--- loncom/interface/loncoursedata.pm	2002/07/17 12:38:25	1.2
+++ loncom/interface/loncoursedata.pm	2002/07/22 20:35:05	1.3
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # (Publication Handler
 #
-# $Id: loncoursedata.pm,v 1.2 2002/07/17 12:38:25 stredwic Exp $
+# $Id: loncoursedata.pm,v 1.3 2002/07/22 20:35:05 stredwic Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -70,7 +70,7 @@ here in the future.
 
 =pod
 
-=item &DownloadNamePIDSection()
+=item &DownloadClasslist()
 
 Collects lastname, generation, middlename, firstname, PID, and section for each
 student from their environment database.  The list of students is built from
@@ -101,12 +101,23 @@ middlename, and PID : Key is $name.'stud
 
 =cut
 
-sub DownloadStudentNamePIDSection {
-    my ($courseID, $c)=@_;
+sub DownloadClasslist {
+    my ($courseID, $lastDownloadTime, $c)=@_;
     my ($courseDomain,$courseNumber)=split(/\_/,$courseID);
+    my %classlist;
 
-    my %classlist=&Apache::lonnet::dump('classlist',$courseDomain,
-                                        $courseNumber);
+    my $modifiedTime = &GetFileTimestamp($courseDomain, $courseNumber,
+                                     'classlist.db', 
+                                     $Apache::lonnet::perlvar{'lonUsersDir'});
+
+    if($lastDownloadTime ne 'Not downloaded' &&
+       $lastDownloadTime >= $modifiedTime && $modifiedTime >= 0) {
+        $classlist{'lastDownloadTime'}=time;
+        $classlist{'UpToDate'} = 'true';
+        return \%classlist;
+    }
+
+    %classlist=&Apache::lonnet::dump('classlist',$courseDomain, $courseNumber);
     my ($checkForError)=keys (%classlist);
     if($checkForError =~ /^(con_lost|error|no_such_host)/i) {
         return \%classlist;
@@ -135,9 +146,12 @@ sub DownloadStudentNamePIDSection {
 
         #Section
         my %section=&Apache::lonnet::dump('roles',$studentDomain,$studentName);
-        $classlist{$name.':section'}=\%section;
+        $classlist{$name.':sections'}=\%section;
     }
 
+    $classlist{'UpToDate'} = 'false';
+    $classlist{'lastDownloadTime'}=time;
+
     return \%classlist;
 }
 
@@ -146,7 +160,9 @@ sub DownloadStudentNamePIDSection {
 =item &DownloadStudentCourseInformation()
 
 Dump of all the course information for a single student.  There is no
-pruning of data, it is all stored in a hash and returned.
+pruning of data, it is all stored in a hash and returned.  It also
+checks the timestamp of the students course database file and only downloads
+if it has been modified since the last download.
 
 =over 4
 
@@ -166,12 +182,23 @@ database.
 =cut
 
 sub DownloadStudentCourseInformation {
-    my ($name,$courseID)=@_;
+    my ($name,$courseID,$lastDownloadTime)=@_;
+    my %courseData;
     my ($studentName,$studentDomain) = split(/\:/,$name);
 
+    my $modifiedTime = &GetFileTimestamp($studentDomain, $studentName,
+                                      $courseID.'.db', 
+                                      $Apache::lonnet::perlvar{'lonUsersDir'});
+    if($lastDownloadTime >= $modifiedTime) {
+        $courseData{'lastDownloadTime'}=time;
+        $courseData{'UpToDate'} = 'true';
+        return \%courseData;
+    }
+
     # Download student course data
-    my %courseData=&Apache::lonnet::dump($courseID,$studentDomain,
-					 $studentName);
+    %courseData=&Apache::lonnet::dump($courseID, $studentDomain, $studentName);
+    $courseData{'UpToDate'} = 'false';
+    $courseData{'lastDownloadTime'}=time;
     return \%courseData;
 }
 
@@ -447,7 +474,6 @@ chart.
 
 =back
 
-=cut
 
 sub ProcessSection {
     my ($sectionData,$courseid,$ActiveFlag)=@_;
@@ -455,7 +481,7 @@ sub ProcessSection {
     $courseid=~s/^(\w)/\/$1/;
 
     my $cursection='-1';
-    my $oldsection='-1';
+    my $oldend='-1';
     my $status='Expired';
     my $section='';
     foreach my $key (keys (%$sectionData)) {
@@ -485,103 +511,33 @@ sub ProcessSection {
                 last;
             }
             if($notactive == 1) {
-                $oldsection=$section;
+                if($end > $oldend) {
+                    $cursection=$section;
+                    $oldend = $end;
+                }
             }
 	}
     }
-    if($status eq $ActiveFlag) {
-        if($cursection eq '-1') {
-            return $oldsection;
-        }
-        return $cursection;
-    }
-    if($ActiveFlag eq 'Any') {
-        if($cursection eq '-1') {
-            return $oldsection;
-        }
-        return $cursection;
-    }
-    return '-1';
-}
-
-=pod
-
-=item &ProcessNamePIDSection()
-
-Takes data downloaded for a student and breaks it up into managable pieces and 
-stored in cache data.  The username, domain, class related date, PID, 
-full name, and section are all processed here.
-
-=over 4
-
-Input: $cache, $studentInformation, $section, $date, $name, $courseID
 
