--- loncom/interface/lonnavmaps.pm 2001/01/30 22:26:33 1.12 +++ loncom/interface/lonnavmaps.pm 2003/06/10 19:44:16 1.197 @@ -1,6 +1,30 @@ # The LearningOnline Network with CAPA # Navigate Maps Handler # +# $Id: lonnavmaps.pm,v 1.197 2003/06/10 19:44:16 bowersj2 Exp $ +# +# Copyright Michigan State University Board of Trustees +# +# This file is part of the LearningOnline Network with CAPA (LON-CAPA). +# +# LON-CAPA is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# LON-CAPA is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with LON-CAPA; if not, write to the Free Software +# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +# +# /home/httpd/html/adm/gpl.txt +# +# http://www.lon-capa.org/ +# # (Page Handler # # (TeX Content Handler @@ -9,62 +33,1861 @@ # 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 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 +# Oct-Nov Jeremy Bowers +# YEAR=2003 +# Jeremy Bowers ... lots of days package Apache::lonnavmaps; use strict; use Apache::Constants qw(:common :http); -use Apache::lonnet(); -use HTML::TokeParser; +use Apache::loncommon(); +use Apache::lonmenu(); +use POSIX qw (floor strftime); +use Data::Dumper; # for debugging, not always used + +# symbolic constants +sub SYMB { return 1; } +sub URL { return 2; } +sub NOTHING { return 3; } + +# Some data + +my $resObj = "Apache::lonnavmaps::resource"; + +# Keep these mappings in sync with lonquickgrades, which uses the colors +# instead of the icons. +my %statusIconMap = + ( $resObj->NETWORK_FAILURE => '', + $resObj->NOTHING_SET => '', + $resObj->CORRECT => 'navmap.correct.gif', + $resObj->EXCUSED => 'navmap.correct.gif', + $resObj->PAST_DUE_NO_ANSWER => 'navmap.wrong.gif', + $resObj->PAST_DUE_ANSWER_LATER => 'navmap.wrong.gif', + $resObj->ANSWER_OPEN => 'navmap.wrong.gif', + $resObj->OPEN_LATER => '', + $resObj->TRIES_LEFT => 'navmap.open.gif', + $resObj->INCORRECT => 'navmap.wrong.gif', + $resObj->OPEN => 'navmap.open.gif', + $resObj->ATTEMPTED => 'navmap.open.gif', + $resObj->ANSWER_SUBMITTED => '' ); + +my %iconAltTags = + ( 'navmap.correct.gif' => 'Correct', + 'navmap.wrong.gif' => 'Incorrect', + 'navmap.open.gif' => 'Open' ); + +# Defines a status->color mapping, null string means don't color +my %colormap = + ( $resObj->NETWORK_FAILURE => '', + $resObj->CORRECT => '', + $resObj->EXCUSED => '#3333FF', + $resObj->PAST_DUE_ANSWER_LATER => '', + $resObj->PAST_DUE_NO_ANSWER => '', + $resObj->ANSWER_OPEN => '#006600', + $resObj->OPEN_LATER => '', + $resObj->TRIES_LEFT => '', + $resObj->INCORRECT => '', + $resObj->OPEN => '', + $resObj->NOTHING_SET => '' ); +# 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"; + +sub handler { + my $r = shift; + real_handler($r); +} + +sub real_handler { + my $r = shift; + + # Handle header-only request + if ($r->header_only) { + if ($ENV{'browser.mathml'}) { + $r->content_type('text/xml'); + } else { + $r->content_type('text/html'); + } + $r->send_http_header; + return OK; + } + + # Send header, don't cache this page + if ($ENV{'browser.mathml'}) { + $r->content_type('text/xml'); + } else { + $r->content_type('text/html'); + } + &Apache::loncommon::no_cache($r); + $r->send_http_header; + + # Create the nav map + my $navmap = Apache::lonnavmaps::navmap->new( + $ENV{"request.course.fn"}.".db", + $ENV{"request.course.fn"}."_parms.db", 1, 1); + + + if (!defined($navmap)) { + my $requrl = $r->uri; + $ENV{'user.error.msg'} = "$requrl:bre:0:0:Course not initialized"; + return HTTP_NOT_ACCEPTABLE; + } + + $r->print("\n"); + $r->print("Navigate Course Contents"); +# ------------------------------------------------------------ Get query string + &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['register']); + +# ----------------------------------------------------- Force menu registration + my $addentries=''; + if ($ENV{'form.register'}) { + $addentries=' onLoad="'.&Apache::lonmenu::loadevents(). + '" onUnload="'.&Apache::lonmenu::unloadevents().'"'; + $r->print(&Apache::lonmenu::registerurl(1)); + } + + # Header + $r->print(''. + &Apache::loncommon::bodytag('Navigate Course Contents','', + $addentries,'','',$ENV{'form.register'})); + $r->print(''); + + $r->rflush(); + + # Now that we've displayed some stuff to the user, init the navmap + $navmap->init(); + + $r->print('
 '); + $r->rflush(); + + # Check that it's defined + if (!($navmap->courseMapDefined())) { + $r->print('Coursemap undefined.' . + ''); + return OK; + } + + # See if there's only one map in the top-level, if we don't + # already have a filter... if so, automatically display it + if ($ENV{QUERY_STRING} !~ /filter/) { + my $iterator = $navmap->getIterator(undef, undef, undef, 0); + my $depth = 1; + $iterator->next(); + my $curRes = $iterator->next(); + my $sequenceCount = 0; + my $sequenceId; + while ($depth > 0) { + if ($curRes == $iterator->BEGIN_MAP()) { $depth++; } + if ($curRes == $iterator->END_MAP()) { $depth--; } + + if (ref($curRes) && $curRes->is_sequence()) { + $sequenceCount++; + $sequenceId = $curRes->map_pc(); + } + + $curRes = $iterator->next(); + } + + if ($sequenceCount == 1) { + # The automatic iterator creation in the render call + # will pick this up. We know the condition because + # the defined($ENV{'form.filter'}) also ensures this + # is a fresh call. + $ENV{'form.filter'} = "$sequenceId"; + } + } + + my $jumpToFirstHomework = 0; + # Check to see if the student is jumping to next open, do-able problem + if ($ENV{QUERY_STRING} eq 'jumpToFirstHomework') { + $jumpToFirstHomework = 1; + # Find the next homework problem that they can do. + my $iterator = $navmap->getIterator(undef, undef, undef, 1); + my $depth = 1; + $iterator->next(); + my $curRes = $iterator->next(); + my $foundDoableProblem = 0; + my $problemRes; + + while ($depth > 0 && !$foundDoableProblem) { + if ($curRes == $iterator->BEGIN_MAP()) { $depth++; } + if ($curRes == $iterator->END_MAP()) { $depth--; } + + if (ref($curRes) && $curRes->is_problem()) { + my $status = $curRes->status(); + if ($curRes->completable()) { + $problemRes = $curRes; + $foundDoableProblem = 1; + + # Pop open all previous maps + my $stack = $iterator->getStack(); + pop @$stack; # last resource in the stack is the problem + # itself, which we don't need in the map stack + my @mapPcs = map {$_->map_pc()} @$stack; + $ENV{'form.filter'} = join(',', @mapPcs); + + # Mark as both "here" and "jump" + $ENV{'form.postsymb'} = $curRes->symb(); + } + } + } continue { + $curRes = $iterator->next(); + } + + # If we found no problems, print a note to that effect. + if (!$foundDoableProblem) { + $r->print("All homework assignments have been completed.

"); + } + } else { + $r->print("" . + "Go To My First Homework Problem
"); + } + + my $suppressEmptySequences = 0; + my $filterFunc = undef; + # Display only due homework. + my $showOnlyHomework = 0; + if ($ENV{QUERY_STRING} eq 'showOnlyHomework') { + $showOnlyHomework = 1; + $suppressEmptySequences = 1; + $filterFunc = sub { my $res = shift; + return $res->completable() || $res->is_sequence(); + }; + $r->print("

Uncompleted Homework

"); + $ENV{'form.filter'} = ''; + $ENV{'form.condition'} = 1; + } else { + $r->print("" . + "Show Only Uncompleted Homework
"); + } + + # renderer call + my $renderArgs = { 'cols' => [0,1,2,3], + 'url' => '/adm/navmaps', + 'navmap' => $navmap, + 'suppressNavmap' => 1, + 'suppressEmptySequences' => $suppressEmptySequences, + 'filterFunc' => $filterFunc, + 'r' => $r}; + my $render = render($renderArgs); + $navmap->untieHashes(); + + # If no resources were printed, print a reassuring message so the + # user knows there was no error. + if ($renderArgs->{'counter'} == 0) { + if ($showOnlyHomework) { + $r->print("

All homework is currently completed.

"); + } else { # both jumpToFirstHomework and normal use the same: course must be empty + $r->print("

This course is empty.

