#!/usr/bin/perl

# The LearningOnline Network
#
# expire_DC_role.pl - Expire domain coordinator role from
# a user who currently has such a role in a domain for which current server is
# a library server for the domain.
# 
# $Id: expire_DC_role.pl,v 1.2 2011/03/28 21:16:08 raeburn Exp $
#
# 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

expire_DC_role.pl - Expire domain coordinator role.

=head1 SYNOPSIS

To be run by root from the command line to expire domain coordinator role 
for a user who currently has such a role in a domain for which current 
server is a library server for the domain.

User's homeserver must be the library server where the script is run.

=head1 DESCRIPTION

Carries out steps required for domain coordinator role expiration.

=over 4

=item * 

Tests to see if user already exists for LON-CAPA, if not it aborts. 

=item *

Modify roles.hist and roles.db for user and nohist_domainroles.db for domain.

=back

=cut

# ---------------------------------------------------- Configure general values

use lib '/home/httpd/lib/perl/';
use LONCAPA;
use Apache::lonnet;
use Apache::loncommon;
use Apache::lonlocal();

=pod

=head1 OPTIONS

There are no flags to this script.

usage: expire_DC_role.pl [USERNAME:DOMAIN] [DC ROLEDOMAIN]

The first argument specifies the user name and domain of an existing user
who has a Domain Coordinator role in the "DC ROLEDOMAIN".

The second argument specifies the domain for which the role is to be expired. 

=cut

my ($user,$role_domain) = (@ARGV);
my $lang = &Apache::lonlocal::choose_language();
&Apache::lonlocal::get_language_handle(undef,$lang);

if ($< != 0) { # Am I root?
    print(&mt('You must be root in order to expire a domain coordinator role.').
          "\n");
    exit;
}
# ----------------------------------------------- So, are we invoked correctly?
# Two arguments or abort
if (@ARGV!=2) {
    print(&mt('usage: [_1]','expire_DC_role.pl [USERNAME:DOMAIN] [DC ROLEDOMAIN]').
	"\n");
    exit;
}
my ($user,$role_domain)=(@ARGV);
my ($username,$domain)=split(':',$user);
if (!grep(/^\Q$role_domain\E$/,&Apache::lonnet::current_machine_domains())) {
    print(&mt('**** ERROR **** Domain [_1] is not a domain for which this server is a library server.',$role_domain)."\n");
    exit;
}

my $udpath=&propath($domain,$username);
if (!-d $udpath) {
    print(&mt('**** ERROR **** [_1] is not a LON-CAPA user for which this is the homeserver.',$user)."\n");
    exit;
}

use GDBM_File; # A simple key-value pairing database.

my $rolesref=&LONCAPA::locking_hash_tie("$udpath/roles.db",&GDBM_WRCREAT());
if (!$rolesref) {
    print(&mt('unable to tie [_1]',"roles db: $udpath/roles.db")."\n");
    exit;
}
my ($start,$status,$now);
$now = time();
if (exists($rolesref->{'/'.$role_domain.'/_dc'})) {
    (my $role,my $end,$start) = split('_',$rolesref->{'/'.$role_domain.'/_dc'});
    print(&mt("Confirmed: [_1] has a DC role for domain: [_2].",
	      $user,$role_domain)."\n");
    if ($start) {
	print(&mt("Start date: [_1]",&Apache::lonlocal::locallocaltime($start)).
	      "\n");
	if (!$end) {
	    print(&mt("No planned end date. Proceeding to expire role.")."\n");
            $status = 'active';
	} else {
            print(&mt("End date: [_1]",&Apache::lonlocal::locallocaltime($end)).
                  "\n");
            if (($start <= $now) && ($end > $now)) {
	        print(&mt("Role is currently active. Proceeding to expire role.")."\n");
                $status = 'active';
            } elsif (($start > $now) && ($end >= $start)) {
                print(&mt("Role is currently inactive, but will become active in the future. Proceeding to expire role.")."\n");
                $status = 'future';
            }
        }
    } elsif ($end) {
	print(&mt("End date: [_1]",&Apache::lonlocal::locallocaltime($end)).
	      "\n");
	if ($end >= $now) {
	    print(&mt("Role is currently active. Proceeding to expire role.")."\n");
            $status = 'active';
	}
    }
    if (!$start and !$end) {
	print(&mt("Role is currently active. Proceeding to expire role.")."\n");
        $status = 'active';
    }
    if ($status eq '') {
        print(&mt("Role inactive and will remain so. Expiration is not required.")."\n");
    }
} else {
    print(&mt("[_1] does NOT have a DC role for domain: [_2].",
              $user,$role_domain)."\n".
          &mt("Expiration is not required")."\n");
}

if ($status eq '') {
    &LONCAPA::locking_hash_untie($rolesref);
    exit(0);
}

$rolesref->{'/'.$role_domain.'/_dc'}='dc_'.$now.'_'.$start; # Expire the domain coordinator role.
open(OUT, ">$udpath/roles.hist"); # roles.hist is the synchronous plain text.
foreach my $key (keys(%{$rolesref})) {
    print(OUT $key.' : '.$rolesref->{$key}."\n");
}
close(OUT);
&LONCAPA::locking_hash_untie($rolesref);

`chown www:www $udpath/roles.hist`; # Must be writeable by httpd process.
`chown www:www $udpath/roles.db`; # Must be writeable by httpd process.

my %perlvar = %{&LONCAPA::Configuration::read_conf('loncapa.conf')};
my $dompath = $perlvar{'lonUsersDir'}.'/'.$domain;
my $domrolesref = &LONCAPA::locking_hash_tie("$dompath/nohist_domainroles.db",&GDBM_WRCREAT());

if (!$domrolesref) {
    print(&mt('unable to tie [_1]',"nohist_domainroles db: $dompath/nohist_domainroles.db")."\n");
    exit;
}

# Store in nohist_domainroles.db
my $domkey=&LONCAPA::escape('dc:'.$username.':'.$domain.'::'.$domain.':');
$domrolesref->{$domkey}= &LONCAPA::escape('$now:'.$start);
&LONCAPA::locking_hash_untie($domrolesref);

 system('/bin/chown',"www:www","$dompath/nohist_domainroles.db"); # Must be writeable by httpd process.
 system('/bin/chown',"www:www","$dompath/nohist_domainroles.db.lock");

# Output success message.
print(&mt('User: [_1], domain coordinator role expired in domain: [_2].',$user,$role_domain)."\n");

exit;