./'.$cdom.'/'.$cnum;
        if (defined($env{$envkey})) {
            $is_cc = 1;
            my ($tstart,$tend)=split(/\./,$env{$envkey});
            my $limit = $update;
            if ($env{'request.role'} eq $ccrole.'./'.$cdom.'/'.$cnum) {
                $limit = $then;
            }
            if ($tstart && $tstart>$refresh) { $is_cc = 0; }
            if ($tend   && $tend  <$limit) { $is_cc = 0; }
        }
    }
    return $is_cc;
}

sub courselink {
    my ($roledom,$rowtype,$role) = @_;
    my $courseform=&Apache::loncommon::selectcourse_link
                   ('rolechoice','course'.$rowtype.'_'.$roledom.'_'.$role,
                    'domain'.$rowtype.'_'.$roledom.'_'.$role,
                    'coursedesc'.$rowtype.'_'.$roledom.'_'.$role,
                    $roledom.':'.$role,undef,'Course/Community');
    my $hiddenitems = '<input type="hidden" name="domain'.$rowtype.'_'.$roledom.'_'.$role.'" value="'.$roledom.'" />'.
                      '<input type="hidden" name="origdom'.$rowtype.'_'.$roledom.'_'.$role.'" value="'.$roledom.'" />'.
                      '<input type="hidden" name="course'.$rowtype.'_'.$roledom.'_'.$role.'" value="" />'.
                      '<input type="hidden" name="coursedesc'.$rowtype.'_'.$roledom.'_'.$role.'" value="" />';
    return $courseform.$hiddenitems;
}

sub coursepick_jscript {
    my %js_lt = &Apache::lonlocal::texthash(
                  plsu => "Please use the 'Select Course/Community' link to open a separate pick course window where you may select the course or community you wish to enter.",
                  youc => 'You can only use this screen to select courses and communities in the current domain.',
             );
    &js_escape(\%js_lt);
    my $verify_script = <<"END";
<script type="text/javascript">
// <![CDATA[
function verifyCoursePick(caller) {
    var numbutton = getIndex(caller)
    var pickedCourse = document.rolechoice.elements[numbutton+4].value
    var pickedDomain = document.rolechoice.elements[numbutton+2].value
    if (document.rolechoice.elements[numbutton+2].value == document.rolechoice.elements[numbutton+3].value) {
        if (pickedCourse != '') {
            if (numbutton != -1) {
                var courseTarget = "cc./"+pickedDomain+"/"+pickedCourse
                document.rolechoice.elements[numbutton+1].name = courseTarget
                document.rolechoice.submit()
            }
        }
        else {
            alert("$js_lt{'plsu'}");
        }
    }
    else {
        alert("$js_lt{'youc'}")
    }
}
function getIndex(caller) {
    for (var i=0;i<document.rolechoice.elements.length;i++) {
        if (document.rolechoice.elements[i] == caller) {
            return i;
        }
    }
    return -1;
}
// ]]>
</script>
END
    return $verify_script;
}

sub coauthorlink {
    my ($dcdom,$rowtype) = @_;
    my $coauthorform=&Apache::loncommon::selectauthor_link('rolechoice',$dcdom);
    my $hiddenitems = '<input type="hidden" name="adhoccauname'.$rowtype.'_'.$dcdom.'" value="" />';
    return $coauthorform.$hiddenitems;
}

sub display_cc_role {
    my $rolekey = shift;
    my ($roletext,$roletext_end);
    my $advanced = $env{'user.adv'};
    my $tryagain = $env{'form.tryagain'};
    unless ($rolekey =~/^error\:/) {
        if ($rolekey =~ m{^user\.role\.(cc|co)\./($match_domain)/($match_courseid)$}) {
            my $ccrole = $1;
            my $tdom = $2;
            my $trest = $3;
            my $tcourseid = $tdom.'_'.$trest;
            my $trolecode = $ccrole.'./'.$tdom.'/'.$trest;
            my $twhere;
            my $ttype;
            my $skipcal;
            my $tbg='LC_roles_is';
            my %newhash=&Apache::lonnet::coursedescription($tcourseid);
            if (%newhash) {
                $twhere=$newhash{'description'}.
                        ' <span class="LC_fontsize_small">'.
                        &Apache::loncommon::syllabuswrapper(&mt('Syllabus'),$trest,$tdom).
                        '</span>';
                $ttype = $newhash{'type'};
            } else {
                $twhere=&mt('Currently not available');
                $env{'course.'.$tcourseid.'.description'}=$twhere;
                $skipcal = 1;
            }
            my $trole = &Apache::lonnet::plaintext($ccrole,$ttype,$tcourseid);
            $twhere.="<br />".&mt('Domain').":".$tdom;
            ($roletext,$roletext_end) = &build_roletext($trolecode,$tdom,$trest,'is',$tryagain,$advanced,'',$tbg,$trole,$twhere,'','','',1,'','','',$skipcal);
        }
    }
    return ($roletext,$roletext_end);
}

sub display_curr_role {
    my ($currentrole) = @_;
    my ($roletext,$roletext_end);
    my $advanced = $env{'user.adv'};
    my $tryagain = $env{'form.tryagain'};
    my ($role,$rest) = split(m{\./},$currentrole,2);
    unless (!defined($role) || $role eq '') {
        if ($rest =~ m{^($match_domain)/($match_courseid)(?:/(\w+)|$)}) {
            my $cdom = $1;
            my $cnum = $2;
            my $csec = $3;
            my $cid = $cdom.'_'.$cnum;
            my $ttype = $env{'course.'.$cid.'.type'};
            my $skipcal = 1;
            my $tbg='LC_roles_is';
            my $twhere = $env{'course.'.$cid.'.description'}. 
                        ' <span class="LC_fontsize_small">'.
                        &Apache::loncommon::syllabuswrapper(&mt('Syllabus'),$cnum,$cdom).
                        '</span>';
            my $trole = &Apache::lonnet::plaintext($role,$ttype,$cid);
            if ($csec) {
                $twhere.= '&nbsp; '.&mt('Section').':&nbsp;'.$csec;
            }
            if ($role ne 'st') {
                $twhere.= '&nbsp; '.&mt('Domain').':&nbsp;'.$cdom;
            }
            ($roletext,$roletext_end) = &build_roletext($currentrole,$cdom,$cnum,'is',$tryagain,$advanced,'',$tbg,$trole,$twhere,'','','',1,'','','',$skipcal);
        }
    }
    return ($roletext,$roletext_end);
}

