Diff for /loncom/interface/lonnavmaps.pm between versions 1.64 and 1.222

version 1.64, 2002/10/04 15:35:26 version 1.222, 2003/08/19 15:29:33
Line 36 Line 36
 # 3/1/1,6/1,17/1,29/1,30/1,2/8,9/21,9/24,9/25 Gerd Kortemeyer  # 3/1/1,6/1,17/1,29/1,30/1,2/8,9/21,9/24,9/25 Gerd Kortemeyer
 # YEAR=2002  # YEAR=2002
 # 1/1 Gerd Kortemeyer  # 1/1 Gerd Kortemeyer
 #  # Oct-Nov Jeremy Bowers
   # YEAR=2003
   # Jeremy Bowers ... lots of days
   
 package Apache::lonnavmaps;  package Apache::lonnavmaps;
   
 use strict;  use strict;
 use Apache::Constants qw(:common :http);  use Apache::Constants qw(:common :http);
 use Apache::lonnet();  
 use Apache::loncommon();  use Apache::loncommon();
 use HTML::TokeParser;  use Apache::lonmenu();
 use GDBM_File;  use POSIX qw (floor strftime);
   use Data::Dumper; # for debugging, not always used
   
   # symbolic constants
   sub SYMB { return 1; }
   sub URL { return 2; }
   sub NOTHING { return 3; }
   
   # Some data
   
   my $resObj = "Apache::lonnavmaps::resource";
   
   # Keep these mappings in sync with lonquickgrades, which uses the colors
   # instead of the icons.
   my %statusIconMap = 
       ( $resObj->NETWORK_FAILURE    => '',
         $resObj->NOTHING_SET        => '',
         $resObj->CORRECT            => 'navmap.correct.gif',
         $resObj->EXCUSED            => 'navmap.correct.gif',
         $resObj->PAST_DUE_NO_ANSWER => 'navmap.wrong.gif',
         $resObj->PAST_DUE_ANSWER_LATER => 'navmap.wrong.gif',
         $resObj->ANSWER_OPEN        => 'navmap.wrong.gif',
         $resObj->OPEN_LATER         => '',
         $resObj->TRIES_LEFT         => 'navmap.open.gif',
         $resObj->INCORRECT          => 'navmap.wrong.gif',
         $resObj->OPEN               => 'navmap.open.gif',
         $resObj->ATTEMPTED          => 'navmap.ellipsis.gif',
         $resObj->ANSWER_SUBMITTED   => 'navmap.ellipsis.gif' );
   
   my %iconAltTags = 
       ( 'navmap.correct.gif' => 'Correct',
         'navmap.wrong.gif'   => 'Incorrect',
         'navmap.open.gif'    => 'Open' );
   
   # Defines a status->color mapping, null string means don't color
   my %colormap = 
       ( $resObj->NETWORK_FAILURE        => '',
         $resObj->CORRECT                => '',
         $resObj->EXCUSED                => '#3333FF',
         $resObj->PAST_DUE_ANSWER_LATER  => '',
         $resObj->PAST_DUE_NO_ANSWER     => '',
         $resObj->ANSWER_OPEN            => '#006600',
         $resObj->OPEN_LATER             => '',
         $resObj->TRIES_LEFT             => '',
         $resObj->INCORRECT              => '',
         $resObj->OPEN                   => '',
         $resObj->NOTHING_SET            => '',
         $resObj->ATTEMPTED              => '',
         $resObj->ANSWER_SUBMITTED       => ''
         );
   # And a special case in the nav map; what to do when the assignment
   # is not yet done and due in less then 24 hours
   my $hurryUpColor = "#FF0000";
   
 # -------------------------------------------------------------- Module Globals  sub handler {
 my %hash;      my $r = shift;
 my @rows;      real_handler($r);
   }
 #  
 # These cache hashes need to be independent of user, resource and course  
 # (user and course can/should be in the keys)  
 #  
   
 my %courserdatas;  
 my %userrdatas;  
   
 #  
 # These global hashes are dependent on user, course and resource,   
 # and need to be initialized every time when a sheet is calculated  
 #  
 my %courseopt;  
 my %useropt;  
 my %parmhash;  
   
 # This parameter keeps track of whether obtaining the user's information  
 # failed, which the colorizer in astatus can use  
 my $networkFailedFlag = 0;  
   
 # ------------------------------------------------------------------ Euclid gcd  
   
 sub euclid {  
     my ($e,$f)=@_;  
     my $a; my $b; my $r;  
     if ($e>$f) { $b=$e; $r=$f; } else { $r=$e; $b=$f; }  
     while ($r!=0) {  
         $a=$b; $b=$r;  
         $r=$a%$b;  
     }  
     return $b;  
 }  
   
 # --------------------------------------------------------------------- Parmval  
   
 # -------------------------------------------- Figure out a cascading parameter  
 #  
 # For this function to work  
 #  
 # * parmhash needs to be tied  
 # * courseopt and useropt need to be initialized for this user and course  
 #  
   
 sub parmval {  sub real_handler {
     my ($what,$symb)=@_;      my $r = shift;
     my $cid=$ENV{'request.course.id'};  
     my $csec=$ENV{'request.course.sec'};  
     my $uname=$ENV{'user.name'};  
     my $udom=$ENV{'user.domain'};  
   
     unless ($symb) { return ''; }      # Handle header-only request
     my $result='';      if ($r->header_only) {
           if ($ENV{'browser.mathml'}) {
               $r->content_type('text/xml');
           } else {
               $r->content_type('text/html');
           }
           $r->send_http_header;
           return OK;
       }
   
     my ($mapname,$id,$fn)=split(/\_\_\_/,$symb);      # Send header, don't cache this page
       if ($ENV{'browser.mathml'}) {
           $r->content_type('text/xml');
       } else {
           $r->content_type('text/html');
       }
       &Apache::loncommon::no_cache($r);
       $r->send_http_header;
   
 # ----------------------------------------------------- Cascading lookup scheme      # Create the nav map
     my $rwhat=$what;      my $navmap = Apache::lonnavmaps::navmap->new();
     $what=~s/^parameter\_//;  
     $what=~s/\_/\./;  
   
     my $symbparm=$symb.'.'.$what;  
     my $mapparm=$mapname.'___(all).'.$what;  
     my $usercourseprefix=$uname.'_'.$udom.'_'.$cid;  
   
     my $seclevel= $usercourseprefix.'.['.$csec.'].'.$what;      if (!defined($navmap)) {
     my $seclevelr=$usercourseprefix.'.['.$csec.'].'.$symbparm;          my $requrl = $r->uri;
     my $seclevelm=$usercourseprefix.'.['.$csec.'].'.$mapparm;          $ENV{'user.error.msg'} = "$requrl:bre:0:0:Course not initialized";
           return HTTP_NOT_ACCEPTABLE;
       }
   
     my $courselevel= $usercourseprefix.'.'.$what;      $r->print("<html><head>\n");
     my $courselevelr=$usercourseprefix.'.'.$symbparm;      $r->print("<title>Navigate Course Contents</title>");
     my $courselevelm=$usercourseprefix.'.'.$mapparm;  # ------------------------------------------------------------ Get query string
       &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['register']);
       
   # ----------------------------------------------------- Force menu registration
       my $addentries='';
       if ($ENV{'form.register'}) {
          $addentries=' onLoad="'.&Apache::lonmenu::loadevents().
      '" onUnload="'.&Apache::lonmenu::unloadevents().'"';
          $r->print(&Apache::lonmenu::registerurl(1));
       }
   
 # ---------------------------------------------------------- first, check user      # Header
     if (defined($uname)) {      $r->print('</head>'.
         if (defined($useropt{$courselevelr})) { return $useropt{$courselevelr}; }                &Apache::loncommon::bodytag('Navigate Course Contents','',
         if (defined($useropt{$courselevelm})) { return $useropt{$courselevelm}; }                                      $addentries,'','',$ENV{'form.register'}));
         if (defined($useropt{$courselevel})) { return $useropt{$courselevel}; }      $r->print('<script>window.focus();</script>');
   
       $r->rflush();
   
       # Check that it's defined
       if (!($navmap->courseMapDefined())) {
           $r->print('<font size="+2" color="red">Coursemap undefined.</font>' .
                     '</body></html>');
           return OK;
     }      }
   
 # ------------------------------------------------------- second, check course      # See if there's only one map in the top-level, if we don't
     if (defined($csec)) {      # already have a filter... if so, automatically display it
         if (defined($courseopt{$seclevelr})) { return $courseopt{$seclevelr}; }      # (older code; should use retrieveResources)
         if (defined($courseopt{$seclevelm})) { return $courseopt{$seclevelm}; }      if ($ENV{QUERY_STRING} !~ /filter/) {
         if (defined($courseopt{$seclevel})) { return $courseopt{$seclevel}; }          my $iterator = $navmap->getIterator(undef, undef, undef, 0);
           my $curRes;
           my $sequenceCount = 0;
           my $sequenceId;
           while ($curRes = $iterator->next()) {
               if (ref($curRes) && $curRes->is_sequence()) {
                   $sequenceCount++;
                   $sequenceId = $curRes->map_pc();
               }
           }
           
           if ($sequenceCount == 1) {
               # The automatic iterator creation in the render call 
               # will pick this up. We know the condition because
               # the defined($ENV{'form.filter'}) also ensures this
               # is a fresh call.
               $ENV{'form.filter'} = "$sequenceId";
           }
     }      }
   
     if (defined($courseopt{$courselevelr})) { return $courseopt{$courselevelr}; }      my $jumpToFirstHomework = 0;
     if (defined($courseopt{$courselevelm})) { return $courseopt{$courselevelm}; }      # Check to see if the student is jumping to next open, do-able problem
     if (defined($courseopt{$courselevel})) { return $courseopt{$courselevel}; }      if ($ENV{QUERY_STRING} eq 'jumpToFirstHomework') {
           $jumpToFirstHomework = 1;
           # Find the next homework problem that they can do.
           my $iterator = $navmap->getIterator(undef, undef, undef, 1);
           my $curRes;
           my $foundDoableProblem = 0;
           my $problemRes;
           
           while (($curRes = $iterator->next()) && !$foundDoableProblem) {
               if (ref($curRes) && $curRes->is_problem()) {
                   my $status = $curRes->status();
                   if ($curRes->completable()) {
                       $problemRes = $curRes;
                       $foundDoableProblem = 1;
   
 # ----------------------------------------------------- third, check map parms                      # Pop open all previous maps
                       my $stack = $iterator->getStack();
                       pop @$stack; # last resource in the stack is the problem
                                    # itself, which we don't need in the map stack
                       my @mapPcs = map {$_->map_pc()} @$stack;
                       $ENV{'form.filter'} = join(',', @mapPcs);
   
     my $thisparm=$parmhash{$symbparm};                      # Mark as both "here" and "jump"
     if (defined($thisparm)) { return $thisparm; }                      $ENV{'form.postsymb'} = $curRes->symb();
                   }
               }
           }
   
 # ----------------------------------------------------- fourth , check default          # If we found no problems, print a note to that effect.
           if (!$foundDoableProblem) {
               $r->print("<font size='+2'>All homework assignments have been completed.</font><br /><br />");
           }
       } else {
           $r->print("<a href='navmaps?jumpToFirstHomework'>" .
                     "Go To My First Homework Problem</a>&nbsp;&nbsp;&nbsp;&nbsp;");
       }
   
     my $default=&Apache::lonnet::metadata($fn,$rwhat.'.default');      my $suppressEmptySequences = 0;
     if (defined($default)) { return $default}      my $filterFunc = undef;
       my $resource_no_folder_link = 0;
   
       # Display only due homework.
       my $showOnlyHomework = 0;
       if ($ENV{QUERY_STRING} eq 'showOnlyHomework') {
           $showOnlyHomework = 1;
           $suppressEmptySequences = 1;
           $filterFunc = sub { my $res = shift; 
                               return $res->completable() || $res->is_map();
                           };
           $r->print("<p><font size='+2'>Uncompleted Homework</font></p>");
           $ENV{'form.filter'} = '';
           $ENV{'form.condition'} = 1;
    $resource_no_folder_link = 1;
       } else {
           $r->print("<a href='navmaps?showOnlyHomework'>" .
                     "Show Only Uncompleted Homework</a>&nbsp;&nbsp;&nbsp;&nbsp;");
       }
   
 # --------------------------------------------------- fifth , cascade up parts      # renderer call
       my $renderArgs = { 'cols' => [0,1,2,3],
                          'url' => '/adm/navmaps',
                          'navmap' => $navmap,
                          'suppressNavmap' => 1,
                          'suppressEmptySequences' => $suppressEmptySequences,
                          'filterFunc' => $filterFunc,
          'resource_no_folder_link' => $resource_no_folder_link,
                          'r' => $r};
       my $render = render($renderArgs);
       $navmap->untieHashes();
   
     my ($space,@qualifier)=split(/\./,$rwhat);      # If no resources were printed, print a reassuring message so the
     my $qualifier=join('.',@qualifier);      # user knows there was no error.
     unless ($space eq '0') {      if ($renderArgs->{'counter'} == 0) {
         my ($part,$id)=split(/\_/,$space);          if ($showOnlyHomework) {
         if ($id) {              $r->print("<p><font size='+1'>All homework is currently completed.</font></p>");
             my $partgeneral=&parmval($part.".$qualifier",$symb);          } else { # both jumpToFirstHomework and normal use the same: course must be empty
             if (defined($partgeneral)) { return $partgeneral; }              $r->print("<p><font size='+1'>This course is empty.</font></p>");
         } else {  
             my $resourcegeneral=&parmval("0.$qualifier",$symb);  
             if (defined($resourcegeneral)) { return $resourcegeneral; }  
         }          }
     }      }
     return '';  
       $r->print("</body></html>");
       $r->rflush();
   
       return OK;
 }  }
   
   # Convenience functions: Returns a string that adds or subtracts
   # the second argument from the first hash, appropriate for the 
   # query string that determines which folders to recurse on
   sub addToFilter {
       my $hashIn = shift;
       my $addition = shift;
       my %hash = %$hashIn;
       $hash{$addition} = 1;
   
       return join (",", keys(%hash));
   }
   
   sub removeFromFilter {
       my $hashIn = shift;
       my $subtraction = shift;
       my %hash = %$hashIn;
   
 # ------------------------------------------------------------- Find out status      delete $hash{$subtraction};
 # return codes      return join(",", keys(%hash));
 # tcode (timecode)  }
 # 1: will open later  
 # 2: is open and not past due yet  # Convenience function: Given a stack returned from getStack on the iterator,
 # 3: is past due date  # return the correct src() value.
 # 4: due in the next 24 hours  # Later, this should add an anchor when we start putting anchors in pages.
 #  sub getLinkForResource {
 # code (curent solved status)      my $stack = shift;
 # 1: not attempted      my $res;
 # 2: attempted but wrong, or incorrect by instructor  
 # 3: solved or correct by instructor      # Check to see if there are any pages in the stack
 # 4: partially correct (one or more parts correct)      foreach $res (@$stack) {
 # "excused" needs to be supported, but is not yet.          if (defined($res) && $res->is_page()) {
 sub astatus {              return $res->src();
     my $rid=shift;  
     my $code=0;  
     my $ctext='';  
     $rid=~/(\d+)\.(\d+)/;  
     my $symb=&Apache::lonnet::declutter($hash{'map_id_'.$1}).'___'.$2.'___'.  
         &Apache::lonnet::declutter($hash{'src_'.$rid});  
     my %duedate=();  
     my %opendate=();  
     my %answerdate=();  
     # need to always check part 0's open/due/answer status  
     foreach (sort(split(/\,/,&Apache::lonnet::metadata($hash{'src_'.$rid},'allpo\ssiblekeys')))) {  
         if ($_=~/^parameter\_(.*)\_opendate$/) {  
             my $part=$1;  
             $duedate{$part}=&parmval($part.'.duedate',$symb);  
             $opendate{$part}=&parmval($part.'.opendate',$symb);  
             $answerdate{$part}=&parmval($part.'.answerdate',$symb);  
             if (&parmval($part.'.opendate.type',$symb) eq 'date_interval') {  
                 $opendate{$part}=$duedate{$part}-$opendate{$part};  
             }  
             if (&parmval($part.'.answerdate.type',$symb) eq 'date_interval') {  
                 $answerdate{$part}=$duedate{$part}+$answerdate{$part};  
             }  
         }          }
     }      }
     my $now=time;  
     my $tcode=0;  
   
     my %returnhash=&Apache::lonnet::restore($symb);      # Failing that, return the src of the last resource that is defined
       # (when we first recurse on a map, it puts an undefined resource
       # on the bottom because $self->{HERE} isn't defined yet, and we
       # want the src for the map anyhow)
       foreach (@$stack) {
           if (defined($_)) { $res = $_; }
       }
   
     foreach (sort(keys(%opendate))) {      return $res->src();
         my $duedate=$duedate{$_};  }
         my $opendate=$opendate{$_};  
         my $answerdate=$answerdate{$_};  # Convenience function: This seperates the logic of how to create
         my $preface='';  # the problem text strings ("Due: DATE", "Open: DATE", "Not yet assigned",
         unless ($_ eq '0') { $preface=' Part: '.$_.' '; }  # etc.) into a seperate function. It takes a resource object as the
         if ($opendate) {  # first parameter, and the part number of the resource as the second.
             if ($now<$duedate || (!$duedate)) {  # It's basically a big switch statement on the status of the resource.
                 unless ($tcode==4) { $tcode=2; }  
                 if ($duedate) {  sub getDescription {
                     $ctext.=$preface.'Due: '.localtime($duedate);      my $res = shift;
                 } else {      my $part = shift;
                     $ctext.=$preface.'No Due Date';      my $status = $res->status($part);
                 }  
                 if ($now<$opendate) {      if ($status == $res->NETWORK_FAILURE) { 
                     unless ($tcode) { $tcode=1; }          return "Having technical difficulties; please check status later"; 
                     $ctext.=$preface.'Open: '.localtime($opendate);      }
                 }      if ($status == $res->NOTHING_SET) {
                 if ($duedate && $duedate-$now<86400) {          return "Not currently assigned.";
                     $tcode=4;      }
                     $ctext.=$preface.'Due: '.localtime($duedate);      if ($status == $res->OPEN_LATER) {
                 }          return "Open " . timeToHumanString($res->opendate($part));
             } else {      }
                 unless (($tcode==4) || ($tcode eq 2)) { $tcode=3; }      if ($status == $res->OPEN) {
                 if ($now<$answerdate) {          if ($res->duedate($part)) {
                     $ctext.='Answer: '.localtime($duedate);              return "Due " . timeToHumanString($res->duedate($part));
                 }  
             }  
         } else {          } else {
             unless (($tcode==2) || ($tcode==4)) { $tcode=1; }              return "Open, no due date";
         }          }
               }
         my $status=$returnhash{'resource.'.$_.'.solved'};      if ($status == $res->PAST_DUE_ANSWER_LATER) {
                   return "Answer open " . timeToHumanString($res->answerdate($part));
         if ($status eq 'correct_by_student') {      }
             if ($code==0||$code==3) { $code=3; } else { $code=4; }      if ($status == $res->PAST_DUE_NO_ANSWER) {
             $ctext.=' solved';          return "Was due " . timeToHumanString($res->duedate($part));
         } elsif ($status eq 'correct_by_override') {      }
             if ($code==0||$code==3) { $code=3; } else { $code=4; }      if ($status == $res->ANSWER_OPEN) {
             $ctext.=' override';          return "Answer available";
         } elsif ($status eq 'incorrect_attempted') {      }
             if ($code!=4 && $code!=3) { $code=2; }      if ($status == $res->EXCUSED) {
             if ($code==3) { $code=4; }          return "Excused by instructor";
             $ctext.=' ('.      }
                 ($returnhash{'resource.'.$_.'.tries'}?      if ($status == $res->ATTEMPTED) {
                  $returnhash{'resource.'.$_.'.tries'}:'0');          return "Answer submitted, not yet graded.";
             my $numtries = &parmval($_.'.maxtries',$symb);      }
             if ($numtries) { $ctext.='/'.$numtries.' tries'; }      if ($status == $res->TRIES_LEFT) {
             $ctext.=')';          my $tries = $res->tries($part);
         } elsif ($status eq 'incorrect_by_override') {          my $maxtries = $res->maxtries($part);
             if ($code!=4 && $code!=3) { $code=2; }          my $triesString = "";
             if ($code==3) { $code=4; }          if ($tries && $maxtries) {
             $ctext.=' override';              $triesString = "<font size=\"-1\"><i>($tries of $maxtries tries used)</i></font>";
         } elsif ($status eq 'excused') {              if ($maxtries > 1 && $maxtries - $tries == 1) {
             if ($code==0||$code==3) { $code=3; } else { $code=4; }                  $triesString = "<b>$triesString</b>";
             $ctext.=' excused';              }
           }
           if ($res->duedate()) {
               return "Due " . timeToHumanString($res->duedate($part)) .
                   " $triesString";
         } else {          } else {
             if ($code==0) { $code=1; }              return "No due date $triesString";
         }          }
     }      }
       if ($status == $res->ANSWER_SUBMITTED) {
           return 'Answer submitted';
       }
   }
   
   # Convenience function, so others can use it: Is the problem due in less then
   # 24 hours, and still can be done?
   
     return 'p'.$code.$tcode.'"'.$ctext.'"';  sub dueInLessThen24Hours {
       my $res = shift;
       my $part = shift;
       my $status = $res->status($part);
   
       return ($status == $res->OPEN() ||
               $status == $res->TRIES_LEFT()) &&
              $res->duedate() && $res->duedate() < time()+(24*60*60) &&
              $res->duedate() > time();
 }  }
   
   # Convenience function, so others can use it: Is there only one try remaining for the
   # part, with more then one try to begin with, not due yet and still can be done?
   sub lastTry {
       my $res = shift;
       my $part = shift;
   
 sub addresource {      my $tries = $res->tries($part);
     my ($resource,$sofar,$rid,$showtypes,$indent,$linkid)=@_;      my $maxtries = $res->maxtries($part);
     if ($showtypes eq 'problems') {      return $tries && $maxtries && $maxtries > 1 &&
         if ($resource!~/\.(problem|exam|quiz|assess|survey|form)$/) {          $maxtries - $tries == 1 && $res->duedate() &&
             return;          $res->duedate() > time();
         }  }
   