-$cache:  A hash pointer to store the data
-
-$studentInformation:  Student information is what was requested in 
-&DownloadPrerequistedData().  See that function for what data is requested.
-
-$section: A hash pointer to class section related information.
-
-$date:  A composite of the start and end date for this class for this
-student.  Format:  end:start
-
-$name:  the username:domain information
-
-$courseID: The course ID
-
-Output: None
-
-*NOTE:  There is no return value, but if an error occurs a key is added to 
-the cache data with the value being the error message.  The key is 
-username:domain:error.  It will only exist if an error occurs.
-
-=back
+    return ($cursections, $status);
+}
 
 =cut
 
-sub ProcessStudentNamePIDSection {
-    my ($cache,$studentInformation,$section,$date,$name,$courseID,$status)=@_;
-    my ($studentName,$studentDomain) = split(/\:/,$name);
-
-    $cache->{$name.':username'}=$studentName;
-    $cache->{$name.':domain'}=$studentDomain;
-    $cache->{$name.':date'}=$date;
-
-    my ($checkForError)=keys(%$studentInformation);
-    if($checkForError =~ /^(con_lost|error|no_such_host)/i) {
-	$cache->{$name.':error'}=
-	    'Could not download student environment data.';
-	$cache->{$name.':fullname'}='';
-	$cache->{$name.':id'}='';
-    } else {
-	$cache->{$name.':fullname'}=&ProcessFullName(
-                                          $studentInformation->{'lastname'},
-				          $studentInformation->{'generation'},
-				          $studentInformation->{'firstname'},
-                                          $studentInformation->{'middlename'});
-	$cache->{$name.':id'}=$studentInformation->{'id'};
-    }
-
-    my $sec=&ProcessSection($section, $courseID, $status);
-    if($sec != -1) {
-        $cache->{$name.':section'}=$sec;
-    } else {
-        $cache->{$name.':section'}='';
-    }
-
-    return;
-}
-
 =pod
 
-=item &ProcessClassList()
+=item &ProcessClasslist()
 
-Taking the class list dumped from &DownloadPrerequisiteData(), all the 
+Taking the class list dumped from &DownloadClasslist(), all the 
 students and their non-class information is processed using the 
 &ProcessStudentInformation() function.  A date stamp is also recorded for
 when the data was processed.
 
+Takes data downloaded for a student and breaks it up into managable pieces and 
+stored in cache data.  The username, domain, class related date, PID, 
+full name, and section are all processed here.
+
+
 =over 4
 
 Input: $cache, $classlist, $courseID, $ChartDB, $c
@@ -589,7 +545,7 @@ Input: $cache, $classlist, $courseID, $C
 $cache: A hash pointer to store the data
 
 $classlist:  The hash of data collected about a student from 
-&DownloadPrerequisteData().  The hash contains a list of students, a pointer 
+&DownloadClasslist().  The hash contains a list of students, a pointer 
 to a hash of student information for each student, and each student's section 
 number.
 
@@ -609,28 +565,80 @@ be considered in an arbitrary order.
 
 =cut
 
-sub ProcessClassList {
-    my ($cache,$classlist,$courseID,$status,$c)=@_;
+sub ProcessClasslist {
+    my ($cache,$classlist,$courseID,$c)=@_;
     my @names=();
 