sub adhoc_roles_row {
    my ($dcdom,$rowtype) = @_;
    my $output = &Apache::loncommon::continue_data_table_row()
                 .' <td colspan="5" class="LC_textsize_mobile">'
                 .&mt('[_1]Ad hoc[_2] roles in domain [_3]'
                     ,'<span class="LC_cusr_emph">','</span>',$dcdom)
                 .' -- ';
    my $role = 'cc';
    my $selectcclink = &courselink($dcdom,$rowtype,$role);
    my $ccrole = &Apache::lonnet::plaintext('co',undef,undef,1);
    my $carole = &Apache::lonnet::plaintext('ca');
    my $selectcalink = &coauthorlink($dcdom,$rowtype);
    $output.=$ccrole.': '.$selectcclink
            .' | '.$carole.': '.$selectcalink.'</td>'
            .&Apache::loncommon::end_data_table_row();
    return $output;
}

sub adhoc_customroles_row {
    my ($role,$dhdom,$rowtype,$update,$then) = @_;
    my $liverole = 1;
    my ($tstart,$tend)=split(/\./,$env{"user.role.$role./$dhdom/"});
    my $limit = $update;
    if (($role eq 'dh') && ($env{'request.role'} eq 'dh./'.$dhdom.'/')) {
        $limit = $then;
    }
    if ($tstart && $tstart>$limit) { $liverole = 0; }
    if ($tend   && $tend  <$limit) { $liverole = 0; }
    return unless ($liverole);
    my %domdefaults = &Apache::lonnet::get_domain_defaults($dhdom); 
    if (ref($domdefaults{'adhocroles'}) eq 'HASH') {
        if (scalar(keys(%{$domdefaults{'adhocroles'}})) > 0) {
            return &Apache::loncommon::continue_data_table_row()
                  .' <td colspan="5" class="LC_textsize_mobile">'
                  .&mt('[_1]Ad hoc[_2] course/community roles in domain [_3]',
                       '<span class="LC_cusr_emph">','</span>',$dhdom)
                  .' -- '.&courselink($dhdom,$rowtype,$role);
        }
    }
    return;
}

sub recent_filename {
    my $area=shift;
    return 'nohist_recent_'.&escape($area);
}

sub courseloadpage {
    my ($courseid) = @_;
    my $startpage;
    my %entry_settings = &Apache::lonnet::get('nohist_whatsnew',
					      [$courseid.':courseinit']);
    my ($tmp) = %entry_settings;
    unless ($tmp =~ /^error: 2 /) {
        $startpage = $entry_settings{$courseid.':courseinit'};
    }
    if ($startpage eq '') {
        if (exists($env{'environment.course_init_display'})) {
            $startpage = $env{'environment.course_init_display'};
        }
    }
    return $startpage;
}