   # This puts a human-readable name on the ENV variable.
   
   sub advancedUser {
       return $ENV{'request.role.adv'};
   }
   
   
   # timeToHumanString takes a time number and converts it to a
   # human-readable representation, meant to be used in the following
   # manner:
   # print "Due $timestring"
   # print "Open $timestring"
   # print "Answer available $timestring"
   # Very, very, very, VERY English-only... goodness help a localizer on
   # this func...
   sub timeToHumanString {
       my ($time) = @_;
       # zero, '0' and blank are bad times
       if (!$time) {
           return 'never';
     }      }
     my $brepriv=&Apache::lonnet::allowed('bre',$resource);  
     if ($hash{'src_'.$rid}) {      my $now = time();
         if (($brepriv eq '2') || ($brepriv eq 'F')) {  
             my $pprefix='';      my @time = localtime($time);
             if ($resource=~/\.(problem|exam|quiz|assess|survey|form)$/) {      my @now = localtime($now);
                 $pprefix=&astatus($rid);  
             }      # Positive = future
             $$sofar++;      my $delta = $time - $now;
             if ($indent) { $pprefix='i'.$indent.','.$pprefix; }  
             if ($linkid) { $pprefix='l'.$linkid.','.$pprefix; }      my $minute = 60;
             if (defined($rows[$$sofar])) {      my $hour = 60 * $minute;
                 $rows[$$sofar].='&'.$pprefix.$rid;      my $day = 24 * $hour;
             } else {      my $week = 7 * $day;
                 $rows[$$sofar]=$pprefix.$rid;      my $inPast = 0;
             }  
         }      # Logic in comments:
       # Is it now? (extremely unlikely)
       if ( $delta == 0 ) {
           return "this instant";
     }      }
 }  
   
 sub followlinks () {      if ($delta < 0) {
     my ($rid,$sofar,$beenhere,$further,$showtypes,$indent,$linkid)=@_;          $inPast = 1;
     my $mincond=1;          $delta = -$delta;
     my $next='';  
     foreach (split(/\,/,$hash{'to_'.$rid})) {  
         my $thiscond=  
             &Apache::lonnet::directcondval($hash{'condid_'.$hash{'undercond_'.$_}});  
         if ($thiscond>=$mincond) {  
             if ($next) {  
                 $next.=','.$_.':'.$thiscond;  
             } else {  
                 $next=$_.':'.$thiscond;  
             }  
             if ($thiscond>$mincond) { $mincond=$thiscond; }  
         }  
     }      }
     my $col=0;  
     &Apache::lonxml::debug("following links -$next-");      if ( $delta > 0 ) {
     foreach (split(/\,/,$next)) {  
         my ($nextlinkid,$condval)=split(/\:/,$_);          my $tense = $inPast ? " ago" : "";
         if ($condval>=$mincond) {          my $prefix = $inPast ? "" : "in ";
             my $now=&tracetable($sofar,$hash{'goesto_'.$nextlinkid},          
                                 $beenhere,$showtypes,$indent,$linkid);          # Less then a minute
             if ($now>$further) {                          if ( $delta < $minute ) {
                 if ($col>0) {              if ($delta == 1) { return "${prefix}1 second$tense"; }
                     my $string;              return "$prefix$delta seconds$tense";
                     for(my $i=0;$i<$col;$i++) { $string.='&'; }  
                     for(my $i=$further+1;$now-1>$i;$i++) {  
                         $rows[$i]=$string.$rows[$i];  
                     }  
                 }  
                 $further=$now;  
             }  
         }          }
         $col++;  
     }  
     return $further;  
 }  
 # ------------------------------------------------------------ Build page table  
   
 sub tracetable {          # Less then an hour
     my ($sofar,$rid,$beenhere,$showtypes,$indent,$linkid)=@_;          if ( $delta < $hour ) {
     my $newshowtypes=$showtypes;              # If so, use minutes
     my $further=$sofar;              my $minutes = floor($delta / 60);
 # $Apache::lonxml::debug=1;              if ($minutes == 1) { return "${prefix}1 minute$tense"; }
     &Apache::lonxml::debug("$rid ; $linkid ; $sofar ; $beenhere ; ".$hash{'src_'.$rid});              return "$prefix$minutes minutes$tense";
     if ($beenhere=~/\&$rid\&/) { return $further; }  
     $beenhere.=$rid.'&';  
   
     if (defined($hash{'is_map_'.$rid})) {  
         $sofar++;  
         my $tprefix='';  
         if ($hash{'map_type_'.$hash{'map_pc_'.$hash{'src_'.$rid}}}  
             eq 'sequence') {  
             $tprefix='h';  
         } elsif ($hash{'map_type_'.$hash{'map_pc_'.$hash{'src_'.$rid}}}  
                  eq 'page') {  
             $tprefix='j';  
             if ($indent) { $tprefix='i'.$indent.','.$tprefix; }  
             if ($linkid) { $tprefix='l'.$linkid.','.$tprefix; }  
             $newshowtypes='problems';  
             $indent++;  
             #if in a .page continue to link the encompising .page  
             if (!$linkid) { $linkid=$rid; }  
         }          }
         if (defined($rows[$sofar])) {          
             $rows[$sofar].='&'.$tprefix.$rid;          # Is it less then 24 hours away? If so,
         } else {          # display hours + minutes
             $rows[$sofar]=$tprefix.$rid;          if ( $delta < $hour * 24) {
               my $hours = floor($delta / $hour);
               my $minutes = floor(($delta % $hour) / $minute);
               my $hourString = "$hours hours";
               my $minuteString = ", $minutes minutes";
               if ($hours == 1) {
                   $hourString = "1 hour";
               }
               if ($minutes == 1) {
                   $minuteString = ", 1 minute";
               }
               if ($minutes == 0) {
                   $minuteString = "";
               }
               return "$prefix$hourString$minuteString$tense";
           }
   
           # Less then 5 days away, display day of the week and
           # HH:MM
           if ( $delta < $day * 5 ) {
               my $timeStr = strftime("%A, %b %e at %I:%M %P", localtime($time));
               $timeStr =~ s/12:00 am/midnight/;
               $timeStr =~ s/12:00 pm/noon/;
               return ($inPast ? "last " : "next ") .
                   $timeStr;
         }          }
         if ((defined($hash{'map_start_'.$hash{'src_'.$rid}})) &&          
             (defined($hash{'map_finish_'.$hash{'src_'.$rid}}))) {          # Is it this year?
             my $frid=$hash{'map_finish_'.$hash{'src_'.$rid}};          if ( $time[5] == $now[5]) {
             $sofar=&tracetable($sofar,$hash{'map_start_'.$hash{'src_'.$rid}},              # Return on Month Day, HH:MM meridian
                                '&'.$frid.'&',$newshowtypes,$indent,$linkid);              my $timeStr = strftime("on %A, %b %e at %I:%M %P", localtime($time));
             &addresource($hash{'src_'.$frid},\$sofar,$frid,$newshowtypes,              $timeStr =~ s/12:00 am/midnight/;
                          $indent,$linkid);              $timeStr =~ s/12:00 pm/noon/;
             if ($tprefix =~ /j$/) { $indent--; $linkid=''; }              return $timeStr;
         }          }
     } else {  
         &addresource($hash{'src_'.$rid},\$sofar,$rid,$showtypes,  
                      $indent,$linkid);  
     }  
   
     if (defined($hash{'to_'.$rid})) {          # Not this year, so show the year
         $further=&followlinks($rid,$sofar,$beenhere,$further,$showtypes,          my $timeStr = strftime("on %A, %b %e %G at %I:%M %P", localtime($time));
                               $indent,$linkid);          $timeStr =~ s/12:00 am/midnight/;
           $timeStr =~ s/12:00 pm/noon/;
           return $timeStr;
     }      }
   
     return $further;  
 }  }
   
 # ================================================================ Main Handler  
   
 sub handler {  =pod
     my $r=shift;  
   
     &Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING});  =head1 NAME
   
     if ($ENV{'form.jtest'} ne "1")  Apache::lonnavmap - Subroutines to handle and render the navigation
     {      maps
         return new_handle($r);  
     }  
   
 # ------------------------------------------- Set document type for header only  =head1 SYNOPSIS
   
     if ($r->header_only) {  The main handler generates the navigational listing for the course,
         if ($ENV{'browser.mathml'}) {  the other objects export this information in a usable fashion for
             $r->content_type('text/xml');  other modules.
         } else {  
             $r->content_type('text/html');  =head1 OVERVIEW
         }  
         $r->send_http_header;  X<lonnavmaps, overview> When a user enters a course, LON-CAPA examines the
         return OK;  course structure and caches it in what is often referred to as the
     }  "big hash" X<big hash>. You can see it if you are logged into
     my $requrl=$r->uri;  LON-CAPA, in a course, by going to /adm/test. (You may need to
     my $hashtied;  tweak the /home/httpd/lonTabs/htpasswd file to view it.) The
 # ----------------------------------------------------------------- Tie db file  content of the hash will be under the heading "Big Hash".
     my $fn;  
     if ($ENV{'request.course.fn'}) {  Big Hash contains, among other things, how resources are related
         $fn=$ENV{'request.course.fn'};  to each other (next/previous), what resources are maps, which 
         if (-e "$fn.db") {  resources are being chosen to not show to the student (for random
             if ((tie(%hash,'GDBM_File',"$fn.db",&GDBM_READER(),0640)) &&  selection), and a lot of other things that can take a lot of time
                 (tie(%parmhash,'GDBM_File',  to compute due to the amount of data that needs to be collected and
                      $ENV{'request.course.fn'}.'_parms.db',  processed.
                      &GDBM_READER(),0640))) {  
                 $hashtied=1;  Apache::lonnavmaps provides an object model for manipulating this
             }  information in a higher-level fashion then directly manipulating 
         }  the hash. It also provides access to several auxilary functions 
     }  that aren't necessarily stored in the Big Hash, but are a per-
     if (!$hashtied) {  resource sort of value, like whether there is any feedback on 
         $ENV{'user.error.msg'}="$requrl:bre:0:0:Course not initialized";  a given resource.
         return HTTP_NOT_ACCEPTABLE;   
     }  Apache::lonnavmaps also abstracts away branching, and someday, 
   conditions, for the times where you don't really care about those
   things.
   
   Apache::lonnavmaps also provides fairly powerful routines for
   rendering navmaps, and last but not least, provides the navmaps
   view for when the user clicks the NAV button.
   
   B<Note>: Apache::lonnavmaps I<only> works for the "currently
   logged in user"; if you want things like "due dates for another
   student" lonnavmaps can not directly retrieve information like
   that. You need the EXT function. This module can still help,
   because many things, such as the course structure, are constant
   between users, and Apache::lonnavmaps can help by providing
   symbs for the EXT call.
   
   The rest of this file will cover the provided rendering routines, 
   which can often be used without fiddling with the navmap object at
   all, then documents the Apache::lonnavmaps::navmap object, which
   is the key to accessing the Big Hash information, covers the use
   of the Iterator (which provides the logic for traversing the 
   somewhat-complicated Big Hash data structure), documents the
   Apache::lonnavmaps::Resource objects that are returned by 
   
   =head1 Subroutine: render
   
   The navmap renderer package provides a sophisticated rendering of the
   standard navigation maps interface into HTML. The provided nav map
   handler is actually just a glorified call to this.
   
   Because of the large number of parameters this function accepts,
   instead of passing it arguments as is normal, pass it in an anonymous
   hash with the desired options.
   
   The package provides a function called 'render', called as
   Apache::lonnavmaps::render({}).
   
   =head2 Overview of Columns
   
   The renderer will build an HTML table for the navmap and return
   it. The table is consists of several columns, and a row for each
   resource (or possibly each part). You tell the renderer how many
   columns to create and what to place in each column, optionally using
   one or more of the prepared columns, and the renderer will assemble
   the table.
   
   Any additional generally useful column types should be placed in the
   renderer code here, so anybody can use it anywhere else. Any code
   specific to the current application (such as the addition of <input>
   elements in a column) should be placed in the code of the thing using
   the renderer.
   
   At the core of the renderer is the array reference COLS (see Example
   section below for how to pass this correctly). The COLS array will
   consist of entries of one of two types of things: Either an integer
   representing one of the pre-packaged column types, or a sub reference
   that takes a resource reference, a part number, and a reference to the
   argument hash passed to the renderer, and returns a string that will
   be inserted into the HTML representation as it.
   
 # ------------------------------------------------------------------- Hash tied  All other parameters are ways of either changing how the columns
   are printing, or which rows are shown.
   
     if ($ENV{'browser.mathml'}) {  The pre-packaged column names are refered to by constants in the
         $r->content_type('text/xml');  Apache::lonnavmaps namespace. The following currently exist:
     } else {  
         $r->content_type('text/html');  
     }  
     &Apache::loncommon::no_cache($r);  
     $r->send_http_header;  
   
     my $firstres=$hash{'map_start_'.  =over 4
            &Apache::lonnet::clutter($ENV{'request.course.uri'})};  
     my $lastres=$hash{'map_finish_'.  
            &Apache::lonnet::clutter($ENV{'request.course.uri'})};  
     if (!(($firstres) && ($lastres))) {  
         $r->print('<html><body>Coursemap undefined.</body></html>');  
     } else {  
   
 # ----------------------------------------------------------------- Render page  =item * B<Apache::lonnavmaps::resource>:
 # -------------------------------------------------------------- Set parameters  
   
   The general info about the resource: Link, icon for the type, etc. The
   first column in the standard nav map display. This column provides the
   indentation effect seen in the B<NAV> screen. This column also accepts
   the following parameters in the renderer hash:
   
 # ---------------------------- initialize coursedata and userdata for this user  =over 4
         undef %courseopt;  
         undef %useropt;  
   
         my $uname=$ENV{'user.name'};  
         my $udom=$ENV{'user.domain'};  
         my $uhome=$ENV{'user.home'};  
         my $cid=$ENV{'request.course.id'};  
         my $chome=$ENV{'course.'.$cid.'.home'};  
         my ($cdom,$cnum)=split(/\_/,$cid);  
   
         my $userprefix=$uname.'_'.$udom.'_';  =item * B<resource_nolink>: default false
           
         unless ($uhome eq 'no_host') {   
 # ------------------------------------------------- Get coursedata (if present)  
             unless ((time-$courserdatas{$cid.'.last_cache'})<240) {  
                 my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum.  
                                                  ':resourcedata',$chome);  
                 if ($reply!~/^error\:/) {  
                     $courserdatas{$cid}=$reply;  
                     $courserdatas{$cid.'.last_cache'}=time;  
                 }  
                 # check to see if network failed  
                 elsif ( $reply=~/no.such.host/i || $reply=~/con.*lost/i )  
                 {  
                     $networkFailedFlag = 1;  
                 }  
             }  
             foreach (split(/\&/,$courserdatas{$cid})) {  
                 my ($name,$value)=split(/\=/,$_);  
                 $courseopt{$userprefix.&Apache::lonnet::unescape($name)}=  
                     &Apache::lonnet::unescape($value);  
             }  
 # --------------------------------------------------- Get userdata (if present)  
             unless ((time-$userrdatas{$uname.'___'.$udom.'.last_cache'})<240) {  
                 my $reply=&Apache::lonnet::reply('dump:'.$udom.':'.$uname.':resourcedata',$uhome);  
                 if ($reply!~/^error\:/) {  
                     $userrdatas{$uname.'___'.$udom}=$reply;  
                     $userrdatas{$uname.'___'.$udom.'.last_cache'}=time;  
                 }  
             }  
             foreach (split(/\&/,$userrdatas{$uname.'___'.$udom})) {  
                 my ($name,$value)=split(/\=/,$_);  
                 $useropt{$userprefix.&Apache::lonnet::unescape($name)}=  
                     &Apache::lonnet::unescape($value);  
             }  
         }  
   
         @rows=();  If true, the resource will not be linked. By default, all non-folder
   resources are linked.
   
         &tracetable(0,$firstres,'&','',0);  =item * B<resource_part_count>: default true
   
 # ------------------------------------------------------------------ Page parms  If true, the resource will show a part count B<if> the full
   part list is not displayed. (See "condense_parts" later.) If false,
   the resource will never show a part count.
   
         my $j;  =item * B<resource_no_folder_link>:
         my $i;  
         my $lcm=1;  
         my $contents=0;  
   
 # ---------------------------------------------- Go through table to get layout  If true, the resource's folder will not be clickable to open or close
   it. Default is false. True implies printCloseAll is false, since you
   can't close or open folders when this is on anyhow.
   
         for ($i=0;$i<=$#rows;$i++) {  =back
             if ($rows[$i]) {  
                 &Apache::lonxml::debug("Row $i is:".$rows[$i]);  
                 $contents++;  
                 my @colcont=split(/\&/,$rows[$i]);  
                 $lcm*=($#colcont+1)/euclid($lcm,($#colcont+1));  
             }   
         }  
   
   =item B<Apache::lonnavmaps::communication_status>:
   
         unless ($contents) {  Whether there is discussion on the resource, email for the user, or
             $r->print('<html><body>Empty Map.</body></html>');  (lumped in here) perl errors in the execution of the problem. This is
         } else {  the second column in the main nav map.
   
 # ------------------------------------------------------------------ Build page  =item B<Apache::lonnavmaps::quick_status>:
   
             my $currenturl=$ENV{'form.postdata'};  An icon for the status of a problem, with five possible states:
             $currenturl=~s/^http\:\/\///;  Correct, incorrect, open, awaiting grading (for a problem where the
             $currenturl=~s/^[^\/]+//;  computer's grade is suppressed, or the computer can't grade, like
   essay problem), or none (not open yet, not a problem). The
 # ---------------------------------------------------------------- Send headers  third column of the standard navmap.
   
             my $date=localtime;  
             my $now=time;  
 # ----------------------------------------- Get email status and discussiontime  
   
             my %emailstatus=&Apache::lonnet::dump('email_status');  
             my $logouttime=$emailstatus{'logout'};  
             my $courseleave=$emailstatus{'logout_'.$ENV{'request.course.id'}};  
             my $lastcheck=($courseleave>$logouttime?$courseleave:$logouttime);  
   
             my %discussiontimes=&Apache::lonnet::dump('discussiontimes',  
                                                           $cdom,$cnum);  
   
             my %feedback=();  
             my %error=();  
             foreach my $msgid (split(/\&/,&Apache::lonnet::reply('keys:'.  
                                                                  $ENV{'user.domain'}.':'.  
                                                                  $ENV{'user.name'}.':nohist_email',  
                                                                  $ENV{'user.home'}))) {  
                 $msgid=&Apache::lonnet::unescape($msgid);  
                 my $plain=&Apache::lonnet::unescape(&Apache::lonnet::unescape($msgid));  
                 if ($plain=~/(Error|Feedback) \[([^\]]+)\]/) {  
                     my ($what,$url)=($1,$2);  
                     my %status=  
                         &Apache::lonnet::get('email_status',[$msgid]);  
                     if ($status{$msgid}=~/^error\:/) {   
                         $status{$msgid}='';   
                     }  
                           
                     if (($status{$msgid} eq 'new') ||   
                         (!$status{$msgid})) {   
                         if ($what eq 'Error') {  
                             $error{$url}.=','.$msgid;   
                         } else {  
                             $feedback{$url}.=','.$msgid;  
                         }  
                     }  
                 }  
             }  
 # ----------------------------------------------------------- Start Page Output  
             my $bodytagadd='';  
             $r->print(  
                    '<html><head><title>Navigate Course Map</title></head>');  
             if (($currenturl=~/^\/res/) &&  
                 ($currenturl!~/^\/res\/adm/)) {  
                 $bodytagadd='onLoad="window.location.hash='."'curloc'".'"';  
             }  
             $r->print(&Apache::loncommon::bodytag('Navigate Course Map','',  
                                                   $bodytagadd));  
             $r->print('<script>window.focus();</script>');  
             my $desc=$ENV{'course.'.$ENV{'request.course.id'}.'.description'};  
             if (defined($desc)) { $r->print("<h2>$desc</h2>\n"); }  
             $r->print("<h3>$date</h3>\n");  
             $r->rflush();  
             $r->print('<img src="/adm/lonMisc/chat.gif"> New discussion since '.  
                       localtime($lastcheck).  
                       '<br><img src="/adm/lonMisc/feedback.gif"> New message (click to open)<p>');   
             if (($currenturl=~/^\/res/) &&  
                 ($currenturl!~/^\/res\/adm/)) {  
                 $r->print('<a href="#curloc">Current Location</a><p>');  
             }  
   
             # Handle a network error  =item B<Apache::lonnavmaps::long_status>:
   
             if ($networkFailedFlag)  A text readout of the details of the current status of the problem,
             {  such as "Due in 22 hours". The fourth column of the standard navmap.
                 $r->print('<H2>LON-CAPA network failure.</H2>'."\n");  
                 $r->print("<p>LON-CAPA's network is having difficulties, some problem" .  
                           " information, such as due dates, will not be available.");  
             }  
 # ----------------------------------------------------- The little content list  
             for ($i=0;$i<=$#rows;$i++) {  
                 if ($rows[$i]) {  
                     my @colcont=split(/\&/,$rows[$i]);  
                     my $avespan=$lcm/($#colcont+1);  
                     for ($j=0;$j<=$#colcont;$j++) {  
                         my $rid=$colcont[$j];  
                         if ($rid=~/^h(.+)/) {  
                             $rid=$1;  
                             $r->print('&nbsp;&nbsp;&nbsp;<a href="#'.  
                                       $rid.'">'.$hash{'title_'.$rid}.  
                                       '</a><br>');  
                         }  
                     }  
                 }  
             }  
 # ----------------------------------------------------------------- Start table  
             $r->print('<hr><table cols="'.$lcm.'" border="0">');  
             for ($i=0;$i<=$#rows;$i++) {  
                 if ($rows[$i]) {  
                     $r->print("\n<tr>");  
                     my @colcont=split(/\&/,$rows[$i]);  
                     my $avespan=$lcm/($#colcont+1);  
   
                     # for each item I wish to print on this row...  
                     for ($j=0;$j<=$#colcont;$j++) {  
                         my $indent;my $indentstr;  
                         my $linkid;  
                         my $rid=$colcont[$j];  
                         $rid=~/(\d+)\.(\d+)$/;  
                         my $src=  
                            &Apache::lonnet::declutter($hash{'src_'.$1.'.'.$2});  
                         my $symb=  
           &Apache::lonnet::declutter($hash{'map_id_'.$1}).'___'.$2.'___'.$src;  
                         my $add='<td>';  
                         my $adde='</td>';  
                         my $hwk='<font color="#223322">';  
                         my $hwke='</font>';  
                         if ($rid=~/^l(\d+\.\d+),(.+)/) { $linkid=$1; $rid=$2; }  
                         if ($rid=~/^i(\d+),(.+)/) { $indent=$1; $rid=$2; }  
                         if ($rid=~/^h(.+)/) {  
                             $rid=$1;  
                             $add='<th bgcolor="#AAFF55"><a name="'.$rid.'">';  
                             $adde='</th>';  
                             if (($ENV{'user.adv'}) &&   
                                 ($parmhash{$symb.'.0.parameter_randompick'})) {  
                                $adde=' (randomly select '.  
                                    $parmhash{$symb.'.0.parameter_randompick'}.  
                                    ')</th>';  
                             }  
                         }  
                         if ($rid=~/^j(.+)/) { $rid=$1; }  
                         if ($rid=~/^p(\d)(\d)\"([\w\: \(\)\/\,]*)\"(.+)/) {  
                             # sub astatus describes what code/tcode mean  
                             my $code=$1;  
                             my $tcode=$2;  
                             my $ctext=$3;  
                             $rid=$4;  
                               
                             # will open later  
                             if ($tcode eq '1') {   
                                 $add='<td bgcolor="#AAAAAA">';  
                             }  
   
                             # solved/correct  
                             if ($code eq '3') {  
                                 $add='<td bgcolor="#AAFFAA">';  
                             } elsif ($code eq '4') { # partially correct  
                                 $add='<td bgcolor="#E0FFAA">';  
                             } else {  
                                 # not attempted  
                                   
                                 # we end up here on network failure, so pick a neutral  
                                 # color if the network failed instead of bright red.  
                                 if ( $networkFailedFlag )  
                                 {  
                                     $add = '<td bgcolor="#AAAAAA">';  
                                 }  
                                 else  
                                 {  
                                     $add='<td bgcolor="#FFAAAA">';  
                                 }  
   
                                 if ($tcode eq '2') { # open, not past due  
                                     $add='<td bgcolor="#FFFFAA">';  
                                 }  
   
                                 if ($tcode eq '4') { # due in next 24 hours  
                                     $add='<td bgcolor="#FFFF33">';  
                                     $adde='</td>';  
                                 }  
                             }  
                             $hwk='<font color="#888811"><b>';  
                             $hwke='</b></font>';  
                             if ($code eq '1') {  
                                 $hwke='</b> ('.$ctext.')</font>';  
                             }  
                             if ($code eq '2' || $code eq '4') {  
                                 $hwk='<font color="#992222"><b>';  
                                 $hwke='</b> ('.$ctext.')</font>';  
                             }  
                             if ($code eq '3') {  
                                 $hwk='<font color="#229922"><b>';  
                                 $hwke='</b> ('.$ctext.')</font>';  
                             }  
                             if ($networkFailedFlag)   
                             {  
                                 $hwke='</b> (status unavailable)</font>';  
                             }  
                         }  
                         if ($rid && $hash{'src_'.$rid} eq $currenturl) {  
                             $add=$add.'<a name="curloc"></a>'.  
                                 '<font color=red size=+2><b>&gt; </b></font>';  
                             $adde=  
                                 '<font color=red size=+2><b> &lt;</b></font>'.$adde;  
                         }  
                         if ($discussiontimes{$symb}>$lastcheck) {  
                             $adde=  
                                 '<img border=0 src="/adm/lonMisc/chat.gif">'.  
                                     $adde;  
                         }  
                         if ($error{$src}) {  
                             foreach (split(/\,/,$error{$src})) {  
                                 if ($_) {  
                                     $adde=  
                                         '&nbsp;<a href="/adm/email?display='.  
                                             &Apache::lonnet::escape($_).  
                                                 '"><img src="/adm/lonMisc/bomb.gif" border=0></a>'  
                                                     .$adde;  
                                 }  
                             }  
                         }  
                         if ($feedback{$src}) {  
                             foreach (split(/\,/,$feedback{$src})) {  
                                 if ($_) {  
                                     $adde=  
                                         '&nbsp;<a href="/adm/email?display='.  
                                             &Apache::lonnet::escape($_).  
                                                 '"><img src="/adm/lonMisc/feedback.gif" border=0></a>'  
                                                     .$adde;  
                                 }  
                             }  
                         }  
                         if ($indent) {  
                             my $is="&nbsp;&nbsp;";  
                             for(my $i=-1;$i<$indent;$i++) { $indentstr.=$is; }  
                         }  
                         if (!$linkid) { $linkid=$rid; }  
                         if ($hash{'randomout_'.$rid}) {  
                             $adde=' <i>(hidden)</i>'.$adde;  
                         }  
                         $r->print($add.$indentstr);  
                         if ($rid) {  
                             $r->print('<a href="'.$hash{'src_'.$linkid}.  
                                       (($hash{'src_'.$linkid}=~/\?/)?'&':'?').  
                                       'symb='.&Apache::lonnet::escape($symb)  
                                        .'">'.  
                                       $hwk.$hash{'title_'.$rid}.$hwke.'</a>');  
                         }  
                         $r->print($adde);  
                     }  
                     $r->print('</tr>');  
                 }  
             }  
             $r->print("\n</table>");  
             $r->print('</body></html>');  
 # -------------------------------------------------------------------- End page  
         }                    
 # ------------------------------------------------------------- End render page  
     }  
 # ------------------------------------------------------------------ Untie hash  
     unless (untie(%hash)) {  
         &Apache::lonnet::logthis("<font color=blue>WARNING: ".  
                                  "Could not untie coursemap $fn (browse).</font>");   
     }  
     unless (untie(%parmhash)) {  
         &Apache::lonnet::logthis("<font color=blue>WARNING: ".  
                                  "Could not untie parmhash (browse).</font>");   
     }  
     return OK;  
 }  
   
 sub new_handle {  =back
     my $r = shift;  
   
