--- loncom/interface/loncommon.pm	2003/02/13 21:35:50	1.80
+++ loncom/interface/loncommon.pm	2003/08/13 20:40:31	1.111
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # a pile of common routines
 #
-# $Id: loncommon.pm,v 1.80 2003/02/13 21:35:50 albertel Exp $
+# $Id: loncommon.pm,v 1.111 2003/08/13 20:40:31 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -79,8 +79,9 @@ use strict;
 use Apache::lonnet();
 use GDBM_File;
 use POSIX qw(strftime mktime);
-use Apache::Constants qw(:common);
+use Apache::Constants qw(:common :http :methods);
 use Apache::lonmsg();
+use Apache::lonmenu();
 my $readit;
 
 =pod 
@@ -150,8 +151,8 @@ BEGIN {
 	    while (<$fh>) {
 		next if /^\#/;
 		chomp;
-		my ($key,$val)=(split(/\s+/,$_,2));
-		$language{$key}=$val;
+		my ($key,$two,$country,$three,$enc,$val)=(split(/\t/,$_));
+		$language{$key}=$val.' - '.$enc;
 	    }
 	}
     }
@@ -310,14 +311,15 @@ END
 }
 
 sub studentbrowser_javascript {
-   unless ($ENV{'request.course.id'}) { return ''; }  
-   unless (&Apache::lonnet::allowed('srm',$ENV{'request.course.id'})) {
-        return '';
-   }
+   unless (
+            (($ENV{'request.course.id'}) && 
+             (&Apache::lonnet::allowed('srm',$ENV{'request.course.id'})))
+         || ($ENV{'request.role'}=~/^(au|dc|su)/)
+          ) { return ''; }  
    return (<<'ENDSTDBRW');
 <script type="text/javascript" language="Javascript" >
     var stdeditbrowser;
-    function openstdbrowser(formname,uname,udom) {
+    function openstdbrowser(formname,uname,udom,roleflag) {
         var url = '/adm/pickstudent?';
         var filter;
         eval('filter=document.'+formname+'.'+uname+'.value;');
@@ -328,7 +330,8 @@ sub studentbrowser_javascript {
         }
         url += 'form=' + formname + '&unameelement='+uname+
                                     '&udomelement='+udom;
-        var title = 'Student Browser';
+	if (roleflag) { url+="&roles=1"; }
+        var title = 'Student_Browser';
         var options = 'scrollbars=1,resizable=1,menubar=0';
         options += ',width=700,height=600';
         stdeditbrowser = open(url,title,options,'1');
@@ -339,13 +342,49 @@ ENDSTDBRW
 }
 
 sub selectstudent_link {
-    my ($form,$unameele,$udomele)=@_;
-   unless ($ENV{'request.course.id'}) { return ''; }  
-   unless (&Apache::lonnet::allowed('srm',$ENV{'request.course.id'})) {
-        return '';
+   my ($form,$unameele,$udomele)=@_;
+   if ($ENV{'request.course.id'}) {  
+       unless (&Apache::lonnet::allowed('srm',$ENV{'request.course.id'})) {
+	   return '';
+       }
+       return "<a href='".'javascript:openstdbrowser("'.$form.'","'.$unameele.
+        '","'.$udomele.'");'."'>Select User</a>";
+   }
+   if ($ENV{'request.role'}=~/^(au|dc|su)/) {
+       return "<a href='".'javascript:openstdbrowser("'.$form.'","'.$unameele.
+        '","'.$udomele.'",1);'."'>Select User</a>";
    }
-    return "<a href='".'javascript:openstdbrowser("'.$form.'","'.$unameele.
-        '","'.$udomele.'");'."'>Select</a>";
+   return '';
+}
+
+sub coursebrowser_javascript {
+   return (<<'ENDSTDBRW');
+<script type="text/javascript" language="Javascript" >
+    var stdeditbrowser;
+    function opencrsbrowser(formname,uname,udom) {
+        var url = '/adm/pickcourse?';
+        var filter;
+        if (filter != null) {
+           if (filter != '') {
+               url += 'filter='+filter+'&';
+	   }
+        }
+        url += 'form=' + formname + '&cnumelement='+uname+
+                                    '&cdomelement='+udom;
+        var title = 'Course_Browser';
+        var options = 'scrollbars=1,resizable=1,menubar=0';
+        options += ',width=700,height=600';
+        stdeditbrowser = open(url,title,options,'1');
+        stdeditbrowser.focus();
+    }
+</script>
+ENDSTDBRW
+}
+
+sub selectcourse_link {
+   my ($form,$unameele,$udomele)=@_;
+    return "<a href='".'javascript:opencrsbrowser("'.$form.'","'.$unameele.
+        '","'.$udomele.'");'."'>Select Course</a>";
 }
 