sub update_session_roles {
    my $then=$env{'user.login.time'};
    my $refresh=$env{'user.refresh.time'};
    if (!$refresh) {
        $refresh = $then;
    }
    my $update = $env{'user.update.time'};
    if (!$update) {
        $update = $then;
    }
    my $now = time;
    my %roleshash =
        &Apache::lonnet::get_my_roles('','','userroles',
                                      ['active','future','previous'],
                                      undef,undef,1);
    my ($msg,@newsec,$oldsec,$currrole_expired,@changed_roles,
        %changed_groups,%dbroles,%deletedroles,%allroles,%allgroups,
        %userroles,%checkedgroup,%crprivs,$hasgroups,%rolechange,
        %groupchange,%newrole,%newgroup,%customprivchg,%groups_roles,
        @rolecodes);
    my @possroles = ('cr','st','ta','ad','ep','in','co','cc');
    my %courseroles;
    foreach my $item (keys(%roleshash)) {
        my ($uname,$udom,$role,$remainder) = split(/:/,$item,4);
        my ($tstart,$tend) = split(/:/,$roleshash{$item});
        my ($section,$group,@group_privs);
        if ($role =~ m{^gr/(\w*)$}) {
            $role = 'gr';
            my $priv = $1;
            next if ($tstart eq '-1');
            if (&curr_role_status($tstart,$tend,$refresh,$now) eq 'active') {
                if ($priv ne '') {
                    push(@group_privs,$priv);
                }
            }
            if ($remainder =~ /:/) {
                (my $additional_privs,$group) =
                    ($remainder =~ /^([\w:]+):([^:]+)$/);
                if ($additional_privs ne '') {
                    if (&curr_role_status($tstart,$tend,$refresh,$now) eq 'active') {
                        push(@group_privs,split(/:/,$additional_privs));
                        @group_privs = sort(@group_privs);
                    }
                }
            } else {
                $group = $remainder;
            }
        } else {
            $section = $remainder;
        }
        my $where = "/$udom/$uname";
        if ($section ne '') {
            $where .= "/$section";
        } elsif ($group ne '') {
            $where .= "/$group";
        }
        my $rolekey = "$role.$where";
        my $envkey = "user.role.$rolekey";
        $dbroles{$envkey} = 1;
        if (($env{'request.role'} eq $rolekey) && ($role ne 'st')) {
            if (&curr_role_status($tstart,$tend,$refresh,$now) ne 'active') {
                $currrole_expired = 1;
            }
        }
        if ($env{$envkey} eq '') {
            my $status_in_db =
                &curr_role_status($tstart,$tend,$now,$now);
                &gather_roleprivs(\%allroles,\%allgroups,\%userroles,$where,$role,$tstart,$tend,$status_in_db);
            if (($role eq 'st') && ($env{'request.role'} =~ m{^\Q$role\E\.\Q/$udom/$uname\E})) {
                if ($status_in_db eq 'active') {
                    if ($section eq '') {
                        push(@newsec,'none');
                    } else {
                        push(@newsec,$section);
                    }
                }
            } else {
                unless (grep(/^\Q$role\E$/,@changed_roles)) {
                    push(@changed_roles,$role);
                }
                if ($status_in_db ne 'previous') {
                    if ($role eq 'gr') {
                        $newgroup{$rolekey} = $status_in_db;
                        if ($status_in_db eq 'active') {
                            unless (ref($courseroles{$udom}) eq 'HASH') {
                                %{$courseroles{$udom}} =
                                    &Apache::lonnet::get_my_roles('','','userroles',
                                                                  ['active'],\@possroles,
                                                                  [$udom],1);
                            }
                            &Apache::lonnet::get_groups_roles($udom,$uname,
                                                              $courseroles{$udom},
                                                              \@rolecodes,\%groups_roles);
                        }
                    } else {
                        $newrole{$rolekey} = $status_in_db;
                    }
                }
            }
        } else {
            my ($currstart,$currend) = split(/\./,$env{$envkey});
            if ($role eq 'gr') {
                if (&curr_role_status($currstart,$currend,$refresh,$update) ne 'previous') {
                    $hasgroups = 1;
                }
            }
            if (($currstart ne $tstart) || ($currend ne $tend)) {
                my $status_in_env =
                    &curr_role_status($currstart,$currend,$refresh,$update);
                my $status_in_db =
                    &curr_role_status($tstart,$tend,$now,$now);
                if ($status_in_env ne $status_in_db) {
                    if ($status_in_env eq 'active') {
                        if ($role eq 'st') {
                            if ($env{'request.role'} eq $rolekey) {
                                my $switchsection;
                                unless (ref($courseroles{$udom}) eq 'HASH') {
                                    %{$courseroles{$udom}} =
                                        &Apache::lonnet::get_my_roles('','','userroles',
                                                                      ['active'],
                                                                      \@possroles,[$udom],1);
                                }
                                foreach my $crsrole (keys(%{$courseroles{$udom}})) {
                                    if ($crsrole =~ /^\Q$uname\E:\Q$udom\E:st/) {
                                        $switchsection = 1;
                                        last;
                                    }
                                }
                                if ($switchsection) {
                                    if ($section eq '') {
                                        $oldsec = 'none';
                                    } else {
                                        $oldsec = $section;
                                    }
                                    &gather_roleprivs(\%allroles,\%allgroups,\%userroles,$where,$role,$tstart,$tend,$status_in_db);
                                } else {
                                    $currrole_expired = 1;
                                    next;
                                }
                            }
                        }
                        unless ($rolekey eq $env{'request.role'}) {
                            if ($role eq 'gr') {
                                &Apache::lonnet::delete_env_groupprivs($where,\%courseroles,\@possroles);
                            } else {
                                &Apache::lonnet::delenv("user.priv.$rolekey",undef,[$role]);
                                &Apache::lonnet::delenv("user.priv.cm.$where",undef,['cm']);
                            }
                            &gather_roleprivs(\%allroles,\%allgroups,\%userroles,$where,$role,$tstart,$tend,$status_in_db);
                        }
                    } elsif ($status_in_db eq 'active') {
                        if (($role eq 'st') &&
                            ($env{'request.role'} =~ m{^\Q$role\E\.\Q/$udom/$uname\E})) {
                            if ($section eq '') {
                                push(@newsec,'none');
                            } else {
                                push(@newsec,$section);
                            }
                        } elsif ($role eq 'gr') {
                            unless (ref($courseroles{$udom}) eq 'HASH') {
                                %{$courseroles{$udom}} =
                                    &Apache::lonnet::get_my_roles('','','userroles',
                                                                  ['active'],
                                                                  \@possroles,[$udom],1);
                            }
                            &Apache::lonnet::get_groups_roles($udom,$uname,
                                                              $courseroles{$udom},
                                                              \@rolecodes,\%groups_roles);
                        }
                        &gather_roleprivs(\%allroles,\%allgroups,\%userroles,$where,$role,$tstart,$tend,$status_in_db);
                    }
                    unless (grep(/^\Q$role\E$/,@changed_roles)) {
                        push(@changed_roles,$role);
                    }
                    if ($role eq 'gr') {
                        $groupchange{"/$udom/$uname"}{$group} = $status_in_db;
                    } else {
                        $rolechange{$rolekey} = $status_in_db;
                    }
                }
            } else {
                if ($role eq 'gr') {
                    unless ($checkedgroup{$where}) {
                        my $status_in_db =
                            &curr_role_status($tstart,$tend,$refresh,$now);
                        if ($tstart eq '-1') {
                            $status_in_db = 'deleted';
                        }
                        unless (ref($courseroles{$udom}) eq 'HASH') {
                            %{$courseroles{$udom}} =
                                &Apache::lonnet::get_my_roles('','','userroles',
                                                              ['active'],
                                                              \@possroles,[$udom],1);
                        }
                        if (ref($courseroles{$udom}) eq 'HASH') {
                            foreach my $item (keys(%{$courseroles{$udom}})) {
                                next unless ($item =~ /^\Q$uname\E/);
                                my ($cnum,$cdom,$crsrole,$crssec) = split(/:/,$item);
                                my $area = '/'.$cdom.'/'.$cnum;
                                if ($crssec ne '') {
                                    $area .= '/'.$crssec;
                                }
                                my $crsrolekey = $crsrole.'.'.$area;
                                my $currprivs = $env{'user.priv.'.$crsrole.'.'.$area.'.'.$where};
                                $currprivs =~ s/^://;
                                $currprivs =~ s/\&F$//;
                                my @curr_grp_privs = split(/\&F:/,$currprivs);
                                @curr_grp_privs = sort(@curr_grp_privs);
                                my @diffs;
                                if (@group_privs > 0 || @curr_grp_privs > 0) {
                                    @diffs = &Apache::loncommon::compare_arrays(\@group_privs,\@curr_grp_privs);
                                }
                                if (@diffs == 0) {
                                    last;
                                } else {
                                    unless(grep(/^\Qgr\E$/,@rolecodes)) {
                                        push(@rolecodes,'gr');
                                    }
                                    &gather_roleprivs(\%allroles,\%allgroups,
                                                      \%userroles,$where,$role,
                                                      $tstart,$tend,$status_in_db);
                                    if ($status_in_db eq 'active') {
                                        &Apache::lonnet::get_groups_roles($udom,$uname,
                                                                          $courseroles{$udom},
                                                                          \@rolecodes,\%groups_roles);
                                    }
                                    $changed_groups{$udom.'_'.$uname}{$group} = $status_in_db;
                                    last;
                                }
                            }
                        }
                        $checkedgroup{$where} = 1;
                    }
                } elsif ($role =~ /^cr/) {
                    my $status_in_db =
                        &curr_role_status($tstart,$tend,$refresh,$now);
                    my ($rdummy,$rest) = split(/\//,$role,2);
                    my %currpriv;
                    unless (exists($crprivs{$rest})) {
                        my ($rdomain,$rauthor,$rrole)=split(/\//,$rest);
                        my $homsvr=&Apache::lonnet::homeserver($rauthor,$rdomain);
                        if (&Apache::lonnet::hostname($homsvr) ne '') {
                            my ($rdummy,$roledef)=
                            &Apache::lonnet::get('roles',["rolesdef_$rrole"],
                                                 $rdomain,$rauthor);
                            if (($rdummy ne 'con_lost') && ($roledef ne '')) {
                                my $i = 0;
                                my @scopes = ('sys','dom','crs');
                                my @privs = split(/\_/,$roledef);
                                foreach my $priv (@privs) {
                                    my ($blank,@prv) = split(/:/,$priv);
                                    @prv = map { $_ .= (/\&\w+$/ ? '':'&F') } @prv;
                                    if (@prv) {
                                        $priv = ':'.join(':',sort(@prv));
                                    }
                                    $crprivs{$rest}{$scopes[$i]} = $priv;
                                    $i++;
                                }
                            }
                        }
                    }
                    my $status_in_env =
                        &curr_role_status($currstart,$currend,$refresh,$update);
                    if ($status_in_env eq 'active') {
                        $currpriv{sys} = $env{"user.priv.$rolekey./"};
                        $currpriv{dom} = $env{"user.priv.$rolekey./$udom/"};
                        $currpriv{crs} = $env{"user.priv.$rolekey.$where"};
                        if (keys(%crprivs)) {
                            if (($crprivs{$rest}{sys} ne $currpriv{sys}) ||
                                ($crprivs{$rest}{dom} ne $currpriv{dom})
 ||
                                ($crprivs{$rest}{crs} ne $currpriv{crs})) {
                                &gather_roleprivs(\%allroles,\%allgroups,
                                                  \%userroles,$where,$role,
                                                  $tstart,$tend,$status_in_db);
                                unless (grep(/^\Q$role\E$/,@changed_roles)) {
                                    push(@changed_roles,$role);
                                }
                                $customprivchg{$rolekey} = $status_in_env;
                            }
                        }
                    }
                }
            }
        }
    }
    foreach my $envkey (keys(%env)) {
        next unless ($envkey =~ /^user\.role\./);
        next if ($dbroles{$envkey});
        next if ($envkey eq 'user.role.'.$env{'request.role'});
        my ($currstart,$currend) = split(/\./,$env{$envkey});
        my $status_in_env =
            &curr_role_status($currstart,$currend,$refresh,$update);
        my ($rolekey) = ($envkey =~ /^user\.role\.(.+)$/);
        my ($role,$rest)=split(m{\./},$rolekey,2);
        $rest = '/'.$rest;
        if (&Apache::lonnet::delenv($envkey,undef,[$role])) {
            if ($status_in_env eq 'active') {
                if ($role eq 'gr') {
                    &Apache::lonnet::delete_env_groupprivs($rest,\%courseroles,
                                                           \@possroles);
                } else {
                    &Apache::lonnet::delenv("user.priv.$rolekey",undef,[$role]);
                    &Apache::lonnet::delenv("user.priv.cm.$rest",undef,['cm']);
                }
                unless (grep(/^\Q$role\E$/,@changed_roles)) {
                    push(@changed_roles,$role);
                }
                $deletedroles{$rolekey} = 1;
            }
        }
    }
    if (($oldsec) && (@newsec > 0)) {
        if (@newsec > 1) {
            $msg = '<p class="LC_warning">'.&mt('The section has changed for your current role. Log-out and log-in again to select a role for the new section.').'</p>';
        } else {
            my $newrole = $env{'request.role'};
            if ($newsec[0] eq 'none') {
                $newrole =~ s{(/[^/])$}{};
            } elsif ($oldsec eq 'none') {
                $newrole .= '/'.$newsec[0];
            } else {
                $newrole =~ s{([^/]+)$}{$newsec[0]};
            }
            my $coursedesc = $env{'course.'.$env{'request.course.id'}.'.description'};
            my ($curr_role) = ($env{'request.role'} =~ m{^(\w+)\./$match_domain/$match_courseid});
            my %temp=('logout_'.$env{'request.course.id'} => time);
            &Apache::lonnet::put('email_status',\%temp);
            &Apache::lonnet::delenv('user.state.'.$env{'request.course.id'});
            &Apache::lonnet::appenv({"request.course.id"   => '',
                                     "request.course.fn"   => '',
                                     "request.course.uri"  => '',
                                     "request.course.sec"  => '',
                                     "request.role"        => 'cm',
                                     "request.role.adv"    => $env{'user.adv'},
                                     "request.role.domain" => $env{'user.domain'}});
            my $rolename = &Apache::loncommon::plainname($curr_role);
            $msg = '<p><form name="reselectrole" action="/adm/roles" method="post" />'.
                   '<input type="hidden" name="newrole" value="" />'.
                   '<input type="hidden" name="selectrole" value="1" />'.
                   '<span class="LC_info">'.
                   &mt('Your section has changed for your current [_1] role in [_2].',$rolename,$coursedesc).'</span><br />';
            my $button = '<input type="button" name="sectionchanged" value="'.
                         &mt('Re-Select').'" onclick="javascript:enterrole(this.form,'."'$newrole','sectionchanged'".')" />';
            if ($newsec[0] eq 'none') {
                $msg .= &mt('[_1] to continue with your new section-less role.',$button);
            } else {
                $msg .= &mt('[_1] to continue with your new role in section ([_2]).',$button,$newsec[0]);
            }
            $msg .= '</form></p>';
        }
    } elsif ($currrole_expired) {
        $msg .= '<p class="LC_warning">';
        if (&Apache::loncommon::show_course()) {
            $msg .= &mt('Your role in the current course has expired.');
        } else {
            $msg .= &mt('Your current role has expired.');
        }
        $msg .= '<br />'.&mt('However you can continue to use this role until you logout, click the "Re-Select" button, or your session has been idle for more than 24 hours.').'</p>';
    }
    &Apache::lonnet::set_userprivs(\%userroles,\%allroles,\%allgroups,\%groups_roles);
    my ($curr_is_adv,$curr_role_adv,$curr_author,$curr_role_author);
    $curr_author = $env{'user.author'};
    if (($env{'request.role'} =~/^au/) || ($env{'request.role'} =~/^ca/) ||
        ($env{'request.role'} =~/^aa/)) {
        $curr_role_author=1;
    }
    $curr_is_adv = $env{'user.adv'};
    $curr_role_adv = $env{'request.role.adv'};
    if (keys(%userroles) > 0) {
        foreach my $role (@changed_roles) {
            unless(grep(/^\Q$role\E$/,@rolecodes)) {
                push(@rolecodes,$role);
            }
        }
        unless(grep(/^\Qcm\E$/,@rolecodes)) {
            push(@rolecodes,'cm');
        }
        &Apache::lonnet::appenv(\%userroles,\@rolecodes);
    }
    my %newenv;
    if (&Apache::lonnet::is_advanced_user($env{'user.domain'},$env{'user.name'})) {
        unless ($curr_is_adv) {
            $newenv{'user.adv'} = 1;
        }
    } elsif ($curr_is_adv && !$curr_role_adv) {
        &Apache::lonnet::delenv('user.adv');
    }
    my %authorroleshash =
        &Apache::lonnet::get_my_roles('','','userroles',['active'],['au','ca','aa']);
    if (keys(%authorroleshash)) {
        unless ($curr_author) {
            $newenv{'user.author'} = 1;
        }
    } elsif ($curr_author && !$curr_role_author) {
        &Apache::lonnet::delenv('user.author');
    }
    if ($env{'request.course.id'}) {
        my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
        my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
        my (@activecrsgroups,$crsgroupschanged);
        if ($env{'request.course.groups'}) {
            @activecrsgroups = split(/:/,$env{'request.course.groups'});
            foreach my $item (keys(%deletedroles)) {
                if ($item =~ m{^gr\./\Q$cdom\E/\Q$cnum\E/(\w+)$}) {
                    if (grep(/^\Q$1\E$/,@activecrsgroups)) {
                        $crsgroupschanged = 1;
                        last;
                    }
                }
            }
        }
        unless ($crsgroupschanged) {
            foreach my $item (keys(%newgroup)) {
                if ($item =~ m{^gr\./\Q$cdom\E/\Q$cnum\E/(\w+)$}) {
                    if ($newgroup{$item} eq 'active') {
                        $crsgroupschanged = 1;
                        last;
                    }
                }
            }
        }
        if ((ref($changed_groups{$env{'request.course.id'}}) eq 'HASH') ||
            (ref($groupchange{"/$cdom/$cnum"}) eq 'HASH') ||
            ($crsgroupschanged)) {
            my %grouproles =  &Apache::lonnet::get_my_roles('','','userroles',
                                                            ['active'],['gr'],[$cdom],1);
            my @activegroups;
            foreach my $item (keys(%grouproles)) {
                next unless($item =~ /^\Q$cnum\E:\Q$cdom\E/);
                my $group;
                my ($crsn,$crsd,$role,$remainder) = split(/:/,$item,4);
                if ($remainder =~ /:/) {
                    (my $other,$group) = ($remainder =~ /^([\w:]+):([^:]+)$/);
                } else {
                    $group = $remainder;
                }
                if ($group ne '') {
                    push(@activegroups,$group);
                }
            }
            $newenv{'request.course.groups'} = join(':',@activegroups);
        }
    }
    if (keys(%newenv)) {
        &Apache::lonnet::appenv(\%newenv);
    }
    if (!@changed_roles || !(keys(%changed_groups))) {
        my ($rolesmsg,$groupsmsg);
        if (!@changed_roles) {
            if (&Apache::loncommon::show_course()) {
                $rolesmsg = &mt('No new courses or communities');
            } else {
                $rolesmsg = &mt('No role changes');
            }
        }
        if ($hasgroups && !(keys(%changed_groups)) && !(grep(/gr/,@changed_roles))) {
            $groupsmsg = &mt('No changes in course/community groups');
        }
        if (!@changed_roles && !(keys(%changed_groups))) {
            if (($msg ne '') || ($groupsmsg ne '')) {
                $msg .= '<ul>';
                if ($rolesmsg) {
                    $msg .= '<li>'.$rolesmsg.'</li>';
                }
                if ($groupsmsg) {
                    $msg .= '<li>'.$groupsmsg.'</li>';
                }
                $msg .= '</ul>';
            } else {
                $msg = '&nbsp;<span class="LC_cusr_emph">'.$rolesmsg.'</span><br />';
            }
            return $msg;
        }
    }
    my $changemsg;
    if (@changed_roles > 0) {
        if (keys(%newgroup) > 0) {
            my $groupmsg;
            my (%curr_groups,%groupdescs,$currcrs);
            foreach my $item (sort(keys(%newgroup))) {
                if (&is_active_course($item,$refresh,$update,\%roleshash)) {
                    if ($item =~ m{^gr\./($match_domain/$match_courseid)/(\w+)$}) {
                        my ($cdom,$cnum) = split(/\//,$1);
                        my $group = $2;
                        if ($currcrs ne $cdom.'_'.$cnum) {
                            if ($currcrs) {
                                $groupmsg .= '</ul><li>';
                            }
                            $groupmsg .= '<li><b>'.
                                         $env{'course.'.$cdom.'_'.$cnum.'.description'}.'</b><ul>';
                            $currcrs = $cdom.'_'.$cnum;
                        }
                        my $groupdesc;
                        unless (ref($curr_groups{$cdom.'_'.$cnum}) eq 'HASH') {
                            %{$curr_groups{$cdom.'_'.$cnum}} = 
                                &Apache::longroup::coursegroups($cdom,$cnum);
                        }
                        unless ((ref($groupdescs{$cdom.'_'.$cnum}) eq 'HASH') &&
                            ($groupdescs{$cdom.'_'.$cnum}{$group})) {

