# The LearningOnline Network with CAPA
# Handler for requesting to have slots added to a students record
#
# $Id: slotrequest.pm,v 1.79 2007/04/11 21:49:02 albertel Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# LON-CAPA is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#
###

package Apache::slotrequest;

use strict;
use Apache::Constants qw(:common :http :methods);
use Apache::loncommon();
use Apache::lonlocal;
use Apache::lonnet;
use Apache::lonnavmaps();
use Date::Manip;
use lib '/home/httpd/lib/perl/';
use LONCAPA;

sub fail {
    my ($r,$code)=@_;
    if ($code eq 'not_valid') {
	$r->print('<p>'.&mt('Unable to understand what resource you wanted to sign up for.').'</p>');
    } elsif ($code eq 'not_available') {
	$r->print('<p>'.&mt('No slots are available.').'</p>');
    } elsif ($code eq 'not_allowed') {
	$r->print('<p>'.&mt('Not allowed to sign up or change reservations at this time.').'</p>');
    } else {
	$r->print('<p>'.&mt('Failed.').'</p>');
    }
    
    &return_link($r);
    &end_page($r);
}

sub start_page {
    my ($r,$title)=@_;
    $r->print(&Apache::loncommon::start_page($title));
}

sub end_page {
    my ($r)=@_;
    $r->print(&Apache::loncommon::end_page());
}

=pod

 slot_reservations db
   - keys are 
    - slotname\0id -> value is an hashref of
                         name -> user@domain of holder
                         timestamp -> timestamp of reservation
                         symb -> symb of resource that it is reserved for

=cut

sub get_course {
    (undef,my $courseid)=&Apache::lonnet::whichuser();
    my $cdom=$env{'course.'.$courseid.'.domain'};
    my $cnum=$env{'course.'.$courseid.'.num'};
    return ($cnum,$cdom);
}

sub get_reservation_ids {
    my ($slot_name)=@_;
    
    my ($cnum,$cdom)=&get_course();

    my %consumed=&Apache::lonnet::dump('slot_reservations',$cdom,$cnum,
				       "^$slot_name\0");
    if (&Apache::lonnet::error(%consumed)) { 
	return 'error: Unable to determine current status';
    }
    my ($tmp)=%consumed;
    if ($tmp=~/^error: 2 / ) {
	return 0;
    }
    return keys(%consumed);
}

sub space_available {
    my ($slot_name,$slot)=@_;
    my $max=$slot->{'maxspace'};

    if (!defined($max)) { return 1; }

    my $consumed=scalar(&get_reservation_ids($slot_name));
    if ($consumed < $max) {
	return 1
    }
    return 0;
}

sub check_for_reservation {
    my ($symb,$mode)=@_;
    my $student = &Apache::lonnet::EXT("resource.0.availablestudent", $symb,
				       $env{'user.domain'}, $env{'user.name'});

    my $course = &Apache::lonnet::EXT("resource.0.available", $symb,
				    $env{'user.domain'}, $env{'user.name'});
    my @slots = (split(/:/,$student), split(/:/, $course));

    &Apache::lonxml::debug(" slot list is ".join(':',@slots));

    my ($cnum,$cdom)=&get_course();
    my %slots=&Apache::lonnet::get('slots', [@slots], $cdom, $cnum);

    if (&Apache::lonnet::error($student) 
	|| &Apache::lonnet::error($course)
	|| &Apache::lonnet::error(%slots)) {
	return 'error: Unable to determine current status';
    }    
    my @got;
    foreach my $slot_name (sort {
	if (ref($slots{$a}) && ref($slots{$b})) {
	    return $slots{$a}{'starttime'} <=> $slots{$b}{'starttime'}
	}
	if (ref($slots{$a})) { return -1;}
	if (ref($slots{$b})) { return 1;}
	return 0;
    } @slots) {
	next if (!defined($slots{$slot_name}) ||
		 !ref($slots{$slot_name}));
	&Apache::lonxml::debug(time." $slot_name ".
			       $slots{$slot_name}->{'starttime'}." -- ".
			       $slots{$slot_name}->{'startreserve'});
	if ($slots{$slot_name}->{'endtime'} > time &&
	    $slots{$slot_name}->{'startreserve'} < time) {
	    # between start of reservation times and end of slot
	    if ($mode eq 'allslots') {
		push(@got,$slot_name);
	    } else {
		return($slot_name, $slots{$slot_name});
	    }
	}
    }
    if ($mode eq 'allslots' && @got) {
	return @got;
    }
    return (undef,undef);
}

sub get_consumed_uniqueperiods {
    my ($slots) = @_;
    my $navmap=Apache::lonnavmaps::navmap->new;
    my @problems = $navmap->retrieveResources(undef,
					      sub { $_[0]->is_problem() },1,0);
    my %used_slots;
    foreach my $problem (@problems) {
	my $symb = $problem->symb();
	my $student = &Apache::lonnet::EXT("resource.0.availablestudent",
					   $symb, $env{'user.domain'},
					   $env{'user.name'});
	my $course =  &Apache::lonnet::EXT("resource.0.available",
					   $symb, $env{'user.domain'},
					   $env{'user.name'});
	if (&Apache::lonnet::error($student) 
	    || &Apache::lonnet::error($course)) {
	    return 'error: Unable to determine current status';
	}
	foreach my $slot (split(/:/,$student), split(/:/, $course)) {
	    $used_slots{$slot}=1;
	}
    }

    if (!ref($slots)) {
	my ($cnum,$cdom)=&get_course();
	my %slots=&Apache::lonnet::get('slots', [keys(%used_slots)], $cdom, $cnum);
	if (&Apache::lonnet::error(%slots)) {
	    return 'error: Unable to determine current status';
	}
	$slots = \%slots;
    }

    my %consumed_uniqueperiods;
    foreach my $slot_name (keys(%used_slots)) {
	next if (!defined($slots->{$slot_name}) ||
		 !ref($slots->{$slot_name}));
	
        next if (!defined($slots->{$slot_name}{'uniqueperiod'}) ||
		 !ref($slots->{$slot_name}{'uniqueperiod'}));
	$consumed_uniqueperiods{$slot_name} = 
	    $slots->{$slot_name}{'uniqueperiod'};
    }
    return \%consumed_uniqueperiods;
}

sub check_for_conflict {
    my ($symb,$new_slot_name,$new_slot,$slots,$consumed_uniqueperiods)=@_;

    if (!defined($new_slot->{'uniqueperiod'})) { return undef; }

    if (!ref($consumed_uniqueperiods)) {
	$consumed_uniqueperiods = &get_consumed_uniqueperiods($slots);
	if (&Apache::lonnet::error(%$consumed_uniqueperiods)) {
	    return 'error: Unable to determine current status';
	}
    }
    
    my ($new_uniq_start,$new_uniq_end) = @{$new_slot->{'uniqueperiod'}};
    foreach my $slot_name (keys(%$consumed_uniqueperiods)) {
	my ($start,$end)=@{$consumed_uniqueperiods->{$slot_name}};
	if (!
	    ($start < $new_uniq_start &&  $end < $new_uniq_start) ||
	    ($start > $new_uniq_end   &&  $end > $new_uniq_end  )) {
	    return $slot_name;
	}
    }
    return undef;

