--- loncom/xml/lonxml.pm	2017/11/16 23:54:43	1.531.2.22.2.1
+++ loncom/xml/lonxml.pm	2023/12/29 23:40:37	1.531.2.24.2.1
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # XML Parser Module 
 #
-# $Id: lonxml.pm,v 1.531.2.22.2.1 2017/11/16 23:54:43 raeburn Exp $
+# $Id: lonxml.pm,v 1.531.2.24.2.1 2023/12/29 23:40:37 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -69,6 +69,8 @@ use Safe();
 use Safe::Hole();
 use Math::Cephes();
 use Math::Random();
+use Math::Calculus::Expression();
+use Number::FormatEng();
 use Opcode();
 use POSIX qw(strftime);
 use Time::HiRes qw( gettimeofday tv_interval );
@@ -440,7 +442,7 @@ sub latex_special_symbols {
     } else {
 	$string=~s/\\/\\ensuremath{\\backslash}/g;
 	$string=~s/\\\%|\%/\\\%/g;
-	$string=~s/\\\{|{/\\{/g;
+	$string=~s/\\\{|\{/\\{/g;
 	$string=~s/\\}|}/\\}/g;
 	$string=~s/\\ensuremath\\\{\\backslash\\}/\\ensuremath{\\backslash}/g;
 	$string=~s/\\\$|\$/\\\$/g;
@@ -914,6 +916,9 @@ sub init_safespace {
   $safehole->wrap(\&Apache::functionplotresponse::fpr_objectcoords,$safeeval,'&fpr_objectcoords');
   $safehole->wrap(\&Apache::functionplotresponse::fpr_vectorlength,$safeeval,'&fpr_vectorlength');
   $safehole->wrap(\&Apache::functionplotresponse::fpr_vectorangle,$safeeval,'&fpr_vectorangle');
+  $safehole->wrap(\&Math::Calculus::Expression::math_calculus_expression,$safeeval,'&math_calculus_expression');
+  $safehole->wrap(\&Number::FormatEng::format_eng,$safeeval,'&number_format_eng');
+  $safehole->wrap(\&Number::FormatEng::format_pref,$safeeval,'&number_format_pref');
 
 #  use Data::Dumper;
 #  $safehole->wrap(\&Data::Dumper::Dumper,$safeeval,'&LONCAPA_INTERNAL_Dumper');
@@ -1086,7 +1091,7 @@ sub decreasedepth {
 sub get_id {
     my ($parstack,$safeeval)=@_;
     my $id= &Apache::lonxml::get_param('id',$parstack,$safeeval);
-    if ($env{'request.state'} eq 'construct' && $id =~ /([._]|[^\w\d\s[:punct:]])/) {
+    if ($env{'request.state'} eq 'construct' && $id =~ /([._]|[^\w\s\-])/) { 
 	&error(&mt('ID [_1] contains invalid characters. IDs are only allowed to contain letters, numbers, spaces and -','"<tt>'.$id.'</tt>"'));
     }
     if ($id =~ /^\s*$/) { $id = $Apache::lonxml::curdepth; }
@@ -1720,14 +1725,23 @@ FULLPAGE
               }
           }
       }
-      my $undo;
+      my ($undo,%onclick);
+      foreach my $item ('discard','undo','daxe') {
+          $onclick{$item} = 'onclick="still_ask=true;setmode(this.form,'."'$item'".')"';
+      }
+      foreach my $item ('saveedit','saveview') {
+          $onclick{$item} = 'onclick="is_submit=true;setmode(this.form,'."'$item'".')"';
+      }
       unless ($uri =~ m{^/uploaded/}) {
-          $undo = '<input type="submit" name="Undo" accesskey="u" value="'.$lt{'un'}.'" />'."\n";
+          $undo = '<input type="button" name="Undo" accesskey="u" value="'.$lt{'un'}.'" '.