"); + } + } + + $r->print(""); + $r->rflush(); + + return OK; +} + +# Convenience functions: Returns a string that adds or subtracts +# the second argument from the first hash, appropriate for the +# query string that determines which folders to recurse on +sub addToFilter { + my $hashIn = shift; + my $addition = shift; + my %hash = %$hashIn; + $hash{$addition} = 1; + + return join (",", keys(%hash)); +} + +sub removeFromFilter { + my $hashIn = shift; + my $subtraction = shift; + my %hash = %$hashIn; + + delete $hash{$subtraction}; + return join(",", keys(%hash)); +} + +# Convenience function: Given a stack returned from getStack on the iterator, +# return the correct src() value. +# Later, this should add an anchor when we start putting anchors in pages. +sub getLinkForResource { + my $stack = shift; + my $res; + + # Check to see if there are any pages in the stack + foreach $res (@$stack) { + if (defined($res) && $res->is_page()) { + return $res->src(); + } + } + + # Failing that, return the src of the last resource that is defined + # (when we first recurse on a map, it puts an undefined resource + # on the bottom because $self->{HERE} isn't defined yet, and we + # want the src for the map anyhow) + foreach (@$stack) { + if (defined($_)) { $res = $_; } + } + + return $res->src(); +} + +# Convenience function: This seperates the logic of how to create +# the problem text strings ("Due: DATE", "Open: DATE", "Not yet assigned", +# etc.) into a seperate function. It takes a resource object as the +# first parameter, and the part number of the resource as the second. +# It's basically a big switch statement on the status of the resource. + +sub getDescription { + my $res = shift; + my $part = shift; + my $status = $res->status($part); + + if ($status == $res->NETWORK_FAILURE) { + return "Having technical difficulties; please check status later"; + } + if ($status == $res->NOTHING_SET) { + return "Not currently assigned."; + } + if ($status == $res->OPEN_LATER) { + return "Open " . timeToHumanString($res->opendate($part)); + } + if ($status == $res->OPEN) { + if ($res->duedate($part)) { + return "Due " . timeToHumanString($res->duedate($part)); + } else { + return "Open, no due date"; + } + } + if ($status == $res->PAST_DUE_ANSWER_LATER) { + return "Answer open " . timeToHumanString($res->answerdate($part)); + } + if ($status == $res->PAST_DUE_NO_ANSWER) { + return "Was due " . timeToHumanString($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 $triesString"; + } + } + if ($status == $res->ANSWER_SUBMITTED) { + return 'Answer submitted'; + } +} + +# Convenience function, so others can use it: Is the problem due in less then +# 24 hours, and still can be done? + +sub dueInLessThen24Hours { + my $res = shift; + my $part = shift; + my $status = $res->status($part); + + return ($status == $res->OPEN() || $status == $res->ATTEMPTED() || + $status == $res->TRIES_LEFT()) && + $res->duedate() && $res->duedate() < time()+(24*60*60) && + $res->duedate() > time(); +} + +# Convenience function, so others can use it: Is there only one try remaining for the +# part, with more then one try to begin with, not due yet and still can be done? +sub lastTry { + my $res = shift; + my $part = shift; + + my $tries = $res->tries($part); + my $maxtries = $res->maxtries($part); + return $tries && $maxtries && $maxtries > 1 && + $maxtries - $tries == 1 && $res->duedate() && + $res->duedate() > time(); +} + +# This puts a human-readable name on the ENV variable. + +sub advancedUser { + return $ENV{'request.role.adv'}; +} + + +# timeToHumanString takes a time number and converts it to a +# human-readable representation, meant to be used in the following +# manner: +# print "Due $timestring" +# print "Open $timestring" +# print "Answer available $timestring" +# Very, very, very, VERY English-only... goodness help a localizer on +# this func... +sub timeToHumanString { + my ($time) = @_; + # zero, '0' and blank are bad times + if (!$time) { + return 'never'; + } + + my $now = time(); + + my @time = localtime($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; + } + + if ( $delta > 0 ) { + + my $tense = $inPast ? " ago" : ""; + my $prefix = $inPast ? "" : "in "; + + # Less then a minute + if ( $delta < $minute ) { + if ($delta == 1) { return "${prefix}1 second$tense"; } + return "$prefix$delta seconds$tense"; + } + + # Less then an hour + 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; + } +} + + +=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 Object: 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 presents, +instead of passing it arguments as is normal, pass it in an anonymous +hash with the given options. This is because there is no obvious order +you may wish to override these in and a hash is easier to read and +understand then "undef, undef, undef, 1, undef, undef, renderButton, +undef, 0" when you mostly want default behaviors. + +The package provides a function called 'render', called as +Apache::lonnavmaps::renderer->render({}). + +=head2 Overview of Columns + +The renderer will build an HTML table for the navmap and return +it. The table is consists of several columns, and a row for each +resource (or possibly each part). You tell the renderer how many +columns to create and what to place in each column, optionally using +one or more of the preparent 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 +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. + +The pre-packaged column names are refered to by constants in the +Apache::lonnavmaps::renderer namespace. The following currently exist: + +=over 4 + +=item * B: + +The general info about the resource: Link, icon for the type, etc. The +first column in the standard nav map display. This column also accepts +the following parameter in the renderer hash: + +=over 4 + +=item * B: + +If true, the resource will not be linked. Default: false, resource +will have links. + +=item * B: + +If true (default), the resource will show a part count if the full +part list is not displayed. If false, the resource will never show a +part count. + +=item * B: + +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: + +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: + +An icon for the status of a problem, with four possible states: +Correct, incorrect, open, or none (not open yet, not a problem). The +third column of the standard navmap. + +=item B: + +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. + +=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 '' . $resource->{ID} . ' ' . $part . ''; } + return '' . $resource->{ID} . ''; + } + +Note these functions are responsible for the TD tags, which allow them +to override vertical and horizontal alignment, etc. + +=head2 Parameters + +Most of these parameters are only useful if you are *not* using the +folder interface (i.e., the default first column), which is probably +the common case. If you are using this interface, then 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: + +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: + +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: + +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: + +The standard Apache response object. This must be passed to the +renderer or the course hash will be locked. + +=item * B: + +An array reference + +=item * B: + +A flag. If yes (default), 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: + +A flag. If yes (default), 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: + +A string identifying the URL to place the anchor 'curloc' at. Default +to no anchor at all. 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: + +A Symb identifying where to place the 'here' marker. Default empty, +which means no marker. + +=item * B: + +A string identifying the indentation string to use. By default, this +is a 25 pixel whitespace image with no alt text. + +=item * B: + +A string which will be prepended to the query string used when the +folders are opened or closed. + +=item * B: + +The url the folders will link to, which should be the current +page. Required if the resource info column is shown. + +=item * B: + +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: + +If true, print the key that appears on the top of the standard +navmaps. Default is false. + +=item * B: + +If true, print the "Close all folders" or "open all folders" +links. Default is true. + +=item * B: + +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. By default, all resources +are shown. + +=item * B: + +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. + +=item * B: + +If true, will not display Navigate Content resources. Default to +false. + +=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: + +If you want to know how many rows were printed, the 'counter' element +of the hash passed into the render function will contain the +count. You may want to check whether any resources were printed at +all. + +=over 4 + +=back + +=cut + +sub resource { return 0; } +sub communication_status { return 1; } +sub quick_status { return 2; } +sub long_status { return 3; } + +# Data for render_resource + +sub render_resource { + my ($resource, $part, $params) = @_; + + my $nonLinkedText = ''; # stuff after resource title not in link + + my $link = $params->{"resourceLink"}; + my $src = $resource->src(); + my $it = $params->{"iterator"}; + my $filter = $it->{FILTER}; + + my $title = $resource->compTitle(); + if ($src =~ /^\/uploaded\//) { + $nonLinkedText=$title; + $title = ''; + } + my $partLabel = ""; + my $newBranchText = ""; + + # If this is a new branch, label it so + if ($params->{'isNewBranch'}) { + $newBranchText = ""; + } + + # links to open and close the folder + my $linkopen = ""; + my $linkclose = ""; + + # Default icon: HTML page + my $icon = ""; + + if ($resource->is_problem()) { + if ($part eq '0' || $params->{'condensed'}) { + $icon = ''; + } else { + $icon = $params->{'indentString'}; + } + } + + # Display the correct map icon to open or shut map + if ($resource->is_map()) { + my $mapId = $resource->map_pc(); + my $nowOpen = !defined($filter->{$mapId}); + if ($it->{CONDITION}) { + $nowOpen = !$nowOpen; + } + + if (!$params->{'resource_no_folder_link'}) { + $icon = 'navmap.folder.' . ($nowOpen ? 'closed' : 'open') . '.gif'; + $icon = ""; + + $linkopen = "{'queryString'} . '&filter='; + $linkopen .= ($nowOpen xor $it->{CONDITION}) ? + addToFilter($filter, $mapId) : + removeFromFilter($filter, $mapId); + $linkopen .= "&condition=" . $it->{CONDITION} . '&hereType=' + . $params->{'hereType'} . '&here=' . + &Apache::lonnet::escape($params->{'here'}) . + '&jump=' . + &Apache::lonnet::escape($resource->symb()) . + "&folderManip=1'>"; + } else { + # Don't allow users to manipulate folder + $icon = 'navmap.folder.' . ($nowOpen ? 'closed' : 'open') . + '.nomanip.gif'; + $icon = ""; + + $linkopen = ""; + $linkclose = ""; + } + } + + if ($resource->randomout()) { + $nonLinkedText .= ' (hidden) '; + } + + # We're done preparing and finally ready to start the rendering + my $result = ""; + + 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 = '> '; + $curMarkerEnd = '<'; + $params->{'displayedHereMarker'} = 1; + } + + if ($resource->is_problem() && $part ne '0' && + !$params->{'condensed'}) { + $partLabel = " (Part $part)"; + $title = ""; + } + + if ($params->{'condensed'} && $resource->countParts() > 1) { + $nonLinkedText .= ' (' . $resource->countParts() . ' parts)'; + } + + if (!$params->{'resource_nolink'}) { + $result .= " $curMarkerBegin$title$partLabel$curMarkerEnd $nonLinkedText"; + } else { + $result .= " $curMarkerBegin$title$partLabel$curMarkerEnd $nonLinkedText"; + } + + return $result; +} + +sub render_communication_status { + my ($resource, $part, $params) = @_; + my $discussionHTML = ""; my $feedbackHTML = ""; my $errorHTML = ""; + + my $link = $params->{"resourceLink"}; + my $linkopen = ""; + my $linkclose = ""; + + if ($resource->hasDiscussion()) { + $discussionHTML = $linkopen . + '' . + $linkclose; + } + + if ($resource->getFeedback()) { + my $feedback = $resource->getFeedback(); + foreach (split(/\,/, $feedback)) { + if ($_) { + $feedbackHTML .= ' ' + . ''; + } + } + } + + if ($resource->getErrors()) { + my $errors = $resource->getErrors(); + foreach (split(/,/, $errors)) { + if ($_) { + $errorHTML .= ' ' + . ''; + } + } + } + + if ($params->{'multipart'} && $part != '0') { + $discussionHTML = $feedbackHTML = $errorHTML = ''; + } + + return "$discussionHTML$feedbackHTML$errorHTML "; + +} +sub render_quick_status { + my ($resource, $part, $params) = @_; + my $result = ""; + my $firstDisplayed = !