}

sub make_reservation {
    my ($slot_name,$slot,$symb)=@_;

    my ($cnum,$cdom)=&get_course();

    my $value=&Apache::lonnet::EXT("resource.0.availablestudent",$symb,
				   $env{'user.domain'},$env{'user.name'});
    &Apache::lonxml::debug("value is  $value<br />");

    my $use_slots = &Apache::lonnet::EXT("resource.0.useslots");
    &Apache::lonxml::debug("use_slots is  $use_slots<br />");

    if (&Apache::lonnet::error($value) 
	|| &Apache::lonnet::error($use_slots)) { 
	return 'error: Unable to determine current status';
    }

    my $parm_symb  = $symb;
    my $parm_level = 1;
    if ($use_slots eq 'map' || $use_slots eq 'map_map') {
	my ($map) = &Apache::lonnet::decode_symb($symb);
	$parm_symb = &Apache::lonnet::symbread($map);
	$parm_level = 2;
    }

    foreach my $other_slot (split(/:/, $value)) {
	if ($other_slot eq $slot_name) {
	    my %consumed=&Apache::lonnet::dump('slot_reservations', $cdom,
					       $cnum, "^$slot_name\0");   
	    if (&Apache::lonnet::error($value)) { 
		return 'error: Unable to determine current status';
	    }
	    my $me=$env{'user.name'}.':'.$env{'user.domain'};
	    foreach my $key (keys(%consumed)) {
		if ($consumed{$key}->{'name'} eq $me) {
		    my $num=(split('\0',$key))[1];
		    return -$num;
		}
	    }
	}
    }

    my $max=$slot->{'maxspace'};
    if (!defined($max)) { $max=99999; }

    my (@ids)=&get_reservation_ids($slot_name);
    if (&Apache::lonnet::error(@ids)) { 
	return 'error: Unable to determine current status';
    }
    my $last=0;
    foreach my $id (@ids) {
	my $num=(split('\0',$id))[1];
	if ($num > $last) { $last=$num; }
    }
    
    my $wanted=$last+1;
    &Apache::lonxml::debug("wanted $wanted<br />");
    if (scalar(@ids) >= $max) {
	# full up
	return undef;
    }
    
    my %reservation=('name'      => $env{'user.name'}.':'.$env{'user.domain'},
		     'timestamp' => time,
		     'symb'      => $parm_symb);

    my $success=&Apache::lonnet::newput('slot_reservations',
					{"$slot_name\0$wanted" =>
					     \%reservation},
					$cdom, $cnum);

    if ($success eq 'ok') {
	my $new_value=$slot_name;
	if ($value) {
	    $new_value=$value.':'.$new_value;
	}
	my $result=&Apache::lonparmset::storeparm_by_symb($symb,
						      '0_availablestudent',
						       $parm_level, $new_value,
						       'string',
						       $env{'user.name'},
					               $env{'user.domain'});
	&Apache::lonxml::debug("hrrm $result");
	return $wanted;
    }

    # someone else got it
    return undef;
}

sub remove_registration {
    my ($r) = @_;
    if ($env{'form.entry'} ne 'remove all') {
	return &remove_registration_user($r);
    }
    my $slot_name = $env{'form.slotname'};
    my %slot=&Apache::lonnet::get_slot($slot_name);

    my ($cnum,$cdom)=&get_course();
    my %consumed=&Apache::lonnet::dump('slot_reservations',$cdom,$cnum,
				       "^$slot_name\0");
    if (&Apache::lonnet::error(%consumed)) {
	$r->print("<p><span class=\"LC_error\">".&mt('A network error has occured.').'</span></p>');
	return;
    }
    if (!%consumed) {
	$r->print("<p>".&mt('Slot <tt>[_1]</tt> has no reservations.',
			    $slot_name)."</p>");
	return;
    }

    my @names = map { $consumed{$_}{'name'} } (sort(keys(%consumed)));
    my $names = join(' ',@names);

    my $msg = &mt('Remove all of [_1] from slot [_2]?',$names,$slot_name);
    &remove_registration_confirmation($r,$msg,['entry','slotname']);
}

sub remove_registration_user {
    my ($r) = @_;
    
    my $slot_name = $env{'form.slotname'};

    my $name = &Apache::loncommon::plainname($env{'form.uname'},
					     $env{'form.udom'});

    my $title = &Apache::lonnet::gettitle($env{'form.symb'});

    my $msg = &mt('Remove [_1] from slot [_2] for [_3]',
		  $name,$slot_name,$title);
    
    &remove_registration_confirmation($r,$msg,['uname','udom','slotname',
					       'entry','symb']);
}

sub remove_registration_confirmation {
    my ($r,$msg,$inputs) =@_;

    my $hidden_input;
    foreach my $parm (@{$inputs}) {
	$hidden_input .=
	    '<input type="hidden" name="'.$parm.'" value="'
	    .&HTML::Entities::encode($env{'form.'.$parm},'"<>&\'').'" />'."\n";
    }
    my %lt = &Apache::lonlocal::texthash('yes' => 'Yes',
					 'no'  => 'No',);
    $r->print(<<"END_CONFIRM");
<p> $msg </p>
<form action="/adm/slotrequest" method="post">
    <input type="hidden" name="command" value="release" />
    <input type="hidden" name="button" value="yes" />
    $hidden_input
    <input type="submit" value="$lt{'yes'}" />
</form>
<form action="/adm/slotrequest" method="post">
    <input type="hidden" name="command" value="showslots" />
    <input type="submit" value="$lt{'no'}" />
</form>
END_CONFIRM

}

sub release_all_slot {
    my ($r,$mgr)=@_;
    
    my $slot_name = $env{'form.slotname'};

    my ($cnum,$cdom)=&get_course();

    my %consumed=&Apache::lonnet::dump('slot_reservations',$cdom,$cnum,
				       "^$slot_name\0");
    
    $r->print('<p>'.&mt('Releasing reservations').'</p>');

    foreach my $entry (sort { $consumed{$a}{'name'} cmp 
				  $consumed{$b}{'name'} } (keys(%consumed))) {
	my ($uname,$udom) = split(':',$consumed{$entry}{'name'});
	my ($result,$msg) =
	    &release_reservation($slot_name,$uname,$udom,
				 $consumed{$entry}{'symb'},$mgr);
	$r->print("<p>$msg</p>");
	$r->rflush();
    }
    $r->print('<p><a href="/adm/slotrequest?command=showslots">'.
	      &mt('Return to slot list').'</a></p>');
    &return_link($r);
}

sub release_slot {
    my ($r,$symb,$slot_name,$inhibit_return_link,$mgr)=@_;

    if ($slot_name eq '') { $slot_name=$env{'form.slotname'}; }

    my ($uname,$udom) = ($env{'user.name'}, $env{'user.domain'});
    if ($mgr eq 'F' 
	&& defined($env{'form.uname'}) && defined($env{'form.udom'})) {
	($uname,$udom) = ($env{'form.uname'}, $env{'form.udom'});
    }

    if ($mgr eq 'F' 
	&& defined($env{'form.symb'})) {
	$symb = &unescape($env{'form.symb'});
    }

    my ($result,$msg) =
	&release_reservation($slot_name,$uname,$udom,$symb,$mgr);
    $r->print("<p>$msg</p>");
    
    if ($mgr eq 'F') {
	$r->print('<p><a href="/adm/slotrequest?command=showslots">'.
		  &mt('Return to slot list').'</a></p>');
    }

    if (!$inhibit_return_link) { &return_link($r);  }
    return $result;
}

sub release_reservation {
    my ($slot_name,$uname,$udom,$symb,$mgr) = @_;
    my %slot=&Apache::lonnet::get_slot($slot_name);
    my $description=&get_description($slot_name,\%slot);

    if ($mgr ne 'F') {
	if ($slot{'starttime'} < time) {
	    return (0,&mt('Not allowed to release Reservation: [_1], as it has already ended.',$description));
	}
    }
    # get parameter string, check for existance, rebuild string with the slot
    my @slots = split(/:/,&Apache::lonnet::EXT("resource.0.availablestudent",
					       $symb,$udom,$uname));

    my @new_slots;
    foreach my $exist_slot (@slots) {
	if ($exist_slot eq $slot_name) { next; }
	push(@new_slots,$exist_slot);
    }
    my $new_param = join(':',@new_slots);

    my ($cnum,$cdom)=&get_course();

