--- loncom/xml/lonxml.pm	2004/02/19 19:29:40	1.302
+++ loncom/xml/lonxml.pm	2005/01/30 12:56:45	1.354
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # XML Parser Module 
 #
-# $Id: lonxml.pm,v 1.302 2004/02/19 19:29:40 sakharuk Exp $
+# $Id: lonxml.pm,v 1.354 2005/01/30 12:56:45 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -36,30 +36,11 @@
 # The C source of the Code may not be distributed by the Licensee
 # to any other parties under any circumstances.
 #
-# last modified 06/26/00 by Alexander Sakharuk
-# 11/6 Gerd Kortemeyer
-# 6/1/1 Gerd Kortemeyer
-# 2/21,3/13 Guy
-# 3/29,5/4 Gerd Kortemeyer
-# 5/26 Gerd Kortemeyer
-# 5/27 H. K. Ng
-# 6/2,6/3,6/8,6/9 Gerd Kortemeyer
-# 6/12,6/13 H. K. Ng
-# 6/16 Gerd Kortemeyer
-# 7/27 H. K. Ng
-# 8/7,8/9,8/10,8/11,8/15,8/16,8/17,8/18,8/20,8/23,8/24 Gerd Kortemeyer
-# Guy Albertelli
-# 9/26 Gerd Kortemeyer
-# Dec Guy Albertelli
-# YEAR=2002
-# 1/1 Gerd Kortemeyer
-# 1/2 Matthew Hall
-# 1/3 Gerd Kortemeyer
-#
+
 
 package Apache::lonxml; 
 use vars 
-qw(@pwd @outputstack $redirection $import @extlinks $metamode $evaluate %insertlist @namespace $prevent_entity_encode $errorcount $warningcount);
+qw(@pwd @outputstack $redirection $import @extlinks $metamode $evaluate %insertlist @namespace $errorcount $warningcount @htmlareafields);
 use strict;
 use HTML::LCParser();
 use HTML::TreeBuilder();
@@ -70,7 +51,7 @@ use Math::Cephes();
 use Math::Random();
 use Opcode();
 use POSIX qw(strftime);
-
+use Time::HiRes qw( gettimeofday tv_interval );
 
 sub register {
   my ($space,@taglist) = @_;
@@ -141,9 +122,6 @@ $evaluate = 1;
 # stores the list of active tag namespaces
 @namespace=();
 
-# if 0 all high ASCII characters will be encoded into HTML Entities
-$prevent_entity_encode=0;
-
 # has the dynamic menu been updated to know about this resource
 $Apache::lonxml::registered=0;
 
@@ -172,6 +150,7 @@ $Apache::lonxml::warnings_error_header='
 
 sub xmlbegin {
   my $output='';
+  @htmlareafields=();
   if ($ENV{'browser.mathml'}) {
       $output='<?xml version="1.0"?>'
             .'<?xml-stylesheet type="text/css" href="/adm/MathML/mathml.css"?>'
@@ -180,19 +159,28 @@ sub xmlbegin {
             .'<html xmlns:math="http://www.w3.org/1998/Math/MathML" ' 
 		.'xmlns="http://www.w3.org/TR/REC-html40">';
   } else {
-      $output='<html>';
+      $output='<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html>';
   }
   return $output;
 }
 
 sub xmlend {
+    my ($target,$parser)=@_;
     my $mode='xml';
     my $status='OPEN';
     if ($Apache::lonhomework::parsing_a_problem) {
 	$mode='problem';
 	$status=$Apache::inputtags::status[-1]; 
     }
-    return &Apache::lonfeedback::list_discussion($mode,$status).'</html>';
+    my $discussion=&Apache::lonfeedback::list_discussion($mode,$status);    
+    if ($target eq 'tex') {
+	$discussion.='<tex>\keephidden{ENDOFPROBLEM}\vskip 0.5mm\noindent\makebox[\textwidth/$number_of_columns][b]{\hrulefill}\end{document}</tex>';
+	&Apache::lonxml::newparser($parser,\$discussion,'');
+	return '';
+    } else {
+	return $discussion.'</html>';
+    }
 }
 
 sub tokeninputfield {
@@ -300,7 +288,7 @@ sub fontsettings() {
     my $headerstring='';
     if (($ENV{'browser.os'} eq 'mac') && (!$ENV{'browser.mathml'})) { 
 	$headerstring.=
-	    '<meta Content-Type="text/html; charset=x-mac-roman">';
+	    '<meta Content-Type="text/html; charset=x-mac-roman" />';
     } elsif (!$ENV{'browser.mathml'} && $ENV{'browser.unicode'}) {
 	$headerstring.=
 	    '<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />';
@@ -333,13 +321,15 @@ sub xmlparse {
      my $bodytext=
 	 $ENV{'course.'.$ENV{'request.course.id'}.'.default_xml_style'};
      if ($bodytext) {
-       my $location=&Apache::lonnet::filelocation('',$bodytext);
-       my $styletext=&Apache::lonnet::getfile($location);
-       if ($styletext ne '-1') {
-          %style_for_target = (%style_for_target,
-                          &Apache::style::styleparser($target,$styletext));
-       }
-    }
+	 foreach my $file (split(',',$bodytext)) {
+	     my $location=&Apache::lonnet::filelocation('',$file);
+	     my $styletext=&Apache::lonnet::getfile($location);
+	     if ($styletext ne '-1') {
+		 %style_for_target = (%style_for_target,
+				      &Apache::style::styleparser($target,$styletext));
+	     }
+	 }
+     }
  } elsif ($ENV{'construct.style'} && ($ENV{'request.state'} eq 'construct')) {
      my $location=&Apache::lonnet::filelocation('',$ENV{'construct.style'});
      my $styletext=&Apache::lonnet::getfile($location);
@@ -378,46 +368,56 @@ sub xmlparse {
 