$params->{'condensed'} && + $params->{'multipart'} && $part eq "0"; + + my $link = $params->{"resourceLink"}; + my $linkopen = ""; + my $linkclose = ""; + + if ($resource->is_problem() && + !$firstDisplayed) { + my $icon = $statusIconMap{$resource->status($part)}; + my $alt = $iconAltTags{$icon}; + if ($icon) { + $result .= "$linkopen$alt$linkclose\n"; + } else { + $result .= " \n"; + } + } else { # not problem, no icon + $result .= " \n"; + } + + return $result; +} +sub render_long_status { + my ($resource, $part, $params) = @_; + my $result = "\n"; + my $firstDisplayed = !$params->{'condensed'} && + $params->{'multipart'} && $part eq "0"; + + my $color; + if ($resource->is_problem() && ($resource->countParts() <= 1 || $part ne '') ) { + $color = $colormap{$resource->status}; + + if (dueInLessThen24Hours($resource, $part) || + lastTry($resource, $part)) { + $color = $hurryUpColor; + } + } + + if ($resource->kind() eq "res" && + $resource->is_problem() && + !$firstDisplayed) { + if ($color) {$result .= ""; } + $result .= getDescription($resource, $part); + if ($color) {$result .= ""; } + } + if ($resource->is_map() && advancedUser() && $resource->randompick()) { + $result .= '(randomly select ' . $resource->randompick() .')'; + } + + return $result; +} + +my @preparedColumns = (\&render_resource, \&render_communication_status, + \&render_quick_status, \&render_long_status); + +sub setDefault { + my ($val, $default) = @_; + if (!defined($val)) { return $default; } + return $val; +} + +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 $mustCloseNavMap = 0; + my $navmap; + if (defined($args->{'navmap'})) { + $navmap = $args->{'navmap'}; + } + + my $r = $args->{'r'}; + my $queryString = $args->{'queryString'}; + my $jump = $args->{'jump'}; + my $here = $args->{'here'}; + my $suppressNavmap = setDefault($args->{'suppressNavmap'}, 0); + my $currentJumpDelta = 2; # change this to change how many resources are displayed + # before the current resource when using #current + + # If we were passed 'here' information, we are not rendering + # after a folder manipulation, and we were not passed an + # iterator, make sure we open the folders to show the "here" + # marker + my $filterHash = {}; + # Figure out what we're not displaying + foreach (split(/\,/, $ENV{"form.filter"})) { + if ($_) { + $filterHash->{$_} = "1"; + } + } + + # 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( + $ENV{"request.course.fn"}.".db", + $ENV{"request.course.fn"}."_parms.db", 1, 1); + $mustCloseNavMap = 1; + } + $navmap->init(); + + # Step two: Locate what kind of here marker is necessary + # Determine where the "here" marker is and where the screen jumps to. + + if ($ENV{'form.postsymb'}) { + $here = $jump = $ENV{'form.postsymb'}; + } elsif ($ENV{'form.postdata'}) { + # couldn't find a symb, is there a URL? + my $currenturl = $ENV{'form.postdata'}; + #$currenturl=~s/^http\:\/\///; + #$currenturl=~s/^[^\/]+//; + + $here = $jump = &Apache::lonnet::symbread($currenturl); + } + + # Step three: Ensure the folders are open + my $mapIterator = $navmap->getIterator(undef, undef, undef, 1); + my $depth = 1; + $mapIterator->next(); # discard the first BEGIN_MAP + my $curRes = $mapIterator->next(); + my $found = 0; + + # We only need to do this if we need to open the maps to show the + # current position. This will change the counter so we can't count + # for the jump marker with this loop. + while ($depth > 0 && !$found) { + if ($curRes == $mapIterator->BEGIN_MAP()) { $depth++; } + if ($curRes == $mapIterator->END_MAP()) { $depth--; } + + if (ref($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; + } + + $curRes = $mapIterator->next(); + } + } + + if ( !defined($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)) { + $navmap = Apache::lonnavmaps::navmap->new($r, + $ENV{"request.course.fn"}.".db", + $ENV{"request.course.fn"}."_parms.db", 1, 1); + $mustCloseNavMap = 1; + } + # Paranoia: Make sure it's ready + $navmap->init(); + + # See if we're being passed a specific map + if ($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); + } + } + + # (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 $depth = 1; + $mapIterator->next(); + my $curRes = $mapIterator->next(); + my $foundJump = 0; + my $counter = 0; + + while ($depth > 0 && !$foundJump) { + if ($curRes == $mapIterator->BEGIN_MAP()) { $depth++; } + if ($curRes == $mapIterator->END_MAP()) { $depth--; } + if (ref($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; + } + + $curRes = $mapIterator->next(); + } + + 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 .= ''; + my $date=localtime; + $result.=''; + if ($navmap->{LAST_CHECK}) { + $result .= + ' New discussion since '. + strftime("%A, %b %e at %I:%M %P", localtime($navmap->{LAST_CHECK})). + ''; + } else { + $result .= ''; + } + + $result .= '
Key:    '. + ' New message (click to open)

'. + '

  '. + ' Discussions'. + '   New message (click to open)'. + '
'; + } + + if ($printCloseAll && !$args->{'resource_no_folder_link'}) { + if ($condition) { + $result.="Close All Folders"; + } else { + $result.="Open All Folders"; + } + $result .= "

\n"; + } + + if ($r) { + $r->print($result); + $r->rflush(); + $result = ""; + } + # End parameter setting + + # Data + $result .= '' ."\n"; + my $res = "Apache::lonnavmaps::resource"; + my %condenseStatuses = + ( $res->NETWORK_FAILURE => 1, + $res->NOTHING_SET => 1, + $res->CORRECT => 1 ); + my @backgroundColors = ("#FFFFFF", "#F6F6F6"); + + # Shared variables + $args->{'counter'} = 0; # counts the rows + $args->{'indentLevel'} = 0; + $args->{'isNewBranch'} = 0; + $args->{'condensed'} = 0; + $args->{'indentString'} = setDefault($args->{'indentString'}, ""); + $args->{'displayedHereMarker'} = 0; + + # If we're suppressing empty sequences, look for them here. Use DFS for speed, + # since structure actually doesn't matter, except what map has what resources. + if ($args->{'suppressEmptySequences'}) { + my $dfsit = Apache::lonnavmaps::DFSiterator->new($navmap, + $it->{FIRST_RESOURCE}, + $it->{FINISH_RESOURCE}, + {}, undef, 1); + $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_sequence()) { + $curRes->{DATA}->{HAS_VISIBLE_CHILDREN} = 0; + # Sequences themselves do not count as visible children, + # unless those sequences also have visible children. + # This means if a sequence appears, there's a "promise" + # that there's something under it if you open it, somewhere. + } else { + # Not a sequence: if it's filtered, ignore it, otherwise + # rise up the stack and mark the sequences as having children + if (&$filterFunc($curRes)) { + for my $sequence (@{$dfsit->getStack()}) { + $sequence->{DATA}->{HAS_VISIBLE_CHILDREN} = 1; + } + } + } + } + } continue { + $curRes = $dfsit->next(); + } + } + + my $displayedJumpMarker = 0; + # Set up iteration. + $depth = 1; + $it->next(); # discard initial BEGIN_MAP + $curRes = $it->next(); + my $now = time(); + my $in24Hours = $now + 24 * 60 * 60; + my $rownum = 0; + + # export "here" marker information + $args->{'here'} = $here; + + while ($depth > 0) { + if ($curRes == $it->BEGIN_MAP()) { $depth++; } + if ($curRes == $it->END_MAP()) { $depth--; } + + # Maintain indentation level. + if ($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_sequence() && $args->{'suppressEmptySequences'} && + !$curRes->{DATA}->{HAS_VISIBLE_CHILDREN}) { + next; + } + + # If we're suppressing navmaps and this is a navmap, continue on + if ($suppressNavmap && $curRes->src() =~ /^\/adm\/navmaps/) { + next; + } + + $args->{'counter'}++; + + # Does it have multiple parts? + $args->{'multipart'} = 0; + $args->{'condensed'} = 0; + my @parts; + + # Decide what parts to show. + if ($curRes->is_problem() && $showParts) { + @parts = @{$curRes->parts()}; + $args->{'multipart'} = $curRes->multipart(); + + if ($condenseParts) { # do the condensation + if (!$curRes->opendate("0")) { + @parts = (); + $args->{'condensed'} = 1; + } + if (!$args->{'condensed'}) { + # Decide whether to condense based on similarity + my $status = $curRes->status($parts[0]); + my $due = $curRes->duedate($parts[0]); + my $open = $curRes->opendate($parts[0]); + my $statusAllSame = 1; + my $dueAllSame = 1; + my $openAllSame = 1; + for (my $i = 1; $i < scalar(@parts); $i++) { + if ($curRes->status($parts[$i]) != $status){ + $statusAllSame = 0; + } + if ($curRes->duedate($parts[$i]) != $due ) { + $dueAllSame = 0; + } + if ($curRes->opendate($parts[$i]) != $open) { + $openAllSame = 0; + } + } + # $*allSame is true if all the statuses were + # the same. Now, if they are all the same and + # match one of the statuses to condense, or they + # are all open with the same due date, or they are + # all OPEN_LATER with the same open date, display the + # status of the first non-zero part (to get the 'correct' + # status right, since 0 is never 'correct' or 'open'). + if (($statusAllSame && defined($condenseStatuses{$status})) || + ($dueAllSame && $status == $curRes->OPEN && $statusAllSame)|| + ($openAllSame && $status == $curRes->OPEN_LATER && $statusAllSame) ){ + @parts = ($parts[0]); + $args->{'condensed'} = 1; + } + + } + } + } + + # If the multipart problem was condensed, "forget" it was multipart + if (scalar(@parts) == 1) { + $args->{'multipart'} = 0; + } else { + # Add part 0 so we display it correctly. + unshift @parts, '0'; + } + + # Now, we've decided what parts to show. Loop through them and + # show them. + foreach my $part (@parts) { + $rownum ++; + my $backgroundColor = $backgroundColors[$rownum % scalar(@backgroundColors)]; + + $result .= " \n"; + + # Set up some data about the parts that the cols might want + my $filter = $it->{FILTER}; + my $stack = $it->getStack(); + my $src = getLinkForResource($stack); + + my $srcHasQuestion = $src =~ /\?/; + $args->{"resourceLink"} = $src. + ($srcHasQuestion?'&':'?') . + 'symb=' . &Apache::lonnet::escape($curRes->symb()); + + # Now, display each column. + foreach my $col (@$cols) { + my $colHTML = ''; + if (ref($col)) { + $colHTML .= &$col($curRes, $part, $args); + } else { + $colHTML .= &{$preparedColumns[$col]}($curRes, $part, $args); + } + + # If this is the first column and it's time to print + # the anchor, do so + if ($col == $cols->[0] && + $args->{'counter'} == $args->{'currentJumpIndex'} - + $currentJumpDelta) { + # Jam the anchor after the \n"; + $args->{'isNewBranch'} = 0; + } + + if ($r && $rownum % 20 == 0) { + $r->print($result); + $result = ""; + $r->rflush(); + } + } continue { + $curRes = $it->next(); + } + + # Print out the part that jumps to #curloc if it exists + # delay needed because the browser is processing the jump before + # it finishes rendering, so it goes to the wrong place! + # onload might be better, but this routine has no access to that. + # On mozilla, the 0-millisecond timeout seems to prevent this; + # it's quite likely this might fix other browsers, too, and + # certainly won't hurt anything. + if ($displayedJumpMarker) { + $result .= "\n"; + } + + $result .= "
tag; + # necessary for valid HTML (which Mozilla requires) + $colHTML =~ s/\>/\>\/; + $displayedJumpMarker = 1; + } + $result .= $colHTML . "\n"; + } + $result .= "
