--- loncom/homework/essayresponse.pm	2001/06/02 03:59:59	1.3
+++ loncom/homework/essayresponse.pm	2002/07/25 20:51:39	1.11
@@ -1,33 +1,114 @@
 # The LearningOnline Network with CAPA
 # essay (ungraded) style responses
+#
+# $Id: essayresponse.pm,v 1.11 2002/07/25 20:51:39 ng 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/
+#
 # 4/3 Guy
+# July, 2002, H. K. Ng
+#
 package Apache::essayresponse;
 use strict;
 
-sub BEGIN {
-  &Apache::lonxml::register('Apache::essayresponse',('essayresponse'));
+BEGIN {
+    &Apache::lonxml::register('Apache::essayresponse',('essayresponse'));
 }
 
 sub start_essayresponse {
-  my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
-  my $id = &Apache::response::start_response($parstack,$safeeval);
-  return '';
+    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
+    my $result;
+
+    if ($target eq 'web') {
+	my $part= $Apache::inputtags::part;
+	my $id  = &Apache::response::start_response($parstack,$safeeval);
+
+	my $ncol= &Apache::lonnet::EXT("resource.$part".'_'."$id.maxcollaborators");
+	my $coll= &HTML::Entities::encode($Apache::lonhomework::history{"resource.$part.$id.collaborators"});
+	if ($ncol > 0) {
+	    $result .='<br />Collaborators: <input type="text" size="70" max="80" name="HWCOL'.
+		$id.'" value="'.$coll.'" /><br />'.
+		'(Enter maximum '.$ncol.' collaborators using username or username@domain, e.g. '.
+		'smithje or smithje@'.$ENV{'user.domain'}.'.)<br />';
+	    $result .= &check_collaborators($ncol,$coll) if ($coll =~ /\w+/);
+	}
+    }
+    return $result;
 }
 
 sub end_essayresponse {
-  my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
-  if ( $target eq 'grade' ) {
-    if ( defined $ENV{'form.submitted'}) {
-      my $id = $Apache::inputtags::response['-1'];
-      my $response = $ENV{'form.HWVAL'.$Apache::inputtags::response['-1']};
-      if ( $response =~ /[^\s]/) {
-	$Apache::lonhomework::results{"resource.$Apache::inputtags::part.$id.submission"}=$response;
-	$Apache::lonhomework::results{"resource.$Apache::inputtags::part.$id.awarddetail"}="SUBMITTED";
-      }
-    }
-  }
-  &Apache::response::end_response;
-  return '';
+    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
+    my $part=$Apache::inputtags::part;
+    my $id  = &Apache::response::start_response($parstack,$safeeval);
+    my $collaborators = $ENV{'form.HWCOL'.$id};	
+    if ($collaborators =~ /[^\s]/) {
+	$Apache::lonhomework::results{"resource.$part.$id.collaborators"}=$collaborators;
+    }
+    if ( $target eq 'grade' ) {
+	if ( defined $ENV{'form.submitted'}) {
+	    my $response      = $ENV{'form.HWVAL'.$id};
+	    if ( $response =~ /[^\s]/) {
+		$Apache::lonhomework::results{"resource.$part.$id.submission"}=$response;
+		$Apache::lonhomework::results{"resource.$part.$id.awarddetail"}="SUBMITTED";
+		my %previous=&Apache::response::check_for_previous($response,$part,$id);
+		&Apache::response::handle_previous(\%previous,'SUBMITTED');
+	    }
+	}
+    }
+
+    &Apache::response::end_response;
+    return '';
+}
+
+sub check_collaborators {
+    my ($ncol,$coll) = @_;
+    my %classlist=&Apache::lonnet::dump('classlist',
+					$ENV{'course.'.$ENV{'request.course.id'}.'.domain'},
+					$ENV{'course.'.$ENV{'request.course.id'}.'.num'});
+    my (@badcollaborators,$result);
+    my (@collaborators) = split(/\,?\s+/,$coll);
+    foreach (@collaborators) {
+	my $collaborator = $_;
+	if (/@/) {
+	    $collaborator =~ s/@/:/;
+	} else {
+	    $collaborator = $_.':'.$ENV{'user.domain'};
+	}
+	push @badcollaborators, $_ if (!grep /^$collaborator/i,keys %classlist);
+    }
+    
+    if (scalar(@badcollaborators)) {
+	$result = '<table border="0"><tr bgcolor="#ffbbbb"><td> The following user'.
+	    (scalar(@badcollaborators) > 1 ? 's are' : ' is').' invalid: '.
+	    join(', ',@badcollaborators).'. Please correct.</td></tr></table>';
+    }
+    my $toomany = scalar(@collaborators) - $ncol;
+    if ($toomany > 0) {
+	$result .= '<table border="0"><tr bgcolor="#ffbbbb"><td>'.
+	    'You have too many collaborators. Please remove '.$toomany.' collaborator'.
+	    ($toomany > 1 ? 's' :'').'.</td></tr></table>';
+    }
+    return $result;
 }
 
 1;