 ###############################################################
@@ -518,7 +557,8 @@ sub help_open_topic {
     my ($topic, $text, $stayOnPage, $width, $height) = @_;
     $text = "" if (not defined $text);
     $stayOnPage = 0 if (not defined $stayOnPage);
-    if ($ENV{'browser.interface'} eq 'textual') {
+    if ($ENV{'browser.interface'} eq 'textual' ||
+	$ENV{'environment.remote'} eq 'off' ) {
 	$stayOnPage=1;
     }
     $width = 350 if (not defined $width);
@@ -555,6 +595,26 @@ ENDTEMPLATE
 
 }
 
+# This is a quicky function for Latex cheatsheet editing, since it 
+# appears in at least four places
+sub helpLatexCheatsheet {
+    my $other = shift;
+    my $addOther = '';
+    if ($other) {
+	$addOther = Apache::loncommon::help_open_topic($other, shift,
+						       undef, undef, 600) .
+							   '</td><td>';
+    }
+    return '<table><tr><td>'.
+	$addOther .
+	&Apache::loncommon::help_open_topic("Greek_Symbols",'Greek Symbols',
+					    undef,undef,600)
+	.'</td><td>'.
+	&Apache::loncommon::help_open_topic("Other_Symbols",'Other Symbols',
+					    undef,undef,600)
+	.'</td></tr></table>';
+}
+
 =pod
 
 =item csv_translate($text) 
@@ -600,18 +660,48 @@ sub get_domains {
 
 =pod
 
-=item select_dom_form($defdom,$name)
+=item select_form($defdom,$name,%hash)
+
+Returns a string containing a <select name='$name' size='1'> form to 
+allow a user to select options from a hash option_name => displayed text.  
+See lonrights.pm for an example invocation and use.
+
+=cut
+
+#-------------------------------------------
+sub select_form {
+    my ($def,$name,%hash) = @_;
+    my $selectform = "<select name=\"$name\" size=\"1\">\n";
+    foreach (sort keys %hash) {
+        $selectform.="<option value=\"$_\" ".
+            ($_ eq $def ? 'selected' : '').
+                ">".$hash{$_}."</option>\n";
+    }
+    $selectform.="</select>";
+    return $selectform;
+}
+
+
+#-------------------------------------------
+
+=pod
+
+=item select_dom_form($defdom,$name,$includeempty)
 
 Returns a string containing a <select name='$name' size='1'> form to 
 allow a user to select the domain to preform an operation in.  
 See loncreateuser.pm for an example invocation and use.
 
+If the $includeempty flag is set, it also includes an empty choice ("no domain
+selected");
+
 =cut
 
 #-------------------------------------------
 sub select_dom_form {
-    my ($defdom,$name) = @_;
+    my ($defdom,$name,$includeempty) = @_;
     my @domains = get_domains();
+    if ($includeempty) { @domains=('',@domains); }
     my $selectdomain = "<select name=\"$name\" size=\"1\">\n";
     foreach (@domains) {
         $selectdomain.="<option value=\"$_\" ".
@@ -673,6 +763,75 @@ sub home_server_option_list {
 ###############################################################
 