+                  $onclick{'undo'}.' />'."\n";
       }
+      $initialize .= &setmode_javascript();
       my $editfooter=(<<ENDFOOTER);
 $initialize
 <a name="editsection" />
 <form $form_events method="post" name="xmledit" action="$action">
+  <input type="hidden" name="problemmode" value="edit" />
   <div class="LC_edit_problem_editxml_header">
     <table class="LC_edit_problem_header_title"><tr><td>
         $filename
@@ -1735,14 +1749,14 @@ $initialize
         $xml_help
       </td></tr>
     </table>
+    <div style="float:right">
+      <input type="button" name="savethisfile" accesskey="s" value="$lt{'st'}" $onclick{'saveedit'} />
+      <input type="button" name="viewmode" accesskey="v" value="$lt{'vi'}" $onclick{'saveview'} />
+    </div>
     <div>
-      <input type="submit" name="discardview" accesskey="d" value="$lt{'dv'}" />
+      <input type="button" name="discardview" accesskey="d" value="$lt{'dv'}" $onclick{'discard'} />
       $undo $htmlerror $deps_button $dragmath_button
     </div>
-    <div style="float:right">
-      <input type="submit" name="savethisfile" accesskey="s" value="$lt{'st'}" />
-      <input type="submit" name="viewmode" accesskey="v" value="$lt{'vi'}" />
-    </div>
   </div>
   <textarea $textarea_events style="width:100%" cols="80" rows="44" name="filecont" id="filecont" $textareaclass>$filecontents</textarea><br />$spelllink
   <div id="LC_aftertextarea">
@@ -1751,7 +1765,35 @@ $initialize
   </div>
 </form>
 ENDFOOTER
-      return ($editfooter,$add_to_onload,$add_to_onresize);;
+      return ($editfooter,$add_to_onload,$add_to_onresize);
+}
+
+sub setmode_javascript {
+    return <<"ENDSCRIPT";
+<script type="text/javascript">
+// <![CDATA[
+function setmode(form,probmode) {
+    var initial = form.problemmode.value;
+    form.problemmode.value = probmode;
+    form.submit();
+    form.problemmode.value = initial;
+}
+// ]]>
+</script>
+ENDSCRIPT
+}
+
+sub seteditor_javascript {
+    return <<"ENDSCRIPT";
+<script type="text/javascript">
+// <![CDATA[
+function seteditmode(form,editor) {
+    form.editmode.value = editor;
+    form.submit();
+}
+// ]]>
+</script>
+ENDSCRIPT
 }
 
 sub get_target {
@@ -1856,11 +1898,13 @@ sub handler {
 # Edit action? Save file.
 #
     if (!($env{'request.state'} eq 'published')) {
-	if ($env{'form.savethisfile'} || $env{'form.viewmode'} || $env{'form.Undo'}) {
+        if (($env{'form.problemmode'} eq 'saveedit') ||
+            ($env{'form.problemmode'} eq 'saveview') ||
+            ($env{'form.problemmode'} eq 'undo')) {
 	    my $html_file=&Apache::lonnet::getfile($file);
 	    my $error = &Apache::lonhomework::handle_save_or_undo($request, \$html_file, \$env{'form.filecont'});
-            if ($env{'form.savethisfile'}) {
-                $env{'form.editmode'}='Edit'; #force edit mode
+            if ($env{'form.problemmode'} eq 'saveedit') {
+                $env{'form.editmode'}='edit'; #force edit mode
             }
 	}
     }
@@ -1889,7 +1933,7 @@ ENDNOTFOUND
             } elsif ($filetype ne 'css' && $filetype ne 'txt' && $filetype ne 'tex') {
 		$filecontents=&createnewhtml();
 	    }
-	    $env{'form.editmode'}='Edit'; #force edit mode
+	    $env{'form.editmode'}='edit'; #force edit mode
 	}
     } else {
 	unless ($env{'request.state'} eq 'published') {
@@ -1901,7 +1945,9 @@ ENDNOTFOUND
             &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
 						    ['editmode']);
 	}
-	if (!$env{'form.editmode'} || $env{'form.viewmode'} || $env{'form.discardview'}) {
+	if ((!$env{'form.editmode'}) ||
+            ($env{'form.problemmode'} eq 'saveview') ||
+            ($env{'form.problemmode'} eq 'discard')) {
             if ($filetype eq 'html' || $filetype eq 'sty') {
 	        &Apache::structuretags::reset_problem_globals();
 	        $result = &Apache::lonxml::xmlparse($request,$target,
@@ -1969,8 +2015,9 @@ ENDNOTFOUND
 # Edit action? Insert editing commands
 #
     unless (($env{'request.state'} eq 'published') || ($inhibit_menu)) {
-	if ($env{'form.editmode'} && (!($env{'form.viewmode'})) && (!($env{'form.discardview'})))
-	{
+	if (($env{'form.editmode'}) &&
+            (!($env{'form.problemmode'} eq 'saveview')) &&
+            (!($env{'form.problemmode'} eq 'discard'))) {
             my ($displayfile,$url,$symb,$itemtitle,$action);
 	    $displayfile=$request->uri;
             if ($request->uri =~ m{^/uploaded/}) {