     # Handle header-only request  If you add any others please be sure to document them here.
     if ($r->header_only) {  
         if ($ENV{'browser.mathml'}) {  
             $r->content_type('text/xml');  
         } else {  
             $r->content_type('text/html');  
         }  
         $r->send_http_header;  
         return OK;  
     }  
   
     # Send header, don't cache this page  An example of a column renderer that will show the ID number of a
     if ($ENV{'browser.mathml'}) {  resource, along with the part name if any:
         $r->content_type('text/xml');  
     } else {  
         $r->content_type('text/html');  
     }  
     &Apache::loncommon::no_cache($r);  
     $r->send_http_header;  
   
     # Initialize the nav map   sub { 
     my $navmap = Apache::lonnavmaps::navmap->new(    my ($resource, $part, $params) = @_;   
                         $ENV{"request.course.fn"}.".db",    if ($part) { return '<td>' . $resource->{ID} . ' ' . $part . '</td>'; }
                         $ENV{"request.course.fn"}."_parms.db", 1);    return '<td>' . $resource->{ID} . '</td>';
    }
   
   Note these functions are responsible for the TD tags, which allow them
   to override vertical and horizontal alignment, etc.
   
     if (!defined($navmap)) {  =head2 Parameters
         my $requrl = $r->uri;  
         $ENV{'user.error.msg'} = "$requrl:bre:0:0:Course not initialized";  
         return HTTP_NOT_ACCEPTABLE;  
     }  
   
     # Header  Minimally, you should be
     $r->print(&Apache::loncommon::bodytag('Navigate Course Map','',  able to get away with just using 'cols' (to specify the columns
                                           ''));  shown), 'url' (necessary for the folders to link to the current screen
     $r->print('<script>window.focus();</script>');  correctly), and possibly 'queryString' if your app calls for it. In
     my $desc=$ENV{'course.'.$ENV{'request.course.id'}.'.description'};  that case, maintaining the state of the folders will be done
     if (defined($desc)) { $r->print("<h2>$desc</h2>\n"); }  automatically.
     my $date=localtime;  
     $r->print("<h3>$date</h3>\n");  
     $r->rflush();  
     $r->print('<img src="/adm/lonMisc/chat.gif"> New discussion since '.  
       timeToHumanString($navmap->{LAST_CHECK}).  
       '<br><img src="/adm/lonMisc/feedback.gif"> New message (click to open)<p>');   
     #if (($currenturl=~/^\/res/) &&  
     #    ($currenturl!~/^\/res\/adm/)) {  
     #    $r->print('<a href="#curloc">Current Location</a><p>');  
     #}  
   
     # Check that it's defined  =over 4
     if (!($navmap->courseMapDefined())) {  
         $r->print('<font size="+2" color="red">Coursemap undefined.</font>' .  
                   '</body></html>');  
         return OK;  
     }  
   
     # Grab a resource object so we have access to the constants; this  =item * B<iterator>: default: constructs one from %ENV
     # is technically not proper, but should be harmless  
     my $res = $navmap->firstResource();  
   
     # Defines a status->color mapping, null string means don't color  
     my %colormap =   
     ( $res->NETWORK_FAILURE        => '',  
       $res->CORRECT                => '',  
       $res->EXCUSED                => '#BBBBFF',  
       $res->PAST_DUE_ANSWER_LATER  => '',  
       $res->PAST_DUE_NO_ANSWER     => '',  
       $res->ANSWER_OPEN            => '#CCFFCC',  
       $res->OPEN_LATER             => '',  
       $res->TRIES_LEFT             => '',  
       $res->INCORRECT              => '',  
       $res->OPEN                   => '',  
       $res->NOTHING_SET            => ''        );  
     # And a special case in the nav map; what to do when the assignment  
     # is not yet done and due in less then 24 hours  
     my $hurryUpColor = "#FFCCCC";  
   
     my %statusIconMap =   
  ( $res->NETWORK_FAILURE    => '',  
   $res->NOTHING_SET        => '',  
   $res->CORRECT            => 'navmap.correct.gif',  
   $res->EXCUSED            => 'navmap.correct.gif',  
   $res->PAST_DUE_NO_ANSWER => 'navmap.wrong.gif',  
   $res->PAST_DUE_ANSWER_LATER => 'navmap.wrong.gif',  
   $res->ANSWER_OPEN        => 'navmap.wrong.gif',  
   $res->OPEN_LATER         => '',  
   $res->TRIES_LEFT         => 'navmap.open.gif',  
   $res->INCORRECT          => 'navmap.wrong.gif',  
   $res->OPEN               => 'navmap.open.gif' );  
   
     my %condenseStatuses =  A reference to a fresh ::iterator to use from the navmaps. The
  ( $res->NETWORK_FAILURE    => 1,  rendering will reflect the options passed to the iterator, so you can
   $res->NOTHING_SET        => 1,  use that to just render a certain part of the course, if you like. If
   $res->CORRECT            => 1 );  one is not passed, the renderer will attempt to construct one from
   ENV{'form.filter'} and ENV{'form.condition'} information, plus the
   'iterator_map' parameter if any.
   
     my %filterHash;  =item * B<iterator_map>: default: not used
     # Figure out what we're not displaying  
     foreach (split(/\,/, $ENV{"form.filter"})) {  
         if ($_) {  
             $filterHash{$_} = "1";  
         }  
     }  
   
     my $currenturl = $ENV{'form.postdata'};  If you are letting the renderer do the iterator handling, you can
     $currenturl=~s/^http\:\/\///;  instruct the renderer to render only a particular map by passing it
     $currenturl=~s/^[^\/]+//;  the source of the map you want to process, like
     my $queryAdd = "postdata=" . &Apache::lonnet::escape($currenturl);  '/res/103/jerf/navmap.course.sequence'.
   
     $r->print("$currenturl<br/>");  =item * B<navmap>: default: constructs one from %ENV
       
   
     # Begin the HTML table  A reference to a navmap, used only if an iterator is not passed in. If
     # four cols: resource + indent, chat+feedback, icon, text string  this is necessary to make an iterator but it is not passed in, a new
     $r->print('<table cellspacing="3" cellpadding="0" bgcolor="#FFFFFF">' ."\n");  one will be constructed based on ENV info. This is useful to do basic
   error checking before passing it off to render.
   
     my $mapIterator = $navmap->getIterator(undef, undef, \%filterHash, 0);  =item * B<r>: default: must be passed in
     my $curRes = $mapIterator->next();  
     undef $res; # so we don't accidentally use it later  
     my $indentLevel = -1;  
     my $indentString = "<img src=\"/adm/lonIcons/whitespace1.gif\" width=\"25\" height=\"1\" alt=\"\" border=\"0\" />";  
   
     my $isNewBranch = 0;  The standard Apache response object. This must be passed to the
     my $now = time();  renderer or the course hash will be locked.
     my $in24Hours = $now + 24 * 60 * 60;  
   
     while ($curRes != $mapIterator->END_NAV_MAP) {  =item * B<cols>: default: empty (useless)
         if ($curRes == $mapIterator->BEGIN_MAP() ||  
             $curRes == $mapIterator->BEGIN_BRANCH()) {  
             $indentLevel++;  
         }  
         if ($curRes == $mapIterator->END_MAP() ||  
             $curRes == $mapIterator->END_BRANCH()) {  
             $indentLevel--;  
         }  
         if ($curRes == $mapIterator->BEGIN_BRANCH()) {  
             $isNewBranch = 1;  
         }  
   
         if (ref($curRes) && $curRes->src()) {  
   
     # Step one: Decide which parts to show  
     my @parts = @{$curRes->parts()};  
     my $multipart = scalar(@parts) > 1;  
     my $condensed = 0;  
   
             if ($curRes->is_problem()) {  
  # Is it multipart?  
   
  if ($multipart) {  
     # If it's multipart, see if part 0 is "open"  
     # if it is, display all parts, if it isn't,  
     # just display first  
     if (!$curRes->opendate("0")) {  
  @parts = ("0"); # just display the zero-th part  
     } else {  
  # Otherwise, only display part 0 if we want to   
  # attach feedback or email information to it  
  if ($curRes->hasDiscussion() || $curRes->getFeedback()) {  
     shift @parts;  
  } else {  
     # If there's discussion or feedback, that counts  
     # as a difference, so display the parts.  
       
     # Now, we decide whether to condense the  
     # parts due to similarity  
     my $status = $curRes->status($parts[1]);  
     my $due = $curRes->duedate($parts[1]);  
     my $open = $curRes->opendate($parts[1]);  
     my $statusAllSame = 1;  
     my $dueAllSame = 1;  
     my $openAllSame = 1;  
     for (my $i = 2; $i < scalar(@parts); $i++) {  
  if ($curRes->status($parts[$i]) != $status){  
     $statusAllSame = 0;  
  }  
  if ($curRes->duedate($parts[$i]) != $due ) {  
     $dueAllSame = 0;  
  }  
  if ($curRes->opendate($parts[$i]) != $open) {  
     $openAllSame = 0;  
  }  
     }  
       
     # $allSame is true if all the statuses were  
     # the same. Now, if they are all the same and  
     # match one of the statuses to condense, or they  
     # are all open with the same due date, or they are  
     # all OPEN_LATER with the same open date, display the  
     # status of the first non-zero part (to get the 'correct'  
     # status right, since 0 is never 'correct' or 'open').  
     if (($statusAllSame && defined($condenseStatuses{$status})) ||  
  ($dueAllSame && $status == $curRes->OPEN && $statusAllSame)||  
  ($openAllSame && $status == $curRes->OPEN_LATER && $statusAllSame) ){  
  @parts = ($parts[1]);  
  $condensed = 1;  
     }  
  }  
     }  
  }  
   
             } else {  An array reference
                 @parts[0] = "0"; # this is to get past foreach loop below  
                  # you can consider a non-problem resource as a resource  
                  # with only one part without loss  
             }  
   
     # Step two: Show the parts  =item * B<showParts>:default true
             foreach my $part (@parts) {  
   
  my $deltalevel = 0; # for inserting the branch icon  A flag. If true, a line for the resource itself, and a line
                   for each part will be displayed. If not, only one line for each
                 # For each thing we're displaying...  resource will be displayed.
   
                 my $stack = $mapIterator->getStack();  =item * B<condenseParts>: default true
                 my $src = getLinkForResource($stack);  
   
                 my $srcHasQuestion = $src =~ /\?/;  A flag. If true, if all parts of the problem have the same
                 my $link = $src.  status and that status is Nothing Set, Correct, or Network Failure,
                     ($srcHasQuestion?'&':'?') .  then only one line will be displayed for that resource anyhow. If no,
                     'symb='.&Apache::lonnet::escape($curRes->symb()).  all parts will always be displayed. If showParts is 0, this is
                     '"';  ignored.
                 my $title = $curRes->title();  
                 my $partLabel = "";  
                 my $newBranchText = "";  
   
                 # If this is a new branch, label it so  
                 # (temporary, this should be an icon w/ alt text)  
                 if ($isNewBranch) {  
                     $newBranchText = "<img src=\"/adm/lonIcons/branch.gif\" border=\"0\">";  
                     $isNewBranch = 0;  
     $deltalevel = 1;  
                 }  
   
                 # links to open and close the folders  =item * B<jumpCount>: default: determined from %ENV
                 my $linkopen = "<a href=\"$link\">";  
                 my $linkclose = "</a>";  
   
                 my $icon = "<img src=\"/adm/lonIcons/html.gif\" alt=\"\" border=\"0\" />";  
                 if ($curRes->is_problem()) {   
     if ($part eq "0" || $condensed) {  
  $icon = '<img src="/adm/lonIcons/problem.gif" alt="" border=\"0\" />';   
     } else {  
  $icon = $indentString;  
     }  
                 }  
   
                 # Display the correct icon, link to open or shut map  A string identifying the URL to place the anchor 'curloc' at.
                 if ($curRes->is_map()) {   It is the responsibility of the renderer user to
                     my $mapId = $curRes->map_pc();  ensure that the #curloc is in the URL. By default, determined through
                     my $nowOpen = !defined($filterHash{$mapId});  the use of the ENV{} 'jump' information, and should normally "just
                     $icon = $nowOpen ?  work" correctly.
                         "folder_closed.gif" : "folder_opened.gif";  
     $icon = "<img src=\"/adm/lonIcons/$icon\" alt=\"\" border=\"0\" />";  
                     $linkopen = "<a href=\"/adm/navmaps?filter=";  
                     $linkopen .= $nowOpen ?   
                         addToFilter(\%filterHash, $mapId) :  
                         removeFromFilter(\%filterHash, $mapId);  
                     $linkopen .= "&$queryAdd\">";  
                     $linkclose = "</a>";  
                       
                 }  
                   
                 my $colorizer = "";  
                 if ($curRes->is_problem()) {  
                     my $status = $curRes->status($part);  
                     my $color = $colormap{$status};  
                     if ($color ne "") {  
                         $colorizer = "bgcolor=\"$color\"";  
                     }  
                 }  
   
  # FIRST ROW: The resource indentation, branch icon, and name  =item * B<here>: default: empty string
                 $r->print("  <tr><td align=\"left\" valign=\"top\">\n");  
   
                 # print indentation  A Symb identifying where to place the 'here' marker. The empty
                 for (my $i = 0; $i < $indentLevel - $deltalevel; $i++) {  string means no marker.
                     $r->print($indentString);  
                 }  
   
                 $r->print("  ${newBranchText}${linkopen}$icon${linkclose}\n");  =item * B<indentString>: default: 25 pixel whitespace image
   
                 if ($curRes->is_problem() && $part != "0" && !$condensed) {   A string identifying the indentation string to use. 
     $partLabel = " (Part $part)";   
     $title = "";  
  }  
   
                 $r->print("  <a href=\"$link\">$title$partLabel</a></td>");  =item * B<queryString>: default: empty
   
  my $discussionHTML = ""; my $feedbackHTML = "";  A string which will be prepended to the query string used when the
   folders are opened or closed. You can use this to pass
   application-specific values.
   
  # SECOND ROW: Is there text or feedback?  =item * B<url>: default: none
  if ($curRes->hasDiscussion()) {  
     $discussionHTML = $linkopen .  
  '<img border="0" src="/adm/lonMisc/chat.gif" />' .  
  $linkclose;  
  }  
   
  if ($curRes->getFeedback()) {  The url the folders will link to, which should be the current
     my $feedback = $curRes->getFeedback();  page. Required if the resource info column is shown, and you 
     foreach (split(/\,/, $feedback)) {  are allowing the user to open and close folders.
  if ($_) {  
     $feedbackHTML .= '&nbsp;<a href="/adm/email?display='  
  . &Apache::lonnet::escape($_) . '">'  
  . '<img src="/adm/lonMisc/feedback.gif" '  
  . 'border="0" /></a>';  
  }  
     }  
  }  
   
  $r->print("<td align=\"left\">$discussionHTML$feedbackHTML</td>");  =item * B<currentJumpIndex>: default: no jumping
   
  # Is this the first displayed part of a multi-part problem  Describes the currently-open row number to cause the browser to jump
  # that has not been condensed, so we should suppress these two  to, because the user just opened that folder. By default, pulled from
  # columns?  the Jump information in the ENV{'form.*'}.
  my $firstDisplayed = !$condensed && $multipart && $part eq "0";  
   
  # THIRD ROW: Problem status icon  
  if ($curRes->is_problem() &&  
     !$firstDisplayed) {  
     my $icon = $statusIconMap{$curRes->status($part)};  
     if ($icon) {  
  $r->print("<td width=\"50\" align=\"right\">$linkopen<img src=\"/adm/lonIcons/$icon\" border=\"0\" />$linkclose</td>\n");  
     } else {  
  $r->print("<td></td>\n");  
     }  
  } else { # not problem, no icon  
     $r->print("<td></td>\n");  
  }  
   
   # FOURTH ROW: Text description  =item * B<printKey>: default: false
  $r->print("<td $colorizer align=\"right\">\n");  
                   
                 if ($curRes->kind() eq "res" &&  
                     $curRes->is_problem() &&  
     !$firstDisplayed) {  
                     $r->print (getDescription($curRes, $part));  
                 }  
   
  $r->print("</td></tr>\n");  If true, print the key that appears on the top of the standard
             }  navmaps.
   
   =item * B<printCloseAll>: default: true
   
   If true, print the "Close all folders" or "open all folders"
   links.
   
   =item * B<filterFunc>: default: sub {return 1;} (accept everything)
   
   A function that takes the resource object as its only parameter and
   returns a true or false value. If true, the resource is displayed. If
   false, it is simply skipped in the display.
   
   =item * B<suppressEmptySequences>: default: false
   
   If you're using a filter function, and displaying sequences to orient
   the user, then frequently some sequences will be empty. Setting this to
   true will cause those sequences not to display, so as not to confuse the
   user into thinking that if the sequence is there there should be things
   under it; for example, see the "Show Uncompleted Homework" view on the
   B<NAV> screen.
   
   =item * B<suppressNavmaps>: default: false
   
   If true, will not display Navigate Content resources. 
   
   =back
   
   =head2 Additional Info
   
   In addition to the parameters you can pass to the renderer, which will
   be passed through unchange to the column renderers, the renderer will
   generate the following information which your renderer may find
   useful:
   
   =over 4
   
   =item * B<counter>: 
   
   Contains the number of rows printed. Useful after calling the render 
   function, as you can detect whether anything was printed at all.
   
   =item * B<isNewBranch>:
   
   Useful for renderers: If this resource is currently the first resource
   of a new branch, this will be true. The Resource column (leftmost in the
   navmaps screen) uses this to display the "new branch" icon 
   
   =back
   
   =cut
   
   sub resource { return 0; }
   sub communication_status { return 1; }
   sub quick_status { return 2; }
   sub long_status { return 3; }
   
   # Data for render_resource
   
   sub render_resource {
       my ($resource, $part, $params) = @_;
   
       my $nonLinkedText = ''; # stuff after resource title not in link
   
       my $link = $params->{"resourceLink"};
       my $src = $resource->src();
       my $it = $params->{"iterator"};
       my $filter = $it->{FILTER};
   
       my $title = $resource->compTitle();
       if ($src =~ /^\/uploaded\//) {
           $nonLinkedText=$title;
           $title = '';
       }
       my $partLabel = "";
       my $newBranchText = "";
       
       # If this is a new branch, label it so
       if ($params->{'isNewBranch'}) {
           $newBranchText = "<img src='/adm/lonIcons/branch.gif' border='0' />";
       }
   
       # links to open and close the folder
       my $linkopen = "<a href='$link'>";
       my $linkclose = "</a>";
   
       # Default icon: unknown page
       my $icon = "<img src='/adm/lonIcons/unknown.gif' alt='' border='0' />";
       
       if ($resource->is_problem()) {
           if ($part eq '0' || $params->{'condensed'}) {
               $icon = '<img src="/adm/lonIcons/problem.gif" alt="" border="0" />';
           } else {
               $icon = $params->{'indentString'};
         }          }
         $curRes = $mapIterator->next();      } else {
    my $curfext= (split (/\./,$resource->src))[-1];
    my $embstyle = &Apache::loncommon::fileembstyle($curfext);
    # The unless conditional that follows is a bit of overkill
    if (!(!defined($embstyle) || $embstyle eq 'unk' || $embstyle eq 'hdn')) {
       $icon = "<img src='/adm/lonIcons/$curfext.gif' alt='' border='0' />";
    }
     }      }
   
     $r->print("</table></body></html>");      # Display the correct map icon to open or shut map
       if ($resource->is_map()) {
           my $mapId = $resource->map_pc();
           my $nowOpen = !defined($filter->{$mapId});
           if ($it->{CONDITION}) {
               $nowOpen = !$nowOpen;
           }
   
    my $folderType = $resource->is_sequence() ? 'folder' : 'page';
   
           if (!$params->{'resource_no_folder_link'}) {
               $icon = "navmap.$folderType." . ($nowOpen ? 'closed' : 'open') . '.gif';
               $icon = "<img src='/adm/lonIcons/$icon' alt='' border='0' />";
   
               $linkopen = "<a href='" . $params->{'url'} . '?' . 
                   $params->{'queryString'} . '&filter=';
               $linkopen .= ($nowOpen xor $it->{CONDITION}) ?
                   addToFilter($filter, $mapId) :
                   removeFromFilter($filter, $mapId);
               $linkopen .= "&condition=" . $it->{CONDITION} . '&hereType='
                   . $params->{'hereType'} . '&here=' .
                   &Apache::lonnet::escape($params->{'here'}) . 
                   '&jump=' .
                   &Apache::lonnet::escape($resource->symb()) . 
                   "&folderManip=1'>";
           } else {
               # Don't allow users to manipulate folder
               $icon = "navmap.$folderType." . ($nowOpen ? 'closed' : 'open') .
                   '.nomanip.gif';
               $icon = "<img src='/adm/lonIcons/$icon' alt='' border='0' />";
   
     $navmap->untieHashes();              $linkopen = "";
               $linkclose = "";
           }
       }
   
     return OK;      if ($resource->randomout()) {
 }          $nonLinkedText .= ' <i>(hidden)</i> ';
       }
       
       # We're done preparing and finally ready to start the rendering
       my $result = "<td align='left' valign='center'>";
   
 # Convenience functions: Returns a string that adds or subtracts      my $indentLevel = $params->{'indentLevel'};
 # the second argument from the first hash, appropriate for the       if ($newBranchText) { $indentLevel--; }
 # query string that determines which folders to recurse on  
 sub addToFilter {  
     my $hashIn = shift;  
     my $addition = shift;  
     my %hash = %$hashIn;  
     $hash{$addition} = 1;  
   
     return join (",", keys(%hash));      # print indentation
       for (my $i = 0; $i < $indentLevel; $i++) {
           $result .= $params->{'indentString'};
       }
   
       # Decide what to display
       $result .= "$newBranchText$linkopen$icon$linkclose";
       
       my $curMarkerBegin = '';
       my $curMarkerEnd = '';
   
       # Is this the current resource?
       if (!$params->{'displayedHereMarker'} && 
           $resource->symb() eq $params->{'here'} ) {
           $curMarkerBegin = '<font color="red" size="+2">&gt; </font>';
           $curMarkerEnd = '<font color="red" size="+2">&lt;</font>';
           $params->{'displayedHereMarker'} = 1;
       }
   
       if ($resource->is_problem() && $part ne '0' && 
           !$params->{'condensed'}) {
           $partLabel = " (Part $part)";
           $title = "";
       }
   
       if ($params->{'condensed'} && $resource->countParts() > 1) {
           $nonLinkedText .= ' (' . $resource->countParts() . ' parts)';
       }
   
       if (!$params->{'resource_nolink'} && $src !~ /^\/uploaded\// &&
    !$resource->is_sequence()) {
           $result .= "  $curMarkerBegin<a href='$link'>$title$partLabel</a>$curMarkerEnd $nonLinkedText</td>";
       } else {
           $result .= "  $curMarkerBegin$title$partLabel$curMarkerEnd $nonLinkedText</td>";
       }
   
       return $result;
 }  }
   
 sub removeFromFilter {  sub render_communication_status {
     my $hashIn = shift;      my ($resource, $part, $params) = @_;
     my $subtraction = shift;      my $discussionHTML = ""; my $feedbackHTML = ""; my $errorHTML = "";
     my %hash = %$hashIn;  
       my $link = $params->{"resourceLink"};
       my $linkopen = "<a href='$link'>";
       my $linkclose = "</a>";
   
       if ($resource->hasDiscussion()) {
           $discussionHTML = $linkopen .
               '<img border="0" src="/adm/lonMisc/chat.gif" />' .
               $linkclose;
       }
       
       if ($resource->getFeedback()) {
           my $feedback = $resource->getFeedback();
           foreach (split(/\,/, $feedback)) {
               if ($_) {
                   $feedbackHTML .= '&nbsp;<a href="/adm/email?display='
                       . &Apache::lonnet::escape($_) . '">'
                       . '<img src="/adm/lonMisc/feedback.gif" '
                       . 'border="0" /></a>';
               }
           }
       }
       
       if ($resource->getErrors()) {
           my $errors = $resource->getErrors();
           foreach (split(/,/, $errors)) {
               if ($_) {
                   $errorHTML .= '&nbsp;<a href="/adm/email?display='
                       . &Apache::lonnet::escape($_) . '">'
                       . '<img src="/adm/lonMisc/bomb.gif" '
                       . 'border="0" /></a>';
               }
           }
       }
   
       if ($params->{'multipart'} && $part != '0') {
    $discussionHTML = $feedbackHTML = $errorHTML = '';
       }
   
       return "<td width=\"75\" align=\"left\" valign=\"center\">$discussionHTML$feedbackHTML$errorHTML&nbsp;</td>";
   
     delete $hash{$subtraction};  
     return join(",", keys(%hash));  
 }  }
   sub render_quick_status {
       my ($resource, $part, $params) = @_;
       my $result = "";
       my $firstDisplayed = !$params->{'condensed'} && 
           $params->{'multipart'} && $part eq "0";
   
