--- loncom/interface/loncommon.pm	2019/02/04 01:32:50	1.1075.2.127.2.6
+++ loncom/interface/loncommon.pm	2020/07/17 22:17:17	1.1075.2.127.2.11
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # a pile of common routines
 #
-# $Id: loncommon.pm,v 1.1075.2.127.2.6 2019/02/04 01:32:50 raeburn Exp $
+# $Id: loncommon.pm,v 1.1075.2.127.2.11 2020/07/17 22:17:17 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -82,6 +82,8 @@ use Crypt::DES;
 use DynaLoader; # for Crypt::DES version
 use File::Copy();
 use File::Path();
+use String::CRC32();
+use Short::URL();
 
 # ---------------------------------------------- Designs
 use vars qw(%defaultdesign);
@@ -4614,7 +4616,8 @@ sub blockcheck {
     # boards, chat or groups, check for blocking in current course only.
 
     if (($activity eq 'boards' || $activity eq 'chat' ||
-         $activity eq 'groups' || $activity eq 'printout') &&
+         $activity eq 'groups' || $activity eq 'printout' ||
+         $activity eq 'reinit' || $activity eq 'alert') &&
         ($env{'request.course.id'})) {
         foreach my $key (keys(%live_courses)) {
             if ($key ne $env{'request.course.id'}) {
@@ -4925,6 +4928,10 @@ END_MYBLOCK
         $text = &mt('Printing Blocked');
     } elsif ($activity eq 'passwd') {
         $text = &mt('Password Changing Blocked');
+    } elsif ($activity eq 'alert') {
+        $text = &mt('Checking Critical Messages Blocked');
+    } elsif ($activity eq 'reinit') {
+        $text = &mt('Checking Course Update Blocked');
     }
     $output .= <<"END_BLOCK";
 <div class='$class'>
@@ -14927,7 +14934,8 @@ sub check_clone {
     my $cloneid='/'.$args->{'clonedomain'}.'/'.$args->{'clonecourse'};
     my ($clonecrsudom,$clonecrsunum)= &LONCAPA::split_courseid($cloneid);
     my $clonehome=&Apache::lonnet::homeserver($clonecrsunum,$clonecrsudom);
-    my $clonemsg;
+    my $clonetitle;
+    my @clonemsg;
     my $can_clone = 0;
     my $lctype = lc($args->{'crstype'});
     if ($lctype ne 'community') {
@@ -14935,16 +14943,38 @@ sub check_clone {
     }
     if ($clonehome eq 'no_host') {
         if ($args->{'crstype'} eq 'Community') {
-            $clonemsg = &mt('No new community created.').$linefeed.&mt('A new community could not be cloned from the specified original - [_1] - because it is a non-existent community.',$args->{'clonecourse'}.':'.$args->{'clonedomain'});
+            push(@clonemsg,({
+                              mt => 'No new community created.',
+                              args => [],
+                            },
+                            {
+                              mt => 'A new community could not be cloned from the specified original - [_1] - because it is a non-existent community.',
+                              args => [$args->{'clonedomain'}.':'.$args->{'clonedomain'}],
+                            }));
         } else {
-            $clonemsg = &mt('No new course created.').$linefeed.&mt('A new course could not be cloned from the specified original - [_1] - because it is a non-existent course.',$args->{'clonecourse'}.':'.$args->{'clonedomain'});
-        }     
+            push(@clonemsg,({
+                              mt => 'No new course created.',
+                              args => [],
+                            },
+                            {
+                              mt => 'A new course could not be cloned from the specified original - [_1] - because it is a non-existent course.',
+                              args => [$args->{'clonecourse'}.':'.$args->{'clonedomain'}],
+                            }));
+        }
     } else {
 	my %clonedesc = &Apache::lonnet::coursedescription($cloneid,{'one_time' => 1});
+        $clonetitle = $clonedesc{'description'};
         if ($args->{'crstype'} eq 'Community') {
             if ($clonedesc{'type'} ne 'Community') {
-                 $clonemsg = &mt('No new community created.').$linefeed.&mt('A new community could not be cloned from the specified original - [_1] - because it is a course not a community.',$args->{'clonecourse'}.':'.$args->{'clonedomain'});
-                return ($can_clone, $clonemsg, $cloneid, $clonehome);
+                push(@clonemsg,({
+                                  mt => 'No new community created.',
+                                  args => [],
+                                },
+                                {
+                                  mt => 'A new community could not be cloned from the specified original - [_1] - because it is a course not a community.',
+                                  args => [$args->{'clonecourse'}.':'.$args->{'clonedomain'}],
+                                }));
+                return ($can_clone,\@clonemsg,$cloneid,$clonehome);
             }
         }
 	if (($env{'request.role.domain'} eq $args->{'clonedomain'}) &&
@@ -15033,20 +15063,34 @@ sub check_clone {
             }
             unless ($can_clone) {
                 if ($args->{'crstype'} eq 'Community') {
-                    $clonemsg = &mt('No new community created.').$linefeed.&mt('The new community could not be cloned from the existing community because the new community owner ([_1]) does not have cloning rights in the existing community ([_2]).',$args->{'ccuname'}.':'.$args->{'ccdomain'},$clonedesc{'description'});
+                    push(@clonemsg,({
+                                      mt => 'No new community created.',
+                                      args => [],
+                                    },
+                                    {
+                                      mt => 'The new community could not be cloned from the existing community because the new community owner ([_1]) does not have cloning rights in the existing community ([_2]).',
+                                      args => [$args->{'ccuname'}.':'.$args->{'ccdomain'},$clonedesc{'description'}],
+                                    }));
                 } else {
-                    $clonemsg = &mt('No new course created.').$linefeed.&mt('The new course could not be cloned from the existing course because the new course owner ([_1]) does not have cloning rights in the existing course ([_2]).',$args->{'ccuname'}.':'.$args->{'ccdomain'},$clonedesc{'description'});
-	        }
+                    push(@clonemsg,({
+                                      mt => 'No new course created.',
+                                      args => [],
+                                    },
+                                    {
+                                      mt => 'The new course could not be cloned from the existing course because the new course owner ([_1]) does not have cloning rights in the existing course ([_2]).',
+                                      args => [$args->{'ccuname'}.':'.$args->{'ccdomain'},$clonedesc{'description'}],
+                                    }));
+                }
 	    }
         }
     }
-    return ($can_clone, $clonemsg, $cloneid, $clonehome);
+    return ($can_clone,\@clonemsg,$cloneid,$clonehome,$clonetitle);
 }
 
