Diff for /loncom/interface/lonnavmaps.pm between versions 1.101 and 1.415.4.1

version 1.101, 2002/11/08 20:58:13 version 1.415.4.1, 2009/09/15 00:52:39
Line 1 Line 1
   
 # The LearningOnline Network with CAPA  # The LearningOnline Network with CAPA
 # Navigate Maps Handler  # Navigate Maps Handler
 #  #
Line 26 Line 25
 #  #
 # http://www.lon-capa.org/  # http://www.lon-capa.org/
 #  #
 # (Page Handler  ###
 #  
 # (TeX Content Handler  
 #  
 # 05/29/00,05/30 Gerd Kortemeyer)  
 # 08/30,08/31,09/06,09/14,09/15,09/16,09/19,09/20,09/21,09/23,  
 # 10/02,10/10,10/14,10/16,10/18,10/19,10/31,11/6,11/14,11/16 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  
 # 1/1 Gerd Kortemeyer  
 #  
   
 package Apache::lonnavmaps;  package Apache::lonnavmaps;
   
 use strict;  use strict;
 use Apache::Constants qw(:common :http);  
 use Apache::lonnet();  
 use Apache::loncommon();  
 use GDBM_File;  use GDBM_File;
   use Apache::loncommon();
   use Apache::lonenc();
   use Apache::lonlocal;
   use Apache::lonnet;
 use POSIX qw (floor strftime);  use POSIX qw (floor strftime);
   use Time::HiRes qw( gettimeofday tv_interval );
 sub handler {  use LONCAPA;
     my $r = shift;  use DateTime();
   
     &Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING});  # symbolic constants
   sub SYMB { return 1; }
     # Handle header-only request  sub URL { return 2; }
     if ($r->header_only) {  sub NOTHING { return 3; }
         if ($ENV{'browser.mathml'}) {  
             $r->content_type('text/xml');  # Some data
         } else {  
             $r->content_type('text/html');  my $resObj = "Apache::lonnavmaps::resource";
         }  
         $r->send_http_header;  # Keep these mappings in sync with lonquickgrades, which uses the colors
         return OK;  # instead of the icons.
     }  my %statusIconMap = 
       (
     # Send header, don't cache this page       $resObj->CLOSED       => '',
     if ($ENV{'browser.mathml'}) {       $resObj->OPEN         => 'navmap.open.gif',
         $r->content_type('text/xml');       $resObj->CORRECT      => 'navmap.correct.gif',
     } else {       $resObj->PARTIALLY_CORRECT      => 'navmap.partial.gif',
         $r->content_type('text/html');       $resObj->INCORRECT    => 'navmap.wrong.gif',
     }       $resObj->ATTEMPTED    => 'navmap.ellipsis.gif',
     &Apache::loncommon::no_cache($r);       $resObj->ERROR        => ''
     $r->send_http_header;       );
   
     # Create the nav map the nav map  my %iconAltTags = 
     my $navmap = Apache::lonnavmaps::navmap->new(      ( 'navmap.correct.gif' => 'Correct',
                         $ENV{"request.course.fn"}.".db",        'navmap.wrong.gif'   => 'Incorrect',
                         $ENV{"request.course.fn"}."_parms.db", 1, 1);        'navmap.open.gif'    => 'Open' );
   
   # Defines a status->color mapping, null string means don't color
     if (!defined($navmap)) {  my %colormap = 
         my $requrl = $r->uri;      ( $resObj->NETWORK_FAILURE        => '',
         $ENV{'user.error.msg'} = "$requrl:bre:0:0:Course not initialized";        $resObj->CORRECT                => '',
         return HTTP_NOT_ACCEPTABLE;        $resObj->EXCUSED                => '#3333FF',
     }        $resObj->PAST_DUE_ANSWER_LATER  => '',
         $resObj->PAST_DUE_NO_ANSWER     => '',
     # Header        $resObj->ANSWER_OPEN            => '#006600',
     $r->print(&Apache::loncommon::bodytag('Navigate Course Map','',        $resObj->OPEN_LATER             => '',
                                           ''));        $resObj->TRIES_LEFT             => '',
     $r->print('<script>window.focus();</script>');        $resObj->INCORRECT              => '',
         $resObj->OPEN                   => '',
     $r->print('<table border="0" cellpadding="2" cellspacing="0">');        $resObj->NOTHING_SET            => '',
     my $date=localtime;        $resObj->ATTEMPTED              => '',
     $r->print('<tr><td align="right" valign="bottom">Key:&nbsp;&nbsp;</td>');        $resObj->ANSWER_SUBMITTED       => '',
         $resObj->PARTIALLY_CORRECT      => '#006600'
     # Print discussions and feedback header        );
     if ($navmap->{LAST_CHECK}) {  # And a special case in the nav map; what to do when the assignment
         $r->print('<td align="center" valign="bottom">&nbsp;&nbsp;'.  # is not yet done and due in less than 24 hours
                   '<img src="/adm/lonMisc/chat.gif"> New discussion since '.  my $hurryUpColor = "#FF0000";
                   strftime("%A, %b %e at %I:%M %P", localtime($navmap->{LAST_CHECK})).  
                   '</td><td align="center" valign="bottom">&nbsp;&nbsp;'.  sub close {
                   '<img src="/adm/lonMisc/feedback.gif"> New message (click to open)<p>'.      if ($env{'environment.remotenavmap'} ne 'on') { return ''; }
                   '</td>');       return(<<ENDCLOSE);
     } else {  <script type="text/javascript">
         $r->print('<td align="center" valign="bottom">&nbsp;&nbsp;'.  window.status='Accessing Nav Control';
                   '<img src="/adm/lonMisc/chat.gif"> Discussions</td><td align="center" valign="bottom">'.  menu=window.open("/adm/rat/empty.html","loncapanav",
                   '&nbsp;&nbsp;<img src="/adm/lonMisc/feedback.gif"> New message (click to open)'.                   "height=600,width=400,scrollbars=1");
                   '</td>');   window.status='Closing Nav Control';
     }  menu.close();
     $r->print('</tr></table>');  window.status='Done.';
   </script>
     my $condition = 0;  ENDCLOSE
     if ($ENV{'form.condition'}) {  }
         $condition = 1;  
     }  sub update {
       if ($env{'environment.remotenavmap'} ne 'on') { return ''; }
     if ($condition) {      if (!$env{'request.course.id'}) { return ''; }
         $r->print('<a href="navmaps?condition=0&filter=">Close All Folders</a>');      if ($ENV{'REQUEST_URI'}=~m|^/adm/navmaps|) { return ''; }
     } else {      return(<<ENDUPDATE);
         $r->print('<a href="navmaps?condition=1&filter=">Open All Folders</a>');  <form name="navform"></form>
     }  <script type="text/javascript">
   this.document.navform.action='/adm/navmaps#curloc';
     $r->print('<br>&nbsp;');  this.document.navform.target='loncapanav';
     $r->rflush();  this.document.navform.submit();
   </script>
     # Now that we've displayed some stuff to the user, init the navmap  ENDUPDATE
     $navmap->init();  
   
     # Check that it's defined  
     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  
     # is technically not proper, but should be harmless  
     my $res = $navmap->firstResource();  
   
     # These are some data tables, which make it easy to change some of  
     # of the specific visualization parameters if desired.  
   
     # 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 = "#FF0000";  
   
     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',  
           $res->ATTEMPTED          => 'navmap.open.gif' );  
   
     my %iconAltTags =   
         ( 'navmap.correct.gif' => 'Correct',  
           'navmap.wrong.gif'   => 'Incorrect',  
           'navmap.open.gif'    => 'Open' );  
   
     my %condenseStatuses =  
         ( $res->NETWORK_FAILURE    => 1,  
           $res->NOTHING_SET        => 1,  
           $res->CORRECT            => 1 );  
   
     my %filterHash;  
     # Figure out what we're not displaying  
     foreach (split(/\,/, $ENV{"form.filter"})) {  
         if ($_) {  
             $filterHash{$_} = "1";  
         }  
     }  
   
     # Is this a new-style course? If so, we want to suppress showing the top-level  
     # maps in their own folders, in favor of "inlining" them.  
     my $topResource = $navmap->getById("0.0");  
     my $inlineTopLevelMaps = $topResource->src() =~ m|^/uploaded/.*default\.sequence$|;  
   
     my $currenturl = $ENV{'form.postdata'};  
     $currenturl=~s/^http\:\/\///;  
     $currenturl=~s/^[^\/]+//;  
   
     # alreadyHere allows us to only open the maps necessary to view  
     # the current location once, while at the same time remembering  
     # the current location. Without that check, the user would never  
     # be able to close those maps; the user would close it, and the  
     # currenturl scan would re-open it.  
     my $queryAdd = "postdata=" . &Apache::lonnet::escape($currenturl) .  
         "&alreadyHere=1";  
   
     # Begin the HTML table  
     # four cols: resource + indent, chat+feedback, icon, text string  
     $r->print('<table cellspacing="0" cellpadding="3" border="0" bgcolor="#FFFFFF">' ."\n");  
   
     # This needs to be updated to use symbs from the remote,   
     # instead of uris. The changes to this and the main rendering  
     # loop should be obvious.  
     # Here's a simple example of the iterator.  
     # Preprocess the map: Look for current URL, force inlined maps to display  
   
     my $mapIterator = $navmap->getIterator(undef, undef, \%filterHash, 1);  
     my $found = 0;  
     my $depth = 1;  
     my $currentUrlIndex = 0; # 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 $currentUrlDelta = 5; # change this to change how many resources are displayed  
                              # before the current resource when using #current  
     $mapIterator->next(); # discard the first BEGIN_MAP  
     my $curRes = $mapIterator->next();  
     my $counter = 0;  
       
     while ($depth > 0) {  
         if ($curRes == $mapIterator->BEGIN_MAP()) { $depth++; }  
         if ($curRes == $mapIterator->END_MAP()) { $depth--; }  
   
         if (ref($curRes)) { $counter++; }  
   
         my $mapStack = $mapIterator->getStack();  
         if ($currenturl && !$ENV{'form.alreadyHere'} && ref($curRes) &&   
             $curRes->src() eq $currenturl) {  
             # If this is the correct resource, be sure to   
             # show it by making sure the containing maps  
             # are open.  
   
             # 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.  
             $currentUrlIndex = $counter;  
               
             # Ensure the parent maps are open  
             for my $map (@{$mapStack}) {  
                 if ($condition) {  
                     undef $filterHash{$map->map_pc()};  
                 } else {  
                     $filterHash{$map->map_pc()} = 1;  
                 }  
             }  
             $ENV{'form.alreadyHere'} = 1;  
         }  
               
         # Preprocessing: If we're inlining nav maps into the top-level display,  
         # make sure we show this map!  
         if ($inlineTopLevelMaps && ref($curRes) && $curRes->is_map &&   
             scalar(@{$mapStack}) == 1) {  
             if ($condition) {  
                 undef $filterHash{$curRes->map_pc()};  
             } else {  
                 $filterHash{$curRes->map_pc()} = 1;  
             }  
         }  
   
         $curRes = $mapIterator->next();  
     }  
       
     undef $res; # so we don't accidentally use it later  
     my $indentLevel = 0;  
     my $indentString = "<img src=\"/adm/lonIcons/whitespace1.gif\" width=\"25\" height=\"1\" alt=\"\" border=\"0\" />";  
   
     my $isNewBranch = 0;  
     my $now = time();  
     my $in24Hours = $now + 24 * 60 * 60;  
     my $displayedHereMarker = 0;  
       
     # We know the first thing is a BEGIN_MAP (see "$self->{STARTED}"  
     # code in iterator->next), so ignore the first one  
     $mapIterator = $navmap->getIterator(undef, undef, \%filterHash,  
                                            $condition);  
     $mapIterator->next();  
     $curRes = $mapIterator->next();  
     my $deltadepth = 0;  
     $depth = 1;  
   
     my @backgroundColors = ("#FFFFFF", "#F6F6F6");  
     my $rowNum = 0;  
   
     $counter = 0;  
   
     # Print the 'current' anchor here if it would fall off the top  
     if ($currentUrlIndex - $currentUrlDelta < 0) {  
         $r->print('<a name="current" />');  
     }  
   
     while ($depth > 0) {  
         # If this is an inlined map, cancel the shift to the right,  
         # which has the effect of making the map look inlined  
         if ($inlineTopLevelMaps && scalar(@{$mapIterator->getStack()}) == 1 &&  
             ref($curRes) && $curRes->is_map()) {  
             $deltadepth = -1;  
             $curRes = $mapIterator->next();  
             next;  
         }  
   
         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()) {  
             $isNewBranch = 1;  
         }  
         if ($curRes == $mapIterator->BEGIN_MAP()) { $depth++; }  
         if ($curRes == $mapIterator->END_MAP()) { $depth--; }  
   
         if (ref($curRes)) { $counter++; }  
   
         if ($depth == 1) { $deltadepth = 0; } # we're done shifting, because we're  
                                               # out of the inlined map  
   
         # Is this resource being ignored because it is in a random-out  
         # map and it was not selected?  
         if (ref($curRes) && !advancedUser() && $curRes->randomout()) {  
             $curRes = $mapIterator->next();  
             next; # if yes, then just ignore this resource  
         }  
   
         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")) {  
                         # no parts are open, display as one part  
                         @parts = ("0");  
                         $condensed = 1;  
                     } else {  
                         # Otherwise, only display part 0 if we want to   
                         # attach feedback or email information to it  
                         if ($curRes->hasDiscussion() || $curRes->getFeedback()) {  
                             shift @parts;  
                         } else {  
                             # 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 {  
                 $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, and it simplifies the looping  
             }  
   
             # Is it a multipart problem with a single part, now in   
             # @parts with "0" filtered out? If so, 'forget' it's a multi-part  
             # problem and treat it like a single-part problem.  
             if ( scalar(@parts) == 1 ) {  
                 $multipart = 0;  
             }  
   
             # Display one part, in event of network error.  
             # If this is a single part, we can at least show the correct  
             # status, but if it's multipart, we're lost, since we can't  
             # retreive the metadata to count the parts  
             if ($curRes->{RESOURCE_ERROR}) {  
                 @parts = ("0");  
             }  
   
             # Step Two: Print the actual data.  
   
             # For each part we intend to display...  
             foreach my $part (@parts) {  
   
                 my $deltalevel = 0; # for inserting the branch icon  
                 my $nonLinkedText = ""; # unlinked stuff after title  
                   
                 my $stack = $mapIterator->getStack();  
                 my $src = getLinkForResource($stack);  
   
                 # Pass the correct symb on the querystring, so the  
                 # remote will figure out where we are if we click a link  
                 my $srcHasQuestion = $src =~ /\?/;  
                 my $link = $src.  
                     ($srcHasQuestion?'&':'?') .  
                     'symb='.&Apache::lonnet::escape($curRes->symb()).  
                     '"';  
   
                 my $title = $curRes->title();  
                 if (!$title) {  
                     $title = $curRes->src();  
                     $title = substr ($title, rindex($title, "/") + 1);  
                 }  
                 my $partLabel = "";  
                 my $newBranchText = "";  
   
                 # If this is a new branch, label it so  
                 if ($isNewBranch) {  
                     $newBranchText = "<img src=\"/adm/lonIcons/branch.gif\" border=\"0\">";  
                     $isNewBranch = 0;  
                     $deltalevel = 1; # reserves space for the branch icon  
                 }  
   
                 # links to open and close the folders  
                 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  
                 if ($curRes->is_map()) {   
                     my $mapId = $curRes->map_pc();  
                     my $nowOpen = (!defined($filterHash{$mapId}));  
                     if ($condition) {$nowOpen = !$nowOpen;}  
                     $icon = $nowOpen ?  
                         "navmap.folder.closed.gif" : "navmap.folder.open.gif";  
                     $icon = "<img src=\"/adm/lonIcons/$icon\" alt=\"\" border=\"0\" />";  
                     $linkopen = "<a href=\"/adm/navmaps?filter=";  
                     $linkopen .= ($nowOpen xor $condition) ?   
                         addToFilter(\%filterHash, $mapId) :  
                         removeFromFilter(\%filterHash, $mapId);  
                     $linkopen .= "&condition=$condition&$queryAdd\">";  
                     $linkclose = "</a>";  
   
                 }  
                   
                 my $colorizer = "";  
                 my $color;  
                 if ($curRes->is_problem()) {  
                     my $status = $curRes->status($part);  
                     $color = $colormap{$status};  
   
                     # Special case in the navmaps: If in less then  
                     # 24 hours, give it a bit of urgency  
                     if (($status == $curRes->OPEN() || $status == $curRes->ATTEMPTED() ||  
                          $status == $curRes->TRIES_LEFT())  
                         && $curRes->duedate() &&  
                         $curRes->duedate() < time()+(24*60*60) &&   
                         $curRes->duedate() > time()) {  
                         $color = $hurryUpColor;  
                     }  
                     # Special case: If this is the last try, and there is  
                     # more then one available, and it's not due yet, give a bit of urgency  
                     my $tries = $curRes->tries($part);  
                     my $maxtries = $curRes->maxtries($part);  
                     if ($tries && $maxtries && $maxtries > 1 &&  
                         $maxtries - $tries == 1 && $curRes->duedate() &&  
                         $curRes->duedate() > time()) {  
                         $color = $hurryUpColor;  
                     }  
                     if ($color ne "") {  
                         $colorizer = "bgcolor=\"$color\"";  
                     }  
                 }  
   
                 if ($curRes->randomout()) {  
                     $nonLinkedText .= ' <i>(hidden)</i> ';  
                 }  
   
                 $rowNum++;  
                 my $backgroundColor = $backgroundColors[$rowNum % scalar(@backgroundColors)];  
   
