--- loncom/interface/slotrequest.pm	2005/09/13 08:12:03	1.18
+++ loncom/interface/slotrequest.pm	2007/04/10 23:30:41	1.76
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Handler for requesting to have slots added to a students record
 #
-# $Id: slotrequest.pm,v 1.18 2005/09/13 08:12:03 albertel Exp $
+# $Id: slotrequest.pm,v 1.76 2007/04/10 23:30:41 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -34,35 +34,35 @@ use Apache::Constants qw(:common :http :
 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>');
     }
     
-    $r->print('<p><a href="/adm/flip?postdata=return:">'.
-	      &mt('Return to last resource').'</a></p>');
+    &return_link($r);
     &end_page($r);
 }
 
 sub start_page {
-    my ($r)=@_;
-    my $html=&Apache::lonxml::xmlbegin();
-    $r->print($html.'<head><title>'.
-	      &mt('Request another Worktime').'</title></head>');
-    $r->print(&Apache::loncommon::bodytag('Requesting another Worktime'));
+    my ($r,$title)=@_;
+    $r->print(&Apache::loncommon::start_page($title));
 }
 
 sub end_page {
     my ($r)=@_;
-    $r->print(&Apache::loncommon::endbodytag().'</html>');
+    $r->print(&Apache::loncommon::end_page());
 }
 
 =pod
@@ -77,7 +77,7 @@ sub end_page {
 =cut
 
 sub get_course {
-    (undef,my $courseid)=&Apache::lonxml::whichuser();
+    (undef,my $courseid)=&Apache::lonnet::whichuser();
     my $cdom=$env{'course.'.$courseid.'.domain'};
     my $cnum=$env{'course.'.$courseid.'.num'};
     return ($cnum,$cdom);
@@ -90,7 +90,9 @@ sub get_reservation_ids {
 
     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;
@@ -112,7 +114,7 @@ sub space_available {
 }
 
 sub check_for_reservation {
-    my ($symb)=@_;
+    my ($symb,$mode)=@_;
     my $student = &Apache::lonnet::EXT("resource.0.availablestudent", $symb,
 				       $env{'user.domain'}, $env{'user.name'});
 
@@ -125,7 +127,20 @@ sub check_for_reservation {
     my ($cnum,$cdom)=&get_course();
     my %slots=&Apache::lonnet::get('slots', [@slots], $cdom, $cnum);
 
-    foreach my $slot_name (@slots) {
+    if (&Apache::lonnet::error($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." $slot_name ".
@@ -134,29 +149,82 @@ sub check_for_reservation {
 	if ($slots{$slot_name}->{'endtime'} > time &&
 	    $slots{$slot_name}->{'startreserve'} < time) {
 	    # between start of reservation times and end of slot
-	    return($slot_name, $slots{$slot_name});
+	    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)=@_;
-    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(/:/, $course));
-    my ($cnum,$cdom)=&get_course();
-    my %slots=&Apache::lonnet::get('slots', [@slots], $cdom, $cnum);
-    foreach my $slot_name (@slots) {
-	next if (!defined($slots{$slot_name}) ||
-		 !ref($slots{$slot_name}));
+    my ($symb,$new_slot_name,$new_slot,$slots,$consumed_uniqueperiods)=@_;
+
+    if (!defined($new_slot->{'uniqueperiod'})) { return undef; }
 
-        next if (!defined($slots{$slot_name}->{'uniqueperiod'}) ||
-		 !ref($slots{$slot_name}->{'uniqueperiod'}));
-	my ($start,$end)=@{$slots{$slot_name}->{'uniqueperiod'}};
-	if ($start<time && time < $end) {
+    if (!ref($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;
 	}
     }
@@ -172,12 +240,31 @@ sub make_reservation {
     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");   
-
-	    my $me=$env{'user.name'}.'@'.$env{'user.domain'};
+	    if (&Apache::lonnet::error($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];
@@ -191,7 +278,9 @@ sub make_reservation {
     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];
@@ -205,9 +294,9 @@ sub make_reservation {
 	return undef;
     }
     