 sub construct_course {
     my ($args,$logmsg,$courseid,$crsudom,$crsunum,$udom,$uname,$context,
-        $cnum,$category,$coderef) = @_;
-    my $outcome;
+        $cnum,$category,$coderef,$callercontext,$user_lh) = @_;
+    my ($outcome,$msgref,$clonemsgref);
     my $linefeed =  '<br />'."\n";
     if ($context eq 'auto') {
         $linefeed = "\n";
@@ -15055,18 +15099,11 @@ sub construct_course {
 #
 # Are we cloning?
 #
-    my ($can_clone, $clonemsg, $cloneid, $clonehome);
+    my ($can_clone,$cloneid,$clonehome,$clonetitle);   
     if (($args->{'clonecourse'}) && ($args->{'clonedomain'})) {
-	($can_clone, $clonemsg, $cloneid, $clonehome) = &check_clone($args,$linefeed);
-	if ($context ne 'auto') {
-            if ($clonemsg ne '') {
-	        $clonemsg = '<span class="LC_error">'.$clonemsg.'</span>';
-            }
-	}
-	$outcome .= $clonemsg.$linefeed;
-
+	($can_clone,$clonemsgref,$cloneid,$clonehome,$clonetitle) = &check_clone($args,$linefeed); 
         if (!$can_clone) {
-	    return (0,$outcome);
+	    return (0,$outcome,$clonemsgref);
 	}
     }
 
@@ -15084,15 +15121,20 @@ sub construct_course {
                                              $args->{'ccuname'}.':'.
                                              $args->{'ccdomain'},
                                              $args->{'crstype'},
-                                             $cnum,$context,$category);
+                                             $cnum,$context,$category,
+                                             $callercontext);
 