 sub htmlclean {
     my ($raw,$full)=@_;
+# Take care of CRLF etc
 
-    my $tree = HTML::TreeBuilder->new;
-    $tree->ignore_unknown(0);
-
-    $tree->parse($raw);
-
-    my $output= $tree->as_HTML(undef,' ');
-
-    $output=~s/\<(br|hr|img|meta|allow)(.*?)\>/\<$1$2 \/\>/gis;
-    $output=~s/\<\/(br|hr|img|meta|allow)\>//gis;
+    $raw=~s/\r\f/\n/gs; $raw=~s/\f\r/\n/gs;
+    $raw=~s/\r\n/\n/gs; $raw=~s/\n\r/\n/gs;
+    $raw=~s/\f/\n/gs; $raw=~s/\r/\n/gs;
+    $raw=~s/\&\#10\;/\n/gs; $raw=~s/\&\#13\;/\n/gs;
+
+# Generate empty tags, remove wrong end tags
+    $raw=~s/\<(br|hr|img|meta|allow|basefont)([^\>\/]*?)\>/\<$1$2 \/\>/gis;
+    $raw=~s/\<\/(br|hr|img|meta|allow|basefont)\>//gis;
     unless ($full) {
-       $output=~s/\<[\/]*(body|head|html)\>//gis;
+       $raw=~s/\<[\/]*(body|head|html)\>//gis;
     }
-
-    $tree = $tree->delete;
-
-    return $output;
+# Make standard tags lowercase
+    foreach ('html','body','head','meta','h1','h2','h3','h4','b','i','m',
+             'table','tr','td','th','p','br','hr','img','embed','font',
+             'a','strong','center','title','basefont') {
+	$raw=~s/\<$_\s*\>/\<$_\>/gis;
+        $raw=~s/\<\/$_\s*\>/<\/$_\>/gis;
+        $raw=~s/\<$_\s([^\>]*)\>/<$_ $1\>/gis;
+    }
+    return $raw;
 }
 
 sub latex_special_symbols {
     my ($string,$where)=@_;
     if ($where eq 'header') {
 	$string =~ s/(\\|_|\^)/ /g;
-	$string =~ s/(\$|%|\#|&|\{|\})/\\$1/g;
+	$string =~ s/(\$|%|\{|\})/\\$1/g;
 	$string =~ s/_/ /g;
+	$string=&Apache::lonprintout::character_chart($string);
+	# any & or # leftover should be safe to just escape
+        $string=~s/([^\\])\&/$1\\\&/g;
+        $string=~s/([^\\])\#/$1\\\#/g;
     } else {
-	$string=~s/\\ /\\char92 /g;
-	$string=~s/\^/\\\^\\strut /g;
-	$string=~s/\~/\\char126 /g;
-	#fixup & if it doesn't look like
-        # &#123; or &alpha;
-	$string=~s/(&(?!((\#[0-9]+)|([a-z]+));))/\\$1/gi;
-        $string=~s/([^&\\])\#/$1\\#/g;
-	$string=~s/\#\#/\#\\#/g;
-	$string=~s/(\$|_|{|})/\\$1/g;
-	$string=~s/\\char92 /\\texttt{\\char92}/g;
-	$string=~s/(>|<)/\$$1\$/g; #more or less
-	if ($string=~m/\d%/) {$string =~ s/(\d)%/$1\\%/g;} #percent after digit
-	if ($string=~m/\s%/) {$string =~ s/(\s)%/$1\\%/g;} #percent after space
-	if ($string eq '%.') {$string = '\%.';} #percent at the end of statement
+	$string=~s/\\/\\ensuremath{\\backslash}/g;
+	$string=~s/([^\\]|^)\%/$1\\\%/g;
+	$string=~s/([^\\]|^)\$/$1\\\$/g;
+	$string=~s/([^\\])\_/$1\\_/g;
+	$string=~s/\$\$/\$\\\$/g;
+	$string=~s/\_\_/\_\\\_/g;
+	$string=~s/\#\#/\#\\\#/g;
+        $string=~s/([^\\]|^)(\~|\^)/$1\\$2\\strut /g;
+	$string=~s/(>|<)/\\ensuremath\{$1\}/g; #more or less
+	$string=&Apache::lonprintout::character_chart($string);
+	# any & or # leftover should be safe to just escape
+        $string=~s/([^\\]|^)\&/$1\\\&/g;
+        $string=~s/([^\\]|^)\#/$1\\\#/g;
+        $string=~s/\|/\$\\mid\$/g;
+#single { or } How to escape?
     }
     return $string;
 }
@@ -480,7 +480,7 @@ sub inner_xmlparse {
 	    #clear out any tags that didn't end
 	    while ($token->[1] ne $$stack['-1'] && ($#$stack > -1)) {
 		my $lasttag=$$stack[-1];
-		if ($token->[1] =~ /^$lasttag$/i) {
+		if ($token->[1] =~ /^\Q$lasttag\E$/i) {
 		    &Apache::lonxml::warning('Using tag &lt;/'.$token->[1].'&gt; on line '.$token->[3].' as end tag to &lt;'.$$stack[-1].'&gt;');
 		    last;
 		} else {
@@ -515,10 +515,6 @@ sub inner_xmlparse {
 	  }
       }
 