                            my %groupinfo = 
                                &Apache::longroup::get_group_settings($curr_groups{$cdom.'_'.$cnum}{$group});
                            $groupdescs{$cdom.'_'.$cnum}{$group} = 
                                &unescape($groupinfo{'description'});
                        }
                        $groupdesc = $groupdescs{$cdom.'_'.$cnum}{$group};
                        if ($groupdesc) {
                            $groupmsg .= '<li>'.
                                         &mt('[_1] with status: [_2].',
                                         '<b>'.$groupdesc.'</b>',$newgroup{$item}).'</li>';
                        }
                    }
                }
                if ($groupmsg) {
                    $groupmsg .= '</ul></li>';
                }
            }
            if ($groupmsg) {
                $changemsg .= '<li>'.
                              &mt('Courses with new groups').'</li>'.
                              '<ul>'.$groupmsg.'</ul></li>';
            }
        }
        if (keys(%newrole) > 0) {
            my $newmsg;
            foreach my $item (sort(keys(%newrole))) {
                my $desc = &role_desc($item,$update,$refresh,$now);
                if ($desc) {
                    $newmsg .= '<li>'.
                               &mt('[_1] with status: [_2].',
                               $desc,&mt($newrole{$item})).'</li>';
                }
            }
            if ($newmsg) {
                $changemsg .= '<li>'.&mt('New roles').
                              '<ul>'.$newmsg.'</ul>'.
                              '</li>';
            }
        }
        if (keys(%customprivchg) > 0) {
            my $privmsg;
            foreach my $item (sort(keys(%customprivchg))) {
                my $desc = &role_desc($item,$update,$refresh,$now);
                if ($desc) {
                    $privmsg .= '<li>'.$desc.'</li>';
                }
            }
            if ($privmsg) {
                $changemsg .= '<li>'.
                              &mt('Custom roles with privilege changes').
                              '<ul>'.$privmsg.'</ul>'.
                              '</li>';
             }
        }
        if (keys(%rolechange) > 0) {
            my $rolemsg;
            foreach my $item (sort(keys(%rolechange))) {
                my $desc = &role_desc($item,$update,$refresh,$now);  
                if ($desc) {
                    $rolemsg .= '<li>'.
                                &mt('[_1] status now: [_2].',$desc,
                                $rolechange{$item}).'</li>';
                }
            }
            if ($rolemsg) {
                $changemsg .= '<li>'.
                              &mt('Existing roles with status changes').'</li>'.
                              '<ul>'.$rolemsg.'</ul>'.
                              '</li>';
            }
        }
        if (keys(%deletedroles) > 0) {
            my $delmsg;
            foreach my $item (sort(keys(%deletedroles))) {
                my $desc = &role_desc($item,$update,$refresh,$now);
                if ($desc) {
                    $delmsg .= '<li>'.$desc.'</li>';
                }
            }
            if ($delmsg) {
                $changemsg .= '<li>'.
                              &mt('Existing roles now expired').'</li>'.
                              '<ul>'.$delmsg.'</ul>'.
                              '</li>';
            }
        }
    }
    if ((keys(%changed_groups) > 0) || (keys(%groupchange) > 0)) {
        my $groupchgmsg;
        foreach my $key (sort(keys(%changed_groups))) {
            my $crs = 'gr/'.$key;
            $crs =~ s/_/\//;
            if (&is_active_course($crs,$refresh,$update,\%roleshash)) {
                if (ref($changed_groups{$key}) eq 'HASH') {
                    my @showgroups;
                    foreach my $group (sort(keys(%{$changed_groups{$key}}))) {
                        if ($changed_groups{$key}{$group} eq 'active') {
                            push(@showgroups,$group);
                        }
                    }
                    if (@showgroups > 0) {
                        $groupchgmsg .= '<li>'.
                                        &mt('Course: [_1], groups: [_2].',$key,
                                        join(', ',@showgroups)).
                                        '</li>';
                    }
                }
            }
        }
        if (keys(%groupchange) > 0) {
            $groupchgmsg .= '<li>'.
                          &mt('Existing course/community groups with status changes').'</li>'.
                          '<ul>';
            foreach my $crs (sort(keys(%groupchange))) {
                my $cid = $crs;
                $cid=~s{^/}{};
                $cid=~s{/}{_};
                my $crsdesc = $env{'course.'.$cid.'.description'};
                my $cdom = $env{'course.'.$cid.'.domain'};
                my $cnum = $env{'course.'.$cid.'.num'};
                my %curr_groups = &Apache::longroup::coursegroups($cdom,$cnum);
                my %groupdesc; 
                if (ref($groupchange{$crs}) eq 'HASH') {
                    $groupchgmsg .= '<li>'.&mt('Course/Community: [_1]','<b>'.$crsdesc.'</b><ul>');
                    foreach my $group (sort(keys(%{$groupchange{$crs}}))) {
                        unless ($groupdesc{$group}) {
                            my %groupinfo = &Apache::longroup::get_group_settings($curr_groups{$group});
                            $groupdesc{$group} =  &unescape($groupinfo{'description'});
                        }
                        $groupchgmsg .= '<li>'.&mt('Group: [_1] status now: [_2].','<b>'.$groupdesc{$group}.'</b>',$groupchange{$crs}{$group}).'</li>';
                    }
                    $groupchgmsg .= '</ul></li>';
                }
            }
            $groupchgmsg .= '</ul></li>';
        }
        if ($groupchgmsg) {
            $changemsg .= '<li>'.
                          &mt('Courses with changes in groups').'</li>'.
                          '<ul>'.$groupchgmsg.'</ul></li>';
        }
    }
    if ($changemsg) {
        $msg .= '<ul>'.$changemsg.'</ul>';
    } else {
        if (&Apache::loncommon::show_course()) {
            $msg = &mt('No new courses or communities');
        } else {
            $msg = &mt('No role changes');
        }
    }
    return $msg;
}

