--- loncom/interface/lonmainmenu.pm	2013/04/17 01:30:15	1.10.2.1
+++ loncom/interface/lonmainmenu.pm	2021/06/07 06:05:49	1.13
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # displays the main menu
 #
-# $Id: lonmainmenu.pm,v 1.10.2.1 2013/04/17 01:30:15 raeburn Exp $
+# $Id: lonmainmenu.pm,v 1.13 2021/06/07 06:05:49 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -35,13 +35,23 @@
 package Apache::lonmainmenu;
 
 use strict;
-use Apache::Constants qw(:common);
+use Apache::Constants qw(:common REDIRECT);
 use Apache::loncommon();
 use Apache::lonnet;
 use Apache::lonmenu();
+use Apache::lonlocal;
 
 sub handler {
     my $r = shift;
+
+    # Check for critical messages and redirect if present.  
+    my ($redirect,$url) = &Apache::loncommon::critical_redirect(300,'menu');
+    if ($redirect) {
+        &Apache::loncommon::content_type($r,'text/html');
+        $r->header_out(Location => $url);
+        return REDIRECT;
+    }
+
     &Apache::loncommon::no_cache($r);
     &Apache::loncommon::content_type($r,'text/html');
     $r->send_http_header;
@@ -51,10 +61,31 @@ sub handler {
 # temporarily set interface to "faketextual" and remote to "off", which renders
 # the main menu
     $env{'browser.interface'}='faketextual';
-    $env{'environment.remote'}='off';
+
     $r->print(&Apache::loncommon::start_page( 'Main Menu',
                                                undef,
                                               {'bread_crumbs' => 1}));
+#
+# If menu collection is in effect in course context, and Main Menu is 
+# not included, display message in place of usual menu items.
+#
+    if ($env{'request.course.id'}) {
+        my ($menucoll,$deeplinkmenu,$menuref) =
+            &Apache::loncommon::menucoll_in_effect();
+        if ($menucoll) {
+            if (ref($menuref) eq 'HASH') {
+                if ($menuref->{'main'} eq 'n') {
+                    $r->print('<h3>'.&mt('Main Menu unavailable').'</h3>');
+                    unless ($deeplinkmenu) {
+                        my $crstype = &Apache::loncommon::course_type();
+                        $r->print('<p>'.&mt("Main Menu page is unavailable in this $crstype").'</p>');
+                    }
+                    $r->print(&Apache::loncommon::end_page());
+                    return OK;
+                }
+            }
+        }
+    }
     $r->print(&Apache::lonmenu::inlinemenu());
     $r->print(&Apache::loncommon::end_page());
     return OK;