--- loncom/homework/structuretags.pm	2000/08/22 16:19:26	1.4
+++ loncom/homework/structuretags.pm	2000/10/05 19:26:16	1.8
@@ -1,6 +1,4 @@
-# The LearningOnline Network with CAPA
-# <script> definiton
-
+# The LearningOnline Network with CAPA # <script> definiton
 
 package Apache::structuretags; 
 
@@ -8,7 +6,7 @@ use strict;
 use Apache::lonnet;
 
 sub BEGIN {
-  &Apache::lonxml::register('Apache::structuretags',('block','while'));
+  &Apache::lonxml::register('Apache::structuretags',('block','while','randomlist'));
 }
 
 sub start_block {
@@ -37,25 +35,83 @@ sub start_while {
   $code =~ s/\"//g;
   $code .=';return $condition;';
 
-  print "<H2>WHILE CONDITION = [$code]</H2>";
+  push( @Apache::structuretags::whileconds, $code); 
   my $result = &Apache::run::run($code,$safeeval);
   my $bodytext=$$parser[$#$parser]->get_text("/while");
-  if ( $result ) { # condition is TRUE, bodytext is evaluated
-# push the bodytext into parser stack
-     my $tempparser=HTML::TokeParser->new(\$bodytext);
-     push (@$parser,$tempparser);
-  } else { # condition is FALSE initially, skip bodytext
+  push( @Apache::structuretags::whilebody, $bodytext);
+  if ( $result ) { 
+    &Apache::lonxml::newparser($parser,\$bodytext);
   }
   return "";
 }
 
 sub end_while {
-# pop parser from parser stack
-# check if condition is TRUE, 
-#   TRUE  then push content into parser stack
-#   FALSE then continue
+  my ($target,$token,$parstack,$parser,$safeeval)=@_;
+  my $code = pop @Apache::structuretags::whileconds;
+  my $bodytext = pop @Apache::structuretags::whilebody;
+  my $result = &Apache::run::run($code,$safeeval);
+  if ( $result ) { 
+    &Apache::lonxml::newparser($parser,\$bodytext);
+  } 
+  return "";
+}
 
+# <randomlist> 
+#  <tag1>..</tag1>
+#  <tag2>..</tag2>
+#  <tag3>..</tag3>
+#  ... 
+# </randomlist>
+sub start_randomlist {
+  my ($target,$token,$parstack,$parser,$safeeval)=@_;
+  my $body= &Apache::lonxml::get_all_text("randomlist",$$parser[$#$parser]);
+  my $b_parser= HTML::TokeParser->new(\$body);
+  my $b_tok;
+  my @randomlist;
+  my $list_item;
+
+  while($b_tok = $b_parser->get_token() ) {
+    if($b_tok->[0] eq 'S') { # start tag
+    # get content of the tag until matching end tag
+    # get all text upto the matching tag
+    # and push the content into @randomlist
+      $list_item = &Apache::lonxml::get_all_text($b_tok->[1],$b_parser);
+      $list_item = "$b_tok->[4]"."$list_item"."</$b_tok->[1]>";
+      push(@randomlist,$list_item);
+   #  print "<BR><B>START-TAG $b_tok->[1], $b_tok->[4], $list_item</B>";
+    }
+    if($b_tok->[0] eq 'T') { # text
+    # what to do with text in between tags?
+      #  print "<B>TEXT $b_tok->[1]</B><BR>";
+    }
+    # if($b_tok->[0] eq 'E') { # end tag, should not happen
+      #  print "<B>END-TAG $b_tok->[1]</B><BR>";
+    # }
+  }
+  my @idx_arr = (0 .. $#randomlist);
+  &Apache::structuretags::shuffle(\@idx_arr);
+  my $bodytext = '';
+  for(0 .. $#randomlist) {
+    $bodytext .= "$randomlist[ $idx_arr[$_] ]";
+  }
+
+  &Apache::lonxml::newparser($parser,\$bodytext);
+  return "";
+}
+
+sub shuffle {
+    my $a=shift;
+    my $i;
+    for($i=@$a;--$i;) {
+      my $j=int rand($i+1);
+      next if $i == $j;
+      @$a[$i,$j] = @$a[$j,$i];
+    }
 }
 
+sub end_randomlist {
+}
+
+
 1;
 __END__