sub role_desc {
    my ($item,$update,$refresh,$now) = @_;
    my ($where,$trolecode,$role,$tstatus,$tend,$tstart,$twhere,
        $trole,$tremark);
    &Apache::lonnet::role_status('user.role.'.$item,$update,$refresh,
                                 $now,\$role,\$where,\$trolecode,
                                 \$tstatus,\$tstart,\$tend);
    return unless ($role);
    if ($role =~ /^cr\//) {
        my ($rdummy,$rdomain,$rauthor,$rrole)=split(/\//,$role);
        $tremark = &mt('Custom role defined by [_1].',$rauthor.':'.$rdomain);
    }
    $trole=Apache::lonnet::plaintext($role);
    my ($tdom,$trest,$tsection)=
        split(/\//,Apache::lonnet::declutter($where));
    if (($role eq 'ca') || ($role eq 'aa')) {
        my $home = &Apache::lonnet::homeserver($trest,$tdom);
        $home = &Apache::lonnet::hostname($home);
        $twhere=&mt('User').':&nbsp;'.$trest.'&nbsp; '.&mt('Domain').
                ':&nbsp;'.$tdom.'&nbsp; '.&mt('Server').':&nbsp;'.$home;
    } elsif ($role eq 'au') {
        my $home = &Apache::lonnet::homeserver
                       ($env{'user.name'},$env{'user.domain'});
        $home = &Apache::lonnet::hostname($home);
        $twhere=&mt('Domain').':&nbsp;'.$tdom.'&nbsp; '.&mt('Server').
                        ':&nbsp;'.$home;
    } elsif ($trest) {
        my $tcourseid=$tdom.'_'.$trest;
        my $crstype = &Apache::loncommon::course_type($tcourseid);
        $trole = &Apache::lonnet::plaintext($role,$crstype,$tcourseid);
        if ($env{'course.'.$tcourseid.'.description'}) {
            $twhere=$env{'course.'.$tcourseid.'.description'};
        } else {
            my %newhash=&Apache::lonnet::coursedescription($tcourseid);
            if (%newhash) {
                $twhere=$newhash{'description'};
            } else {
                $twhere=&mt('Currently not available');
            }
        }
        if ($tsection) {
            $twhere.= '&nbsp; '.&mt('Section').':&nbsp;'.$tsection;
        }
        if ($role ne 'st') {
            $twhere.= '&nbsp; '.&mt('Domain').':&nbsp;'.$tdom;
        }
    } elsif ($tdom) {
        $twhere = &mt('Domain').':&nbsp;'.$tdom;
    }
    my $output;
    if ($trole) {
        $output = $trole;
        if ($twhere) {
            $output .= " -- $twhere";
        }
        if ($tremark) {
            $output .= '<br />'.$tremark;
        }
    }
    return $output;
}