    # get slot reservations, check if user has one, if so remove reservation
    my %consumed=&Apache::lonnet::dump('slot_reservations',$cdom,$cnum,
				       "^$slot_name\0");
    foreach my $entry (keys(%consumed)) {
	if ( $consumed{$entry}->{'name'} eq ($uname.':'.$udom) ) {
	    &Apache::lonnet::del('slot_reservations',[$entry],
				 $cdom,$cnum);
	}
    }

    my $use_slots = &Apache::lonnet::EXT("resource.0.useslots");
    &Apache::lonxml::debug("use_slots is  $use_slots<br />");

    if (&Apache::lonnet::error($use_slots)) { 
	return (0,'error: Unable to determine current status');
    }

    my $parm_level = 1;
    if ($use_slots eq 'map' || $use_slots eq 'map_map') {
	$parm_level = 2;
    }
    # store new parameter string
    my $result=&Apache::lonparmset::storeparm_by_symb($symb,
						      '0_availablestudent',
						      $parm_level, $new_param,
						      'string', $uname, $udom);

    my $msg;
    if ($mgr eq 'F') {
	$msg = &mt('Released Reservation for user: [_1]',"$uname:$udom");
    } else {
	$msg = &mt('Released Reservation: [_1]',$description);
    }
    return (1,$msg);
}

sub delete_slot {
    my ($r)=@_;

    my $slot_name = $env{'form.slotname'};
    my %slot=&Apache::lonnet::get_slot($slot_name);

    my ($cnum,$cdom)=&get_course();
    my %consumed=&Apache::lonnet::dump('slot_reservations',$cdom,$cnum,
				       "^$slot_name\0");
    my ($tmp) = %consumed;
    if ($tmp =~ /error: 2/) { undef(%consumed); }

    if (%slot && !%consumed) {
	$slot{'type'} = 'deleted';
	my $ret = &Apache::lonnet::cput('slots', {$slot_name => \%slot},
					$cdom, $cnum);
	if ($ret eq 'ok') {
	    $r->print("<p>Slot <tt>$slot_name</tt> marked as deleted.</p>");
	} else {
	    $r->print("<p><span class=\"LC_error\"> An error ($ret) occurse when attempting to delete Slot <tt>$slot_name</tt>.</span></p>");
	}
    } else {
	if (%consumed) {
	    $r->print("<p>Slot <tt>$slot_name</tt> has active reservations.</p>");
	} else {
	    $r->print("<p>Slot <tt>$slot_name</tt> does not exist.</p>");
	}
    }
    $r->print('<p><a href="/adm/slotrequest?command=showslots">'.
	      &mt('Return to slot list').'</a></p>');
    &return_link($r);
}

sub return_link {
    my ($r) = @_;
    $r->print('<p><a href="/adm/flip?postdata=return:">'.
	      &mt('Return to last resource').'</a></p>');
}

sub get_slot {
    my ($r,$symb,$conflictable_slot,$inhibit_return_link)=@_;

    my %slot=&Apache::lonnet::get_slot($env{'form.slotname'});
    my $slot_name=&check_for_conflict($symb,$env{'form.slotname'},\%slot);

    if ($slot_name =~ /^error: (.*)/) {
	$r->print("<p><span class=\"LC_error\">An error occured while attempting to make a reservation. ($1)</span></p>");
	&return_link($r);
	return 0;
    }
    if ($slot_name && $slot_name ne $conflictable_slot) {
	my %slot=&Apache::lonnet::get_slot($slot_name);
	my $description1=&get_description($slot_name,\%slot);
	%slot=&Apache::lonnet::get_slot($env{'form.slotname'});
	my $description2=&get_description($env{'form.slotname'},\%slot);
	$r->print("<p>Already have a reservation: $description1</p>");
	if ($slot_name ne $env{'form.slotname'}) {
	    $r->print(<<STUFF);
<form method="post" action="/adm/slotrequest">
   <input type="hidden" name="symb" value="$env{'form.symb'}" />
   <input type="hidden" name="slotname" value="$env{'form.slotname'}" />
   <input type="hidden" name="releaseslot" value="$slot_name" />
   <input type="hidden" name="command" value="change" />
STUFF
            $r->print("<p>You can either ");
	    $r->print(<<STUFF);
   <input type="submit" name="change" value="Change" />
STUFF
	    $r->print(' your reservation from <b>'.$description1.'</b> to <b>'.
		      $description2.
		      '</b> <br />or </p>');
	    &return_link($r);
	    $r->print(<<STUFF);
</form>
STUFF
        } else {
	    &return_link($r);
	}
	return 0;
    }

    my $reserved=&make_reservation($env{'form.slotname'},
				   \%slot,$symb);
    my $description=&get_description($env{'form.slotname'},\%slot);
    if (defined($reserved)) {
	my $retvalue = 0;
	if ($slot_name =~ /^error: (.*)/) {
	    $r->print("<p><span class=\"LC_error\">An error occured while attempting to make a reservation. ($1)</span></p>");
	} elsif ($reserved > -1) {
	    $r->print("<p>Success: $description</p>");
	    $retvalue = 1;
	} elsif ($reserved < 0) {
	    $r->print("<p>Already reserved: $description</p>");
	}
	if (!$inhibit_return_link) { &return_link($r); }
	return 1;
    }

    my %lt=('request'=>"Availibility list",
	    'try'    =>'Try again');
    %lt=&Apache::lonlocal::texthash(%lt);

    my $extra_input;
    if ($conflictable_slot) {
	$extra_input='<input type="hidden" name="releaseslot" value="'.$env{'form.slotname'}.'" />';
    }

    $r->print(<<STUFF);
<p> <span class="LC_warning">Failed</span> to reserve a spot for $description. </p>
<p>
<form method="post" action="/adm/slotrequest">
   <input type="submit" name="Try Again" value="$lt{'try'}" />
   <input type="hidden" name="symb" value="$env{'form.symb'}" />
   <input type="hidden" name="slotname" value="$env{'form.slotname'}" />
   <input type="hidden" name="command" value="$env{'form.command'}" />
   $extra_input
</form>
?
</p>
<p>
or
<form method="post" action="/adm/slotrequest">
    <input type="hidden" name="symb" value="$env{'form.symb'}" />
    <input type="submit" name="requestattempt" value="$lt{'request'}" />
</form>
</p>
or
STUFF

    if (!$inhibit_return_link) { &return_link($r); }
    return 0;
}

sub allowed_slot {
    my ($slot_name,$slot,$symb,$slots,$consumed_uniqueperiods)=@_;

    #already started
    if ($slot->{'starttime'} < time) {
	return 0;
    }
    &Apache::lonxml::debug("$slot_name starttime good");

    #already ended
    if ($slot->{'endtime'} < time) {
	return 0;
    }
    &Apache::lonxml::debug("$slot_name endtime good");

    # not allowed to pick this one
    if (defined($slot->{'type'})
	&& $slot->{'type'} ne 'schedulable_student') {
	return 0;
    }
    &Apache::lonxml::debug("$slot_name type good");