-    my %reservation=('name'      => $env{'user.name'}.'@'.$env{'user.domain'},
+    my %reservation=('name'      => $env{'user.name'}.':'.$env{'user.domain'},
 		     'timestamp' => time,
-		     'symb'      => $symb);
+		     'symb'      => $parm_symb);
 
     my $success=&Apache::lonnet::newput('slot_reservations',
 					{"$slot_name\0$wanted" =>
@@ -221,7 +310,8 @@ sub make_reservation {
 	}
 	my $result=&Apache::lonparmset::storeparm_by_symb($symb,
 						      '0_availablestudent',
-						       1, $new_value, 'string',
+						       $parm_level, $new_value,
+						       'string',
 						       $env{'user.name'},
 					               $env{'user.domain'});
 	&Apache::lonxml::debug("hrrm $result");
@@ -232,17 +322,147 @@ sub make_reservation {
     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>".&mt('A network error has occured.').'</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)=@_;
+    my ($r,$symb,$slot_name,$inhibit_return_link,$mgr)=@_;
 
     if ($slot_name eq '') { $slot_name=$env{'form.slotname'}; }
-    my ($cnum,$cdom)=&get_course();
 
+    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",
-					       $symb,$env{'user.domain'},
-					       $env{'user.name'}));
+					       $symb,$udom,$uname));
+
     my @new_slots;
     foreach my $exist_slot (@slots) {
 	if ($exist_slot eq $slot_name) { next; }
@@ -250,37 +470,95 @@ sub release_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 
-	     ($env{'user.name'}.'@'.$env{'user.domain'}) ) {
+	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',
-						      1, $new_param, 'string',
-						      $env{'user.name'},
-						      $env{'user.domain'});
+						      $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 $description=&get_description($env{'form.slotname'},\%slot);
-    $r->print("<p>Released Reservation: $description</p>");
-    if (!$inhibit_return_link) {
-	$r->print('<p><a href="/adm/flip?postdata=return:">'.
-		  &mt('Return to last resource').'</a></p>');
+
+    my ($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 {
+	    $r->print("<p> An error ($ret) occurse when attempting to delete Slot <tt>$slot_name</tt>.</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>");
+	}
     }
-    return 1;
+    $r->print('<p><a href="/adm/slotrequest?command=showslots">'.
+	      &mt('Return to slot list').'</a></p>');
+    &return_link($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)=@_;
+    my ($r,$symb,$conflictable_slot,$inhibit_return_link)=@_;
 