sub curr_role_status {
    my ($start,$end,$refresh,$update) = @_;
    if (($start) && ($start<0)) { return 'deleted' };
    my $status = 'active';
    if (($end) && ($end<=$update)) {
        $status = 'previous';
    }
    if (($start) && ($refresh<$start)) {
        $status = 'future';
    }
    return $status;
}

sub gather_roleprivs {
    my ($allroles,$allgroups,$userroles,$area,$role,$tstart,$tend,$status) = @_;
    return unless ((ref($allroles) eq 'HASH') && (ref($allgroups) eq 'HASH') && (ref($userroles) eq 'HASH'));
    if (($area ne '') && ($role ne '')) {
        &Apache::lonnet::userrolelog($role,$env{'user.name'},$env{'user.domain'},
                                     $area,$tstart,$tend);
        my $spec=$role.'.'.$area;
        $userroles->{'user.role.'.$spec} = $tstart.'.'.$tend;
        my ($tdummy,$tdomain,$trest)=split(/\//,$area);
        if ($status eq 'active') { 
            if ($role =~ /^cr\//) {
                &Apache::lonnet::custom_roleprivs($allroles,$role,$tdomain,$trest,$spec,$area);
            } elsif ($role eq 'gr') {
                my %rolehash = &Apache::lonnet::get('roles',[$area.'_'.$role],
                                                    $env{'user.domain'},
                                                    $env{'user.name'});
                my ($trole) = split(/_/,$rolehash{$area.'_'.$role},2);
                (undef,my $group_privs) = split(/\//,$trole);
                $group_privs = &unescape($group_privs);
                &Apache::lonnet::group_roleprivs($allgroups,$area,$group_privs,$tend,$tstart);
            } else {
                &Apache::lonnet::standard_roleprivs($allroles,$role,$tdomain,$spec,$trest,$area);
            }
        }
    }
    return;
}

