--- loncom/interface/lonnavmaps.pm 2002/10/01 07:09:05 1.57 +++ loncom/interface/lonnavmaps.pm 2002/10/24 19:10:07 1.86 @@ -1,7 +1,8 @@ + # The LearningOnline Network with CAPA # Navigate Maps Handler # -# $Id: lonnavmaps.pm,v 1.57 2002/10/01 07:09:05 albertel Exp $ +# $Id: lonnavmaps.pm,v 1.86 2002/10/24 19:10:07 bowersj2 Exp $ # # Copyright Michigan State University Board of Trustees # @@ -44,8 +45,8 @@ use strict; use Apache::Constants qw(:common :http); use Apache::lonnet(); use Apache::loncommon(); -use HTML::TokeParser; use GDBM_File; +use POSIX qw (floor strftime); # -------------------------------------------------------------- Module Globals my %hash; @@ -819,13 +820,10 @@ sub new_handle { &Apache::loncommon::no_cache($r); $r->send_http_header; - # Header - $r->print(&Apache::loncommon::bodytag('Navigate Course Map','', - '')); # Initialize the nav map my $navmap = Apache::lonnavmaps::navmap->new( $ENV{"request.course.fn"}.".db", - $ENV{"request.course.fn"}."_parms.db", 1); + $ENV{"request.course.fn"}."_parms.db", 1, 1); if (!defined($navmap)) { @@ -834,6 +832,24 @@ sub new_handle { return HTTP_NOT_ACCEPTABLE; } + # Header + $r->print(&Apache::loncommon::bodytag('Navigate Course Map','', + '')); + $r->print(''); + my $desc=$ENV{'course.'.$ENV{'request.course.id'}.'.description'}; + if (defined($desc)) { $r->print("

$desc

\n"); } + my $date=localtime; + $r->print("

$date

\n"); + $r->rflush(); + if ($navmap->{LAST_CHECK}) { + $r->print(' New discussion since '. + strftime("%A, %b %e at %I:%M %P", localtime($navmap->{LAST_CHECK})). + '
New message (click to open)

'); + } else { + $r->print(' Discussions'. + '
New message (click to open)

'); + } + # Check that it's defined if (!($navmap->courseMapDefined())) { $r->print('Coursemap undefined.' . @@ -848,16 +864,43 @@ sub new_handle { # Defines a status->color mapping, null string means don't color my %colormap = ( $res->NETWORK_FAILURE => '', - $res->CORRECT => '#BBFFBB', + $res->CORRECT => '', $res->EXCUSED => '#BBBBFF', - $res->PAST_DUE_ANSWER_LATER => '#FFAA00', - $res->PAST_DUE_NO_ANSWER => '#FFAA00', - $res->ANSWER_OPEN => '#FF00AA', + $res->PAST_DUE_ANSWER_LATER => '', + $res->PAST_DUE_NO_ANSWER => '', + $res->ANSWER_OPEN => '#CCFFCC', $res->OPEN_LATER => '', - $res->TRIES_LEFT => '#FFFF00', - $res->INCORRECT => '#FFAA00', - $res->OPEN => '#FFFF88', + $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 @@ -867,19 +910,79 @@ sub new_handle { } } + 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"; + + $r->print('Show All Resources

'); + # Begin the HTML table - # two columns: the title/icon on the left, the info on the right - $r->print('' ."\n"); + # four cols: resource + indent, chat+feedback, icon, text string + $r->print('
' ."\n"); + + my $condition = 0; + if ($ENV{'form.condition'}) { + $condition = 1; + } + + # This needs to be updated to use symbs from the remote, + # instead of uris. The changes to this and the main rendering + # loop should be obvious. + # Here's a simple example of the iterator. + # If there is a current resource + if ($currenturl && !$ENV{'form.alreadyHere'}) { + # Give me every resource... + my $mapIterator = $navmap->getIterator(undef, undef, {}, 1); + my $found = 0; + my $depth = 1; + $mapIterator->next(); # discard the first BEGIN_MAP + my $curRes = $mapIterator->next(); + + while ($depth > 0 && !$found) { + if (ref($curRes) && $curRes->src() eq $currenturl) { + # If this is the correct resource, be sure to + # show it by making sure the containing maps + # are open. + + my $mapStack = $mapIterator->getStack(); + for my $map (@{$mapStack}) { + if ($condition) { + undef $filterHash{$map->map_pc()}; + } else { + $filterHash{$map->map_pc()} = 1; + } + } + $found = 1; + } + $curRes = $mapIterator->next(); + } + } - my $mapIterator = $navmap->getIterator(undef, undef, \%filterHash); - my $curRes = $mapIterator->next(); undef $res; # so we don't accidentally use it later - my $indentLevel = -1; - my $indentString = "        "; + my $indentLevel = 0; + my $indentString = "\"\""; my $isNewBranch = 0; + my $now = time(); + my $in24Hours = $now + 24 * 60 * 60; + my $depth = 1; + my $displayedHereMarker = 0; + + # We know the first thing is a BEGIN_MAP (see "$self->{STARTED}" + # code in iterator->next), so ignore the first one + my $mapIterator = $navmap->getIterator(undef, undef, \%filterHash, + $condition); + $mapIterator->next(); + my $curRes = $mapIterator->next(); - while ($curRes != $mapIterator->END_NAV_MAP) { + while ($depth > 0) { if ($curRes == $mapIterator->BEGIN_MAP() || $curRes == $mapIterator->BEGIN_BRANCH()) { $indentLevel++; @@ -891,20 +994,107 @@ sub new_handle { if ($curRes == $mapIterator->BEGIN_BRANCH()) { $isNewBranch = 1; } + if ($curRes == $mapIterator->BEGIN_MAP()) { + $depth++; + } + if ($curRes == $mapIterator->END_MAP()) { + $depth--; + } + + # Is this resource being blotted out? + if (ref($curRes) && !advancedUser() && $curRes->randomout()) { + $curRes = $mapIterator->next(); + next; # and totally ignore this resource + } if (ref($curRes) && $curRes->src()) { - my @parts; + # Step one: Decide which parts to show + my @parts = @{$curRes->parts()}; + my $multipart = scalar(@parts) > 1; + my $condensed = 0; + if ($curRes->is_problem()) { - @parts = @{$curRes->parts()}; - if (scalar(@parts) > 1) { shift(@parts); } + # Is it multipart? + + if ($multipart) { + # If it's multipart, see if part 0 is "open" + # if it is, display all parts, if it isn't, + # just display first + if (!