--- loncom/interface/lonnavdisplay.pm	2024/10/14 01:34:57	1.44
+++ loncom/interface/lonnavdisplay.pm	2025/05/27 23:35:38	1.48
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Navigate Maps Display Handler
 #
-# $Id: lonnavdisplay.pm,v 1.44 2024/10/14 01:34:57 raeburn Exp $
+# $Id: lonnavdisplay.pm,v 1.48 2025/05/27 23:35:38 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -40,6 +40,7 @@ use Apache::lonlocal;
 use Apache::londocs();
 use Apache::lonuserstate;
 use LONCAPA::ltiutils;
+use LONCAPA;
 
 sub handler {
     my $r = shift;
@@ -129,7 +130,7 @@ ENDCLOSE
     my $course_type = &Apache::loncommon::course_type();
     if (($course_type eq 'Placement') && (!$env{'request.role.adv'})) { 
         my $furl = &Apache::lonpageflip::first_accessible_resource();
-        if ($result eq 'update') {
+        if (($result eq 'main') || ($result eq 'both')) {
             &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state);
             $r->print($closure.&Apache::loncommon::end_page());
             return OK;
@@ -160,7 +161,7 @@ ENDCLOSE
     my $navmap = Apache::lonnavmaps::navmap->new();
 
     if (!defined($navmap)) {
-        if ($result eq 'update') {
+        if (($result eq 'main') || ($result eq 'both')) {
             &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state);
             $r->print($closure.&Apache::loncommon::end_page());
         }
@@ -170,7 +171,7 @@ ENDCLOSE
         return HTTP_NOT_ACCEPTABLE;
     }
 
-    if ($result eq 'update') {
+    if (($result eq 'main') || ($result eq 'both')) {
         $r->rflush();
         &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state);
         $r->print($closure);
@@ -183,7 +184,7 @@ ENDCLOSE
     }
 
     &startContentScreen($r,'navmaps',$course_type);
-    unless ($result eq 'update') {
+    unless (($result eq 'main') || ($result eq 'both')) {
         $r->rflush();
     }
 
@@ -348,11 +349,88 @@ ENDCLOSE
     # If no resources were printed, print a reassuring message so the
     # user knows there was no error.
     if ($renderArgs->{'counter'} == 0) {
+        my $noresmsg;
         if ($showOnlyHomework) {
-            $r->print("<p><span class=\"LC_info\">".&mt("All homework is currently completed.")."</span></p>");
+            $noresmsg = &mt('All homework is currently completed.');
         } else { # both jumpToFirstHomework and normal use the same: course must be empty
-            $r->print("<p><span class=\"LC_info\">".&mt("This course is empty.")."</span></p>");
+            $noresmsg = &mt('This course is empty.');
+            if (($renderArgs->{'deeplinknolist'}) &&
+                ($env{'request.course.deeponlyprot'})) {
+                my ($linkprot,$currmatch,$othermatches,@names);
+                if ($env{'request.linkprot'}) {
+                    ($linkprot) = split(/:/,$env{'request.linkprot'});
+                }
+                foreach my $launcher (split(/&/,$env{'request.course.deeponlyprot'})) {
+                    my ($name,$itemnums) = split(/:/,$launcher);
+                    my @nums = split(/,/,$itemnums);
+                    if (($linkprot) &&
+                        (grep(/^\Q$linkprot\E$/,@nums))) {
+                        $currmatch = &LONCAPA::unescape($name);
+                        if (@nums > 1) {
+                            $othermatches = 1;
+                        }
+                    } else {
+                        push(@names,&LONCAPA::unescape($name));
+                    }
+                }
+                my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
+                my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
+                my $has_supp = &Apache::lonnet::has_unhidden_suppfiles($cnum,$cdom);
+                if ($linkprot) {
+                    if ($currmatch) {
+                        if ($has_supp) {
+                            $noresmsg = &mt('No main content available when accessed using the link you followed from [_1].',
+                                            $currmatch);
+                        } else {
+                            $noresmsg = &mt('No content available when accessed using the link you followed from [_1].',
+                                            $currmatch);
+                        }
+                        if ($othermatches) {
+                            $noresmsg = '<br />';
+                            if ($has_supp) {
+                                $noresmsg .= &mt('Main content may be available by following a different link from [_1].',
+                                                 $currmatch);
+                            } else {
+                                $noresmsg .= &mt('Content may be available by following a different link from [_1].',
+                                                 $currmatch); 
+                            }
+                        }
+                    } else {
+                        if ($has_supp) {
+                            $noresmsg = &mt('No main content available using the link you followed.');
+                        } else {
+                            $noresmsg = &mt('No content available using the link you followed.');
+                        }
+                    }
+                } elsif (@names > 0) {
+                    if ($has_supp) {
+                        $noresmsg = &mt('No main content available from direct login to this course.');
+                    } else {
+                        $noresmsg = &mt('No content available from direct login to this course.');
+                    }
+                }
+                if (@names == 1) {
+                    $noresmsg .= '<br />';
+                    if ($has_supp) {
+                        $noresmsg .= &mt('Main content is likely available by following links from [_1]',
+                                         $names[0]);
+                    } else {
+                        $noresmsg .= &mt('Content is likely available by following links from [_1]',
+                                         $names[0]);
+                    }
+                } elsif (@names > 1) {
+                    $noresmsg .= '<br />';
+                    if ($has_supp) {
+                        $noresmsg .= &mt('Main content is likely available by following links from the following: [_1]',
+                                         join(', ',@names));
+                    } else {
+                        $noresmsg .= &mt('Content is likely available by following links from the following: [_1]',
+                                         join(', ',@names));
+                    }
+                }
+            }
         }
+        $r->print('<p><span class="LC_info">'.$noresmsg.'</span></p>');
     }
     &endContentScreen($r);
     $r->print(&Apache::loncommon::end_page());
@@ -384,7 +462,8 @@ sub startpage {
 sub startContentScreen {
     my ($r,$mode,$course_type)=@_;
 
-    $r->print("\n".'<ul class="LC_TabContentBigger" id="mainnav">'."\n");
+    $r->print("\n".'<div class="LC_landmark" role="main">'.
+              '<ul class="LC_TabContentBigger" id="mainnav">'."\n");
     $r->print('<li'.(($mode eq 'navmaps')?' class="active"':'').'><a href="/adm/navmaps"><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;'.&mt('Main Content').'&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</b></a></li>'."\n");
     my $supptab;
     if ($env{'request.role.adv'}) {
@@ -407,7 +486,7 @@ sub startContentScreen {
 
 sub endContentScreen {
    my ($r)=@_;
-   $r->print('</div></div></div>');
+   $r->print('</div></div></div></div>');
 }
 
 1;