 ###############################################################
+###############################################################
+
+=pod
+
+=item &decode_user_agent()
+
+Inputs: $r
+
+Outputs:
+
+=over 4
+
+=item $httpbrowser
+
+=item $clientbrowser
+
+=item $clientversion
+
+=item $clientmathml
+
+=item $clientunicode
+
+=item $clientos
+
+=back
+
+=cut
+
+###############################################################
+###############################################################
+sub decode_user_agent {
+    my @browsertype=split(/\&/,$Apache::lonnet::perlvar{"lonBrowsDet"});
+    my %mathcap=split(/\&/,$$Apache::lonnet::perlvar{"lonMathML"});
+    my $httpbrowser=$ENV{"HTTP_USER_AGENT"};
+    my $clientbrowser='unknown';
+    my $clientversion='0';
+    my $clientmathml='';
+    my $clientunicode='0';
+    for (my $i=0;$i<=$#browsertype;$i++) {
+        my ($bname,$match,$notmatch,$vreg,$minv,$univ)=split(/\:/,$browsertype[$i]);
+	if (($httpbrowser=~/$match/i)  && ($httpbrowser!~/$notmatch/i)) {
+	    $clientbrowser=$bname;
+            $httpbrowser=~/$vreg/i;
+	    $clientversion=$1;
+            $clientmathml=($clientversion>=$minv);
+            $clientunicode=($clientversion>=$univ);
+	}
+    }
+    my $clientos='unknown';
+    if (($httpbrowser=~/linux/i) ||
+        ($httpbrowser=~/unix/i) ||
+        ($httpbrowser=~/ux/i) ||
+        ($httpbrowser=~/solaris/i)) { $clientos='unix'; }
+    if (($httpbrowser=~/vax/i) ||
+        ($httpbrowser=~/vms/i)) { $clientos='vms'; }
+    if ($httpbrowser=~/next/i) { $clientos='next'; }
+    if (($httpbrowser=~/mac/i) ||
+        ($httpbrowser=~/powerpc/i)) { $clientos='mac'; }
+    if ($httpbrowser=~/win/i) { $clientos='win'; }
+    if ($httpbrowser=~/embed/i) { $clientos='pda'; }
+    return ($httpbrowser,$clientbrowser,$clientversion,$clientmathml,
+            $clientunicode,$clientos,);
+}
+
+###############################################################
+###############################################################
+
+
+###############################################################
 ##    Authentication changing form generation subroutines    ##
 ###############################################################
 ##
@@ -1103,7 +1262,17 @@ sub get_related_words {
 ###############################################################
 
 # -------------------------------------------------------------- Plaintext name
+=pod
+
+=item plainname($uname,$udom)
+
+Gets a users name and returns it as a string in
+"first middle last generation"
+form
+
+=cut
 
+###############################################################
 sub plainname {
     my ($uname,$udom)=@_;
     my %names=&Apache::lonnet::get('environment',
@@ -1117,7 +1286,21 @@ sub plainname {
 }
 
 # -------------------------------------------------------------------- Nickname
+=pod
+
+=item nickname($uname,$udom)
+
+Gets a users name and returns it as a string as
 
+"&quot;nickname&quot;"
+
+if the user has a nickname or
+
+"first middle last generation"
+
+if the user does not
+
+=cut
 
 sub nickname {
     my ($uname,$udom)=@_;
@@ -1138,6 +1321,14 @@ sub nickname {
 
 # ------------------------------------------------------------------ Screenname
 
+=pod
+
+=item screenname($uname,$udom)
+
+Gets a users screenname and returns it as a string
+
+=cut
+
 sub screenname {
     my ($uname,$udom)=@_;
     my %names=
@@ -1170,9 +1361,11 @@ sub aboutmewrapper {
 
 
 sub syllabuswrapper {
-    my ($link,$un,$do,$tf)=@_;
-    if ($tf) { $link='<font color="'.$tf.'">'.$link.'</font>'; }
-    return "<a href='/public/$do/$un/syllabus'>$link</a>";
+    my ($linktext,$coursedir,$domain,$fontcolor)=@_;
+    if ($fontcolor) { 
+        $linktext='<font color="'.$fontcolor.'">'.$linktext.'</font>'; 
+    }
+    return "<a href='/public/$domain/$coursedir/syllabus'>$linktext</a>";
 }
 
 # ---------------------------------------------------------------- Language IDs
@@ -1185,6 +1378,32 @@ sub languagedescription {
     return $language{shift(@_)};
 }
 
+# ----------------------------------------------------------- Display Languages
+# returns a hash with all desired display languages
+#
+
+sub display_languages {
+    my %languages=();
+    if ($ENV{'environment.languages'}) {
+	foreach (split(/\s*(\,|\;|\:)\s*/,$ENV{'environment.languages'})) {
+	    $languages{$_}=1;
+        }
+    }
+    if ($ENV{'course.'.$ENV{'request.course.id'}.'.languages'}) {
+	foreach (split(/\s*(\,|\;|\:)\s*/,
+	$ENV{'course.'.$ENV{'request.course.id'}.'.languages'})) {
+	    $languages{$_}=1;
+        }
+    }
+    &get_unprocessed_cgi($ENV{'QUERY_STRING'},['displaylanguage']);
+    if ($ENV{'form.displaylanguage'}) {
+	foreach (split(/\s*(\,|\;|\:)\s*/,$ENV{'form.displaylanguage'})) {
+	    $languages{$_}=1;
+        }
+    }
+    return %languages;
+}
+
 # --------------------------------------------------------------- Copyright IDs
 sub copyrightids {
     return sort(keys(%cprtag));
@@ -1303,6 +1522,41 @@ sub get_previous_attempt {
   }
 }
 
