--- loncom/auth/lonroles.pm	2010/06/18 08:41:37	1.253
+++ loncom/auth/lonroles.pm	2010/07/26 21:52:15	1.254
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # User Roles Screen
 #
-# $Id: lonroles.pm,v 1.253 2010/06/18 08:41:37 bisitz Exp $
+# $Id: lonroles.pm,v 1.254 2010/07/26 21:52:15 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -210,6 +210,7 @@ sub handler {
     my %dcroles = ();
     my $numdc = &check_fordc(\%dcroles,$then);
     &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'});
+    my $loncaparev = $Apache::lonnet::perlvar{'lonVersion'}; 
 
 # ================================================================== Roles Init
     if ($env{'form.selectrole'}) {
@@ -691,7 +692,7 @@ ENDHEADER
     my (%roletext,%sortrole,%roleclass,%futureroles,%timezones);
     my ($countactive,$countfuture,$inrole,$possiblerole) = 
         &gather_roles($then,$refresh,$now,$reinit,$nochoose,\%roletext,\%sortrole,\%roleclass,
-                      \%futureroles,\%timezones);
+                      \%futureroles,\%timezones,$loncaparev);
 
     $refresh = $now;
     &Apache::lonnet::appenv({'user.refresh.time'  => $refresh});
@@ -873,13 +874,15 @@ ENDHEADER
 }
 
 sub gather_roles {
-    my ($then,$refresh,$now,$reinit,$nochoose,$roletext,$sortrole,$roleclass,$futureroles,$timezones) = @_;
+    my ($then,$refresh,$now,$reinit,$nochoose,$roletext,$sortrole,$roleclass,$futureroles,$timezones,$loncaparev) = @_;
     my ($countactive,$countfuture,$inrole,$possiblerole) = (0,0,0,'');
     my $advanced = $env{'user.adv'};
     my $tryagain = $env{'form.tryagain'};
+    my @ids = &Apache::lonnet::current_machine_ids();
     foreach my $envkey (sort(keys(%env))) {
         my $button = 1;
         my $switchserver='';
+        my $switchwarning;
         my ($role_text,$role_text_end,$sortkey);
         if ($envkey=~/^user\.role\./) {
             my ($role,$where,$trolecode,$tstart,$tend,$tremark,$tstatus,$tpstart,$tpend);
@@ -940,7 +943,6 @@ sub gather_roles {
                 if (($role eq 'ca') || ($role eq 'aa')) {
                     my $home = &Apache::lonnet::homeserver($trest,$tdom);
                     my $allowed=0;
-                    my @ids=&Apache::lonnet::current_machine_ids();
                     foreach my $id (@ids) { if ($id eq $home) { $allowed=1; } }
                     if (!$allowed) {
                         $button=0;
@@ -960,7 +962,6 @@ sub gather_roles {
                     my $home = &Apache::lonnet::homeserver
                         ($env{'user.name'},$env{'user.domain'});
                     my $allowed=0;
-                    my @ids=&Apache::lonnet::current_machine_ids();
                     foreach my $id (@ids) { if ($id eq $home) { $allowed=1; } }
                     if (!$allowed) {
                         $button=0;
@@ -979,6 +980,7 @@ sub gather_roles {
                     $ttype = &Apache::loncommon::course_type($tcourseid);
                     $trole = &Apache::lonnet::plaintext($role,$ttype,$tcourseid);
                     if ($env{'course.'.$tcourseid.'.description'}) {
+                        my $home=$env{'course.'.$tcourseid.'.home'};
                         $twhere=$env{'course.'.$tcourseid.'.description'};
                         $sortkey=$role."\0".$tdom."\0".$twhere."\0".$envkey;
                         $twhere = &HTML::Entities::encode($twhere,'"<>&');
@@ -986,6 +988,13 @@ sub gather_roles {
                             $twhere.=' <span class="LC_fontsize_small">'.
         &Apache::loncommon::syllabuswrapper(&mt('Syllabus'),$trest,$tdom).
                                     '</span>';
+                            unless ($home && grep(/^\Q$home\E$/,@ids) && $loncaparev eq '') {
+                                ($switchserver,$switchwarning) = 
+                                    &check_release_required($loncaparev,$tcourseid,$trolecode);
+                                if ($switchserver || $switchwarning) {
+                                    $button = 0;
+                                }
+                            }
                         }
                     } else {
                         my %newhash=&Apache::lonnet::coursedescription($tcourseid);
@@ -998,6 +1007,14 @@ sub gather_roles {
                                     '</span>';
                             $ttype = $newhash{'type'};
                             $trole = &Apache::lonnet::plaintext($role,$ttype,$tcourseid);
+                            my $home = $newhash{'home'};
+                            unless ($home && grep(/^\Q$home\E$/,@ids) && $loncaparev eq '') {
+                                ($switchserver,$switchwarning) =
+                                    &check_release_required($loncaparev,$tcourseid,$trolecode);
+                                if ($switchserver || $switchwarning) {
+                                    $button = 0;
+                                }
+                            }
                         } else {
                             $twhere=&mt('Currently not available');
                             $env{'course.'.$tcourseid.'.description'}=$twhere;
@@ -1021,7 +1038,7 @@ sub gather_roles {
                 ($role_text,$role_text_end) =
                     &build_roletext($trolecode,$tdom,$trest,$tstatus,$tryagain,
                                     $advanced,$tremark,$tbg,$trole,$twhere,$tpstart,
-                                    $tpend,$nochoose,$button,$switchserver,$reinit);
+                                    $tpend,$nochoose,$button,$switchserver,$reinit,$switchwarning);
                 $roletext->{$envkey}=[$role_text,$role_text_end];
                 if (!$sortkey) {$sortkey=$twhere."\0".$envkey;}
                 $sortrole->{$sortkey}=$envkey;
@@ -1293,7 +1310,7 @@ sub privileges_info {
 }
 