-      # Encode any high ASCII characters
-#      if (!$Apache::lonxml::prevent_entity_encode) {
-#	$result=&HTML::Entities::encode($result,"\200-\377");
-#      }
       if ($Apache::lonxml::redirection) {
 	$Apache::lonxml::outputstack['-1'] .= $result;
       } else {
@@ -548,6 +544,10 @@ sub inner_xmlparse {
   return $finaloutput;
 }
 
+## 
+## Looks to see if there is a subroutine defined for this tag.  If so, call it,
+## otherwise do not call it as we do not know what it is.
+##
 sub callsub {
   my ($sub,$target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
   my $currentstring='';
@@ -580,6 +580,10 @@ sub callsub {
 					     $parstack,$parser,$safeeval,
 					     $style);
       } else {
+          if ($target eq 'tex') {
+              # throw away tag name
+              return '';
+          }
 	#&Apache::lonxml::debug("NOT Calling sub $sub in $space $metamode");
 	if ($metamode <1) {
 	  if (defined($token->[4]) && ($metamode < 1)) {
@@ -620,6 +624,7 @@ sub setup_globals {
   my ($request,$target)=@_;
   $Apache::lonxml::request=$request;
   $Apache::lonxml::registered = 0;
+  @Apache::lonxml::htmlareafields=();
   $errorcount=0;
   $warningcount=0;
   $Apache::lonxml::default_homework_loaded=0;
@@ -678,7 +683,9 @@ sub init_safespace {
   $safehole->wrap(\&Apache::scripttag::xmlparse,$safeeval,'&xmlparse');
   $safehole->wrap(\&Apache::outputtags::multipart,$safeeval,'&multipart');
   $safehole->wrap(\&Apache::lonnet::EXT,$safeeval,'&EXT');
-  
+  $safehole->wrap(\&Apache::chemresponse::chem_standard_order,$safeeval,
+		  '&chem_standard_order');
+
   $safehole->wrap(\&Math::Cephes::asin,$safeeval,'&asin');
   $safehole->wrap(\&Math::Cephes::acos,$safeeval,'&acos');
   $safehole->wrap(\&Math::Cephes::atan,$safeeval,'&atan');
@@ -750,16 +757,21 @@ sub init_safespace {
   $safehole->wrap(\&Math::Random::random_set_seed_from_phrase,$safeeval,'&random_set_seed_from_phrase');
   $safehole->wrap(\&Math::Random::random_get_seed,$safeeval,'&random_get_seed');
   $safehole->wrap(\&Math::Random::random_set_seed,$safeeval,'&random_set_seed');
+  $safehole->wrap(\&Apache::lonxml::error,$safeeval,'&LONCAPA_INTERNAL_ERROR');
+  $safehole->wrap(\&Apache::lonxml::debug,$safeeval,'&LONCAPA_INTERNAL_DEBUG');
+  $safehole->wrap(\&Apache::caparesponse::get_sigrange,$safeeval,'&LONCAPA_INTERNAL_get_sigrange');
 
 #need to inspect this class of ops
 # $safeeval->deny(":base_orig");
+  $safeeval->permit("require");
   $safeinit .= ';$external::target="'.$target.'";';
   my $rndseed;
   my ($symb,$courseid,$domain,$name) = &Apache::lonxml::whichuser();
   $rndseed=&Apache::lonnet::rndseed($symb,$courseid,$domain,$name);
-  $safeinit .= ';$external::randomseed='.$rndseed.';';
+  $safeinit .= ';$external::randomseed="'.$rndseed.'";';
   &Apache::lonxml::debug("Setting rndseed to $rndseed");
   &Apache::run::run($safeinit,$safeeval);
+
 }
 
 sub default_homework_load {
@@ -774,18 +786,26 @@ sub default_homework_load {
     }
 }
 
+my $metamode_was;
 sub startredirection {
-  $Apache::lonxml::redirection++;
-  push (@Apache::lonxml::outputstack, '');
+    if (!$Apache::lonxml::redirection) {
+	$metamode_was=$Apache::lonxml::metamode;
+    }
+    $Apache::lonxml::metamode=0;
+    $Apache::lonxml::redirection++;
+    push (@Apache::lonxml::outputstack, '');
 }
 
 sub endredirection {
-  if (!$Apache::lonxml::redirection) {
-    &Apache::lonxml::error("Endredirection was called, before a startredirection, perhaps you have unbalanced tags. Some debuging information:".join ":",caller);
-    return '';
-  }
-  $Apache::lonxml::redirection--;
-  pop @Apache::lonxml::outputstack;
+    if (!$Apache::lonxml::redirection) {
+	&Apache::lonxml::error("Endredirection was called, before a startredirection, perhaps you have unbalanced tags. Some debuging information:".join ":",caller);
+	return '';
+    }
+    $Apache::lonxml::redirection--;
+    if (!$Apache::lonxml::redirection) {
+	$Apache::lonxml::metamode=$metamode_was;
+    }
+    pop @Apache::lonxml::outputstack;
 }
 
 sub end_tag {
@@ -801,6 +821,8 @@ sub initdepth {
   $Apache::lonxml::olddepth=-1;
 }
 