+sub relative_to_absolute {
+    my ($url,$output)=@_;
+    my $parser=HTML::TokeParser->new(\$output);
+    my $token;
+    my $thisdir=$url;
+    my @rlinks=();
+    while ($token=$parser->get_token) {
+	if ($token->[0] eq 'S') {
+	    if ($token->[1] eq 'a') {
+		if ($token->[2]->{'href'}) {
+		    $rlinks[$#rlinks+1]=$token->[2]->{'href'};
+		}
+	    } elsif ($token->[1] eq 'img' || $token->[1] eq 'embed' ) {
+		$rlinks[$#rlinks+1]=$token->[2]->{'src'};
+	    } elsif ($token->[1] eq 'base') {
+		$thisdir=$token->[2]->{'href'};
+	    }
+	}
+    }
+    $thisdir=~s-/[^/]*$--;
+    foreach (@rlinks) {
+	unless (($_=~/^http:\/\//i) ||
+		($_=~/^\//) ||
+		($_=~/^javascript:/i) ||
+		($_=~/^mailto:/i) ||
+		($_=~/^\#/)) {
+	    my $newlocation=&Apache::lonnet::hreflocation($thisdir,$_);
+	    $output=~s/(\"|\'|\=\s*)$_(\"|\'|\s|\>)/$1$newlocation$2/;
+	}
+    }
+# -------------------------------------------------- Deal with Applet codebases
+    $output=~s/(\<applet[^\>]+)(codebase\=[^\S\>]+)*([^\>]*)\>/$1.($2?$2:' codebase="'.$thisdir.'"').$3.'>'/gei;
+    return $output;
+}
+
 sub get_student_view {
   my ($symb,$username,$domain,$courseid,$target) = @_;
   my ($map,$id,$feedurl) = split(/___/,$symb);
@@ -1314,7 +1568,8 @@ sub get_student_view {
   }
   if ($target eq 'tex') {$moreenv{'form.grade_target'} = 'tex';}
   &Apache::lonnet::appenv(%moreenv);
-  my $userview=&Apache::lonnet::ssi('/res/'.$feedurl);
+  $feedurl=&Apache::lonnet::clutter($feedurl);
+  my $userview=&Apache::lonnet::ssi_body($feedurl);
   &Apache::lonnet::delenv('form.grade_');
   foreach my $element (@elements) {
     $ENV{'form.grade_'.$element}=$old{$element};
@@ -1326,11 +1581,12 @@ sub get_student_view {
   $userview=~s/\<head\>//gi;
   $userview=~s/\<\/head\>//gi;
   $userview=~s/action\s*\=/would_be_action\=/gi;
+  $userview=&relative_to_absolute($feedurl,$userview);
   return $userview;
 }
 