"; + + if ($r) { + $r->print($result); + $result = ""; + $r->rflush(); + } + + if ($mustCloseNavMap) { $navmap->untieHashes(); } + + return $result; +} + +1; + +package Apache::lonnavmaps::navmap; + +=pod + +lonnavmaps provides functions and objects for dealing with the +compiled course hashes generated when a user enters the course, the +Apache handler for the "Navigation Map" button, and a flexible +prepared renderer for navigation maps that are easy to use anywhere. + +=head1 Object: navmap + +Encapsulating the compiled nav map + +navmap is an object that encapsulates a compiled course map and +provides a reasonable interface to it. + +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. + +You must obtain resource objects through the navmap object. + +=head2 Methods + +=over 4 + +=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. + +=cut + +use strict; use GDBM_File; -# -------------------------------------------------------------- Module Globals -my %hash; -my @rows; +sub new { + # magic invocation to create a class instance + my $proto = shift; + my $class = ref($proto) || $proto; + 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 + # them on-demand so we don't pay for creating resources unless we use them. + $self->{RESOURCE_CACHE} = {}; + + # Network failure flag, if we accessed the course or user opt and + # failed + $self->{NETWORK_FAILURE} = 0; + + # tie the nav hash + + my %navmaphash; + my %parmhash; + if (!(tie(%navmaphash, 'GDBM_File', $self->{NAV_HASH_FILE}, + &GDBM_READER(), 0640))) { + return undef; + } + + if (!(tie(%parmhash, 'GDBM_File', $self->{PARM_HASH_FILE}, + &GDBM_READER(), 0640))) + { + untie %{$self->{PARM_HASH}}; + return undef; + } -# -# These cache hashes need to be independent of user, resource and course -# (user and course can/should be in the keys) -# + # try copying into memory + my %tmpnavhash; + while (my ($k, $v) = each(%navmaphash)) { + $tmpnavhash{$k} = $v; + } + untie %navmaphash; -my %courserdatas; -my %userrdatas; + $self->{NAV_HASH} = \%tmpnavhash; + $self->{PARM_HASH} = \%parmhash; + $self->{INITED} = 0; -# -# These global hashes are dependent on user, course and resource, -# and need to be initialized every time when a sheet is calculated -# -my %courseopt; -my %useropt; -my %parmhash; + bless($self); + + return $self; +} +sub init { + my $self = shift; + if ($self->{INITED}) { return; } + + # If the course opt hash and the user opt hash should be generated, + # generate them + if ($self->{GENERATE_COURSE_USER_OPT}) { + my $uname=$ENV{'user.name'}; + my $udom=$ENV{'user.domain'}; + my $uhome=$ENV{'user.home'}; + my $cid=$ENV{'request.course.id'}; + my $chome=$ENV{'course.'.$cid.'.home'}; + my ($cdom,$cnum)=split(/\_/,$cid); + + my $userprefix=$uname.'_'.$udom.'_'; + + my %courserdatas; my %useropt; my %courseopt; my %userrdatas; + unless ($uhome eq 'no_host') { +# ------------------------------------------------- Get coursedata (if present) + unless ((time-$courserdatas{$cid.'.last_cache'})<240) { + my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum. + ':resourcedata',$chome); + # Check for network failure + if ( $reply =~ /no.such.host/i || $reply =~ /con_lost/i) { + $self->{NETWORK_FAILURE} = 1; + } elsif ($reply!~/^error\:/) { + $courserdatas{$cid}=$reply; + $courserdatas{$cid.'.last_cache'}=time; + } + } + foreach (split(/\&/,$courserdatas{$cid})) { + my ($name,$value)=split(/\=/,$_); + $courseopt{$userprefix.&Apache::lonnet::unescape($name)}= + &Apache::lonnet::unescape($value); + } +# --------------------------------------------------- Get userdata (if present) + unless ((time-$userrdatas{$uname.'___'.$udom.'.last_cache'})<240) { + my $reply=&Apache::lonnet::reply('dump:'.$udom.':'.$uname.':resourcedata',$uhome); + if ($reply!~/^error\:/) { + $userrdatas{$uname.'___'.$udom}=$reply; + $userrdatas{$uname.'___'.$udom.'.last_cache'}=time; + } + # check to see if network failed + elsif ( $reply=~/no.such.host/i || $reply=~/con.*lost/i ) + { + $self->{NETWORK_FAILURE} = 1; + } + } + foreach (split(/\&/,$userrdatas{$uname.'___'.$udom})) { + my ($name,$value)=split(/\=/,$_); + $useropt{$userprefix.&Apache::lonnet::unescape($name)}= + &Apache::lonnet::unescape($value); + } + $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}=''; + } + + if (($status{$msgid} eq 'new') || + (!$status{$msgid})) { + if ($what eq 'Error') { + $error{$url}.=','.$msgid; + } else { + $feedback{$url}.=','.$msgid; + } + } + } + } + + $self->{FEEDBACK} = \%feedback; + $self->{ERROR_MSG} = \%error; # what is this? JB + $self->{DISCUSSION_TIME} = \%discussiontime; + $self->{EMAIL_STATUS} = \%emailstatus; + + } + + $self->{PARM_CACHE} = {}; + $self->{INITED} = 1; +} -# ------------------------------------------------------------------ Euclid gcd +# 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}; +} + +# Checks to see if coursemap is defined, matching test in old lonnavmaps +sub courseMapDefined { + my $self = shift; + my $uri = &Apache::lonnet::clutter($ENV{'request.course.uri'}); + + my $firstres = $self->navhash("map_start_$uri"); + my $lastres = $self->navhash("map_finish_$uri"); + return $firstres && $lastres; +} -sub euclid { - my ($e,$f)=@_; - my $a; my $b; my $r; - if ($e>$f) { $b=$e; $r=$f; } else { $r=$e; $b=$f; } - while ($r!=0) { - $a=$b; $b=$r; - $r=$a%$b; +sub getIterator { + my $self = shift; + my $iterator = Apache::lonnavmaps::iterator->new($self, shift, shift, + shift, undef, shift); + return $iterator; +} + +# unties the hash when done +sub untieHashes { + my $self = shift; + untie %{$self->{NAV_HASH}}; + untie %{$self->{PARM_HASH}}; +} + +# Private method: 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 defined($self->{DISCUSSION_TIME}->{$symb}); + return $self->{DISCUSSION_TIME}->{$symb} > + $self->{LAST_CHECK}; +} + +# Private method: 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}; +} + +# Private method: Get the errors for that resource (by source). +sub getErrors { + my $self = shift; + my $src = shift; + + if (!defined($self->{ERROR_MSG})) { return ""; } + return $self->{ERROR_MSG}->{$src}; +} + +=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. + +=item * B(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(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 + +# 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 +# hash then we have to, which should hopefully alleviate speed problems. +# Caching is just an incidental detail I throw in because it makes sense. + +sub getById { + my $self = shift; + my $id = shift; + + if (defined ($self->{RESOURCE_CACHE}->{$id})) + { + return $self->{RESOURCE_CACHE}->{$id}; } - return $b; + + # resource handles inserting itself into cache. + # Not clear why the quotes are necessary, but as of this + # writing it doesn't work without them. + return "Apache::lonnavmaps::resource"->new($self, $id); +} + +sub getBySymb { + my $self = shift; + my $symb = shift; + my ($mapUrl, $id, $filename) = split (/___/, $symb); + my $map = $self->getResourceByUrl($mapUrl); + return $self->getById($map->map_pc() . '.' . $id); } -# --------------------------------------------------------------------- Parmval +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); +} -# -------------------------------------------- Figure out a cascading parameter -# -# For this function to work -# -# * parmhash needs to be tied -# * courseopt and useropt need to be initialized for this user and course -# +=pod + +=item * B(): + +Returns a resource object reference corresponding to the first +resource in the navmap. +=cut + +sub firstResource { + my $self = shift; + my $firstResource = $self->navhash('map_start_' . + &Apache::lonnet::clutter($ENV{'request.course.uri'})); + return $self->getById($firstResource); +} + +=pod + +=item * B(): + +Returns a resource object reference corresponding to the last resource +in the navmap. + +=cut + +sub finishResource { + my $self = shift; + my $firstResource = $self->navhash('map_finish_' . + &Apache::lonnet::clutter($ENV{'request.course.uri'})); + return $self->getById($firstResource); +} + +# Parmval reads the parm hash and cascades the lookups. parmval_real does +# the actual lookup; parmval caches the results. 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'}; @@ -76,475 +1899,1969 @@ sub parmval { my ($mapname,$id,$fn)=split(/\_\_\_/,$symb); # ----------------------------------------------------- Cascading lookup scheme - my $rwhat=$what; - $what=~s/^parameter\_//; - $what=~s/\_/\./; - - my $symbparm=$symb.'.'.$what; - my $mapparm=$mapname.'___(all).'.$what; - my $usercourseprefix=$uname.'_'.$udom.'_'.$cid; - - my $seclevel= - $usercourseprefix.'.['. - $csec.'].'.$what; - my $seclevelr= - $usercourseprefix.'.['. - $csec.'].'.$symbparm; - my $seclevelm= - $usercourseprefix.'.['. - $csec.'].'.$mapparm; - - my $courselevel= - $usercourseprefix.'.'.$what; - my $courselevelr= - $usercourseprefix.'.'.$symbparm; - my $courselevelm= - $usercourseprefix.'.'.$mapparm; - -# ---------------------------------------------------------- fourth, check user - - if ($uname) { - - if ($useropt{$courselevelr}) { return $useropt{$courselevelr}; } - - if ($useropt{$courselevelm}) { return $useropt{$courselevelm}; } - - if ($useropt{$courselevel}) { return $useropt{$courselevel}; } - - } - -# --------------------------------------------------------- third, check course - - if ($csec) { - - if ($courseopt{$seclevelr}) { return $courseopt{$seclevelr}; } - - if ($courseopt{$seclevelm}) { return $courseopt{$seclevelm}; } - - if ($courseopt{$seclevel}) { return $courseopt{$seclevel}; } - - } - - if ($courseopt{$courselevelr}) { return $courseopt{$courselevelr}; } - - if ($courseopt{$courselevelm}) { return $courseopt{$courselevelm}; } - - if ($courseopt{$courselevel}) { return $courseopt{$courselevel}; } - -# ----------------------------------------------------- second, check map parms - - my $thisparm=$parmhash{$symbparm}; - if ($thisparm) { return $thisparm; } - -# -------------------------------------------------------- first, check default - - return &Apache::lonnet::metadata($fn,$rwhat.'.default'); + my $rwhat=$what; + $what=~s/^parameter\_//; + $what=~s/\_/\./; + + my $symbparm=$symb.'.'.$what; + my $mapparm=$mapname.'___(all).'.$what; + my $usercourseprefix=$uname.'_'.$udom.'_'.$cid; + + my $seclevel= $usercourseprefix.'.['.$csec.'].'.$what; + my $seclevelr=$usercourseprefix.'.['.$csec.'].'.$symbparm; + my $seclevelm=$usercourseprefix.'.['.$csec.'].'.$mapparm; + + my $courselevel= $usercourseprefix.'.'.$what; + my $courselevelr=$usercourseprefix.'.'.$symbparm; + my $courselevelm=$usercourseprefix.'.'.$mapparm; + + my $useropt = $self->{USER_OPT}; + my $courseopt = $self->{COURSE_OPT}; + my $parmhash = $self->{PARM_HASH}; + +# ---------------------------------------------------------- first, check user + if ($uname and defined($useropt)) { + if (defined($$useropt{$courselevelr})) { return $$useropt{$courselevelr}; } + if (defined($$useropt{$courselevelm})) { return $$useropt{$courselevelm}; } + if (defined($$useropt{$courselevel})) { return $$useropt{$courselevel}; } + } + +# ------------------------------------------------------- second, check course + if ($csec and defined($courseopt)) { + if (defined($$courseopt{$seclevelr})) { return $$courseopt{$seclevelr}; } + if (defined($$courseopt{$seclevelm})) { return $$courseopt{$seclevelm}; } + if (defined($$courseopt{$seclevel})) { return $$courseopt{$seclevel}; } + } + + if (defined($courseopt)) { + if (defined($$courseopt{$courselevelr})) { return $$courseopt{$courselevelr}; } + if (defined($$courseopt{$courselevelm})) { return $$courseopt{$courselevelm}; } + if (defined($$courseopt{$courselevel})) { return $$courseopt{$courselevel}; } + } + +# ----------------------------------------------------- third, check map parms + + my $thisparm=$$parmhash{$symbparm}; + if (defined($thisparm)) { return $thisparm; } + +# ----------------------------------------------------- fourth , check default + + my $default=&Apache::lonnet::metadata($fn,$rwhat.'.default'); + if (defined($default)) { return $default} + +# --------------------------------------------------- fifth , cascade up parts + + my ($space,@qualifier)=split(/\./,$rwhat); + my $qualifier=join('.',@qualifier); + unless ($space eq '0') { + my @parts=split(/_/,$space); + my $id=pop(@parts); + my $part=join('_',@parts); + if ($part eq '') { $part='0'; } + my $partgeneral=$self->parmval($part.".$qualifier",$symb); + if (defined($partgeneral)) { return $partgeneral; } + } + return ''; +} + +=pod + +=item * B(url): + +Retrieves a resource object by URL of the resource. If passed a +resource object, it will simply return it, so it is safe to use this +method in code like "$res = $navmap->getResourceByUrl($res)", if +you're not sure if $res is already an object, or just a URL. If the +resource appears multiple times in the course, only the first instance +will be returned. As a result, this is probably useful only for maps. + +=item * B(map, filterFunc, recursive, bailout): + +The map is a specification of a map to retreive the resources from, +either as a url or as an object. The filterFunc is a reference to a +function that takes a resource object as its one argument and returns +true if the resource should be included, or false if it should not +be. If recursive is true, the map will be recursively examined, +otherwise it will not be. If bailout is true, the function will return +as soon as it finds a resource, if false it will finish. By default, +the map is the top-level map of the course, filterFunc is a function +that always returns 1, recursive is true, bailout is false. The +resources will be returned in a list containing the resource objects +for the corresponding resources, with B in +the list; regardless of branching, recursion, etc., it will be a flat +list. + +Thus, this is suitable for cases where you don't want the structure, +just a list of all resources. It is also suitable for finding out how +many resources match a given description; for this use, if all you +want to know is if I resources match the description, the bailout +parameter will allow you to avoid potentially expensive enumeration of +all matching resources. + +=item * B(map, filterFunc, recursive): + +Convience method for + + scalar(retrieveResources($map, $filterFunc, $recursive, 1)) > 0 + +which will tell whether the map has resources matching the description +in the filter function. + +=cut + +sub getResourceByUrl { + my $self = shift; + my $resUrl = shift; + + if (ref($resUrl)) { return $resUrl; } + + $resUrl = &Apache::lonnet::clutter($resUrl); + my $resId = $self->{NAV_HASH}->{'ids_' . $resUrl}; + if ($resId =~ /,/) { + $resId = (split (/,/, $resId))[0]; + } + if (!