    # reserve time not yet started
    if ($slot->{'startreserve'} > time) {
	return 0;
    }
    &Apache::lonxml::debug("$slot_name reserve good");

    my $userallowed=0;
    # its for a different set of users
    if (defined($slot->{'allowedsections'})) {
	if (!defined($env{'request.role.sec'})
	    && grep(/^No section assigned$/,
		    split(',',$slot->{'allowedsections'}))) {
	    $userallowed=1;
	}
	if (defined($env{'request.role.sec'})
	    && grep(/^\Q$env{'request.role.sec'}\E$/,
		    split(',',$slot->{'allowedsections'}))) {
	    $userallowed=1;
	}
	if (defined($env{'request.course.groups'})) {
	    my @groups = split(/:/,$env{'request.course.groups'});
	    my @allowed_sec = split(',',$slot->{'allowedsections'});
	    foreach my $group (@groups) {
		if (grep {$_ eq $group} (@allowed_sec)) {
		    $userallowed=1;
		    last;
		}
	    }
	}
    }
    &Apache::lonxml::debug("$slot_name sections is $userallowed");

    # its for a different set of users
    if (defined($slot->{'allowedusers'})
	&& grep(/^\Q$env{'user.name'}:$env{'user.domain'}\E$/,
		split(',',$slot->{'allowedusers'}))) {
	$userallowed=1;
    }

    if (!defined($slot->{'allowedusers'})
	&& !defined($slot->{'allowedsections'})) {
	$userallowed=1;
    }

    &Apache::lonxml::debug("$slot_name user is $userallowed");
    return 0 if (!$userallowed);

    # not allowed for this resource
    if (defined($slot->{'symb'})
	&& $slot->{'symb'} ne $symb) {
	return 0;
    }

    my $conflict = &check_for_conflict($symb,$slot_name,$slot,$slots,
				       $consumed_uniqueperiods);
    if ($conflict) {
	if ($slots->{$conflict}{'starttime'} < time) {
	    return 0;
	}
    }
    &Apache::lonxml::debug("$slot_name symb good");
    return 1;
}

sub get_description {
    my ($slot_name,$slot)=@_;
    my $description=$slot->{'description'};
    if (!defined($description)) {
	$description=&mt('[_1] From [_2] to [_3]',$slot_name,
			 &Apache::lonlocal::locallocaltime($slot->{'starttime'}),
			 &Apache::lonlocal::locallocaltime($slot->{'endtime'}));
    }
    return $description;
}

sub show_choices {
    my ($r,$symb)=@_;

    my ($cnum,$cdom)=&get_course();
    my %slots=&Apache::lonnet::dump('slots',$cdom,$cnum);
    my $consumed_uniqueperiods = &get_consumed_uniqueperiods(\%slots);
    my $available;
    $r->print('<table border="1">');
    &Apache::lonxml::debug("Checking Slots");
    my @got_slots=&check_for_reservation($symb,'allslots');
    foreach my $slot (sort 
		      { return $slots{$a}->{'starttime'} <=> $slots{$b}->{'starttime'} }
		      (keys(%slots)))  {

	&Apache::lonxml::debug("Checking Slot $slot");
	next if (!&allowed_slot($slot,$slots{$slot},undef,\%slots,
				$consumed_uniqueperiods));

	$available++;

	my $description=&get_description($slot,$slots{$slot});

	my $form=&mt('Unavailable');
	if ((grep(/^\Q$slot\E$/,@got_slots)) ||
	    &space_available($slot,$slots{$slot},$symb)) {
	    my $text=&mt('Select');
	    my $command='get';
	    if (grep(/^\Q$slot\E$/,@got_slots)) {
		$text=&mt('Drop Reservation');
		$command='release';
	    } else {
		my $conflict = &check_for_conflict($symb,$slot,$slots{$slot},
						   \%slots,
						   $consumed_uniqueperiods);
		if ($conflict) {
		    $text=&mt('Change Reservation');
		    $command='get';
		}
	    }
	    my $escsymb=&escape($symb);
	    $form=<<STUFF;
   <form method="post" action="/adm/slotrequest">
     <input type="submit" name="Select" value="$text" />
     <input type="hidden" name="symb" value="$escsymb" />
     <input type="hidden" name="slotname" value="$slot" />
     <input type="hidden" name="command" value="$command" />
   </form>
STUFF
	}
	$r->print(<<STUFF);
<tr>
 <td>$form</td>
 <td>$description</td>
</tr>
STUFF
    }

    if (!$available) {
	$r->print('<tr><td>No available times. <a href="/adm/flip?postdata=return:">'.
		  &mt('Return to last resource').'</a></td></tr>');
    }
    $r->print('</table>');
}

sub to_show {
    my ($slotname,$slot,$when,$deleted,$name) = @_;
    my $time=time;
    my $week=60*60*24*7;

    if ($deleted eq 'hide' && $slot->{'type'} eq 'deleted') {
	return 0;
    }

    if ($name && $name->{'value'} =~ /\w/) {
	if ($name->{'type'} eq 'substring') {
	    if ($slotname !~ /\Q$name->{'value'}\E/) {
		return 0;
	    }
	}
	if ($name->{'type'} eq 'exact') {
	    if ($slotname eq $name->{'value'}) {
		return 0;
	    }
	}
    }

    if ($when eq 'any') {
	return 1;
    } elsif ($when eq 'now') {
	if ($time > $slot->{'starttime'} &&
	    $time < $slot->{'endtime'}) {
	    return 1;
	}
	return 0;
    } elsif ($when eq 'nextweek') {
	if ( ($time        < $slot->{'starttime'} &&
	      ($time+$week) > $slot->{'starttime'})
	     ||
	     ($time        < $slot->{'endtime'} &&
	      ($time+$week) > $slot->{'endtime'}) ) {
	    return 1;
	}
	return 0;
    } elsif ($when eq 'lastweek') {
	if ( ($time        > $slot->{'starttime'} &&
	      ($time-$week) < $slot->{'starttime'})
	     ||
	     ($time        > $slot->{'endtime'} &&
	      ($time-$week) < $slot->{'endtime'}) ) {
	    return 1;
	}
	return 0;
    } elsif ($when eq 'willopen') {
	if ($time < $slot->{'starttime'}) {
	    return 1;
	}
	return 0;
    } elsif ($when eq 'wereopen') {
	if ($time > $slot->{'endtime'}) {
	    return 1;
	}
	return 0;
    }
    
    return 1;
}

sub remove_link {
    my ($slotname,$entry,$uname,$udom,$symb) = @_;

    my $remove = &mt('Remove');

    if ($entry eq 'remove all') {
	$remove = &mt('Remove All');
	undef($uname);
	undef($udom);
    }

    $slotname  = &escape($slotname);
    $entry     = &escape($entry);
    $uname     = &escape($uname);
    $udom      = &escape($udom);
    $symb      = &escape($symb);

    return <<"END_LINK";
 <a href="/adm/slotrequest?command=remove_registration&amp;slotname=$slotname&amp;entry=$entry&amp;uname=$uname&amp;udom=$udom&amp;symb=$symb"
   >($remove)</a>
END_LINK

}

sub show_table {
    my ($r,$mgr)=@_;

    my ($cnum,$cdom)=&get_course();
    my %slots=&Apache::lonnet::dump('slots',$cdom,$cnum);
    if ( (keys(%slots))[0] =~ /^error: 2 /) {
	undef(%slots);
    } 
    my $available;
    if ($mgr eq 'F') {
    # FIXME: This line should be deleted once Slots uses breadcrumbs
    $r->print(&Apache::loncommon::help_open_topic('Slot About', 'Help on slots'));

