--- loncom/interface/loncoursegroups.pm	2006/11/28 19:46:00	1.65
+++ loncom/interface/loncoursegroups.pm	2006/12/04 21:44:02	1.68
@@ -1,6 +1,6 @@
 # The LearningOnline Network with CAPA
 #
-# $Id: loncoursegroups.pm,v 1.65 2006/11/28 19:46:00 raeburn Exp $
+# $Id: loncoursegroups.pm,v 1.68 2006/12/04 21:44:02 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -1297,10 +1297,14 @@ sub verify_reenable {
 }
 
 sub reenable_group {
-    my ($r,$cdom,$cnum,$groupname,) = @_;
+    my ($r,$cdom,$cnum,$groupname) = @_;
     my %groups = 
         &Apache::longroup::coursegroups($cdom,$cnum,$groupname,
                                         'deleted_groups');
+    if (keys(%groups) == 0) {
+        $r->print(&mt('The group ([_1]) was not re-enabled, because it is not a deleted group.<br />Perhaps it has already been re-enabled?',$groupname));
+        return;
+    }
     my %groupinfo = 
         &Apache::longroup::get_group_settings($groups{$groupname});
     my $defstart = $groupinfo{'startdate'};
@@ -1368,6 +1372,7 @@ sub reenable_group {
     } else {
         $r->print(&mt('Re-enabling group failed'));
     }
+    return;
 }
 
 sub header {
@@ -3134,7 +3139,7 @@ sub write_group_data {
                                            $description,$tools,\%groupinfo,
                                            $gpterm,$ucgpterm,$crstype);
             if ($result ne 'ok') {
-                $r->print(&mt('A problem occurred when creating folders for the new [_1]. [_2].<br />',$gpterm,$result));
+                $r->print(&mt('A problem occurred when creating folders for the new [_1].<br />[_2]<br />',$gpterm,$result));
             }
             $r->print(&mt('[_1] [_2] was created.<br />',$ucgpterm,$groupname));
         } elsif ($action eq 'modify') {
@@ -3668,28 +3673,38 @@ sub add_group_folder {
     if ($cdom eq '' || $cnum eq '') {
         return &mt('Error: invalid course domain or number - group folder creation failed');  
     }
-    my ($outcome,$allgrpsmap,$grpmap,$boardsmap,$grppage);
-    my $navmap = Apache::lonnavmaps::navmap->new();
+    my ($outcome,$allgrpsmap,$grpmap,$boardsmap,$grppage,$warning);
     my $crspath = '/uploaded/'.$cdom.'/'.$cnum.'/';
     $allgrpsmap = $crspath.'group_allfolders.sequence';
-    my $topmap = $navmap->getResourceByUrl($allgrpsmap);
-    undef($navmap);
     if ($action eq 'create') {
-    # check if group_allfolders.sequence exists.
-        if (!$topmap) {
-            my $grpstitle = &mt('[_1] [_2]s',$crstype,$ucgpterm);
-            my $topmap_url = '/'.$env{'course.'.$env{'request.course.id'}.'.url'};
-            $topmap_url =~ s|/+|/|g;
-            if ($topmap_url =~ m|^/uploaded|) {
-                $outcome = &map_updater($cdom,$cnum,'group_allfolders.sequence',
-                                        'toplevelgroup',$grpstitle,$topmap_url);
+        if (&get_folder_lock($cdom,$cnum,'group_allfolders',$now) eq 'ok') {
+            # check if group_allfolders.sequence exists.
+            my ($errtext,$fatal)=&LONCAPA::map::mapread($allgrpsmap);
+            if ($fatal == 2) { #file does not exist;
+                my $grpstitle = &mt('[_1] [_2]s',$crstype,$ucgpterm);
+                my $topmap_url = '/'.$env{'course.'.$env{'request.course.id'}.'.url'};
+                $topmap_url =~ s|/+|/|g;
+                if ($topmap_url =~ m|^/uploaded|) {
+                    $outcome = &map_updater($cdom,$cnum,'group_allfolders.sequence',
+                                            'toplevelgroup',$grpstitle,$topmap_url);
+                } else {
+                    $outcome = &mt('Non-standard course - folder for all groups not added.');
+                }
                 if ($outcome ne 'ok') {
+                    my $delresult = &release_folder_lock($cdom,$cnum,'group_allfolders');
+                    if ($delresult ne 'ok') {
+                        $warning = $delresult;
+                    }
                     return $outcome;
                 }
-            } else {
-                $outcome = &mt('Non-standard course - folder for all groups not added.');
-                return $outcome;
             }
+            my $delresult = &release_folder_lock($cdom,$cnum,'group_allfolders');
+            if ($delresult ne 'ok') {
+                $warning = $delresult ;
+            }
+        } else {
+            $outcome = &mt('Could not obtain exclusive lock to check status of the folder for all groups. No group folder added.');
+            return $outcome;
         }
         my $grpfolder = &mt('[_1] Folder -',$ucgpterm,).$description;
         $grppage='/adm/'.$cdom.'/'.$cnum.'/'.$groupname.'/smppg';
@@ -3699,7 +3714,7 @@ sub add_group_folder {
                                    'grpseq',$grpfolder,$allgrpsmap,$grppage,
                                    $grptitle);
         if ($outcome ne 'ok') {
-            return $outcome;
+            return $outcome.$warning;
         }
         my $pageout = &create_homepage($cdom,$cnum,$groupname,$groupinfo,
                                        $tools,$gpterm,$ucgpterm,$now);
@@ -3710,7 +3725,7 @@ sub add_group_folder {
             my $outcome = &map_updater($cdom,$cnum,'group_boards_'.$groupname.