     # Note: The testing routines depend on this being output; see 
     # Utils::Course. This needs to at least be output as a comment
     # if anyone ever decides to not show this, and Utils::Course::new
     # will need to be suitably modified.
-    $outcome .= &mt('New LON-CAPA [_1] ID: [_2]',$crstype,$$courseid).$linefeed;
+    if (($callercontext eq 'auto') && ($user_lh ne '')) {
+        $outcome .= &mt_user($user_lh,'New LON-CAPA [_1] ID: [_2]',$crstype,$$courseid).$linefeed;
+    } else {
+        $outcome .= &mt('New LON-CAPA [_1] ID: [_2]',$crstype,$$courseid).$linefeed;
+    }
     if ($$courseid =~ /^error:/) {
-        return (0,$outcome);
+        return (0,$outcome,$clonemsgref);
     }
 
 #
@@ -15101,23 +15143,37 @@ sub construct_course {
     ($$crsudom,$$crsunum)= &LONCAPA::split_courseid($$courseid);
     my $crsuhome=&Apache::lonnet::homeserver($$crsunum,$$crsudom);
     if ($crsuhome eq 'no_host') {
-        $outcome .= &mt('Course creation failed, unrecognized course home server.').$linefeed;
-        return (0,$outcome);
+        if (($callercontext eq 'auto') && ($user_lh ne '')) {
+            $outcome .= &mt_user($user_lh,
+                            'Course creation failed, unrecognized course home server.');
+        } else {
+            $outcome .= &mt('Course creation failed, unrecognized course home server.');
+        }
+        $outcome .= $linefeed;
+        return (0,$outcome,$clonemsgref);
     }
     $outcome .= &mt('Created on').': '.$crsuhome.$linefeed;
 
 #
 # Do the cloning
 #   
+    my @clonemsg;
     if ($can_clone && $cloneid) {
-	$clonemsg = &mt('Cloning [_1] from [_2]',$crstype,$clonehome);
-	if ($context ne 'auto') {
-	    $clonemsg = '<span class="LC_success">'.$clonemsg.'</span>';
-	}
-	$outcome .= $clonemsg.$linefeed;
+        push(@clonemsg,
+                      {
+                          mt => 'Created [_1] by cloning from [_2]',
+                          args => [$crstype,$clonetitle],
+                      });
 	my %oldcenv=&Apache::lonnet::dump('environment',$$crsudom,$$crsunum);
 # Copy all files
-	&Apache::lonclonecourse::copycoursefiles($cloneid,$$courseid,$args->{'datemode'},$args->{'dateshift'});
+        my @info =
+	    &Apache::lonclonecourse::copycoursefiles($cloneid,$$courseid,$args->{'datemode'},
+                                                     $args->{'dateshift'},$args->{'crscode'},
+                                                     $args->{'ccuname'}.':'.$args->{'ccdomain'},
+                                                     $args->{'tinyurls'});
+        if (@info) {
+            push(@clonemsg,@info);
+        }
 # Restore URL
 	$cenv{'url'}=$oldcenv{'url'};
 # Restore title
@@ -15419,7 +15475,7 @@ sub construct_course {
         $outcome .= ($fatal?$errtext:'write ok').$linefeed;
     }
 
-    return (1,$outcome);
+    return (1,$outcome,\@clonemsg);
 }
 
 sub make_unique_code {
@@ -16551,8 +16607,12 @@ sub needs_coursereinit {
         $interval = 600;
     }
     if (($now-$env{'request.course.timechecked'})>$interval) {
-        my $lastchange = &Apache::lonnet::get_coursechange($cdom,$cnum);
         &Apache::lonnet::appenv({'request.course.timechecked'=>$now});
+        my $blocked = &blocking_status('reinit',$cnum,$cdom,undef,1);
+        if ($blocked) {
+            return ();
+        }
+        my $lastchange = &Apache::lonnet::get_coursechange($cdom,$cnum);
         if ($lastchange > $env{'request.course.tied'}) {
             my %curr_reqd_hash = &Apache::lonnet::userenvironment($cdom,$cnum,'internal.releaserequired');
             if ($curr_reqd_hash{'internal.releaserequired'} ne '') {
@@ -16987,9 +17047,25 @@ sub cleanup_html {
 