$curRes->opendate("0")) { + @parts = ("0"); # just display the zero-th part + $condensed = 1; + } else { + # Otherwise, only display part 0 if we want to + # attach feedback or email information to it + if ($curRes->hasDiscussion() || $curRes->getFeedback()) { + shift @parts; + } else { + # If there's discussion or feedback, that counts + # as a difference, so display the parts. + + # Now, we decide whether to condense the + # parts due to similarity + my $status = $curRes->status($parts[1]); + my $due = $curRes->duedate($parts[1]); + my $open = $curRes->opendate($parts[1]); + my $statusAllSame = 1; + my $dueAllSame = 1; + my $openAllSame = 1; + for (my $i = 2; $i < scalar(@parts); $i++) { + if ($curRes->status($parts[$i]) != $status){ + $statusAllSame = 0; + } + if ($curRes->duedate($parts[$i]) != $due ) { + $dueAllSame = 0; + } + if ($curRes->opendate($parts[$i]) != $open) { + $openAllSame = 0; + } + } + + # $allSame is true if all the statuses were + # the same. Now, if they are all the same and + # match one of the statuses to condense, or they + # are all open with the same due date, or they are + # all OPEN_LATER with the same open date, display the + # status of the first non-zero part (to get the 'correct' + # status right, since 0 is never 'correct' or 'open'). + if (($statusAllSame && defined($condenseStatuses{$status})) || + ($dueAllSame && $status == $curRes->OPEN && $statusAllSame)|| + ($openAllSame && $status == $curRes->OPEN_LATER && $statusAllSame) ){ + @parts = ($parts[1]); + $condensed = 1; + } + } + } + } + } else { - @parts[0] = "0"; # this is to get past foreach loop below + $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 + # with only one part without loss + } + + # 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 ) { + $multipart = 0; + } + + # Display one part, in event of network error. + # If this is a single part, we can at least show the correct + # status, but if it's multipart, we're lost. + if ($curRes->{RESOURCE_ERROR}) { + @parts = ("0"); } + # Step two: Show the parts foreach my $part (@parts) { + + my $deltalevel = 0; # for inserting the branch icon + my $nonLinkedText = ""; # unlinked stuff after title # For each thing we're displaying... @@ -917,68 +1107,176 @@ sub new_handle { 'symb='.&Apache::lonnet::escape($curRes->symb()). '"'; my $title = $curRes->title(); + if (!$title) { + $title = $curRes->src(); + $title = substr ($title, rindex($title, "/") + 1); + } my $partLabel = ""; my $newBranchText = ""; # If this is a new branch, label it so # (temporary, this should be an icon w/ alt text) if ($isNewBranch) { - $newBranchText = "NB -> "; + $newBranchText = ""; $isNewBranch = 0; + $deltalevel = 1; } # links to open and close the folders my $linkopen = ""; my $linkclose = ""; - my $icon = "html.gif"; + my $icon = "\"\""; if ($curRes->is_problem()) { - $icon = "problem.gif"; + if ($part eq "0" || $condensed) { + $icon = ''; + } 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}); + my $nowOpen = (!defined($filterHash{$mapId})); + if ($condition) {$nowOpen = !$nowOpen;} $icon = $nowOpen ? - "folder_opened.gif" : "folder_closed.gif"; + "navmap.folder.closed.gif" : "navmap.folder.open.gif"; + $icon = "\"\""; $linkopen = ""; + $linkopen .= "&condition=$condition&$queryAdd\">"; $linkclose = ""; - + } my $colorizer = ""; + my $color; if ($curRes->is_problem()) { my $status = $curRes->status($part); - my $color = $colormap{$status}; + $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, give a bit of urgency + my $tries = $curRes->tries($part); + my $maxtries = $curRes->maxtries($part); + if ($tries && $maxtries && $maxtries > 1 && + $maxtries - $tries == 1) { + $color = $hurryUpColor; + } if ($color ne "") { $colorizer = "bgcolor=\"$color\""; } } - $r->print(" ". - ""); + + # Is this the first displayed part of a multi-part problem + # that has not been condensed, so we should suppress these two + # columns? + 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("\n"); + } else { + $r->print("\n"); + } + } else { # not problem, no icon + $r->print("\n"); + } + + # FOURTH COL: Text description + #$r->print("\n"); } } $curRes = $mapIterator->next(); @@ -986,6 +1284,8 @@ sub new_handle { $r->print("
\n"); + if ($curRes->randomout()) { + $nonLinkedText .= ' (hidden) '; + } + + # FIRST COL: The resource indentation, branch icon, and name + $r->print("
\n"); # print indentation - for (my $i = 0; $i < $indentLevel; $i++) { + for (my $i = 0; $i < $indentLevel - $deltalevel; $i++) { $r->print($indentString); } - $r->print(" ${newBranchText}${linkopen}\"\"${linkclose}\n"); + $r->print(" ${newBranchText}${linkopen}$icon${linkclose}\n"); - if ($curRes->is_problem() && $part != "0") { $partLabel = " (Part $part)"; } + my $curMarkerBegin = ""; + my $curMarkerEnd = ""; - $r->print(" $title$partLabel\n"); + # Is this the current resource? + if ($curRes->src() eq $currenturl && !$displayedHereMarker) { + $curMarkerBegin = '> '; + $curMarkerEnd = ' <'; + $displayedHereMarker = 1; + } + + if ($curRes->is_problem() && $part ne "0" && !$condensed) { + $partLabel = " (Part $part)"; + $title = ""; + } + if ($multipart && $condensed) { + $nonLinkedText .