--- loncom/interface/slotrequest.pm	2005/08/09 15:04:50	1.6
+++ loncom/interface/slotrequest.pm	2005/10/17 18:23:46	1.23
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Handler for requesting to have slots added to a students record
 #
-# $Id: slotrequest.pm,v 1.6 2005/08/09 15:04:50 albertel Exp $
+# $Id: slotrequest.pm,v 1.23 2005/10/17 18:23:46 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -34,13 +34,19 @@ use Apache::Constants qw(:common :http :
 use Apache::loncommon();
 use Apache::lonlocal;
 use Apache::lonnet;
+use Date::Manip;
 
 sub fail {
     my ($r,$code)=@_;
     if ($code eq 'not_valid') {
-	$r->print('<p>'.&mt('Unable to understand what resource you wanted to sign up for.').'</p>'.$env{'form.symb'});
+	$r->print('<p>'.&mt('Unable to understand what resource you wanted to sign up for.').'</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>');
     }
+    
     $r->print('<p><a href="/adm/flip?postdata=return:">'.
 	      &mt('Return to last resource').'</a></p>');
     &end_page($r);
@@ -125,9 +131,9 @@ sub check_for_reservation {
 	&Apache::lonxml::debug(time." $slot_name ".
 			       $slots{$slot_name}->{'starttime'}." -- ".
 			       $slots{$slot_name}->{'startreserve'});
-	if ($slots{$slot_name}->{'starttime'} > time &&
+	if ($slots{$slot_name}->{'endtime'} > time &&
 	    $slots{$slot_name}->{'startreserve'} < time) {
-	    # between start of reservation times and start of slot
+	    # between start of reservation times and end of slot
 	    return($slot_name, $slots{$slot_name});
 	}
     }
@@ -158,9 +164,6 @@ sub check_for_conflict {
 
 }
 
-# FIXME - depends on the parameter for the resource to be correct
-#         to prevent multiple reservations
-
 sub make_reservation {
     my ($slot_name,$slot,$symb)=@_;
 
@@ -189,7 +192,6 @@ sub make_reservation {
 
     my (@ids)=&get_reservation_ids($slot_name);
 
-    # FIXME we could end up having holes... 
     my $last=0;
     foreach my $id (@ids) {
 	my $num=(split('\0',$id))[1];
@@ -198,9 +200,9 @@ sub make_reservation {
     
     my $wanted=$last+1;
     &Apache::lonxml::debug("wanted $wanted<br />");
-    if ($wanted >= $max) {
+    if (scalar(@ids) >= $max) {
 	# full up
-	return -1;
+	return undef;
     }
     
     my %reservation=('name'      => $env{'user.name'}.'@'.$env{'user.domain'},
@@ -213,7 +215,6 @@ sub make_reservation {
 					$cdom, $cnum);
 
     if ($success eq 'ok') {
-	#FIXME need to set the parm
 	my $new_value=$slot_name;
 	if ($value) {
 	    $new_value=$value.':'.$new_value;
@@ -268,7 +269,7 @@ sub release_slot {
     my %slot=&Apache::lonnet::get_slot($slot_name);
     my $description=&get_description($env{'form.slotname'},\%slot);
     $r->print("<p>Released Reservation: $description</p>");
-    if ($inhibit_return_link) {
+    if (!$inhibit_return_link) {
 	$r->print('<p><a href="/adm/flip?postdata=return:">'.
 		  &mt('Return to last resource').'</a></p>');
     }
@@ -285,44 +286,50 @@ sub get_slot {
 	%slot=&Apache::lonnet::get_slot($env{'form.slotname'});
 	my $description2=&get_description($env{'form.slotname'},\%slot);
 	$r->print("<p>Already have a reservation: $description1</p>");
-	$r->print(<<STUFF);
+	if ($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);
+            $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 <a href="/adm/flip?postdata=return:">'.
-		  &mt('Return to last resource').'</a></p>');
-	$r->print(<<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>');
+	    $r->print(<<STUFF);
 </form>
 STUFF
-	# FIXME add button to free current reservation and get new one
+        } else {
+	    $r->print('<p><a href="/adm/flip?postdata=return:">'.
+		      &mt('Return to last resource').'</a></p>');
+	}
 	return;
     }
     my %slot=&Apache::lonnet::get_slot($env{'form.slotname'});
     my $reserved=&make_reservation($env{'form.slotname'},
 				   \%slot,$symb);
     my $description=&get_description($env{'form.slotname'},\%slot);
-    if ($reserved > -1) {
-	$r->print("<p>Success: $description</p>");
-	$r->print('<p><a href="/adm/flip?postdata=return:">'.
-		  &mt('Return to last resource').'</a></p>');
-	return;
-    } elsif ($reserved < 0) {
-	$r->print("<p>Already reserved: $description</p>");
-	$r->print('<p><a href="/adm/flip?postdata=return:">'.
-		  &mt('Return to last resource').'</a></p>');
-	return;
+    if (defined($reserved)) {
+	if ($reserved > -1) {
+	    $r->print("<p>Success: $description</p>");
+	    $r->print('<p><a href="/adm/flip?postdata=return:">'.
+		      &mt('Return to last resource').'</a></p>');
+	    return;
+	} elsif ($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;
+	}
     }
 
