--- loncom/interface/lonpreferences.pm	2021/03/06 19:44:54	1.196.4.27
+++ loncom/interface/lonpreferences.pm	2021/03/06 19:44:12	1.238
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Preferences
 #
-# $Id: lonpreferences.pm,v 1.196.4.27 2021/03/06 19:44:54 raeburn Exp $
+# $Id: lonpreferences.pm,v 1.238 2021/03/06 19:44:12 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -165,7 +165,7 @@ sub texenginechanger {
     my %mathchoices=('' => 'Default',
 		     'tth' => 'tth (TeX to HTML)',
 		     #'ttm' => 'TeX to MathML',
-                     'MathJax' => 'MathJax',
+		     'MathJax' => 'MathJax',
 		     'mimetex' => 'mimetex (Convert to Images)',
                      'raw' => 'Raw (Screen Reader)'
                      );
@@ -182,7 +182,7 @@ sub texenginechanger {
       'change'   => 'Save',
       'exmpl'    => 'Examples',
       'mathjax'  => 'MathJax:',
-      'mathjaxinfo' =>  'MathJax provides rendered equations whose source code can be extracted in TeX and MathML formats by right clicking the equation.',
+      'mathjaxinfo' => 'MathJax provides rendered equations whose source code can be extracted in TeX and MathML formats by right clicking the equation.',
       'tth'      => 'tth (TeX to HTML):',
       'mimetex'  => 'mimetex (Convert to Images):',
     );
@@ -280,7 +280,7 @@ sub rolesprefchanger {
     my $hotlist_n=$userenv{'recentrolesn'};
     my ($checkedon,$checkedoff);
     if ($hotlist_flag) {
-        $checkedon = 'checked="checked"'; 
+	$checkedon = 'checked="checked"';
     } else {
         $checkedoff = 'checked="checked"';
     }
@@ -683,16 +683,51 @@ sub verify_and_change_clicker {
     my $r = shift;
     my $user       = $env{'user.name'};
     my $domain     = $env{'user.domain'};
+    my $uhome      = $env{'user.home'};
     my $newclickers  = $env{'form.clickers'};
+    my $message;
     $newclickers=~s/[^\w\:\-]+/\,/gs;
     $newclickers=~tr/a-z/A-Z/;
     $newclickers=~s/[\:\-]+/\-/g;
     $newclickers=~s/\,+/\,/g;
     $newclickers=~s/^\,//;
     $newclickers=~s/\,$//;
-    &Apache::lonnet::put('environment',{'clickers' => $newclickers});
-    &Apache::lonnet::appenv({'environment.clickers' => $newclickers});
-    my $message=&Apache::lonhtmlcommon::confirm_success(&mt('Registering clickers: [_1]',$newclickers));
+    my @oldclickers = split(/,/,$env{'environment.clickers'});
+    my @newclickers = split(/,/,$newclickers);
+    my %newuniq;
+    map { $newuniq{$_} = 1; }  @newclickers;
+    @newclickers = sort(keys(%newuniq));
+    my @differences = &Apache::loncommon::compare_arrays(\@oldclickers,\@newclickers);
+    if (@differences) {
+        my $putres = &Apache::lonnet::put('environment',{'clickers' => $newclickers});
+        if ($putres eq 'ok') {
+            my @adds = ();
+            my @dels = ();
+            foreach my $item (@differences) {
+                if (grep(/^\Q$item\E$/,@newclickers)) {
+                    push(@adds,$item);
+                } else {
+                    push(@dels,$item);
+                }
+            }
+            if (@dels) {
+                 my %delclicker;
+                 map { $delclicker{$_} = $user; } @dels;
+                 my $putresult = &Apache::lonnet::iddel($domain,\%delclicker,$uhome,'clickers');
+            }
+            if (@adds) {
+                 my %addclicker;
+                 map { $addclicker{$_} = $user; } @adds;
+                 my $putresult = &Apache::lonnet::updateclickers($domain,'add',\%addclicker,$uhome,1);
+            }
+            &Apache::lonnet::appenv({'environment.clickers' => $newclickers});
+            $message=&Apache::lonhtmlcommon::confirm_success(&mt('Registering clickers: [_1]',$newclickers));
+        } else {
+            $message=&Apache::lonhtmlcommon::confirm_success(&mt('Error saving clicker ID').1);
+        }
+    } else {
+        $message='<span class="LC_info">'.&mt('Clicker information unchanged').'</span>';
+    }
     $message=&Apache::loncommon::confirmwrapper($message);
     &print_main_menu($r, $message);
 }
@@ -1142,10 +1177,10 @@ sub colorschanger {
     foreach my $item (sort(keys(%colortypes))) {
        my $curcol=&Apache::loncommon::designparm($function.'.'.$item,$domain);
        $chtable.=&Apache::loncommon::start_data_table_row().