                 # FIRST COL: The resource indentation, branch icon, name, and anchor  
                 $r->print("  <tr bgcolor=\"$backgroundColor\"><td align=\"left\" valign=\"center\" width=\"60%\">\n");  
   
                 # Print the anchor if necessary  
                 if ($counter == $currentUrlIndex - $currentUrlDelta) {  
                     $r->print('<a name="current" />');  
                 }  
   
                 # print indentation  
                 for (my $i = 0; $i < $indentLevel - $deltalevel + $deltadepth; $i++) {  
                     $r->print($indentString);  
                 }  
   
                 $r->print("  ${newBranchText}${linkopen}$icon${linkclose}\n");  
   
                 my $curMarkerBegin = "";  
                 my $curMarkerEnd = "";  
   
                 # Is this the current resource?  
                 if ($curRes->src() eq $currenturl && !$displayedHereMarker) {  
                     $curMarkerBegin = '<a name="curloc" /><font color="red" size="+2">&gt; </font>';  
                     $curMarkerEnd = '<font color="red" size="+2"> &lt;</font>';  
                     $displayedHereMarker = 1;  
                 }  
   
                 if ($curRes->is_problem() && $part ne "0" && !$condensed) {   
                     $partLabel = " (Part $part)";   
                     $title = "";  
                 }  
                 if ($multipart && $condensed) {  
                     $nonLinkedText .= ' (' . $curRes->countParts() . ' parts)';  
                 }  
   
                 $r->print("  $curMarkerBegin<a href=\"$link\">$title$partLabel</a> $curMarkerEnd $nonLinkedText");  
   
                 if ($curRes->{RESOURCE_ERROR}) {  
                     $r->print(&Apache::loncommon::help_open_topic ("Navmap_Host_Down",  
                                               '<font size="-1">Host down</font>'));  
                     }  
   
                 # SECOND COL: Is there text, feedback, errors??  
                 my $discussionHTML = ""; my $feedbackHTML = "";  
   
                 if ($curRes->hasDiscussion()) {  
                     $discussionHTML = $linkopen .  
                         '<img border="0" src="/adm/lonMisc/chat.gif" />' .  
                         $linkclose;  
                 }  
   
                 if ($curRes->getFeedback()) {  
                     my $feedback = $curRes->getFeedback();  
                     foreach (split(/\,/, $feedback)) {  
                         if ($_) {  
                             $feedbackHTML .= '&nbsp;<a href="/adm/email?display='  
                                 . &Apache::lonnet::escape($_) . '">'  
                                 . '<img src="/adm/lonMisc/feedback.gif" '  
                                 . 'border="0" /></a>';  
                         }  
                     }  
                 }  
   
                 $r->print("<td width=\"75\" align=\"left\" valign=\"center\">$discussionHTML$feedbackHTML&nbsp;</td>");  
   
                 # Is this the first displayed part of a multi-part problem  
                 # that has not been condensed, so we should suppress these two  
                 # columns so we don't display useless status info about part  
                 # "0"?  
                 my $firstDisplayed = !$condensed && $multipart && $part eq "0";  
   
                 # THIRD COL: Problem status icon  
                 if ($curRes->is_problem() &&  
                     !$firstDisplayed) {  
                     my $icon = $statusIconMap{$curRes->status($part)};  
                     my $alt = $iconAltTags{$icon};  
                     if ($icon) {  
                         $r->print("<td width=\"30\" valign=\"center\" width=\"50\" align=\"right\">$linkopen<img width=\"25\" height=\"25\" src=\"/adm/lonIcons/$icon\" border=\"0\" alt=\"$alt\" />$linkclose</td>\n");  
                     } else {  
                         $r->print("<td width=\"30\">&nbsp;</td>\n");  
                     }  
                 } else { # not problem, no icon  
                     $r->print("<td width=\"30\">&nbsp;</td>\n");  
                 }  
   
                 # FOURTH COL: Text description  
                 $r->print("<td align=\"right\" valign=\"center\">\n");  
                   
                 if ($curRes->kind() eq "res" &&  
                     $curRes->is_problem() &&  
                     !$firstDisplayed) {  
                     $r->print ("<font color=\"$color\"><b>") if ($color);  
                     $r->print (getDescription($curRes, $part));  
                     $r->print ("</b></font>") if ($color);  
                 }  
                 if ($curRes->is_map() && advancedUser() && $curRes->randompick()) {  
                     $r->print('(randomly select ' . $curRes->randompick() .')');  
                 }  
   
                 $r->print("&nbsp;</td></tr>\n");  
             }  
         }  
         $curRes = $mapIterator->next();  
     }  
   
     $r->print("</table></body></html>");  
   
     $navmap->untieHashes();  
   
     return OK;  
 }  }
   
 # Convenience functions: Returns a string that adds or subtracts  # Convenience functions: Returns a string that adds or subtracts
Line 651  sub removeFromFilter { Line 139  sub removeFromFilter {
   
 # Convenience function: Given a stack returned from getStack on the iterator,  # Convenience function: Given a stack returned from getStack on the iterator,
 # return the correct src() value.  # return the correct src() value.
 # Later, this should add an anchor when we start putting anchors in pages.  
 sub getLinkForResource {  sub getLinkForResource {
     my $stack = shift;      my $stack = shift;
     my $res;      my $res;
   
     # Check to see if there are any pages in the stack      # Check to see if there are any pages in the stack
     foreach $res (@$stack) {      foreach $res (@$stack) {
         if (defined($res) && $res->is_page()) {          if (defined($res)) {
             return $res->src();      my $anchor;
       if ($res->is_page()) {
    foreach my $item (@$stack) { if (defined($item)) { $anchor = $item; }  }
    $anchor=&escape($anchor->shown_symb());
    return ($res->link(),$res->shown_symb(),$anchor);
       }
               # in case folder was skipped over as "only sequence"
       my ($map,$id,$src)=&Apache::lonnet::decode_symb($res->symb());
       if ($map=~/\.page$/) {
    my $url=&Apache::lonnet::clutter($map);
    $anchor=&escape($src->shown_symb());
    return ($url,$res->shown_symb(),$anchor);
       }
         }          }
     }      }
   
Line 667  sub getLinkForResource { Line 166  sub getLinkForResource {
     # (when we first recurse on a map, it puts an undefined resource      # (when we first recurse on a map, it puts an undefined resource
     # on the bottom because $self->{HERE} isn't defined yet, and we      # on the bottom because $self->{HERE} isn't defined yet, and we
     # want the src for the map anyhow)      # want the src for the map anyhow)
     foreach (@$stack) {      foreach my $item (@$stack) {
         if (defined($_)) { $res = $_; }          if (defined($item)) { $res = $item; }
     }      }
   
     return $res->src();      if ($res) {
    return ($res->link(),$res->shown_symb());
       }
       return;
 }  }
   
 # Convenience function: This seperates the logic of how to create  # Convenience function: This separates the logic of how to create
 # the problem text strings ("Due: DATE", "Open: DATE", "Not yet assigned",  # the problem text strings ("Due: DATE", "Open: DATE", "Not yet assigned",
 # etc.) into a seperate function. It takes a resource object as the  # etc.) into a separate function. It takes a resource object as the
 # first parameter, and the part number of the resource as the second.  # 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.  # It's basically a big switch statement on the status of the resource.
   
Line 685  sub getDescription { Line 187  sub getDescription {
     my $part = shift;      my $part = shift;
     my $status = $res->status($part);      my $status = $res->status($part);
   
     if ($status == $res->NETWORK_FAILURE) { return ""; }      my $open = $res->opendate($part);
       my $due = $res->duedate($part);
       my $answer = $res->answerdate($part);
   
       if ($status == $res->NETWORK_FAILURE) { 
           return &mt("Having technical difficulties; please check status later"); 
       }
     if ($status == $res->NOTHING_SET) {      if ($status == $res->NOTHING_SET) {
         return "Not currently assigned.";          return &mt("Not currently assigned.");
     }      }
     if ($status == $res->OPEN_LATER) {      if ($status == $res->OPEN_LATER) {
         return "Open " . timeToHumanString($res->opendate($part));          return &mt("Open ") .timeToHumanString($open,'start');
     }      }
     if ($status == $res->OPEN) {      if ($status == $res->OPEN) {
         if ($res->duedate($part)) {          if ($due) {
             return "Due " . timeToHumanString($res->duedate($part));      if ($res->is_practice()) {
    return &mt("Closes ")."  " .timeToHumanString($due,'start');
       } else {
    return &mt("Due")."  " .timeToHumanString($due,'end');
       }
         } else {          } else {
             return "Open, no due date";              return &mt("Open, no due date");
         }          }
     }      }
     if ($status == $res->PAST_DUE_ANSWER_LATER) {      if ($status == $res->PAST_DUE_ANSWER_LATER) {
         return "Answer open " . timeToHumanString($res->answerdate($part));          return &mt("Answer open")." " .timeToHumanString($answer,'start');
     }      }
     if ($status == $res->PAST_DUE_NO_ANSWER) {      if ($status == $res->PAST_DUE_NO_ANSWER) {
         return "Was due " . timeToHumanString($res->duedate($part));   if ($res->is_practice()) {
     }      return &mt("Closed")." " . timeToHumanString($due,'start');
     if ($status == $res->ANSWER_OPEN) {   } else {
         return "Answer available";      return &mt("Was due")." " . timeToHumanString($due,'end');
    }
       }
       if (($status == $res->ANSWER_OPEN || $status == $res->PARTIALLY_CORRECT)
    && $res->handgrade($part) ne 'yes') {
           return &mt("Answer available");
     }      }
     if ($status == $res->EXCUSED) {      if ($status == $res->EXCUSED) {
         return "Excused by instructor";          return &mt("Excused by instructor");
     }      }
     if ($status == $res->ATTEMPTED) {      if ($status == $res->ATTEMPTED) {
         return "Not yet graded.";          return &mt("Answer submitted, not yet graded");
     }      }
     if ($status == $res->TRIES_LEFT) {      if ($status == $res->TRIES_LEFT) {
         my $tries = $res->tries($part);          my $tries = $res->tries($part);
         my $maxtries = $res->maxtries($part);          my $maxtries = $res->maxtries($part);
         my $triesString = "";          my $triesString = "";
         if ($tries && $maxtries) {          if ($tries && $maxtries) {
             $triesString = "<font size=\"-1\"><i>($tries of $maxtries tries used)</i></font>";              $triesString = '<font size="-1"><i>('.&mt('[_1] of [quant,_2,try,tries] used',$tries,$maxtries).')</i></font>';
             if ($maxtries > 1 && $maxtries - $tries == 1) {              if ($maxtries > 1 && $maxtries - $tries == 1) {
                 $triesString = "<b>$triesString</b>";                  $triesString = "<b>$triesString</b>";
             }              }
         }          }
         if ($res->duedate()) {          if ($due) {
             return "Due " . timeToHumanString($res->duedate($part)) .              return &mt("Due")." " . timeToHumanString($due,'end') .
                 " $triesString";                  " $triesString";
         } else {          } else {
             return "No due date $triesString";              return &mt("No due date")." $triesString";
         }          }
     }      }
       if ($status == $res->ANSWER_SUBMITTED) {
           return &mt('Answer submitted');
       }
 }  }
   
 # This puts a human-readable name on the ENV variable.  # Convenience function, so others can use it: Is the problem due in less than
   # 24 hours, and still can be done?
   
   sub dueInLessThan24Hours {
       my $res = shift;
       my $part = shift;
       my $status = $res->status($part);
   
       return ($status == $res->OPEN() ||
               $status == $res->TRIES_LEFT()) &&
       $res->duedate($part) && $res->duedate($part) < time()+(24*60*60) &&
       $res->duedate($part) > time();
   }
   
   # Convenience function, so others can use it: Is there only one try remaining for the
   # part, with more than one try to begin with, not due yet and still can be done?
   sub lastTry {
       my $res = shift;
       my $part = shift;
   
       my $tries = $res->tries($part);
       my $maxtries = $res->maxtries($part);
       return $tries && $maxtries && $maxtries > 1 &&
           $maxtries - $tries == 1 && $res->duedate($part) &&
           $res->duedate($part) > time();
   }
   
   # This puts a human-readable name on the env variable.
   
 sub advancedUser {  sub advancedUser {
     return $ENV{'user.adv'};      return $env{'request.role.adv'};
 }  }
   
   
Line 747  sub advancedUser { Line 295  sub advancedUser {
 # print "Answer available $timestring"  # print "Answer available $timestring"
 # Very, very, very, VERY English-only... goodness help a localizer on  # Very, very, very, VERY English-only... goodness help a localizer on
 # this func...  # this func...
   
   
 sub timeToHumanString {  sub timeToHumanString {
     my ($time) = @_;      my ($time,$type,$format) = @_;
   
     # zero, '0' and blank are bad times      # zero, '0' and blank are bad times
     if (!$time) {      if (!$time) {
         return 'never';          return &mt('never');
     }      }
       unless (&Apache::lonlocal::current_language()=~/^en/) {
    return &Apache::lonlocal::locallocaltime($time);
       } 
     my $now = time();      my $now = time();
   
     my @time = localtime($time);  
     my @now = localtime($now);  
   
     # Positive = future      # Positive = future
     my $delta = $time - $now;      my $delta = $time - $now;
   
Line 784  sub timeToHumanString { Line 334  sub timeToHumanString {
         my $tense = $inPast ? " ago" : "";          my $tense = $inPast ? " ago" : "";
         my $prefix = $inPast ? "" : "in ";          my $prefix = $inPast ? "" : "in ";
                   
         # Less then a minute          # Less than a minute
         if ( $delta < $minute ) {          if ( $delta < $minute ) {
             if ($delta == 1) { return "${prefix}1 second$tense"; }              if ($delta == 1) { return "${prefix}1 second$tense"; }
             return "$prefix$delta seconds$tense";              return "$prefix$delta seconds$tense";
         }          }
   
         # Less then an hour          # Less than an hour
         if ( $delta < $hour ) {          if ( $delta < $hour ) {
             # If so, use minutes              # If so, use minutes
             my $minutes = floor($delta / 60);              my $minutes = floor($delta / 60);
Line 798  sub timeToHumanString { Line 348  sub timeToHumanString {
             return "$prefix$minutes minutes$tense";              return "$prefix$minutes minutes$tense";
         }          }
                   
         # Is it less then 24 hours away? If so,          # Is it less than 24 hours away? If so,
         # display hours + minutes          # display hours + minutes
         if ( $delta < $hour * 24) {          if ( $delta < $hour * 24) {
             my $hours = floor($delta / $hour);              my $hours = floor($delta / $hour);
Line 817  sub timeToHumanString { Line 367  sub timeToHumanString {
             return "$prefix$hourString$minuteString$tense";              return "$prefix$hourString$minuteString$tense";
         }          }
   
         # Less then 5 days away, display day of the week and   my $dt = DateTime->from_epoch(epoch => $time)
                    ->set_time_zone(&Apache::lonlocal::gettimezone());
   
    # If there's a caller supplied format, use it.
   
    if ($format ne '') {
       my $timeStr = $dt->strftime($format);
       return $timeStr.' ('.$dt->time_zone_short_name().')';
    }
   
           # Less than 5 days away, display day of the week and
         # HH:MM          # HH:MM
   
         if ( $delta < $day * 5 ) {          if ( $delta < $day * 5 ) {
             my $timeStr = strftime("%A, %b %e at %I:%M %P", localtime($time));              my $timeStr = $dt->strftime("%A, %b %e at %I:%M %P (%Z)");
             $timeStr =~ s/12:00 am/midnight/;              $timeStr =~ s/12:00 am/00:00/;
             $timeStr =~ s/12:00 pm/noon/;              $timeStr =~ s/12:00 pm/noon/;
             return ($inPast ? "last " : "next ") .              return ($inPast ? "last " : "this ") .
                 $timeStr;                  $timeStr;
         }          }
                   
    my $conjunction='on';
    if ($type eq 'start') {
       $conjunction='at';
    } elsif ($type eq 'end') {
       $conjunction='by';
    }
         # Is it this year?          # Is it this year?
         if ( $time[5] == $now[5]) {   my $dt_now = DateTime->from_epoch(epoch => $now)
                        ->set_time_zone(&Apache::lonlocal::gettimezone());
           if ( $dt->year() == $dt_now->year()) {
             # Return on Month Day, HH:MM meridian              # Return on Month Day, HH:MM meridian
             my $timeStr = strftime("on %A, %b %e at %I:%M %P", localtime($time));              my $timeStr = $dt->strftime("$conjunction %A, %b %e at %I:%M %P (%Z)");
             $timeStr =~ s/12:00 am/midnight/;              $timeStr =~ s/12:00 am/00:00/;
             $timeStr =~ s/12:00 pm/noon/;              $timeStr =~ s/12:00 pm/noon/;
             return $timeStr;              return $timeStr;
         }          }
   
         # Not this year, so show the year          # Not this year, so show the year
         my $timeStr = strftime("on %A, %b %e %G at %I:%M %P", localtime($time));          my $timeStr = 
         $timeStr =~ s/12:00 am/midnight/;      $dt->strftime("$conjunction %A, %b %e %Y at %I:%M %P (%Z)");
           $timeStr =~ s/12:00 am/00:00/;
         $timeStr =~ s/12:00 pm/noon/;          $timeStr =~ s/12:00 pm/noon/;
         return $timeStr;          return $timeStr;
     }      }
 }  }
   
   
   =pod
   
   =head1 NAME
   
   Apache::lonnavmap - Subroutines to handle and render the navigation
       maps
   
   =head1 SYNOPSIS
   
   The main handler generates the navigational listing for the course,
   the other objects export this information in a usable fashion for
   other modules.
   
