File:  [LON-CAPA] / loncom / interface / lonnavmaps.pm
Revision 1.451: download - view: text, annotated - select for diffs
Wed Nov 17 22:46:27 2010 UTC (13 years, 6 months ago) by raeburn
Branches: MAIN
CVS tags: HEAD
- Bug 6396. Check NAV_HASH lookups in &navHash() are on an object.

    1: # The LearningOnline Network with CAPA
    2: # Navigate Maps Handler
    3: #
    4: # $Id: lonnavmaps.pm,v 1.451 2010/11/17 22:46:27 raeburn Exp $
    5: 
    6: #
    7: # Copyright Michigan State University Board of Trustees
    8: #
    9: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
   10: #
   11: # LON-CAPA is free software; you can redistribute it and/or modify
   12: # it under the terms of the GNU General Public License as published by
   13: # the Free Software Foundation; either version 2 of the License, or
   14: # (at your option) any later version.
   15: #
   16: # LON-CAPA is distributed in the hope that it will be useful,
   17: # but WITHOUT ANY WARRANTY; without even the implied warranty of
   18: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   19: # GNU General Public License for more details.
   20: #
   21: # You should have received a copy of the GNU General Public License
   22: # along with LON-CAPA; if not, write to the Free Software
   23: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   24: #
   25: # /home/httpd/html/adm/gpl.txt
   26: #
   27: # http://www.lon-capa.org/
   28: #
   29: ###
   30: 
   31: =pod
   32: 
   33: =head1 NAME
   34: 
   35: Apache::lonnavmaps - Subroutines to handle and render the navigation
   36: 
   37: =head1 SYNOPSIS
   38: 
   39: Handles navigational maps.
   40: 
   41: The main handler generates the navigational listing for the course,
   42: the other objects export this information in a usable fashion for
   43: other modules.
   44: 
   45: 
   46: This is part of the LearningOnline Network with CAPA project
   47: described at http://www.lon-capa.org.
   48: 
   49: 
   50: =head1 OVERVIEW
   51: 
   52: X<lonnavmaps, overview> When a user enters a course, LON-CAPA examines the
   53: course structure and caches it in what is often referred to as the
   54: "big hash" X<big hash>. You can see it if you are logged into
   55: LON-CAPA, in a course, by going to /adm/test. (You may need to
   56: tweak the /home/httpd/lonTabs/htpasswd file to view it.) The
   57: content of the hash will be under the heading "Big Hash".
   58: 
   59: Big Hash contains, among other things, how resources are related
   60: to each other (next/previous), what resources are maps, which 
   61: resources are being chosen to not show to the student (for random
   62: selection), and a lot of other things that can take a lot of time
   63: to compute due to the amount of data that needs to be collected and
   64: processed.
   65: 
   66: Apache::lonnavmaps provides an object model for manipulating this
   67: information in a higher-level fashion than directly manipulating 
   68: the hash. It also provides access to several auxilary functions 
   69: that aren't necessarily stored in the Big Hash, but are a per-
   70: resource sort of value, like whether there is any feedback on 
   71: a given resource.
   72: 
   73: Apache::lonnavmaps also abstracts away branching, and someday, 
   74: conditions, for the times where you don't really care about those
   75: things.
   76: 
   77: Apache::lonnavmaps also provides fairly powerful routines for
   78: rendering navmaps, and last but not least, provides the navmaps
   79: view for when the user clicks the NAV button.
   80: 
   81: B<Note>: Apache::lonnavmaps I<only> works for the "currently
   82: logged in user"; if you want things like "due dates for another
   83: student" lonnavmaps can not directly retrieve information like
   84: that. You need the EXT function. This module can still help,
   85: because many things, such as the course structure, are constant
   86: between users, and Apache::lonnavmaps can help by providing
   87: symbs for the EXT call.
   88: 
   89: The rest of this file will cover the provided rendering routines, 
   90: which can often be used without fiddling with the navmap object at
   91: all, then documents the Apache::lonnavmaps::navmap object, which
   92: is the key to accessing the Big Hash information, covers the use
   93: of the Iterator (which provides the logic for traversing the 
   94: somewhat-complicated Big Hash data structure), documents the
   95: Apache::lonnavmaps::Resource objects that are returned by 
   96: 
   97: =head1 Subroutine: render
   98: 
   99: The navmap renderer package provides a sophisticated rendering of the
  100: standard navigation maps interface into HTML. The provided nav map
  101: handler is actually just a glorified call to this.
  102: 
  103: Because of the large number of parameters this function accepts,
  104: instead of passing it arguments as is normal, pass it in an anonymous
  105: hash with the desired options.