= ' (' . $curRes->countParts() . ' parts)'; + } + + $r->print(" $curMarkerBegin$title$partLabel $curMarkerEnd $nonLinkedText"); + + if ($curRes->{RESOURCE_ERROR}) { + $r->print(&Apache::loncommon::help_open_topic ("Navmap_Host_Down", + 'Host down')); + } + + my $discussionHTML = ""; my $feedbackHTML = ""; + + # SECOND COL: Is there text, feedback, errors?? + if ($curRes->hasDiscussion()) { + $discussionHTML = $linkopen . + '' . + $linkclose; + } + + if ($curRes->getFeedback()) { + my $feedback = $curRes->getFeedback(); + foreach (split(/\,/, $feedback)) { + if ($_) { + $feedbackHTML .= ' ' + . ''; + } + } + } + + $r->print("$discussionHTML$feedbackHTML $linkopen\"$alt\"$linkclose  \n"); + $r->print("\n"); - if ($curRes->kind() eq "res" and - $curRes->is_problem() ) { + if ($curRes->kind() eq "res" && + $curRes->is_problem() && + !$firstDisplayed) { + $r->print ("") if ($color); $r->print (getDescription($curRes, $part)); + $r->print ("") if ($color); + } + if ($curRes->is_map() && advancedUser() && $curRes->randompick()) { + $r->print('(randomly select ' . $curRes->randompick() .')'); } + + $r->print(" 
"); + $navmap->untieHashes(); + return OK; } @@ -1044,44 +1344,169 @@ sub getLinkForResource { sub getDescription { my $res = shift; my $part = shift; - my $status = $res->getDateStatus(); + my $status = $res->status($part); if ($status == $res->NETWORK_FAILURE) { return ""; } if ($status == $res->NOTHING_SET) { return "Not currently assigned."; } if ($status == $res->OPEN_LATER) { - return "Opens: " . timeToHumanString($res->opendate($part)); + return "Open " . timeToHumanString($res->opendate($part)); } if ($status == $res->OPEN) { - return "Due: $status " . timeToHumanString($res->duedate($part)); + if ($res->duedate($part)) { + return "Due " . timeToHumanString($res->duedate($part)); + } else { + return "Open, no due date"; + } } if ($status == $res->PAST_DUE_ANSWER_LATER) { - return "Answer: " . timeToHumanString($res->answerdate($part)); + return "Answer open " . timeToHumanString($res->answerdate($part)); } if ($status == $res->PAST_DUE_NO_ANSWER) { - return "Was Due: " . timeToHumanString($res->duedate($part)); + return "Was due " . timeToHumanString($res->duedate($part)); } if ($status == $res->ANSWER_OPEN) { return "Answer available"; } + if ($status == $res->EXCUSED) { + return "Excused by instructor"; + } + if ($status == $res->ATTEMPTED) { + return "Not yet graded."; + } + if ($status == $res->TRIES_LEFT) { + my $tries = $res->tries($part); + my $maxtries = $res->maxtries($part); + my $triesString = ""; + if ($tries && $maxtries) { + $triesString = "($tries of $maxtries tries used)"; + if ($maxtries > 1 && $maxtries - $tries == 1) { + $triesString = "$triesString"; + } + } + if ($res->duedate()) { + return "Due " . timeToHumanString($res->duedate($part)) . + " $triesString"; + } else { + return "No due date $triesString"; + } + } } -# I want to change this into something more human-friendly. For -# now, this is a simple call to localtime. The final function -# probably belongs in loncommon. +sub advancedUser { + return $ENV{'user.adv'}; +} + + +# timeToHumanString takes a time number and converts it to a +# human-readable representation, meant to be used in the following +# manner: +# print "Due $timestring" +# print "Open $timestring" +# print "Answer available $timestring" +# Very, very, very, VERY English-only... goodness help a localizer on +# this func... sub timeToHumanString { - return localtime(shift); + my ($time) = @_; + # zero, '0' and blank are bad times + if (!$time) { + return 'never'; + } + + my $now = time(); + + my @time = localtime($time); + my @now = localtime($now); + + # Positive = future + my $delta = $time - $now; + + my $minute = 60; + my $hour = 60 * $minute; + my $day = 24 * $hour; + my $week = 7 * $day; + my $inPast = 0; + + # Logic in comments: + # Is it now? (extremely unlikely) + if ( $delta == 0 ) { + return "this instant"; + } + + if ($delta < 0) { + $inPast = 1; + $delta = -$delta; + } + + # Is it in the future? + if ( $delta > 0 ) { + # Is it less then a minute away? + my $tense = $inPast ? " ago" : ""; + my $prefix = $inPast ? "" : "in "; + if ( $delta < $minute ) { + if ($delta == 1) { return "${prefix}1 second$tense"; } + return "$prefix$delta seconds$tense"; + } + + # Is it less then an hour away? + if ( $delta < $hour ) { + # If so, use minutes + my $minutes = floor($delta / 60); + if ($minutes == 1) { return "${prefix}1 minute$tense"; } + return "$prefix$minutes minutes$tense"; + } + + # Is it less then 24 hours away? If so, + # display hours + minutes + if ( $delta < $hour * 24) { + my $hours = floor($delta / $hour); + my $minutes = floor(($delta % $hour) / $minute); + my $hourString = "$hours hours"; + my $minuteString = ", $minutes minutes"; + if ($hours == 1) { + $hourString = "1 hour"; + } + if ($minutes == 1) { + $minuteString = ", 1 minute"; + } + if ($minutes == 0) { + $minuteString = ""; + } + return "$prefix$hourString$minuteString$tense"; + } + + # Less then 5 days away, display day of the week and + # HH:MM + if ( $delta < $day * 5 ) { + my $timeStr = strftime("%A, %b %e at %I:%M %P", localtime($time)); + $timeStr =~ s/12:00 am/midnight/; + $timeStr =~ s/12:00 pm/noon/; + return ($inPast ? "last " : "next ") . + $timeStr; + } + + # Is it this year? + if ( $time[5] == $now[5]) { + # Return on Month Day, HH:MM meridian + my $timeStr = strftime("on %A, %b %e at %I:%M %P", localtime($time)); + $timeStr =~ s/12:00 am/midnight/; + $timeStr =~ s/12:00 pm/noon/; + return $timeStr; + } + + # Not this