   =head1 OVERVIEW
   
   X<lonnavmaps, overview> When a user enters a course, LON-CAPA examines the
   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
   LON-CAPA, in a course, by going to /adm/test. (You may need to
   tweak the /home/httpd/lonTabs/htpasswd file to view it.) The
   content of the hash will be under the heading "Big Hash".
   
   Big Hash contains, among other things, how resources are related
   to each other (next/previous), what resources are maps, which 
   resources are being chosen to not show to the student (for random
   selection), and a lot of other things that can take a lot of time
   to compute due to the amount of data that needs to be collected and
   processed.
   
   Apache::lonnavmaps provides an object model for manipulating this
   information in a higher-level fashion than 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-
   resource sort of value, like whether there is any feedback on 
   a given resource.
   
   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 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.
   
   All other parameters are ways of either changing how the columns
   are printing, or which rows are shown.
   
   The pre-packaged column names are refered to by constants in the
   Apache::lonnavmaps namespace. The following currently exist:
   
   =over 4
   
   =item * B<Apache::lonnavmaps::resource>:
   
   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:
   
   =over 4
   
   =item * B<resource_nolink>: default false
   
   If true, the resource will not be linked. By default, all non-folder
   resources are linked.
   
   =item * B<resource_part_count>: default true
   
   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.
   
   =item * B<resource_no_folder_link>:
   
   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.
   
   =back
   
   =item * B<Apache::lonnavmaps::communication_status>:
   
   Whether there is discussion on the resource, email for the user, or
   (lumped in here) perl errors in the execution of the problem. This is
   the second column in the main nav map.
   
   =item * B<Apache::lonnavmaps::quick_status>:
   
   An icon for the status of a problem, with five possible states:
   Correct, incorrect, open, awaiting grading (for a problem where the
   computer's grade is suppressed, or the computer can't grade, like
   essay problem), or none (not open yet, not a problem). The
   third column of the standard navmap.
   
   =item * B<Apache::lonnavmaps::long_status>:
   
   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.
   
   =item * B<Apache::lonnavmaps::part_status_summary>:
   
   A text readout summarizing the status of the problem. If it is a
   single part problem, will display "Correct", "Incorrect", 
   "Not yet open", "Open", "Attempted", or "Error". If there are
   multiple parts, this will output a string that in HTML will show a
   status of how many parts are in each status, in color coding, trying
   to match the colors of the icons within reason.
   
   Note this only makes sense if you are I<not> showing parts. If 
   C<showParts> is true (see below), this column will not output
   anything. 
   
   =back
   
   If you add any others please be sure to document them here.
   
   An example of a column renderer that will show the ID number of a
   resource, along with the part name if any:
   
    sub { 
     my ($resource, $part, $params) = @_;   
     if ($part) { return '<td>' . $resource->{ID} . ' ' . $part . '</td>'; }
     return '<td>' . $resource->{ID} . '</td>';
    }
   
   Note these functions are responsible for the TD tags, which allow them
   to override vertical and horizontal alignment, etc.
   
   =head2 Parameters
   
   Minimally, you should be
   able to get away with just using 'cols' (to specify the columns
   shown), 'url' (necessary for the folders to link to the current screen
   correctly), and possibly 'queryString' if your app calls for it. In
   that case, maintaining the state of the folders will be done
   automatically.
   
   =over 4
   
   =item * B<iterator>: default: constructs one from %env
   
   A reference to a fresh ::iterator to use from the navmaps. The
   rendering will reflect the options passed to the iterator, so you can
   use that to just render a certain part of the course, if you like. If
   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.
   
   =item * B<iterator_map>: default: not used
   
   If you are letting the renderer do the iterator handling, you can
   instruct the renderer to render only a particular map by passing it
   the source of the map you want to process, like
   '/res/103/jerf/navmap.course.sequence'.
   
   =item * B<include_top_level_map>: default: false
   
   If you need to include the top level map (meaning the course) in the
   rendered output set this to true
   
   =item * B<navmap>: default: constructs one from %env
   
   A reference to a navmap, used only if an iterator is not passed in. If
   this is necessary to make an iterator but it is not passed in, a new
   one will be constructed based on env info. This is useful to do basic
   error checking before passing it off to render.
   
   =item * B<r>: default: must be passed in
   
   The standard Apache response object. This must be passed to the
   renderer or the course hash will be locked.
   
   =item * B<cols>: default: empty (useless)
   
   An array reference
   
   =item * B<showParts>:default true
   
   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
   resource will be displayed.
   
   =item * B<condenseParts>: default true
   
   A flag. If true, if all parts of the problem have the same
   status and that status is Nothing Set, Correct, or Network Failure,
   then only one line will be displayed for that resource anyhow. If no,
   all parts will always be displayed. If showParts is 0, this is
   ignored.
   
   =item * B<jumpCount>: default: determined from %env
   
   A string identifying the URL to place the anchor 'curloc' at.
   It is the responsibility of the renderer user to
   ensure that the #curloc is in the URL. By default, determined through
   the use of the env{} 'jump' information, and should normally "just
   work" correctly.
   
   =item * B<here>: default: empty string
   
   A Symb identifying where to place the 'here' marker. The empty
   string means no marker.
   
   =item * B<indentString>: default: 25 pixel whitespace image
   
   A string identifying the indentation string to use. 
   
   =item * B<queryString>: default: empty
   
   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.
   
   =item * B<url>: default: none
   
   The url the folders will link to, which should be the current
   page. Required if the resource info column is shown, and you 
   are allowing the user to open and close folders.
   
   =item * B<currentJumpIndex>: default: no jumping
   
   Describes the currently-open row number to cause the browser to jump
   to, because the user just opened that folder. By default, pulled from
   the Jump information in the env{'form.*'}.
   
   =item * B<printKey>: default: false
   
   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; }
   sub part_status_summary { return 4; }
   
   sub render_resource {
       my ($resource, $part, $params) = @_;
   
       my $nonLinkedText = ''; # stuff after resource title not in link
   
       my $link = $params->{"resourceLink"};
   
       #  The URL part is not escaped at this point, but the symb is... 
       #  The stuff to the left of the ? must have ' replaced by \' since
       #  it will be quoted with ' in the href.
   
       my ($left,$right) = split(/\?/, $link);
       $link = $left.'?'.$right;
   
       my $src = $resource->src();
       my $it = $params->{"iterator"};
       my $filter = $it->{FILTER};
   
       my $title = $resource->compTitle();
   
       my $partLabel = "";
       my $newBranchText = "";
       my $location=&Apache::loncommon::lonhttpdurl("/adm/lonIcons");
       # If this is a new branch, label it so
       if ($params->{'isNewBranch'}) {
           $newBranchText = "<img src='$location/branch.gif' border='0' alt='Branch' />";
       }
   
       # links to open and close the folder
   
       
       my $linkopen = "<a href=\"$link\">";
   
   
       my $linkclose = "</a>";
   
       # Default icon: unknown page
       my $icon = "<img src='$location/unknown.gif' alt='' border='0' alt='&nbsp;&nbsp;' ' />";
       
       if ($resource->is_problem()) {
           if ($part eq '0' || $params->{'condensed'}) {
       $icon = '<img src="'.$location.'/';
       if ($resource->is_task()) {
    $icon .= 'task.gif" alt="'.&mt('Task');
       } else {
    $icon .= 'problem.gif" alt="'.&mt('Problem');
       }
       $icon .='" border="0" />';
           } else {
               $icon = $params->{'indentString'};
           }
       } else {
    $icon = "<img src='".&Apache::loncommon::icon($resource->src)."' alt='&nbsp;&nbsp;' border='0' />";
       }
   
       # 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';
           my $title=$resource->title;
           $title=~s/\"/\&quot;/g;
           if (!$params->{'resource_no_folder_link'}) {
               $icon = "navmap.$folderType." . ($nowOpen ? 'closed' : 'open') . '.gif';
       $icon = "<img src='$location/$icon' alt=\"".
    ($nowOpen ? &mt('Open Folder') : &mt('Close Folder')).' '.$title."\" border='0' />";
   
               $linkopen = "<a href=\"" . $params->{'url'} . '?' . 
                   $params->{'queryString'} . '&amp;filter=';
               $linkopen .= ($nowOpen xor $it->{CONDITION}) ?
                   addToFilter($filter, $mapId) :
                   removeFromFilter($filter, $mapId);
               $linkopen .= "&amp;condition=" . $it->{CONDITION} . '&amp;hereType='
                   . $params->{'hereType'} . '&amp;here=' .
                   &escape($params->{'here'}) . 
                   '&amp;jump=' .
                   &escape($resource->symb()) . 
                   "&amp;folderManip=1\">";
   
           } else {
               # Don't allow users to manipulate folder
               $icon = "navmap.$folderType." . ($nowOpen ? 'closed' : 'open') .
                   '.nomanip.gif';
               $icon = "<img src='$location/$icon' alt=\"".
    ($nowOpen ? &mt('Open Folder') : &mt('Close Folder')).' '.$title."\" border='0' />";
   
               $linkopen = "";
               $linkclose = "";
           }
       }
   
       if ($resource->randomout()) {
           $nonLinkedText .= ' <i>('.&mt('hidden').')</i> ';
       }
       if (!$resource->condval()) {
           $nonLinkedText .= ' <i>('.&mt('conditionally hidden').')</i> ';
       }
       if (($resource->is_practice()) && ($resource->is_raw_problem())) {
           $nonLinkedText .=' <font color="green"><b>'.&mt('not graded').'</b></font>';
       }
    
       # We're done preparing and finally ready to start the rendering
       my $result = "<td align='left' valign='middle'>";
   
       my $indentLevel = $params->{'indentLevel'};
       if ($newBranchText) { $indentLevel--; }
   
       # 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'}) {
    my $displaypart=$resource->part_display($part);
           $partLabel = " (".&mt('Part: [_1]', $displaypart).")";
    if ($link!~/\#/) { $link.='#'.&escape($part); }
           $title = "";
       }
   
       if ($params->{'condensed'} && $resource->countParts() > 1) {
           $nonLinkedText .= ' ('.&mt('[_1] parts', $resource->countParts()).')';
       }
   
       my $target;
       if ($env{'environment.remotenavmap'} eq 'on') {
    $target=' target="loncapaclient" ';
       }
       if (!$params->{'resource_nolink'} && !$resource->is_sequence() && !$resource->is_empty_sequence) {
           $result .= "  $curMarkerBegin<a $target href=\"$link\">$title$partLabel</a>$curMarkerEnd $nonLinkedText</td>";
       } else {
           $result .= "  $curMarkerBegin$title$partLabel$curMarkerEnd $nonLinkedText</td>";
       }
   
       return $result;
   }
   
   sub render_communication_status {
       my ($resource, $part, $params) = @_;
       my $discussionHTML = ""; my $feedbackHTML = ""; my $errorHTML = "";
   
       my $link = $params->{"resourceLink"};
       my $target;
       if ($env{'environment.remotenavmap'} eq 'on') {
    $target=' target="loncapaclient" ';
       }
       my $linkopen = "<a $target href=\"$link\">";
       my $linkclose = "</a>";
       my $location=&Apache::loncommon::lonhttpdurl("/adm/lonMisc");
       if ($resource->hasDiscussion()) {
           $discussionHTML = $linkopen .
               '<img alt="'.&mt('New Discussion').'" border="0" src="'.$location.'/chat.gif" />' .
               $linkclose;
       }
       
       if ($resource->getFeedback()) {
           my $feedback = $resource->getFeedback();
           foreach my $msgid (split(/\,/, $feedback)) {
               if ($msgid) {
                   $feedbackHTML .= '&nbsp;<a '.$target.' href="/adm/email?display='
                       . &escape($msgid) . '">'
                       . '<img alt="'.&mt('New Email').'" src="'.$location.'/feedback.gif" '
                       . 'border="0" /></a>';
               }
           }
       }
       
       if ($resource->getErrors()) {
           my $errors = $resource->getErrors();
           my $errorcount = 0;
           foreach my $msgid (split(/,/, $errors)) {
               last if ($errorcount>=10); # Only output 10 bombs maximum
               if ($msgid) {
                   $errorcount++;
                   $errorHTML .= '&nbsp;<a '.$target.' href="/adm/email?display='
                       . &escape($msgid) . '">'
                       . '<img alt="'.&mt('New Error').'" src="'.$location.'/bomb.gif" '
                       . 'border="0" /></a>';
               }
           }
       }
   
       if ($params->{'multipart'} && $part != '0') {
    $discussionHTML = $feedbackHTML = $errorHTML = '';
       }
   
       return "<td width=\"75\" align=\"left\" valign=\"middle\">$discussionHTML$feedbackHTML$errorHTML&nbsp;</td>";
   
   }
   sub render_quick_status {
       my ($resource, $part, $params) = @_;
       my $result = "";
       my $firstDisplayed = !$params->{'condensed'} && 
           $params->{'multipart'} && $part eq "0";
   
       my $link = $params->{"resourceLink"};
       my $target;
       if ($env{'environment.remotenavmap'} eq 'on') {
    $target=' target="loncapaclient" ';
       }
       my $linkopen = "<a $target href=\"$link\">";
       my $linkclose = "</a>";
   
       if ($resource->is_problem() &&
           !$firstDisplayed) {
   
           my $icon = $statusIconMap{$resource->simpleStatus($part)};
           my $alt = $iconAltTags{$icon};
           if ($icon) {
       my $location=
    &Apache::loncommon::lonhttpdurl("/adm/lonIcons/$icon");
               $result .= "<td valign='middle' width='50' align='right'>$linkopen<img width='25' height='25' src='$location' border='0' alt='$alt' />$linkclose</td>\n";
           } else {
               $result .= "<td width='30'>&nbsp;</td>\n";
           }
       } else { # not problem, no icon
           $result .= "<td width='30'>&nbsp;</td>\n";
       }
   
       return $result;
   }
   sub render_long_status {
       my ($resource, $part, $params) = @_;
       my $result = "<td align='right' valign='middle'>\n";
       my $firstDisplayed = !$params->{'condensed'} && 
           $params->{'multipart'} && $part eq "0";
                   
       my $color;
       if ($resource->is_problem() || $resource->is_practice()) {
           $color = $colormap{$resource->status};
           
           if (dueInLessThan24Hours($resource, $part) ||
               lastTry($resource, $part)) {
               $color = $hurryUpColor;
           }
       }
       
       if ($resource->kind() eq "res" &&
           ($resource->is_problem() || $resource->is_practice()) &&
           !$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 .= &mt('(randomly select [_1])', $resource->randompick());
       }
       if ($resource->is_map() && &advancedUser() && $resource->randomorder()) {
           $result .= &mt('(randomly ordered)');
       }
   
       # Debugging code
       #$result .= " " . $resource->awarded($part) . '/' . $resource->weight($part) .
       # ' - Part: ' . $part;
   
       $result .= "</td>\n";
       
       return $result;
   }
   
   # Colors obtained by taking the icons, matching the colors, and
   # possibly reducing the Value (HSV) of the color, if it's too bright
   # for text, generally by one third or so.
   my %statusColors = 
       (
        $resObj->CLOSED => '#000000',
        $resObj->OPEN   => '#998b13',
        $resObj->CORRECT => '#26933f',
        $resObj->INCORRECT => '#c48207',
        $resObj->ATTEMPTED => '#a87510',
        $resObj->ERROR => '#000000'
        );
   my %statusStrings = 
       (
        $resObj->CLOSED => 'Not yet open',
        $resObj->OPEN   => 'Open',
        $resObj->CORRECT => 'Correct',
        $resObj->INCORRECT => 'Incorrect',
        $resObj->ATTEMPTED => 'Attempted',
        $resObj->ERROR => 'Network Error'
        );
   my @statuses = ($resObj->CORRECT, $resObj->ATTEMPTED, $resObj->INCORRECT, $resObj->OPEN, $resObj->CLOSED, $resObj->ERROR);
   
   sub render_parts_summary_status {
       my ($resource, $part, $params) = @_;
       if (!$resource->is_problem() && !$resource->contains_problem) { return '<td></td>'; }
       if ($params->{showParts}) { 
    return '<td></td>';
       }
   
       my $td = "<td align='right'>\n";
       my $endtd = "</td>\n";
       my @probs;
   
       if ($resource->contains_problem) {
    @probs=$resource->retrieveResources($resource,sub { $_[0]->is_problem() },1,0);
       } else {
    @probs=($resource);
       }
       my $return;
       my %overallstatus;
       my $totalParts;
       foreach my $resource (@probs) {
    # If there is a single part, just show the simple status
    if ($resource->singlepart()) {
       my $status = $resource->simpleStatus(${$resource->parts}[0]);
       $overallstatus{$status}++;
       $totalParts++;
       next;
    }
    # Now we can be sure the $part doesn't really matter.
    my $statusCount = $resource->simpleStatusCount();
    my @counts;
    foreach my $status (@statuses) {
       # decouple display order from the simpleStatusCount order
       my $slot = Apache::lonnavmaps::resource::statusToSlot($status);
       if ($statusCount->[$slot]) {
    $overallstatus{$status}+=$statusCount->[$slot];
    $totalParts+=$statusCount->[$slot];
       }
    }
       }
       $return.= $td . $totalParts . ' parts: ';
       foreach my $status (@statuses) {
    if ($overallstatus{$status}) {
       $return.="<font color='" . $statusColors{$status} .
    "'>" . $overallstatus{$status} . ' '
    . $statusStrings{$status} . "</font>";
    }
       }
       $return.= $endtd;
       return $return;
   }
   
   my @preparedColumns = (\&render_resource, \&render_communication_status,
                          \&render_quick_status, \&render_long_status,
          \&render_parts_summary_status);
   
   sub setDefault {
       my ($val, $default) = @_;
       if (!defined($val)) { return $default; }
       return $val;
   }
   
   sub cmp_title {
       my ($atitle,$btitle) = (lc($_[0]->compTitle),lc($_[1]->compTitle));
       $atitle=~s/^\s*//;
       $btitle=~s/^\s*//;
       return $atitle cmp $btitle;
   }
   
   sub render {
       my $args = shift;
       &Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING});
       my $result = '';
       # Configure the renderer.
       my $cols = $args->{'cols'};
       if (!defined($cols)) {
           # no columns, no nav maps.
           return '';
       }
       my $navmap;
       if (defined($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 $closeAllPages = setDefault($args->{'closeAllPages'}, 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 my $item (split(/\,/, $env{"form.filter"})) {
           if ($item) {
               $filterHash->{$item} = "1";
           }
       }
   