-    my $slot_name=&check_for_conflict($symb,$env{'form.slotname'});
-    if ($slot_name) {
+    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>An error occured while attempting to make a reservation. ($1)</p>");
+	&return_link($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'});
@@ -288,7 +566,7 @@ sub get_slot {
 	$r->print("<p>Already have a reservation: $description1</p>");
 	if ($slot_name ne $env{'form.slotname'}) {
 	    $r->print(<<STUFF);
-<form method="POST" action="/adm/slotrequest">
+<form method="post" action="/adm/slotrequest">
    <input type="hidden" name="symb" value="$env{'form.symb'}" />
    <input type="hidden" name="slotname" value="$env{'form.slotname'}" />
    <input type="hidden" name="releaseslot" value="$slot_name" />
@@ -300,88 +578,152 @@ STUFF
 STUFF
 	    $r->print(' your reservation from <b>'.$description1.'</b> to <b>'.
 		      $description2.
-		      '</b> <br />or <a href="/adm/flip?postdata=return:">'.
-		      &mt('Return to last resource').'</a></p>');
+		      '</b> <br />or </p>');
+	    &return_link($r);
 	    $r->print(<<STUFF);
 </form>
 STUFF
         } else {
-	    $r->print('<p><a href="/adm/flip?postdata=return:">'.
-		      &mt('Return to last resource').'</a></p>');
+	    &return_link($r);
 	}
-	return;
+	return 0;
     }
-    my %slot=&Apache::lonnet::get_slot($env{'form.slotname'});
+
     my $reserved=&make_reservation($env{'form.slotname'},
 				   \%slot,$symb);
     my $description=&get_description($env{'form.slotname'},\%slot);
     if (defined($reserved)) {
-	if ($reserved > -1) {
+	my $retvalue = 0;
+	if ($slot_name =~ /^error: (.*)/) {
+	    $r->print("<p>An error occured while attempting to make a reservation. ($1)</p>");
+	} elsif ($reserved > -1) {
 	    $r->print("<p>Success: $description</p>");
-	    $r->print('<p><a href="/adm/flip?postdata=return:">'.
-		      &mt('Return to last resource').'</a></p>');
-	    return;
+	    $retvalue = 1;
 	} elsif ($reserved < 0) {
 	    $r->print("<p>Already reserved: $description</p>");
-	    $r->print('<p><a href="/adm/flip?postdata=return:">'.
-		      &mt('Return to last resource').'</a></p>');
-	    return;
 	}
+	if (!$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> <font color="red">Failed</font> to reserve a spot for $description. </p>
 <p>
-<form method="POST" action="/adm/slotrequest">
+<form method="post" action="/adm/slotrequest">
    <input type="submit" name="Try Again" value="$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="get" />
+   <input type="hidden" name="command" value="$env{'form.command'}" />
+   $extra_input
 </form>
 ?
 </p>
 <p>
 or
-<form method="POST" action="/adm/slotrequest">
+<form method="post" action="/adm/slotrequest">
     <input type="hidden" name="symb" value="$env{'form.symb'}" />
     <input type="submit" name="requestattempt" value="$lt{'request'}" />
 </form>
 </p>
 or
 STUFF
-    $r->print('<p><a href="/adm/flip?postdata=return:">'.
-	      &mt('Return to last resource').'</a></p>');
-    return;
+
+    if (!$inhibit_return_link) { &return_link($r); }
+    return 0;
 }
 
 sub allowed_slot {
-    my ($slot_name,$slot,$symb)=@_;
+    my ($slot_name,$slot,$symb,$slots,$consumed_uniqueperiods)=@_;
+
     #already started
     if ($slot->{'starttime'} < time) {
 	# all open slot to be schedulable
-	#return 0;
+	return 0;
     }
     &Apache::lonxml::debug("$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;
 }
@@ -402,33 +744,43 @@ sub show_choices {
 
     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_slot)=&check_for_reservation($symb);
+    my @got_slots=&check_for_reservation($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}));
+	next if (!&allowed_slot($slot,$slots{$slot},undef,\%slots,
+				$consumed_uniqueperiods));
 
 	$available++;
 
 	my $description=&get_description($slot,$slots{$slot});
 