year, so show the year + my $timeStr = strftime("on %A, %b %e %G at %I:%M %P", localtime($time)); + $timeStr =~ s/12:00 am/midnight/; + $timeStr =~ s/12:00 pm/noon/; + return $timeStr; + } } 1; package Apache::lonnavmaps::navmap; -# LEFT: -# * Actual handler code (multi-part) -# * Branches (aieee!) (and conditionals) - =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. @@ -1098,7 +1523,7 @@ You must obtain resource objects through =over 4 -=item * B(filename, parmHashFile, genCourseAndUserOptions, genMailDiscussStatus): Binds a new navmap object to the compiled course representation and parmHashFile. genCourseAndUserOptions is a flag saying whether the course options and user options hash should be generated. This is for when you are using the parameters of the resources that require them; see documentation in resource object documentation. genMailDiscussStatus causes the nav map to retreive information about the email and discussion status of resources. Returns the navmap object if this is successful, or B if not. You must check for undef; errors will occur when you try to use the other methods otherwise. +=item * B(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 if not. You must check for undef; errors will occur when you try to use the other methods otherwise. =item * B(first, finish, filter, condition): See iterator documentation below. @@ -1138,6 +1563,7 @@ sub new { if (!(tie(%parmhash, 'GDBM_File', $self->{PARM_HASH_FILE}, &GDBM_READER(), 0640))) { + untie $self->{PARM_HASH}; return undef; } $self->{PARM_HASH} = \%parmhash; @@ -1245,6 +1671,8 @@ sub new { $self->{EMAIL_STATUS} = \%emailstatus; } + + $self->{PARM_CACHE} = {}; bless($self); @@ -1264,15 +1692,15 @@ sub courseMapDefined { sub getIterator { my $self = shift; my $iterator = Apache::lonnavmaps::iterator->new($self, shift, shift, - shift, shift); + shift, undef, shift); return $iterator; } # unties the hash when done sub untieHashes { my $self = shift; - untie $self->{NAV_HASH} if ($self->{HASH_TIED}); - untie $self->{PARM_HASH} if ($self->{HASH_TIED}); + untie %{$self->{NAV_HASH}} if ($self->{HASH_TIED}); + untie %{$self->{PARM_HASH}} if ($self->{HASH_TIED}); $self->{HASH_TIED} = 0; } @@ -1282,6 +1710,29 @@ sub DESTROY { $self->untieHashes(); } +# Private function: Does the given resource (as a symb string) have +# current discussion? Returns 0 if chat/mail data not extracted. +sub hasDiscussion { + my $self = shift; + my $symb = shift; + if (!defined($self->{DISCUSSION_TIME})) { return 0; } + + return $self->{DISCUSSION_TIME}->{$symb} > + $self->{LAST_CHECK}; +} + +# Private function: Does the given resource (as a symb string) have +# current feedback? Returns the string in the feedback hash, which +# will be false if it does not exist. +sub getFeedback { + my $self = shift; + my $symb = shift; + + if (!defined($self->{FEEDBACK})) { return ""; } + + return $self->{FEEDBACK}->{$symb}; +} + =pod =item * B(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. @@ -1343,6 +1794,21 @@ sub finishResource { sub parmval { my $self = shift; my ($what,$symb)=@_; + my $hashkey = $what."|||".$symb; + + if (defined($self->{PARM_CACHE}->{$hashkey})) { + return $self->{PARM_CACHE}->{$hashkey}; + } + + my $result = $self->parmval_real($what, $symb); + $self->{PARM_CACHE}->{$hashkey} = $result; + return $result; +} + +sub parmval_real { + my $self = shift; + my ($what,$symb) = @_; + my $cid=$ENV{'request.course.id'}; my $csec=$ENV{'request.course.sec'}; my $uname=$ENV{'user.name'}; @@ -1450,25 +1916,32 @@ getIterator behaves as follows: =over 4 -=item B(nav_map, firstResource, finishResource, filterHash): All parameters are optional. firstResource is a resource reference corresponding to where the iterator should start. It defaults to navmap->firstResource() for the corresponding nav map. finishResource corresponds to where you want the iterator to end, defaulting to navmap->finishResource(). It is your responsibility to ensure that the iterator will actually get there. filterHash is a hash used as a set containing strings representing the resource IDs, defaulting to empty. Condition is a 1 or 0 that sets what to do with the filter hash: If a 1, then only resource that exist IN the filterHash will be recursed on. If it is a 0, only resources NOT in the filterHash will be recursed on. Defaults to 0. +=item B(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, which is to say, do not recurse unless explicitly asked to. -Thus, by default, all resources will be shown. Change the condition to a 1 without changing the hash, and only the top level of the map will be shown. Changing the condition to 1 and including some values in the hash will allow you to selectively examine parts of the navmap, while leaving it on 0 and adding things to the hash will allow you to selectively ignore parts of the nav map. See the handler code for examples. +Thus, by default, all resources will be shown. Change the condition to a 1 without changing the hash, and only the top level of the map will be shown. Changing the condition to 1 and including some values in the hash will allow you to selectively examine parts of the navmap, while leaving it on 0 and adding things to the hash will allow you to selectively ignore parts of the nav map. See the handler code for examples: By default, the condition is 0 and all folders are closed unless explicitly opened. Clicking "Show All Resources" will use a condition of 1 and an empty filterHash, resulting in all resources being shown. 