 # Convenience function: Given a stack returned from getStack on the iterator,      my $link = $params->{"resourceLink"};
 # return the correct src() value.      my $linkopen = "<a href='$link'>";
 # Later, this should add an anchor when we start putting anchors in pages.      my $linkclose = "</a>";
 sub getLinkForResource {  
     my $stack = shift;  
     my $res;  
   
     # Check to see if there are any pages in the stack      if ($resource->is_problem() &&
     foreach $res (@$stack) {          !$firstDisplayed) {
         if (defined($res) && $res->is_page()) {          my $icon = $statusIconMap{$resource->status($part)};
             return $res->src();          my $alt = $iconAltTags{$icon};
           if ($icon) {
               $result .= "<td width='30' valign='center' width='50' align='right'>$linkopen<img width='25' height='25' src='/adm/lonIcons/$icon' border='0' alt='$alt' />$linkclose</td>\n";
           } else {
               $result .= "<td width='30'>&nbsp;</td>\n";
         }          }
       } else { # not problem, no icon
           $result .= "<td width='30'>&nbsp;</td>\n";
     }      }
   
     # Failing that, return the src of the last resource that is defined      return $result;
     # (when we first recurse on a map, it puts an undefined resource  }
     # on the bottom because $self->{HERE} isn't defined yet, and we  sub render_long_status {
     # want the src for the map anyhow)      my ($resource, $part, $params) = @_;
     foreach (@$stack) {      my $result = "<td align='right' valign='center'>\n";
         if (defined($_)) { $res = $_; }      my $firstDisplayed = !$params->{'condensed'} && 
           $params->{'multipart'} && $part eq "0";
                   
       my $color;
       if ($resource->is_problem()) {
           $color = $colormap{$resource->status};
           
           if (dueInLessThen24Hours($resource, $part) ||
               lastTry($resource, $part)) {
               $color = $hurryUpColor;
           }
     }      }
       
       if ($resource->kind() eq "res" &&
           $resource->is_problem() &&
           !$firstDisplayed) {
           if ($color) {$result .= "<font color=\"$color\"><b>"; }
           $result .= getDescription($resource, $part);
           if ($color) {$result .= "</b></font>"; }
       }
       if ($resource->is_map() && advancedUser() && $resource->randompick()) {
           $result .= '(randomly select ' . $resource->randompick() .')';
       }
   
       # Debugging code
       #$result .= " " . $resource->awarded($part) . '/' . $resource->weight($part) .
       # ' - Part: ' . $part;
   
     return $res->src();      $result .= "</td>\n";
       
       return $result;
 }  }
   
 # Convenience function: This seperates the logic of how to create  my @preparedColumns = (\&render_resource, \&render_communication_status,
 # the problem text strings ("Due: DATE", "Open: DATE", "Not yet assigned",                         \&render_quick_status, \&render_long_status);
 # etc.) into a seperate function. It takes a resource object as the  
 # first parameter, and the part number of the resource as the second.  
 # It's basically a big switch statement on the status of the resource.  
   
 sub getDescription {  sub setDefault {
     my $res = shift;      my ($val, $default) = @_;
     my $part = shift;      if (!defined($val)) { return $default; }
     my $status = $res->getDateStatus();      return $val;
   }
   
     if ($status == $res->NETWORK_FAILURE) { return ""; }  sub render {
     if ($status == $res->NOTHING_SET) {      my $args = shift;
         return "Not currently assigned.";      &Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING});
       my $result = '';
   
       # Configure the renderer.
       my $cols = $args->{'cols'};
       if (!defined($cols)) {
           # no columns, no nav maps.
           return '';
       }
       my $mustCloseNavMap = 0;
       my $navmap;
       if (defined($args->{'navmap'})) {
           $navmap = $args->{'navmap'};
       }
   
       my $r = $args->{'r'};
       my $queryString = $args->{'queryString'};
       my $jump = $args->{'jump'};
       my $here = $args->{'here'};
       my $suppressNavmap = setDefault($args->{'suppressNavmap'}, 0);
       my $currentJumpDelta = 2; # change this to change how many resources are displayed
                                # before the current resource when using #current
   
       # If we were passed 'here' information, we are not rendering
       # after a folder manipulation, and we were not passed an
       # iterator, make sure we open the folders to show the "here"
       # marker
       my $filterHash = {};
       # Figure out what we're not displaying
       foreach (split(/\,/, $ENV{"form.filter"})) {
           if ($_) {
               $filterHash->{$_} = "1";
           }
     }      }
     if ($status == $res->OPEN_LATER) {  
         return "Opens: " . timeToHumanString($res->opendate($part));      # Filter: Remember filter function and add our own filter: Refuse
       # to show hidden resources unless the user can see them.
       my $userCanSeeHidden = advancedUser();
       my $filterFunc = setDefault($args->{'filterFunc'},
                                   sub {return 1;});
       if (!$userCanSeeHidden) {
           # Without renaming the filterfunc, the server seems to go into
           # an infinite loop
           my $oldFilterFunc = $filterFunc;
           $filterFunc = sub { my $res = shift; return !$res->randomout() && 
                                   &$oldFilterFunc($res);};
     }      }
     if ($status == $res->OPEN) {  
  if ($res->duedate()) {      my $condition = 0;
     return "Due: $status " . timeToHumanString($res->duedate($part));      if ($ENV{'form.condition'}) {
  } else {          $condition = 1;
     return "Open, no due date";  
  }  
     }      }
     if ($status == $res->PAST_DUE_ANSWER_LATER) {  
         return "Answer opens: " . timeToHumanString($res->answerdate($part));      if (!$ENV{'form.folderManip'} && !defined($args->{'iterator'})) {
           # Step 1: Check to see if we have a navmap
           if (!defined($navmap)) {
               $navmap = Apache::lonnavmaps::navmap->new();
               $mustCloseNavMap = 1;
           }
   
           # Step two: Locate what kind of here marker is necessary
           # Determine where the "here" marker is and where the screen jumps to.
   
           if ($ENV{'form.postsymb'}) {
               $here = $jump = $ENV{'form.postsymb'};
           } elsif ($ENV{'form.postdata'}) {
               # couldn't find a symb, is there a URL?
               my $currenturl = $ENV{'form.postdata'};
               #$currenturl=~s/^http\:\/\///;
               #$currenturl=~s/^[^\/]+//;
               
               $here = $jump = &Apache::lonnet::symbread($currenturl);
           }
   
           # Step three: Ensure the folders are open
           my $mapIterator = $navmap->getIterator(undef, undef, undef, 1);
           my $curRes;
           my $found = 0;
           
           # We only need to do this if we need to open the maps to show the
           # current position. This will change the counter so we can't count
           # for the jump marker with this loop.
           while (($curRes = $mapIterator->next()) && !$found) {
               if (ref($curRes) && $curRes->symb() eq $here) {
                   my $mapStack = $mapIterator->getStack();
                   
                   # Ensure the parent maps are open
                   for my $map (@{$mapStack}) {
                       if ($condition) {
                           undef $filterHash->{$map->map_pc()};
                       } else {
                           $filterHash->{$map->map_pc()} = 1;
                       }
                   }
                   $found = 1;
               }
           }            
       }        
   
       if ( !defined($args->{'iterator'}) && $ENV{'form.folderManip'} ) { # we came from a user's manipulation of the nav page
           # If this is a click on a folder or something, we want to preserve the "here"
           # from the querystring, and get the new "jump" marker
           $here = $ENV{'form.here'};
           $jump = $ENV{'form.jump'};
       } 
       
       my $it = $args->{'iterator'};
       if (!defined($it)) {
           # Construct a default iterator based on $ENV{'form.'} information
           
           # Step 1: Check to see if we have a navmap
           if (!defined($navmap)) {
               $navmap = Apache::lonnavmaps::navmap->new();
               $mustCloseNavMap = 1;
           }
   
           # See if we're being passed a specific map
           if ($args->{'iterator_map'}) {
               my $map = $args->{'iterator_map'};
               $map = $navmap->getResourceByUrl($map);
               my $firstResource = $map->map_start();
               my $finishResource = $map->map_finish();
   
               $args->{'iterator'} = $it = $navmap->getIterator($firstResource, $finishResource, $filterHash, $condition);
           } else {
               $args->{'iterator'} = $it = $navmap->getIterator(undef, undef, $filterHash, $condition);
           }
     }      }
     if ($status == $res->PAST_DUE_NO_ANSWER) {      
         return "Was Due: " . timeToHumanString($res->duedate($part));      # (re-)Locate the jump point, if any
       # Note this does not take filtering or hidden into account... need
       # to be fixed?
       my $mapIterator = $navmap->getIterator(undef, undef, $filterHash, 0);
       my $curRes;
       my $foundJump = 0;
       my $counter = 0;
       
       while (($curRes = $mapIterator->next()) && !$foundJump) {
           if (ref($curRes)) { $counter++; }
           
           if (ref($curRes) && $jump eq $curRes->symb()) {
               
               # This is why we have to use the main iterator instead of the
               # potentially faster DFS: The count has to be the same, so
               # the order has to be the same, which DFS won't give us.
               $args->{'currentJumpIndex'} = $counter;
               $foundJump = 1;
           }
     }      }
     if ($status == $res->ANSWER_OPEN) {  
         return "Answer available";      my $showParts = setDefault($args->{'showParts'}, 1);
       my $condenseParts = setDefault($args->{'condenseParts'}, 1);
       # keeps track of when the current resource is found,
       # so we can back up a few and put the anchor above the
       # current resource
       my $printKey = $args->{'printKey'};
       my $printCloseAll = $args->{'printCloseAll'};
       if (!defined($printCloseAll)) { $printCloseAll = 1; }
       
       # Print key?
       if ($printKey) {
           $result .= '<table border="0" cellpadding="2" cellspacing="0">';
           my $date=localtime;
           $result.='<tr><td align="right" valign="bottom">Key:&nbsp;&nbsp;</td>';
           if ($navmap->{LAST_CHECK}) {
               $result .= 
                   '<img src="/adm/lonMisc/chat.gif"> New discussion since '.
                   strftime("%A, %b %e at %I:%M %P", localtime($navmap->{LAST_CHECK})).
                   '</td><td align="center" valign="bottom">&nbsp;&nbsp;'.
                   '<img src="/adm/lonMisc/feedback.gif"> New message (click to open)<p>'.
                   '</td>'; 
           } else {
               $result .= '<td align="center" valign="bottom">&nbsp;&nbsp;'.
                   '<img src="/adm/lonMisc/chat.gif"> Discussions</td><td align="center" valign="bottom">'.
                   '&nbsp;&nbsp;<img src="/adm/lonMisc/feedback.gif"> New message (click to open)'.
                   '</td>'; 
           }
   
           $result .= '</tr></table>';
     }      }
     if ($status == $res->EXCUSED) {  
  return "Excused by instructor";      if ($printCloseAll && !$args->{'resource_no_folder_link'}) {
           if ($condition) {
               $result.="<a href=\"navmaps?condition=0&filter=&$queryString" .
                   "&here=" . Apache::lonnet::escape($here) .
                   "\">Close All Folders</a>";
           } else {
               $result.="<a href=\"navmaps?condition=1&filter=&$queryString" .
                   "&here=" . Apache::lonnet::escape($here) . 
                   "\">Open All Folders</a>";
           }
           $result .= "<br /><br />\n";
       }    
   
       if ($r) {
           $r->print($result);
           $r->rflush();
           $result = "";
       }
       # End parameter setting
               
       # Data
       $result .= '<table cellspacing="0" cellpadding="3" border="0" bgcolor="#FFFFFF">' ."\n";
       my $res = "Apache::lonnavmaps::resource";
       my %condenseStatuses =
           ( $res->NETWORK_FAILURE    => 1,
             $res->NOTHING_SET        => 1,
             $res->CORRECT            => 1 );
       my @backgroundColors = ("#FFFFFF", "#F6F6F6");
   
       # Shared variables
       $args->{'counter'} = 0; # counts the rows
       $args->{'indentLevel'} = 0;
       $args->{'isNewBranch'} = 0;
       $args->{'condensed'} = 0;    
       $args->{'indentString'} = setDefault($args->{'indentString'}, "<img src='/adm/lonIcons/whitespace1.gif' width='25' height='1' alt='' border='0' />");
       $args->{'displayedHereMarker'} = 0;
   
       # If we're suppressing empty sequences, look for them here. Use DFS for speed,
       # since structure actually doesn't matter, except what map has what resources.
       if ($args->{'suppressEmptySequences'}) {
           my $dfsit = Apache::lonnavmaps::DFSiterator->new($navmap,
                                                            $it->{FIRST_RESOURCE},
                                                            $it->{FINISH_RESOURCE},
                                                            {}, undef, 1);
           my $depth = 0;
           $dfsit->next();
           my $curRes = $dfsit->next();
           while ($depth > -1) {
               if ($curRes == $dfsit->BEGIN_MAP()) { $depth++; }
               if ($curRes == $dfsit->END_MAP()) { $depth--; }
   
               if (ref($curRes)) { 
                   # Parallel pre-processing: Do sequences have non-filtered-out children?
                   if ($curRes->is_map()) {
                       $curRes->{DATA}->{HAS_VISIBLE_CHILDREN} = 0;
                       # Sequences themselves do not count as visible children,
                       # unless those sequences also have visible children.
                       # This means if a sequence appears, there's a "promise"
                       # that there's something under it if you open it, somewhere.
                   } else {
                       # Not a sequence: if it's filtered, ignore it, otherwise
                       # rise up the stack and mark the sequences as having children
                       if (&$filterFunc($curRes)) {
                           for my $sequence (@{$dfsit->getStack()}) {
                               $sequence->{DATA}->{HAS_VISIBLE_CHILDREN} = 1;
                           }
                       }
                   }
               }
           } continue {
               $curRes = $dfsit->next();
           }
     }      }
     if ($status == $res->TRIES_LEFT) {  
  my $tries = $res->tries();      my $displayedJumpMarker = 0;
  my $maxtries = $res->maxtries();      # Set up iteration.
  my $triesString = "($tries of $maxtries tries used)";      my $now = time();
  if ($res->duedate()) {      my $in24Hours = $now + 24 * 60 * 60;
     return "Due: $status " . timeToHumanString($res->duedate($part)) .      my $rownum = 0;
  " $triesString";  
  } else {      # export "here" marker information
     return "No due date $triesString";      $args->{'here'} = $here;
   
       $args->{'indentLevel'} = -1; # first BEGIN_MAP takes this to 0
       while ($curRes = $it->next()) {
           # Maintain indentation level.
           if ($curRes == $it->BEGIN_MAP() ||
               $curRes == $it->BEGIN_BRANCH() ) {
               $args->{'indentLevel'}++;
           }
           if ($curRes == $it->END_MAP() ||
               $curRes == $it->END_BRANCH() ) {
               $args->{'indentLevel'}--;
           }
           # Notice new branches
           if ($curRes == $it->BEGIN_BRANCH()) {
               $args->{'isNewBranch'} = 1;
           }
   
           # If this isn't an actual resource, continue on
           if (!ref($curRes)) {
               next;
           }
   
           # If this has been filtered out, continue on
           if (!(&$filterFunc($curRes))) {
               $args->{'isNewBranch'} = 0; # Don't falsely remember this
               next;
           } 
   
           # If this is an empty sequence and we're filtering them, continue on
           if ($curRes->is_map() && $args->{'suppressEmptySequences'} &&
               !$curRes->{DATA}->{HAS_VISIBLE_CHILDREN}) {
               next;
           }
   
           # If we're suppressing navmaps and this is a navmap, continue on
           if ($suppressNavmap && $curRes->src() =~ /^\/adm\/navmaps/) {
               next;
           }
   
           $args->{'counter'}++;
   
           # Does it have multiple parts?
           $args->{'multipart'} = 0;
           $args->{'condensed'} = 0;
           my @parts;
               
           # Decide what parts to show.
           if ($curRes->is_problem() && $showParts) {
               @parts = @{$curRes->parts()};
               $args->{'multipart'} = $curRes->multipart();
               
               if ($condenseParts) { # do the condensation
                   if (!$curRes->opendate("0")) {
                       @parts = ();
                       $args->{'condensed'} = 1;
                   }
                   if (!$args->{'condensed'}) {
                       # Decide whether to condense based on similarity
                       my $status = $curRes->status($parts[0]);
                       my $due = $curRes->duedate($parts[0]);
                       my $open = $curRes->opendate($parts[0]);
                       my $statusAllSame = 1;
                       my $dueAllSame = 1;
                       my $openAllSame = 1;
                       for (my $i = 1; $i < scalar(@parts); $i++) {
                           if ($curRes->status($parts[$i]) != $status){
                               $statusAllSame = 0;
                           }
                           if ($curRes->duedate($parts[$i]) != $due ) {
                               $dueAllSame = 0;
                           }
                           if ($curRes->opendate($parts[$i]) != $open) {
                               $openAllSame = 0;
                           }
                       }
                       # $*allSame is true if all the statuses were
                       # the same. Now, if they are all the same and
                       # match one of the statuses to condense, or they
                       # are all open with the same due date, or they are
                       # all OPEN_LATER with the same open date, display the
                       # status of the first non-zero part (to get the 'correct'
                       # status right, since 0 is never 'correct' or 'open').
                       if (($statusAllSame && defined($condenseStatuses{$status})) ||
                           ($dueAllSame && $status == $curRes->OPEN && $statusAllSame)||
                           ($openAllSame && $status == $curRes->OPEN_LATER && $statusAllSame) ){
                           @parts = ($parts[0]);
                           $args->{'condensed'} = 1;
                       }
                   }
    # Multipart problem with one part: always "condense" (happens
    #  to match the desirable behavior)
    if ($curRes->countParts() == 1) {
       @parts = ($parts[0]);
       $args->{'condensed'} = 1;
    }
               }
           } 
               
           # If the multipart problem was condensed, "forget" it was multipart
           if (scalar(@parts) == 1) {
               $args->{'multipart'} = 0;
           } else {
               # Add part 0 so we display it correctly.
               unshift @parts, '0';
           }
   
           # Now, we've decided what parts to show. Loop through them and
           # show them.
           foreach my $part (@parts) {
               $rownum ++;
               my $backgroundColor = $backgroundColors[$rownum % scalar(@backgroundColors)];
               
               $result .= "  <tr bgcolor='$backgroundColor'>\n";
   
               # Set up some data about the parts that the cols might want
               my $filter = $it->{FILTER};
               my $stack = $it->getStack();
               my $src = getLinkForResource($stack);
               
               my $srcHasQuestion = $src =~ /\?/;
               $args->{"resourceLink"} = $src.
                   ($srcHasQuestion?'&':'?') .
                   'symb=' . &Apache::lonnet::escape($curRes->symb());
               
               # Now, display each column.
               foreach my $col (@$cols) {
                   my $colHTML = '';
                   if (ref($col)) {
                       $colHTML .= &$col($curRes, $part, $args);
                   } else {
                       $colHTML .= &{$preparedColumns[$col]}($curRes, $part, $args);
                   }
   
                   # If this is the first column and it's time to print
                   # the anchor, do so
                   if ($col == $cols->[0] && 
                       $args->{'counter'} == $args->{'currentJumpIndex'} - 
                       $currentJumpDelta) {
                       # Jam the anchor after the <td> tag;
                       # necessary for valid HTML (which Mozilla requires)
                       $colHTML =~ s/\>/\>\<a name="curloc" \/\>/;
                       $displayedJumpMarker = 1;
                   }
                   $result .= $colHTML . "\n";
               }
               $result .= "    </tr>\n";
               $args->{'isNewBranch'} = 0;
           }
   
           if ($r && $rownum % 20 == 0) {
               $r->print($result);
               $result = "";
               $r->rflush();
           }
       } continue {
    if ($r) {
       # If we have the connection, make sure the user is still connected
       my $c = $r->connection;
       if ($c->aborted()) {
    Apache::lonnet::logthis("navmaps aborted");
    # Who cares what we do, nobody will see it anyhow.
    return '';
       }
  }   }
     }      }
 }      
       # Print out the part that jumps to #curloc if it exists
       # delay needed because the browser is processing the jump before
       # it finishes rendering, so it goes to the wrong place!
       # onload might be better, but this routine has no access to that.
       # On mozilla, the 0-millisecond timeout seems to prevent this;
       # it's quite likely this might fix other browsers, too, and 
       # certainly won't hurt anything.
       if ($displayedJumpMarker) {
           $result .= "<script>setTimeout(\"location += '#curloc';\", 0)</script>\n";
       }
   
 # I want to change this into something more human-friendly. For      $result .= "</table>";
 # now, this is a simple call to localtime. The final function      
 # probably belongs in loncommon.      if ($r) {
 sub timeToHumanString {          $r->print($result);
     my ($time) = @_;          $result = "";
     # zero, '0' and blank are bad times          $r->rflush();
     if ($time) {  
  return localtime($time);  
     } else {  
  return 'Never';  
     }      }
           
       if ($mustCloseNavMap) { $navmap->untieHashes(); } 
   
       return $result;
 }  }
   
 1;  1;
   
 package Apache::lonnavmaps::navmap;  package Apache::lonnavmaps::navmap;
   
 # LEFT:  
 # * Actual handler code (multi-part)  
 # * Branches (aieee!) (and conditionals)  
   
 =pod  =pod
   
 lonnavmaps provides functions and objects for dealing with the compiled course hashes generated when a user enters the course, and also provides the Apache handler for the "Navigation Map" button.  =head1 Object: Apache::lonnavmaps::navmap
   
   =head2 Overview
   
   The navmap object's job is to provide access to the resources
   in the course as Apache::lonnavmaps::resource objects, and to
   query and manage the relationship between those resource objects.
   
   Generally, you'll use the navmap object in one of three basic ways.
   In order of increasing complexity and power:
   
   =over 4
   
   =item * C<$navmap-E<gt>getByX>, where X is B<Id>, B<Symb>, B<Url> or B<MapPc>. This provides
       various ways to obtain resource objects, based on various identifiers.
       Use this when you want to request information about one object or 
       a handful of resources you already know the identities of, from some
       other source. For more about Ids, Symbs, and MapPcs, see the
       Resource documentation. Note that Url should be a B<last resort>,
       not your first choice; it only works when there is only one
       instance of the resource in the course, which only applies to
       maps, and even that may change in the future.
   
   =item * C<my @resources = $navmap-E<gt>retrieveResources(args)>. This
       retrieves resources matching some criterion and returns them
       in a flat array, with no structure information. Use this when
       you are manipulating a series of resources, based on what map
       the are in, but do not care about branching, or exactly how
       the maps and resources are related. This is the most common case.
   
   =item * C<$it = $navmap-E<gt>getIterator(args)>. This allows you traverse
       the course's navmap in various ways without writing the traversal
       code yourself. See iterator documentation below. Use this when
       you need to know absolutely everything about the course, including
       branches and the precise relationship between maps and resources.
   
 =head1 navmap object: Encapsulating the compiled nav map  =back
   
 navmap is an object that encapsulates a compiled course map and provides a reasonable interface to it.  =head2 Creation And Destruction
   
 Most notably it provides a way to navigate the map sensibly and a flexible iterator that makes it easy to write various renderers based on nav maps.  To create a navmap object, use the following function:
   
   =over 4
   
 You must obtain resource objects through the navmap object.  =item * B<Apache::lonnavmaps::navmap-E<gt>new>():
   
   Creates a new navmap object. Returns the navmap object if this is
   successful, or B<undef> if not.
   
   =back
   
   When you are done with the $navmap object, you I<must> call 
   $navmap->untieHashes(), or you'll prevent the current user from using that 
   course until the web server is restarted. (!)
   
 =head2 Methods  =head2 Methods
   
 =over 4  =over 4
   
 =item * B<new>(filename, parmHashFile, genCourseAndUserOptions, genMailDiscussStatus): Binds a new navmap object to the compiled course representation and parmHashFile. genCourseAndUserOptions is a flag saying whether the course options and user options hash should be generated. This is for when you are using the parameters of the resources that require them; see documentation in resource object documentation. genMailDiscussStatus causes the nav map to retreive information about the email and discussion status of resources. Returns the navmap object if this is successful, or B<undef> if not. You must check for undef; errors will occur when you try to use the other methods otherwise.  =item * B<getIterator>(first, finish, filter, condition):
   
 =item * B<getIterator>(first, finish, filter, condition): See iterator documentation below.  See iterator documentation below.
   