 	my $form=&mt('Unavailable');
-	if (($slot eq $got_slot) ||
+	if ((grep(/^\Q$slot\E$/,@got_slots)) ||
 	    &space_available($slot,$slots{$slot},$symb)) {
 	    my $text=&mt('Select');
 	    my $command='get';
-	    if ($slot eq $got_slot) {
-		$text=&mt('Free Reservation');
+	    if (grep(/^\Q$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 $escsymb=&Apache::lonnet::escape($symb);
+	    my $escsymb=&escape($symb);
 	    $form=<<STUFF;
-   <form method="POST" action="/adm/slotrequest">
+   <form method="post" action="/adm/slotrequest">
      <input type="submit" name="Select" value="$text" />
      <input type="hidden" name="symb" value="$escsymb" />
      <input type="hidden" name="slotname" value="$slot" />
@@ -451,73 +803,481 @@ STUFF
     $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 ($r,$symb,$mgr)=@_;
+    my ($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') {
-	$r->print('<form method="POST" action="/adm/slotrequest">
+    # 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>');
+	$r->print('<form method="post" action="/adm/slotrequest">
 <input type="hidden" name="command" value="uploadstart" />
-<input type="hidden" name="symb" value="'.$env{'form.symb'}.'" />
 <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>');
     }
-    $r->print('<table border="1">
-<tr>
-  <th>Slot name</th>
-  <th>Type</th>
-  <th>Description</th>
-  <th>Start Time</th>
-  <th>End Time</th>
-  <th>Max space</th>
-  <th>Scheduled Students</th>
-  <th>Proctors</th>
-  <th>Unique Period</th>
-</tr>');
-    foreach my $slot (sort 
-		      { return $slots{$a}->{'starttime'} <=> $slots{$b}->{'starttime'} }
-		      (keys(%slots)))  {
+    
+    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 %consumed=&Apache::lonnet::dump('slot_reservations',$cdom,$cnum,
-					   "^$slot\0");
-	my $ids;
-	foreach my $entry (sort(keys(%consumed))) {
-	    my (undef,$id)=split("\0",$entry);
-	    $ids.= $id.'-> '.$consumed{$entry}->{'name'}.'<br />';
+	my ($id_count,$ids);
+	    
+	if (exists($show{'scheduled'}) || exists($show{'space'}) ) {
+	    my @this_slot = grep(/^$slot\0/,keys(%consumed));
+	    $id_count = scalar(@this_slot);
+	    if (exists($show{'scheduled'})) {
+		foreach my $entry (sort { $consumed{$a}{name} cmp 
+					      $consumed{$b}{name} }
+				   (keys(%consumed))) {
+		    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 $start=localtime($slots{$slot}->{'starttime'});
-	my $end=localtime($slots{$slot}->{'endtime'});
+
+	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]).','.
+	    $unique=localtime($slots{$slot}{'uniqueperiod'}[0]).', '.
 		localtime($slots{$slot}{'uniqueperiod'}[1]);
 	}
 
-	$r->print(<<STUFF);
-<tr>
- <td>$slot</td>
- <td>$slots{$slot}->{'type'}</td>
- <td>$description</td>
- <td>$start</td>
- <td>$end</td>
- <td>$slots{$slot}->{'maxspace'}</td>
- <td>$ids</td>
- <td>$slots{$slot}->{'proctor'}</td>
- <td>$unique</td>
-</tr>
+	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>');
+    $r->print('</table></form>');
 }
 
 sub upload_start {
-    my ($r,$symb)=@_;    
+    my ($r)=@_;    
     $r->print(&Apache::grades::checkforfile_js());
     my $result.='<table width=100% border=0><tr bgcolor="#e6ffff"><td>'."\n";
     $result.='&nbsp;<b>'.
@@ -528,7 +1288,6 @@ sub upload_start {
     my $ignore=&mt('Ignore First Line');
     $result.=<<ENDUPFORM;
 <form method="post" enctype="multipart/form-data" action="/adm/slotrequest" name="slotupload">
-<input type="hidden" name="symb" value="$symb" />
 <input type="hidden" name="command" value="csvuploadmap" />
 $upfile_select
 <br /><input type="button" onClick="javascript:checkUpload(this.form);" value="Upload Data" />
@@ -541,7 +1300,7 @@ ENDUPFORM
 }
 
 sub csvuploadmap_header {
-    my ($r,$symb,$datatoken,$distotal)= @_;
+    my ($r,$datatoken,$distotal)= @_;
     my $javascript;
     if ($env{'form.upfile_associate'} eq 'reverse') {
 	$javascript=&csvupload_javascript_reverse_associate();
@@ -551,9 +1310,11 @@ sub csvuploadmap_header {
 