-    my %lt=('request'=>"Request another attempt",
+    my %lt=('request'=>"Availibility list",
 	    'try'    =>'Try again');
     %lt=&Apache::lonlocal::texthash(%lt);
 
@@ -411,7 +418,8 @@ sub show_choices {
 	my $description=&get_description($slot,$slots{$slot});
 
 	my $form=&mt('Unavailable');
-	if (&space_available($slot,$slots{$slot},$symb)) {
+	if (($slot eq $got_slot) ||
+	    &space_available($slot,$slots{$slot},$symb)) {
 	    my $text=&mt('Select');
 	    my $command='get';
 	    if ($slot eq $got_slot) {
@@ -444,18 +452,66 @@ STUFF
 }
 
 sub show_table {
-    my ($r,$symb)=@_;
+    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;
-    $r->print('<table border="1">');
-    foreach my $slot (sort 
-		      { return $slots{$a}->{'starttime'} <=> $slots{$b}->{'starttime'} }
-		      (keys(%slots)))  {
+    if ($mgr eq 'F') {
+	$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>');
+    }
+    my $linkstart='<a href="/adm/slotrequest?command=showslots&amp;order=';
+    $r->print('<table border="1">
+<tr>
+  <th></th>
+  <th>'.$linkstart.'name"        >Slot name</a></th>
+  <th>'.$linkstart.'type"        >Type</a></th>
+  <th>'.$linkstart.'description" >Description</a></th>
+  <th>'.$linkstart.'starttime"   >Start Time</a></th>
+  <th>'.$linkstart.'endtime"     >End Time</a></th>
+  <th>'.$linkstart.'startreserve">Time Students Can Start Reserving</a></th>
+  <th>'.$linkstart.'secret"      >Secret</a></th>
+  <th>'.$linkstart.'maxspace"    >Max space</a></th>
+  <th>                            Scheduled Students</th>
+  <th>'.$linkstart.'unique"      >Unique Period</a></th>
+</tr>');
+    my %name_cache;
+    my $slotsort = sub {
+	if ($env{'form.order'}=~/^(type|description|endtime|maxspace)$/) {
+	    if (lc($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 'name') {
+	    if (lc($a) cmp lc($b)) {
+		return lc($a) cmp lc($b);
+	    }
+	} elsif ($env{'form.order'} eq 'unique') {
+	    
+	    if ($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'};
+    };
+    foreach my $slot (sort $slotsort (keys(%slots)))  {
 	if (defined($slots{$slot}->{'type'})
 	    && $slots{$slot}->{'type'} ne 'schedulable_student') {
-	    next;
+	    #next;
 	}
 	my $description=&get_description($slot,$slots{$slot});
 	my %consumed=&Apache::lonnet::dump('slot_reservations',$cdom,$cnum,
@@ -465,44 +521,336 @@ sub show_table {
 	    my (undef,$id)=split("\0",$entry);
 	    $ids.= $id.'-> '.$consumed{$entry}->{'name'}.'<br />';
 	}
-	my $start=localtime($slots{$slot}->{'starttime'});
-	my $end=localtime($slots{$slot}->{'endtime'});
+	my $start=&Apache::lonlocal::locallocaltime($slots{$slot}->{'starttime'});
+	my $end=&Apache::lonlocal::locallocaltime($slots{$slot}->{'endtime'});
+	my $start_reserve=&Apache::lonlocal::locallocaltime($slots{$slot}->{'startreserve'});
+	my $unique;
+	if (ref($slots{$slot}{'uniqueperiod'})) {
+	    $unique=localtime($slots{$slot}{'uniqueperiod'}[0]).','.
+		localtime($slots{$slot}{'uniqueperiod'}[1]);
+	}
+	my @proctors = map {
+	    my ($uname,$udom)=split(/@/,$_);
+	    my $fullname=$name_cache{$_};
+	    if (!defined($fullname)) {
+		&Apache::lonnet::logthis("Gettign $uname $udom");
+		$fullname = &Apache::loncommon::plainname($uname,$udom);
+		$fullname =~s/\s/&nbsp;/g;
+		$name_cache{$_} = $fullname;
+	    }
+	    &Apache::loncommon::aboutmewrapper($fullname,$uname,$udom);
+	} (split(/\s*,\s*/,$slots{$slot}->{'proctor'}));
+	
+	my $proctors=join(', ',@proctors);
+
+	my $edit=(<<EDITFORM);
+<form method="POST">
+  <input type="hidden" name="command" value="editslot" />
+  <input type="hidden" name="slot" value="$slot" />
+  <input type="submit" name="Edit" value="Edit" />
+</form>
+EDITFORM
 	$r->print(<<STUFF);
 <tr>
+ <td rowspan="2">$edit</td>
  <td>$slot</td>
+ <td>$slots{$slot}->{'type'}</td>
  <td>$description</td>
  <td>$start</td>
  <td>$end</td>
+ <td>$start_reserve</td>
+ <td>$slots{$slot}->{'secret'}</td>
  <td>$slots{$slot}->{'maxspace'}</td>
  <td>$ids</td>
+ <td>$unique</td>
+</tr>
+<tr>
+ <td colspan="10">$proctors</td>
 </tr>
 STUFF
     }
     $r->print('</table>');
 }
 