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 -=item * some list of tokens here +=item * BEGIN_MAP: A new map is being recursed into. This is returned I the map resource itself is returned. + +=item * END_MAP: The map is now done. + +=item * BEGIN_BRANCH: A branch is now starting. The next resource returned will be the first in that branch. + +=item * END_BRANCH: The branch is now done. =back -The tokens are retreivable via methods on the iterator object, i.e., $iterator->END_NAV_MAP. (Perl will automatically optimize these into constants. +The tokens are retreivable via methods on the iterator object, i.e., $iterator->END_MAP. + +=back =cut # Here are the tokens for the iterator: -sub END_NAV_MAP { return 0; } # Represents end of entire nav map sub BEGIN_MAP { return 1; } # begining of a new map sub END_MAP { return 2; } # end of the map sub BEGIN_BRANCH { return 3; } # beginning of a branch @@ -1502,6 +1975,7 @@ sub new { # A hash, used as a set, of resource already seen $self->{ALREADY_SEEN} = shift; if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} }; + $self->{CONDITION} = shift; # Flag: Have we started yet? If not, the first action is to return BEGIN_MAP. $self->{STARTED} = 0; @@ -1541,13 +2015,6 @@ sub next { # Iterator logic goes here - # Is this return value pre-determined? - if (defined($self->{FORCE_NEXT})) { - my $tmp = $self->{FORCE_NEXT}; - $self->{FORCE_NEXT} = undef; - return $tmp; - } - # Are we using a recursive iterator? If so, pull from that and # watch the depth; we want to resume our level at the correct time. if ($self->{RECURSIVE_ITERATOR_FLAG}) @@ -1567,6 +2034,13 @@ sub next { return $next; } + # Is this return value pre-determined? + if (defined($self->{FORCE_NEXT})) { + my $tmp = $self->{FORCE_NEXT}; + $self->{FORCE_NEXT} = undef; + return $tmp; + } + # Is there a current resource to grab? If not, then return # END_BRANCH and END_MAP in succession. if (scalar(@{$self->{BRANCH_STACK}}) == 0) { @@ -1622,12 +2096,6 @@ sub next { # remember that we've seen this. $self->{ALREADY_SEEN}->{$self->{HERE}->{ID}} = 1; - # Are we at the utter end? If so, return the END_NAV_MAP marker. - if ($self->{HERE} == $self->{NAV_MAP}->finishResource() ) { - $self->{FORCE_NEXT} = $self->END_NAV_MAP; - return $self->{HERE}; - } - # Get the next possible resources my $nextUnfiltered = $self->{HERE}->getNext(); my $next = []; @@ -1655,7 +2123,6 @@ sub next { $self->{FORCE_NEXT} = $self->END_BRANCH(); $self->{BRANCH_DEPTH}--; } - return $self->{HERE}; } while (@$next) { @@ -1672,19 +2139,15 @@ sub next { # If this is a map and we want to recurse down it... (not filtered out) if ($self->{HERE}->is_map() && - !defined($self->{FILTER}->{$self->{HERE}->map_pc()})) { + (defined($self->{FILTER}->{$self->{HERE}->map_pc()}) xor $self->{CONDITION})) { $self->{RECURSIVE_ITERATOR_FLAG} = 1; my $firstResource = $self->{HERE}->map_start(); my $finishResource = $self->{HERE}->map_finish(); - # Odd perl syntax here; $self->new allows one to create a new iterator - # can't figure out how to ref this package directly correctly - # isn't MAIN::new, __PACKAGE__::new or Apache::lonnavmaps::iterator->new $self->{RECURSIVE_ITERATOR} = Apache::lonnavmaps::iterator->new ($self->{NAV_MAP}, $firstResource, - $finishResource, $self->{FILTER}, $self->{ALREADY_SEEN}); - # prime the new iterator with the first resource - #push @{$self->{RECURSIVE_ITERATOR}->{BRANCH_STACK}}, $firstResource; + $finishResource, $self->{FILTER}, $self->{ALREADY_SEEN}, + $self->{CONDITION}); } return $self->{HERE}; @@ -1742,7 +2205,9 @@ resource objects have a hash called DATA =over 4 -=item * B($navmapRef, $idString): The first arg is a reference to the parent navmap object. The second is the idString of the resource itself. +=item * B($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. + +=back =cut @@ -1757,6 +2222,7 @@ sub new { # Store this new resource in the parent nav map's cache. $self->{NAV_MAP}->{RESOURCE_CACHE}->{$self->{ID}} = $self; + $self->{RESOURCE_ERROR} = 0; # A hash that can be used by two-pass algorithms to store data # about this resource in. Not used by the resource object @@ -1768,20 +2234,6 @@ sub new { return $self; } -=pod - -=item * B: Returns true if this is a map, false otherwise. - -=item * B: Returns title. - -=item * B<type>: Returns the type of the resource, "start", "normal", or "finish". - -=item * B<problem>: Returns true if the resource is a problem type, false otherwise. (Looks at the extension on the src field.) - -=back - -=cut - # private function: simplify the NAV_HASH lookups we keep doing # pass the name, and to automatically append my ID, pass a true val on the # second param @@ -1792,14 +2244,49 @@ sub navHash { return $self->{NAV_MAP}->{NAV_HASH}->{$param . ($id?