     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</h3>
+<h3>Identify fields $help_field</h3>	
 Total number of records found in file: $distotal <hr />
 Enter as many fields as you can. The system will inform you and bring you back
 to this page if the data selected is insufficient to create the slots.<hr />
@@ -565,7 +1326,6 @@ to this page if the data selected is ins
 <input type="hidden" name="upfiletype" value="$env{'form.upfiletype'}" />
 <input type="hidden" name="upfile_associate" 
                                        value="$env{'form.upfile_associate'}" />
-<input type="hidden" name="symb"       value="$symb" />
 <input type="hidden" name="command"    value="csvuploadassign" />
 <hr />
 <script type="text/javascript" language="Javascript">
@@ -640,7 +1400,7 @@ ENDPICK
 }
 
 sub csv_upload_map {
-    my ($r,$symb)= @_;
+    my ($r)= @_;
 
     my $datatoken;
     if (!$env{'form.datatoken'}) {
@@ -651,7 +1411,7 @@ sub csv_upload_map {
     }
     my @records=&Apache::loncommon::upfile_record_sep();
     if ($env{'form.noFirstLine'}) { shift(@records); }
-    &csvuploadmap_header($r,$symb,$datatoken,$#records+1);
+    &csvuploadmap_header($r,$datatoken,$#records+1);
     my ($i,$keyfields);
     if (@records) {
 	my @fields=&csvupload_fields();
@@ -687,11 +1447,14 @@ sub csvupload_fields {
 	    ['maxspace','Maximum number of reservations'],
 	    ['symb','Resource Restriction'],
 	    ['uniqueperiod','Date range of slot exclusion'],
-	    ['secret','Secret word proctor uses to validate']);
+	    ['secret','Secret word proctor uses to validate'],
+	    ['allowedsections','Sections slot is restricted to'],
+	    ['allowedusers','Users slot is restricted to'],
+	    );
 }
 
 sub csv_upload_assign {
-    my ($r,$symb,$mgr)= @_;
+    my ($r,$mgr)= @_;
     &Apache::loncommon::load_tmp_file($r);
     my @slotdata = &Apache::loncommon::upfile_record_sep();
     if ($env{'form.noFirstLine'}) { shift(@slotdata); }
@@ -700,79 +1463,162 @@ sub csv_upload_assign {
     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("<br />Created $countdone slots\n");
-    $r->print("<br />\n");
-    &show_table($r,$symb,$mgr);
+    $r->print("<p>Created $countdone slots\n</p>");
+    foreach my $error (@errors) {
+	$r->print("<p>$error\n</p>");
+    }
+    &show_table($r,$mgr);
     return '';
 }
 
 sub handler {
     my $r=shift;
 
-    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'});
-    &start_page($r);
-    my $symb=&Apache::lonnet::unescape($env{'form.symb'});
-    my (undef,undef,$res)=&Apache::lonnet::decode_symb($symb);
-    if ($res !~ /\.task$/) {
-	&fail($r,'not_valid');
+    &Apache::loncommon::content_type($r,'text/html');
+    &Apache::loncommon::no_cache($r);
+    if ($r->header_only()) {
+	$r->send_http_header();
 	return OK;
     }
-    $env{'request.symb'}=$symb;
+
+    &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,$symb,$mgr);
+	&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,$symb);
+	&upload_start($r);
     } elsif ($env{'form.command'} eq 'csvuploadmap' && $mgr eq 'F') {
-	&csv_upload_map($r,$symb);
+	&csv_upload_map($r);
     } elsif ($env{'form.command'} eq 'csvuploadassign' && $mgr eq 'F') {
 	if ($env{'form.associate'} ne 'Reverse Association') {
-	    &csv_upload_assign($r,$symb,$mgr);
+	    &csv_upload_assign($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,$symb);
+	    &csv_upload_map($r);
 	}
     } else {
-	my ($status) = &Apache::lonhomework::check_task_access('0');
+	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' ||
 	    $status eq 'WAITING_FOR_GRADE') {
@@ -786,8 +1632,9 @@ sub handler {
 	} elsif ($env{'form.command'} eq 'get') {
 	    &get_slot($r,$symb);
 	} elsif ($env{'form.command'} eq 'change') {
-	    &release_slot($r,$symb,$env{'form.releaseslot'},1);
-	    &get_slot($r,$symb);
+	    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>");
 	}