+my @timers;
+my $lasttime;
 sub increasedepth {
   my ($token) = @_;
   $Apache::lonxml::depth++;
@@ -808,8 +830,15 @@ sub increasedepth {
   if ($Apache::lonxml::depthcounter[$Apache::lonxml::depth]==1) {
     $Apache::lonxml::olddepth=$Apache::lonxml::depth;
   }
+  my $time;
+  if ($Apache::lonxml::debug eq "1") {
+      push(@timers,[&gettimeofday()]);
+      $time=&tv_interval($lasttime);
+      $lasttime=[&gettimeofday()];
+  }
+  my $spacing='  'x($Apache::lonxml::depth-1);
   my $curdepth=join('_',@Apache::lonxml::depthcounter);
-  &Apache::lonxml::debug("s $Apache::lonxml::depth : $Apache::lonxml::olddepth : $curdepth : $token->[1]\n");
+  &Apache::lonxml::debug("s$spacing$Apache::lonxml::depth : $Apache::lonxml::olddepth : $curdepth : $token->[1] : $time : \n");
 #print "<br />s $Apache::lonxml::depth : $Apache::lonxml::olddepth : $curdepth : $token->[1]\n";
 }
 
@@ -824,37 +853,44 @@ sub decreasedepth {
     &Apache::lonxml::warning(&mt("Missing tags, unable to properly run file."));
     $Apache::lonxml::depth='-1';
   }
+  my ($timer,$time);
+  if ($Apache::lonxml::debug eq "1") {
+      $timer=pop(@timers);
+      $time=&tv_interval($lasttime);
+      $lasttime=[&gettimeofday()];
+  }
+  my $spacing='  'x$Apache::lonxml::depth;
   my $curdepth=join('_',@Apache::lonxml::depthcounter);
-  &Apache::lonxml::debug("e $Apache::lonxml::depth : $Apache::lonxml::olddepth : $token->[1] : $curdepth\n");
+  &Apache::lonxml::debug("e$spacing$Apache::lonxml::depth : $Apache::lonxml::olddepth : $curdepth : $token->[1] : $time : ".&tv_interval($timer)."\n");
 #print "<br />e $Apache::lonxml::depth : $Apache::lonxml::olddepth : $token->[1] : $curdepth\n";
 }
 
 sub get_all_text_unbalanced {
 #there is a copy of this in lonpublisher.pm
- my($tag,$pars)= @_;
- my $token;
- my $result='';
- $tag='<'.$tag.'>';
- while ($token = $$pars[-1]->get_token) {
-   if (($token->[0] eq 'T')||($token->[0] eq 'C')||($token->[0] eq 'D')) {
-     $result.=$token->[1];
-   } elsif ($token->[0] eq 'PI') {
-     $result.=$token->[2];
-   } elsif ($token->[0] eq 'S') {
-     $result.=$token->[4];
-   } elsif ($token->[0] eq 'E')  {
-     $result.=$token->[2];
-   }
-   if ($result =~ /(.*)\Q$tag\E(.*)/s) {
-     &Apache::lonxml::debug('Got a winner with leftovers ::'.$2);
-     &Apache::lonxml::debug('Result is :'.$1);
-     $result=$1;
-     my $redo=$tag.$2;
-     &Apache::lonxml::newparser($pars,\$redo);
-     last;
-   }
- }
- return $result
+    my($tag,$pars)= @_;
+    my $token;
+    my $result='';
+    $tag='<'.$tag.'>';
+    while ($token = $$pars[-1]->get_token) {
+	if (($token->[0] eq 'T')||($token->[0] eq 'C')||($token->[0] eq 'D')) {
+	    $result.=$token->[1];
+	} elsif ($token->[0] eq 'PI') {
+	    $result.=$token->[2];
+	} elsif ($token->[0] eq 'S') {
+	    $result.=$token->[4];
+	} elsif ($token->[0] eq 'E')  {
+	    $result.=$token->[2];
+	}
+	if ($result =~ /\Q$tag\E/is) {
+	    ($result,my $redo)=$result =~ /(.*)\Q$tag\E(.*)/is;
+	    #&Apache::lonxml::debug('Got a winner with leftovers ::'.$2);
+	    #&Apache::lonxml::debug('Result is :'.$1);
+	    $redo=$tag.$redo;
+	    &Apache::lonxml::newparser($pars,\$redo);
+	    last;
+	}
+    }
+    return $result
 }
 