$resId) { return ''; } + return $self->getById($resId); +} + +sub retrieveResources { + my $self = shift; + my $map = shift; + my $filterFunc = shift; + if (!defined ($filterFunc)) { + $filterFunc = sub {return 1;}; + } + my $recursive = shift; + if (!defined($recursive)) { $recursive = 1; } + my $bailout = shift; + if (!defined($bailout)) { $bailout = 0; } + + # Create the necessary iterator. + if (!ref($map)) { # assume it's a url of a map. + $map = $self->getResourceByUrl($map); + } + + # Check the map's validity. + if (!$map || !$map->is_map()) { + # Oh, to throw an exception.... how I'd love that! + return (); + } + + # Get an iterator. + my $it = $self->getIterator($map->map_start(), $map->map_finish(), + !$recursive); + + my @resources = (); + + # Run down the iterator and collect the resources. + my $depth = 1; + $it->next(); + my $curRes = $it->next(); + + while ($depth > 0) { + if ($curRes == $it->BEGIN_MAP()) { + $depth++; + } + if ($curRes == $it->END_MAP()) { + $depth--; + } + if (ref($curRes)) { + if (!&$filterFunc($curRes)) { + next; + } + + push @resources, $curRes; + + if ($bailout) { + return @resources; + } + } + + $curRes = $it->next(); + } + + return @resources; } +sub hasResource { + my $self = shift; + my $map = shift; + my $filterFunc = shift; + my $recursive = shift; + + return scalar($self->retrieveResources($map, $filterFunc, $recursive, 1)) > 0; +} +1; -# ------------------------------------------------------------- Find out status - -sub astatus { - my $rid=shift; - my $code=1; - my $ctext=''; - $rid=~/(\d+)\.(\d+)/; - my $symb=&Apache::lonnet::declutter($hash{'map_id_'.$1}).'___'.$2.'___'. - &Apache::lonnet::declutter($hash{'src_'.$rid}); - my $duedate=&parmval('0.duedate',$symb); - my $opendate=&parmval('0.opendate',$symb); - my $answerdate=&parmval('0.answerdate',$symb); - my $now=time; - my $tcode=0; - if ($opendate) { - if ($now<$duedate) { - $tcode=2; - $ctext='Due: '.localtime($duedate); - if ($now<$opendate) { - $tcode=1; - $ctext='Open: '.localtime($opendate); - } - if ($duedate-$now<86400) { - $tcode=4; - $ctext='Due: '.localtime($duedate); - } - } else { - $tcode=3; - if ($now<$answerdate) { - $ctext='Answer: '.localtime($duedate); - } - } - } else { - $tcode=1; - } - my $answer=&Apache::lonnet::reply( - "restore:$ENV{'user.domain'}:$ENV{'user.name'}:". - $ENV{'request.course.id'}.':'. - &Apache::lonnet::escape($symb), - "$ENV{'user.home'}"); - my %returnhash=(); - map { - my ($name,$value)=split(/\=/,$_); - $returnhash{&Apache::lonnet::unescape($name)}= - &Apache::lonnet::unescape($value); - } split(/\&/,$answer); - if ($returnhash{'version'}) { - my $version; - for ($version=1;$version<=$returnhash{'version'};$version++) { - map { - $returnhash{$_}=$returnhash{$version.':'.$_}; - } split(/\:/,$returnhash{$version.':keys'}); - } - map { - if (($_=~/\.(\w+)\.solved$/) && ($_!~/^\d+\:/)) { - my $part=$1; - if ($ctext) { $ctext.=', '; } - if ($part) { - $ctext.='Part '.$part.': '; - } - if ($returnhash{$_} eq 'correct_by_student') { - unless ($code==2) { $code=3; } - $ctext.='solved'; - } elsif ($returnhash{$_} eq 'correct_by_override') { - unless ($code==2) { $code=3; } - $ctext.='override'; - } elsif ($returnhash{$_} eq 'incorrect_attempted') { - $code=2; - $ctext.= - $returnhash{'resource.'.$part.'.tries'}.'/'. - &parmval($part.'.maxtries',$symb).' tries'; - } elsif ($returnhash{$_} eq 'incorrect_by_override') { - $code=2; - $ctext.='override'; - } elsif ($returnhash{$_} eq 'excused') { - unless ($code==2) { $code=3; } - $ctext.='excused'; - } - } - } keys %returnhash; - } - return 'p'.$code.$tcode.'"'.$ctext.'"'; -} - -# ------------------------------------------------------------ Build page table - -sub tracetable { - my ($sofar,$rid,$beenhere)=@_; - my $further=$sofar; - unless ($beenhere=~/\&$rid\&/) { - $beenhere.=$rid.'&'; - - if (defined($hash{'is_map_'.$rid})) { - $sofar++; - my $tprefix=''; - if ($hash{'map_type_'.$hash{'map_pc_'.$hash{'src_'.$rid}}} - eq 'sequence') { - $tprefix='h'; - } - if (defined($rows[$sofar])) { - $rows[$sofar].='&'.$tprefix.$rid; - } else { - $rows[$sofar]=$tprefix.$rid; - } - if ((defined($hash{'map_start_'.$hash{'src_'.$rid}})) && - (defined($hash{'map_finish_'.$hash{'src_'.$rid}})) && - ($tprefix eq 'h')) { - my $frid=$hash{'map_finish_'.$hash{'src_'.$rid}}; - $sofar= - &tracetable($sofar,$hash{'map_start_'.$hash{'src_'.$rid}}, - '&'.$frid.'&'); - $sofar++; - if ($hash{'src_'.$frid}) { - my $brepriv=&Apache::lonnet::allowed('bre',$hash{'src_'.$frid}); - if (($brepriv eq '2') || ($brepriv eq 'F')) { - my $pprefix=''; - if ($hash{'src_'.$frid}=~ - /\.(problem|exam|quiz|assess|survey|form)$/) { - $pprefix=&astatus($frid); - - } - if (defined($rows[$sofar])) { - $rows[$sofar].='&'.$pprefix.$frid; - } else { - $rows[$sofar]=$pprefix.$frid; - } - } - } - } - } else { - $sofar++; - if ($hash{'src_'.$rid}) { - my $brepriv=&Apache::lonnet::allowed('bre',$hash{'src_'.$rid}); - if (($brepriv eq '2') || ($brepriv eq 'F')) { - my $pprefix=''; - if ($hash{'src_'.$rid}=~ - /\.(problem|exam|quiz|assess|survey|form)$/) { - $pprefix=&astatus($rid); - } - if (defined($rows[$sofar])) { - $rows[$sofar].='&'.$pprefix.$rid; - } else { - $rows[$sofar]=$pprefix.$rid; - } - } - } - } - - if (defined($hash{'to_'.$rid})) { - my $mincond=1; - my $next=''; - map { - my $thiscond= - &Apache::lonnet::directcondval($hash{'condid_'.$hash{'undercond_'.$_}}); - if ($thiscond>=$mincond) { - if ($next) { - $next.=','.$_.':'.$thiscond; - } else { - $next=$_.':'.$thiscond; - } - if ($thiscond>$mincond) { $mincond=$thiscond; } - } - } split(/\,/,$hash{'to_'.$rid}); - map { - my ($linkid,$condval)=split(/\:/,$_); - if ($condval>=$mincond) { - my $now=&tracetable($sofar,$hash{'goesto_'.$linkid},$beenhere); - if ($now>$further) { $further=$now; } - } - } split(/\,/,$next); +package Apache::lonnavmaps::iterator; + +=pod + +=back + +=head1 Object: navmap Iterator + +An I 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() function of a +B object. (Do not instantiate Apache::lonnavmaps::iterator +directly.) This will return a reference to the iterator: + +CgetIterator();> + +To get the next thing from the iterator, call B: + +Cnext()> + +getIterator behaves as follows: + +=over 4 + +=item * B(firstResource, finishResource, filterHash, condition, forceTop, returnTopMap): + +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. 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 + +=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_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 + +=cut + +# Here are the tokens for the iterator: + +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 +sub END_BRANCH { return 4; } # end of a branch +sub FORWARD { return 1; } # go forward +sub BACKWARD { return 2; } + +sub min { + (my $a, my $b) = @_; + if ($a < $b) { return $a; } else { return $b; } +} + +# In the CVS repository, documentation of this algorithm is included +# in /doc/lonnavdocs, as a PDF and .tex source. Markers like **1** +# will reference the same location in the text as the part of the +# algorithm is running through. + +sub new { + # magic invocation to create a class instance + my $proto = shift; + my $class = ref($proto) || $proto; + my $self = {}; + + $self->{NAV_MAP} = shift; + return undef unless ($self->{NAV_MAP}); + + # Handle the parameters + $self->{FIRST_RESOURCE} = shift || $self->{NAV_MAP}->firstResource(); + $self->{FINISH_RESOURCE} = shift || $self->{NAV_MAP}->finishResource(); + + # If the given resources are just the ID of the resource, get the + # objects + if (!ref($self->{FIRST_RESOURCE})) { $self->{FIRST_RESOURCE} = + $self->{NAV_MAP}->getById($self->{FIRST_RESOURCE}); } + if (!ref($self->{FINISH_RESOURCE})) { $self->{FINISH_RESOURCE} = + $self->{NAV_MAP}->getById($self->{FINISH_RESOURCE}); } + + $self->{FILTER} = shift; + + # A hash, used as a set, of resource already seen + $self->{ALREADY_SEEN} = shift; + if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} }; + $self->{CONDITION} = shift; + + # Do we want to automatically follow "redirection" maps? + $self->{FORCE_TOP} = shift; + + # Do we want to return the top-level map object (resource 0.0)? + $self->{RETURN_0} = shift; + # have we done that yet? + $self->{HAVE_RETURNED_0} = 0; + + # Now, we need to pre-process the map, by walking forward and backward + # over the parts of the map we're going to look at. + + # The processing steps are exactly the same, except for a few small + # changes, so I bundle those up in the following list of two elements: + # (direction_to_iterate, VAL_name, next_resource_method_to_call, + # first_resource). + # This prevents writing nearly-identical code twice. + my @iterations = ( [FORWARD(), 'TOP_DOWN_VAL', 'getNext', + 'FIRST_RESOURCE'], + [BACKWARD(), 'BOT_UP_VAL', 'getPrevious', + 'FINISH_RESOURCE'] ); + + my $maxDepth = 0; # tracks max depth + + # If there is only one resource in this map, and it's a map, we + # want to remember that, so the user can ask for the first map + # that isn't just a redirector. + my $resource; my $resourceCount = 0; + + # **1** + + foreach my $pass (@iterations) { + my $direction = $pass->[0]; + my $valName = $pass->[1]; + my $nextResourceMethod = $pass->[2]; + my $firstResourceName = $pass->[3]; + + my $iterator = Apache::lonnavmaps::DFSiterator->new($self->{NAV_MAP}, + $self->{FIRST_RESOURCE}, + $self->{FINISH_RESOURCE}, + {}, undef, 0, $direction); + + # prime the recursion + $self->{$firstResourceName}->{DATA}->{$valName} = 0; + my $depth = 0; + $iterator->next(); + my $curRes = $iterator->next(); + while ($depth > -1) { + if ($curRes == $iterator->BEGIN_MAP()) { $depth++; } + if ($curRes == $iterator->END_MAP()) { $depth--; } + + if (ref($curRes)) { + # If there's only one resource, this will save it + # we have to filter empty resources from consideration here, + # or even "empty", redirecting maps have two (start & finish) + # or three (start, finish, plus redirector) + if($direction == FORWARD && $curRes->src()) { + $resource = $curRes; $resourceCount++; + } + my $resultingVal = $curRes->{DATA}->{$valName}; + my $nextResources = $curRes->$nextResourceMethod(); + my $nextCount = scalar(@{$nextResources}); + + if ($nextCount == 1) { # **3** + my $current = $nextResources->[0]->{DATA}->{$valName} || 999999999; + $nextResources->[0]->{DATA}->{$valName} = min($resultingVal, $current); + } + + if ($nextCount > 1) { # **4** + foreach my $res (@{$nextResources}) { + my $current = $res->{DATA}->{$valName} || 999999999; + $res->{DATA}->{$valName} = min($current, $resultingVal + 1); + } + } + } + + # Assign the final val (**2**) + if (ref($curRes) && $direction == BACKWARD()) { + my $finalDepth = min($curRes->{DATA}->{TOP_DOWN_VAL}, + $curRes->{DATA}->{BOT_UP_VAL}); + + $curRes->{DATA}->{DISPLAY_DEPTH} = $finalDepth; + if ($finalDepth > $maxDepth) {$maxDepth = $finalDepth;} + } + } continue { + $curRes = $iterator->next(); + } + } + + # Check: Was this only one resource, a map? + if ($resourceCount == 1 && $resource->is_map() && !$self->{FORCE_TOP}) { + my $firstResource = $resource->map_start(); + my $finishResource = $resource->map_finish(); + return + Apache::lonnavmaps::iterator->new($self->{NAV_MAP}, $firstResource, + $finishResource, $self->{FILTER}, + $self->{ALREADY_SEEN}, + $self->{CONDITION}, 0); + + } + + # Set up some bookkeeping information. + $self->{CURRENT_DEPTH} = 0; + $self->{MAX_DEPTH} = $maxDepth; + $self->{STACK} = []; + $self->{RECURSIVE_ITERATOR_FLAG} = 0; - } + for (my $i = 0; $i <= $self->{MAX_DEPTH}; $i++) { + push @{$self->{STACK}}, []; } - return $further; + + # Prime the recursion w/ the first resource **5** + push @{$self->{STACK}->[0]}, $self->{FIRST_RESOURCE}; + $self->{ALREADY_SEEN}->{$self->{FIRST_RESOURCE}->{ID}} = 1; + + bless ($self); + + return $self; } -# ================================================================ Main Handler +sub next { + my $self = shift; -sub handler { - my $r=shift; + # If we want to return the top-level map object, and haven't yet, + # do so. + if ($self->{RETURN_0} && !