       # 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);};
       }
   
       my $condition = 0;
       if ($env{'form.condition'}) {
           $condition = 1;
       }
   
       if (!$env{'form.folderManip'} && !defined($args->{'iterator'})) {
           # Step 1: Check to see if we have a navmap
           if (!defined($navmap)) {
               $navmap = Apache::lonnavmaps::navmap->new();
       if (!defined($navmap)) {
    # no longer in course
    return '<span class="LC_error">'.&mt('No course selected').'</span><br />
                           <a href="/adm/roles">'.&mt('Select a course').'</a><br />';
       }
    }
   
           # 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'} ne '') {
               $here = $jump = &Apache::lonnet::symbclean($env{'form.postsymb'});
           } elsif ($env{'form.postdata'} ne '') {
               # 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);
    }
    if ($here eq '') {
       my $last;
       if (tie(my %hash,'GDBM_File',$env{'request.course.fn'}.'_symb.db',
                       &GDBM_READER(),0640)) {
    $last=$hash{'last_known'};
    untie(%hash);
       }
       if ($last) { $here = $jump = $last; }
    }
   
           # 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 ($here && ($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)) {
               $navmap = Apache::lonnavmaps::navmap->new();
               if (!defined($navmap)) {
                   # no longer in course
                   return '<span class="LC_error">'.&mt('No course selected').'</span><br />
                           <a href="/adm/roles">'.&mt('Select a course').'</a><br />';
               }
           }
   
           # 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, $condition,undef,$args->{'include_top_level_map'});
           }
       }
   
       # (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;
           }
       }
   
       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">';
           $result.='<tr><td align="right" valign="bottom">Key:&nbsp;&nbsp;</td>';
    my $location=&Apache::loncommon::lonhttpdurl("/adm/lonMisc");
           if ($navmap->{LAST_CHECK}) {
               $result .= 
                   '<img src="'.$location.'/chat.gif"> '.&mt('New discussion since').' '.
                   strftime("%A, %b %e at %I:%M %P", localtime($navmap->{LAST_CHECK})).
                   '</td><td align="center" valign="bottom">&nbsp;&nbsp;'.
                   '<img src="'.$location.'/feedback.gif"> '.&mt('New message (click to open)').'<p>'.
                   '</td>'; 
           } else {
               $result .= '<td align="center" valign="bottom">&nbsp;&nbsp;'.
                   '<img src="'.$location.'/chat.gif"> '.&mt('Discussions').'</td><td align="center" valign="bottom">'.
                   '&nbsp;&nbsp;<img src="'.$location.'/feedback.gif"> '.&mt('New message (click to open)').
                   '</td>'; 
           }
   
           $result .= '</tr></table>';
       }
   
       if ($printCloseAll && !$args->{'resource_no_folder_link'}) {
    my ($link,$text);
           if ($condition) {
       $link='"navmaps?condition=0&amp;filter=&amp;'.$queryString.
    '&here='.&escape($here).'"';
       $text='Close all folders';
           } else {
       $link='"navmaps?condition=1&amp;filter=&amp;'.$queryString.
    '&here='.&escape($here).'"';
       $text='Open all folders';
           }
    if ($args->{'caller'} eq 'navmapsdisplay') {
       &add_linkitem($args->{'linkitems'},'changefolder',
     'location.href='.$link,$text);
    } else {
       $result.='<a href='.$link.'>'.&mt($text).'</a>';
    }
           $result .= "\n";
       }
   
       # Check for any unread discussions in all resources.
       if ($args->{'caller'} eq 'navmapsdisplay') {
    &add_linkitem($args->{'linkitems'},'clearbubbles',
         'document.clearbubbles.submit()',
         'Mark all posts read');
    my $time=time;
    $result .= (<<END);
       <form name="clearbubbles" method="post" action="/adm/feedback">
    <input type="hidden" name="navurl" value="$ENV{'QUERY_STRING'}" />
    <input type="hidden" name="navtime" value="$time" />
   END
           if ($args->{'sort'} eq 'discussion') { 
       my $totdisc = 0;
       my $haveDisc = '';
       my @allres=$navmap->retrieveResources();
       foreach my $resource (@allres) {
    if ($resource->hasDiscussion()) {
       $haveDisc .= $resource->wrap_symb().':';
       $totdisc ++;
    }
       }
       if ($totdisc > 0) {
    $haveDisc =~ s/:$//;
    $result .= (<<END);
    <input type="hidden" name="navmaps" value="$haveDisc" />
       </form>
   END
               }
    }
    $result.='</form>';
       }
   
       if ($args->{'caller'} eq 'navmapsdisplay') {
           $result .= '<table><tr><td>'.
                      &Apache::loncommon::help_open_menu('Navigation Screen','Navigation_Screen',undef,'RAT').'</td>';
    if ($env{'environment.remotenavmap'} ne 'on') {
       $result .= '<td>&nbsp;</td>'; 
           } else {
       $result .= '</tr><tr>'; 
           }
    $result.=&show_linkitems($args->{'linkitems'});
           if ($args->{'sort_html'}) {
       if ($env{'environment.remotenavmap'} ne 'on') {
    $result.='<td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td>'.
       '<td align="right">'.$args->{'sort_html'}.'</td></tr>';
       } else {
    $result.='</tr><tr><td align="left"><br />'.
       $args->{'sort_html'}.'</td></tr>';
       }
    }
           $result .= '</table>';
       } elsif ($args->{'sort_html'}) { 
           $result.=$args->{'sort_html'}; 
       }
   
       $result .= "<br />\n";
       if ($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;    
       my $location=
    &Apache::loncommon::lonhttpdurl("/adm/lonIcons/whitespace1.gif");
       $args->{'indentString'} = setDefault($args->{'indentString'}, "<img src='$location' width='25' height='1' alt='&nbsp;&nbsp;' 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();
           }
       }
   
       my $displayedJumpMarker = 0;
       # Set up iteration.
       my $now = time();
       my $in24Hours = $now + 24 * 60 * 60;
       my $rownum = 0;
   
       # export "here" marker information
       $args->{'here'} = $here;
   
       $args->{'indentLevel'} = -1; # first BEGIN_MAP takes this to 0
       my @resources;
       my $code='';# sub { !(shift->is_map();) };
       if ($args->{'sort'} eq 'title') {
           my $oldFilterFunc = $filterFunc;
    my $filterFunc= 
       sub {
    my ($res)=@_;
    if ($res->is_map()) { return 0;}
    return &$oldFilterFunc($res);
       };
    @resources=$navmap->retrieveResources(undef,$filterFunc);
    @resources= sort { &cmp_title($a,$b) } @resources;
       } elsif ($args->{'sort'} eq 'duedate') {
    my $oldFilterFunc = $filterFunc;
    my $filterFunc= 
       sub {
    my ($res)=@_;
    if (!$res->is_problem()) { return 0;}
    return &$oldFilterFunc($res);
       };
    @resources=$navmap->retrieveResources(undef,$filterFunc);
    @resources= sort {
       if ($a->duedate ne $b->duedate) {
           return $a->duedate cmp $b->duedate;
       }
       my $value=&cmp_title($a,$b);
       return $value;
    } @resources;
       } elsif ($args->{'sort'} eq 'discussion') {
    my $oldFilterFunc = $filterFunc;
    my $filterFunc= 
       sub {
    my ($res)=@_;
    if (!$res->hasDiscussion() &&
       !$res->getFeedback() &&
       !$res->getErrors()) { return 0;}
    return &$oldFilterFunc($res);
       };
    @resources=$navmap->retrieveResources(undef,$filterFunc);
    @resources= sort { &cmp_title($a,$b) } @resources;
       } else {
    #unknow sort mechanism or default
    undef($args->{'sort'});
       }
   
   
       while (1) {
    if ($args->{'sort'}) {
       $curRes = shift(@resources);
    } else {
       $curRes = $it->next($closeAllPages);
    }
    if (!$curRes) { last; }
   
           # 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 ($condenseParts) { # do the condensation
                   if (!$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';
           }
   
    {
       my ($src,$symb,$anchor,$stack);
       if ($args->{'sort'}) {
    my $it = $navmap->getIterator(undef, undef, undef, 1);
    while ( my $res=$it->next()) {
       if (ref($res) &&
    $res->symb() eq  $curRes->symb()) { last; }
    }
    $stack=$it->getStack();
       } else {
    $stack=$it->getStack();
       }
       ($src,$symb,$anchor)=getLinkForResource($stack);
       if (defined($anchor)) { $anchor='#'.$anchor; }
       my $srcHasQuestion = $src =~ /\?/;
       $args->{"resourceLink"} = $src.
    ($srcHasQuestion?'&':'?') .
    'symb=' . &escape($symb).$anchor;
    }
           # 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};
   
               # 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()) {
    # 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>
   if (location.href.indexOf('#curloc')==-1) {
       setTimeout(\"location += '#curloc';\", 0)
   }
   </script>";
       }
   
       $result .= "</table>";
       
       if ($r) {
           $r->print($result);
           $result = "";
           $r->rflush();
       }
           
       return $result;
   }
   
   sub add_linkitem {
       my ($linkitems,$name,$cmd,$text)=@_;
       $$linkitems{$name}{'cmd'}=$cmd;
       $$linkitems{$name}{'text'}=&mt($text);
   }
   
   sub show_linkitems {
       my ($linkitems)=@_;
       my @linkorder = ("blank","launchnav","closenav","firsthomework",
        "everything","uncompleted","changefolder","clearbubbles");
       
       my $result .= (<<ENDBLOCK);
                 <td align="left">
   <script type="text/javascript">
       function changeNavDisplay () {
    var navchoice = document.linkitems.toplink[document.linkitems.toplink.selectedIndex].value;
   ENDBLOCK
       foreach my $link (@linkorder) {
    $result.= "if (navchoice == '$link') {".
       $linkitems->{$link}{'cmd'}."}\n";
       }
       $result.='}
                 </script>
                      <form name="linkitems" method="post">
                          <span class="LC_nobreak"><select name="toplink">'."\n";
       foreach my $link (@linkorder) {
    if (defined($linkitems->{$link})) {
       if ($linkitems->{$link}{'text'} ne '') {
    $result .= ' <option value="'.$link.'">'.
       $linkitems->{$link}{'text'}."</option>\n";
       }
    }
       }
       $result .= '</select>&nbsp;<input type="button" name="chgnav"
                      value="Go" onClick="javascript:changeNavDisplay()" />
                   </span></form></td>'."\n";
   
       return $result;
   }
   
 1;  1;
   
 package Apache::lonnavmaps::navmap;  package Apache::lonnavmaps::navmap;
   
 =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.
   
 =head1 navmap object: Encapsulating the compiled nav map  Generally, you'll use the navmap object in one of three basic ways.
   In order of increasing complexity and power:
   
 navmap is an object that encapsulates a compiled course map and provides a reasonable interface to it.  =over 4
   
   =item * C<$navmap-E<gt>getByX>, where X is B<Id>, B<Symb> or B<MapPc> and getResourceByUrl. 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 really 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 (see the B<getResourceByUrl>
       documentation for more details.)
   
   =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.
   
   =back
   
   =head2 Creation And Destruction
   
   To create a navmap object, use the following function:
   
   =over 4
   
 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.  =item * B<Apache::lonnavmaps::navmap-E<gt>new>():
   
 You must obtain resource objects through the navmap object.  Creates a new navmap object. Returns the navmap object if this is
   successful, or B<undef> if not.
   
   =back
   
 =head2 Methods  =head2 Methods
   
 =over 4  =over 4
   
 =item * B<new>(navHashFile, parmHashFile, genCourseAndUserOptions, genMailDiscussStatus): Binds a new navmap object to the compiled nav map hash and parm hash given as filenames. 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
   
 use strict;  use strict;
 use GDBM_File;  use GDBM_File;
   use Apache::lonnet;
   use LONCAPA;
   
 sub new {  sub new {
     # magic invocation to create a class instance      # magic invocation to create a class instance
Line 879  sub new { Line 1841  sub new {
     my $class = ref($proto) || $proto;      my $class = ref($proto) || $proto;
     my $self = {};      my $self = {};
   
     $self->{NAV_HASH_FILE} = shift;  
     $self->{PARM_HASH_FILE} = shift;  
     $self->{GENERATE_COURSE_USER_OPT} = shift;  
     $self->{GENERATE_EMAIL_DISCUSS_STATUS} = shift;  
   
     # Resource cache stores navmap resources as we reference them. We generate      # Resource cache stores navmap resources 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 893  sub new { Line 1850  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} = {};
   
     bless($self);      bless($self);
                   
     return $self;      return $self;
 }  }
   
 sub init {  sub generate_course_user_opt {
     my $self = shift;      my $self = shift;
       if ($self->{COURSE_USER_OPT_GENERATED}) { return; }
   
     # If the course opt hash and the user opt hash should be generated,      my $uname=$env{'user.name'};
     # generate them      my $udom=$env{'user.domain'};
     if ($self->{GENERATE_COURSE_USER_OPT}) {      my $cid=$env{'request.course.id'};
         my $uname=$ENV{'user.name'};      my $cdom=$env{'course.'.$cid.'.domain'};
         my $udom=$ENV{'user.domain'};      my $cnum=$env{'course.'.$cid.'.num'};
         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) {      my $courseopt=&Apache::lonnet::get_courseresdata($cnum,$cdom);
                 my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum.      # Check for network failure
                                                  ':resourcedata',$chome);      if (!ref($courseopt)) {
                 if ($reply!~/^error\:/) {   if ( $courseopt =~ /no.such.host/i || $courseopt =~ /con_lost/i) {
                     $courserdatas{$cid}=$reply;      $self->{NETWORK_FAILURE} = 1;
                     $courserdatas{$cid.'.last_cache'}=time;   }
                 }   undef($courseopt);
                 # check to see if network failed      }
                 elsif ( $reply=~/no.such.host/i || $reply=~/con.*lost/i )  
                 {  
                     $self->{NETWORK_FAILURE} = 1;  
                 }  
             }  
             foreach (split(/\&/,$courserdatas{$cid})) {  
                 my ($name,$value)=split(/\=/,$_);  
                 $courseopt{$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) {  
                 my $reply=&Apache::lonnet::reply('dump:'.$udom.':'.$uname.':resourcedata',$uhome);      my $useropt=&Apache::lonnet::get_userresdata($uname,$udom);
                 if ($reply!~/^error\:/) {      # Check for network failure
                     $userrdatas{$uname.'___'.$udom}=$reply;      if (!ref($useropt)) {
                     $userrdatas{$uname.'___'.$udom.'.last_cache'}=time;   if ( $useropt =~ /no.such.host/i || $useropt =~ /con_lost/i) {
                 }      $self->{NETWORK_FAILURE} = 1;
                 # check to see if network failed   }
                 elsif ( $reply=~/no.such.host/i || $reply=~/con.*lost/i )   undef($useropt);
                 {      }
                     $self->{NETWORK_FAILURE} = 1;  
                 }      $self->{COURSE_OPT} = $courseopt;
       $self->{USER_OPT} = $useropt;
   
       $self->{COURSE_USER_OPT_GENERATED} = 1;
       
       return;
   }
   
   sub generate_email_discuss_status {
       my $self = shift;
       my $symb = shift;
       if ($self->{EMAIL_DISCUSS_GENERATED}) { return; }
   
       my $cid=$env{'request.course.id'};
       my $cdom=$env{'course.'.$cid.'.domain'};
       my $cnum=$env{'course.'.$cid.'.num'};
       
       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, $cnum);
       my %lastread = &Apache::lonnet::dump('nohist_'.$cid.'_discuss',
                                           $env{'user.domain'},$env{'user.name'},'lastread');
       my %lastreadtime = ();
       foreach my $key (keys %lastread) {
           my $shortkey = $key;
           $shortkey =~ s/_lastread$//;
           $lastreadtime{$shortkey} = $lastread{$key};
       }
   
       my %feedback=();
       my %error=();
       my @keys = &Apache::lonnet::getkeys('nohist_email',$env{'user.domain'},
    $env{'user.name'});
       
       foreach my $msgid (@keys) {
    if ((!$emailstatus{$msgid}) || ($emailstatus{$msgid} eq 'new')) {
               my ($sendtime,$shortsubj,$fromname,$fromdomain,$status,$fromcid,
                   $symb,$error) = &Apache::lonmsg::unpackmsgid($msgid);
               &Apache::lonenc::check_decrypt(\$symb); 
               if (($fromcid ne '') && ($fromcid ne $cid)) {
                   next;
             }              }
             foreach (split(/\&/,$userrdatas{$uname.'___'.$udom})) {              if (defined($symb)) {
                 my ($name,$value)=split(/\=/,$_);                  if (defined($error) && $error == 1) {
                 $useropt{$userprefix.&Apache::lonnet::unescape($name)}=                      $error{$symb}.=','.$msgid;
                     &Apache::lonnet::unescape($value);                  } else {
             }                      $feedback{$symb}.=','.$msgid;
             $self->{COURSE_OPT} = \%courseopt;  
             $self->{USER_OPT} = \%useropt;  
         }  
     }     
   
     if ($self->{GENERATE_EMAIL_DISCUSS_STATUS}) {  
         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}='';   
                 }                  }
                               } else {
                 if (($status{$msgid} eq 'new') ||                   my $plain=
                     (!$status{$msgid})) {                       &LONCAPA::unescape(&LONCAPA::unescape($msgid));
                     if ($what eq 'Error') {                  if ($plain=~/ \[([^\]]+)\]\:/) {
                         $error{$url}.=','.$msgid;                       my $url=$1;
                       if ($plain=~/\:Error \[/) {
                           $error{$url}.=','.$msgid;
                     } else {                      } else {
                         $feedback{$url}.=','.$msgid;                          $feedback{$url}.=','.$msgid;
                     }                      }
                 }                  }
             }              }
         }   }
               }
         $self->{FEEDBACK} = \%feedback;      
         $self->{ERROR_MSG} = \%error; # what is this? JB      #symbs of resources that have feedbacks (will be urls pre-2.3)
         $self->{DISCUSSION_TIME} = \%discussiontime;      $self->{FEEDBACK} = \%feedback;
         $self->{EMAIL_STATUS} = \%emailstatus;      #or errors (will be urls pre 2.3)
               $self->{ERROR_MSG} = \%error;
     }          $self->{DISCUSSION_TIME} = \%discussiontime;
       $self->{EMAIL_STATUS} = \%emailstatus;
       $self->{LAST_READ} = \%lastreadtime;
       