 sub increment_counter {
@@ -907,12 +943,12 @@ sub get_all_text {
 		} elsif ($token->[0] eq 'PI') {
 		    $result.=$token->[2];
 		} elsif ($token->[0] eq 'S') {
-		    if ($token->[1] =~ /^$tag$/i) { $depth++; }
-		    if ($token->[1] =~ /^LONCAPA_INTERNAL_TURN_STYLE_ON$/i) { $Apache::lonxml::usestyle=1; }
-		    if ($token->[1] =~ /^LONCAPA_INTERNAL_TURN_STYLE_OFF$/i) { $Apache::lonxml::usestyle=0; }
+		    if ($token->[1] =~ /^\Q$tag\E$/i) { $depth++; }
+		    if ($token->[1] =~ /^LONCAPA_INTERNAL_TURN_STYLE_ON$/) { $Apache::lonxml::usestyle=1; }
+		    if ($token->[1] =~ /^LONCAPA_INTERNAL_TURN_STYLE_OFF$/) { $Apache::lonxml::usestyle=0; }
 		    $result.=$token->[4];
 		} elsif ($token->[0] eq 'E')  {
-		    if ( $token->[1] =~ /^$tag$/i) { $depth--; }
+		    if ( $token->[1] =~ /^\Q$tag\E$/i) { $depth--; }
 		    #skip sending back the last end tag
 		    if ($depth == 0 && exists($$style{'/'.$token->[1]}) && $Apache::lonxml::usestyle) {
 			my $string=
@@ -941,7 +977,7 @@ sub get_all_text {
 	    #never found the end tag ran out of text, throw error send back blank
 	    &error('Never found end tag for &lt;'.$tag.
 		   '&gt; current string <pre>'.
-		   &HTML::Entities::encode($result).
+		   &HTML::Entities::encode($result,'<>&"').
 		   '</pre>');
 	    if ($gotfullstack) {
 		my $newstring='</'.$tag.'>'.$result;
@@ -959,13 +995,13 @@ sub get_all_text {
 		} elsif ($token->[0] eq 'PI') {
 		    $result.=$token->[2];
 		} elsif ($token->[0] eq 'S') {
-		    if ( $token->[1] =~ /^$tag$/i) {
+		    if ( $token->[1] =~ /^\Q$tag\E$/i) {
 			$$pars[-1]->unget_token($token); last;
 		    } else {
 			$result.=$token->[4];
 		    }
-		    if ($token->[1] =~ /^LONCAPA_INTERNAL_TURN_STYLE_ON$/i) { $Apache::lonxml::usestyle=1; }
-		    if ($token->[1] =~ /^LONCAPA_INTERNAL_TURN_STYLE_OFF$/i) { $Apache::lonxml::usestyle=0; }
+		    if ($token->[1] =~ /^LONCAPA_INTERNAL_TURN_STYLE_ON$/) { $Apache::lonxml::usestyle=1; }
+		    if ($token->[1] =~ /^LONCAPA_INTERNAL_TURN_STYLE_OFF$/) { $Apache::lonxml::usestyle=0; }
 		} elsif ($token->[0] eq 'E')  {
 		    $result.=$token->[2];
 		}
@@ -998,6 +1034,8 @@ sub parstring {
     unless ($_=~/\W/) {
       my $val=$token->[2]->{$_};
       $val =~ s/([\%\@\\\"\'])/\\$1/g;
+      $val =~ s/(\$[^{a-zA-Z_])/\\$1/g;
+      $val =~ s/(\$)$/\\$1/;
       #if ($val =~ m/^[\%\@]/) { $val="\\".$val; }
       $temp .= "my \$$_=\"$val\";";
     }
@@ -1047,7 +1085,7 @@ sub afterburn {
            my $anchorname=$_;
 	   my $matchthis=$anchorname;
            $matchthis=~s/\_+/\\s\+/g;
-           $result=~s/($matchthis)/\<font color=\"red\"\>$1\<\/font\>/gs;
+           $result=~s/(\Q$matchthis\E)/\<font color=\"red\"\>$1\<\/font\>/gs;
        }
     }
     if ($ENV{'form.link'}) {
@@ -1055,14 +1093,14 @@ sub afterburn {
            my ($anchorname,$linkurl)=split(/\>/,$_);
 	   my $matchthis=$anchorname;
            $matchthis=~s/\_+/\\s\+/g;
-           $result=~s/($matchthis)/\<a href=\"$linkurl\"\>$1\<\/a\>/gs;
+           $result=~s/(\Q$matchthis\E)/\<a href=\"$linkurl\"\>$1\<\/a\>/gs;
        }
     }
     if ($ENV{'form.anchor'}) {
         my $anchorname=$ENV{'form.anchor'};
 	my $matchthis=$anchorname;
         $matchthis=~s/\_+/\\s\+/g;
-        $result=~s/($matchthis)/\<a name=\"$anchorname\"\>$1\<\/a\>/s;
+        $result=~s/(\Q$matchthis\E)/\<a name=\"$anchorname\"\>$1\<\/a\>/s;
         $result.=(<<"ENDSCRIPT");
 <script type="text/javascript">
     document.location.hash='$anchorname';
@@ -1086,21 +1124,20 @@ sub storefile {
 }
 
 sub createnewhtml {
-  my $filecontents=(<<SIMPLECONTENT);
+    my $title=&mt('Title of document goes here');
+    my $body=&mt('Body of document goes here');
+    my $filecontents=(<<SIMPLECONTENT);
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml/11/DTD/xhtml11.dtd">
 <html>
 <head>
-<title>
-                           Title of Document Goes Here
-</title>
+<title>$title</title>
 </head>
 <body bgcolor="#FFFFFF">
-
-                           Body of Document Goes Here
-
+$body
 </body>
 </html>
 SIMPLECONTENT
-  return $filecontents;
+    return $filecontents;
 }
 