	$r->print('<div>');
	$r->print('<form method="post" action="/adm/slotrequest">
<input type="hidden" name="command" value="uploadstart" />
<input type="submit" name="start" value="'.&mt('Upload Slot List').'" />
</form>');
	$r->print(&Apache::loncommon::help_open_topic('Slot CommaDelimited'));
	$r->print('<form method="post" action="/adm/helper/newslot.helper">
<input type="submit" name="newslot" value="'.&mt('Create a New Slot').'" />
</form>');
	$r->print(&Apache::loncommon::help_open_topic('Slot AddInterface'));
	$r->print('</div>');
    }
    
    my %Saveable_Parameters = ('show'              => 'array',
			       'when'              => 'scalar',
			       'order'             => 'scalar',
			       'deleted'           => 'scalar',
			       'name_filter_type'  => 'scalar',
			       'name_filter_value' => 'scalar',
			       );
    &Apache::loncommon::store_course_settings('slotrequest',
					      \%Saveable_Parameters);
    &Apache::loncommon::restore_course_settings('slotrequest',
						\%Saveable_Parameters);
    &Apache::grades::init_perm();
    my ($classlist,$section,$fullname)=&Apache::grades::getclasslist('all');
    &Apache::grades::reset_perm();

    # what to display filtering
    my %show_fields=&Apache::lonlocal::texthash(
	     'name'            => 'Slot Name',
	     'description'     => 'Description',
	     'type'            => 'Type',
	     'starttime'       => 'Start time',
	     'endtime'         => 'End Time',
             'startreserve'    => 'Time students can start reserving',
	     'secret'          => 'Secret Word',
	     'space'           => '# of students/max',
	     'ip'              => 'IP or DNS restrictions',
	     'symb'            => 'Resource slot is restricted to.',
	     'allowedsections' => 'Sections slot is restricted to.',
	     'allowedusers'    => 'Users slot is restricted to.',
	     'uniqueperiod'    => 'Period of time slot is unique',
	     'scheduled'       => 'Scheduled Students',
	     'proctor'         => 'List of proctors');
    my @show_order=('name','description','type','starttime','endtime',
		    'startreserve','secret','space','ip','symb',
		    'allowedsections','allowedusers','uniqueperiod',
		    'scheduled','proctor');
    my @show = 
	(exists($env{'form.show'})) ? &Apache::loncommon::get_env_multiple('form.show')
	                            : keys(%show_fields);
    my %show =  map { $_ => 1 } (@show);

    #when filtering setup
    my %when_fields=&Apache::lonlocal::texthash(
	     'now'      => 'Open now',
	     'nextweek' => 'Open within the next week',
	     'lastweek' => 'Were open last week',
	     'willopen' => 'Will open later',
	     'wereopen' => 'Were open',
	     'any'      => 'Anytime',
						);
    my @when_order=('any','now','nextweek','lastweek','willopen','wereopen');
    $when_fields{'select_form_order'} = \@when_order;
    my $when = 	(exists($env{'form.when'})) ? $env{'form.when'}
                                            : 'now';

    #display of students setup
    my %stu_display_fields=
	&Apache::lonlocal::texthash('username' => 'User name',
				    'fullname' => 'Full name',
				    );
    my @stu_display_order=('fullname','username');
    my @stu_display = 
	(exists($env{'form.studisplay'})) ? &Apache::loncommon::get_env_multiple('form.studisplay')
	                                  : keys(%stu_display_fields);
    my %stu_display =  map { $_ => 1 } (@stu_display);

    #name filtering setup
    my %name_filter_type_fields=
	&Apache::lonlocal::texthash('substring' => 'Substring',
				    'exact'     => 'Exact',
				    #'reg'       => 'Regular Expression',
				    );
    my @name_filter_type_order=('substring','exact');

    $name_filter_type_fields{'select_form_order'} = \@name_filter_type_order;
    my $name_filter_type = 
	(exists($env{'form.name_filter_type'})) ? $env{'form.name_filter_type'}
                                                : 'substring';
    my $name_filter = {'type'  => $name_filter_type,
		       'value' => $env{'form.name_filter_value'},};

    
    #deleted slot filtering
    #default to hide if no value
    $env{'form.deleted'} ||= 'hide';
    my $hide_radio = 
	&Apache::lonhtmlcommon::radio('deleted',$env{'form.deleted'},'hide');
    my $show_radio = 
	&Apache::lonhtmlcommon::radio('deleted',$env{'form.deleted'},'show');
	
    $r->print('<form method="post" action="/adm/slotrequest">
<input type="hidden" name="command" value="showslots" />');
    $r->print('<div>');
    $r->print('<table class="inline">
      <tr><th>'.&mt('Show').'</th>
          <th>'.&mt('Student Display').'</th>
          <th>'.&mt('Open').'</th>
          <th>'.&mt('Slot Name Filter').'</th>
          <th>'.&mt('Options').'</th>
      </tr>
      <tr><td>'.&Apache::loncommon::multiple_select_form('show',\@show,6,\%show_fields,\@show_order).
	      '</td>
           <td>
         '.&Apache::loncommon::multiple_select_form('studisplay',\@stu_display,
						    6,\%stu_display_fields,
						    \@stu_display_order).'
           </td>
           <td>'.&Apache::loncommon::select_form($when,'when',%when_fields).
          '</td>
           <td>'.&Apache::loncommon::select_form($name_filter_type,
						 'name_filter_type',
						 %name_filter_type_fields).
	      '<br />'.
	      &Apache::lonhtmlcommon::textbox('name_filter_value',
					      $env{'form.name_filter_value'},
					      15).
          '</td>
           <td>
            <table>
              <tr>
                <td rowspan="2">Deleted slots:</td>
                <td><label>'.$show_radio.'Show</label></td>
              </tr>
              <tr>
                <td><label>'.$hide_radio.'Hide</label></td>
              </tr>
            </table>
	  </td>
       </tr>
    </table>');
    $r->print('</div>');
    $r->print('<p><input type="submit" name="start" value="'.&mt('Update Display').'" /></p>');
    my $linkstart='<a href="/adm/slotrequest?command=showslots&amp;order=';
    $r->print(&Apache::loncommon::start_data_table().
	      &Apache::loncommon::start_data_table_header_row().'
	       <th></th>');
    foreach my $which (@show_order) {
	if ($which ne 'proctor' && exists($show{$which})) {
	    $r->print('<th>'.$linkstart.$which.'">'.$show_fields{$which}.'</a></th>');
	}
    }
    $r->print(&Apache::loncommon::end_data_table_header_row());

    my %name_cache;
    my $slotsort = sub {
	if ($env{'form.order'}=~/^(type|description|endtime|startreserve|ip|symb|allowedsections|allowedusers)$/) {
	    if (lc($slots{$a}->{$env{'form.order'}})
		ne lc($slots{$b}->{$env{'form.order'}})) {
		return (lc($slots{$a}->{$env{'form.order'}}) 
			cmp lc($slots{$b}->{$env{'form.order'}}));
	    }
	} elsif ($env{'form.order'} eq 'space') {
	    if ($slots{$a}{'maxspace'} ne $slots{$b}{'maxspace'}) {
		return ($slots{$a}{'maxspace'} cmp $slots{$b}{'maxspace'});
	    }
	} elsif ($env{'form.order'} eq 'name') {
	    if (lc($a) cmp lc($b)) {
		return lc($a) cmp lc($b);
	    }
	} elsif ($env{'form.order'} eq 'uniqueperiod') {
	    