       $self->{EMAIL_DISCUSS_GENERATED} = 1;
   }
   
     $self->{PARM_CACHE} = {};  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;
 }  }
   
   sub get_discussion_data {
       my $self = shift;
       if ($self->{RETRIEVED_DISCUSSION_DATA}) {
    return $self->{DISCUSSION_DATA};
       }
   
       $self->generate_email_discuss_status();    
   
       my $cid=$env{'request.course.id'};
       my $cdom=$env{'course.'.$cid.'.domain'};
       my $cnum=$env{'course.'.$cid.'.num'};
       # Retrieve discussion data for resources in course
       my %discussion_data = &Apache::lonnet::dumpstore($cid,$cdom,$cnum);
   
   
       $self->{DISCUSSION_DATA} = \%discussion_data;
       $self->{RETRIEVED_DISCUSSION_DATA} = 1;
       return $self->{DISCUSSION_DATA};
   }
   
   
   # 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;
 }  }
   
 sub getIterator {  sub getIterator {
     my $self = shift;      my $self = shift;
     my $iterator = Apache::lonnavmaps::iterator->new($self, shift, shift,      my $iterator = Apache::lonnavmaps::iterator->new($self, shift, shift,
                                                      shift, undef, shift);                                                       shift, undef, shift,
        shift, shift);
     return $iterator;      return $iterator;
 }  }
   
 # unties the hash when done  # Private method: Does the given resource (as a symb string) have
 sub untieHashes {  # current discussion? Returns 0 if chat/mail data not extracted.
   sub hasDiscussion {
     my $self = shift;      my $self = shift;
     untie %{$self->{NAV_HASH}} if ($self->{HASH_TIED});      my $symb = shift;
     untie %{$self->{PARM_HASH}} if ($self->{HASH_TIED});      $self->generate_email_discuss_status();
     $self->{HASH_TIED} = 0;  
       if (!defined($self->{DISCUSSION_TIME})) { return 0; }
   
       #return defined($self->{DISCUSSION_TIME}->{$symb});
   
       # backward compatibility (bulletin boards used to be 'wrapped')
       my $ressymb = $self->wrap_symb($symb);
       if ( defined ( $self->{LAST_READ}->{$ressymb} ) ) {
           return $self->{DISCUSSION_TIME}->{$ressymb} > $self->{LAST_READ}->{$ressymb};
       } else {
   #        return $self->{DISCUSSION_TIME}->{$ressymb} >  $self->{LAST_CHECK}; # v.1.1 behavior 
           return $self->{DISCUSSION_TIME}->{$ressymb} >  0; # in 1.2 will display speech bubble icons for all items with posts until marked as read (even if read in v 1.1).
       }
 }  }
   
 # when the object is destroyed, be sure to untie all the hashes we tied.  sub last_post_time {
 sub DESTROY {  
     my $self = shift;      my $self = shift;
     $self->untieHashes();      my $symb = shift;
       my $ressymb = $self->wrap_symb($symb);
       return $self->{DISCUSSION_TIME}->{$ressymb};
 }  }
   
 # Private function: Does the given resource (as a symb string) have  sub discussion_info {
 # current discussion? Returns 0 if chat/mail data not extracted.  
 sub hasDiscussion {  
     my $self = shift;      my $self = shift;
     my $symb = shift;      my $symb = shift;
     if (!defined($self->{DISCUSSION_TIME})) { return 0; }      my $filter = shift;
   
       $self->get_discussion_data();
   
     return $self->{DISCUSSION_TIME}->{$symb} >      my $ressymb = $self->wrap_symb($symb);
            $self->{LAST_CHECK};      # keys used to store bulletinboard postings use 'unwrapped' symb. 
       my $discsymb = &escape($self->unwrap_symb($ressymb));
       my $version = $self->{DISCUSSION_DATA}{'version:'.$discsymb};
       if (!$version) { return; }
   
       my $prevread = $self->{LAST_READ}{$ressymb};
   
       my $count = 0;
       my $hiddenflag = 0;
       my $deletedflag = 0;
       my ($hidden,$deleted,%info);
   
       for (my $id=$version; $id>0; $id--) {
    my $vkeys=$self->{DISCUSSION_DATA}{$id.':keys:'.$discsymb};
    my @keys=split(/:/,$vkeys);
    if (grep(/^hidden$/ ,@keys)) {
       if (!$hiddenflag) {
    $hidden = $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':hidden'};
    $hiddenflag = 1;
       }
    } elsif (grep(/^deleted$/,@keys)) {
       if (!$deletedflag) {
    $deleted = $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':deleted'};
    $deletedflag = 1;
       }
    } else {
       if (($hidden !~/\.$id\./) && ($deleted !~/\.$id\./)) {
                   if ($filter eq 'unread') {
       if ($prevread >= $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':timestamp'}) {
                           next;
                       }
                   }
    $count++;
    $info{$count}{'subject'} =
       $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':subject'};
                   $info{$count}{'id'} = $id;
                   $info{$count}{'timestamp'} = $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':timestamp'};
               }
    }
       }
       if (wantarray) {
    return ($count,%info);
       }
       return $count;
 }  }
   
 # Private function: Does the given resource (as a symb string) have  sub wrap_symb {
       my $self = shift;
       my $symb = shift;
       if ($symb =~ m-___(adm/[^/]+/[^/]+/)(\d+)(/bulletinboard)$-) {
           unless ($symb =~ m|adm/wrapper/adm|) {
               $symb = 'bulletin___'.$2.'___adm/wrapper/'.$1.$2.$3;
           }
       }
       return $symb;
   }
   
   sub unwrap_symb {
       my $self = shift;
       my $ressymb = shift;
       my $discsymb = $ressymb;
       if ($ressymb =~ m-^(bulletin___\d+___)adm/wrapper/(adm/[^/]+/[^/]+/\d+/bulletinboard)$-) {
            $discsymb = $1.$2;
       }
       return $discsymb;
   }
   
   # 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;
       my $source = shift;
   
       $self->generate_email_discuss_status();
   
     if (!defined($self->{FEEDBACK})) { return ""; }      if (!defined($self->{FEEDBACK})) { return ""; }
           
     return $self->{FEEDBACK}->{$symb};      my $feedback;
       if ($self->{FEEDBACK}->{$symb}) {
           $feedback = $self->{FEEDBACK}->{$symb};
           if ($self->{FEEDBACK}->{$source}) {
               $feedback .= ','.$self->{FEEDBACK}->{$source};
           }
       } else {
           if ($self->{FEEDBACK}->{$source}) {
               $feedback = $self->{FEEDBACK}->{$source};
           }
       }
       return $feedback;
   }
   
   # Private method: Get the errors for that resource (by source).
   sub getErrors { 
       my $self = shift;
       my $symb = shift;
       my $src = shift;
   
       $self->generate_email_discuss_status();
   
       if (!defined($self->{ERROR_MSG})) { return ""; }
   
       my $errors;
       if ($self->{ERROR_MSG}->{$symb}) {
           $errors = $self->{ERROR_MSG}->{$symb};
           if ($self->{ERROR_MSG}->{$src}) {
               $errors .= ','.$self->{ERROR_MSG}->{$src};
           }
       } else {
           if ($self->{ERROR_MSG}->{$src}) {
               $errors = $self->{ERROR_MSG}->{$src};
           }
       }
       return $errors;
 }  }
   
 =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 than 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 1099  sub getById { Line 2241  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, $filename) = &Apache::lonnet::decode_symb($symb);
       my $map = $self->getResourceByUrl($mapUrl);
       my $returnvalue = undef;
       if (ref($map)) {
           $returnvalue = $self->getById($map->map_pc() .'.'.$id);
       }
       return $returnvalue;
   }
   
   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);
 }  }
   
Line 1132  sub finishResource { Line 2303  sub finishResource {
 # the actual lookup; parmval caches the results.  # the actual lookup; parmval caches the results.
 sub parmval {  sub parmval {
     my $self = shift;      my $self = shift;
     my ($what,$symb)=@_;      my ($what,$symb,$recurse)=@_;
     my $hashkey = $what."|||".$symb;      my $hashkey = $what."|||".$symb;
   
     if (defined($self->{PARM_CACHE}->{$hashkey})) {      if (defined($self->{PARM_CACHE}->{$hashkey})) {
         return $self->{PARM_CACHE}->{$hashkey};          if (ref($self->{PARM_CACHE}->{$hashkey}) eq 'ARRAY') { 
               if (defined($self->{PARM_CACHE}->{$hashkey}->[0])) {
                   if (wantarray) {
                       return @{$self->{PARM_CACHE}->{$hashkey}};
                   } else {
                       return $self->{PARM_CACHE}->{$hashkey}->[0];
                   }
               }
           } else {
               return $self->{PARM_CACHE}->{$hashkey};
           }
     }      }
       my $result = $self->parmval_real($what, $symb, $recurse);
     my $result = $self->parmval_real($what, $symb);  
     $self->{PARM_CACHE}->{$hashkey} = $result;      $self->{PARM_CACHE}->{$hashkey} = $result;
     return $result;      if (wantarray) {
           return @{$result};
       }
       return $result->[0];
 }  }
   
 sub parmval_real {  sub parmval_real {
     my $self = shift;      my $self = shift;
     my ($what,$symb) = @_;      my ($what,$symb,$recurse) = @_;
   
     my $cid=$ENV{'request.course.id'};      # Make sure the {USER_OPT} and {COURSE_OPT} hashes are populated
     my $csec=$ENV{'request.course.sec'};      $self->generate_course_user_opt();
     my $uname=$ENV{'user.name'};  
     my $udom=$ENV{'user.domain'};  
   
     unless ($symb) { return ''; }      my $cid=$env{'request.course.id'};
     my $result='';      my $csec=$env{'request.course.sec'};
       my $cgroup='';
       my @cgrps=split(/:/,$env{'request.course.groups'});
       if (@cgrps > 0) {
           @cgrps = sort(@cgrps);
           $cgroup = $cgrps[0];
       } 
       my $uname=$env{'user.name'};
       my $udom=$env{'user.domain'};
   
     my ($mapname,$id,$fn)=split(/\_\_\_/,$symb);      unless ($symb) { return ['']; }
       my $result='';
   
       my ($mapname,$id,$fn)=&Apache::lonnet::decode_symb($symb);
       $mapname = &Apache::lonnet::deversion($mapname);
 # ----------------------------------------------------- Cascading lookup scheme  # ----------------------------------------------------- Cascading lookup scheme
     my $rwhat=$what;      my $rwhat=$what;
     $what=~s/^parameter\_//;      $what=~s/^parameter\_//;
Line 1165  sub parmval_real { Line 2357  sub parmval_real {
   
     my $symbparm=$symb.'.'.$what;      my $symbparm=$symb.'.'.$what;
     my $mapparm=$mapname.'___(all).'.$what;      my $mapparm=$mapname.'___(all).'.$what;
     my $usercourseprefix=$uname.'_'.$udom.'_'.$cid;      my $usercourseprefix=$cid;
   
       my $grplevel=$usercourseprefix.'.['.$cgroup.'].'.$what;
       my $grplevelr=$usercourseprefix.'.['.$cgroup.'].'.$symbparm;
       my $grplevelm=$usercourseprefix.'.['.$cgroup.'].'.$mapparm;
   
     my $seclevel= $usercourseprefix.'.['.$csec.'].'.$what;      my $seclevel= $usercourseprefix.'.['.$csec.'].'.$what;
     my $seclevelr=$usercourseprefix.'.['.$csec.'].'.$symbparm;      my $seclevelr=$usercourseprefix.'.['.$csec.'].'.$symbparm;
Line 1181  sub parmval_real { Line 2377  sub parmval_real {
   
 # ---------------------------------------------------------- first, check user  # ---------------------------------------------------------- first, check user
     if ($uname and defined($useropt)) {      if ($uname and defined($useropt)) {
         if (defined($$useropt{$courselevelr})) { return $$useropt{$courselevelr}; }          if (defined($$useropt{$courselevelr})) { return [$$useropt{$courselevelr},'resource']; }
         if (defined($$useropt{$courselevelm})) { return $$useropt{$courselevelm}; }          if (defined($$useropt{$courselevelm})) { return [$$useropt{$courselevelm},'map']; }
         if (defined($$useropt{$courselevel})) { return $$useropt{$courselevel}; }          if (defined($$useropt{$courselevel})) { return [$$useropt{$courselevel},'course']; }
     }      }
   
 # ------------------------------------------------------- second, check course  # ------------------------------------------------------- second, check course
       if ($cgroup ne '' and defined($courseopt)) {
           if (defined($$courseopt{$grplevelr})) { return [$$courseopt{$grplevelr},'resource']; }
           if (defined($$courseopt{$grplevelm})) { return [$$courseopt{$grplevelm},'map']; }
           if (defined($$courseopt{$grplevel})) { return [$$courseopt{$grplevel},'course']; }
       }
   
     if ($csec and defined($courseopt)) {      if ($csec and defined($courseopt)) {
         if (defined($$courseopt{$seclevelr})) { return $$courseopt{$seclevelr}; }          if (defined($$courseopt{$seclevelr})) { return [$$courseopt{$seclevelr},'resource']; }
         if (defined($$courseopt{$seclevelm})) { return $$courseopt{$seclevelm}; }          if (defined($$courseopt{$seclevelm})) { return [$$courseopt{$seclevelm},'map']; }
         if (defined($$courseopt{$seclevel})) { return $$courseopt{$seclevel}; }          if (defined($$courseopt{$seclevel})) { return [$$courseopt{$seclevel},'course']; }
     }      }
   
     if (defined($courseopt)) {      if (defined($courseopt)) {
         if (defined($$courseopt{$courselevelr})) { return $$courseopt{$courselevelr}; }          if (defined($$courseopt{$courselevelr})) { return [$$courseopt{$courselevelr},'resource']; }
         if (defined($$courseopt{$courselevelm})) { return $$courseopt{$courselevelm}; }  
         if (defined($$courseopt{$courselevel})) { return $$courseopt{$courselevel}; }  
     }      }
   
 # ----------------------------------------------------- third, check map parms  # ----------------------------------------------------- third, check map parms
   
     my $thisparm=$$parmhash{$symbparm};      my $thisparm=$$parmhash{$symbparm};
     if (defined($thisparm)) { return $thisparm; }      if (defined($thisparm)) { return [$thisparm,'map']; }
   
 # ----------------------------------------------------- fourth , check default  # ----------------------------------------------------- fourth , check default
   
     my $default=&Apache::lonnet::metadata($fn,$rwhat.'.default');      my $meta_rwhat=$rwhat;
     if (defined($default)) { return $default}      $meta_rwhat=~s/\./_/g;
       my $default=&Apache::lonnet::metadata($fn,$meta_rwhat);
 # --------------------------------------------------- fifth , cascade up parts      if (defined($default)) { return [$default,'resource']}
       $default=&Apache::lonnet::metadata($fn,'parameter_'.$meta_rwhat);
       if (defined($default)) { return [$default,'resource']}
   # --------------------------------------------------- fifth, check more course
       if (defined($courseopt)) {
           if (defined($$courseopt{$courselevelm})) { return [$$courseopt{$courselevelm},'map']; }
           if (defined($$courseopt{$courselevel})) {
              my $ret = [$$courseopt{$courselevel},'course'];
              return $ret;
          }
       }
   # --------------------------------------------------- sixth , cascade up parts
   
     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($partgeneral[0])) { return \@partgeneral; }
             if (defined($resourcegeneral)) { return $resourcegeneral; }      }
       if ($recurse) { return []; }
       my $pack_def=&Apache::lonnet::packages_tab_default($fn,'resource.'.$rwhat);
       if (defined($pack_def)) { return [$pack_def,'resource']; }
       return [''];
   }
   
   =pod
   
   =item * B<getResourceByUrl>(url,multiple):
   
   Retrieves a resource object by URL of the resource, unless the optional
   multiple parameter is included in which case an array of resource 
   objects is returned. 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 (useful for maps), unless the multiple parameter has
   been included, in which case all instances are returned in an array.
   
   =item * B<retrieveResources>(map, filterFunc, recursive, bailout, showall):
   
   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. If showall is
   true it will not hide maps that contain nothing but one other map. 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,
   showall 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<hasResource>(map, filterFunc, recursive, showall):
   
   Convenience method for
   
    scalar(retrieveResources($map, $filterFunc, $recursive, 1, $showall)) > 0
   
   which will tell whether the map has resources matching the description
   in the filter function.
   