 sub createnewsty {
@@ -1118,11 +1155,40 @@ SIMPLECONTENT
 
 sub inserteditinfo {
       my ($result,$filecontents,$filetype)=@_;
-      $filecontents = &HTML::Entities::encode($filecontents);
+      $filecontents = &HTML::Entities::encode($filecontents,'<>&"');
 #      my $editheader='<a href="#editsection">Edit below</a><hr />';
       my $xml_help = '';
+      my $initialize='';
       if ($filetype eq 'html') {
-	  $xml_help=Apache::loncommon::helpLatexCheatsheet();
+	  my $addbuttons=&Apache::lonhtmlcommon::htmlareaaddbuttons();
+	  $initialize=&Apache::lonhtmlcommon::htmlareaheaders().
+	      &Apache::lonhtmlcommon::spellheader();
+	  if (!&Apache::lonhtmlcommon::htmlareablocked() &&
+	      &Apache::lonhtmlcommon::htmlareabrowser()) {
+	      $initialize.=(<<FULLPAGE);
+<script type="text/javascript">
+$addbuttons
+
+    HTMLArea.loadPlugin("FullPage");
+
+    function initDocument() {
+	var editor=new HTMLArea("filecont",config);
+	editor.registerPlugin(FullPage);
+	editor.generate();
+    }
+</script>
+FULLPAGE
+          } else {
+	      $initialize.=(<<FULLPAGE);
+<script type="text/javascript">
+$addbuttons
+    function initDocument() {
+    }
+</script>
+FULLPAGE
+	  }
+          $result=~s/\<body([^\>]*)\>/\<body onload="initDocument()" $1\>/i;
+	  $xml_help=&Apache::loncommon::helpLatexCheatsheet();
       }
       my $cleanbut = '';
       if ($filetype eq 'html') {
@@ -1135,21 +1201,25 @@ sub inserteditinfo {
 					 'ed' => 'Edit');
       my $buttons=(<<BUTTONS);
 $cleanbut
-<input type="submit" name="savethisfile" value="$lt{'st'}" />
-<input type="submit" name="viewmode" value="$lt{'vi'}" />
+<input type="submit" name="savethisfile" accesskey="s"  value="$lt{'st'}" />
+<input type="submit" name="viewmode" accesskey="v" value="$lt{'vi'}" />
 BUTTONS
+      $buttons.=&Apache::lonhtmlcommon::spelllink('xmledit','filecont');
+      $buttons.=&Apache::lonhtmlcommon::htmlareaselectactive('filecont');
       my $editfooter=(<<ENDFOOTER);
+$initialize
 <hr />
 <a name="editsection" />
-<form method="post">
+<form method="post" name="xmledit">
 $xml_help
 <input type="hidden" name="editmode" value="$lt{'ed'}" />
 $buttons<br />
-<textarea cols="80" rows="40" name="filecont">$filecontents</textarea>
+<textarea cols="80" rows="44" name="filecont" id="filecont">$filecontents</textarea>
 <br />$buttons
 <br />
 </form>
 $titledisplay
+</body>
 ENDFOOTER
 #      $result=~s/(\<body[^\>]*\>)/$1$editheader/is;
       $result=~s/(\<\/body\>)/$editfooter/is;
@@ -1196,6 +1266,8 @@ sub handler {
 	&Apache::loncommon::content_type($request,'text/html');
     }
     &Apache::loncommon::no_cache($request);
+    $request->set_last_modified(&Apache::lonnet::metadata($request->uri,
+							  'lastrevisiondate'));
     $request->send_http_header;
     
     return OK if $request->header_only;
@@ -1214,8 +1286,10 @@ sub handler {
     unless ($ENV{'request.state'} eq 'published') {
 	if (($ENV{'form.savethisfile'}) || ($ENV{'form.attemptclean'})) {
 	    if (&storefile($file,$ENV{'form.filecont'})) {
-		$request->print("<font COLOR=\"#0000FF\">".&mt('Updated').": ".
-&Apache::lonlocal::locallocaltime(time)." </font>");
+		&Apache::lonxml::info("<font COLOR=\"#0000FF\">".
+				      &mt('Updated').": ".
+				      &Apache::lonlocal::locallocaltime(time).
+				      " </font>");
 	    } 
 	}
     }
@@ -1235,7 +1309,7 @@ $bodytag
 </body>
 </html>
 ENDNOTFOUND
-    $filecontents='';
+        $filecontents='';
 	if ($ENV{'request.state'} ne 'published') {
 	    if ($filetype eq 'sty') {
 		$filecontents=&createnewsty();
@@ -1246,6 +1320,10 @@ ENDNOTFOUND
 	}
     } else {
 	unless ($ENV{'request.state'} eq 'published') {
+	    if ($filecontents=~/BEGIN LON-CAPA Internal/) {
+		&Apache::lonxml::error(&mt('This file appears to be a rendering of a Lon-CAPA resource. If this is correct, this resource will act very oddly and incorrectly.'));
+	    }
+
 	    if ($ENV{'form.attemptclean'}) {
 		$filecontents=&htmlclean($filecontents,1);
 	    }
@@ -1267,7 +1345,13 @@ ENDNOTFOUND
 	if ($ENV{'form.editmode'} && (!($ENV{'form.viewmode'}))) {
 	    my $displayfile=$request->uri;
 	    $displayfile=~s/^\/[^\/]*//;
-	    $result='<html><body bgcolor="#FFFFFF"><h3>'.$displayfile.
+	    my $bodytag='<body bgcolor="#FFFFFF">';
+	    if ($ENV{'environment.remote'} eq 'off') {
+		$bodytag=&Apache::loncommon::bodytag();
+	    }
+	    $result='<html>'.$bodytag.
+		&Apache::lonxml::message_location().'<h3>'.
+		$displayfile.
 		'</h3></body></html>';
 	    $result=&inserteditinfo($result,$filecontents,$filetype);
 	}
@@ -1275,7 +1359,7 @@ ENDNOTFOUND
     if ($filetype eq 'html') { writeallows($request->uri); }
 	