	    if ($slots{$a}->{'uniqueperiod'}[0] 
		ne $slots{$b}->{'uniqueperiod'}[0]) {
		return ($slots{$a}->{'uniqueperiod'}[0]
			cmp $slots{$b}->{'uniqueperiod'}[0]);
	    }
	    if ($slots{$a}->{'uniqueperiod'}[1] 
		ne $slots{$b}->{'uniqueperiod'}[1]) {
		return ($slots{$a}->{'uniqueperiod'}[1]
			cmp $slots{$b}->{'uniqueperiod'}[1]);
	    }
	}
	return $slots{$a}->{'starttime'} <=> $slots{$b}->{'starttime'};
    };

    my %consumed;
    if (exists($show{'scheduled'}) || exists($show{'space'}) ) {
	%consumed=&Apache::lonnet::dump('slot_reservations',$cdom,$cnum);
	my ($tmp)=%consumed;
	if ($tmp =~ /^error: /) { undef(%consumed); }
    }

    foreach my $slot (sort $slotsort (keys(%slots)))  {
	if (!&to_show($slot,$slots{$slot},$when,
		      $env{'form.deleted'},$name_filter)) { next; }
	if (defined($slots{$slot}->{'type'})
	    && $slots{$slot}->{'type'} ne 'schedulable_student') {
	    #next;
	}
	my $description=&get_description($slot,$slots{$slot});
	my ($id_count,$ids);
	    
	if (exists($show{'scheduled'}) || exists($show{'space'}) ) {
	    my $re_str = "$slot\0";
	    my @this_slot = grep(/^\Q$re_str\E/,keys(%consumed));
	    $id_count = scalar(@this_slot);
	    if (exists($show{'scheduled'})) {
		foreach my $entry (sort { $consumed{$a}{name} cmp 
					      $consumed{$b}{name} }
				   (@this_slot)) {
		    my (undef,$id)=split("\0",$entry);
		    my ($uname,$udom) = split(':',$consumed{$entry}{'name'});
		    $ids.= '<nobr>';
		    foreach my $item (@stu_display_order) {
			if ($stu_display{$item}) {
			    if ($item eq 'fullname') {
				$ids.=$fullname->{"$uname:$udom"}.' ';
			    } elsif ($item eq 'username') {
				$ids.="<tt>$uname:$udom</tt> ";
			    }
			}
		    }
		    $ids.=&remove_link($slot,$entry,$uname,$udom,
				       $consumed{$entry}{'symb'}).'</nobr><br />';
		}
	    }
	}

	my $start=($slots{$slot}->{'starttime'}?
		   &Apache::lonlocal::locallocaltime($slots{$slot}->{'starttime'}):'');
	my $end=($slots{$slot}->{'endtime'}?
		 &Apache::lonlocal::locallocaltime($slots{$slot}->{'endtime'}):'');
	my $start_reserve=($slots{$slot}->{'startreserve'}?
			   &Apache::lonlocal::locallocaltime($slots{$slot}->{'startreserve'}):'');
	
	my $unique;
	if (ref($slots{$slot}{'uniqueperiod'})) {
	    $unique=localtime($slots{$slot}{'uniqueperiod'}[0]).', '.
		localtime($slots{$slot}{'uniqueperiod'}[1]);
	}

	my $title;
	if (exists($slots{$slot}{'symb'})) {
	    my (undef,undef,$res)=
		&Apache::lonnet::decode_symb($slots{$slot}{'symb'});
	    $res =   &Apache::lonnet::clutter($res);
	    $title = &Apache::lonnet::gettitle($slots{$slot}{'symb'});
	    $title='<a href="'.$res.'?symb='.$slots{$slot}{'symb'}.'">'.$title.'</a>';
	}

	my $allowedsections;
	if (exists($show{'allowedsections'})) {
	    $allowedsections = 
		join(', ',sort(split(/\s*,\s*/,
				     $slots{$slot}->{'allowedsections'})));
	}

	my @allowedusers;
	if (exists($show{'allowedusers'})) {
	    @allowedusers= map {
		my ($uname,$udom)=split(/:/,$_);
		my $fullname=$name_cache{$_};
		if (!defined($fullname)) {
		    $fullname = &Apache::loncommon::plainname($uname,$udom);
		    $fullname =~s/\s/&nbsp;/g;
		    $name_cache{$_} = $fullname;
		}
		&Apache::loncommon::aboutmewrapper($fullname,$uname,$udom);
	    } (sort(split(/\s*,\s*/,$slots{$slot}->{'allowedusers'})));
	}
	my $allowedusers=join(', ',@allowedusers);
	
	my @proctors;
	my $rowspan=1;
	my $colspan=1;
	if (exists($show{'proctor'})) {
	    $rowspan=2;
	    @proctors= map {
		my ($uname,$udom)=split(/:/,$_);
		my $fullname=$name_cache{$_};
		if (!defined($fullname)) {
		    $fullname = &Apache::loncommon::plainname($uname,$udom);
		    $fullname =~s/\s/&nbsp;/g;
		    $name_cache{$_} = $fullname;
		}
		&Apache::loncommon::aboutmewrapper($fullname,$uname,$udom);
	    } (sort(split(/\s*,\s*/,$slots{$slot}->{'proctor'})));
	}
	my $proctors=join(', ',@proctors);

	my $edit=(<<"EDITLINK");
<a href="/adm/helper/newslot.helper?name=$slot">Edit</a>
EDITLINK

	my $delete=(<<"DELETELINK");
<a href="/adm/slotrequest?command=delete&amp;slotname=$slot">Delete</a>
DELETELINK

        my $remove_all=&remove_link($slot,'remove all').'<br />';

        if ($ids ne '') { undef($delete); }
	if ($slots{$slot}{'type'} ne 'schedulable_student' 
	    || $ids eq '') { 
	    undef($remove_all);
	}

	my $row_start=&Apache::loncommon::start_data_table_row();
	my $row_end=&Apache::loncommon::end_data_table_row();
        $r->print($row_start.
		  "\n<td rowspan=\"$rowspan\">$edit $delete</td>\n");
	if (exists($show{'name'})) {
	    $colspan++;$r->print("<td>$slot</td>");
	}
	if (exists($show{'description'})) {
	    $colspan++;$r->print("<td>$description</td>\n");
	}
	if (exists($show{'type'})) {
	    $colspan++;$r->print("<td>$slots{$slot}->{'type'}</td>\n");
	}
	if (exists($show{'starttime'})) {
	    $colspan++;$r->print("<td>$start</td>\n");
	}
	if (exists($show{'endtime'})) {
	    $colspan++;$r->print("<td>$end</td>\n");
	}
	if (exists($show{'startreserve'})) {
	    $colspan++;$r->print("<td>$start_reserve</td>\n");
	}
	if (exists($show{'secret'})) {
	    $colspan++;$r->print("<td>$slots{$slot}{'secret'}</td>\n");
	}
	if (exists($show{'space'})) {
	    my $display = $id_count;
	    if ($slots{$slot}{'maxspace'}>0) {
		$display.='/'.$slots{$slot}{'maxspace'};
		if ($slots{$slot}{'maxspace'} <= $id_count) {
		    $display = '<strong>'.$display.' (full) </strong>';
		}
	    }
	    $colspan++;$r->print("<td>$display</td>\n");
	}
	if (exists($show{'ip'})) {
	    $colspan++;$r->print("<td>$slots{$slot}{'ip'}</td>\n");
	}
	if (exists($show{'symb'})) {
	    $colspan++;$r->print("<td>$title</td>\n");
	}
	if (exists($show{'allowedsections'})) {
	    $colspan++;$r->print("<td>$allowedsections</td>\n");
	}
	if (exists($show{'allowedusers'})) {
	    $colspan++;$r->print("<td>$allowedusers</td>\n");
	}
	if (exists($show{'uniqueperiod'})) {
	    $colspan++;$r->print("<td>$unique</td>\n");
	}
	if (exists($show{'scheduled'})) {
	    $colspan++;$r->print("<td>$remove_all $ids</td>\n");
	}
	$r->print("$row_end\n");
	if (exists($show{'proctor'})) {
	    $r->print(<<STUFF);
$row_start
 <td colspan="$colspan">$proctors</td>
$row_end
STUFF
        }
    }
    $r->print('</table></form>');
}