   =item * B<usedVersion>(url):
   
   Retrieves version infomation for a url. Returns the version (a number, or 
   the string "mostrecent") for resources which have version information in  
   the big hash.
       
   =cut
   
   
   sub getResourceByUrl {
       my $self = shift;
       my $resUrl = shift;
       my $multiple = shift;
   
       if (ref($resUrl)) { return $resUrl; }
   
       $resUrl = &Apache::lonnet::clutter($resUrl);
       my $resId = $self->{NAV_HASH}->{'ids_' . $resUrl};
       if (!$resId) { return ''; }
       if ($multiple) {
           my @resources = ();
           my @resIds = split (/,/, $resId);
           foreach my $id (@resIds) {
               my $resourceId = $self->getById($id);
               if ($resourceId) { 
                   push(@resources,$resourceId);
               }
         }          }
           return @resources;
       } else {
           if ($resId =~ /,/) {
               $resId = (split (/,/, $resId))[0];
           }
           return $self->getById($resId);
     }      }
     return '';  
 }  }
   
   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; }
       my $showall = shift;
       # Create the necessary iterator.
       if (!ref($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, $showall);
   
       my @resources = ();
   
       if (&$filterFunc($map)) {
    push(@resources, $map);
       }
   
       # 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 @resources;
   }
   
   sub hasResource {
       my $self = shift;
       my $map = shift;
       my $filterFunc = shift;
       my $recursive = shift;
       my $showall = shift;
       
       return scalar($self->retrieveResources($map, $filterFunc, $recursive, 1, $showall)) > 0;
   }
   
   sub usedVersion {
       my $self = shift;
       my $linkurl = shift;
       return $self->navhash("version_$linkurl");
   }
   
 1;  1;
   
 package Apache::lonnavmaps::iterator;  package Apache::lonnavmaps::iterator;
   use Scalar::Util qw(weaken);
   use Apache::lonnet;
   
 =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.  
   
 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:  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.
   
   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 1251  getIterator behaves as follows: Line 2627  getIterator behaves as follows:
   
 =over 4  =over 4
   
 =item * B<getIterator>(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(). 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.  =item * B<getIterator>(firstResource, finishResource, filterHash, condition, forceTop, returnTopMap):
   
 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.  All parameters are optional. firstResource is a resource reference
   corresponding to where the iterator should start. It defaults to
 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:  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 * BEGIN_MAP: A new map is being recursed into. This is returned I<after> the map resource itself is returned.  =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 * END_MAP: The map is now done.  =item * B<BEGIN_MAP>:
   
 =item * BEGIN_BRANCH: A branch is now starting. The next resource returned will be the first in that branch.  A new map is being recursed into. This is returned I<after> the map
   resource itself is returned.
   
 =item * END_BRANCH: The branch is now done.  =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_MAP.  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.
   
 =back  =back
   
   =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 than
   this. They should be migrated to this new style.
   
 =cut  =cut
   
 # Here are the tokens for the iterator:  # Here are the tokens for the iterator:
   
   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
Line 1295  sub new { Line 2742  sub new {
     my $class = ref($proto) || $proto;      my $class = ref($proto) || $proto;
     my $self = {};      my $self = {};
   
     $self->{NAV_MAP} = shift;      weaken($self->{NAV_MAP} = shift);
     return undef unless ($self->{NAV_MAP});      return undef unless ($self->{NAV_MAP});
   
     # Handle the parameters      # Handle the parameters
Line 1316  sub new { Line 2763  sub new {
     if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };      if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };
     $self->{CONDITION} = shift;      $self->{CONDITION} = shift;
   
       # 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      # 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.      # over the parts of the map we're going to look at.
   
Line 1331  sub new { Line 2786  sub new {
   
     my $maxDepth = 0; # tracks max depth      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) {      foreach my $pass (@iterations) {
         my $direction = $pass->[0];          my $direction = $pass->[0];
         my $valName = $pass->[1];          my $valName = $pass->[1];
Line 1344  sub new { Line 2809  sub new {
           
         # prime the recursion          # prime the recursion
         $self->{$firstResourceName}->{DATA}->{$valName} = 0;          $self->{$firstResourceName}->{DATA}->{$valName} = 0;
         my $depth = 0;   $iterator->next();
         $iterator->next();  
         my $curRes = $iterator->next();          my $curRes = $iterator->next();
         while ($depth > -1) {   my $depth = 1;
             if ($curRes == $iterator->BEGIN_MAP()) { $depth++; }          while ($depth > 0) {
             if ($curRes == $iterator->END_MAP()) { $depth--; }      if ($curRes == $iterator->BEGIN_MAP()) { $depth++; }
               if ($curRes == $iterator->END_MAP()) { $depth--; }
   
             if (ref($curRes)) {              if (ref($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 $resultingVal = $curRes->{DATA}->{$valName};
                 my $nextResources = $curRes->$nextResourceMethod();                  my $nextResources = $curRes->$nextResourceMethod();
                 my $resourceCount = scalar(@{$nextResources});                  my $nextCount = scalar(@{$nextResources});
               
                 if ($resourceCount == 1) {                  if ($nextCount == 1) { # **3**
                     my $current = $nextResources->[0]->{DATA}->{$valName} || 999999999;                      my $current = $nextResources->[0]->{DATA}->{$valName} || 999999999;
                     $nextResources->[0]->{DATA}->{$valName} = min($resultingVal, $current);                      $nextResources->[0]->{DATA}->{$valName} = min($resultingVal, $current);
                 }                  }
                                   
                 if ($resourceCount > 1) {                  if ($nextCount > 1) { # **4**
                     foreach my $res (@{$nextResources}) {                      foreach my $res (@{$nextResources}) {
                         my $current = $res->{DATA}->{$valName} || 999999999;                          my $current = $res->{DATA}->{$valName} || 999999999;
                         $res->{DATA}->{$valName} = min($current, $resultingVal + 1);                          $res->{DATA}->{$valName} = min($current, $resultingVal + 1);
Line 1369  sub new { Line 2841  sub new {
                 }                  }
             }              }
                           
             # Assign the final val              # Assign the final val (**2**)
             if (ref($curRes) && $direction == BACKWARD()) {              if (ref($curRes) && $direction == BACKWARD()) {
                 my $finalDepth = min($curRes->{DATA}->{TOP_DOWN_VAL},                  my $finalDepth = min($curRes->{DATA}->{TOP_DOWN_VAL},
                                      $curRes->{DATA}->{BOT_UP_VAL});                                       $curRes->{DATA}->{BOT_UP_VAL});
                                   
                 $curRes->{DATA}->{DISPLAY_DEPTH} = $finalDepth;                  $curRes->{DATA}->{DISPLAY_DEPTH} = $finalDepth;
                 if ($finalDepth > $maxDepth) {$maxDepth = $finalDepth;}                  if ($finalDepth > $maxDepth) {$maxDepth = $finalDepth;}
                 }              }
             $curRes = $iterator->next();  
       $curRes = $iterator->next();
         }          }
     }      }
   
       # Check: Was this only one resource, a map?
       if ($resourceCount == 1 && $resource->is_sequence() && !$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},
         $self->{FORCE_TOP});
           
       }
   
     # Set up some bookkeeping information.      # Set up some bookkeeping information.
     $self->{CURRENT_DEPTH} = 0;      $self->{CURRENT_DEPTH} = 0;
     $self->{MAX_DEPTH} = $maxDepth;      $self->{MAX_DEPTH} = $maxDepth;
     $self->{STACK} = [];      $self->{STACK} = [];
     $self->{RECURSIVE_ITERATOR_FLAG} = 0;      $self->{RECURSIVE_ITERATOR_FLAG} = 0;
       $self->{FINISHED} = 0; # When true, the iterator has finished
   
     for (my $i = 0; $i <= $self->{MAX_DEPTH}; $i++) {      for (my $i = 0; $i <= $self->{MAX_DEPTH}; $i++) {
         push @{$self->{STACK}}, [];          push @{$self->{STACK}}, [];
     }      }
   
     # Prime the recursion w/ the first resource      # Prime the recursion w/ the first resource **5**
     push @{$self->{STACK}->[0]}, $self->{FIRST_RESOURCE};      push @{$self->{STACK}->[0]}, $self->{FIRST_RESOURCE};
     $self->{ALREADY_SEEN}->{$self->{FIRST_RESOURCE}->{ID}} = 1;      $self->{ALREADY_SEEN}->{$self->{FIRST_RESOURCE}->{ID}} = 1;
   
Line 1402  sub new { Line 2889  sub new {
   
 sub next {  sub next {
     my $self = shift;      my $self = shift;
       my $closeAllPages=shift;
       if ($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->{RETURN_0} && !$self->{HAVE_RETURNED_0_BEGIN_MAP}) {
    $self->{HAVE_RETURNED_0_BEGIN_MAP} = 1;
    return $self->BEGIN_MAP();
       }
   
     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 = $self->{RECURSIVE_ITERATOR}->next($closeAllPages);
   
         # is it a begin or end map? If so, update the depth          # is it a begin or end map? If so, update the depth
         if ($next == BEGIN_MAP() ) { $self->{RECURSIVE_DEPTH}++; }          if ($next == BEGIN_MAP() ) { $self->{RECURSIVE_DEPTH}++; }
Line 1440  sub next { Line 2942  sub next {
     my $newDepth;      my $newDepth;
     my $here;      my $here;
     while ( $i >= 0 && !$found ) {      while ( $i >= 0 && !$found ) {
         if ( scalar(@{$self->{STACK}->[$i]}) > 0 ) {          if ( scalar(@{$self->{STACK}->[$i]}) > 0 ) { # **6**
             $here = $self->{HERE} = shift @{$self->{STACK}->[$i]};              $here = pop @{$self->{STACK}->[$i]}; # **7**
             $found = 1;              $found = 1;
             $newDepth = $i;              $newDepth = $i;
         }          }
Line 1455  sub next { Line 2957  sub next {
             $self->{CURRENT_DEPTH}--;              $self->{CURRENT_DEPTH}--;
             return END_BRANCH();              return END_BRANCH();
         } else {          } else {
       $self->{FINISHED} = 1;
             return END_MAP();              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      # Get to the right level
     if ( $self->{CURRENT_DEPTH} > $newDepth ) {      if ( $self->{CURRENT_DEPTH} > $newDepth ) {
         push @{$self->{STACK}->[$newDepth]}, $here;          push @{$self->{STACK}->[$newDepth]}, $here;
Line 1478  sub next { Line 2993  sub next {
     # So we need to look at all the resources 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      # categorize them if we haven't seen them, remember if we have a new
     my $nextUnfiltered = $here->getNext();      my $nextUnfiltered = $here->getNext();
       my $maxDepthAdded = -1;
       
     for (@$nextUnfiltered) {      for (@$nextUnfiltered) {
         if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) {          if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) {
             push @{$self->{STACK}->[$_->{DATA}->{DISPLAY_DEPTH}]}, $_;              my $depth = $_->{DATA}->{DISPLAY_DEPTH};
               push @{$self->{STACK}->[$depth]}, $_;
             $self->{ALREADY_SEEN}->{$_->{ID}} = 1;              $self->{ALREADY_SEEN}->{$_->{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 than 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      # That ends the main iterator logic. Now, do we want to recurse
     # down this map (if this resource is a map)?      # down this map (if this resource is a map)?
     if ($self->{HERE}->is_map() &&      if ( ($self->{HERE}->is_sequence() || (!$closeAllPages && $self->{HERE}->is_page())) &&
         (defined($self->{FILTER}->{$self->{HERE}->map_pc()}) xor $self->{CONDITION})) {          (defined($self->{FILTER}->{$self->{HERE}->map_pc()}) xor $self->{CONDITION})) {
         $self->{RECURSIVE_ITERATOR_FLAG} = 1;          $self->{RECURSIVE_ITERATOR_FLAG} = 1;
         my $firstResource = $self->{HERE}->map_start();          my $firstResource = $self->{HERE}->map_start();
Line 1497  sub next { Line 3030  sub next {
         $self->{RECURSIVE_ITERATOR} =           $self->{RECURSIVE_ITERATOR} = 
             Apache::lonnavmaps::iterator->new($self->{NAV_MAP}, $firstResource,              Apache::lonnavmaps::iterator->new($self->{NAV_MAP}, $firstResource,
                                               $finishResource, $self->{FILTER},                                                $finishResource, $self->{FILTER},
                                               $self->{ALREADY_SEEN}, $self->{CONDITION});                                                $self->{ALREADY_SEEN},
         $self->{CONDITION},
         $self->{FORCE_TOP});
       }
   
       # 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 $self->next($closeAllPages);
     }      }
   
     return $self->{HERE};      return $self->{HERE};
Line 1506  sub next { Line 3050  sub next {
   
 =pod  =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).  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  =cut
   
Line 1535  sub populateStack { Line 3085  sub populateStack {
 1;  1;
   
 package Apache::lonnavmaps::DFSiterator;  package Apache::lonnavmaps::DFSiterator;
   use Scalar::Util qw(weaken);
   use Apache::lonnet;
   
 # Not documented in the perldoc: This is a simple iterator that just walks  # 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  #  through the nav map and presents the resources in a depth-first search
Line 1543  package Apache::lonnavmaps::DFSiterator; Line 3095  package Apache::lonnavmaps::DFSiterator;
 #  useful for pre-processing of some kind, and is in fact used by the main  #  useful for pre-processing of some kind, and is in fact used by the main
 #  iterator that way, but that's about it.  #  iterator that way, but that's about it.
 # One could imagine merging this into the init routine of the main iterator,  # 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  #  but this might as well be left separate, since it is possible some other
 #  use might be found for it. - Jeremy  #  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 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 FORWARD { return 1; }      # go forward  sub FORWARD { return 1; }      # go forward
Line 1560  sub new { Line 3115  sub new {
     my $class = ref($proto) || $proto;      my $class = ref($proto) || $proto;
     my $self = {};      my $self = {};
   
     $self->{NAV_MAP} = shift;      weaken($self->{NAV_MAP} = shift);
     return undef unless ($self->{NAV_MAP});      return undef unless ($self->{NAV_MAP});
   
     $self->{FIRST_RESOURCE} = shift || $self->{NAV_MAP}->firstResource();      $self->{FIRST_RESOURCE} = shift || $self->{NAV_MAP}->firstResource();
Line 1577  sub new { Line 3132  sub new {
   
     # A hash, used as a set, of resource already seen      # A hash, used as a set, of resource already seen
     $self->{ALREADY_SEEN} = shift;      $self->{ALREADY_SEEN} = shift;
     if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };       if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };
     $self->{CONDITION} = shift;      $self->{CONDITION} = shift;
     $self->{DIRECTION} = shift || FORWARD();      $self->{DIRECTION} = shift || FORWARD();
   
Line 1659  sub next { Line 3214  sub next {
   
     # filter the next possibilities to remove things we've       # filter the next possibilities to remove things we've 
     # already seen.      # already seen.
     foreach (@$nextUnfiltered) {      foreach my $item (@$nextUnfiltered) {
         if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) {          if (!defined($self->{ALREADY_SEEN}->{$item->{ID}})) {
             push @$next, $_;              push @$next, $item;
         }          }
     }      }
   
Line 1686  sub next { Line 3241  sub next {
     return $self->{HERE};      return $self->{HERE};
 }  }
   
 1;  # 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.
 package Apache::lonnavmaps::resource;  
   
 use Apache::lonnet;  sub getStack {
       my $self=shift;
   
 =pod      my @stack;
   
 =head1 Object: resource      $self->populateStack(\@stack);
   
 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.      return \@stack;
   }
   
 A resource only makes sense in the context of a navmap, as some of the data is stored in the navmap object.  # Private method: Calls the iterators recursively to populate the stack.
   sub populateStack {
       my $self=shift;
       my $stack = shift;
   
 You will probably never need to instantiate this object directly. Use Apache::lonnavmap::navmap, and use the "start" method to obtain the starting resource.      push @$stack, $self->{HERE} if ($self->{HERE});
   
 =head2 Public Members      if ($self->{RECURSIVE_ITERATOR_FLAG}) {
           $self->{RECURSIVE_ITERATOR}->populateStack($stack);
       }
   }
   
 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.  1;
   
 =head2 Methods  package Apache::lonnavmaps::resource;
   use Scalar::Util qw(weaken);
   use Apache::lonnet;
   
 =over 4  =pod
   
 =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. Very rarely, if ever, called directly. Use the nav map->getByID() method.  =head1 Object: resource 
   
 =back  X<resource, navmap object>
   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::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 than resource IDs.
   
 =cut  =cut
   
Line 1722  sub new { Line 3351  sub new {
     my $class = ref($proto) || $proto;      my $class = ref($proto) || $proto;
     my $self = {};      my $self = {};
   
     $self->{NAV_MAP} = shift;      weaken($self->{NAV_MAP} = shift);
     $self->{ID} = shift;      $self->{ID} = shift;
   
     # Store this new resource in the parent nav map's cache.      # Store this new resource in the parent nav map's cache.
Line 1746  sub navHash { Line 3375  sub navHash {
     my $self = shift;      my $self = shift;
     my $param = shift;      my $param = shift;
     my $id = shift;      my $id = shift;
     return $self->{NAV_MAP}->{NAV_HASH}->{$param . ($id?$self->{ID}:"")};      return $self->{NAV_MAP}->navhash($param . ($id?$self->{ID}:""));
 }  }
   
 =pod  =pod
   
 B<Metadata Retreival>  =head2 Methods
   
   Once you have a resource object, here's what you can do with it:
   
   =head3 Attribute Retrieval
   
 These are methods that help you retrieve metadata about the resource: Method names are based on the fields in the compiled course representation.  Every resource has certain attributes that can be retrieved and used:
   
 =over 4  =over 4
   
 =item * B<ext>: Returns true if the resource is external.  =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<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 the number of randomly picked items for a map if the randompick
   feature is being used on the map. 
   