$self->{ID}:"")}; } +=pod + +B<Metadata Retreival> + +These are methods that help you retrieve metadata about the resource: + +=over 4 + +=item * B<ext>: Returns true if the resource is external. + +=item * B<goesto>: Returns the "goesto" value from the compiled nav map. (It is likely you want to use B<getNext> instead.) + +=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. + +=item * B<randompick>: Returns true for a map if the randompick feature is being used on the map. (?) + +=item * B<src>: Returns the source for the resource. + +=item * B<symb>: Returns the symb for the resource. + +=item * B<title>: Returns the title of the resource. + +=item * B<to>: Returns the "to" value from the compiled nav map. (It is likely you want to use B<getNext> instead.) + +=back + +=cut + # These info functions can be used directly, as they don't return # resource information. -sub title { my $self=shift; return $self->navHash("title_", 1); } -sub type { my $self=shift; return $self->navHash("type_", 1); } +sub comesfrom { my $self=shift; return $self->navHash("comesfrom_", 1); } +sub ext { my $self=shift; return $self->navHash("ext_", 1) eq 'true:'; } +sub from { my $self=shift; return $self->navHash("from_", 1); } sub goesto { my $self=shift; return $self->navHash("goesto_", 1); } -# "to" can return a comma seperated list for branches -sub to { my $self=shift; return $self->navHash("to_", 1); } sub kind { my $self=shift; return $self->navHash("kind_", 1); } +sub randomout { my $self=shift; return $self->navHash("randomout_", 1); } +sub randompick { + my $self = shift; + return $self->{NAV_MAP}->{PARM_HASH}->{$self->symb . + '.0.parameter_randompick'}; +} sub src { my $self=shift; return $self->navHash("src_", 1); @@ -1812,30 +2299,58 @@ sub symb { $self->navHash('map_id_'.$first)) . '___' . $second . '___' . $symbSrc; } -sub is_problem { +sub title { my $self=shift; return $self->navHash("title_", 1); } +sub to { my $self=shift; return $self->navHash("to_", 1); } + +=pod + +B<Predicate Testing the Resource> + +These methods are shortcuts to deciding if a given resource has a given property. + +=over 4 + +=item * B<is_map>: Returns true if the resource is a map type. + +=item * B<is_problem>: Returns true if the resource is a problem type, false otherwise. (Looks at the extension on the src field; might need more to work correctly.) + +=item * B<is_page>: Returns true if the resource is a page. + +=item * B<is_problem>: Returns true if the resource is a problem. + +=item * B<is_sequence>: Returns true if the resource sequence. + +=back + +=cut + + +sub is_html { my $self=shift; my $src = $self->src(); - return ($src =~ /problem$/); + return ($src =~ /html$/); } -sub is_html { +sub is_map { my $self=shift; return defined($self->navHash("is_map_", 1)); } +sub is_page { my $self=shift; my $src = $self->src(); - return ($src =~ /html$/); + return ($src =~ /page$/); } -sub is_sequence { +sub is_problem { my $self=shift; my $src = $self->src(); - return ($src =~ /sequence$/); + return ($src =~ /problem$/); } -sub is_page { +sub is_sequence { my $self=shift; my $src = $self->src(); - return ($src =~ /page$/); + return ($src =~ /sequence$/); } + # Move this into POD: In order to use these correctly, courseopt # and useropt need to be generated sub parmval { @@ -1845,14 +2360,26 @@ sub parmval { return $self->{NAV_MAP}->parmval($part.'.'.$what, $self->symb()); } -##### -# Map Queries -##### +=pod -# These methods relate to whether or not the resource is a map, and the -# attributes of that map. +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>). + +=over 4 + +=item * B<map_finish>: Returns a reference to a resource object corresponding to the finish resource of the map. + +=item * B<map_pc>: Returns the pc value of the map, which is the first number that appears in the resource ID of the resources in the map, and is the number that appears around the middle of the symbs of the resources in that map. + +=item * B<map_start>: Returns a reference to a resource object corresponding to the start resource of the map. + +=item * B<map_type>: Returns a string with the type of the map in it. + +=back + +=cut -sub is_map { my $self=shift; return defined($self->navHash("is_map_", 1)); } sub map_finish { my $self = shift; my $src = $self->src(); @@ -1860,6 +2387,11 @@ sub map_finish { $res = $self->{NAV_MAP}->getById($res); return $res; } +sub map_pc { + my $self = shift; + my $src = $self->src(); + return $self->navHash("map_pc_$src", 0); +} sub map_start { my $self = shift; my $src = $self->src(); @@ -1867,11 +2399,6 @@ sub map_start { $res = $self->{NAV_MAP}->getById($res); return $res; } -sub map_pc { - my $self = shift; - my $src = $self->src(); - return $self->navHash("map_pc_$src", 0); -} sub map_type { my $self = shift; my $pc = $self->map_pc(); @@ -1894,7 +2421,7 @@ sub map_type { =head2 Resource Parameters -In order to use the resource parameters correctly, the nav map must have been instantiated with genCourseAndUserOptions set to true, so the courseopt and useropt is read correctly. Then, you can call these functions to get the relevant parameters for the resource. Each function defaults to "part 0", but can be directed to another part by passing the part as the second parameter. +In order to use the resource parameters correctly, the nav map must have been instantiated with genCourseAndUserOptions set to true, so 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 won't have to update their code.) @@ -1916,6 +2443,8 @@ These methods are responsible for gettin =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. @@ -1961,14 +2490,6 @@ sub tol { (my $self, my $part) = @_; return $self->parmval("tol", $part); } -sub type { - (my $self, my $part) = @_; - return $self->parmval("type", $part); -} -sub weight { - (my $self, my $part) = @_; - return $self->parmval("weight", $part); -} sub tries { my $self = shift; my $part = shift; @@ -1981,13 +2502,21 @@ sub tries { if (!defined($tries)) {return '0';} return $tries; } +sub type { + (my $self, my $part) = @_; + return $self->parmval("type", $part); +} +sub weight { + (my $self, my $part) = @_; + return $self->parmval("weight", $part); +} # Multiple things need this sub getReturnHash { my $self = shift; if (!defined($self->{RETURN_HASH})) { - my %tmpHash = &Apache::lonnet::restore($self->symb()); + my %tmpHash = &Apache::lonnet::restore($self->symb()); $self->{RETURN_HASH} = \%tmpHash; } } @@ -2014,9 +2543,33 @@ Misc. functions for the resource. =over 4 -=item * B<parts>(): Returns a list reference containing sorted strings corresponding to each part of the problem. To count the number of parts, use the list in a scalar context, and subtract one if greater then two. (One part problems have a part 0. Multi-parts have a part 0, plus a part for each part. You may or may not wish to filter out part 0.) +=item * B<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<getFeedback>: Gets the feedback for the resource and returns the raw feedback string for the resource, or the null string if there is no feedback or the email data was not extracted when the nav map was constructed. Usually used like this: + + for (split(/\,/, $res->getFeedback())) { + my $link = &Apache::lonnet::escape($_); + ... + +and use the link as appropriate. + +=cut + +sub hasDiscussion { + my $self = shift; + return $self->{NAV_MAP}->hasDiscussion($self->symb()); +} + +sub getFeedback { + my $self = shift; + return $self->{NAV_MAP}->getFeedback($self->src()); +} + +=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<countParts>(): Returns the number of parts of the problem a student can answer. Thus, for single part problems, returns 1. For multipart, it returns the number of parts in the problem, not including psuedo-part 0. +=item * B<countParts>(): Returns the number of parts of the problem a student can answer. Thus, for single part problems, returns 1. For multipart, it returns the number of parts in the problem, not including psuedo-part 0. Thus, B<parts> may return an array with fewer parts in it then countParts might lead you to believe. =back @@ -2025,6 +2578,8 @@ Misc. functions for the resource. sub parts { my $self = shift; + if ($self->ext) { return ['0']; } + $self->extractParts(); return $self->{PARTS}; } @@ -2033,8 +2588,12 @@ sub countParts { my $self = shift; my $parts = $self->parts(); - - if (scalar(@{$parts}) == 1) { return 1;} + + if ($self->{RESOURCE_ERROR}) { + return 0; + } + + if (scalar(@{$parts}) < 2) { return 1;} return scalar(@{$parts}) - 1; } @@ -2044,20 +2603,30 @@ sub extractParts { my $self = shift; return if ($self->{PARTS}); + return if ($self->ext); $self->{PARTS} = []; - # Retrieve part count - foreach (split(/\,/,&Apache::lonnet::metadata($self->src(), - 'allpossiblekeys'))) { - if ($_ =~ /^parameter\_(.*)\_opendate$/) { - push @{$self->{PARTS}}, $1; + # Retrieve part count, if this is a problem + if ($self->is_problem()) { + my $metadata = &Apache::lonnet::metadata($self->src(), 'allpossiblekeys'); + if (!$metadata) { + $self->{RESOURCE_ERROR} = 1; + $self->{PARTS} = []; + return; + } + + foreach (split(/\,/,$metadata)) { + if ($_ =~ /^parameter\_(.*)\_opendate$/) { + push @{$self->{PARTS}}, $1; + } } + + + # Is this possible to do in one line? - Jeremy + my @sortedParts = sort @{$self->{PARTS}}; + $self->{PARTS} = \@sortedParts; } - - # Is this possible to do in one line? - Jeremy - my @sortedParts = sort @{$self->{PARTS}}; - $self->{PARTS} = \@sortedParts; return; } @@ -2076,12 +2645,16 @@ Idiomatic usage of these two methods wou my $dateStatus = $resource->getDateStatus($_); my $completionStatus = $resource->getCompletionStatus($_); + or + + my $status = $resource->status($_); + ... use it here ... } =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, with the following possible results: +=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 @@ -2093,6 +2666,7 @@ B<Date Codes> =item * B<OPEN>: Open and not yet due. + =item * B<PAST_DUE_ANSWER_LATER>: 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. @@ -2140,10 +2714,10 @@ sub getDateStatus { # should this be the same as "open later"? think multipart. return $self->NOTHING_SET; } - if (!$open || $now < $open) {return $self->OPEN_LATER}; - if (!$due || $now < $due) {return $self->OPEN}; - if ($answer && $now < $answer) {return $self->PAST_DUE_ANSWER_LATER}; - if ($answer) { return $self->ANSWER_OPEN; }; + if (!$open || $now < $open) {return $self->OPEN_LATER} + if (!$due || $now < $due) {return $self->OPEN} + if ($answer && $now < $answer) {return $self->PAST_DUE_ANSWER_LATER} + if ($answer) { return $self->ANSWER_OPEN; } return PAST_DUE_NO_ANSWER; } @@ -2175,6 +2749,8 @@ B<Completion Codes> =item * B<NETWORK_FAILURE>: Information not available due to network failure. +=item * B<ATTEMPTED>: Attempted, and not yet graded. + =back =cut @@ -2185,6 +2761,7 @@ sub INCORRECT_BY_OVERRIDE { return 12; } sub CORRECT { return 13; } sub CORRECT_BY_OVERRIDE { return 14; } sub EXCUSED { return 15; } +sub ATTEMPTED { return 16; } sub getCompletionStatus { my $self = shift; @@ -2203,6 +2780,7 @@ sub getCompletionStatus { if ($status eq 'incorrect_attempted') {return $self->INCORRECT; } if ($status eq 'incorrect_by_override') {return $self->INCORRECT_BY_OVERRIDE; } if ($status eq 'excused') {return $self->EXCUSED; } + if ($status eq 'ungraded_attempted') {return $self->ATTEMPTED; } return $self->NOT_ATTEMPTED; } @@ -2214,27 +2792,29 @@ Along with directly returning the date o =over 4 -=item * NETWORK_FAILURE: The network has failed and the information is not available. +=item * B<NETWORK_FAILURE>: The network has failed and the information is not available. -=item * 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.) +=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".) -=item * CORRECT: For any reason at all, the part is considered correct. +=item * B<CORRECT>: For any reason at all, the part is considered correct. -=item * EXCUSED: For any reason at all, the problem is excused. +=item * B<EXCUSED>: For any reason at all, the problem is excused. -=item * PAST_DUE_NO_ANSWER: The problem is past due, not considered correct, and no answer date is set. +=item * B<PAST_DUE_NO_ANSWER>: The problem is past due, not considered correct, and no answer date is set. -=item * PAST_DUE_ANSWER_LATER: The problem is past due, not considered correct, and an answer date in the future is set. +=item * B<PAST_DUE_ANSWER_LATER>: The problem is past due, not considered correct, and an answer date in the future is set. -=item * ANSWER_OPEN: 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 * OPEN_LATER: The problem is not yet open. +=item * B<OPEN_LATER>: The problem is not yet open. -=item * TRIES_LEFT: The problem is open, has been tried, is not correct, but there are tries left. +=item * B<TRIES_LEFT>: The problem is open, has been tried, is not correct, but there are tries left. -=item * INCORRECT: The problem is open, and all tries have been used without getting the correct answer. +=item * B<INCORRECT>: The problem is open, and all tries have been used without getting the correct answer. -=item * OPEN: The item is open and not yet tried. +=item * B<OPEN>: The item is open and not yet tried. + +=item * B<ATTEMPTED>: The problem has been attempted. =back @@ -2258,7 +2838,11 @@ sub status { # There are a few whole rows we can dispose of: if ($completionStatus == CORRECT || $completionStatus == CORRECT_BY_OVERRIDE ) { - return CORRECT(); + return CORRECT; + } + + if ($completionStatus == ATTEMPTED) { + return ATTEMPTED; } # If it's EXCUSED, then return that no matter what @@ -2270,11 +2854,11 @@ sub status { return NOTHING_SET; } - # Now we're down to a 3 (incorrect, incorrect_override, not_attempted) - # by 4 matrix (date status). + # Now we're down to a 4 (incorrect, incorrect_override, not_attempted) + # by 4 matrix (date statuses). if ($dateStatus == PAST_DUE_ANSWER_LATER || - $dateStatus == PAST_DUE_NO_ANSWER) { + $dateStatus == PAST_DUE_NO_ANSWER ) { return $dateStatus; } @@ -2292,7 +2876,7 @@ sub status { # If it's WRONG... if ($completionStatus == INCORRECT || $completionStatus == INCORRECT_BY_OVERRIDE) { # and there are TRIES LEFT: - if ($self->tries() < $self->maxtries()) { + if ($self->tries($part) < $self->maxtries($part) || !$self->maxtries($part)) { return TRIES_LEFT; } return INCORRECT; # otherwise, return orange; student can't fix this @@ -2308,32 +2892,55 @@ sub status { =over 4 -=item * B<getNext>(): Gets the next resource in the navmap after this one. +=item * B<getNext>($alreadySeenHashRef): Retreive an array of the possible next resources after this one. Always returns an array, even in the one- or zero-element case. The "alreadySeenHashRef" is an optional parameter that can be passed in to the method. If $$alreadySeenHashRef{$res->id()} is true in that hash, getNext will not return it in the list. In other words, you can use it to suppress resources you've already seen in the getNext method directly. -=cut +=item * B<getPrevious>($alreadySeenHashRef): Retreive an array of the possible previous resources from this one. Always returns an array, even in the one- or zero-element case. $alreadySeenHashRef is the same as in getNext. -# For the simple single-link case, to get from a resource to the next -# resource, you need to look up the "to_" link in the nav hash, then -# follow that with the "goesto_" link. +=cut sub getNext { my $self = shift; my $alreadySeenHash = shift; my @branches; my $to = $self->to(); - foreach my $branch ( split(/\,/, $to) ) { + foreach my $branch ( split(/,/, $to) ) { my $choice = $self->{NAV_MAP}->getById($branch); my $next = $choice->goesto(); $next = $self->{NAV_MAP}->getById($next); - # Don't remember it if we've already seen it + # Don't remember it if we've already seen it or if + # the student doesn't have browse priviledges + my $browsePriv = &Apache::lonnet::allowed('bre', $self->src); if (!defined($alreadySeenHash) || - !defined($alreadySeenHash->{$next->{ID}})) { + !defined($alreadySeenHash->{$next->{ID}}) || + ($browsePriv ne '2' && $browsePriv ne 'F')) { push @branches, $next; } } return \@branches; } + +sub getPrevious { + my $self = shift; + my @alreadySeen = shift; + my @branches; + my $from = $self->from(); + foreach my $branch ( split /,/, $from) { + my $choice = $self->{NAV_MAP}->getById($branch); + my $prev = $choice->comesfrom(); + $prev = $self->{NAV_MAP}->getById($prev); + + # Skip it if we've already seen it or the user doesn't have + # browse privs + my $browsePriv = &Apache::lonnet::allowed('bre', $self->src); + if (!defined($alreadySeenHash) || + !defined($alreadySeenHash->{$next->{ID}}) || + ($browsePriv ne '2' && $browsePriv ne 'F')) { + push @branches, $next; + } + } + return \@branches; +} =pod