 =cut  =cut
   
Line 1298  sub new { Line 1629  sub new {
     my $class = ref($proto) || $proto;      my $class = ref($proto) || $proto;
     my $self = {};      my $self = {};
   
     $self->{NAV_HASH_FILE} = shift;      # Resource cache stores navmap resources as we reference them. We generate
     $self->{PARM_HASH_FILE} = shift;  
     $self->{GENERATE_COURSE_USER_OPT} = shift;  
     $self->{GENERATE_EMAIL_DISCUSS_STATUS} = shift;  
   
     # Resource cache stores navmapresource's as we reference them. We generate  
     # them on-demand so we don't pay for creating resources unless we use them.      # them on-demand so we don't pay for creating resources unless we use them.
     $self->{RESOURCE_CACHE} = {};      $self->{RESOURCE_CACHE} = {};
   
Line 1312  sub new { Line 1638  sub new {
     $self->{NETWORK_FAILURE} = 0;      $self->{NETWORK_FAILURE} = 0;
   
     # tie the nav hash      # tie the nav hash
   
     my %navmaphash;      my %navmaphash;
     if (!(tie(%navmaphash, 'GDBM_File', $self->{NAV_HASH_FILE},      my %parmhash;
       my $courseFn = $ENV{"request.course.fn"};
       if (!(tie(%navmaphash, 'GDBM_File', "${courseFn}.db",
               &GDBM_READER(), 0640))) {                &GDBM_READER(), 0640))) {
         return undef;          return undef;
     }      }
     $self->{NAV_HASH} = \%navmaphash;  
           
     my %parmhash;      if (!(tie(%parmhash, 'GDBM_File', "${courseFn}_parms.db",
     if (!(tie(%parmhash, 'GDBM_File', $self->{PARM_HASH_FILE},  
               &GDBM_READER(), 0640)))                &GDBM_READER(), 0640)))
     {      {
  untie $self->{PARM_HASH};          untie %{$self->{PARM_HASH}};
         return undef;          return undef;
     }      }
   
       $self->{NAV_HASH} = \%navmaphash;
     $self->{PARM_HASH} = \%parmhash;      $self->{PARM_HASH} = \%parmhash;
     $self->{HASH_TIED} = 1;      $self->{PARM_CACHE} = {};
   
     # If the course opt hash and the user opt hash should be generated,      bless($self);
     # generate them  
     if ($self->{GENERATE_COURSE_USER_OPT}) {  
         my $uname=$ENV{'user.name'};  
         my $udom=$ENV{'user.domain'};  
         my $uhome=$ENV{'user.home'};  
         my $cid=$ENV{'request.course.id'};  
         my $chome=$ENV{'course.'.$cid.'.home'};  
         my ($cdom,$cnum)=split(/\_/,$cid);  
           
         my $userprefix=$uname.'_'.$udom.'_';  
                   
         my %courserdatas; my %useropt; my %courseopt;      return $self;
         unless ($uhome eq 'no_host') {   }
   
   sub generate_course_user_opt {
       my $self = shift;
       if ($self->{COURSE_USER_OPT_GENERATED}) { return; }
   
       my $uname=$ENV{'user.name'};
       my $udom=$ENV{'user.domain'};
       my $uhome=$ENV{'user.home'};
       my $cid=$ENV{'request.course.id'};
       my $chome=$ENV{'course.'.$cid.'.home'};
       my ($cdom,$cnum)=split(/\_/,$cid);
       
       my $userprefix=$uname.'_'.$udom.'_';
       
       my %courserdatas; my %useropt; my %courseopt; my %userrdatas;
       unless ($uhome eq 'no_host') { 
 # ------------------------------------------------- Get coursedata (if present)  # ------------------------------------------------- Get coursedata (if present)
             unless ((time-$courserdatas{$cid.'.last_cache'})<240) {   unless ((time-$courserdatas{$cid.'.last_cache'})<240) {
                 my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum.      my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum.
                                                  ':resourcedata',$chome);       ':resourcedata',$chome);
                 if ($reply!~/^error\:/) {      # Check for network failure
                     $courserdatas{$cid}=$reply;      if ( $reply =~ /no.such.host/i || $reply =~ /con_lost/i) {
                     $courserdatas{$cid.'.last_cache'}=time;   $self->{NETWORK_FAILURE} = 1;
                 }      } elsif ($reply!~/^error\:/) {
                 # check to see if network failed   $courserdatas{$cid}=$reply;
                 elsif ( $reply=~/no.such.host/i || $reply=~/con.*lost/i )   $courserdatas{$cid.'.last_cache'}=time;
                 {      }
                     $self->{NETWORK_FAILURE} = 1;   }
                 }   foreach (split(/\&/,$courserdatas{$cid})) {
             }      my ($name,$value)=split(/\=/,$_);
             foreach (split(/\&/,$courserdatas{$cid})) {      $courseopt{$userprefix.&Apache::lonnet::unescape($name)}=
                 my ($name,$value)=split(/\=/,$_);   &Apache::lonnet::unescape($value);
                 $courseopt{$userprefix.&Apache::lonnet::unescape($name)}=   }
                     &Apache::lonnet::unescape($value);  
             }  
 # --------------------------------------------------- Get userdata (if present)  # --------------------------------------------------- Get userdata (if present)
             unless ((time-$userrdatas{$uname.'___'.$udom.'.last_cache'})<240) {   unless ((time-$userrdatas{$uname.'___'.$udom.'.last_cache'})<240) {
                 my $reply=&Apache::lonnet::reply('dump:'.$udom.':'.$uname.':resourcedata',$uhome);      my $reply=&Apache::lonnet::reply('dump:'.$udom.':'.$uname.':resourcedata',$uhome);
                 if ($reply!~/^error\:/) {      if ($reply!~/^error\:/) {
                     $userrdatas{$uname.'___'.$udom}=$reply;   $userrdatas{$uname.'___'.$udom}=$reply;
                     $userrdatas{$uname.'___'.$udom.'.last_cache'}=time;   $userrdatas{$uname.'___'.$udom.'.last_cache'}=time;
                 }      }
                 # check to see if network failed      # check to see if network failed
                 elsif ( $reply=~/no.such.host/i || $reply=~/con.*lost/i )      elsif ( $reply=~/no.such.host/i || $reply=~/con.*lost/i )
                 {      {
                     $self->{NETWORK_FAILURE} = 1;   $self->{NETWORK_FAILURE} = 1;
                 }      }
             }   }
             foreach (split(/\&/,$userrdatas{$uname.'___'.$udom})) {   foreach (split(/\&/,$userrdatas{$uname.'___'.$udom})) {
                 my ($name,$value)=split(/\=/,$_);      my ($name,$value)=split(/\=/,$_);
                 $useropt{$userprefix.&Apache::lonnet::unescape($name)}=      $useropt{$userprefix.&Apache::lonnet::unescape($name)}=
                     &Apache::lonnet::unescape($value);   &Apache::lonnet::unescape($value);
             }   }
             $self->{COURSE_OPT} = \%courseopt;   $self->{COURSE_OPT} = \%courseopt;
             $self->{USER_OPT} = \%useropt;   $self->{USER_OPT} = \%useropt;
         }      }
     }     
   
     if ($self->{GENERATE_EMAIL_DISCUSS_STATUS}) {      $self->{COURSE_USER_OPT_GENERATED} = 1;
         my $cid=$ENV{'request.course.id'};  
         my ($cdom,$cnum)=split(/\_/,$cid);  
           
         my %emailstatus = &Apache::lonnet::dump('email_status');  
         my $logoutTime = $emailstatus{'logout'};  
         my $courseLeaveTime = $emailstatus{'logout_'.$ENV{'request.course.id'}};  
         $self->{LAST_CHECK} = ($courseLeaveTime > $logoutTime ?  
                                $courseLeaveTime : $logoutTime);  
         my %discussiontime = &Apache::lonnet::dump('discussiontimes',   
                                                    $cdom, $cnum);  
         my %feedback=();  
         my %error=();  
         my $keys = &Apache::lonnet::reply('keys:'.  
                                           $ENV{'user.domain'}.':'.  
                                           $ENV{'user.name'}.':nohist_email',  
                                           $ENV{'user.home'});  
   
         foreach my $msgid (split(/\&/, $keys)) {  
             $msgid=&Apache::lonnet::unescape($msgid);  
             my $plain=&Apache::lonnet::unescape(&Apache::lonnet::unescape($msgid));  
             if ($plain=~/(Error|Feedback) \[([^\]]+)\]/) {  
                 my ($what,$url)=($1,$2);  
                 my %status=  
                     &Apache::lonnet::get('email_status',[$msgid]);  
                 if ($status{$msgid}=~/^error\:/) {   
                     $status{$msgid}='';   
                 }  
                   
                 if (($status{$msgid} eq 'new') ||   
                     (!$status{$msgid})) {   
                     if ($what eq 'Error') {  
                         $error{$url}.=','.$msgid;   
                     } else {  
                         $feedback{$url}.=','.$msgid;  
                     }  
                 }  
             }  
         }  
           
         $self->{FEEDBACK} = \%feedback;  
         $self->{ERROR_MSG} = \%error; # what is this? JB  
         $self->{DISCUSSION_TIME} = \%discussiontime;  
         $self->{EMAIL_STATUS} = \%emailstatus;  
           
     }      
           
     bless($self);      return;
           
     return $self;  
 }  }
   
   sub generate_email_discuss_status {
       my $self = shift;
       if ($self->{EMAIL_DISCUSS_GENERATED}) { return; }
   
       my $cid=$ENV{'request.course.id'};
       my ($cdom,$cnum)=split(/\_/,$cid);
       
       my %emailstatus = &Apache::lonnet::dump('email_status');
       my $logoutTime = $emailstatus{'logout'};
       my $courseLeaveTime = $emailstatus{'logout_'.$ENV{'request.course.id'}};
       $self->{LAST_CHECK} = (($courseLeaveTime > $logoutTime) ?
      $courseLeaveTime : $logoutTime);
       my %discussiontime = &Apache::lonnet::dump('discussiontimes', 
          $cdom, $cnum);
       my %feedback=();
       my %error=();
       my $keys = &Apache::lonnet::reply('keys:'.
         $ENV{'user.domain'}.':'.
         $ENV{'user.name'}.':nohist_email',
         $ENV{'user.home'});
       
       foreach my $msgid (split(/\&/, $keys)) {
    $msgid=&Apache::lonnet::unescape($msgid);
    my $plain=&Apache::lonnet::unescape(&Apache::lonnet::unescape($msgid));
    if ($plain=~/(Error|Feedback) \[([^\]]+)\]/) {
       my ($what,$url)=($1,$2);
       my %status=
    &Apache::lonnet::get('email_status',[$msgid]);
       if ($status{$msgid}=~/^error\:/) { 
    $status{$msgid}=''; 
       }
       
       if (($status{$msgid} eq 'new') || 
    (!$status{$msgid})) { 
    if ($what eq 'Error') {
       $error{$url}.=','.$msgid; 
    } else {
       $feedback{$url}.=','.$msgid;
    }
       }
    }
       }
       
       $self->{FEEDBACK} = \%feedback;
       $self->{ERROR_MSG} = \%error; # what is this? JB
       $self->{DISCUSSION_TIME} = \%discussiontime;
       $self->{EMAIL_STATUS} = \%emailstatus;
       
       $self->{EMAIL_DISCUSS_GENERATED} = 1;
   }
   
   sub get_user_data {
       my $self = shift;
       if ($self->{RETRIEVED_USER_DATA}) { return; }
   
       # Retrieve performance data on problems
       my %student_data = Apache::lonnet::currentdump($ENV{'request.course.id'},
      $ENV{'user.domain'},
      $ENV{'user.name'});
       $self->{STUDENT_DATA} = \%student_data;
   
       $self->{RETRIEVED_USER_DATA} = 1;
   }
   
   # Internal function: Takes a key to look up in the nav hash and implements internal
   # memory caching of that key.
   sub navhash {
       my $self = shift; my $key = shift;
       return $self->{NAV_HASH}->{$key};
   }
   
   =pod
   
   =item * B<courseMapDefined>(): Returns true if the course map is defined, 
       false otherwise. Undefined course maps indicate an error somewhere in
       LON-CAPA, and you will not be able to proceed with using the navmap.
       See the B<NAV> screen for an example of using this.
   
   =cut
   
 # Checks to see if coursemap is defined, matching test in old lonnavmaps  # Checks to see if coursemap is defined, matching test in old lonnavmaps
 sub courseMapDefined {  sub courseMapDefined {
     my $self = shift;      my $self = shift;
     my $uri = &Apache::lonnet::clutter($ENV{'request.course.uri'});      my $uri = &Apache::lonnet::clutter($ENV{'request.course.uri'});
   
     my $firstres = $self->{NAV_HASH}->{"map_start_$uri"};      my $firstres = $self->navhash("map_start_$uri");
     my $lastres = $self->{NAV_HASH}->{"map_finish_$uri"};      my $lastres = $self->navhash("map_finish_$uri");
     return $firstres && $lastres;      return $firstres && $lastres;
 }  }
   
Line 1457  sub getIterator { Line 1822  sub getIterator {
 # unties the hash when done  # unties the hash when done
 sub untieHashes {  sub untieHashes {
     my $self = shift;      my $self = shift;
     untie %{$self->{NAV_HASH}} if ($self->{HASH_TIED});      untie %{$self->{NAV_HASH}};
     untie %{$self->{PARM_HASH}} if ($self->{HASH_TIED});      untie %{$self->{PARM_HASH}};
     $self->{HASH_TIED} = 0;  
 }  }
   
 # when the object is destroyed, be sure to untie all the hashes we tied.  # Private method: Does the given resource (as a symb string) have
 sub DESTROY {  
     my $self = shift;  
     $self->untieHashes();  
 }  
   
 # Private function: Does the given resource (as a symb string) have  
 # current discussion? Returns 0 if chat/mail data not extracted.  # current discussion? Returns 0 if chat/mail data not extracted.
 sub hasDiscussion {  sub hasDiscussion {
     my $self = shift;      my $self = shift;
     my $symb = shift;      my $symb = shift;
       
       $self->generate_email_discuss_status();
   
     if (!defined($self->{DISCUSSION_TIME})) { return 0; }      if (!defined($self->{DISCUSSION_TIME})) { return 0; }
   
       #return defined($self->{DISCUSSION_TIME}->{$symb});
     return $self->{DISCUSSION_TIME}->{$symb} >      return $self->{DISCUSSION_TIME}->{$symb} >
    $self->{LAST_CHECK};             $self->{LAST_CHECK};
 }  }
   
 # Private function: Does the given resource (as a symb string) have  # Private method: Does the given resource (as a symb string) have
 # current feedback? Returns the string in the feedback hash, which  # current feedback? Returns the string in the feedback hash, which
 # will be false if it does not exist.  # will be false if it does not exist.
 sub getFeedback {   sub getFeedback { 
     my $self = shift;      my $self = shift;
     my $symb = shift;      my $symb = shift;
   
       $self->generate_email_discuss_status();
   
     if (!defined($self->{FEEDBACK})) { return ""; }      if (!defined($self->{FEEDBACK})) { return ""; }
           
     return $self->{FEEDBACK}->{$symb};      return $self->{FEEDBACK}->{$symb};
 }  }
   
   # Private method: Get the errors for that resource (by source).
   sub getErrors { 
       my $self = shift;
       my $src = shift;
   
       $self->generate_email_discuss_status();
   
       if (!defined($self->{ERROR_MSG})) { return ""; }
       return $self->{ERROR_MSG}->{$src};
   }
   
 =pod  =pod
   
 =item * B<getById>(id): Based on the ID of the resource (1.1, 3.2, etc.), get a resource object for that resource. This method, or other methods that use it (as in the resource object) is the only proper way to obtain a resource object.  =item * B<getById>(id):
   
   Based on the ID of the resource (1.1, 3.2, etc.), get a resource
   object for that resource. This method, or other methods that use it
   (as in the resource object) is the only proper way to obtain a
   resource object.
   
   =item * B<getBySymb>(symb):
   
   Based on the symb of the resource, get a resource object for that
   resource. This is one of the proper ways to get a resource object.
   
   =item * B<getMapByMapPc>(map_pc):
   
   Based on the map_pc of the resource, get a resource object for
   the given map. This is one of the proper ways to get a resource object.
   
 =cut  =cut
   
 # The strategy here is to cache the resource objects, and only construct them  # The strategy here is to cache the resource objects, and only construct them
 # as we use them. The real point is to prevent reading any more from the tied  # as we use them. The real point is to prevent reading any more from the tied
 # hash then we have to, which should hopefully alleviate speed problems.  # hash then we have to, which should hopefully alleviate speed problems.
 # Caching is just an incidental detail I throw in because it makes sense.  
   
 sub getById {  sub getById {
     my $self = shift;      my $self = shift;
Line 1512  sub getById { Line 1901  sub getById {
     }      }
   
     # resource handles inserting itself into cache.      # resource handles inserting itself into cache.
     return Apache::lonnavmaps::resource->new($self, $id);      # Not clear why the quotes are necessary, but as of this
       # writing it doesn't work without them.
       return "Apache::lonnavmaps::resource"->new($self, $id);
   }
   
   sub getBySymb {
       my $self = shift;
       my $symb = shift;
       my ($mapUrl, $id, $filename) = split (/___/, $symb);
       my $map = $self->getResourceByUrl($mapUrl);
       return $self->getById($map->map_pc() . '.' . $id);
   }
   
   sub getByMapPc {
       my $self = shift;
       my $map_pc = shift;
       my $map_id = $self->{NAV_HASH}->{'map_id_' . $map_pc};
       $map_id = $self->{NAV_HASH}->{'ids_' . $map_id};
       return $self->getById($map_id);
 }  }
   
 =pod  =pod
   
 =item * B<firstResource>(): Returns a resource object reference corresponding to the first resource in the navmap.  =item * B<firstResource>():
   
   Returns a resource object reference corresponding to the first
   resource in the navmap.
   
 =cut  =cut
   
 sub firstResource {  sub firstResource {
     my $self = shift;      my $self = shift;
     my $firstResource = $self->{NAV_HASH}->{'map_start_' .      my $firstResource = $self->navhash('map_start_' .
                      &Apache::lonnet::clutter($ENV{'request.course.uri'})};                       &Apache::lonnet::clutter($ENV{'request.course.uri'}));
     return $self->getById($firstResource);      return $self->getById($firstResource);
 }  }
   
 =pod  =pod
   
 =item * B<finishResource>(): Returns a resource object reference corresponding to the last resource in the navmap.  =item * B<finishResource>():
   
   Returns a resource object reference corresponding to the last resource
   in the navmap.
   
 =cut  =cut
   
 sub finishResource {  sub finishResource {
     my $self = shift;      my $self = shift;
     my $firstResource = $self->{NAV_HASH}->{'map_finish_' .      my $firstResource = $self->navhash('map_finish_' .
                      &Apache::lonnet::clutter($ENV{'request.course.uri'})};                       &Apache::lonnet::clutter($ENV{'request.course.uri'}));
     return $self->getById($firstResource);      return $self->getById($firstResource);
 }  }
   
 # -------------------------------------------- Figure out a cascading parameter  # Parmval reads the parm hash and cascades the lookups. parmval_real does
 #  # the actual lookup; parmval caches the results.
 # For this function to work  
 #  
 # * parmhash needs to be tied  
 # * courseopt and useropt need to be initialized for this user and course  
 #  
   
 sub parmval {  sub parmval {
     my $self = shift;      my $self = shift;
     my ($what,$symb)=@_;      my ($what,$symb)=@_;
       my $hashkey = $what."|||".$symb;
   
       if (defined($self->{PARM_CACHE}->{$hashkey})) {
           return $self->{PARM_CACHE}->{$hashkey};
       }
   
       my $result = $self->parmval_real($what, $symb);
       $self->{PARM_CACHE}->{$hashkey} = $result;
       return $result;
   }
   
   sub parmval_real {
       my $self = shift;
       my ($what,$symb,$recurse) = @_;
   
       # Make sure the {USER_OPT} and {COURSE_OPT} hashes are populated
       $self->generate_course_user_opt();
   
     my $cid=$ENV{'request.course.id'};      my $cid=$ENV{'request.course.id'};
     my $csec=$ENV{'request.course.sec'};      my $csec=$ENV{'request.course.sec'};
     my $uname=$ENV{'user.name'};      my $uname=$ENV{'user.name'};
Line 1618  sub parmval { Line 2043  sub parmval {
     my ($space,@qualifier)=split(/\./,$rwhat);      my ($space,@qualifier)=split(/\./,$rwhat);
     my $qualifier=join('.',@qualifier);      my $qualifier=join('.',@qualifier);
     unless ($space eq '0') {      unless ($space eq '0') {
         my ($part,$id)=split(/\_/,$space);   my @parts=split(/_/,$space);
         if ($id) {   my $id=pop(@parts);
             my $partgeneral=$self->parmval($part.".$qualifier",$symb);   my $part=join('_',@parts);
             if (defined($partgeneral)) { return $partgeneral; }   if ($part eq '') { $part='0'; }
         } else {   my $partgeneral=$self->parmval($part.".$qualifier",$symb,1);
             my $resourcegeneral=$self->parmval("0.$qualifier",$symb);   if (defined($partgeneral)) { return $partgeneral; }
             if (defined($resourcegeneral)) { return $resourcegeneral; }      }
       if ($recurse) { return undef; }
       my $pack_def=&Apache::lonnet::packages_tab_default($fn,'resource.'.$what);
       if (defined($pack_def)) { return $pack_def; }
       return '';
   }
   
   =pod
   
   =item * B<getResourceByUrl>(url):
   
   Retrieves a resource object by URL of the resource. If passed a
   resource object, it will simply return it, so it is safe to use this
   method in code like "$res = $navmap->getResourceByUrl($res)", if
   you're not sure if $res is already an object, or just a URL. If the
   resource appears multiple times in the course, only the first instance
   will be returned. As a result, this is probably useful only for maps.
   
   =item * B<retrieveResources>(map, filterFunc, recursive, bailout):
   
   The map is a specification of a map to retreive the resources from,
   either as a url or as an object. The filterFunc is a reference to a
   function that takes a resource object as its one argument and returns
   true if the resource should be included, or false if it should not
   be. If recursive is true, the map will be recursively examined,
   otherwise it will not be. If bailout is true, the function will return
   as soon as it finds a resource, if false it will finish. By default,
   the map is the top-level map of the course, filterFunc is a function
   that always returns 1, recursive is true, bailout is false. The
   resources will be returned in a list containing the resource objects
   for the corresponding resources, with B<no structure information> in
   the list; regardless of branching, recursion, etc., it will be a flat
   list.
   
   Thus, this is suitable for cases where you don't want the structure,
   just a list of all resources. It is also suitable for finding out how
   many resources match a given description; for this use, if all you
   want to know is if I<any> resources match the description, the bailout
   parameter will allow you to avoid potentially expensive enumeration of
   all matching resources.
   
   =item * B<hasResources>(map, filterFunc, recursive):
   
   Convience method for
   
    scalar(retrieveResources($map, $filterFunc, $recursive, 1)) > 0
   
   which will tell whether the map has resources matching the description
   in the filter function.
   
   =cut
   
   sub getResourceByUrl {
       my $self = shift;
       my $resUrl = shift;
   
       if (ref($resUrl)) { return $resUrl; }
   
       $resUrl = &Apache::lonnet::clutter($resUrl);
       my $resId = $self->{NAV_HASH}->{'ids_' . $resUrl};
       if ($resId =~ /,/) {
           $resId = (split (/,/, $resId))[0];
       }
       if (!$resId) { return ''; }
       return $self->getById($resId);
   }
   
   sub retrieveResources {
       my $self = shift;
       my $map = shift;
       my $filterFunc = shift;
       if (!defined ($filterFunc)) {
           $filterFunc = sub {return 1;};
       }
       my $recursive = shift;
       if (!defined($recursive)) { $recursive = 1; }
       my $bailout = shift;
       if (!defined($bailout)) { $bailout = 0; }
   
       # Create the necessary iterator.
       if (!ref($map)) { # assume it's a url of a map.
           $map = $self->getResourceByUrl($map);
       }
   
       # If nothing was passed, assume top-level map
       if (!$map) {
    $map = $self->getById('0.0');
       }
   
       # Check the map's validity.
       if (!$map->is_map()) {
           # Oh, to throw an exception.... how I'd love that!
           return ();
       }
   
       # Get an iterator.
       my $it = $self->getIterator($map->map_start(), $map->map_finish(),
                                   undef, $recursive);
   
       my @resources = ();
   
       # Run down the iterator and collect the resources.
       my $curRes;
   
       while ($curRes = $it->next()) {
           if (ref($curRes)) {
               if (!&$filterFunc($curRes)) {
                   next;
               }
   
               push @resources, $curRes;
   
               if ($bailout) {
                   return @resources;
               }
         }          }
   
     }      }
     return '';  
       return @resources;
 }  }
   
   sub hasResource {
       my $self = shift;
       my $map = shift;
       my $filterFunc = shift;
       my $recursive = shift;
       
       return scalar($self->retrieveResources($map, $filterFunc, $recursive, 1)) > 0;
   }
   
 1;  1;
   
 package Apache::lonnavmaps::iterator;  package Apache::lonnavmaps::iterator;
   
 # This package must precede "navmap" because "navmap" uses it. In  
 # order to keep the documentation order straight, the iterator is documented  
 # after the navmap object.  
   