 =item * B<goesto>: Returns the "goesto" value from the compiled nav map. (It is likely you want to use B<getNext> instead.)  =item * B<randomorder>:
   
 =item * B<kind>: Returns the kind of the resource from the compiled nav map.  Returns true for a map if the randomorder feature is being used on the
   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<src>:
   
 =item * B<randompick>: Returns true for a map if the randompick feature is being used on the map. (?)  Returns the source for the resource.
   
 =item * B<src>: Returns the source for the resource.  =item * B<symb>:
   
 =item * B<symb>: Returns the symb for the resource.  Returns the symb for the resource.
   
 =item * B<title>: Returns the title of the resource.  =item * B<title>:
   
 =item * B<to>: Returns the "to" value from the compiled nav map. (It is likely you want to use B<getNext> instead.)  Returns the title of the resource.
   
 =back  =back
   
Line 1782  These are methods that help you retrieve Line 3444  These are methods that help you retrieve
 # 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 comesfrom { my $self=shift; return $self->navHash("comesfrom_", 1); }  sub comesfrom { my $self=shift; return $self->navHash("comesfrom_", 1); }
   sub encrypted { my $self=shift; return $self->navHash("encrypted_", 1); }
 sub ext { my $self=shift; return $self->navHash("ext_", 1) eq 'true:'; }  sub ext { my $self=shift; return $self->navHash("ext_", 1) eq 'true:'; }
 sub from { my $self=shift; return $self->navHash("from_", 1); }  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); }
 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 randomout { my $self=shift; return $self->navHash("randomout_", 1); }
 sub randompick {   sub randompick { 
     my $self = shift;      my $self = shift;
     return $self->{NAV_MAP}->{PARM_HASH}->{$self->symb .      my $randompick = $self->parmval('randompick');
                                                '.0.parameter_randompick'};      return $randompick;
   }
   sub randomorder { 
       my $self = shift;
       my $randomorder = $self->parmval('randomorder');
       return ($randomorder =~ /^yes$/i);
   }
   sub link {
       my $self=shift;
       if ($self->encrypted()) { return &Apache::lonenc::encrypted($self->src); }
       return $self->src;
 }  }
 sub src {   sub src { 
     my $self=shift;      my $self=shift;
     return $self->navHash("src_", 1);      return $self->navHash("src_", 1);
 }  }
   sub shown_symb {
       my $self=shift;
       if ($self->encrypted()) {return &Apache::lonenc::encrypted($self->symb());}
       return $self->symb();
   }
   sub id {
       my $self=shift;
       return $self->{ID};
   }
   sub enclosing_map_src {
       my $self=shift;
       (my $first, my $second) = $self->{ID} =~ /(\d+).(\d+)/;
       return $self->navHash('map_id_'.$first);
   }
 sub symb {  sub symb {
     my $self=shift;      my $self=shift;
     (my $first, my $second) = $self->{ID} =~ /(\d+).(\d+)/;      (my $first, my $second) = $self->{ID} =~ /(\d+).(\d+)/;
     my $symbSrc = &Apache::lonnet::declutter($self->src());      my $symbSrc = &Apache::lonnet::declutter($self->src());
     return &Apache::lonnet::declutter(      my $symb = &Apache::lonnet::declutter($self->navHash('map_id_'.$first)) 
          $self->navHash('map_id_'.$first))   
         . '___' . $second . '___' . $symbSrc;          . '___' . $second . '___' . $symbSrc;
       return &Apache::lonnet::symbclean($symb);
   }
   sub wrap_symb {
       my $self = shift;
       return $self->{NAV_MAP}->wrap_symb($self->symb());
 }  }
 sub title { my $self=shift; return $self->navHash("title_", 1); }  sub title { 
       my $self=shift; 
       if ($self->{ID} eq '0.0') {
    # 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 to { my $self=shift; return $self->navHash("to_", 1); }
   sub condition {
       my $self=shift;
       my $undercond=$self->navHash("undercond_", 1);
       if (!defined($undercond)) { return 1; };
       my $condid=$self->navHash("condid_$undercond");
       if (!defined($condid)) { return 1; };
       my $condition=&Apache::lonnet::directcondval($condid);
       return $condition;
   }
   sub condval {
       my $self=shift;
       my ($pathname,$filename) = 
    &Apache::lonnet::split_uri_for_cond($self->src());
   
       my $match=($env{'acc.res.'.$env{'request.course.id'}.'.'.$pathname}=~
          /\&\Q$filename\E\:([\d\|]+)\&/);
       if ($match) {
    return &Apache::lonnet::condval($1);
       }
       return 0;
   }
   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  =pod
   
Line 1815  These methods are shortcuts to deciding Line 3546  These methods are shortcuts to deciding
   
 =over 4  =over 4
   
 =item * B<is_map>: Returns true if the resource is a map type.  =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_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>:
   
 =item * B<is_page>: Returns true if the resource is a page.  Returns true if the resource is a page.
   
 =item * B<is_problem>: Returns true if the resource is a problem.  =item * B<is_sequence>:
   
 =item * B<is_sequence>: Returns true if the resource is a sequence.  Returns true if the resource is a sequence.
   
 =back  =back
   
 =cut  =cut
   
   sub hasResource {
      my $self = shift;
      return $self->{NAV_MAP}->hasResource(@_);
   }
   
   sub retrieveResources {
      my $self = shift;
      return $self->{NAV_MAP}->retrieveResources(@_);
   }
   
   sub is_exam {
       my ($self,$part) = @_;
       my $type = $self->parmval('type',$part);
       if ($type eq 'exam') {
           return 1;
       }
       if ($self->src() =~ /\.(exam)$/) {
           return 1;
       }
       return 0;
   }
 sub is_html {  sub is_html {
     my $self=shift;      my $self=shift;
     my $src = $self->src();      my $src = $self->src();
Line 1839  sub is_map { my $self=shift; return defi Line 3598  sub is_map { my $self=shift; return defi
 sub is_page {  sub is_page {
     my $self=shift;      my $self=shift;
     my $src = $self->src();      my $src = $self->src();
     return ($src =~ /page$/);      return $self->navHash("is_map_", 1) && 
    $self->navHash("map_type_" . $self->map_pc()) eq 'page';
   }
   sub is_practice {
       my $self=shift;
       my ($part) = @_;
       my $type = $self->parmval('type',$part);
       if ($type eq 'practice') {
           return 1;
       }
       return 0;
 }  }
 sub is_problem {  sub is_problem {
     my $self=shift;      my $self=shift;
     my $src = $self->src();      my $src = $self->src();
     return ($src =~ /problem$/);      if ($src =~ /\.(problem|exam|quiz|assess|survey|form|library|task)$/) {
    return !($self->is_practice());
       }
       return 0;
   }
   sub is_raw_problem {
       my $self=shift;
       my $src = $self->src();
       if ($src =~ /\.(problem|exam|quiz|assess|survey|form|library|task)$/) {
           return 1;
       }
       return 0;
   }
   
   sub contains_problem {
       my $self=shift;
       if ($self->is_page()) {
    my $hasProblem=$self->hasResource($self,sub { $_[0]->is_problem() },1);
    return $hasProblem;
       }
       return 0;
   }
   sub map_contains_problem {
       my $self=shift;
       if ($self->is_map()) {
    my $has_problem=
       $self->hasResource($self,sub { $_[0]->is_problem() },1);
    return $has_problem;
       }
       return 0;
 }  }
 sub is_sequence {  sub is_sequence {
     my $self=shift;      my $self=shift;
       return $self->navHash("is_map_", 1) && 
    $self->navHash("map_type_" . $self->map_pc()) eq 'sequence';
   }
   sub is_survey {
       my $self = shift();
       my $part = shift();
       my $type = $self->parmval('type',$part);
       if ($type eq 'survey') {
           return 1;
       }
       if ($self->src() =~ /\.(survey)$/) {
           return 1;
       }
       return 0;
   }
   sub is_task {
       my $self=shift;
       my $src = $self->src();
       return ($src =~ /\.(task)$/)
   }
   
   sub is_empty_sequence {
       my $self=shift;
     my $src = $self->src();      my $src = $self->src();
     return ($src =~ /sequence$/);      return !$self->is_page() && $self->navHash("is_map_", 1) && !$self->navHash("map_type_" . $self->map_pc());
 }  }
   
 # Private method: Shells out to the parmval in the nav map, handler parts.  # Private method: Shells out to the parmval in the nav map, handler parts.
 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());
 }  }
   
Line 1864  sub parmval { Line 3688  sub parmval {
   
 B<Map Methods>  B<Map Methods>
   
 These methods are useful for getting information about the map properties of the resource, if the resource is a map (B<is_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  =over 4
   
 =item * B<map_finish>: Returns a reference to a resource object corresponding to the finish resource of the map.  =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_pc>:
   
 =item * B<map_start>: Returns a reference to a resource object corresponding to the start resource of the map.  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_type>: Returns a string with the type of the map in it.  =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  =back
   
Line 1883  These methods are useful for getting inf Line 3721  These methods are useful for getting inf
 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;
Line 1895  sub map_pc { Line 3734  sub map_pc {
 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;
Line 1905  sub map_type { Line 3745  sub map_type {
     return $self->navHash("map_type_$pc", 0);      return $self->navHash("map_type_$pc", 0);
 }  }
   
   
   
 #####  #####
 # Property queries  # Property queries
 #####  #####
   
 # These functions will be responsible for returning the CORRECT  # These functions will be responsible for returning the CORRECT
 # VALUE for the parameter, no matter what. So while they may look  # VALUE for the parameter, no matter what. So while they may look
 # like direct calls to parmval, they can be more then that.  # like direct calls to parmval, they can be more than that.
 # So, for instance, the duedate function should use the "duedatetype"  # So, for instance, the duedate function should use the "duedatetype"
 # information, rather then the resource object user.  # information, rather than the resource object user.
   
 =pod  =pod
   
 =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 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>:
   
 =item * B<answerdate>: Get the answer-reveal date for the problem.  Get the answer-reveal date for the problem.
   
 =item * B<duedate>: Get the due date for the problem.  =item * B<awarded>: 
   
 =item * B<tries>: Get the number of tries the student has used on the problem.  Gets the awarded value for the problem part. Requires genUserData set to
   true when the navmap object was created.
   
 =item * B<maxtries>: Get the number of max tries allowed.  =item * B<duedate>:
   
 =item * B<opendate>: Get the open date for the problem.  Get the due date for the problem.
   
 =item * B<sig>: Get the significant figures setting.  =item * B<tries>:
   
 =item * B<tol>: Get the tolerance for the problem.  Get the number of tries the student has used on the problem.
   
 =item * B<tries>: Get the number of tries the user has already used on the problem.  =item * B<maxtries>:
   
 =item * B<type>: Get the question type for the problem.  Get the number of max tries allowed.
   
 =item * B<weight>: Get the weight for the problem.  =item * B<opendate>:
   
   Get the open date for the problem.
   
   =item * B<sig>:
   
   Get the significant figures setting.
   
   =item * B<tol>:
   
   Get the tolerance for the problem.
   
   =item * B<tries>:
   
   Get the number of tries the user has already used on the problem.
   
   =item * B<type>:
   
   Get the question type for the problem.
   
   =item * B<weight>:
   
   Get the weight for the problem.
   
 =back  =back
   
Line 1955  These methods are responsible for gettin Line 3829  These methods are responsible for gettin
   
 sub acc {  sub acc {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("acc", $part);      my $acc = $self->parmval("acc", $part);
       return $acc;
 }  }
 sub answerdate {  sub answerdate {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     # Handle intervals      # Handle intervals
     if ($self->parmval("answerdate.type", $part) eq 'date_interval') {      my $answerdatetype = $self->parmval("answerdate.type", $part);
         return $self->duedate($part) +       my $answerdate = $self->parmval("answerdate", $part);
             $self->parmval("answerdate", $part);      my $duedate = $self->parmval("duedate", $part);
     }      if ($answerdatetype eq 'date_interval') {
     return $self->parmval("answerdate", $part);          $answerdate = $duedate + $answerdate; 
       }
       return $answerdate;
   }
   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'};
 }  }
   # this should work exactly like the copy in lonhomework.pm
 sub duedate {  sub duedate {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("duedate", $part);      my $date;
       my @interval=$self->parmval("interval", $part);
       my $due_date=$self->parmval("duedate", $part);
       if ($interval[0] =~ /\d+/) {
          my $first_access=&Apache::lonnet::get_first_access($interval[1],
                                                             $self->symb);
    if (defined($first_access)) {
              my $interval = $first_access+$interval[0];
       $date = (!$due_date || $interval < $due_date) ? $interval 
                                                             : $due_date;
    } else {
       $date = $due_date;
    }
       } else {
    $date = $due_date;
       }
       return $date;
   }
   sub handgrade {
       (my $self, my $part) = @_;
       my @response_ids = $self->responseIds($part);
       if (@response_ids) {
    foreach my $response_id (@response_ids) {
               my $handgrade = $self->parmval("handgrade",$part.'_'.$response_id);
       if (lc($handgrade) eq 'yes') {
    return 'yes';
       }
    }
       }
       my $handgrade = $self->parmval("handgrade", $part);
       return $handgrade;
 }  }
 sub maxtries {  sub maxtries {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("maxtries", $part);      my $maxtries = $self->parmval("maxtries", $part);
       return $maxtries;
 }  }
 sub opendate {  sub opendate {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     if ($self->parmval("opendate.type", $part) eq 'date_interval') {      my $opendatetype = $self->parmval("opendate.type", $part);
         return $self->duedate($part) -      my $opendate = $self->parmval("opendate", $part); 
             $self->parmval("opendate", $part);      if ($opendatetype eq 'date_interval') {
           my $duedate = $self->duedate($part);
           $opendate = $duedate - $opendate; 
     }      }
     return $self->parmval("opendate");      return $opendate;
   }
   sub problemstatus {
       (my $self, my $part) = @_;
       my $problemstatus = $self->parmval("problemstatus", $part);
       return lc($problemstatus);
 }  }
 sub sig {  sub sig {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("sig", $part);      my $sig = $self->parmval("sig", $part);
       return $sig;
 }  }
 sub tol {  sub tol {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("tol", $part);      my $tol = $self->parmval("tol", $part);
       return $tol;
 }  }
 sub tries {  sub tries {
     my $self = shift;      my $self = shift; 
     my $part = shift;      my $tries = $self->queryRestoreHash('tries', shift);
     $part = '0' if (!defined($part));      if (!defined($tries)) { return '0';}
   
     # 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;      return $tries;
 }  }
 sub type {  sub type {
     (my $self, my $part) = @_;      (my $self, my $part) = @_;
     return $self->parmval("type", $part);      my $type = $self->parmval("type", $part);
       return $type;
 }  }
 sub weight {  sub weight { 
     (my $self, my $part) = @_;      my $self = shift; my $part = shift;
     return $self->parmval("weight", $part);      if (!defined($part)) { $part = '0'; }
       my $weight = &Apache::lonnet::EXT('resource.'.$part.'.weight',
                                   $self->symb(), $env{'user.domain'},
                                   $env{'user.name'},
                                   $env{'request.course.sec'});
       return $weight;
   }
   sub part_display {
       my $self= shift(); my $partID = shift();
       if (! defined($partID)) { $partID = '0'; }
       my $display=&Apache::lonnet::EXT('resource.'.$partID.'.display',
                                        $self->symb);
       if (! defined($display) || $display eq '') {
           $display = $partID;
       }
       return $display;
 }  }
   
 # Multiple things need this  # Multiple things need this
Line 2043  Misc. functions for the resource. Line 3977  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>:
   
   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<last_post_time>:
   
   Returns a false value if there hasn't been discussion otherwise returns
   unix timestamp of last time a discussion posting (or edit) was made.
   
   =item * B<discussion_info>:
   
   optional argument is a filter (currently can be 'unread');
   returns in scalar context the count of the number of discussion postings.
   
   returns in list context both the count of postings and a hash ref
   containing information about the postings (subject, id, timestamp) in a hash.
   
   Default is to return counts for all postings.  However if called with a second argument set to 'unread', will return information about only unread postings.
   
 =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:  =item * B<getFeedback>:
   
  for (split(/\,/, $res->getFeedback())) {  Gets the feedback for the resource and returns the raw feedback string
     my $link = &Apache::lonnet::escape($_);  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 my $url (split(/\,/, $res->getFeedback())) {
       my $link = &escape($url);
     ...      ...
   
 and use the link as appropriate.  and use the link as appropriate.
Line 2060  sub hasDiscussion { Line 4018  sub hasDiscussion {
     return $self->{NAV_MAP}->hasDiscussion($self->symb());      return $self->{NAV_MAP}->hasDiscussion($self->symb());
 }  }
   
   sub last_post_time {
       my $self = shift;
       return $self->{NAV_MAP}->last_post_time($self->symb());
   }
   
   sub discussion_info {
       my ($self,$filter) = @_;
       return $self->{NAV_MAP}->discussion_info($self->symb(),$filter);
   }
   
 sub getFeedback {  sub getFeedback {
     my $self = shift;      my $self = shift;
     return $self->{NAV_MAP}->getFeedback($self->src());      my $source = $self->src();
       my $symb = $self->symb();
       if ($source =~ /^\/res\//) { $source = substr $source, 5; }
       return $self->{NAV_MAP}->getFeedback($symb,$source);
   }
   
   sub getErrors {
       my $self = shift;
       my $source = $self->src();
       my $symb = $self->symb();
       if ($source =~ /^\/res\//) { $source = substr $source, 5; }
       return $self->{NAV_MAP}->getErrors($symb,$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. Filtering part 0 if you want it is up to you.)  =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<countResponses>():
   
   Returns the total number of responses in the problem a student can answer.
   