     
-
+    &Apache::lonxml::add_messages(\$result);
     $request->print($result);
     
     return OK;
@@ -1299,54 +1383,100 @@ sub debug {
 	$|=1;
 	my $request=$Apache::lonxml::request;
 	if (!$request) { $request=Apache->request; }
-	$request->print('<font size="-2"><pre>DEBUG:'.&HTML::Entities::encode($_[0])."</pre></font>\n");
+	$request->print('<font size="-2"><pre>DEBUG:'.&HTML::Entities::encode($_[0],'<>&"')."</pre></font>\n");
+	#&Apache::lonnet::logthis($_[0]);
     }
 }
 
-sub error {
-  $errorcount++;
-  my $request=$Apache::lonxml::request;
-  if (!$request) { $request=Apache->request; }
-  if (($Apache::lonxml::debug eq 1) || ($ENV{'request.state'} eq 'construct') ) {
-    # If printing in construction space, put the error inside <pre></pre>
-      $request->print($Apache::lonxml::warnings_error_header.
-		      "<b>ERROR:</b>".join("\n",@_)."\n");
-      $Apache::lonxml::warnings_error_header='';
-  } else {
-    $request->print("<b>An Error occured while processing this resource. The instructor has been notified.</b> <br />");
-    #notify author
-    &Apache::lonmsg::author_res_msg($ENV{'request.filename'},join('<br />',@_));
-    #notify course
-    if ( $ENV{'request.course.id'} ) {
-      my (undef,%users)=&Apache::lonfeedback::decide_receiver(undef,0,1,1,1);
-      my $declutter=&Apache::lonnet::declutter($ENV{'request.filename'});
-      foreach (keys %users) {
-	my ($user,$domain) = split(/:/, $_);
-	&Apache::lonmsg::user_normal_msg($user,$domain,
-        "Error [$declutter]",join('<br />',@_));
-      }
+sub show_error_warn_msg {
+    if ($ENV{'request.filename'} eq '/home/httpd/html/res/lib/templates/simpleproblem.problem' &&
+	&Apache::lonnet::allowed('mdc',$ENV{'request.course.id'})) {
+	return 1;
     }
+    return (($Apache::lonxml::debug eq 1) ||
+	    ($ENV{'request.state'} eq 'construct') ||
+	    ($Apache::lonhomework::browse eq 'F'
+	     &&
+	     $ENV{'form.show_errors'} eq 'on'));
+}
 
-    #FIXME probably shouldn't have me get everything forever.
-    &Apache::lonmsg::user_normal_msg('albertel','msu',"Error in $ENV{'request.filename'}",join('<br />',@_));
-    #&Apache::lonmsg::user_normal_msg('albertel','103',"Error in $ENV{'request.filename'}",$_[0]);
-  }
+sub error {
+    $errorcount++;
+    if ( &show_error_warn_msg() ) {
+	# If printing in construction space, put the error inside <pre></pre>
+	push(@Apache::lonxml::error_messages,
+	     $Apache::lonxml::warnings_error_header.
+	     "<b>ERROR:</b>".join("<br />\n",@_)."<br />\n");
+	$Apache::lonxml::warnings_error_header='';
+    } else {
+	my $errormsg;
+	my ($symb)=&Apache::lonnet::symbread();
+	if ( !$symb ) {
+	    #public or browsers
+	    $errormsg=&mt("An error occured while processing this resource. The author has been notified.");
+	} 
+	#notify author
+	&Apache::lonmsg::author_res_msg($ENV{'request.filename'},join('<br />',@_));
+	#notify course
+	if ( $symb && $ENV{'request.course.id'} ) {
+	    my (undef,%users)=&Apache::lonfeedback::decide_receiver(undef,0,1,1,1);
+	    my $declutter=&Apache::lonnet::declutter($ENV{'request.filename'});
+	    my @userlist;
+	    foreach (keys %users) {
+		my ($user,$domain) = split(/:/, $_);
+		push(@userlist,"$user\@$domain");
+		&Apache::lonmsg::user_normal_msg($user,$domain,
+						 "Error [$declutter]",join('<br />',@_));
+	    }
+	    if ($ENV{'request.role.adv'}) {
+		$errormsg=&mt("An error occured while processing this resource. The course personnel ([_1]) and the author have been notified.",join(', ',@userlist));
+	    } else {
+		$errormsg=&mt("An error occured while processing this resource. The instructor has been notified.");
+	    }
+	}
+	push(@Apache::lonxml::error_messages,"<b>$errormsg</b> <br />");
+    }
 }
 