 sub get_student_answers {
-  my ($symb,$username,$domain,$courseid) = @_;
+  my ($symb,$username,$domain,$courseid,%form) = @_;
   my ($map,$id,$feedurl) = split(/___/,$symb);
   my (%old,%moreenv);
   my @elements=('symb','courseid','domain','username');
@@ -1340,7 +1596,7 @@ sub get_student_answers {
   }
   $moreenv{'form.grade_target'}='answer';
   &Apache::lonnet::appenv(%moreenv);
-  my $userview=&Apache::lonnet::ssi('/res/'.$feedurl);
+  my $userview=&Apache::lonnet::ssi('/res/'.$feedurl,%form);
   &Apache::lonnet::delenv('form.grade_');
   foreach my $element (@elements) {
     $ENV{'form.grade_'.$element}=$old{$element};
@@ -1449,8 +1705,10 @@ sub domainlogo {
     my $domain = &determinedomain(shift);    
      # See if there is a logo
     if (-e '/home/httpd/html/adm/lonDomLogos/'.$domain.'.gif') {
-        return '<img src="http://'.$ENV{'HTTP_HOST'}.':8080/adm/lonDomLogos/'.
-               $domain.'.gif" />';
+	my $lonhttpdPort=$Apache::lonnet::perlvar{'lonhttpdPort'};
+	if (!defined($lonhttpdPort)) { $lonhttpdPort='8080'; }
+        return '<img src="http://'.$ENV{'HTTP_HOST'}.':'.$lonhttpdPort.
+	    '/adm/lonDomLogos/'.$domain.'.gif" />';
     } elsif(exists($Apache::lonnet::domaindescription{$domain})) {
         return $Apache::lonnet::domaindescription{$domain};
     } else {
@@ -1471,6 +1729,20 @@ Returns: value of designparamter $which
 ##############################################
 sub designparm {
     my ($which,$domain)=@_;
+    if ($ENV{'browser.blackwhite'} eq 'on') {
+	if ($which=~/\.(font|alink|vlink|link)$/) {
+	    return '#000000';
+	}
+	if ($which=~/\.(pgbg|sidebg)$/) {
+	    return '#FFFFFF';
+	}
+	if ($which=~/\.tabbg$/) {
+	    return '#CCCCCC';
+	}
+    }
+    if ($ENV{'environment.color.'.$which}) {
+	return $ENV{'environment.color.'.$which};
+    }
     $domain=&determinedomain($domain);
     if ($designhash{$domain.'.'.$which}) {
 	return $designhash{$domain.'.'.$which};
@@ -1495,6 +1767,8 @@ Inputs:
  $addentries, extra parameters for the <body> tag.
  $bodyonly, if defined, only return the <body> tag.
  $domain, if defined, force a given domain.
+ $forcereg, if page should register as content page (relevant for 
+            text interface only)
 
 Returns: A uniform header for LON-CAPA web pages.  
 If $bodyonly is nonzero, a string containing a <body> tag will be returned.
@@ -1508,7 +1782,7 @@ other decorations will be returned.
 