 sub build_roletext {
-    my ($trolecode,$tdom,$trest,$tstatus,$tryagain,$advanced,$tremark,$tbg,$trole,$twhere,$tpstart,$tpend,$nochoose,$button,$switchserver,$reinit) = @_;
+    my ($trolecode,$tdom,$trest,$tstatus,$tryagain,$advanced,$tremark,$tbg,$trole,$twhere,$tpstart,$tpend,$nochoose,$button,$switchserver,$reinit,$switchwarning) = @_;
     my ($roletext,$roletext_end);
     my $is_dc=($trolecode =~ m/^dc\./);
     my $rowspan=($is_dc) ? ''
@@ -1311,6 +1328,7 @@ sub build_roletext {
             } else {
                 $roletext.=('<td'.$rowspan.' class="'.$tbg.'">&nbsp;</td>');
             }
+            $tremark .= $switchwarning;
         } elsif ($tstatus eq 'is') {
             $roletext.='<td'.$rowspan.' class="'.$tbg.'">'.
                         '<input name="'.$buttonname.'" type="button" value="'.
@@ -1491,6 +1509,58 @@ sub check_forcc {
     return $is_cc;
 }
 
+sub check_release_required {
+    my ($loncaparev,$tcourseid,$trolecode) = @_;
+    my ($switchserver,$warning);
+    if ($env{'course.'.$tcourseid.'.internal.releaserequired'} ne '') {
+        my ($reqdmajor,$reqdminor) = ($env{'course.'.$tcourseid.'.internal.releaserequired'} =~ /^(\d+)\.(\d+)$/);
+        my ($major,$minor) = ($loncaparev =~ /^\'?(\d+)\.(\d+)\.[\d.\-]+\'?$/);
+        if ($reqdmajor ne '' && $reqdminor ne '') {
+            my $otherserver;
+            if (($major eq '' && $minor eq '') || 
+                (($reqdmajor > $major) || (($reqdmajor == $major) && ($reqdminor > $minor)))) {
+                my ($userdomserver) = &Apache::lonnet::choose_server($env{'user.domain'});
+                my $switchlcrev = 
+                    &Apache::lonnet::get_server_loncaparev($env{'user.domain'},
+                                                           $userdomserver);
+                my ($swmajor,$swminor) = ($switchlcrev =~ /^\'?(\d+)\.(\d+)\.[\d.\-]+\'?$/);
+                if (($swmajor eq '' && $swminor eq '') || ($reqdmajor > $swmajor) || 
+                    (($reqdmajor == $swmajor) && ($reqdminor > $swminor))) {
+                    my $cdom = $env{'course.'.$tcourseid.'.domain'};
+                    if ($cdom ne $env{'user.domain'}) {
+                        my ($coursedomserver,$coursehostname) = &Apache::lonnet::choose_server($cdom); 
+                        my $serverhomeID = &Apache::lonnet::get_server_homeID($coursehostname);
+                        my $serverhomedom = &Apache::lonnet::host_domain($serverhomeID);
+                        my %defdomdefaults = &Apache::lonnet::get_domain_defaults($serverhomedom);
+                        my %udomdefaults = &Apache::lonnet::get_domain_defaults($env{'user.domain'});
+                        my $remoterev = &Apache::lonnet::get_server_loncaparev($serverhomedom,$coursedomserver);
+                        my $canhost =
+                            &Apache::lonnet::can_host_session($env{'user.domain'},
+                                                              $coursedomserver,
+                                                              $remoterev,
+                                                              $udomdefaults{'remotesessions'},
+                                                              $defdomdefaults{'hostedsessions'});
+
+                        if ($canhost) {
+                            $otherserver = $coursedomserver;
+                        } else {
+                            $warning = &mt('Requires LON-CAPA version [_1].',$env{'course.'.$tcourseid.'.internal.releaserequired'}).'<br />'. &mt("No suitable server could be found amongst servers in either your own domain or in the course's domain.");
+                        }
+                    } else {
+                        $warning = &mt('Requires LON-CAPA version [_1].',$env{'course.'.$tcourseid.'.internal.releaserequired'}).'<br />'.&mt("No suitable server could be found amongst servers in your own domain (which is also the course's domain).");
+                    }
+                } else {
+                    $otherserver = $userdomserver;
+                }
+            }
+            if ($otherserver ne '') {
+                $switchserver = 'otherserver='.$otherserver.'&amp;role='.$trolecode;
+            }
+        }
+    }
+    return ($switchserver,$warning);
+}
+
 sub courselink {
     my ($dcdom,$rowtype) = @_;
     my $courseform=&Apache::loncommon::selectcourse_link