 sub warning {
     $warningcount++;
   
     if ($ENV{'form.grade_target'} ne 'tex') {
-	if ($ENV{'request.state'} eq 'construct' || $Apache::lonxml::debug) {
+	if ( &show_error_warn_msg() ) {
 	    my $request=$Apache::lonxml::request;
 	    if (!$request) { $request=Apache->request; }
-	    $request->print($Apache::lonxml::warnings_error_header.
-		      "<b>W</b>ARNING<b>:</b>".join('<br />',@_)."<br />\n");
+	    push(@Apache::lonxml::warning_messages,
+		 $Apache::lonxml::warnings_error_header.
+		 "<b>W</b>ARNING<b>:</b>".join('<br />',@_)."<br />\n");
 	    $Apache::lonxml::warnings_error_header='';
 	}
     }
 }
 
+sub info {
+    if ($ENV{'form.grade_target'} ne 'tex' 
+	&& $ENV{'request.state'} eq 'construct') {
+	push(@Apache::lonxml::info_messages,join('<br />',@_)."<br />\n");
+    }
+}
+
+sub message_location {
+    return '__LONCAPA_INTERNAL_MESSAGE_LOCATION__';
+}
+
+sub add_messages {
+    my ($msg)=@_;
+    my $result=join(' ',
+		    @Apache::lonxml::info_messages,
+		    @Apache::lonxml::error_messages,
+		    @Apache::lonxml::warning_messages);
+    undef(@Apache::lonxml::info_messages);
+    undef(@Apache::lonxml::error_messages);
+    undef(@Apache::lonxml::warning_messages);
+    $$msg=~s/__LONCAPA_INTERNAL_MESSAGE_LOCATION__/$result/;
+    $$msg=~s/__LONCAPA_INTERNAL_MESSAGE_LOCATION__//g;
+}
+
 sub get_param {
     my ($param,$parstack,$safeeval,$context,$case_insensitive) = @_;
     if ( ! $context ) { $context = -1; }
@@ -1389,7 +1519,7 @@ sub get_param_var {
   } elsif ( $args !~ /my \$\Q$param\E=\"/ ) { return undef; }
   my $value=&Apache::run::run("{$args;".'return $'.$param.'}',$safeeval); #'
   &Apache::lonxml::debug("first run is $value");
-  if ($value =~ /^[\$\@\%]\w+$/) {
+  if ($value =~ /^[\$\@\%][a-zA-Z_]\w*$/) {
       &Apache::lonxml::debug("doing second");
       my @result=&Apache::run::run("return $value",$safeeval,1);
       if (!defined($result[0])) {
@@ -1477,29 +1607,36 @@ sub whichuser {
   my ($passedsymb)=@_;
   my ($symb,$courseid,$domain,$name,$publicuser);
   if (defined($ENV{'form.grade_symb'})) {
-    my $tmp_courseid=$ENV{'form.grade_courseid'};
-    my $allowed=&Apache::lonnet::allowed('vgr',$tmp_courseid);
-    if ($allowed) {
-      $symb=$ENV{'form.grade_symb'};
-      $courseid=$ENV{'form.grade_courseid'};
-      $domain=$ENV{'form.grade_domain'};
-      $name=$ENV{'form.grade_username'};
-    }
-  } else {
-      if (!$passedsymb) {
-          $symb=&Apache::lonnet::symbread();
-      } else {
-          $symb=$passedsymb;
+      my ($tmp_courseid)=
+	  &Apache::loncommon::get_env_multiple('form.grade_courseid');
+      my $allowed=&Apache::lonnet::allowed('vgr',$tmp_courseid);
+      if (!$allowed && 
+	  exists($ENV{'request.course.sec'}) && 
+	  $ENV{'request.course.sec'} !~ /^\s*$/) {
+	  $allowed=&Apache::lonnet::allowed('vgr',$tmp_courseid.
+					    '/'.$ENV{'request.course.sec'});
       }
-      $courseid=$ENV{'request.course.id'};
-      $domain=$ENV{'user.domain'};
-      $name=$ENV{'user.name'};
-      if ($name eq 'public' && $domain eq 'public') {
-	  if (!defined($ENV{'form.username'})) {
-	      $ENV{'form.username'}.=time.rand(10000000);
-	  }
-	  $name.=$ENV{'form.username'};
+      if ($allowed) {
+	  ($symb)=&Apache::loncommon::get_env_multiple('form.grade_symb');
+	  $courseid=$tmp_courseid;
+	  ($domain)=&Apache::loncommon::get_env_multiple('form.grade_domain');
+	  ($name)=&Apache::loncommon::get_env_multiple('form.grade_username');
+	  return ($symb,$courseid,$domain,$name,$publicuser);
+      }
+  }
+  if (!$passedsymb) {
+      $symb=&Apache::lonnet::symbread();
+  } else {
+      $symb=$passedsymb;
+  }
+  $courseid=$ENV{'request.course.id'};
+  $domain=$ENV{'user.domain'};
+  $name=$ENV{'user.name'};
+  if ($name eq 'public' && $domain eq 'public') {
+      if (!defined($ENV{'form.username'})) {
+	  $ENV{'form.username'}.=time.rand(10000000);
       }
+      $name.=$ENV{'form.username'};
   }
   return ($symb,$courseid,$domain,$name,$publicuser);
 }