   =item * B<responseTypes>():
   
   Returns a hash whose keys are the response types.  The values are the number 
   of times each response type is used.  This is for the I<entire> problem, not 
   just a single part.
   
   =item * B<multipart>():
   
 =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. Thus, B<parts> may return an array with fewer parts in it then countParts might lead you to believe.  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 2078  sub getFeedback { Line 4091  sub getFeedback {
 sub parts {  sub parts {
     my $self = shift;      my $self = shift;
   
     if ($self->ext) { return ['0']; }      if ($self->ext) { return []; }
   
     $self->extractParts();      $self->extractParts();
     return $self->{PARTS};      return $self->{PARTS};
Line 2089  sub countParts { Line 4102  sub countParts {
           
     my $parts = $self->parts();      my $parts = $self->parts();
   
       # If I left this here, then it's not necessary.
       #my $delta = 0;
       #for my $part (@$parts) {
       #    if ($part eq '0') { $delta--; }
       #}
   
     if ($self->{RESOURCE_ERROR}) {      if ($self->{RESOURCE_ERROR}) {
         return 0;          return 0;
     }      }
   
     if (scalar(@{$parts}) < 2) { return 1;}      return scalar(@{$parts}); # + $delta;
   }
   
   sub countResponses {
       my $self = shift;
       my $count;
       foreach my $part (@{$self->parts()}) {
           $count+= scalar($self->responseIds($part));
       }
       return $count;
   }
   
   sub responseTypes {
       my $self = shift;
       my %responses;
       foreach my $part (@{$self->parts()}) {
           foreach my $responsetype ($self->responseType($part)) {
               $responses{$responsetype}++ if (defined($responsetype));
           }
       }
       return %responses;
   }
   
   sub multipart {
       my $self = shift;
       return $self->countParts() > 1;
   }
   
   sub singlepart {
       my $self = shift;
       return $self->countParts() == 1;
   }
   
   sub responseType {
       my $self = shift;
       my $part = shift;
   
       $self->extractParts();
       if (defined($self->{RESPONSE_TYPES}->{$part})) {
    return @{$self->{RESPONSE_TYPES}->{$part}};
       } else {
    return undef;
       }
   }
   
   sub responseIds {
       my $self = shift;
       my $part = shift;
   
     return scalar(@{$parts}) - 1;      $self->extractParts();
       if (defined($self->{RESPONSE_IDS}->{$part})) {
    return @{$self->{RESPONSE_IDS}->{$part}};
       } else {
    return undef;
       }
 }  }
   
 # Private function: Extracts the parts information and saves it  # 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 ($self->ext);      return if ($self->ext);
   
     $self->{PARTS} = [];      $self->{PARTS} = [];
   
       my %parts;
   
     # Retrieve part count, if this is a problem      # Retrieve part count, if this is a problem
     if ($self->is_problem()) {      if ($self->is_problem()) {
         my $metadata = &Apache::lonnet::metadata($self->src(), 'allpossiblekeys');   my $partorder = &Apache::lonnet::metadata($self->src(), 'partorder');
         if (!$metadata) {          my $metadata = &Apache::lonnet::metadata($self->src(), 'packages');
             $self->{RESOURCE_ERROR} = 1;  
             $self->{PARTS} = [];   if ($partorder) {
             return;      my @parts;
       for my $part (split (/,/,$partorder)) {
    if (!Apache::loncommon::check_if_partid_hidden($part, $self->symb())) {
       push @parts, $part;
       $parts{$part} = 1;
    }
       }
       $self->{PARTS} = \@parts;
    } else {
       if (!$metadata) {
    $self->{RESOURCE_ERROR} = 1;
    $self->{PARTS} = [];
    $self->{PART_TYPE} = {};
    return;
       }
       foreach my $entry (split(/\,/,$metadata)) {
    if ($entry =~ /^(?:part|Task)_(.*)$/) {
       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;
         }          }
                   
         foreach (split(/\,/,$metadata)) {  
             if ($_ =~ /^parameter\_(.*)\_opendate$/) {          # These hashes probably do not need names that end with "Hash"....
                 push @{$self->{PARTS}}, $1;          my %responseIdHash;
           my %responseTypeHash;
   
   
           # Init the responseIdHash
           foreach my $part (@{$self->{PARTS}}) {
               $responseIdHash{$part} = [];
           }
   
           # Now, the unfortunate thing about this is that parts, part name, and
           # response id 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 my $data (split /,/, $metadata) {
               if ($data =~ /^([a-zA-Z]+)response_(.*)/
    || $data =~ /^(Task)_(.*)/) {
                   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 $responseId = join('_', @otherChunks);
    if ($self->is_task()) {
       push(@{$responseIdHash{$partIdSoFar}},
    $partIdSoFar);
    } else {
       push(@{$responseIdHash{$partIdSoFar}},
    $responseId);
    }
                           push(@{$responseTypeHash{$partIdSoFar}},
        $responseType);
                       }
                   }
             }              }
         }          }
            my $resorder = &Apache::lonnet::metadata($self->src(),'responseorder');
                   #
         # Is this possible to do in one line? - Jeremy          # Reorder the arrays in the %responseIdHash and %responseTypeHash
         my @sortedParts = sort @{$self->{PARTS}};   if ($resorder) {
         $self->{PARTS} = \@sortedParts;      my @resorder=split(/,/,$resorder);
       foreach my $part (keys(%responseIdHash)) {
    my $i=0;
    my %resids = map { ($_,$i++) } @{ $responseIdHash{$part} };
    my @neworder;
    foreach my $possibleid (@resorder) {
       if (exists($resids{$possibleid})) {
    push(@neworder,$resids{$possibleid});
       }
    }
    my @ids;
    my @type;
    foreach my $element (@neworder) {
       push (@ids,$responseIdHash{$part}->[$element]);
       push (@type,$responseTypeHash{$part}->[$element]);
    }
    $responseIdHash{$part}=\@ids;
    $responseTypeHash{$part}=\@type;
       }
    }
           $self->{RESPONSE_IDS} = \%responseIdHash;
           $self->{RESPONSE_TYPES} = \%responseTypeHash;
     }      }
   
     return;      return;
Line 2135  sub extractParts { Line 4300  sub extractParts {
   
 =head2 Resource Status  =head2 Resource Status
   
 Problem resources have status information, reflecting their various dates and completion statuses.   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 my $part ($resource->parts()) {
     my $dateStatus = $resource->getDateStatus($_);      my $dateStatus = $resource->getDateStatus($part);
     my $completionStatus = $resource->getCompletionStatus($_);      my $completionStatus = $resource->getCompletionStatus($part);
   
     or      or
   
     my $status = $resource->status($_);      my $status = $resource->status($part);
   
     ... 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.  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: $res->OPEN.  The symbolic constants shown below can be accessed through the
   resource object: C<$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. 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 2166  B<Date Codes> Line 4341  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<OPEN>: Open and not yet due.  
   
   =item * B<PAST_DUE_ANSWER_LATER>:
   
 =item * B<PAST_DUE_ANSWER_LATER>: The due date has passed, but the answer date has not yet arrived.  The due date has passed, but the answer date has not yet arrived.
   
 =item * B<PAST_DUE_NO_ANSWER>: The due date has passed and there is no answer opening date set.  =item * B<PAST_DUE_NO_ANSWER>:
   
 =item * B<ANSWER_OPEN>: The answer date is here.  The due date has passed and there is no answer opening date set.
   
 =item * B<NETWORK_FAILURE>: The information is unknown due to network failure.  =item * B<ANSWER_OPEN>:
   
   The answer date is here.
   
   =item * B<NETWORK_FAILURE>:
   
   The information is unknown due to network failure.
   
 =back  =back
   
Line 2231  B<> Line 4418  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):
   
 =back   ($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
   
 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>:
   
 =item * B<INCORRECT>: Attempted, but wrong by student.  Attempted, but wrong by instructor override.
   
 =item * B<INCORRECT_BY_OVERRIDE>: Attempted, but wrong by instructor override.  =item * B<CORRECT>:
   
 =item * B<CORRECT>: Correct or correct by instructor.  Correct or correct by instructor.
   
 =item * B<CORRECT_BY_OVERRIDE>: Correct by instructor override.  =item * B<CORRECT_BY_OVERRIDE>:
   
 =item * B<EXCUSED>: Excused. Not yet implemented.  Correct by instructor override.
   
 =item * B<NETWORK_FAILURE>: Information not available due to network failure.  =item * B<EXCUSED>:
   
 =item * B<ATTEMPTED>: Attempted, and not yet graded.  Excused. Not yet implemented.
   
   =item * B<NETWORK_FAILURE>:
   
   Information not available due to network failure.
   
   =item * B<ATTEMPTED>:
   
   Attempted, and not yet graded.
   
 =back  =back
   
Line 2270  sub ATTEMPTED             { return 16; } Line 4477  sub ATTEMPTED             { return 16; }
 sub getCompletionStatus {  sub getCompletionStatus {
     my $self = shift;      my $self = shift;
     my $part = 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', $part);
     $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 separate 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 $self->CORRECT;}
     if ($status eq 'correct_by_override') {return $self->CORRECT_BY_OVERRIDE; }      if ($status eq 'correct_by_scantron') {return $self->CORRECT;}
       if ($status eq 'correct_by_override') {
    return $self->CORRECT_BY_OVERRIDE;
       }
     if ($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; }
Line 2288  sub getCompletionStatus { Line 4494  sub getCompletionStatus {
     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 * B<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>:
   
 =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 don't know a given part will EVER be opened. For single part, this is the same as "OPEN_LATER".)  The problem is past due, not considered correct, and no answer date is
   set.
   
 =item * B<CORRECT>: For any reason at all, the part is considered correct.  =item * B<PAST_DUE_ANSWER_LATER>:
   
 =item * B<EXCUSED>: For any reason at all, the problem is excused.  The problem is past due, not considered correct, and an answer date in
   the future is set.
   
 =item * B<PAST_DUE_NO_ANSWER>: The problem is past due, not considered correct, and no answer date is set.  =item * B<ANSWER_OPEN>:
   
 =item * B<PAST_DUE_ANSWER_LATER>: The problem is past due, not considered correct, and an answer date in the future is set.  The problem is past due, not correct, and the answer is now available.
   
 =item * B<ANSWER_OPEN>: The problem is past due, not correct, and the answer is now available.  =item * B<OPEN_LATER>:
   
 =item * B<OPEN_LATER>: The problem is not yet open.  The problem is not yet open.
   
 =item * B<TRIES_LEFT>: The problem is open, has been tried, is not correct, but there are tries left.  =item * B<TRIES_LEFT>:
   
 =item * B<INCORRECT>: The problem is open, and all tries have been used without getting the correct answer.  The problem is open, has been tried, is not correct, but there are
   tries left.
   
 =item * B<OPEN>: The item is open and not yet tried.  =item * B<INCORRECT>:
   
 =item * B<ATTEMPTED>: The problem has been attempted.  The problem is open, and all tries have been used without getting the
   correct answer.
   
   =item * B<OPEN>:
   
   The item is open and not yet tried.
   
   =item * B<ATTEMPTED>:
   
   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 PARTIALLY_CORRECT{ return 22; }
   
 sub status {  sub status {
     my $self = shift;      my $self = shift;
Line 2337  sub status { Line 4603  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 $suppressFeedback = 0;
       if (($self->problemstatus($part) eq 'no') ||
           ($self->problemstatus($part) eq 'no_feedback_ever')) {
           $suppressFeedback = 1;
       }
       # If there's an answer date and we're past it, don't
       # suppress the feedback; student should know
       if ($self->duedate($part) && $self->duedate($part) < time() &&
    $self->answerdate($part) && $self->answerdate($part) < time()) {
    $suppressFeedback = 0;
       }
   
     # 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;    if ( $suppressFeedback ) { return ANSWER_SUBMITTED }
    my $awarded=$self->awarded($part);
    if ($awarded < 1 && $awarded > 0) {
               return PARTIALLY_CORRECT;
    } elsif ($awarded<1) {
       return INCORRECT;
    }
    return CORRECT; 
       }
   
       # If it's WRONG... and not open
       if ( ($completionStatus == INCORRECT || 
     $completionStatus == INCORRECT_BY_OVERRIDE)
    && (!$self->opendate($part) ||  $self->opendate($part) > time()) ) {
    return INCORRECT;
     }      }
   
     if ($completionStatus == ATTEMPTED) {      if ($completionStatus == ATTEMPTED) {
Line 2363  sub status { Line 4656  sub status {
   
     if ($dateStatus == PAST_DUE_ANSWER_LATER ||      if ($dateStatus == PAST_DUE_ANSWER_LATER ||
         $dateStatus == PAST_DUE_NO_ANSWER ) {          $dateStatus == PAST_DUE_NO_ANSWER ) {
         return $dateStatus;           return $suppressFeedback ? ANSWER_SUBMITTED : $dateStatus; 
     }      }
   
     if ($dateStatus == ANSWER_OPEN) {      if ($dateStatus == ANSWER_OPEN) {
Line 2381  sub status { Line 4674  sub status {
     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($part) < $self->maxtries($part) || !$self->maxtries($part)) {          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
     return OPEN;       return OPEN; 
 }  }
   
   sub CLOSED { return 23; }
   sub ERROR { return 24; }
   
   =pod
   
   B<Simple Status>
   
   Convenience method B<simpleStatus> provides a "simple status" for the resource.
   "Simple status" corresponds to "which icon is shown on the
   Navmaps". There are six "simple" statuses:
   
   =over 4
   
   =item * B<CLOSED>: The problem is currently closed. (No icon shown.)
   
   =item * B<OPEN>: The problem is open and unattempted.
   
   =item * B<CORRECT>: The problem is correct for any reason.
   
   =item * B<INCORRECT>: The problem is incorrect and can still be
   completed successfully.
   
   =item * B<ATTEMPTED>: The problem has been attempted, but the student
   does not know if they are correct. (The ellipsis icon.)
   
   =item * B<ERROR>: There is an error retrieving information about this
   problem.
   
   =back
   
   =cut
   
   # This hash maps the composite status to this simple status, and
   # can be used directly, if you like
   my %compositeToSimple = 
       (
         NETWORK_FAILURE()       => ERROR,
         NOTHING_SET()           => CLOSED,
         CORRECT()               => CORRECT,
         PARTIALLY_CORRECT()     => PARTIALLY_CORRECT,
         EXCUSED()               => CORRECT,
         PAST_DUE_NO_ANSWER()    => INCORRECT,
         PAST_DUE_ANSWER_LATER() => INCORRECT,
         ANSWER_OPEN()           => INCORRECT,
         OPEN_LATER()            => CLOSED,
         TRIES_LEFT()            => OPEN,
         INCORRECT()             => INCORRECT,
         OPEN()                  => OPEN,
         ATTEMPTED()             => ATTEMPTED,
         ANSWER_SUBMITTED()      => ATTEMPTED
        );
   
   sub simpleStatus {
       my $self = shift;
       my $part = shift;
       my $status = $self->status($part);
       return $compositeToSimple{$status};
   }
   
   =pod
   
   B<simpleStatusCount> will return an array reference containing, in
   this order, the number of OPEN, CLOSED, CORRECT, INCORRECT, ATTEMPTED,
   and ERROR parts the given problem has.
   
   =cut
       
   # This maps the status to the slot we want to increment
   my %statusToSlotMap = 
       (
        OPEN()      => 0,
        CLOSED()    => 1,
        CORRECT()   => 2,
        INCORRECT() => 3,
        ATTEMPTED() => 4,
        ERROR()     => 5
        );
   
   sub statusToSlot { return $statusToSlotMap{shift()}; }
   
   sub simpleStatusCount {
       my $self = shift;
   
       my @counts = (0, 0, 0, 0, 0, 0, 0);
       foreach my $part (@{$self->parts()}) {
    $counts[$statusToSlotMap{$self->simpleStatus($part)}]++;
       }
   
       return \@counts;
   }
   
   =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  =pod
   
 =head2 Resource/Nav Map Navigation  =head2 Resource/Nav Map Navigation
   
 =over 4  =over 4
   
 =item * B<getNext>(): 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<getNext>():
   
   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>(): Retreive an array of the possible previous resources from this one. Always returns an array, even in the one- or zero-element case.   =item * B<getPrevious>():
   
   Retreive an array of the possible previous resources from this
   one. Always returns an array, even in the one- or zero-element case.
   
 =cut  =cut
   
Line 2408  sub getNext { Line 4843  sub getNext {
     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);
           #if (!$choice->condition()) { next; }
         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 the student doesn't have browse priviledges          push @branches, $next;
         # future note: this may properly belong in the client of the resource  
         my $browsePriv = &Apache::lonnet::allowed('bre', $self->src);  
         if ($browsePriv ne '2' && $browsePriv ne 'F') {  
             push @branches, $next;  
         }  
     }      }
     return \@branches;      return \@branches;
 }  }
Line 2430  sub getPrevious { Line 4861  sub getPrevious {
         my $prev = $choice->comesfrom();          my $prev = $choice->comesfrom();
         $prev = $self->{NAV_MAP}->getById($prev);          $prev = $self->{NAV_MAP}->getById($prev);
   
         # Don't remember it if the student doesn't have browse priviledges          push @branches, $prev;
         # future note: this may properly belong in the client of the resource  
         my $browsePriv = &Apache::lonnet::allowed('bre', $self->src);  
         if ($browsePriv ne '2' && $browsePriv ne 'F') {  
             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(),
       $self->symb());
   }
   
 =pod  =pod
   
 =back  =back

Removed from v.1.101  
changed lines
  Added in v.1.415.4.1


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