+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');
+    $r->print(<<ENDPICK);
+<form method="post" enctype="multipart/form-data" action="/adm/slotrequest" name="slotupload">
+<h3>Identify fields</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']);
+}
+
+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;
+    foreach my $slot (@slotdata) {
+	my %slot;
+	my %entries=&Apache::loncommon::record_sep($slot);
+	my $domain;
+	my $name=$entries{$fields{'name'}};
+	if ($entries{$fields{'type'}}) {
+	    $slot{'type'}=$entries{$fields{'type'}};
+	} else {
+	    $slot{'type'}='preassigned';
+	}
+	if ($entries{$fields{'starttime'}}) {
+	    $slot{'starttime'}=&UnixDate($entries{$fields{'starttime'}},"%s");
+	}
+	if ($entries{$fields{'endtime'}}) {
+	    $slot{'endtime'}=&UnixDate($entries{$fields{'endtime'}},"%s");
+	}
+	if ($entries{$fields{'startreserve'}}) {
+	    $slot{'startreserve'}=
+		&UnixDate($entries{$fields{'startreserve'}},"%s");
+	}
+	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"));
+	    $slot{'uniqueperiod'}=\@times;
+	}
+
+	&Apache::lonnet::cput('slots',{$name=>\%slot},$cdom,$cname);
+	$r->print('.');
+	$r->rflush();
+	$countdone++;
+    }
+    $r->print("<br />Created $countdone slots\n");
+    $r->print("<br />\n");
+    &show_table($r,$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($r,'not_valid');
-	return OK;
-    }
- 
-    if ($env{'form.command'} eq 'showslots') {
-	&show_table($r,$symb);
-    } elsif ($env{'form.requestattempt'}) {
-	&show_choices($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') {
-       	&release_slot($r,$symb,$env{'form.releaseslot'},1);
-	&get_slot($r,$symb);
+    my $vgr=&Apache::lonnet::allowed('vgr',$env{'request.course.id'});
+    my $mgr=&Apache::lonnet::allowed('mgr',$env{'request.course.id'});
+    if ($env{'form.command'} eq 'showslots' && $vgr eq 'F') {
+	&show_table($r,$mgr);
+    } elsif ($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);
+	}
+    } elsif ($env{'form.command'} eq 'editslot' && $mgr eq 'F') {
+	&show_slot_edit($r);
+    } else {
+	my $symb=&Apache::lonnet::unescape($env{'form.symb'});
+	my (undef,undef,$res)=&Apache::lonnet::decode_symb($symb);
+	if ($res !~ /\.task$/) {
+	    &fail($r,'not_valid');
+	    return OK;
+	}
+	$env{'request.symb'}=$symb;
+	my ($status) = &Apache::lonhomework::check_task_access('0');
+	if ($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') {
+	    &release_slot($r,$symb,$env{'form.releaseslot'},1);
+	    &get_slot($r,$symb);
+	} else {
+	    $r->print("<p>Unknown command: ".$env{'form.command'}."</p>");
+	}
     }
     &end_page($r);
     return OK;