sub is_active_course {
    my ($rolekey,$refresh,$update,$roleshashref) = @_;
    return unless(ref($roleshashref) eq 'HASH');
    my ($role,$cdom,$cnum) = split(/\//,$rolekey);
    my $is_active;
    foreach my $key (keys(%{$roleshashref})) {
        if ($key =~ /^\Q$cnum\E:\Q$cdom\E:/) {
            my ($tstart,$tend) = split(/:/,$roleshashref->{$key});
            my $status = &curr_role_status($tstart,$tend,$refresh,$update);
            if ($status eq 'active') {
                $is_active = 1;
                last;
            }
        }
    }
    return $is_active;
}

sub get_roles_functions {
    my ($rolescount,$cattype) = @_;
    my @links;
    push(@links,["javascript:rolesView('doupdate');",'start-here-22x22',&mt('Check for changes')]);
    if ($env{'environment.canrequest.author'}) {
        unless (&Apache::loncoursequeueadmin::is_active_author()) {
            push(@links,["javascript:rolesView('requestauthor');",'list-add-22x22',&mt('Request author role')]);
        }
    }
    if (($rolescount > 3) || ($env{'environment.recentroles'})) {
        push(@links,['/adm/preferences?action=changerolespref&amp;returnurl=/adm/roles','role_hotlist-22x22',&mt('Hotlist')]);
    }
    if (&Apache::lonmenu::check_for_rcrs()) {
        push(@links,['/adm/requestcourse','rcrs-22x22',&mt('Request course')]);
    }
    if ($env{'form.state'} eq 'queued') {
        push(@links,["javascript:rolesView('noqueued');",'selfenrl-queue-22x22',&mt('Hide queued')]);
    } else {
        push(@links,["javascript:rolesView('queued');",'selfenrl-queue-22x22',&mt('Show queued')]);
    }
    if ($env{'user.adv'}) {
        if ($env{'form.display'} eq 'showall') {
            push(@links,["javascript:rolesView('noshowall');",'edit-redo-22x22',&mt('Exclude expired')]);
        } else {
            push(@links,["javascript:rolesView('showall');",'edit-undo-22x22',&mt('Include expired')]);
        }
    }
    unless ($cattype eq 'none') {
        push(@links,['/adm/coursecatalog','ccat-22x22',&mt('Course catalog')]);
    }
    my $funcs;
    if ($env{'browser.mobile'}) {
        my @functions;
        foreach my $link (@links) {
            push(@functions,[$link->[0],$link->[2]]);
        }
        my $title = 'Display options';
        if ($env{'user.adv'}) {
            $title = 'Roles options';
        }
        $funcs = &Apache::lonmenu::create_submenu('','',$title,\@functions,1,'LC_breadcrumbs_hoverable');
        $funcs = '<ol class="LC_primary_menu LC_floatright">'.$funcs.'</ol>';
    } else {
        $funcs = &Apache::lonhtmlcommon::start_funclist();
        foreach my $link (@links) {
            $funcs .= &Apache::lonhtmlcommon::add_item_funclist(
                          '<a href="'.$link->[0].'" class="LC_menubuttons_link">'.
                          '<img src="/res/adm/pages/'.$link->[1].'.png" class="LC_icon" alt="'.$link->[2].'" />'.
                          $link->[2].'</a>');
        }
        $funcs .= &Apache::lonhtmlcommon::end_funclist();
        $funcs = &Apache::loncommon::head_subbox($funcs);
    }
    return $funcs;
}

sub get_queued {
    my ($output,%reqcrs);
    my ($types,$typenames) = &Apache::loncommon::course_types();
    my %statusinfo = &Apache::lonnet::dump('courserequests',$env{'user.domain'},
                                           $env{'user.name'},'^status:');
    foreach my $key (keys(%statusinfo)) {
        next unless (($statusinfo{$key} eq 'approval') || ($statusinfo{$key} eq 'pending'));
        (undef,my($cdom,$cnum)) = split(/:/,$key);
        my $requestkey = $cdom.'_'.$cnum;
        if ($requestkey =~ /^($match_domain)_($match_courseid)$/) {
            my %history = &Apache::lonnet::restore($requestkey,'courserequests',
                                                   $env{'user.domain'},$env{'user.name'});
            next if ((exists($history{'status'})) && ($history{'status'} eq 'created'));
            my $reqtime = $history{'reqtime'};
            my $lastupdate = $history{'timestamp'};
            my $showtype = $history{'crstype'};
            if (defined($typenames->{$history{'crstype'}})) {
                $showtype = $typenames->{$history{'crstype'}};
            }
            my $description;
            if (ref($history{'details'}) eq 'HASH') {
                $description = $history{details}{'cdescr'};
            }
            @{$reqcrs{$reqtime}} = ($description,$showtype); 
        }
    }
    my @sortedtimes = sort {$a <=> $b} (keys(%reqcrs));
    if (@sortedtimes > 0) {
        $output .= '<p><b>'.&mt('Course/Community requests').'</b><br />'.
                   &Apache::loncommon::start_data_table().
                   &Apache::loncommon::start_data_table_header_row().
                   '<th>'.&mt('Date requested').'</th>'.
                   '<th>'.&mt('Course title').'</th>'.
                   '<th>'.&mt('Course type').'</th>';
                   &Apache::loncommon::end_data_table_header_row();
        foreach my $reqtime (@sortedtimes) {
            next unless (ref($reqcrs{$reqtime}) eq 'ARRAY');
            $output .= &Apache::loncommon::start_data_table_row().
                       '<td>'.&Apache::lonlocal::locallocaltime($reqtime).'</td>'.
                       '<td>'.join('</td><td>',@{$reqcrs{$reqtime}}).'</td>'.
                       &Apache::loncommon::end_data_table_row();
        }
        $output .= &Apache::loncommon::end_data_table().
                   '<br /></p>';
    }
    my $queuedselfenroll = &Apache::loncoursequeueadmin::queued_selfenrollment(1);
    if ($queuedselfenroll) {
        $output .= '<p><b>'.&mt('Enrollment requests').'</b><br />'.
                   $queuedselfenroll.'<br /></p>';
    }
    if ($env{'environment.canrequest.author'}) {
        unless (&Apache::loncoursequeueadmin::is_active_author()) {
            my $requestauthor;
            my ($status,$timestamp) = split(/:/,$env{'environment.requestauthorqueued'});
            if (($status eq 'approval') || ($status eq 'approved')) {
                $output .= '<p><b>'.&mt('Author role request').'</b><br />';
                if ($status eq 'approval') {
                    $output .= &mt('A request for Authoring Space submitted on [_1] is awaiting approval',
                                  &Apache::lonlocal::locallocaltime($timestamp));
                } elsif ($status eq 'approved') {
                    my %roleshash =
                        &Apache::lonnet::get_my_roles($env{'user.name'},$env{'user.domain'},'userroles',
                                                      ['active'],['au'],[$env{'user.domain'}]);
                    if (keys(%roleshash)) {
                        $output .= '<span class="LC_info">'.
                                   &mt('Your request for an author role has been approved.').'<br />'.
                                   &mt('Use the "Check for changes" link to update your list of roles.').
                                   '</span>';
                    }
                }
                $output .= '</p>';
            }
        }
    }
    unless ($output) {
        if ($env{'environment.canrequest.author'} || $env{'environment.canrequest.official'} ||
            $env{'environment.canrequest.unofficial'} || $env{'environment.canrequest.community'}) {
            $output = &mt('No requests for courses, communities or authoring currently queued');
        } else {
            $output = &mt('No enrollment requests currently queued awaiting approval');
        }
    }
    return '<div class="LC_left_float"><fieldset><legend>'.&mt('Queued requests').'</legend>'.
           $output.'</fieldset></div><br clear="all" />';
}