+    $cache->{'ClasslistTimeStamp'}=$classlist->{'lastDownloadTime'};
+    if($classlist->{'UpToDate'} eq 'true') {
+        return split(/:::/,$cache->{'NamesOfStudents'});;
+    }
+
     foreach my $name (keys(%$classlist)) {
         if($name =~ /\:section/ || $name =~ /\:studentInformation/ ||
-           $name eq '') {
+           $name eq '' || $name eq 'UpToDate' || $name eq 'lastDownloadTime') {
             next;
         }
         if($c->aborted()) {
-            last;
+            return ();
         }
         push(@names,$name);
-        &ProcessStudentNamePIDSection($cache,
-                                     $classlist->{$name.':studentInformation'},
-                                     $classlist->{$name.':section'},
-                                     $classlist->{$name},
-                                     $name,$courseID,$status);
+        my $studentInformation = $classlist->{$name.':studentInformation'},
+        my $sectionData = $classlist->{$name.':sections'},
+        my $date = $classlist->{$name},
+        my ($studentName,$studentDomain) = split(/\:/,$name);
+
+        $cache->{$name.':username'}=$studentName;
+        $cache->{$name.':domain'}=$studentDomain;
+        if(!defined($cache->{$name.':lastDownloadTime'})) {
+            $cache->{$name.':lastDownloadTime'}='Not downloaded';
+        }
+
+        my ($checkForError)=keys(%$studentInformation);
+        if($checkForError =~ /^(con_lost|error|no_such_host)/i) {
+            $cache->{$name.':error'}=
+                'Could not download student environment data.';
+            $cache->{$name.':fullname'}='';
+            $cache->{$name.':id'}='';
+        } else {
+            $cache->{$name.':fullname'}=&ProcessFullName(
+                                          $studentInformation->{'lastname'},
+                                          $studentInformation->{'generation'},
+                                          $studentInformation->{'firstname'},
+                                          $studentInformation->{'middlename'});
+            $cache->{$name.':id'}=$studentInformation->{'id'};
+        }
+
+        my ($end, $start)=split(':',$date);
+        $courseID=~s/\_/\//g;
+        $courseID=~s/^(\w)/\/$1/;
+
+        my $sec='';
+        foreach my $key (keys (%$sectionData)) {
+            my $value = $sectionData->{$key};
+            if ($key=~/^$courseID(?:\/)*(\w+)*\_st$/) {
+                my $tempsection=$1;
+                if($key eq $courseID.'_st') {
+                    $tempsection='';
+                }
+                my ($dummy,$roleend,$rolestart)=split(/\_/,$value);
+                if($roleend eq $end && $rolestart eq $start) {
+                    $sec = $tempsection;
+                    last;
+                }
+            }
+        }
+
+        my $status='Expired';
+        if(((!$end) || time < $end) && ((!$start) || (time > $start))) {
+            $status='Active';
+        }
+        $cache->{$name.':Status'}=$status;
+        $cache->{$name.':section'}=$sec;
     }
 
-    # Time of download
-    $cache->{'time'}=localtime();
+    $cache->{'ClasslistTimestamp'}=time;
+    $cache->{'NamesOfStudents'}=join(':::',@names);
 
     return @names;
 }
@@ -671,20 +679,25 @@ will only exist if an error occured.  Th
 sub ProcessStudentData {
     my ($cache,$courseData,$name)=@_;
 
-    my ($checkForError) = keys(%$courseData);
-    if($checkForError =~ /^(con_lost|error|no_such_host)/i) {
-        $cache->{$name.':error'}='Could not download course data.';
-    } else {
-        foreach my $key (keys (%$courseData)) {
-            $cache->{$name.':'.$key}=$courseData->{$key};
-        }
-        if(defined($cache->{'NamesOfStudents'})) {
-            $cache->{'NamesOfStudents'}.=':::'.$name;
-        } else {
-            $cache->{'NamesOfStudents'}=$name;
+    if($courseData->{'UpToDate'} eq 'true') {
+        $cache->{$name.':lastDownloadTime'}=$courseData->{'lastDownloadTime'};
+        return;
+    }
+
+    my @courseKeys = keys(%$courseData);
+
+    foreach (@courseKeys) {
+        if(/^(con_lost|error|no_such_host)/i) {
+            $cache->{$name.':error'}='Could not download course data.';
+            return;
         }
     }
 
+    $cache->{$name.':lastDownloadTime'}=$courseData->{'lastDownloadTime'};
+    foreach (@courseKeys) {
+        $cache->{$name.':'.$_}=$courseData->{$_};
+    }
+
     return;
 }
 
@@ -815,34 +828,24 @@ sub TestCacheData {
     return $isCached;
 }
 
-#sub CheckStatus {
-#    my ($name, $data, $status)=@_;
-
-#    if($status eq 'Any') {
-#        my $section = ' ';
-#        foreach (split(':',$data->{$name.':Sections'})) {
-#            if($data->{$name.':'.$_.'Status'} eq 'Active') {
-#                return $_;
-#            }
-#            $section = $_;
-#        }
-#        return $_;
-#    }
-
-#    foreach (split(':',$data->{$name.':Sections'})) {
-#        if($data->{$name.':'.$_.'Status'} eq $status) {
-#            return $_;
-#        }
-#    }
-
-#    foreach (split(':',$data->{$name.':Sections'})) {
-#        if($data->{$name.':'.$_.'Status'} eq 'Any') {
-#            return $_;
-#        }
-#    }
-
-#    return 'not found';
-#}
+sub GetFileTimestamp {
+    my ($studentDomain,$studentName,$filename,$root)=@_;
+    $studentDomain=~s/\W//g;
+    $studentName=~s/\W//g;
+    my $subdir=$studentName.'__';
+    $subdir =~ s/(.)(.)(.).*/$1\/$2\/$3/;
+    my $proname="$studentDomain/$subdir/$studentName";
+    $proname .= '/'.$filename;
+    my @dir = &Apache::lonnet::dirlist($proname, $studentDomain, $studentName,
+                                       $root);
+    my $fileStat = $dir[0];
+    my @stats = split('&', $fileStat);
+    if(@stats) {
+        return $stats[9];
+    } else {
+        return -1;
+    }
+}
 
 # ----- END HELPER FUNCTIONS --------------------------------------------