                                        '.sequence','bbseq',$disctitle,$grpmap);
             if ($outcome ne 'ok') {
-                return $outcome;
+                return $outcome.$warning;
             }
             $boardsmap = $crspath.'group_boards_'.$groupname.'.sequence';
         }
@@ -3718,7 +3733,7 @@ sub add_group_folder {
         #modify group folder if status of discussions tools is changed
     }
     my ($furl,$ferr)= &Apache::lonuserstate::readmap($cdom.'/'.$cnum);
-    $navmap = Apache::lonnavmaps::navmap->new();
+    my $navmap = Apache::lonnavmaps::navmap->new();
     # modify parameters
     my $parm_result;
     if ($action eq 'create') {
@@ -3732,8 +3747,39 @@ sub add_group_folder {
             $parm_result .= &parm_setter($navmap,$cdom,$boardsmap,$groupname);
         }
     }
+    undef($navmap);
     if ($parm_result) {
-        return $parm_result;
+        return $warning.$parm_result;
+    } else {
+        return 'ok';
+    }
+}
+
+sub get_folder_lock {
+    my ($cdom,$cnum,$folder_name,$now) = @_;  
+    # get lock for folder being edited.
+    my $lockhash = {
+                  $folder_name."\0".'locked_folder' => $now.':'.$env{'user.name'}.
+                                                     ':'.$env{'user.domain'},
+                   };
+    my $tries = 0;
+    my $gotlock = &Apache::lonnet::newput('coursegroups',$lockhash,$cdom,$cnum);
+
+    while (($gotlock ne 'ok') && $tries <3) {
+        $tries ++;
+        sleep(1);
+        $gotlock = &Apache::lonnet::newput('coursegroups',$lockhash,$cdom,$cnum);
+    }
+    return $gotlock;
+}
+
+sub release_folder_lock {
+    my ($cdom,$cnum,$folder_name) = @_;  
+    #  remove lock
+    my @del_lock = ($folder_name."\0".'locked_folder');
+    my $dellockoutcome=&Apache::lonnet::del('coursegroups',\@del_lock,$cdom,$cnum);
+    if ($dellockoutcome ne 'ok') {
+        return ('<br />'.&mt('Warning: failed to release lock for folder: [_1].',$folder_name).'<br />'); 
     } else {
         return 'ok';
     }
@@ -3750,7 +3796,7 @@ sub map_updater {
     if ($newmapurl !~ m|^/uploaded|) {
         $outcome = &mt('Error uploading new folder.')." ($newfile): $newmapurl".'<br />';
         return $outcome;
-    } 
+    }
     my ($errtext,$fatal)=&LONCAPA::map::mapread($parentmap);
     if ($fatal) {
         $outcome = &mt('Error reading contents of parent folder')." ($parentmap): $errtext".'<br />';
@@ -3761,7 +3807,7 @@ sub map_updater {
                                                  ':false:normal:res';
         $LONCAPA::map::order[1+$#LONCAPA::map::order]=$newidx;
         my ($outtext,$errtext) = &LONCAPA::map::storemap($parentmap,1);
-        if ($outtext) {
+        if ($errtext) {
             $outcome = &mt('Error storing updated parent folder')." ($parentmap):  $errtext".'<br />';
             return $outcome;
         }
@@ -3796,18 +3842,23 @@ sub parm_setter {
                                         },
                         );
     my $res = $navmap->getResourceByUrl($url);
-    my $symb = $res->symb();
-    foreach my $level (keys(%hide_settings)) {
-        my $parmresult =  &Apache::lonparmset::storeparm_by_symb($symb,
+    if ($res) {
+        my $symb = $res->symb();
+        foreach my $level (keys(%hide_settings)) {
+            my $parmresult =  
+                       &Apache::lonparmset::storeparm_by_symb($symb,
                                                  '0_hiddenresource',
                                                  $hide_settings{$level}{'num'},
                                                  $hide_settings{$level}{'set'},
                                                  'string_yesno',undef,$cdom,
                                                  undef,undef,
                                                  $hide_settings{$level}{'extra'});
-        if ($parmresult) {
-            $allresults .= $level.': '.$parmresult;
+            if ($parmresult) {
+                $allresults .= $level.': '.$parmresult;
+            }
         }
+    } else {
+        $allresults = &mt('Parameters not set for [_1] because the resource was not recognized as part of the course',$url).'<br />';
     }
     return $allresults;
 }