$self->{HAVE_RETURNED_0}) { + $self->{HAVE_RETURNED_0} = 1; + return $self->{NAV_MAP}->getById('0.0'); + } + if ($self->{RECURSIVE_ITERATOR_FLAG}) { + # grab the next from the recursive iterator + my $next = $self->{RECURSIVE_ITERATOR}->next(); + + # is it a begin or end map? If so, update the depth + if ($next == BEGIN_MAP() ) { $self->{RECURSIVE_DEPTH}++; } + if ($next == END_MAP() ) { $self->{RECURSIVE_DEPTH}--; } + + # Are we back at depth 0? If so, stop recursing + if ($self->{RECURSIVE_DEPTH} == 0) { + $self->{RECURSIVE_ITERATOR_FLAG} = 0; + } -# ------------------------------------------- Set document type for header only + return $next; + } - if ($r->header_only) { - if ($ENV{'browser.mathml'}) { - $r->content_type('text/xml'); - } else { - $r->content_type('text/html'); - } - $r->send_http_header; - return OK; - } - - my $requrl=$r->uri; -# ----------------------------------------------------------------- Tie db file - if ($ENV{'request.course.fn'}) { - my $fn=$ENV{'request.course.fn'}; - if (-e "$fn.db") { - if ((tie(%hash,'GDBM_File',"$fn.db",&GDBM_READER,0640)) && - (tie(%parmhash,'GDBM_File', - $ENV{'request.course.fn'}.'_parms.db',&GDBM_READER,0640))) { -# ------------------------------------------------------------------- Hash tied - my $firstres=$hash{'map_start_/res/'.$ENV{'request.course.uri'}}; - my $lastres=$hash{'map_finish_/res/'.$ENV{'request.course.uri'}}; - if (($firstres) && ($lastres)) { -# ----------------------------------------------------------------- Render page -# -------------------------------------------------------------- Set parameters - - -# ---------------------------- initialize coursedata and userdata for this user - undef %courseopt; - undef %useropt; + if (defined($self->{FORCE_NEXT})) { + my $tmp = $self->{FORCE_NEXT}; + $self->{FORCE_NEXT} = undef; + return $tmp; + } - my $uname=$ENV{'user.name'}; - my $udom=$ENV{'user.domain'}; - my $uhome=$ENV{'user.home'}; - my $cid=$ENV{'request.course.id'}; - my $chome=$ENV{'course.'.$cid.'.home'}; - my ($cdom,$cnum)=split(/\_/,$cid); + # Have we not yet begun? If not, return BEGIN_MAP and + # remember we've started. + if ( !$self->{STARTED} ) { + $self->{STARTED} = 1; + return $self->BEGIN_MAP(); + } - my $userprefix=$uname.'_'.$udom.'_'; + # Here's the guts of the iterator. + + # Find the next resource, if any. + my $found = 0; + my $i = $self->{MAX_DEPTH}; + my $newDepth; + my $here; + while ( $i >= 0 && !$found ) { + if ( scalar(@{$self->{STACK}->[$i]}) > 0 ) { # **6** + $here = pop @{$self->{STACK}->[$i]}; # **7** + $found = 1; + $newDepth = $i; + } + $i--; + } - unless ($uhome eq 'no_host') { -# -------------------------------------------------------------- Get coursedata - unless - ((time-$courserdatas{$cid.'.last_cache'})<240) { - my $reply=&Apache::lonnet::reply('dump:'.$cdom.':'.$cnum. - ':resourcedata',$chome); - if ($reply!~/^error\:/) { - $courserdatas{$cid}=$reply; - $courserdatas{$cid.'.last_cache'}=time; - } - } - map { - my ($name,$value)=split(/\=/,$_); - $courseopt{$userprefix.&Apache::lonnet::unescape($name)}= - &Apache::lonnet::unescape($value); - } split(/\&/,$courserdatas{$cid}); -# --------------------------------------------------- Get userdata (if present) - unless - ((time-$userrdatas{$uname.'___'.$udom.'.last_cache'})<240) { - my $reply= - &Apache::lonnet::reply('dump:'.$udom.':'.$uname.':resourcedata',$uhome); - if ($reply!~/^error\:/) { - $userrdatas{$uname.'___'.$udom}=$reply; - $userrdatas{$uname.'___'.$udom.'.last_cache'}=time; - } - } - map { - my ($name,$value)=split(/\=/,$_); - $useropt{$userprefix.&Apache::lonnet::unescape($name)}= - &Apache::lonnet::unescape($value); - } split(/\&/,$userrdatas{$uname.'___'.$udom}); - } - - @rows=(); - - &tracetable(0,$firstres,'&'.$lastres.'&'); - if ($hash{'src_'.$lastres}) { - my $brepriv= - &Apache::lonnet::allowed('bre',$hash{'src_'.$lastres}); - if (($brepriv eq '2') || ($brepriv eq 'F')) { - $rows[$#rows+1]=''.$lastres; - } - } - -# ------------------------------------------------------------------ Page parms - - my $j; - my $i; - my $lcm=1; - my $contents=0; - -# ---------------------------------------------- Go through table to get layout - - for ($i=0;$i<=$#rows;$i++) { - if ($rows[$i]) { - $contents++; - my @colcont=split(/\&/,$rows[$i]); - $lcm*=($#colcont+1)/euclid($lcm,($#colcont+1)); - } - } + # If we still didn't find anything, we're done. + if ( !$found ) { + # We need to get back down to the correct branch depth + if ( $self->{CURRENT_DEPTH} > 0 ) { + $self->{CURRENT_DEPTH}--; + return END_BRANCH(); + } else { + return END_MAP(); + } + } + + # If this is not a resource, it must be an END_BRANCH marker we want + # to return directly. + if (!ref($here)) { # **8** + if ($here == END_BRANCH()) { # paranoia, in case of later extension + $self->{CURRENT_DEPTH}--; + return $here; + } + } + + # Otherwise, it is a resource and it's safe to store in $self->{HERE} + $self->{HERE} = $here; + + # Get to the right level + if ( $self->{CURRENT_DEPTH} > $newDepth ) { + push @{$self->{STACK}->[$newDepth]}, $here; + $self->{CURRENT_DEPTH}--; + return END_BRANCH(); + } + if ( $self->{CURRENT_DEPTH} < $newDepth) { + push @{$self->{STACK}->[$newDepth]}, $here; + $self->{CURRENT_DEPTH}++; + return BEGIN_BRANCH(); + } + + # If we made it here, we have the next resource, and we're at the + # right branch level. So let's examine the resource for where + # we can get to from here. + + # So we need to look at all the resources we can get to from here, + # categorize them if we haven't seen them, remember if we have a new + my $nextUnfiltered = $here->getNext(); + my $maxDepthAdded = -1; + + for (@$nextUnfiltered) { + if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) { + my $depth = $_->{DATA}->{DISPLAY_DEPTH}; + push @{$self->{STACK}->[$depth]}, $_; + $self->{ALREADY_SEEN}->{$_->{ID}} = 1; + if ($maxDepthAdded < $depth) { $maxDepthAdded = $depth; } + } + } + # Is this the end of a branch? If so, all of the resources examined above + # led to lower levels then the one we are currently at, so we push a END_BRANCH + # marker onto the stack so we don't forget. + # Example: For the usual A(BC)(DE)F case, when the iterator goes down the + # BC branch and gets to C, it will see F as the only next resource, but it's + # one level lower. Thus, this is the end of the branch, since there are no + # more resources added to this level or above. + # We don't do this if the examined resource is the finish resource, + # because the condition given above is true, but the "END_MAP" will + # take care of things and we should already be at depth 0. + my $isEndOfBranch = $maxDepthAdded < $self->{CURRENT_DEPTH}; + if ($isEndOfBranch && $here != $self->{FINISH_RESOURCE}) { # **9** + push @{$self->{STACK}->[$self->{CURRENT_DEPTH}]}, END_BRANCH(); + } + + # That ends the main iterator logic. Now, do we want to recurse + # down this map (if this resource is a map)? + if ($self->{HERE}->is_map() && + (defined($self->{FILTER}->{$self->{HERE}->map_pc()}) xor $self->{CONDITION})) { + $self->{RECURSIVE_ITERATOR_FLAG} = 1; + my $firstResource = $self->{HERE}->map_start(); + my $finishResource = $self->{HERE}->map_finish(); + + $self->{RECURSIVE_ITERATOR} = + Apache::lonnavmaps::iterator->new($self->{NAV_MAP}, $firstResource, + $finishResource, $self->{FILTER}, + $self->{ALREADY_SEEN}, $self->{CONDITION}); + } + + # If this is a blank resource, don't actually return it. + # Should you ever find you need it, make sure to add an option to the code + # that you can use; other things depend on this behavior. + my $browsePriv = $self->{HERE}->browsePriv(); + if (!$self->{HERE}->src() || + (!($browsePriv eq 'F') && !($browsePriv eq '2')) ) { + return $self->next(); + } - unless ($contents) { - $r->content_type('text/html'); - $r->send_http_header; - $r->print('Empty Map.'); - } else { - -# ------------------------------------------------------------------ Build page - -# ---------------------------------------------------------------- Send headers - - $r->content_type('text/html'); - $r->send_http_header; - $r->print( - 'Navigate LON-CAPA Maps'); - - $r->print(''. - ''. - ''. - '

Navigate Course Map

'); - $r->rflush(); -# ----------------------------------------------------------------- Start table - $r->print(''); - for ($i=0;$i<=$#rows;$i++) { - if ($rows[$i]) { - $r->print("\n"); - my @colcont=split(/\&/,$rows[$i]); - my $avespan=$lcm/($#colcont+1); - for ($j=0;$j<=$#colcont;$j++) { - my $rid=$colcont[$j]; - my $add=''; - my $hwk=''; - my $hwke=''; - if ($rid=~/^h(.+)/) { - $rid=$1; - $add=''; - } - if ($rid=~/^p(\d)(\d)\"([\w\: \(\)\/\,]*)\"(.+)/) { - my $code=$1; - my $tcode=$2; - my $ctext=$3; - $rid=$4; - if ($tcode eq '1') { - $add=''; - } - } - $hwk=''; - $hwke=''; - if ($code eq '1') { - $hwke=' ('.$ctext.')'; - } - if ($code eq '2') { - $hwk=''; - $hwke=' ('.$ctext.')'; - } - if ($code eq '3') { - $hwk=''; - $hwke=' ('.$ctext.')'; - } - } - $r->print($add.''.$hwk. - $hash{'title_'.$rid}.$hwke.''.$adde); - } - $r->print(''); - } - } - $r->print("\n
  '; - my $adde=''; - $adde=''; - } - if ($code eq '3') { - $add=''; - } else { - $add=''; - if ($tcode eq '2') { - $add=''; - } - if ($tcode eq '4') { - $add=''; - $adde='
"); - - $r->print(''); -# -------------------------------------------------------------------- End page - } -# ------------------------------------------------------------- End render page - } else { - $r->content_type('text/html'); - $r->send_http_header; - $r->print('Coursemap undefined.'); - } -# ------------------------------------------------------------------ Untie hash - unless (untie(%hash)) { - &Apache::lonnet::logthis("WARNING: ". - "Could not untie coursemap $fn (browse)."); - } - unless (untie(%parmhash)) { - &Apache::lonnet::logthis("WARNING: ". - "Could not untie parmhash (browse)."); - } -# -------------------------------------------------------------------- All done - return OK; -# ----------------------------------------------- Errors, hash could no be tied - } - } - } + return $self->{HERE}; - $ENV{'user.error.msg'}="$requrl:bre:0:0:Course not initialized"; - return HTTP_NOT_ACCEPTABLE; +} + +=pod + +The other method available on the iterator is B, which +returns an array populated with the current 'stack' of maps, as +references to the resource objects. Example: This is useful when +making the navigation map, as we need to check whether we are under a +page map to see if we need to link directly to the resource, or to the +page. The first elements in the array will correspond to the top of +the stack (most inclusive map). + +=cut + +sub getStack { + my $self=shift; + + my @stack; + + $self->populateStack(\@stack); + + return \@stack; +} + +# Private method: Calls the iterators recursively to populate the stack. +sub populateStack { + my $self=shift; + my $stack = shift; + + push @$stack, $self->{HERE} if ($self->{HERE}); + + if ($self->{RECURSIVE_ITERATOR_FLAG}) { + $self->{RECURSIVE_ITERATOR}->populateStack($stack); + } } 1; -__END__ +package Apache::lonnavmaps::DFSiterator; + +# Not documented in the perldoc: This is a simple iterator that just walks +# through the nav map and presents the resources in a depth-first search +# fashion, ignorant of conditionals, randomized resources, etc. It presents +# BEGIN_MAP and END_MAP, but does not understand branches at all. It is +# useful for pre-processing of some kind, and is in fact used by the main +# iterator that way, but that's about it. +# One could imagine merging this into the init routine of the main iterator, +# but this might as well be left seperate, since it is possible some other +# use might be found for it. - Jeremy + +# Unlike the main iterator, this DOES return all resources, even blank ones. +# The main iterator needs them to correctly preprocess the map. + +sub BEGIN_MAP { return 1; } # begining of a new map +sub END_MAP { return 2; } # end of the map +sub FORWARD { return 1; } # go forward +sub BACKWARD { return 2; } + +# Params: Nav map ref, first resource