sub upload_start {
    my ($r)=@_;    
    $r->print(&Apache::grades::checkforfile_js());
    my $result.='<table width=100% border=0><tr bgcolor="#e6ffff"><td>'."\n";
    $result.='&nbsp;<b>'.
	&mt('Specify a file containing the slot definitions.').
	'</b></td></tr>'."\n";
    $result.='<tr bgcolor=#ffffe6><td>'."\n";
    my $upfile_select=&Apache::loncommon::upfile_select_html();
    my $ignore=&mt('Ignore First Line');
    $result.=<<ENDUPFORM;
<form method="post" enctype="multipart/form-data" action="/adm/slotrequest" name="slotupload">
<input type="hidden" name="command" value="csvuploadmap" />
$upfile_select
<br /><input type="button" onClick="javascript:checkUpload(this.form);" value="Upload Data" />
<label><input type="checkbox" name="noFirstLine" />$ignore</label>
</form>
ENDUPFORM
    $result.='</td></tr></table>'."\n";
    $result.='</td></tr></table>'."\n";
    $r->print($result);
}

sub csvuploadmap_header {
    my ($r,$datatoken,$distotal)= @_;
    my $javascript;
    if ($env{'form.upfile_associate'} eq 'reverse') {
	$javascript=&csvupload_javascript_reverse_associate();
    } else {
	$javascript=&csvupload_javascript_forward_associate();
    }

    my $checked=(($env{'form.noFirstLine'})?' checked="checked"':'');
    my $ignore=&mt('Ignore First Line');
	my $help_field = &Apache::loncommon::help_open_topic('Slot SelectingField');

    $r->print(<<ENDPICK);
<form method="post" enctype="multipart/form-data" action="/adm/slotrequest" name="slotupload">
<h3>Identify fields $help_field</h3>	
Total number of records found in file: $distotal <hr />
Enter as many fields as you can. The system will inform you and bring you back
to this page if the data selected is insufficient to create the slots.<hr />
<input type="button" value="Reverse Association" onClick="javascript:this.form.associate.value='Reverse Association';submit(this.form);" />
<label><input type="checkbox" name="noFirstLine" $checked />$ignore</label>
<input type="hidden" name="associate"  value="" />
<input type="hidden" name="datatoken"  value="$datatoken" />
<input type="hidden" name="fileupload" value="$env{'form.fileupload'}" />
<input type="hidden" name="upfiletype" value="$env{'form.upfiletype'}" />
<input type="hidden" name="upfile_associate" 
                                       value="$env{'form.upfile_associate'}" />
<input type="hidden" name="command"    value="csvuploadassign" />
<hr />
<script type="text/javascript" language="Javascript">
$javascript
</script>
ENDPICK
    return '';

}

sub csvuploadmap_footer {
    my ($request,$i,$keyfields) =@_;
    $request->print(<<ENDPICK);
</table>
<input type="hidden" name="nfields" value="$i" />
<input type="hidden" name="keyfields" value="$keyfields" />
<input type="button" onClick="javascript:verify(this.form)" value="Create Slots" /><br />
</form>
ENDPICK
}

sub csvupload_javascript_reverse_associate {
    my $error1=&mt('You need to specify the name, starttime, endtime and a type');
    return(<<ENDPICK);
  function verify(vf) {
    var foundstart=0;
    var foundend=0;
    var foundname=0;
    var foundtype=0;
    for (i=0;i<=vf.nfields.value;i++) {
      tw=eval('vf.f'+i+'.selectedIndex');
      if (i==0 && tw!=0) { foundname=1; }
      if (i==1 && tw!=0) { foundtype=1; }
      if (i==2 && tw!=0) { foundstat=1; }
      if (i==3 && tw!=0) { foundend=1; }
    }
    if (foundstart==0 && foundend==0 && foundtype==0 && foundname==0) {
	alert('$error1');
	return;
    }
    vf.submit();
  }
  function flip(vf,tf) {
  }
ENDPICK
}

sub csvupload_javascript_forward_associate {
    my $error1=&mt('You need to specify the name, starttime, endtime and a type');
  return(<<ENDPICK);
  function verify(vf) {
    var foundstart=0;
    var foundend=0;
    var foundname=0;
    var foundtype=0;
    for (i=0;i<=vf.nfields.value;i++) {
      tw=eval('vf.f'+i+'.selectedIndex');
      if (tw==1) { foundname=1; }
      if (tw==2) { foundtype=1; }
      if (tw==3) { foundstat=1; }
      if (tw==4) { foundend=1; }
    }
    if (foundstart==0 && foundend==0 && foundtype==0 && foundname==0) {
	alert('$error1');
	return;
    }
    vf.submit();
  }
  function flip(vf,tf) {
  }
ENDPICK
}

sub csv_upload_map {
    my ($r)= @_;

    my $datatoken;
    if (!$env{'form.datatoken'}) {
	$datatoken=&Apache::loncommon::upfile_store($r);
    } else {
	$datatoken=$env{'form.datatoken'};
	&Apache::loncommon::load_tmp_file($r);
    }
    my @records=&Apache::loncommon::upfile_record_sep();
    if ($env{'form.noFirstLine'}) { shift(@records); }
    &csvuploadmap_header($r,$datatoken,$#records+1);
    my ($i,$keyfields);
    if (@records) {
	my @fields=&csvupload_fields();

	if ($env{'form.upfile_associate'} eq 'reverse') {	
	    &Apache::loncommon::csv_print_samples($r,\@records);
	    $i=&Apache::loncommon::csv_print_select_table($r,\@records,
							  \@fields);
	    foreach (@fields) { $keyfields.=$_->[0].','; }
	    chop($keyfields);
	} else {
	    unshift(@fields,['none','']);
	    $i=&Apache::loncommon::csv_samples_select_table($r,\@records,
							    \@fields);
	    my %sone=&Apache::loncommon::record_sep($records[0]);
	    $keyfields=join(',',sort(keys(%sone)));
	}
    }
    &csvuploadmap_footer($r,$i,$keyfields);

    return '';
}

sub csvupload_fields {
    return (['name','Slot name'],
	    ['type','Type of slot'],
	    ['starttime','Start Time of slot'],
	    ['endtime','End Time of slot'],
	    ['startreserve','Reservation Start Time'],
	    ['ip','IP or DNS restriction'],
	    ['proctor','List of proctor ids'],
	    ['description','Slot Description'],
	    ['maxspace','Maximum number of reservations'],
	    ['symb','Resource Restriction'],
	    ['uniqueperiod','Date range of slot exclusion'],
	    ['secret','Secret word proctor uses to validate'],
	    ['allowedsections','Sections slot is restricted to'],
	    ['allowedusers','Users slot is restricted to'],
	    );
}