 =pod  =pod
   
 =back  =back
   
 =head1 navmap Iterator  =head1 Object: navmap Iterator
   
 An I<iterator> encapsulates the logic required to traverse a data structure. navmap uses an iterator to traverse the course map according to the criteria you wish to use.  An I<iterator> encapsulates the logic required to traverse a data
   structure. navmap uses an iterator to traverse the course map
 To obtain an iterator, call the B<getIterator>() function of a B<navmap> object. (Do not instantiate Apache::lonnavmaps::iterator directly.) This will return a reference to the iterator:  according to the criteria you wish to use.
   
   To obtain an iterator, call the B<getIterator>() function of a
   B<navmap> object. (Do not instantiate Apache::lonnavmaps::iterator
   directly.) This will return a reference to the iterator:
   
 C<my $resourceIterator = $navmap-E<gt>getIterator();>  C<my $resourceIterator = $navmap-E<gt>getIterator();>
   
Line 1659  getIterator behaves as follows: Line 2208  getIterator behaves as follows:
   
 =over 4  =over 4
   
 =item B<getIterator>(nav_map, firstResource, finishResource, filterHash, condition): All parameters are optional. firstResource is a resource reference corresponding to where the iterator should start. It defaults to navmap->firstResource() for the corresponding nav map. finishResource corresponds to where you want the iterator to end, defaulting to navmap->finishResource(). It is your responsibility to ensure that the iterator will actually get there. filterHash is a hash used as a set containing strings representing the resource IDs, defaulting to empty. Condition is a 1 or 0 that sets what to do with the filter hash: If a 0, then only resource that exist IN the filterHash will be recursed on. If it is a 1, only resources NOT in the filterHash will be recursed on. Defaults to 0, which is to say, do not recurse unless explicitly asked to.  =item * B<getIterator>(firstResource, finishResource, filterHash, condition, forceTop, returnTopMap):
   
 Thus, by default, all resources will be shown. Change the condition to a 1 without changing the hash, and only the top level of the map will be shown. Changing the condition to 1 and including some values in the hash will allow you to selectively examine parts of the navmap, while leaving it on 0 and adding things to the hash will allow you to selectively ignore parts of the nav map. See the handler code for examples.  
   
 The iterator will return either a reference to a resource object, or a token representing something in the map, such as the beginning of a new branch. The possible tokens are:  All parameters are optional. firstResource is a resource reference
   corresponding to where the iterator should start. It defaults to
   navmap->firstResource() for the corresponding nav map. finishResource
   corresponds to where you want the iterator to end, defaulting to
   navmap->finishResource(). filterHash is a hash used as a set
   containing strings representing the resource IDs, defaulting to
   empty. Condition is a 1 or 0 that sets what to do with the filter
   hash: If a 0, then only resources that exist IN the filterHash will be
   recursed on. If it is a 1, only resources NOT in the filterHash will
   be recursed on. Defaults to 0. forceTop is a boolean value. If it is
   false (default), the iterator will only return the first level of map
   that is not just a single, 'redirecting' map. If true, the iterator
   will return all information, starting with the top-level map,
   regardless of content. returnTopMap, if true (default false), will
   cause the iterator to return the top-level map object (resource 0.0)
   before anything else.
   
   Thus, by default, only top-level resources will be shown. Change the
   condition to a 1 without changing the hash, and all resources will be
   shown. Changing the condition to 1 and including some values in the
   hash will allow you to selectively suppress parts of the navmap, while
   leaving it on 0 and adding things to the hash will allow you to
   selectively add parts of the nav map. See the handler code for
   examples.
   
   The iterator will return either a reference to a resource object, or a
   token representing something in the map, such as the beginning of a
   new branch. The possible tokens are:
   
 =over 4  =over 4
   
 =item * some list of tokens here  =item * B<END_ITERATOR>:
   
   The iterator has returned all that it's going to. Further calls to the
   iterator will just produce more of these. This is a "false" value, and
   is the only false value the iterator which will be returned, so it can
   be used as a loop sentinel.
   
   =item * B<BEGIN_MAP>:
   
   A new map is being recursed into. This is returned I<after> the map
   resource itself is returned.
   
   =item * B<END_MAP>:
   
   The map is now done.
   
   =item * B<BEGIN_BRANCH>:
   
   A branch is now starting. The next resource returned will be the first
   in that branch.
   
   =item * B<END_BRANCH>:
   
   The branch is now done.
   
 =back  =back
   
 The tokens are retreivable via methods on the iterator object, i.e., $iterator->END_NAV_MAP. (Perl will automatically optimize these into constants.  The tokens are retreivable via methods on the iterator object, i.e.,
   $iterator->END_MAP.
   
   Maps can contain empty resources. The iterator will automatically skip
   over such resources, but will still treat the structure
   correctly. Thus, a complicated map with several branches, but
   consisting entirely of empty resources except for one beginning or
   ending resource, will cause a lot of BRANCH_STARTs and BRANCH_ENDs,
   but only one resource will be returned.
   
   =head2 Normal Usage
   
   Normal usage of the iterator object is to do the following:
   
    my $it = $navmap->getIterator([your params here]);
    my $curRes;
    while ($curRes = $it->next()) {
      [your logic here]
    }
   
   Note that inside of the loop, it's frequently useful to check if
   "$curRes" is a reference or not with the reference function; only
   resource objects will be references, and any non-references will 
   be the tokens described above.
   
   Also note there is some old code floating around that trys to track
   the depth of the iterator to see when it's done; do not copy that 
   code. It is difficult to get right and harder to understand then
   this. They should be migrated to this new style.
   
   =back
   
 =cut  =cut
   
 # Here are the tokens for the iterator:  # Here are the tokens for the iterator:
   
 sub END_NAV_MAP { return 0; }  # Represents end of entire nav map  sub END_ITERATOR { return 0; }
 sub BEGIN_MAP { return 1; }    # begining of a new map  sub BEGIN_MAP { return 1; }    # begining of a new map
 sub END_MAP { return 2; }      # end of the map  sub END_MAP { return 2; }      # end of the map
 sub BEGIN_BRANCH { return 3; } # beginning of a branch  sub BEGIN_BRANCH { return 3; } # beginning of a branch
 sub END_BRANCH { return 4; }   # end of a branch  sub END_BRANCH { return 4; }   # end of a branch
   sub FORWARD { return 1; }      # go forward
   sub BACKWARD { return 2; }
   
 # Params: nav map, start resource, end resource, filter, condition,   sub min {
 # already seen hash ref      (my $a, my $b) = @_;
       if ($a < $b) { return $a; } else { return $b; }
   }
   
 sub new {  sub new {
     # magic invocation to create a class instance      # magic invocation to create a class instance
Line 1713  sub new { Line 2344  sub new {
     if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };      if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };
     $self->{CONDITION} = shift;      $self->{CONDITION} = shift;
   
     # Flag: Have we started yet? If not, the first action is to return BEGIN_MAP.      # Do we want to automatically follow "redirection" maps?
       $self->{FORCE_TOP} = shift;
   
       # Do we want to return the top-level map object (resource 0.0)?
       $self->{RETURN_0} = shift;
       # have we done that yet?
       $self->{HAVE_RETURNED_0} = 0;
   
       # Now, we need to pre-process the map, by walking forward and backward
       # over the parts of the map we're going to look at.
   
       # The processing steps are exactly the same, except for a few small 
       # changes, so I bundle those up in the following list of two elements:
       # (direction_to_iterate, VAL_name, next_resource_method_to_call,
       # first_resource).
       # This prevents writing nearly-identical code twice.
       my @iterations = ( [FORWARD(), 'TOP_DOWN_VAL', 'getNext', 
                           'FIRST_RESOURCE'],
                          [BACKWARD(), 'BOT_UP_VAL', 'getPrevious', 
                           'FINISH_RESOURCE'] );
   
       my $maxDepth = 0; # tracks max depth
   
       # If there is only one resource in this map, and it's a map, we
       # want to remember that, so the user can ask for the first map
       # that isn't just a redirector.
       my $resource; my $resourceCount = 0;
   
       # Documentation on this algorithm can be found in the CVS repository at 
       # /docs/lonnavdocs; these "**#**" markers correspond to documentation
       # in that file.
       # **1**
   
       foreach my $pass (@iterations) {
           my $direction = $pass->[0];
           my $valName = $pass->[1];
           my $nextResourceMethod = $pass->[2];
           my $firstResourceName = $pass->[3];
   
           my $iterator = Apache::lonnavmaps::DFSiterator->new($self->{NAV_MAP}, 
                                                               $self->{FIRST_RESOURCE},
                                                               $self->{FINISH_RESOURCE},
                                                               {}, undef, 0, $direction);
       
           # prime the recursion
           $self->{$firstResourceName}->{DATA}->{$valName} = 0;
    $iterator->next();
           my $curRes = $iterator->next();
    my $depth = 1;
           while ($depth > 0) {
       if ($curRes == $iterator->BEGIN_MAP()) { $depth++; }
       if ($curRes == $iterator->END_MAP()) { $depth--; }
   
               if (ref($curRes)) {
                   # If there's only one resource, this will save it
                   # we have to filter empty resources from consideration here,
                   # or even "empty", redirecting maps have two (start & finish)
                   # or three (start, finish, plus redirector)
                   if($direction == FORWARD && $curRes->src()) { 
                       $resource = $curRes; $resourceCount++; 
                   }
                   my $resultingVal = $curRes->{DATA}->{$valName};
                   my $nextResources = $curRes->$nextResourceMethod();
                   my $nextCount = scalar(@{$nextResources});
   
                   if ($nextCount == 1) { # **3**
                       my $current = $nextResources->[0]->{DATA}->{$valName} || 999999999;
                       $nextResources->[0]->{DATA}->{$valName} = min($resultingVal, $current);
                   }
                   
                   if ($nextCount > 1) { # **4**
                       foreach my $res (@{$nextResources}) {
                           my $current = $res->{DATA}->{$valName} || 999999999;
                           $res->{DATA}->{$valName} = min($current, $resultingVal + 1);
                       }
                   }
               }
               
               # Assign the final val (**2**)
               if (ref($curRes) && $direction == BACKWARD()) {
                   my $finalDepth = min($curRes->{DATA}->{TOP_DOWN_VAL},
                                        $curRes->{DATA}->{BOT_UP_VAL});
                   
                   $curRes->{DATA}->{DISPLAY_DEPTH} = $finalDepth;
                   if ($finalDepth > $maxDepth) {$maxDepth = $finalDepth;}
               }
   
       $curRes = $iterator->next();
           }
       }
   
       # Check: Was this only one resource, a map?
       if ($resourceCount == 1 && $resource->is_map() && !$self->{FORCE_TOP}) { 
           my $firstResource = $resource->map_start();
           my $finishResource = $resource->map_finish();
           return 
               Apache::lonnavmaps::iterator->new($self->{NAV_MAP}, $firstResource,
                                                 $finishResource, $self->{FILTER},
                                                 $self->{ALREADY_SEEN}, 
                                                 $self->{CONDITION}, 0);
           
       }
   
       # Set up some bookkeeping information.
       $self->{CURRENT_DEPTH} = 0;
       $self->{MAX_DEPTH} = $maxDepth;
       $self->{STACK} = [];
       $self->{RECURSIVE_ITERATOR_FLAG} = 0;
       $self->{FINISHED} = 0; # When true, the iterator has finished
   
       for (my $i = 0; $i <= $self->{MAX_DEPTH}; $i++) {
           push @{$self->{STACK}}, [];
       }
   
       # Prime the recursion w/ the first resource **5**
       push @{$self->{STACK}->[0]}, $self->{FIRST_RESOURCE};
       $self->{ALREADY_SEEN}->{$self->{FIRST_RESOURCE}->{ID}} = 1;
   
       bless ($self);
   
       return $self;
   }
   
   sub next {
       my $self = shift;
   
       if ($self->{FINISHED}) {
    return END_ITERATOR();
       }
   
       # If we want to return the top-level map object, and haven't yet,
       # do so.
       if ($self->{RETURN_0} && !$self->{HAVE_RETURNED_0}) {
           $self->{HAVE_RETURNED_0} = 1;
           return $self->{NAV_MAP}->getById('0.0');
       }
   
       if ($self->{RECURSIVE_ITERATOR_FLAG}) {
           # grab the next from the recursive iterator 
           my $next = $self->{RECURSIVE_ITERATOR}->next();
   
           # is it a begin or end map? If so, update the depth
           if ($next == BEGIN_MAP() ) { $self->{RECURSIVE_DEPTH}++; }
           if ($next == END_MAP() ) { $self->{RECURSIVE_DEPTH}--; }
   
           # Are we back at depth 0? If so, stop recursing
           if ($self->{RECURSIVE_DEPTH} == 0) {
               $self->{RECURSIVE_ITERATOR_FLAG} = 0;
           }
   
           return $next;
       }
   
       if (defined($self->{FORCE_NEXT})) {
           my $tmp = $self->{FORCE_NEXT};
           $self->{FORCE_NEXT} = undef;
           return $tmp;
       }
   
       # Have we not yet begun? If not, return BEGIN_MAP and
       # remember we've started.
       if ( !$self->{STARTED} ) { 
           $self->{STARTED} = 1;
           return $self->BEGIN_MAP();
       }
   
       # Here's the guts of the iterator.
       
       # Find the next resource, if any.
       my $found = 0;
       my $i = $self->{MAX_DEPTH};
       my $newDepth;
       my $here;
       while ( $i >= 0 && !$found ) {
           if ( scalar(@{$self->{STACK}->[$i]}) > 0 ) { # **6**
               $here = pop @{$self->{STACK}->[$i]}; # **7**
               $found = 1;
               $newDepth = $i;
           }
           $i--;
       }
   
       # If we still didn't find anything, we're done.
       if ( !$found ) {
           # We need to get back down to the correct branch depth
           if ( $self->{CURRENT_DEPTH} > 0 ) {
               $self->{CURRENT_DEPTH}--;
               return END_BRANCH();
           } else {
       $self->{FINISHED} = 1;
               return END_MAP();
           }
       }
   
       # If this is not a resource, it must be an END_BRANCH marker we want
       # to return directly.
       if (!ref($here)) { # **8**
           if ($here == END_BRANCH()) { # paranoia, in case of later extension
               $self->{CURRENT_DEPTH}--;
               return $here;
           }
       }
   
       # Otherwise, it is a resource and it's safe to store in $self->{HERE}
       $self->{HERE} = $here;
   
       # Get to the right level
       if ( $self->{CURRENT_DEPTH} > $newDepth ) {
           push @{$self->{STACK}->[$newDepth]}, $here;
           $self->{CURRENT_DEPTH}--;
           return END_BRANCH();
       }
       if ( $self->{CURRENT_DEPTH} < $newDepth) {
           push @{$self->{STACK}->[$newDepth]}, $here;
           $self->{CURRENT_DEPTH}++;
           return BEGIN_BRANCH();
       }
   
       # If we made it here, we have the next resource, and we're at the
       # right branch level. So let's examine the resource for where
       # we can get to from here.
   
       # So we need to look at all the resources we can get to from here,
       # categorize them if we haven't seen them, remember if we have a new
       my $nextUnfiltered = $here->getNext();
       my $maxDepthAdded = -1;
       
       for (@$nextUnfiltered) {
           if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) {
               my $depth = $_->{DATA}->{DISPLAY_DEPTH};
               push @{$self->{STACK}->[$depth]}, $_;
               $self->{ALREADY_SEEN}->{$_->{ID}} = 1;
               if ($maxDepthAdded < $depth) { $maxDepthAdded = $depth; }
           }
       }
   
       # Is this the end of a branch? If so, all of the resources examined above
       # led to lower levels then the one we are currently at, so we push a END_BRANCH
       # marker onto the stack so we don't forget.
       # Example: For the usual A(BC)(DE)F case, when the iterator goes down the
       # BC branch and gets to C, it will see F as the only next resource, but it's
       # one level lower. Thus, this is the end of the branch, since there are no
       # more resources added to this level or above.
       # We don't do this if the examined resource is the finish resource,
       # because the condition given above is true, but the "END_MAP" will
       # take care of things and we should already be at depth 0.
       my $isEndOfBranch = $maxDepthAdded < $self->{CURRENT_DEPTH};
       if ($isEndOfBranch && $here != $self->{FINISH_RESOURCE}) { # **9**
           push @{$self->{STACK}->[$self->{CURRENT_DEPTH}]}, END_BRANCH();
       }
   
       # That ends the main iterator logic. Now, do we want to recurse
       # down this map (if this resource is a map)?
       if ($self->{HERE}->is_map() &&
           (defined($self->{FILTER}->{$self->{HERE}->map_pc()}) xor $self->{CONDITION})) {
           $self->{RECURSIVE_ITERATOR_FLAG} = 1;
           my $firstResource = $self->{HERE}->map_start();
           my $finishResource = $self->{HERE}->map_finish();
   
           $self->{RECURSIVE_ITERATOR} = 
               Apache::lonnavmaps::iterator->new($self->{NAV_MAP}, $firstResource,
                                                 $finishResource, $self->{FILTER},
                                                 $self->{ALREADY_SEEN}, $self->{CONDITION});
       }
   
       # If this is a blank resource, don't actually return it.
       # Should you ever find you need it, make sure to add an option to the code
       #  that you can use; other things depend on this behavior.
       my $browsePriv = $self->{HERE}->browsePriv();
       if (!$self->{HERE}->src() || 
           (!($browsePriv eq 'F') && !($browsePriv eq '2')) ) {
           return $self->next();
       }
   
       return $self->{HERE};
   
   }
   
   =pod
   
   The other method available on the iterator is B<getStack>, which
   returns an array populated with the current 'stack' of maps, as
   references to the resource objects. Example: This is useful when
   making the navigation map, as we need to check whether we are under a
   page map to see if we need to link directly to the resource, or to the
   page. The first elements in the array will correspond to the top of
   the stack (most inclusive map).
   
   =cut
   
   sub getStack {
       my $self=shift;
   
       my @stack;
   
       $self->populateStack(\@stack);
   
       return \@stack;
   }
   
   # Private method: Calls the iterators recursively to populate the stack.
   sub populateStack {
       my $self=shift;
       my $stack = shift;
   
       push @$stack, $self->{HERE} if ($self->{HERE});
   
       if ($self->{RECURSIVE_ITERATOR_FLAG}) {
           $self->{RECURSIVE_ITERATOR}->populateStack($stack);
       }
   }
   
   1;
   
   package Apache::lonnavmaps::DFSiterator;
   
   # Not documented in the perldoc: This is a simple iterator that just walks
   #  through the nav map and presents the resources in a depth-first search
   #  fashion, ignorant of conditionals, randomized resources, etc. It presents
   #  BEGIN_MAP and END_MAP, but does not understand branches at all. It is
   #  useful for pre-processing of some kind, and is in fact used by the main
   #  iterator that way, but that's about it.
   # One could imagine merging this into the init routine of the main iterator,
   #  but this might as well be left seperate, since it is possible some other
   #  use might be found for it. - Jeremy
   
   # Unlike the main iterator, this DOES return all resources, even blank ones.
   #  The main iterator needs them to correctly preprocess the map.
   
   sub BEGIN_MAP { return 1; }    # begining of a new map
   sub END_MAP { return 2; }      # end of the map
   sub FORWARD { return 1; }      # go forward
   sub BACKWARD { return 2; }
   
   # Params: Nav map ref, first resource id/ref, finish resource id/ref,
   #         filter hash ref (or undef), already seen hash or undef, condition
   #         (as in main iterator), direction FORWARD or BACKWARD (undef->forward).
   sub new {
       # magic invocation to create a class instance
       my $proto = shift;
       my $class = ref($proto) || $proto;
       my $self = {};
   
       $self->{NAV_MAP} = shift;
       return undef unless ($self->{NAV_MAP});
   
       $self->{FIRST_RESOURCE} = shift || $self->{NAV_MAP}->firstResource();
       $self->{FINISH_RESOURCE} = shift || $self->{NAV_MAP}->finishResource();
   
       # If the given resources are just the ID of the resource, get the
       # objects
       if (!ref($self->{FIRST_RESOURCE})) { $self->{FIRST_RESOURCE} = 
                $self->{NAV_MAP}->getById($self->{FIRST_RESOURCE}); }
       if (!ref($self->{FINISH_RESOURCE})) { $self->{FINISH_RESOURCE} = 
                $self->{NAV_MAP}->getById($self->{FINISH_RESOURCE}); }
   
       $self->{FILTER} = shift;
   
       # A hash, used as a set, of resource already seen
       $self->{ALREADY_SEEN} = shift;
        if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };
       $self->{CONDITION} = shift;
       $self->{DIRECTION} = shift || FORWARD();
   
       # Flag: Have we started yet?
     $self->{STARTED} = 0;      $self->{STARTED} = 0;
   
     # Should we continue calling the recursive iterator, if any?      # Should we continue calling the recursive iterator, if any?
Line 1727  sub new { Line 2722  sub new {
     $self->{RECURSIVE_DEPTH} = 0;      $self->{RECURSIVE_DEPTH} = 0;
   
     # For keeping track of our branches, we maintain our own stack      # For keeping track of our branches, we maintain our own stack
     $self->{BRANCH_STACK} = [];      $self->{STACK} = [];
     # If the size shrinks, we exhausted a branch  
     $self->{BRANCH_STACK_SIZE} = 0;  
     $self->{BRANCH_DEPTH} = 0;  
   
     # For returning two things in a forced sequence  
     $self->{FORCE_NEXT} = undef;  
   
     # Start with the first resource      # Start with the first resource
     push @{$self->{BRANCH_STACK}}, $self->{FIRST_RESOURCE};      if ($self->{DIRECTION} == FORWARD) {
     $self->{BRANCH_STACK_SIZE} = 1;          push @{$self->{STACK}}, $self->{FIRST_RESOURCE};
       } else {
           push @{$self->{STACK}}, $self->{FINISH_RESOURCE};
       }
   
     bless($self);      bless($self);
     return $self;      return $self;
 }  }
   
 # Note... this function is *touchy*. I strongly recommend tracing  
 # through it with the debugger a few times on a non-trivial map before  
 # modifying it. Order is *everything*.  
 sub next {  sub next {
     my $self = shift;      my $self = shift;
           
     # Iterator logic goes here  
   
     # Is this return value pre-determined?  
     if (defined($self->{FORCE_NEXT})) {  
         my $tmp = $self->{FORCE_NEXT};  
         $self->{FORCE_NEXT} = undef;  
         return $tmp;  
     }  
   
     # Are we using a recursive iterator? If so, pull from that and      # Are we using a recursive iterator? If so, pull from that and
     # watch the depth; we want to resume our level at the correct time.      # watch the depth; we want to resume our level at the correct time.
     if ($self->{RECURSIVE_ITERATOR_FLAG})      if ($self->{RECURSIVE_ITERATOR_FLAG}) {
     {  
         # grab the next from the recursive iterator          # grab the next from the recursive iterator
         my $next = $self->{RECURSIVE_ITERATOR}->next();          my $next = $self->{RECURSIVE_ITERATOR}->next();
                   
Line 1778  sub next { Line 2757  sub next {
     }      }
   
     # Is there a current resource to grab? If not, then return      # Is there a current resource to grab? If not, then return
     # END_BRANCH and END_MAP in succession.      # END_MAP, which will end the iterator.
     if (scalar(@{$self->{BRANCH_STACK}}) == 0) {      if (scalar(@{$self->{STACK}}) == 0) {
         if ($self->{BRANCH_DEPTH} > 0) {          return $self->END_MAP();
             $self->{FORCE_NEXT} = $self->END_MAP();  
             $self->{BRANCH_DEPTH}--;  
             return $self->END_BRANCH();  
         } else {  
             return $self->END_MAP();  
         }  
     }      }
   
     # Have we not yet begun? If not, return BEGIN_MAP and       # Have we not yet begun? If not, return BEGIN_MAP and 
Line 1796  sub next { Line 2769  sub next {
         return $self->BEGIN_MAP;          return $self->BEGIN_MAP;
     }      }
   
     # Did the branch stack shrink since last run? If so,  
     # we exhausted a branch last time, therefore, we're about  
     # to start a new one. (We know because we already checked to see  
     # if the stack was empty.)  
     if ( scalar (@{$self->{BRANCH_STACK}}) < $self->{BRANCH_STACK_SIZE}) {  
         $self->{BRANCH_STACK_SIZE} = scalar(@{$self->{BRANCH_STACK}});  
         $self->{BRANCH_DEPTH}++;  
         return $self->BEGIN_BRANCH();  
     }  
   
     # Remember the size for comparision next time.  
     $self->{BRANCH_STACK_SIZE} = scalar(@{$self->{BRANCH_STACK}});  
   
     # If the next resource we mean to return is going to need  
     # a lower branch level, terminate branches until we get   
     # there.  
   