sub process_lti {
    my ($r,$cdom,$cnum) = @_;
    my %lti = &Apache::lonnet::get_domain_lti($cdom,'provider');
    my $uriscope = &LONCAPA::ltiutils::lti_provider_scope($env{'request.lti.uri'},
                                                          $cdom,$cnum);
    my $lonhost = $r->dir_config('lonHostID');
    my $internet_names = &Apache::lonnet::get_internet_names($lonhost);
    if ($env{'request.lti.rosterid'} &&
        $env{'request.lti.rosterurl'}) {
        if (ref($lti{$env{'request.lti.login'}}) eq 'HASH') {
            if ($lti{$env{'request.lti.login'}}{'roster'}) {
                my @lcroles = ('in','ta','ep','st');
                my @possibleroles;
                foreach my $role (@lcroles) {
                    if (&Apache::lonnet::allowed('c'.$role,"$cdom/$cnum")) {
                        push(@possibleroles,$role);
                    }
                }
                my $owner = $env{'course.'.$cdom.'_'.$cnum.'.internal.courseowner'};
                if ($owner eq $env{'user.name'}.':'.$env{'user.domain'}) {
                    my $crstype = &Apache::loncommon::course_type($cdom.'_'.$cnum);
                    if ($crstype eq 'Community') {
                        unshift(@possibleroles,'co');
                    } else {
                        unshift(@possibleroles,'cc');
                    }
                }
                if (@possibleroles) {
                    push(@{$rosterupdates},{cid        => $cdom.'_'.$cnum,
                                            lti        => $env{'request.lti.login'},
                                            ltiref     => $lti{$env{'request.lti.login'}},
                                            id         => $env{'request.lti.rosterid'},
                                            url        => $env{'request.lti.rosterurl'},
                                            sourcecrs  => $env{'request.lti.sourcecrs'},
                                            uriscope   => $uriscope,
                                            possroles  => \@possibleroles,
                                            intdoms    => $internet_names,
                                           });
                    unless ($registered_cleanup) {
                        my $handlers = $r->get_handlers('PerlCleanupHandler');
                        $r->set_handlers('PerlCleanupHandler' =>
                                         [\&ltienroll,@{$handlers}]);
                        $registered_cleanup=1;
                    }
                }
            }
        }
    }
    if ($env{'request.lti.passbackid'} &&
        $env{'request.lti.passbackurl'}) {
        if (ref($lti{$env{'request.lti.login'}}) eq 'HASH') {
            if ($lti{$env{'request.lti.login'}}{'passback'}) {
                my ($pbnum,$error) =
                    &LONCAPA::ltiutils::store_passbackurl($env{'request.lti.login'},
                                                          $env{'request.lti.passbackurl'},
                                                          $cdom,$cnum);
                if ($pbnum eq '') {
                    $pbnum = $env{'request.lti.passbackurl'};
                }
                &Apache::lonnet::put('nohist_'.$cdom.'_'.$cnum.'_passback',
                                     {"$uriscope\0$env{'request.lti.sourcecrs'}\0$env{'request.lti.login'}" =>
                                     "$pbnum\0$env{'request.lti.passbackid'}"});
            }
        }
    }
    return;
}

sub ltienroll {
    if (ref($rosterupdates) eq 'ARRAY') {
        foreach my $item (@{$rosterupdates}) {
            if (ref($item) eq 'HASH') {
                &LONCAPA::ltiutils::batchaddroster($item);
            }
        }
    }
}

1;
__END__

=head1 NAME

Apache::lonroles - User Roles Screen

=head1 SYNOPSIS

Invoked by /etc/httpd/conf/srm.conf:

 <Location /adm/roles>
 PerlAccessHandler       Apache::lonacc
 SetHandler perl-script
 PerlHandler Apache::lonroles
 ErrorDocument     403 /adm/login
 ErrorDocument	  500 /adm/errorhandler
 </Location>

=head1 OVERVIEW

=head2 Choosing Roles

C<lonroles> is a handler that allows a user to switch roles in
mid-session. LON-CAPA attempts to work with "No Role Specified", the
default role that a user has before selecting a role, as widely as
possible, but certain handlers for example need specification which
course they should act on, etc. Both in this scenario, and when the
handler determines via C<lonnet>'s C<&allowed> function that a certain
action is not allowed, C<lonroles> is used as error handler. This
allows the user to select another role which may have permission to do
what they were trying to do.

=begin latex

\begin{figure}
\begin{center}
\includegraphics[width=0.45\paperwidth,keepaspectratio]{Sample_Roles_Screen}
  \caption{\label{Sample_Roles_Screen}Sample Roles Screen} 
\end{center}
\end{figure}

=end latex

=head2 Role Initialization

The privileges for a user are established at login time and stored in the session environment. As a consequence, a new role does not become active till the next login. Handlers are able to query for privileges using C<lonnet>'s C<&allowed> function. When a user first logs in, their role is the "common" role, which means that they have the sum of all of their privileges. During a session it might become necessary to choose a particular role, which as a consequence also limits the user to only the privileges in that particular role.

=head1 INTRODUCTION

This module enables a user to select what role he wishes to
operate under (instructor, student, teaching assistant, course
coordinator, etc).  These roles are pre-established by the actions
of upper-level users.

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

=head1 HANDLER SUBROUTINE

This routine is called by Apache and mod_perl.

=over 4

=item *

Roles Initialization (yes/no)

=item *

Get Error Message from Environment

=item *

Who is this?

=item *

Generate Page Output

=item *

Choice or no choice

=item *

Table

=item *

Privileges

=back

=cut