 ###############################################
 sub bodytag {
-    my ($title,$function,$addentries,$bodyonly,$domain)=@_;
+    my ($title,$function,$addentries,$bodyonly,$domain,$forcereg)=@_;
     unless ($function) {
 	$function='student';
         if ($ENV{'request.role'}=~/^(cc|in|ta|ep)/) {
@@ -1530,7 +1804,11 @@ sub bodytag {
     my $alink=&designparm($function.'.alink',$domain);
     my $vlink=&designparm($function.'.vlink',$domain);
     my $sidebg=&designparm($function.'.sidebg',$domain);
-
+# Accessibility font enhance
+    unless ($addentries) { $addentries=''; }
+    if ($ENV{'browser.fontenhance'} eq 'on') {
+	$addentries.=' style="font-size: x-large"';
+    }
  # role and realm
     my ($role,$realm)
        =&Apache::lonnet::plaintext((split(/\./,$ENV{'request.role'}))[0]);
@@ -1542,23 +1820,40 @@ sub bodytag {
     unless ($realm) { $realm='&nbsp;'; }
 # Set messages
     my $messages=&domainlogo($domain);
-# Output
+# Port for miniserver
+    my $lonhttpdPort=$Apache::lonnet::perlvar{'lonhttpdPort'};
+    if (!defined($lonhttpdPort)) { $lonhttpdPort='8080'; }
+# construct main body tag
     my $bodytag = <<END;
 <body bgcolor="$pgbg" text="$font" alink="$alink" vlink="$vlink" link="$link"
 $addentries>
 END
+    my $upperleft='<img src="http://'.$ENV{'HTTP_HOST'}.':'.
+                   $lonhttpdPort.$img.'" />';
     if ($bodyonly) {
         return $bodytag;
     } elsif ($ENV{'browser.interface'} eq 'textual') {
-        return $bodytag.'<h1>LON-CAPA: '.$title.
-         '</h1><a href="/adm/menu">Main Menu</a><hr />';
-    } else {
-        return(<<ENDBODY);
+# Accessibility
+        return $bodytag.&Apache::lonmenu::menubuttons($forcereg,'web',
+                                                      $forcereg).
+               '<h1>LON-CAPA: '.$title.'</h1>';
+    } elsif ($ENV{'environment.remote'} eq 'off') {
+# No Remote
+        return $bodytag.&Apache::lonmenu::menubuttons($forcereg,'web',
+                                                      $forcereg).
+               '<table bgcolor="'.$pgbg.'" width="100%" border="0" cellspacing="3" cellpadding="3"><tr><td bgcolor="'.$tabbg.'"><font size="+3" color="'.$font.'"><b>'.$title.
+'</b></font></td></tr></table>';
+    }
+
+#
+# Top frame rendering, Remote is up
+#
+    return(<<ENDBODY);
 $bodytag
 <table width="100%" cellspacing="0" border="0" cellpadding="0">
-<tr><td bgcolor="$font">
-<img src="http://$ENV{'HTTP_HOST'}:8080/$img" /></td>
-<td bgcolor="$font"><font color='$sidebg'>$messages</font></td>
+<tr><td bgcolor="$sidebg">
+$upperleft</td>
+<td bgcolor="$sidebg" align="right">$messages&nbsp;</td>
 </tr>
 <tr>
 <td rowspan="3" bgcolor="$tabbg">
@@ -1579,8 +1874,79 @@ $bodytag
 <td bgcolor="$tabbg" align="right"><font size="2">$realm</font>&nbsp;</td></tr>
 </table><br>
 ENDBODY
+}
+
+###############################################
+
+sub get_posted_cgi {
+    my $r=shift;
+
+    my $buffer;
+    
+    $r->read($buffer,$r->header_in('Content-length'),0);
+    unless ($buffer=~/^(\-+\w+)\s+Content\-Disposition\:\s*form\-data/si) {
+	my @pairs=split(/&/,$buffer);
+	my $pair;
+	foreach $pair (@pairs) {
+	    my ($name,$value) = split(/=/,$pair);
+	    $value =~ tr/+/ /;
+	    $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
+	    $name  =~ tr/+/ /;
+	    $name  =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
+	    &add_to_env("form.$name",$value);
+	}
+    } else {
+	my $contentsep=$1;
+	my @lines = split (/\n/,$buffer);
+	my $name='';
+	my $value='';
+	my $fname='';
+	my $fmime='';
+	my $i;
+	for ($i=0;$i<=$#lines;$i++) {
+	    if ($lines[$i]=~/^$contentsep/) {
+		if ($name) {
+		    chomp($value);
+		    if ($fname) {
+			$ENV{"form.$name.filename"}=$fname;
+			$ENV{"form.$name.mimetype"}=$fmime;
+		    } else {
+			$value=~s/\s+$//s;
+		    }
+		    &add_to_env("form.$name",$value);
+		}
+		if ($i<$#lines) {
+		    $i++;
+		    $lines[$i]=~
+		/Content\-Disposition\:\s*form\-data\;\s*name\=\"([^\"]+)\"/i;
+		    $name=$1;
+		    $value='';
+		    if ($lines[$i]=~/filename\=\"([^\"]+)\"/i) {
+			$fname=$1;
+			if 
+                            ($lines[$i+1]=~/Content\-Type\:\s*([\w\-\/]+)/i) {
+				$fmime=$1;
+				$i++;
+			    } else {
+				$fmime='';
+			    }
+		    } else {
+			$fname='';
+			$fmime='';
+		    }
+		    $i++;
+		}
+	    } else {
+		$value.=$lines[$i]."\n";
+	    }
+	}
     }
+    $ENV{'request.method'}=$ENV{'REQUEST_METHOD'};
+    $r->method_number(M_GET);
+    $r->method('GET');
+    $r->headers_in->unset('Content-length');
 }
+
 ###############################################
 
 sub get_unprocessed_cgi {
@@ -1883,6 +2249,37 @@ sub csv_samples_select_table {
     $i--;
     return($i);
 }
+
+=pod
+
+=item check_if_partid_hidden($id,$symb,$udom,$uname)
+
+Returns either 1 or undef
+
+1 if the part is to be hidden, undef if it is to be shown
+
+Arguments are:
+
+$id the id of the part to be checked
+$symb, optional the symb of the resource to check
+$udom, optional the domain of the user to check for
+$uname, optional the username of the user to check for
+
+=cut
+
+sub check_if_partid_hidden {
+    my ($id,$symb,$udom,$uname) = @_;
+    my $hiddenparts=&Apache::lonnet::EXT('resource.0.parameter_hiddenparts',
+					 $symb,$udom,$uname);
+    my @hiddenlist=split(/,/,$hiddenparts);
+    foreach my $checkid (@hiddenlist) {
+	if ($checkid =~ /^\s*\Q$id\E\s*$/) { return 1; }
+    }
+    return undef;
+}
+
+
+
 1;
 __END__;