     # Get the next resource in the branch      # Get the next resource in the branch
     $self->{HERE} = pop @{$self->{BRANCH_STACK}};      $self->{HERE} = pop @{$self->{STACK}};
   
     # Are we at the right depth? If not, close a branch and return      # remember that we've seen this, so we don't return it again later
     # the current resource onto the branch stack  
     if (defined($self->{HERE}->{DATA}->{ITERATOR_DEPTH})  
         && $self->{HERE}->{DATA}->{ITERATOR_DEPTH} <  
         $self->{BRANCH_DEPTH} ) {  
         $self->{BRANCH_DEPTH}--;  
         # return it so we can pick it up eventually  
         push @{$self->{BRANCH_STACK}}, $self->{HERE};  
         return $self->END_BRANCH();  
     }  
   
     # We always return it after this point and never before  
     # (proof: look at just the return statements), so we  
     # remember that we've seen this.  
     $self->{ALREADY_SEEN}->{$self->{HERE}->{ID}} = 1;      $self->{ALREADY_SEEN}->{$self->{HERE}->{ID}} = 1;
           
     # Are we at the utter end? If so, return the END_NAV_MAP marker.  
     if ($self->{HERE} == $self->{NAV_MAP}->finishResource() ) {  
         $self->{FORCE_NEXT} = $self->END_NAV_MAP;  
         return $self->{HERE};  
     }  
       
     # Get the next possible resources      # Get the next possible resources
     my $nextUnfiltered = $self->{HERE}->getNext();      my $nextUnfiltered;
       if ($self->{DIRECTION} == FORWARD()) {
           $nextUnfiltered = $self->{HERE}->getNext();
       } else {
           $nextUnfiltered = $self->{HERE}->getPrevious();
       }
     my $next = [];      my $next = [];
   
     # filter the next possibilities to remove things we've       # filter the next possibilities to remove things we've 
     # already seen. Also, remember what branch depth they should      # already seen.
     # be displayed at, since there's no other reliable way to tell.  
     foreach (@$nextUnfiltered) {      foreach (@$nextUnfiltered) {
         if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) {          if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) {
             push @$next, $_;              push @$next, $_;
             $_->{DATA}->{ITERATOR_DEPTH} =   
                 $self->{BRANCH_DEPTH} + 1;  
         }          }
     }      }
   
     # Handle branch cases:  
     # Nothing is available next: BRANCH_END  
     # 1 thing next: standard non-branch  
     # 2+ things next: have some branches  
     my $nextCount = scalar(@$next);  
     if ($nextCount == 0) {  
         # Return this and on the next run, close the branch up if we're   
         # in a branch  
         if ($self->{BRANCH_DEPTH} > 0 ) {  
             $self->{FORCE_NEXT} = $self->END_BRANCH();  
             $self->{BRANCH_DEPTH}--;  
         }  
         return $self->{HERE};  
     }  
       
     while (@$next) {      while (@$next) {
         # copy the next possibilities over to the branch stack          # copy the next possibilities over to the stack
         # in the right order          push @{$self->{STACK}}, shift @$next;
         push @{$self->{BRANCH_STACK}}, shift @$next;  
     }  
   
     if ($nextCount >= 2) {  
         $self->{FORCE_NEXT} = $self->BEGIN_BRANCH();  
         $self->{BRANCH_DEPTH}++;  
         return $self->{HERE};   
     }      }
   
     # If this is a map and we want to recurse down it... (not filtered out)      # If this is a map and we want to recurse down it... (not filtered out)
Line 1887  sub next { Line 2804  sub next {
         my $firstResource = $self->{HERE}->map_start();          my $firstResource = $self->{HERE}->map_start();
         my $finishResource = $self->{HERE}->map_finish();          my $finishResource = $self->{HERE}->map_finish();
   
         # Odd perl syntax here; $self->new allows one to create a new iterator  
         # can't figure out how to ref this package directly correctly  
         # isn't MAIN::new, __PACKAGE__::new or Apache::lonnavmaps::iterator->new  
         $self->{RECURSIVE_ITERATOR} =          $self->{RECURSIVE_ITERATOR} =
           Apache::lonnavmaps::iterator->new ($self->{NAV_MAP}, $firstResource,             Apache::lonnavmaps::DFSiterator->new ($self->{NAV_MAP}, $firstResource, 
                      $finishResource, $self->{FILTER}, $self->{ALREADY_SEEN},                       $finishResource, $self->{FILTER}, $self->{ALREADY_SEEN},
      $self->{CONDITION});                                               $self->{CONDITION}, $self->{DIRECTION});
     }      }
   
     return $self->{HERE};      return $self->{HERE};
 }  }
   
 =pod  # Identical to the full iterator methods of the same name. Hate to copy/paste
   # but I also hate to "inherit" either iterator from the other.
 The other method available on the iterator is B<getStack>, which returns an array populated with the current 'stack' of maps, as references to the resource objects. Example: This is useful when making the navigation map, as we need to check whether we are under a page map to see if we need to link directly to the resource, or to the page. The first elements in the array will correspond to the top of the stack (most inclusive map).  
   
 =cut  
   
 sub getStack {  sub getStack {
     my $self=shift;      my $self=shift;
Line 1920  sub populateStack { Line 2831  sub populateStack {
     my $self=shift;      my $self=shift;
     my $stack = shift;      my $stack = shift;
   
     push @$stack, $self->{HERE};      push @$stack, $self->{HERE} if ($self->{HERE});
   
     if ($self->{RECURSIVE_ITERATOR_FLAG}) {      if ($self->{RECURSIVE_ITERATOR_FLAG}) {
         $self->{RECURSIVE_ITERATOR}->populateStack($stack);          $self->{RECURSIVE_ITERATOR}->populateStack($stack);
Line 1935  use Apache::lonnet; Line 2846  use Apache::lonnet;
   
 =pod  =pod
   
 =head1 Object: resource  =head1 Object: resource 
   
 A resource object encapsulates a resource in a resource map, allowing easy manipulation of the resource, querying the properties of the resource (including user properties), and represents a reference that can be used as the canonical representation of the resource by lonnavmap clients like renderers.  
   
 A resource only makes sense in the context of a navmap, as some of the data is stored in the navmap object.  
   
 You will probably never need to instantiate this object directly. Use Apache::lonnavmap::navmap, and use the "start" method to obtain the starting resource.  
   
 =head2 Public Members  
   
 resource objects have a hash called DATA ($resourceRef->{DATA}) that you can store whatever you want in. This allows you to easily do two-pass algorithms without worrying about managing your own resource->data hash.  X<resource, navmap object>
   A resource object encapsulates a resource in a resource map, allowing
 =head2 Methods  easy manipulation of the resource, querying the properties of the
   resource (including user properties), and represents a reference that
 =over 4  can be used as the canonical representation of the resource by
   lonnavmap clients like renderers.
 =item * B<new>($navmapRef, $idString): The first arg is a reference to the parent navmap object. The second is the idString of the resource itself.   
   A resource only makes sense in the context of a navmap, as some of the
   data is stored in the navmap object.
   
   You will probably never need to instantiate this object directly. Use
   Apache::lonnavmaps::navmap, and use the "start" method to obtain the
   starting resource.
   
   Resource objects respect the parameter_hiddenparts, which suppresses 
   various parts according to the wishes of the map author. As of this
   writing, there is no way to override this parameter, and suppressed
   parts will never be returned, nor will their response types or ids be
   stored.
   
   =head2 Overview
   
   A B<Resource> is the most granular type of object in LON-CAPA that can
   be included in a course. It can either be a particular resource, like
   an HTML page, external resource, problem, etc., or it can be a
   container sequence, such as a "page" or a "map".
   
   To see a sequence from the user's point of view, please see the
   B<Creating a Course: Maps and Sequences> chapter of the Author's
   Manual.
   
   A Resource Object, once obtained from a navmap object via a B<getBy*>
   method of the navmap, or from an iterator, allows you to query
   information about that resource.
   
   Generally, you do not ever want to create a resource object yourself,
   so creation has been left undocumented. Always retrieve resources
   from navmap objects.
   
   =head3 Identifying Resources
   
   X<big hash>Every resource is identified by a Resource ID in the big hash that is
   unique to that resource for a given course. X<resource ID, in big hash>
   The Resource ID has the form #.#, where the first number is the same
   for every resource in a map, and the second is unique. For instance,
   for a course laid out like this:
   
    * Problem 1
    * Map
      * Resource 2
      * Resource 3
   
   C<Problem 1> and C<Map> will share a first number, and C<Resource 2>
   C<Resource 3> will share a first number. The second number may end up
   re-used between the two groups.
   
   The resource ID is only used in the big hash, but can be used in the
   context of a course to identify a resource easily. (For instance, the
   printing system uses it to record which resources from a sequence you 
   wish to print.)
   
   X<symb> X<resource, symb>
   All resources also have B<symb>s, which uniquely identify a resource
   in a course. Many internal LON-CAPA functions expect a symb. A symb
   carries along with it the URL of the resource, and the map it appears
   in. Symbs are much larger then resource IDs.
   
 =cut  =cut
   
Line 1966  sub new { Line 2928  sub new {
   
     # Store this new resource in the parent nav map's cache.      # Store this new resource in the parent nav map's cache.
     $self->{NAV_MAP}->{RESOURCE_CACHE}->{$self->{ID}} = $self;      $self->{NAV_MAP}->{RESOURCE_CACHE}->{$self->{ID}} = $self;
       $self->{RESOURCE_ERROR} = 0;
   
     # A hash that can be used by two-pass algorithms to store data      # A hash that can be used by two-pass algorithms to store data
     # about this resource in. Not used by the resource object      # about this resource in. Not used by the resource object
Line 1977  sub new { Line 2940  sub new {
     return $self;      return $self;
 }  }
   
   # private function: simplify the NAV_HASH lookups we keep doing
   # pass the name, and to automatically append my ID, pass a true val on the
   # second param
   sub navHash {
       my $self = shift;
       my $param = shift;
       my $id = shift;
       return $self->{NAV_MAP}->navhash($param . ($id?$self->{ID}:""));
   }
   
 =pod  =pod
   
 =item * B<is_map>: Returns true if this is a map, false otherwise.  =head2 Methods
   
 =item * B<title>: Returns title.  Once you have a resource object, here's what you can do with it:
   
   =head3 Attribute Retrieval
   
   Every resource has certain attributes that can be retrieved and used:
   
   =over 4
   
 =item * B<type>: Returns the type of the resource, "start", "normal", or "finish".   =item * B<ID>: Every resource has an ID that is unique for that
       resource in the course it is in. The ID is actually in the hash
       representing the resource, so for a resource object $res, obtain
       it via C<$res->{ID}).
   
 =item * B<problem>: Returns true if the resource is a problem type, false otherwise. (Looks at the extension on the src field.)  =item * B<compTitle>:
   
   Returns a "composite title", that is equal to $res->title() if the
   resource has a title, and is otherwise the last part of the URL (e.g.,
   "problem.problem").
   
   =item * B<ext>:
   
   Returns true if the resource is external.
   
   =item * B<kind>:
   
   Returns the kind of the resource from the compiled nav map.
   
   =item * B<randomout>:
   
   Returns true if this resource was chosen to NOT be shown to the user
   by the random map selection feature. In other words, this is usually
   false.
   
   =item * B<randompick>:
   
   Returns true for a map if the randompick feature is being used on the
   map. (?)
   
   =item * B<src>:
   
   Returns the source for the resource.
   
   =item * B<symb>:
   
   Returns the symb for the resource.
   
   =item * B<title>:
   
   Returns the title of the resource.
   
 =back  =back
   
 =cut  =cut
   
 # private function: simplify the NAV_HASH lookups we keep doing  
 # pass the name, and to automatically append my ID, pass a true val on the  
 # second param  
 sub navHash {  
     my $self = shift;  
     my $param = shift;  
     my $id = shift;  
     return $self->{NAV_MAP}->{NAV_HASH}->{$param . ($id?$self->{ID}:"")};  
 }  
   
 # These info functions can be used directly, as they don't return  # These info functions can be used directly, as they don't return
 # resource information.  # resource information.
 sub title { my $self=shift; return $self->navHash("title_", 1); }  sub comesfrom { my $self=shift; return $self->navHash("comesfrom_", 1); }
 sub type { my $self=shift; return $self->navHash("type_", 1); }  sub ext { my $self=shift; return $self->navHash("ext_", 1) eq 'true:'; }
   sub from { my $self=shift; return $self->navHash("from_", 1); }
   # considered private and undocumented
 sub goesto { my $self=shift; return $self->navHash("goesto_", 1); }  sub goesto { my $self=shift; return $self->navHash("goesto_", 1); }
 # "to" can return a comma seperated list for branches  
 sub to { my $self=shift; return $self->navHash("to_", 1); }  
 sub kind { my $self=shift; return $self->navHash("kind_", 1); }  sub kind { my $self=shift; return $self->navHash("kind_", 1); }
   sub randomout { my $self=shift; return $self->navHash("randomout_", 1); }
   sub randompick { 
       my $self = shift;
       return $self->{NAV_MAP}->{PARM_HASH}->{$self->symb .
                                                  '.0.parameter_randompick'};
   }
 sub src {   sub src { 
     my $self=shift;      my $self=shift;
     return $self->navHash("src_", 1);      return $self->navHash("src_", 1);
Line 2021  sub symb { Line 3034  sub symb {
          $self->navHash('map_id_'.$first))            $self->navHash('map_id_'.$first)) 
         . '___' . $second . '___' . $symbSrc;          . '___' . $second . '___' . $symbSrc;
 }  }
 sub is_problem {  sub title { 
     my $self=shift;      my $self=shift; 
     my $src = $self->src();      if ($self->{ID} eq '0.0') {
     return ($src =~ /problem$/);   # If this is the top-level map, return the title of the course
    # since this map can not be titled otherwise.
    return $ENV{'course.'.$ENV{'request.course.id'}.'.description'};
       }
       return $self->navHash("title_", 1); }
   # considered private and undocumented
   sub to { my $self=shift; return $self->navHash("to_", 1); }
   sub compTitle {
       my $self = shift;
       my $title = $self->title();
       $title=~s/\&colon\;/\:/gs;
       if (!$title) {
           $title = $self->src();
           $title = substr($title, rindex($title, '/') + 1);
       }
       return $title;
 }  }
   =pod
   
   B<Predicate Testing the Resource>
   
   These methods are shortcuts to deciding if a given resource has a given property.
   
   =over 4
   
   =item * B<is_map>:
   
   Returns true if the resource is a map type.
   
   =item * B<is_problem>:
   
   Returns true if the resource is a problem type, false
   otherwise. (Looks at the extension on the src field; might need more
   to work correctly.)
   
   =item * B<is_page>:
   
   Returns true if the resource is a page.
   
   =item * B<is_sequence>:
   
   Returns true if the resource is a sequence.
   
   =back
   
   =cut
   
   
 sub is_html {  sub is_html {
     my $self=shift;      my $self=shift;
     my $src = $self->src();      my $src = $self->src();
     return ($src =~ /html$/);      return ($src =~ /html$/);
 }  }
 sub is_sequence {  sub is_map { my $self=shift; return defined($self->navHash("is_map_", 1)); }
   sub is_page {
     my $self=shift;      my $self=shift;
     my $src = $self->src();      my $src = $self->src();
     return ($src =~ /sequence$/);      return $self->navHash("is_map_", 1) && 
    $self->navHash("map_type_" . $self->map_pc()) eq 'page';
 }  }
 sub is_page {  sub is_problem {
     my $self=shift;      my $self=shift;
     my $src = $self->src();      my $src = $self->src();
     return ($src =~ /page$/);      return ($src =~ /problem$/);
   }
   sub is_sequence {
       my $self=shift;
       my $src = $self->src();
       return $self->navHash("is_map_", 1) && 
    $self->navHash("map_type_" . $self->map_pc()) eq 'sequence';
 }  }
   
   # Private method: Shells out to the parmval in the nav map, handler parts.
   
   
 # Move this into POD: In order to use these correctly, courseopt  
 # and useropt need to be generated  
 sub parmval {  sub parmval {
     my $self = shift;      my $self = shift;
     my $what = shift;      my $what = shift;
     my $part = shift || "0";      my $part = shift;
       if (!defined($part)) { 
           $part = '0'; 
       }
     return $self->{NAV_MAP}->parmval($part.'.'.$what, $self->symb());      return $self->{NAV_MAP}->parmval($part.'.'.$what, $self->symb());
 }  }
   
 #####  =pod
 # Map Queries  
 #####  
   
 # These methods relate to whether or not the resource is a map, and the   B<Map Methods>
 # attributes of that map.  
   These methods are useful for getting information about the map
   properties of the resource, if the resource is a map (B<is_map>).
   
   =over 4
   
   =item * B<map_finish>:
   
   Returns a reference to a resource object corresponding to the finish
   resource of the map.
   
   =item * B<map_pc>:
   
   Returns the pc value of the map, which is the first number that
   appears in the resource ID of the resources in the map, and is the
   number that appears around the middle of the symbs of the resources in
   that map.
   
   =item * B<map_start>:
   
   Returns a reference to a resource object corresponding to the start
   resource of the map.
   
   =item * B<map_type>:
   
   Returns a string with the type of the map in it.
   
   =back
   
   =cut
   
 sub is_map { my $self=shift; return defined($self->navHash("is_map_", 1)); }  
 sub map_finish {  sub map_finish {
     my $self = shift;      my $self = shift;
     my $src = $self->src();      my $src = $self->src();
       $src = Apache::lonnet::clutter($src);
     my $res = $self->navHash("map_finish_$src", 0);      my $res = $self->navHash("map_finish_$src", 0);
     $res = $self->{NAV_MAP}->getById($res);      $res = $self->{NAV_MAP}->getById($res);
     return $res;      return $res;
 }  }
   sub map_pc {
       my $self = shift;
       my $src = $self->src();
       return $self->navHash("map_pc_$src", 0);
   }
 sub map_start {  sub map_start {
     my $self = shift;      my $self = shift;
     my $src = $self->src();      my $src = $self->src();
       $src = Apache::lonnet::clutter($src);
     my $res = $self->navHash("map_start_$src", 0);      my $res = $self->navHash("map_start_$src", 0);
     $res = $self->{NAV_MAP}->getById($res);      $res = $self->{NAV_MAP}->getById($res);
     return $res;      return $res;
 }  }
 sub map_pc {  
     my $self = shift;  
     my $src = $self->src();  
     return $self->navHash("map_pc_$src", 0);  
 }  
 sub map_type {  sub map_type {
     my $self = shift;      my $self = shift;
     my $pc = $self->map_pc();      my $pc = $self->map_pc();
     return $self->navHash("map_type_$pc", 0);      return $self->navHash("map_type_$pc", 0);
 }  }
   
   
   
 #####  #####
 # Property queries  # Property queries
 #####  #####
Line 2103  sub map_type { Line 3195  sub map_type {
   
 =head2 Resource Parameters  =head2 Resource Parameters
   
 In order to use the resource parameters correctly, the nav map must have been instantiated with genCourseAndUserOptions set to true, so the courseopt and useropt is read correctly. Then, you can call these functions to get the relevant parameters for the resource. Each function defaults to "part 0", but can be directed to another part by passing the part as the second parameter.  In order to use the resource parameters correctly, the nav map must
   have been instantiated with genCourseAndUserOptions set to true, so
 These methods are responsible for getting the parameter correct, not merely reflecting the contents of the GDBM hashes. As we move towards dates relative to other dates, these methods should be updated to reflect that. (Then, anybody using these methods won't have to update their code.)  the courseopt and useropt is read correctly. Then, you can call these
   functions to get the relevant parameters for the resource. Each
   function defaults to part "0", but can be directed to another part by
   passing the part as the parameter.
   
   These methods are responsible for getting the parameter correct, not
   merely reflecting the contents of the GDBM hashes. As we move towards
   dates relative to other dates, these methods should be updated to
   reflect that. (Then, anybody using these methods will not have to update
   their code.)
   
 =over 4  =over 4
   
 =item * B<acc>: Get the Client IP/Name Access Control information.  =item * B<acc>:
   
   Get the Client IP/Name Access Control information.
   
   =item * B<answerdate>:
   
   Get the answer-reveal date for the problem.
   
   =item * B<awarded>: 
   
   Gets the awarded value for the problem part. Requires genUserData set to
   true when the navmap object was created.
   
   =item * B<duedate>:
   
   Get the due date for the problem.
   
   =item * B<tries>:
   
   Get the number of tries the student has used on the problem.
   
   =item * B<maxtries>:
   
   Get the number of max tries allowed.
   
 =item * B<answerdate>: Get the answer-reveal date for the problem.  =item * B<opendate>:
   
 =item * B<duedate>: Get the due date for the problem.  Get the open date for the problem.
   
 =item * B<tries>: Get the number of tries the student has used on the problem.  =item * B<sig>:
   
 =item * B<maxtries>: Get the number of max tries allowed.  Get the significant figures setting.
   
 =item * B<opendate>: Get the open date for the problem.  =item * B<tol>:
   
 =item * B<sig>: Get the significant figures setting.  Get the tolerance for the problem.
   
 =item * B<tol>: Get the tolerance for the problem.  =item * B<tries>:
   
 =item * B<type>: Get the question type for the problem.  Get the number of tries the user has already used on the problem.
   
 =item * B<weight>: Get the weight for the problem.  =item * B<type>:
   
   Get the question type for the problem.
   
   =item * B<weight>:
   
   Get the weight for the problem.
   
 =back  =back
   
Line 2146  sub answerdate { Line 3276  sub answerdate {
     }      }
     return $self->parmval("answerdate", $part);      return $self->parmval("answerdate", $part);
 }  }
   sub awarded { 
       my $self = shift; my $part = shift;
       $self->{NAV_MAP}->get_user_data();
       if (!defined($part)) { $part = '0'; }
       return $self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$part.'.awarded'};
   }
 sub duedate {  sub duedate {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("duedate", $part);      return $self->parmval("duedate", $part);
Line 2162  sub opendate { Line 3298  sub opendate {
     }      }
     return $self->parmval("opendate");      return $self->parmval("opendate");
 }  }
   sub problemstatus {
       (my $self, my $part) = @_;
       return $self->parmval("problemstatus", $part);
   }
 sub sig {  sub sig {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("sig", $part);      return $self->parmval("sig", $part);
Line 2170  sub tol { Line 3310  sub tol {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("tol", $part);      return $self->parmval("tol", $part);
 }  }
   sub tries { 
       my $self = shift; 
       my $tries = $self->queryRestoreHash('tries', shift);
       if (!defined($tries)) { return '0';}
       return $tries;
   }
 sub type {  sub type {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("type", $part);      return $self->parmval("type", $part);
 }  }
 sub weight {  sub weight { 
     (my $self, my $part) = @_;      my $self = shift; my $part = shift;
     return $self->parmval("weight", $part);      if (!defined($part)) { $part = '0'; }
 }      return &Apache::lonnet::EXT('resource.'.$part.'.weight',
 sub tries {   $self->symb(), $ENV{'user.domain'},
     my $self = shift;   $ENV{'user.name'}, 
     my $part = shift;   $ENV{'request.course.sec'});
     $part = '0' if (!defined($part));  
   
     # Make sure return hash is loaded, should error check  
     $self->getReturnHash();  
       
     my $tries = $self->{RETURN_HASH}->{'resource.'.$part.'.tries'};  
     if (!defined($tries)) {return '0';}  
     return $tries;  
 }  }
   
 # Multiple things need this  # Multiple things need this
Line 2196  sub getReturnHash { Line 3335  sub getReturnHash {
     my $self = shift;      my $self = shift;
           
     if (!defined($self->{RETURN_HASH})) {      if (!defined($self->{RETURN_HASH})) {
         my %tmpHash = &Apache::lonnet::restore($self->symb());          my %tmpHash  = &Apache::lonnet::restore($self->symb());
         $self->{RETURN_HASH} = \%tmpHash;          $self->{RETURN_HASH} = \%tmpHash;
     }      }
 }         }       
Line 2223  Misc. functions for the resource. Line 3362  Misc. functions for the resource.
   