sub csv_upload_assign {
    my ($r,$mgr)= @_;
    &Apache::loncommon::load_tmp_file($r);
    my @slotdata = &Apache::loncommon::upfile_record_sep();
    if ($env{'form.noFirstLine'}) { shift(@slotdata); }
    my %fields=&Apache::grades::get_fields();
    $r->print('<h3>Creating Slots</h3>');
    my $cname=$env{'course.'.$env{'request.course.id'}.'.num'};
    my $cdom=$env{'course.'.$env{'request.course.id'}.'.domain'};
    my $countdone=0;
    my @errors;
    foreach my $slot (@slotdata) {
	my %slot;
	my %entries=&Apache::loncommon::record_sep($slot);
	my $domain;
	my $name=$entries{$fields{'name'}};
	if ($name=~/^\s*$/) {
	    push(@errors,"Did not create slot with no name");
	    next;
	}
	if ($name=~/\s/) { 
	    push(@errors,"$name not created -- Name must not contain spaces");
	    next;
	}
	if ($name=~/\W/) { 
	    push(@errors,"$name not created -- Name must contain only letters, numbers and _");
	    next;
	}
	if ($entries{$fields{'type'}}) {
	    $slot{'type'}=$entries{$fields{'type'}};
	} else {
	    $slot{'type'}='preassigned';
	}
	if ($slot{'type'} ne 'preassigned' &&
	    $slot{'type'} ne 'schedulable_student') {
	    push(@errors,"$name not created -- invalid type ($slot{'type'}) must be either preassigned or schedulable_student");
	    next;
	}
	if ($entries{$fields{'starttime'}}) {
	    $slot{'starttime'}=&UnixDate($entries{$fields{'starttime'}},"%s");
	}
	if ($entries{$fields{'endtime'}}) {
	    $slot{'endtime'}=&UnixDate($entries{$fields{'endtime'}},"%s");
	}

	# start/endtime must be defined and greater than zero
	if (!$slot{'starttime'}) {
	    push(@errors,"$name not created -- Invalid start time");
	    next;
	}
	if (!$slot{'endtime'}) {
	    push(@errors,"$name not created -- Invalid end time");
	    next;
	}
	if ($slot{'starttime'} > $slot{'endtime'}) {
	    push(@errors,"$name not created -- Slot starts after it ends");
	    next;
	}

	if ($entries{$fields{'startreserve'}}) {
	    $slot{'startreserve'}=
		&UnixDate($entries{$fields{'startreserve'}},"%s");
	}
	if (defined($slot{'startreserve'})
	    && $slot{'startreserve'} > $slot{'starttime'}) {
	    push(@errors,"$name not created -- Slot's reservation start time is after the slot's start time.");
	    next;
	}

	foreach my $key ('ip','proctor','description','maxspace',
			 'secret','symb') {
	    if ($entries{$fields{$key}}) {
		$slot{$key}=$entries{$fields{$key}};
	    }
	}

	if ($entries{$fields{'uniqueperiod'}}) {
	    my ($start,$end)=split(',',$entries{$fields{'uniqueperiod'}});
	    my @times=(&UnixDate($start,"%s"),
		       &UnixDate($end,"%s"));
	    $slot{'uniqueperiod'}=\@times;
	}
	if (defined($slot{'uniqueperiod'})
	    && $slot{'uniqueperiod'}[0] > $slot{'uniqueperiod'}[1]) {
	    push(@errors,"$name not created -- Slot's unique period start time is later than the unique period's end time.");
	    next;
	}

	&Apache::lonnet::cput('slots',{$name=>\%slot},$cdom,$cname);
	$r->print('.');
	$r->rflush();
	$countdone++;
    }
    $r->print("<p>Created $countdone slots\n</p>");
    foreach my $error (@errors) {
	$r->print("<p><span class=\"LC_warning\">$error</span></p>\n");
    }
    &show_table($r,$mgr);
    return '';
}

sub handler {
    my $r=shift;

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

    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'});
    
    my $vgr=&Apache::lonnet::allowed('vgr',$env{'request.course.id'});
    my $mgr=&Apache::lonnet::allowed('mgr',$env{'request.course.id'});
    my $title='Requesting Another Worktime';
    if ($env{'form.command'} =~ /^(showslots|uploadstart|csvuploadmap|csvuploadassign)$/ && $vgr eq 'F') {
	$title = 'Managing Slots';
    }
    &start_page($r,$title);

    if ($env{'form.command'} eq 'showslots' && $vgr eq 'F') {
	&show_table($r,$mgr);
    } elsif ($env{'form.command'} eq 'remove_registration' && $mgr eq 'F') {
	&remove_registration($r);
    } elsif ($env{'form.command'} eq 'release' && $mgr eq 'F') {
	if ($env{'form.entry'} eq 'remove all') {
	    &release_all_slot($r,$mgr);
	} else {
	    &release_slot($r,undef,undef,undef,$mgr);
	}
    } elsif ($env{'form.command'} eq 'delete' && $mgr eq 'F') {
	&delete_slot($r);
    } elsif ($env{'form.command'} eq 'uploadstart' && $mgr eq 'F') {
	&upload_start($r);
    } elsif ($env{'form.command'} eq 'csvuploadmap' && $mgr eq 'F') {
	&csv_upload_map($r);
    } elsif ($env{'form.command'} eq 'csvuploadassign' && $mgr eq 'F') {
	if ($env{'form.associate'} ne 'Reverse Association') {
	    &csv_upload_assign($r,$mgr);
	} else {
	    if ( $env{'form.upfile_associate'} ne 'reverse' ) {
		$env{'form.upfile_associate'} = 'reverse';
	    } else {
		$env{'form.upfile_associate'} = 'forward';
	    }
	    &csv_upload_map($r);
	}
    } else {
	my $symb=&unescape($env{'form.symb'});
	if (!defined($symb)) {
	    &fail($r,'not_valid');
	    return OK;
	}
	my (undef,undef,$res)=&Apache::lonnet::decode_symb($symb);
	my $useslots = &Apache::lonnet::EXT("resource.0.useslots",$symb);
	if ($useslots ne 'resource' 
	    && $useslots ne 'map' 
	    && $useslots ne 'map_map') {
	    &fail($r,'not_available');
	    return OK;
	}
	$env{'request.symb'}=$symb;
	my $type = ($res =~ /\.task$/) ? 'Task'
	                               : 'problem';
	my ($status) = &Apache::lonhomework::check_slot_access('0',$type);
	if ($status eq 'CAN_ANSWER' ||
	    $status eq 'NEEDS_CHECKIN' ||
	    $status eq 'WAITING_FOR_GRADE') {
	    &fail($r,'not_allowed');
	    return OK;
	}
	if ($env{'form.requestattempt'}) {
	    &show_choices($r,$symb);
	} elsif ($env{'form.command'} eq 'release') {
	    &release_slot($r,$symb);
	} elsif ($env{'form.command'} eq 'get') {
	    &get_slot($r,$symb);
	} elsif ($env{'form.command'} eq 'change') {
	    if (&get_slot($r,$symb,$env{'form.releaseslot'},1)) {
		&release_slot($r,$symb,$env{'form.releaseslot'});
	    }
	} else {
	    $r->print("<p>Unknown command: ".$env{'form.command'}."</p>");
	}
    }
    &end_page($r);
    return OK;
}

1;
__END__