 # Checks for critical messages and returns a redirect url if one exists.
 # $interval indicates how often to check for messages.
+# $context is the calling context -- roles, grades, contents, menu or flip.
 sub critical_redirect {
-    my ($interval) = @_;
+    my ($interval,$context) = @_;
     if ((time-$env{'user.criticalcheck.time'})>$interval) {
+        if (($env{'request.course.id'}) && (($context eq 'flip') || ($context eq 'contents'))) {
+            my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
+            my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
+            my $blocked = &blocking_status('alert',$cnum,$cdom,undef,1);
+            if ($blocked) {
+                my $checkrole = "cm./$cdom/$cnum";
+                if ($env{'request.course.sec'} ne '') {
+                    $checkrole .= "/$env{'request.course.sec'}";
+                }
+                unless ((&Apache::lonnet::allowed('evb',undef,undef,$checkrole)) &&
+                        ($env{'request.role'} !~ m{^st\./$cdom/$cnum})) {
+                    return;
+                }
+            }
+        }
         my @what=&Apache::lonnet::dump('critical', $env{'user.domain'},
                                         $env{'user.name'});
         &Apache::lonnet::appenv({'user.criticalcheck.time'=>time});
@@ -17055,6 +17131,157 @@ sub des_decrypt {
     return $plaintext;
 }
 