 =over 4  =over 4
   
 =item * B<hasDiscussion>: Returns a false value if there has been discussion since the user last logged in, true if there has. Always returns false if the discussion data was not extracted when the nav map was constructed.  =item * B<hasDiscussion>:
   
 =item * B<getFeedback>: Gets the feedback for the resource and returns the raw feedback string for the resource, or the null string if there is no feedback or the email data was not extracted when the nav map was constructed. Usually used like this:  Returns a false value if there has been discussion since the user last
   logged in, true if there has. Always returns false if the discussion
   data was not extracted when the nav map was constructed.
   
   =item * B<getFeedback>:
   
   Gets the feedback for the resource and returns the raw feedback string
   for the resource, or the null string if there is no feedback or the
   email data was not extracted when the nav map was constructed. Usually
   used like this:
   
  for (split(/\,/, $res->getFeedback())) {   for (split(/\,/, $res->getFeedback())) {
     my $link = &Apache::lonnet::escape($_);      my $link = &Apache::lonnet::escape($_);
Line 2242  sub hasDiscussion { Line 3390  sub hasDiscussion {
   
 sub getFeedback {  sub getFeedback {
     my $self = shift;      my $self = shift;
     return $self->{NAV_MAP}->getFeedback($self->symb());      my $source = $self->src();
       if ($source =~ /^\/res\//) { $source = substr $source, 5; }
       return $self->{NAV_MAP}->getFeedback($source);
   }
   
   sub getErrors {
       my $self = shift;
       my $source = $self->src();
       if ($source =~ /^\/res\//) { $source = substr $source, 5; }
       return $self->{NAV_MAP}->getErrors($source);
 }  }
   
 =pod  =pod
   
 =item * B<parts>(): Returns a list reference containing sorted strings corresponding to each part of the problem. To count the number of parts, use the list in a scalar context, and subtract one if greater then two. (One part problems have a part 0. Multi-parts have a part 0, plus a part for each part. You may or may not wish to filter out part 0.)  =item * B<parts>():
   
   Returns a list reference containing sorted strings corresponding to
   each part of the problem. Single part problems have only a part '0'.
   Multipart problems do not return their part '0', since they typically
   do not really matter. 
   
 =item * B<countParts>(): Returns the number of parts of the problem a student can answer. Thus, for single part problems, returns 1. For multipart, it returns the number of parts in the problem, not including psuedo-part 0.  =item * B<countParts>():
   
   Returns the number of parts of the problem a student can answer. Thus,
   for single part problems, returns 1. For multipart, it returns the
   number of parts in the problem, not including psuedo-part 0. 
   
   =item * B<multipart>():
   
   Returns true if the problem is multipart, false otherwise. Use this instead
   of countParts if all you want is multipart/not multipart.
   
   =item * B<responseType>($part):
   
   Returns the response type of the part, without the word "response" on the
   end. Example return values: 'string', 'essay', 'numeric', etc.
   
   =item * B<responseIds>($part):
   
   Retreives the response IDs for the given part as an array reference containing
   strings naming the response IDs. This may be empty.
   
 =back  =back
   
Line 2258  sub getFeedback { Line 3439  sub getFeedback {
 sub parts {  sub parts {
     my $self = shift;      my $self = shift;
   
       if ($self->ext) { return []; }
   
     $self->extractParts();      $self->extractParts();
     return $self->{PARTS};      return $self->{PARTS};
 }  }
Line 2266  sub countParts { Line 3449  sub countParts {
     my $self = shift;      my $self = shift;
           
     my $parts = $self->parts();      my $parts = $self->parts();
       
     if (scalar(@{$parts}) == 1) { return 1;}  
   
     return scalar(@{$parts}) - 1;      # If I left this here, then it's not necessary.
       #my $delta = 0;
       #for my $part (@$parts) {
       #    if ($part eq '0') { $delta--; }
       #}
   
       if ($self->{RESOURCE_ERROR}) {
           return 0;
       }
   
       return scalar(@{$parts}); # + $delta;
 }  }
   
 # Private function: Extracts the parts information and saves it  sub multipart {
       my $self = shift;
       return $self->countParts() > 1;
   }
   
   sub responseType {
       my $self = shift;
       my $part = shift;
   
       $self->extractParts();
       return $self->{RESPONSE_TYPES}->{$part};
   }
   
   sub responseIds {
       my $self = shift;
       my $part = shift;
   
       $self->extractParts();
       return $self->{RESPONSE_IDS}->{$part};
   }
   
   # Private function: Extracts the parts information, both part names and
   # part types, and saves it. 
 sub extractParts {   sub extractParts { 
     my $self = shift;      my $self = shift;
           
     return if ($self->{PARTS});      return if (defined($self->{PARTS}));
       return if ($self->ext);
   
     $self->{PARTS} = [];      $self->{PARTS} = [];
   
     # Retrieve part count      my %parts;
     foreach (split(/\,/,&Apache::lonnet::metadata($self->src(),   
                                                   'allpossiblekeys'))) {      # Retrieve part count, if this is a problem
         if ($_ =~ /^parameter\_(.*)\_opendate$/) {      if ($self->is_problem()) {
             push @{$self->{PARTS}}, $1;          my $metadata = &Apache::lonnet::metadata($self->src(), 'packages');
           if (!$metadata) {
               $self->{RESOURCE_ERROR} = 1;
               $self->{PARTS} = [];
               $self->{PART_TYPE} = {};
               return;
         }          }
           foreach (split(/\,/,$metadata)) {
               if ($_ =~ /^part_(.*)$/) {
                   my $part = $1;
                   # This floods the logs if it blows up
                   if (defined($parts{$part})) {
                       Apache::lonnet::logthis("$part multiply defined in metadata for " . $self->symb());
                     }
   
                   # check to see if part is turned off.
   
                   if (!Apache::loncommon::check_if_partid_hidden($part, $self->symb())) {
                       $parts{$part} = 1;
                   }
               }
           }
           
           
           my @sortedParts = sort keys %parts;
           $self->{PARTS} = \@sortedParts;
   
           my %responseIdHash;
           my %responseTypeHash;
   
   
           # Init the responseIdHash
           foreach (@{$self->{PARTS}}) {
               $responseIdHash{$_} = [];
           }
   
           # Now, the unfortunate thing about this is that parts, part name, and
           # response if are delimited by underscores, but both the part
           # name and response id can themselves have underscores in them.
           # So we have to use our knowlege of part names to figure out 
           # where the part names begin and end, and even then, it is possible
           # to construct ambiguous situations.
           foreach (split /,/, $metadata) {
               if ($_ =~ /^([a-zA-Z]+)response_(.*)/) {
                   my $responseType = $1;
                   my $partStuff = $2;
                   my $partIdSoFar = '';
                   my @partChunks = split /_/, $partStuff;
                   my $i = 0;
   
                   for ($i = 0; $i < scalar(@partChunks); $i++) {
                       if ($partIdSoFar) { $partIdSoFar .= '_'; }
                       $partIdSoFar .= $partChunks[$i];
                       if ($parts{$partIdSoFar}) {
                           my @otherChunks = @partChunks[$i+1..$#partChunks];
                           my $responseId = join('_', @otherChunks);
                           push @{$responseIdHash{$partIdSoFar}}, $responseId;
                           $responseTypeHash{$partIdSoFar} = $responseType;
                           last;
                       }
                   }
               }
           }
   
           $self->{RESPONSE_IDS} = \%responseIdHash;
           $self->{RESPONSE_TYPES} = \%responseTypeHash;
     }      }
       
     # Is this possible to do in one line? - Jeremy  
     my @sortedParts = sort @{$self->{PARTS}};  
     $self->{PARTS} = \@sortedParts;  
   
     return;      return;
 }  }
Line 2299  sub extractParts { Line 3573  sub extractParts {
   
 =head2 Resource Status  =head2 Resource Status
   
 Problem resources have status information, reflecting their various dates and completion statuses. You can obtain this information and import symbolic constants to represent the status.  Problem resources have status information, reflecting their various
   dates and completion statuses.
   
 There are two aspects to the status: the date-related information and the completion information.  There are two aspects to the status: the date-related information and
   the completion information.
   
 Idiomatic usage of these two methods would probably look something like  Idiomatic usage of these two methods would probably look something
   like
   
  foreach ($resource->parts()) {   foreach ($resource->parts()) {
     my $dateStatus = $resource->getDateStatus($_);      my $dateStatus = $resource->getDateStatus($_);
     my $completionStatus = $resource->getCompletionStatus($_);      my $completionStatus = $resource->getCompletionStatus($_);
   
       or
   
       my $status = $resource->status($_);
   
     ... use it here ...      ... use it here ...
  }   }
   
   Which you use depends on exactly what you are looking for. The
   status() function has been optimized for the nav maps display and may
   not precisely match what you need elsewhere.
   
   The symbolic constants shown below can be accessed through the
   resource object: C<$res->OPEN>.
   
 =over 4  =over 4
   
 =item * B<getDateStatus>($part): ($part defaults to 0). A convenience function that returns a symbolic constant telling you about the date status of the part. You should still check to see if there is a due date at all, if you care about that. The possible return values are:  =item * B<getDateStatus>($part):
   
   ($part defaults to 0). A convenience function that returns a symbolic
   constant telling you about the date status of the part. The possible
   return values are:
   
 =back  =back
   
Line 2322  B<Date Codes> Line 3614  B<Date Codes>
   
 =over 4  =over 4
   
 =item * B<OPEN_LATER>: The problem will be opened later.  =item * B<OPEN_LATER>:
   
   The problem will be opened later.
   
   =item * B<OPEN>:
   
   Open and not yet due.
   
   
   =item * B<PAST_DUE_ANSWER_LATER>:
   
 =item * B<OPEN>: Open and not yet due.  The due date has passed, but the answer date has not yet arrived.
   
   =item * B<PAST_DUE_NO_ANSWER>:
   
 =item * B<PAST_DUE_ANSWER_LATER>: The due date has passed, but the answer date has not yet arrived.  The due date has passed and there is no answer opening date set.
   
 =item * B<PAST_DUE_NO_ANSWER>: The due date has passed and there is no answer opening date set.  =item * B<ANSWER_OPEN>:
   
 =item * B<ANSWER_OPEN>: The answer date is here.  The answer date is here.
   
 =item * B<NETWORK_FAILURE>: The information is unknown due to network failure.  =item * B<NETWORK_FAILURE>:
   
   The information is unknown due to network failure.
   
 =back  =back
   
Line 2387  B<> Line 3691  B<>
   
 =over 4  =over 4
   
 =item * B<getCompletionStatus>($part): ($part defaults to 0.) A convenience function that returns a symbolic constant telling you about the completion status of the part, with the following possible results:  =item * B<getCompletionStatus>($part):
   
   ($part defaults to 0.) A convenience function that returns a symbolic
   constant telling you about the completion status of the part, with the
   following possible results:
   
 =back   =back
   
 B<Completion Codes>  B<Completion Codes>
   
 =over 4  =over 4
   
 =item * B<NOT_ATTEMPTED>: Has not been attempted at all.  =item * B<NOT_ATTEMPTED>:
   
   Has not been attempted at all.
   
   =item * B<INCORRECT>:
   
   Attempted, but wrong by student.
   
   =item * B<INCORRECT_BY_OVERRIDE>:
   
   Attempted, but wrong by instructor override.
   
   =item * B<CORRECT>:
   
   Correct or correct by instructor.
   
 =item * B<INCORRECT>: Attempted, but wrong by student.  =item * B<CORRECT_BY_OVERRIDE>:
   
 =item * B<INCORRECT_BY_OVERRIDE>: Attempted, but wrong by instructor override.  Correct by instructor override.
   
 =item * B<CORRECT>: Correct or correct by instructor.  =item * B<EXCUSED>:
   
 =item * B<CORRECT_BY_OVERRIDE>: Correct by instructor override.  Excused. Not yet implemented.
   
 =item * B<EXCUSED>: Excused. Not yet implemented.  =item * B<NETWORK_FAILURE>:
   
 =item * B<NETWORK_FAILURE>: Information not available due to network failure.  Information not available due to network failure.
   
   =item * B<ATTEMPTED>:
   
   Attempted, and not yet graded.
   
 =back  =back
   
Line 2419  sub INCORRECT_BY_OVERRIDE { return 12; } Line 3745  sub INCORRECT_BY_OVERRIDE { return 12; }
 sub CORRECT               { return 13; }  sub CORRECT               { return 13; }
 sub CORRECT_BY_OVERRIDE   { return 14; }  sub CORRECT_BY_OVERRIDE   { return 14; }
 sub EXCUSED               { return 15; }  sub EXCUSED               { return 15; }
   sub ATTEMPTED             { return 16; }
   
 sub getCompletionStatus {  sub getCompletionStatus {
     my $self = shift;      my $self = shift;
     my $part = shift;  
     $part = "0" if (!defined($part));  
     return $self->NETWORK_FAILURE if ($self->{NAV_MAP}->{NETWORK_FAILURE});      return $self->NETWORK_FAILURE if ($self->{NAV_MAP}->{NETWORK_FAILURE});
   
     # Make sure return hash exists      my $status = $self->queryRestoreHash('solved', shift);
     $self->getReturnHash();  
       
     my $status = $self->{RETURN_HASH}->{'resource.'.$part.'.solved'};  
   
     # Left as seperate if statements in case we ever do more with this      # Left as seperate if statements in case we ever do more with this
     if ($status eq 'correct_by_student') {return $self->CORRECT;}      if ($status eq 'correct_by_student') {return $self->CORRECT;}
Line 2437  sub getCompletionStatus { Line 3759  sub getCompletionStatus {
     if ($status eq 'incorrect_attempted') {return $self->INCORRECT; }      if ($status eq 'incorrect_attempted') {return $self->INCORRECT; }
     if ($status eq 'incorrect_by_override') {return $self->INCORRECT_BY_OVERRIDE; }      if ($status eq 'incorrect_by_override') {return $self->INCORRECT_BY_OVERRIDE; }
     if ($status eq 'excused') {return $self->EXCUSED; }      if ($status eq 'excused') {return $self->EXCUSED; }
       if ($status eq 'ungraded_attempted') {return $self->ATTEMPTED; }
     return $self->NOT_ATTEMPTED;      return $self->NOT_ATTEMPTED;
 }  }
   
   sub queryRestoreHash {
       my $self = shift;
       my $hashentry = shift;
       my $part = shift;
       $part = "0" if (!defined($part) || $part eq '');
       return $self->NETWORK_FAILURE if ($self->{NAV_MAP}->{NETWORK_FAILURE});
   
       $self->getReturnHash();
   
       return $self->{RETURN_HASH}->{'resource.'.$part.'.'.$hashentry};
   }
   
 =pod  =pod
   
 B<Composite Status>  B<Composite Status>
   
 Along with directly returning the date or completion status, the resource object includes a convenience function B<status>() that will combine the two status tidbits into one composite status that can represent the status of the resource as a whole. The precise logic is documented in the comments of the status method. The following results may be returned, all available as methods on the resource object ($res->NETWORK_FAILURE()):  Along with directly returning the date or completion status, the
   resource object includes a convenience function B<status>() that will
   combine the two status tidbits into one composite status that can
   represent the status of the resource as a whole. This method represents
   the concept of the thing we want to display to the user on the nav maps
   screen, which is a combination of completion and open status. The precise logic is
   documented in the comments of the status method. The following results
   may be returned, all available as methods on the resource object
   ($res->NETWORK_FAILURE): In addition to the return values that match
   the date or completion status, this function can return "ANSWER_SUBMITTED"
   if that problemstatus parameter value is set to No, suppressing the
   incorrect/correct feedback.
   
 =over 4  =over 4
   
 =item * NETWORK_FAILURE: The network has failed and the information is not available.  =item * B<NETWORK_FAILURE>:
   
   The network has failed and the information is not available.
   
   =item * B<NOTHING_SET>:
   
   No dates have been set for this problem (part) at all. (Because only
   certain parts of a multi-part problem may be assigned, this can not be
   collapsed into "open later", as we do not know a given part will EVER
   be opened. For single part, this is the same as "OPEN_LATER".)
   
   =item * B<CORRECT>:
   
   For any reason at all, the part is considered correct.
   
   =item * B<EXCUSED>:
   
   For any reason at all, the problem is excused.
   
   =item * B<PAST_DUE_NO_ANSWER>:
   
   The problem is past due, not considered correct, and no answer date is
   set.
   
   =item * B<PAST_DUE_ANSWER_LATER>:
   
   The problem is past due, not considered correct, and an answer date in
   the future is set.
   
   =item * B<ANSWER_OPEN>:
   
   The problem is past due, not correct, and the answer is now available.
   
 =item * NOTHING_SET: No dates have been set for this problem (part) at all. (Because only certain parts of a multi-part problem may be assigned, this can not be collapsed into "open later", as we don't know a given part will EVER be opened. For single part, this is the same as "OPEN_LATER".)  =item * B<OPEN_LATER>:
   
 =item * CORRECT: For any reason at all, the part is considered correct.  The problem is not yet open.
   
 =item * EXCUSED: For any reason at all, the problem is excused.  =item * B<TRIES_LEFT>:
   
 =item * PAST_DUE_NO_ANSWER: The problem is past due, not considered correct, and no answer date is set.  The problem is open, has been tried, is not correct, but there are
   tries left.
   
 =item * PAST_DUE_ANSWER_LATER: The problem is past due, not considered correct, and an answer date in the future is set.  =item * B<INCORRECT>:
   
 =item * ANSWER_OPEN: The problem is past due, not correct, and the answer is now available.  The problem is open, and all tries have been used without getting the
   correct answer.
   
 =item * OPEN_LATER: The problem is not yet open.  =item * B<OPEN>:
   
 =item * TRIES_LEFT: The problem is open, has been tried, is not correct, but there are tries left.  The item is open and not yet tried.
   
 =item * INCORRECT: The problem is open, and all tries have been used without getting the correct answer.  =item * B<ATTEMPTED>:
   
 =item * OPEN: The item is open and not yet tried.  The problem has been attempted.
   
   =item * B<ANSWER_SUBMITTED>:
   
   An answer has been submitted, but the student should not see it.
   
 =back  =back
   
 =cut  =cut
   
 sub TRIES_LEFT { return 10; }  sub TRIES_LEFT       { return 20; }
   sub ANSWER_SUBMITTED { return 21; }
   
 sub status {  sub status {
     my $self = shift;      my $self = shift;
Line 2487  sub status { Line 3871  sub status {
     # dimension and 5 entries on the other, which we want to colorize,      # dimension and 5 entries on the other, which we want to colorize,
     # plus network failure and "no date data at all".      # plus network failure and "no date data at all".
   
       #if ($self->{RESOURCE_ERROR}) { return NETWORK_FAILURE; }
     if ($completionStatus == NETWORK_FAILURE) { return NETWORK_FAILURE; }      if ($completionStatus == NETWORK_FAILURE) { return NETWORK_FAILURE; }
   
       my $suppressFeedback = lc($self->parmval("problemstatus", $part)) eq 'no';
   
     # There are a few whole rows we can dispose of:      # There are a few whole rows we can dispose of:
     if ($completionStatus == CORRECT ||      if ($completionStatus == CORRECT ||
         $completionStatus == CORRECT_BY_OVERRIDE ) {          $completionStatus == CORRECT_BY_OVERRIDE ) {
         return CORRECT();           return $suppressFeedback? ANSWER_SUBMITTED : CORRECT; 
       }
   
       if ($completionStatus == ATTEMPTED) {
           return ATTEMPTED;
     }      }
   
     # If it's EXCUSED, then return that no matter what      # If it's EXCUSED, then return that no matter what
Line 2504  sub status { Line 3895  sub status {
         return NOTHING_SET;          return NOTHING_SET;
     }      }
   
     # Now we're down to a 3 (incorrect, incorrect_override, not_attempted)      # Now we're down to a 4 (incorrect, incorrect_override, not_attempted)
     # by 4 matrix (date status).      # by 4 matrix (date statuses).
   
     if ($dateStatus == PAST_DUE_ANSWER_LATER ||      if ($dateStatus == PAST_DUE_ANSWER_LATER ||
         $dateStatus == PAST_DUE_NO_ANSWER ) {          $dateStatus == PAST_DUE_NO_ANSWER ) {
Line 2526  sub status { Line 3917  sub status {
     # If it's WRONG...      # If it's WRONG...
     if ($completionStatus == INCORRECT || $completionStatus == INCORRECT_BY_OVERRIDE) {      if ($completionStatus == INCORRECT || $completionStatus == INCORRECT_BY_OVERRIDE) {
         # and there are TRIES LEFT:          # and there are TRIES LEFT:
         if ($self->tries() < $self->maxtries()) {          if ($self->tries($part) < $self->maxtries($part) || !$self->maxtries($part)) {
             return TRIES_LEFT;              return $suppressFeedback ? ANSWER_SUBMITTED : TRIES_LEFT;
         }          }
         return INCORRECT; # otherwise, return orange; student can't fix this          return $suppressFeedback ? ANSWER_SUBMITTED : INCORRECT; # otherwise, return orange; student can't fix this
     }      }
   
     # Otherwise, it's untried and open      # Otherwise, it's untried and open
Line 2538  sub status { Line 3929  sub status {
   
 =pod  =pod
   
   B<Completable>
   
   The completable method represents the concept of I<whether the student can
   currently do the problem>. If the student can do the problem, which means
   that it is open, there are tries left, and if the problem is manually graded
   or the grade is suppressed via problemstatus, the student has not tried it
   yet, then the method returns 1. Otherwise, it returns 0, to indicate that 
   either the student has tried it and there is no feedback, or that for
   some reason it is no longer completable (not open yet, successfully completed,
   out of tries, etc.). As an example, this is used as the filter for the
   "Uncompleted Homework" option for the nav maps.
   
   If this does not quite meet your needs, do not fiddle with it (unless you are
   fixing it to better match the student's conception of "completable" because
   it's broken somehow)... make a new method.
   
   =cut
   
   sub completable {
       my $self = shift;
       if (!$self->is_problem()) { return 0; }
       my $partCount = $self->countParts();
   
       foreach my $part (@{$self->parts()}) {
           if ($part eq '0' && $partCount != 1) { next; }
           my $status = $self->status($part);
           # "If any of the parts are open, or have tries left (implies open),
           # and it is not "attempted" (manually graded problem), it is
           # not "complete"
    if ($self->getCompletionStatus($part) == ATTEMPTED() ||
       $status == ANSWER_SUBMITTED() ) {
       # did this part already, as well as we can
       next;
    }
    if ($status == OPEN() || $status == TRIES_LEFT()) {
       return 1;
    }
       }
           
       # If all the parts were complete, so was this problem.
       return 0;
   }
   
   =pod
   
 =head2 Resource/Nav Map Navigation  =head2 Resource/Nav Map Navigation
   
 =over 4  =over 4
   
 =item * B<getNext>(): Gets the next resource in the navmap after this one.  =item * B<getNext>():
   
 =cut  Retreive an array of the possible next resources after this
   one. Always returns an array, even in the one- or zero-element case.
   
   =item * B<getPrevious>():
   
 # For the simple single-link case, to get from a resource to the next  Retreive an array of the possible previous resources from this
 # resource, you need to look up the "to_" link in the nav hash, then  one. Always returns an array, even in the one- or zero-element case.
 # follow that with the "goesto_" link.  
   =cut
   
 sub getNext {  sub getNext {
     my $self = shift;      my $self = shift;
     my $alreadySeenHash = shift;  
     my @branches;      my @branches;
     my $to = $self->to();      my $to = $self->to();
     foreach my $branch ( split(/\,/, $to) ) {      foreach my $branch ( split(/,/, $to) ) {
         my $choice = $self->{NAV_MAP}->getById($branch);          my $choice = $self->{NAV_MAP}->getById($branch);
         my $next = $choice->goesto();          my $next = $choice->goesto();
         $next = $self->{NAV_MAP}->getById($next);          $next = $self->{NAV_MAP}->getById($next);
   
         # Don't remember it if we've already seen it or if          push @branches, $next;
  # the student doesn't have browse priviledges      }
  my $browsePriv = &Apache::lonnet::allowed('bre', $self->src);      return \@branches;
         if (!defined($alreadySeenHash) ||  }
             !defined($alreadySeenHash->{$next->{ID}}) ||  
     ($browsePriv ne '2' && $browsePriv ne 'F')) {  sub getPrevious {
                 push @branches, $next;      my $self = shift;
             }      my @branches;
       my $from = $self->from();
       foreach my $branch ( split /,/, $from) {
           my $choice = $self->{NAV_MAP}->getById($branch);
           my $prev = $choice->comesfrom();
           $prev = $self->{NAV_MAP}->getById($prev);
   
           push @branches, $prev;
     }      }
     return \@branches;      return \@branches;
 }  }
   
   sub browsePriv {
       my $self = shift;
       if (defined($self->{BROWSE_PRIV})) {
           return $self->{BROWSE_PRIV};
       }
   
       $self->{BROWSE_PRIV} = &Apache::lonnet::allowed('bre', $self->src());
   }
   
 =pod  =pod
   
 =back  =back

Removed from v.1.64  
changed lines
  Added in v.1.222


FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>