-                 '<td>'.$colortypes{$item}.'<td><input name="'.$item.
-                 '" class="colorchooser"  size="10" value="'.$curcol.
-                 '" /></td>'.
-	         &Apache::loncommon::end_data_table_row()."\n";
+	   '<td>'.$colortypes{$item}.'<td><input name="'.$item.
+        '" class="colorchooser"  size="10" value="'.$curcol.
+'" /></td>'.
+	    &Apache::loncommon::end_data_table_row()."\n";
     }
     my $end_data_table = &Apache::loncommon::end_data_table();
     my $pjump_def = &Apache::lonhtmlcommon::pjump_javascript_definition();
@@ -1197,9 +1232,9 @@ sub verify_and_change_colors {
     my $message='';
     foreach my $item (keys(%colortypes)) {
         my $color=$env{'form.'.$item};
-        if (!($color =~ /^#/)) {
-            $color = '#' . $color;
-        }
+	if (!($color =~ /^#/)) {
+	    $color = '#' . $color;
+	}
         my $entry='color.'.$function.'.'.$item;
 	if (($color=~/^\#[0-9A-Fa-f]{6}$/) && (!$env{'form.resetall'})) {
 	    &Apache::lonnet::put('environment',{$entry => $color});
@@ -1284,9 +1319,9 @@ sub passwordchanger {
         } else {
             $r->print(
                 '<p class="LC_warning">'
-                .&mt('Sorry, the URL generated when you requested reset of'
-                    .' your password contained incomplete information.')
-                .'</p>'
+               .&mt('Sorry, the URL generated when you requested reset of'
+                   .' your password contained incomplete information.')
+               .'</p>'
             );
             return;
         }
@@ -1401,7 +1436,7 @@ sub jscript_send {
             var posspass = this.document.client.elements.newpass_1.value;
             if (min > 0) {
                 if (posspass.length < min) {
-                    errors.push("$js_lt{'short'}"); 
+                    errors.push("$js_lt{'short'}");
                 }
             }
             if (currauth == 'internal:') {
@@ -1430,7 +1465,7 @@ sub jscript_send {
                         } else if (rules[i] == 'spec') {
                             var pattern = /^[!@#$%^&*()_+\\-=\\[\\]{};':"\\\|,.<a>\\/?]/;
                             if (!posspass.match(pattern)) {
-                                errors.push("$js_lt{'spec'}"); 
+                                errors.push("$js_lt{'spec'}");
                             }
                         }
                     }
@@ -1723,10 +1758,10 @@ ENDERROR
     } else {
         my $warning = &Apache::loncommon::check_passwd_rules($domain,$newpass1);
         if ($warning) {
-	    &passwordchanger($r,'<span class="LC_warning">'.
-                             $warning.
-			     &mt('Please try again.').'</span>',
-                             $caller,$mailtoken,$timelimit,$extrafields);
+            &passwordchanger($r,'<span class="LC_warning">'.
+                            $warning.
+                            &mt('Please try again.').'</span>',
+                            $caller,$mailtoken,$timelimit,$extrafields);
             if ($caller eq 'reset_by_email') {
                 return 'rules';
             } else {
@@ -2294,25 +2329,6 @@ push(@{ $menu[0]->{items} }, {
 	linktitle => 'Change your password.',
 	});
     }
-    if ($env{'environment.remote'} eq 'off') {
-push(@{ $menu[1]->{items} }, {
-        linktext => 'Launch Remote Control',
-        url => '/adm/remote?url=/adm/preferences&amp;action=launch',
-        permission => 'F',
-        #help => '',
-        icon => 'remotecontrol.png',
-        linktitle => 'Launch the remote control for LON-CAPA.',
-        });
-    }else{
-push(@{ $menu[1]->{items} }, {
-        linktext => 'Collapse Remote Control',
-        url => '/adm/remote?url=/adm/preferences&amp;action=collapse',
-        permission => 'F',
-        #help => '',
-        icon => 'remotecontrol.png',
-        linktitle => 'Collapse the remote control for LON-CAPA.',
-        });
-    }
 
     if (&can_toggle_namelocking()) {
         push(@{ $menu[0]->{items} }, {
@@ -2425,8 +2441,8 @@ sub handler {
           text => $brtxt,
           help => $brhelp,});
     if(!exists $env{'form.action'}) {
-	    &print_main_menu($r);
-            $ended = 1;
+	&print_main_menu($r);
+        $ended = 1;
     }elsif($env{'form.action'} eq 'changepass'){
         &passwordchanger($r);
     }elsif($env{'form.action'} eq 'verify_and_change_pass'){