id/ref, finish resource id/ref, +# filter hash ref (or undef), already seen hash or undef, condition +# (as in main iterator), direction FORWARD or BACKWARD (undef->forward). +sub new { + # magic invocation to create a class instance + my $proto = shift; + my $class = ref($proto) || $proto; + my $self = {}; + + $self->{NAV_MAP} = shift; + return undef unless ($self->{NAV_MAP}); + + $self->{FIRST_RESOURCE} = shift || $self->{NAV_MAP}->firstResource(); + $self->{FINISH_RESOURCE} = shift || $self->{NAV_MAP}->finishResource(); + + # If the given resources are just the ID of the resource, get the + # objects + if (!ref($self->{FIRST_RESOURCE})) { $self->{FIRST_RESOURCE} = + $self->{NAV_MAP}->getById($self->{FIRST_RESOURCE}); } + if (!ref($self->{FINISH_RESOURCE})) { $self->{FINISH_RESOURCE} = + $self->{NAV_MAP}->getById($self->{FINISH_RESOURCE}); } + + $self->{FILTER} = shift; + + # A hash, used as a set, of resource already seen + $self->{ALREADY_SEEN} = shift; + if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} }; + $self->{CONDITION} = shift; + $self->{DIRECTION} = shift || FORWARD(); + + # Flag: Have we started yet? + $self->{STARTED} = 0; + + # Should we continue calling the recursive iterator, if any? + $self->{RECURSIVE_ITERATOR_FLAG} = 0; + # The recursive iterator, if any + $self->{RECURSIVE_ITERATOR} = undef; + # Are we recursing on a map, or a branch? + $self->{RECURSIVE_MAP} = 1; # we'll manually unset this when recursing on branches + # And the count of how deep it is, so that this iterator can keep track of + # when to pick back up again. + $self->{RECURSIVE_DEPTH} = 0; + + # For keeping track of our branches, we maintain our own stack + $self->{STACK} = []; + + # Start with the first resource + if ($self->{DIRECTION} == FORWARD) { + push @{$self->{STACK}}, $self->{FIRST_RESOURCE}; + } else { + push @{$self->{STACK}}, $self->{FINISH_RESOURCE}; + } + + bless($self); + return $self; +} + +sub next { + my $self = shift; + + # Are we using a recursive iterator? If so, pull from that and + # watch the depth; we want to resume our level at the correct time. + if ($self->{RECURSIVE_ITERATOR_FLAG}) { + # grab the next from the recursive iterator + my $next = $self->{RECURSIVE_ITERATOR}->next(); + + # is it a begin or end map? Update depth if so + if ($next == BEGIN_MAP() ) { $self->{RECURSIVE_DEPTH}++; } + if ($next == END_MAP() ) { $self->{RECURSIVE_DEPTH}--; } + + # Are we back at depth 0? If so, stop recursing. + if ($self->{RECURSIVE_DEPTH} == 0) { + $self->{RECURSIVE_ITERATOR_FLAG} = 0; + } + + return $next; + } + + # Is there a current resource to grab? If not, then return + # END_MAP, which will end the iterator. + if (scalar(@{$self->{STACK}}) == 0) { + return $self->END_MAP(); + } + + # Have we not yet begun? If not, return BEGIN_MAP and + # remember that we've started. + if ( !$self->{STARTED} ) { + $self->{STARTED} = 1; + return $self->BEGIN_MAP; + } + + # Get the next resource in the branch + $self->{HERE} = pop @{$self->{STACK}}; + + # remember that we've seen this, so we don't return it again later + $self->{ALREADY_SEEN}->{$self->{HERE}->{ID}} = 1; + + # Get the next possible resources + my $nextUnfiltered; + if ($self->{DIRECTION} == FORWARD()) { + $nextUnfiltered = $self->{HERE}->getNext(); + } else { + $nextUnfiltered = $self->{HERE}->getPrevious(); + } + my $next = []; + + # filter the next possibilities to remove things we've + # already seen. + foreach (@$nextUnfiltered) { + if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) { + push @$next, $_; + } + } + + while (@$next) { + # copy the next possibilities over to the stack + push @{$self->{STACK}}, shift @$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()}) xor $self->{CONDITION})) { + $self->{RECURSIVE_ITERATOR_FLAG} = 1; + my $firstResource = $self->{HERE}->map_start(); + my $finishResource = $self->{HERE}->map_finish(); + + $self->{RECURSIVE_ITERATOR} = + Apache::lonnavmaps::DFSiterator->new ($self->{NAV_MAP}, $firstResource, + $finishResource, $self->{FILTER}, $self->{ALREADY_SEEN}, + $self->{CONDITION}, $self->{DIRECTION}); + } + + return $self->{HERE}; +} + +# 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. + +sub getStack { + my $self=shift; + + my @stack; + + $self->populateStack(\@stack); + + return \@stack; +} + +# Private method: Calls the iterators recursively to populate the stack. +sub populateStack { + my $self=shift; + my $stack = shift; + + push @$stack, $self->{HERE} if ($self->{HERE}); + + if ($self->{RECURSIVE_ITERATOR_FLAG}) { + $self->{RECURSIVE_ITERATOR}->populateStack($stack); + } +} + +1; + +package Apache::lonnavmaps::resource; + +use Apache::lonnet; + +=pod + +=head1 Object: resource + +A resource object encapsulates a resource in a resource map, allowing +easy manipulation of the resource, querying the properties of the +resource (including user properties), and represents a reference that +can be used as the canonical representation of the resource by +lonnavmap clients like renderers. + +A resource only makes sense in the context of a navmap, as some of the +data is stored in the navmap object. + +You will probably never need to instantiate this object directly. Use +Apache::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 Public Members + +resource objects have a hash called DATA ($resourceRef->{DATA}) that +you can store whatever you want in. This allows you to easily do +two-pass algorithms without worrying about managing your own +resource->data hash. + +=head2 Methods + +=over 4 + +=item * B($navmapRef, $idString): + +The first arg is a reference to the parent navmap object. The second +is the idString of the resource itself. Very rarely, if ever, called +directly. Use the nav map->getByID() method. + +=back + +=cut + +sub new { + # magic invocation to create a class instance + my $proto = shift; + my $class = ref($proto) || $proto; + my $self = {}; + + $self->{NAV_MAP} = shift; + $self->{ID} = shift; + + # 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 + # directly. + $self->{DATA} = {}; + + bless($self); + + return $self; +} + +# private function: simplify the NAV_HASH lookups we keep doing +# pass the name, and to automatically append my ID, pass a true val on the +# second param +sub navHash { + my $self = shift; + my $param = shift; + my $id = shift; + return $self->{NAV_MAP}->navhash($param . ($id?$self->{ID}:"")); +} + +=pod + +B + +These are methods that help you retrieve metadata about the resource: +Method names are based on the fields in the compiled course +representation. + +=over 4 + +=item * B: + +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: + +Returns true if the resource is external. + +=item * B: + +Returns the "goesto" value from the compiled nav map. (It is likely +you want to use B instead.) + +=item * B: + +Returns the kind of the resource from the compiled nav map. + +=item * B: + +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: + +Returns true for a map if the randompick feature is being used on the +map. (?) + +=item * B: + +Returns the source for the resource. + +=item * B: + +Returns the symb for the resource. + +=item * B: + +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 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); } +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); +} +sub symb { + my $self=shift; + (my $first, my $second) = $self->{ID} =~ /(\d+).(\d+)/; + my $symbSrc = &Apache::lonnet::declutter($self->src()); + return &Apache::lonnet::declutter( + $self->navHash('map_id_'.$first)) + . '___' . $second . '___' . $symbSrc; +} +sub title { my $self=shift; return $self->navHash("title_", 1); } +sub to { my $self=shift; return $self->navHash("to_", 1); } +sub compTitle { + my $self = shift; + my $title = $self->title(); + $title=~s/\&colon\;/\:/gs; + if (!$title) { + $title = $self->src(); + $title = substr($title, rindex($title, '/') + 1); + } + return $title; +} +=pod + +B<Predicate Testing the Resource> + +These methods are shortcuts to deciding if a given resource has a given property. + +=over 4 + +=item * B<is_map>: + +Returns true if the resource is a map type. + +=item * B<is_problem>: + +Returns true if the resource is a problem type, false +otherwise. (Looks at the extension on the src field; might need more +to work correctly.) + +=item * B<is_page>: + +Returns true if the resource is a page. + +=item * B<is_sequence>: + +Returns true if the resource is a sequence. + +=back + +=cut + + +sub is_html { + my $self=shift; + my $src = $self->src(); + return ($src =~ /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 =~ /page$/); +} +sub is_problem { + my $self=shift; + my $src = $self->src(); + return ($src =~ /problem$/); +} +sub is_sequence { + my $self=shift; + my $src = $self->src(); + return ($src =~ /sequence$/); +} + +# Private method: Shells out to the parmval in the nav map, handler parts. +sub parmval { + my $self = shift; + my $what = shift; + my $part = shift; + if (!defined($part)) { + $part = '0'; + } + return $self->{NAV_MAP}->parmval($part.'.'.$what, $self->symb()); +} + +=pod + +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 map_finish { + my $self = shift; + my $src = $self->src(); + $src = Apache::lonnet::clutter($src); + my $res = $self->navHash("map_finish_$src", 0); + $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(); + $src = Apache::lonnet::clutter($src); + my $res = $self->navHash("map_start_$src", 0); + $res = $self->{NAV_MAP}->getById($res); + return $res; +} +sub map_type { + my $self = shift; + my $pc = $self->map_pc(); + return $self->navHash("map_type_$pc", 0); +} + + + +##### +# Property queries +##### + +# These functions will be responsible for returning the CORRECT +# VALUE for the parameter, no matter what. So while they may look +# like direct calls to parmval, they can be more then that. +# So, for instance, the duedate function should use the "duedatetype" +# information, rather then the resource object user. + +=pod + +=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. + +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 + +=item * B<acc>: + +Get the Client IP/Name Access Control information. + +=item * B<answerdate>: + +Get the answer-reveal date for the problem. + +=item * B<duedate>: + +Get the due date for the problem. + +=item * B<tries>: + +Get the number of tries the student has used on the problem. + +=item * B<maxtries>: + +Get the number of max tries allowed. + +=item * B<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 + +=cut + +sub acc { + (my $self, my $part) = @_; + return $self->parmval("acc", $part); +} +sub answerdate { + (my $self, my $part) = @_; + # Handle intervals + if ($self->parmval("answerdate.type", $part) eq 'date_interval') { + return $self->duedate($part) + + $self->parmval("answerdate", $part); + } + return $self->parmval("answerdate", $part); +} +sub awarded { my $self = shift; return $self->queryRestoreHash('awarded', shift); } +sub duedate { + (my $self, my $part) = @_; + return $self->parmval("duedate", $part); +} +sub maxtries { + (my $self, my $part) = @_; + return $self->parmval("maxtries", $part); +} +sub opendate { + (my $self, my $part) = @_; + if ($self->parmval("opendate.type", $part) eq 'date_interval') { + return $self->duedate($part) - + $self->parmval("opendate", $part); + } + return $self->parmval("opendate"); +} +sub problemstatus { + (my $self, my $part) = @_; + return $self->parmval("problemstatus", $part); +} +sub sig { + (my $self, my $part) = @_; + return $self->parmval("sig", $part); +} +sub tol { + (my $self, my $part) = @_; + return $self->parmval("tol", $part); +} +sub tries { + my $self = shift; + my $tries = $self->queryRestoreHash('tries', shift); + if (!defined($tries)) { return '0';} + return $tries; +} +sub type { + (my $self, my $part) = @_; + return $self->parmval("type", $part); +} +sub weight { + my $self = shift; my $part = shift; + 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()); + $self->{RETURN_HASH} = \%tmpHash; + } +} +###### +# Status queries +###### +# These methods query the status of problems. +# If we need to count parts, this function determines the number of +# parts from the metadata. When called, it returns a reference to a list +# of strings corresponding to the parts. (Thus, using it in a scalar context +# tells you how many parts you have in the problem: +# $partcount = scalar($resource->countParts()); +# Don't use $self->{PARTS} directly because you don't know if it's been +# computed yet. +=pod + +=head2 Resource misc + +Misc. functions for the resource. + +=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<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; + my $source = $self->src(); + if ($source =~ /^\/res\//) { $source = substr $source, 5; } + return $self->{NAV_MAP}->getFeedback($source); +} + +sub getErrors { + my $self = shift; + my $source = $self->src(); + if ($source =~ /^\/res\//) { $source = substr $source, 5; } + return $self->{NAV_MAP}->getErrors($source); +} + +=pod + +=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<multipart>(): + +Returns true if the problem is multipart, false otherwise. Use this instead +of countParts if all you want is multipart/not multipart. + +=item * B<responseType>($part): + +Returns the response type of the part, without the word "response" on the +end. Example return values: 'string', 'essay', 'numeric', etc. + +=item * B<responseIds>($part): + +Retreives the response IDs for the given part as an array reference containing +strings naming the response IDs. This may be empty. + +=back + +=cut + +sub parts { + my $self = shift; + + if ($self->ext) { return []; } + + $self->extractParts(); + return $self->{PARTS}; +} + +sub countParts { + my $self = shift; + + 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}) { + return 0; + } + + return scalar(@{$parts}); # + $delta; +} + +sub multipart { + my $self = shift; + return $self->countParts() > 1; +} + +sub responseType { + my $self = shift; + my $part = shift; + + $self->extractParts(); + return $self->{RESPONSE_TYPE}->{$part}; +} + +sub responseIds { + my $self = shift; + my $part = shift; + + $self->extractParts(); + return $self->{RESPONSE_IDS}->{$part}; +} + +# Private function: Extracts the parts information, both part names and +# part types, and saves it. +sub extractParts { + my $self = shift; + + return if (defined($self->{PARTS})); + return if ($self->ext); + + $self->{PARTS} = []; + + my %parts; + + # Retrieve part count, if this is a problem + if ($self->is_problem()) { + my $metadata = &Apache::lonnet::metadata($self->src(), 'packages'); + if (!$metadata) { + $self->{RESOURCE_ERROR} = 1; + $self->{PARTS} = []; + $self->{PART_TYPE} = {}; + return; + } + foreach (split(/\,/,$metadata)) { + if ($_ =~ /^part_(.*)$/) { + my $part = $1; + # This floods the logs if it blows up + if (defined($parts{$part})) { + Apache::lonnet::logthis("$part multiply defined in metadata for " . $self->symb()); + } + + # check to see if part is turned off. + + if (!Apache::loncommon::check_if_partid_hidden($part, $self->symb())) { + $parts{$part} = 1; + } + } + } + + + my @sortedParts = sort keys %parts; + $self->{PARTS} = \@sortedParts; + + my %responseIdHash; + my %responseTypeHash; + + + # Init the responseIdHash + foreach (@{$self->{PARTS}}) { + $responseIdHash{$_} = []; + } + + # Now, the unfortunate thing about this is that parts, part name, and + # response if are delimited by underscores, but both the part + # name and response id can themselves have underscores in them. + # So we have to use our knowlege of part names to figure out + # where the part names begin and end, and even then, it is possible + # to construct ambiguous situations. + foreach (split /,/, $metadata) { + if ($_ =~ /^([a-zA-Z]+)response_(.*)/) { + my $responseType = $1; + my $partStuff = $2; + my $partIdSoFar = ''; + my @partChunks = split /_/, $partStuff; + my $i = 0; + + for ($i = 0; $i < scalar(@partChunks); $i++) { + if ($partIdSoFar) { $partIdSoFar .= '_'; } + $partIdSoFar .= $partChunks[$i]; + if ($parts{$partIdSoFar}) { + my @otherChunks = @partChunks[$i+1..$#partChunks]; + my $responseId = join('_', @otherChunks); + push @{$responseIdHash{$partIdSoFar}}, $responseId; + $responseTypeHash{$partIdSoFar} = $responseType; + last; + } + } + } + } + + $self->{RESPONSE_IDS} = \%responseIdHash; + $self->{RESPONSE_TYPES} = \%responseTypeHash; + } + + return; +} + +=pod + +=head2 Resource Status + +Problem resources have status information, reflecting their various +dates and completion statuses. + +There are two aspects to the status: the date-related information and +the completion information. + +Idiomatic usage of these two methods would probably look something +like + + foreach ($resource->parts()) { + my $dateStatus = $resource->getDateStatus($_); + my $completionStatus = $resource->getCompletionStatus($_); + + or + + my $status = $resource->status($_); + + ... use it here ... + } + +Which you use depends on exactly what you are looking for. The +status() function has been optimized for the nav maps display and may +not precisely match what you need elsewhere. + +The symbolic constants shown below can be accessed through the +resource object: C<$res->OPEN>. + +=over 4 + +=item * B<getDateStatus>($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 + +B<Date Codes> + +=over 4 + +=item * B<OPEN_LATER>: + +The problem will be opened later. + +=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. + +=item * B<ANSWER_OPEN>: + +The answer date is here. + +=item * B<NETWORK_FAILURE>: + +The information is unknown due to network failure. + +=back + +=cut + +# Apparently the compiler optimizes these into constants automatically +sub OPEN_LATER { return 0; } +sub OPEN { return 1; } +sub PAST_DUE_NO_ANSWER { return 2; } +sub PAST_DUE_ANSWER_LATER { return 3; } +sub ANSWER_OPEN { return 4; } +sub NOTHING_SET { return 5; } +sub NETWORK_FAILURE { return 100; } + +# getDateStatus gets the date status for a given problem part. +# Because answer date, due date, and open date are fully independent +# (i.e., it is perfectly possible to *only* have an answer date), +# we have to completely cover the 3x3 maxtrix of (answer, due, open) x +# (past, future, none given). This function handles this with a decision +# tree. Read the comments to follow the decision tree. + +sub getDateStatus { + my $self = shift; + my $part = shift; + $part = "0" if (!defined($part)); + + # Always return network failure if there was one. + return $self->NETWORK_FAILURE if ($self->{NAV_MAP}->{NETWORK_FAILURE}); + + my $now = time(); + + my $open = $self->opendate($part); + my $due = $self->duedate($part); + my $answer = $self->answerdate($part); + + if (!$open && !$due && !$answer) { + # no data on the problem at all + # 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 $self->ANSWER_OPEN; } + return PAST_DUE_NO_ANSWER; +} + +=pod + +B<> + +=over 4 + +=item * B<getCompletionStatus>($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: + +=back + +B<Completion Codes> + +=over 4 + +=item * B<NOT_ATTEMPTED>: + +Has not been attempted at all. + +=item * B<INCORRECT>: + +Attempted, but wrong by student. + +=item * B<INCORRECT_BY_OVERRIDE>: + +Attempted, but wrong by instructor override. + +=item * B<CORRECT>: + +Correct or correct by instructor. + +=item * B<CORRECT_BY_OVERRIDE>: + +Correct by instructor override. + +=item * B<EXCUSED>: + +Excused. Not yet implemented. + +=item * B<NETWORK_FAILURE>: + +Information not available due to network failure. + +=item * B<ATTEMPTED>: + +Attempted, and not yet graded. + +=back + +=cut + +sub NOT_ATTEMPTED { return 10; } +sub INCORRECT { return 11; } +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; + return $self->NETWORK_FAILURE if ($self->{NAV_MAP}->{NETWORK_FAILURE}); + + my $status = $self->queryRestoreHash('solved', shift); + + # Left as seperate if statements in case we ever do more with this + if ($status eq 'correct_by_student') {return $self->CORRECT;} + if ($status eq 'correct_by_override') {return $self->CORRECT_BY_OVERRIDE; } + if ($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; +} + +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.'.'.$hashentry}; +} + +=pod + +B<Composite Status> + +Along with directly returning the date or completion status, the +resource object includes a convenience function B<status>() that will +combine the two status tidbits into one composite status that can +represent the status of the resource as a whole. This method represents +the concept of the thing we want to display to the user on the nav maps +screen, which is a combination of completion and open status. The precise logic is +documented in the comments of the status method. The following results +may be returned, all available as methods on the resource object +($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 + +=item * B<NETWORK_FAILURE>: + +The network has failed and the information is not available. + +=item * B<NOTHING_SET>: + +No dates have been set for this problem (part) at all. (Because only +certain parts of a multi-part problem may be assigned, this can not be +collapsed into "open later", as we do not know a given part will EVER +be opened. For single part, this is the same as "OPEN_LATER".) + +=item * B<CORRECT>: + +For any reason at all, the part is considered correct. + +=item * B<EXCUSED>: + +For any reason at all, the problem is excused. + +=item * B<PAST_DUE_NO_ANSWER>: + +The problem is past due, not considered correct, and no answer date is +set. + +=item * B<PAST_DUE_ANSWER_LATER>: + +The problem is past due, not considered correct, and an answer date in +the future is set. + +=item * B<ANSWER_OPEN>: + +The problem is past due, not correct, and the answer is now available. + +=item * B<OPEN_LATER>: + +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<INCORRECT>: + +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 + +=cut + +sub TRIES_LEFT { return 20; } +sub ANSWER_SUBMITTED { return 21; } + +sub status { + my $self = shift; + my $part = shift; + if (!defined($part)) { $part = "0"; } + my $completionStatus = $self->getCompletionStatus($part); + my $dateStatus = $self->getDateStatus($part); + + # What we have is a two-dimensional matrix with 4 entries on one + # dimension and 5 entries on the other, which we want to colorize, + # plus network failure and "no date data at all". + + if ($completionStatus == NETWORK_FAILURE) { return NETWORK_FAILURE; } + + my $suppressFeedback = lc($self->parmval("problemstatus", $part)) eq 'no'; + + # There are a few whole rows we can dispose of: + if ($completionStatus == CORRECT || + $completionStatus == CORRECT_BY_OVERRIDE ) { + return $suppressFeedback? ANSWER_SUBMITTED : CORRECT; + } + + if ($completionStatus == ATTEMPTED) { + return ATTEMPTED; + } + + # If it's EXCUSED, then return that no matter what + if ($completionStatus == EXCUSED) { + return EXCUSED; + } + + if ($dateStatus == NOTHING_SET) { + return NOTHING_SET; + } + + # 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 ) { + return $dateStatus; + } + + if ($dateStatus == ANSWER_OPEN) { + return ANSWER_OPEN; + } + + # Now: (incorrect, incorrect_override, not_attempted) x + # (open_later), (open) + + if ($dateStatus == OPEN_LATER) { + return OPEN_LATER; + } + + # If it's WRONG... + if ($completionStatus == INCORRECT || $completionStatus == INCORRECT_BY_OVERRIDE) { + # and there are TRIES LEFT: + if ($self->tries($part) < $self->maxtries($part) || !$self->maxtries($part)) { + return TRIES_LEFT; + } + return $suppressFeedback ? ANSWER_SUBMITTED : INCORRECT; # otherwise, return orange; student can't fix this + } + + # Otherwise, it's untried and open + return OPEN; +} + +=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 (!(($status == OPEN() || $status == TRIES_LEFT()) + && $self->getCompletionStatus($part) != ATTEMPTED() + && $status != ANSWER_SUBMITTED())) { + return 0; + } + } + + # If all the parts were complete, so was this problem. + return 1; +} + +=pod + +=head2 Resource/Nav Map Navigation + +=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<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 + +sub getNext { + my $self = shift; + my @branches; + my $to = $self->to(); + foreach my $branch ( split(/,/, $to) ) { + my $choice = $self->{NAV_MAP}->getById($branch); + my $next = $choice->goesto(); + $next = $self->{NAV_MAP}->getById($next); + + push @branches, $next; + } + return \@branches; +} + +sub getPrevious { + my $self = shift; + my @branches; + my $from = $self->from(); + foreach my $branch ( split /,/, $from) { + my $choice = $self->{NAV_MAP}->getById($branch); + my $prev = $choice->comesfrom(); + $prev = $self->{NAV_MAP}->getById($prev); + + push @branches, $prev; + } + return \@branches; +} + +sub browsePriv { + my $self = shift; + if (defined($self->{BROWSE_PRIV})) { + return $self->{BROWSE_PRIV}; + } + + $self->{BROWSE_PRIV} = &Apache::lonnet::allowed('bre', $self->src()); +} + +=pod + +=back + +=cut + +1; + +__END__