+sub get_requested_shorturls {
+    my ($cdom,$cnum,$navmap) = @_;
+    return unless (ref($navmap));
+    my ($numnew,$errors);
+    my @toshorten = &Apache::loncommon::get_env_multiple('form.addtiny');
+    if (@toshorten) {
+        my (%maps,%resources,%titles);
+        &Apache::loncourserespicker::enumerate_course_contents($navmap,\%maps,\%resources,\%titles,
+                                                               'shorturls',$cdom,$cnum);
+        if (keys(%resources)) {
+            my %tocreate;
+            foreach my $item (sort {$a <=> $b} (@toshorten)) {
+                my $symb = $resources{$item};
+                if ($symb) {
+                    $tocreate{$cnum.'&'.$symb} = 1;
+                }
+            }
+            if (keys(%tocreate)) {
+                ($numnew,$errors) = &make_short_symbs($cdom,$cnum,
+                                                      \%tocreate);
+            }
+        }
+    }
+    return ($numnew,$errors);
+}
+
+sub make_short_symbs {
+    my ($cdom,$cnum,$tocreateref,$lockuser) = @_;
+    my ($numnew,@errors);
+    if (ref($tocreateref) eq 'HASH') {
+        my %tocreate = %{$tocreateref};
+        if (keys(%tocreate)) {
+            my %coursetiny = &Apache::lonnet::dump('tiny',$cdom,$cnum);
+            my $su = Short::URL->new(no_vowels => 1);
+            my $init = '';
+            my (%newunique,%addcourse,%courseonly,%failed);
+            # get lock on tiny db
+            my $now = time;
+            if ($lockuser eq '') {
+                $lockuser = $env{'user.name'}.':'.$env{'user.domain'};
+            }
+            my $lockhash = {
+                                "lock\0$now" => $lockuser,
+                            };
+            my $tries = 0;
+            my $gotlock = &Apache::lonnet::newput_dom('tiny',$lockhash,$cdom);
+            my ($code,$error);
+            while (($gotlock ne 'ok') && ($tries<3)) {
+                $tries ++;
+                sleep 1;
+                $gotlock = &Apache::lonnet::newput_dom('tiny',$lockhash,$cdom);
+            }
+            if ($gotlock eq 'ok') {
+                $init = &shorten_symbs($cdom,$init,$su,\%coursetiny,\%tocreate,\%newunique,
+                                       \%addcourse,\%courseonly,\%failed);
+                if (keys(%failed)) {
+                    my $numfailed = scalar(keys(%failed));
+                    push(@errors,&mt('error: could not obtain unique six character URL for [quant,_1,resource]',$numfailed));
+                }
+                if (keys(%newunique)) {
+                    my $putres = &Apache::lonnet::newput_dom('tiny',\%newunique,$cdom);
+                    if ($putres eq 'ok') {
+                        $numnew = scalar(keys(%newunique));
+                        my $newputres = &Apache::lonnet::newput('tiny',\%addcourse,$cdom,$cnum);
+                        unless ($newputres eq 'ok') {
+                            push(@errors,&mt('error: could not store course look-up of short URLs'));
+                        }
+                    } else {
+                        push(@errors,&mt('error: could not store unique six character URLs'));
+                    }
+                }
+                my $dellockres = &Apache::lonnet::del_dom('tiny',["lock\0$now"],$cdom);
+                unless ($dellockres eq 'ok') {
+                    push(@errors,&mt('error: could not release lockfile'));
+                }
+            } else {
+                push(@errors,&mt('error: could not obtain lockfile'));
+            }
+            if (keys(%courseonly)) {
+                my $result = &Apache::lonnet::newput('tiny',\%courseonly,$cdom,$cnum);
+                if ($result ne 'ok') {
+                    push(@errors,&mt('error: could not update course look-up of short URLs'));
+                }
+            }
+        }
+    }
+    return ($numnew,\@errors);
+}
+
+sub shorten_symbs {
+    my ($cdom,$init,$su,$coursetiny,$tocreate,$newunique,$addcourse,$courseonly,$failed) = @_;
+    return unless ((ref($su)) && (ref($coursetiny) eq 'HASH') && (ref($tocreate) eq 'HASH') &&
+                   (ref($newunique) eq 'HASH') && (ref($addcourse) eq 'HASH') &&
+                   (ref($courseonly) eq 'HASH') && (ref($failed) eq 'HASH'));
+    my (%possibles,%collisions);
+    foreach my $key (keys(%{$tocreate})) {
+        my $num = String::CRC32::crc32($key);
+        my $tiny = $su->encode($num,$init);
+        if ($tiny) {
+            $possibles{$tiny} = $key;
+        }
+    }
+    if (!$init) {
+        $init = 1;
+    } else {
+        $init ++;
+    }
+    if (keys(%possibles)) {
+        my @posstiny = keys(%possibles);
+        my $configuname = &Apache::lonnet::get_domainconfiguser($cdom);
+        my %currtiny = &Apache::lonnet::get('tiny',\@posstiny,$cdom,$configuname);
+        if (keys(%currtiny)) {
+            foreach my $key (keys(%currtiny)) {
+                next if ($currtiny{$key} eq '');
+                if ($currtiny{$key} eq $possibles{$key}) {
+                    my ($tcnum,$tsymb) = split(/\&/,$currtiny{$key});
+                    unless (($coursetiny->{$tsymb} eq $key) || ($addcourse->{$tsymb} eq $key) || ($courseonly->{$tsymb} eq $key)) {
+                        $courseonly->{$tsymb} = $key;
+                    }
+                } else {
+                    $collisions{$possibles{$key}} = 1;
+                }
+                delete($possibles{$key});
+            }
+        }
+        foreach my $key (keys(%possibles)) {
+            $newunique->{$key} = $possibles{$key};
+            my ($tcnum,$tsymb) = split(/\&/,$possibles{$key});
+            unless (($coursetiny->{$tsymb} eq $key) || ($addcourse->{$tsymb} eq $key) || ($courseonly->{$tsymb} eq $key)) {
+                $addcourse->{$tsymb} = $key;
+            }
+        }
+    }
+    if (keys(%collisions)) {
+        if ($init <5) {
+            if (!$init) {
+                $init = 1;
+            } else {
+                $init ++;
+            }
+            $init = &shorten_symbs($cdom,$init,$su,$coursetiny,\%collisions,
+                                   $newunique,$addcourse,$courseonly,$failed);
+        } else {
+            foreach my $key (keys(%collisions)) {
+                $failed->{$key} = 1;
+            }
+        }
+    }
+    return $init;
+}
+
 1;
 __END__;