  106: 
  107: The package provides a function called 'render', called as
  108: Apache::lonnavmaps::render({}).
  109: 
  110: =head2 Overview of Columns
  111: 
  112: The renderer will build an HTML table for the navmap and return
  113: it. The table consists of several columns, and a row for each
  114: resource (or possibly each part). You tell the renderer how many
  115: columns to create and what to place in each column, optionally using
  116: one or more of the prepared columns, and the renderer will assemble
  117: the table.
  118: 
  119: Any additional generally useful column types should be placed in the
  120: renderer code here, so anybody can use it anywhere else. Any code
  121: specific to the current application (such as the addition of <input>
  122: elements in a column) should be placed in the code of the thing using
  123: the renderer.
  124: 
  125: At the core of the renderer is the array reference COLS (see Example
  126: section below for how to pass this correctly). The COLS array will
  127: consist of entries of one of two types of things: Either an integer
  128: representing one of the pre-packaged column types, or a sub reference
  129: that takes a resource reference, a part number, and a reference to the
  130: argument hash passed to the renderer, and returns a string that will
  131: be inserted into the HTML representation as it.
  132: 
  133: All other parameters are ways of either changing how the columns
  134: are printing, or which rows are shown.
  135: 
  136: The pre-packaged column names are refered to by constants in the
  137: Apache::lonnavmaps namespace. The following currently exist:
  138: 
  139: =over 4
  140: 
  141: =item * B<Apache::lonnavmaps::resource>:
  142: 
  143: The general info about the resource: Link, icon for the type, etc. The
  144: first column in the standard nav map display. This column provides the
  145: indentation effect seen in the B<NAV> screen. This column also accepts
  146: the following parameters in the renderer hash:
  147: 
  148: =over 4
  149: 
  150: =item * B<resource_nolink>: default false
  151: 
  152: If true, the resource will not be linked. By default, all non-folder
  153: resources are linked.
  154: 
  155: =item * B<resource_part_count>: default true
  156: 
  157: If true, the resource will show a part count B<if> the full
  158: part list is not displayed. (See "condense_parts" later.) If false,
  159: the resource will never show a part count.
  160: 
  161: =item * B<resource_no_folder_link>:
  162: 
  163: If true, the resource's folder will not be clickable to open or close
  164: it. Default is false. True implies printCloseAll is false, since you
  165: can't close or open folders when this is on anyhow.
  166: 
  167: =back
  168: 
  169: =item * B<Apache::lonnavmaps::communication_status>:
  170: 
  171: Whether there is discussion on the resource, email for the user, or
  172: (lumped in here) perl errors in the execution of the problem. This is
  173: the second column in the main nav map.
  174: 
  175: =item * B<Apache::lonnavmaps::quick_status>:
  176: 
  177: An icon for the status of a problem, with five possible states:
  178: Correct, incorrect, open, awaiting grading (for a problem where the
  179: computer's grade is suppressed, or the computer can't grade, like
  180: essay problem), or none (not open yet, not a problem). The
  181: third column of the standard navmap.
  182: 
  183: =item * B<Apache::lonnavmaps::long_status>:
  184: 
  185: A text readout of the details of the current status of the problem,
  186: such as "Due in 22 hours". The fourth column of the standard navmap.
  187: 
  188: =item * B<Apache::lonnavmaps::part_status_summary>:
  189: 
  190: A text readout summarizing the status of the problem. If it is a
  191: single part problem, will display "Correct", "Incorrect", 
  192: "Not yet open", "Open", "Attempted", or "Error". If there are
  193: multiple parts, this will output a string that in HTML will show a
  194: status of how many parts are in each status, in color coding, trying
  195: to match the colors of the icons within reason.
  196: 
  197: Note this only makes sense if you are I<not> showing parts. If 
  198: C<showParts> is true (see below), this column will not output
  199: anything. 
  200: 
  201: =back
  202: 
  203: If you add any others please be sure to document them here.
  204: 
  205: An example of a column renderer that will show the ID number of a
  206: resource, along with the part name if any:
  207: 
  208:  sub { 
  209:   my ($resource, $part, $params) = @_;   
  210:   if ($part) { return '<td>' . $resource->{ID} . ' ' . $part . '</td>'; }
  211:   return '<td>' . $resource->{ID} . '</td>';
  212:  }
  213: 
  214: Note these functions are responsible for the TD tags, which allow them
  215: to override vertical and horizontal alignment, etc.
  216: 
  217: =head2 Parameters
  218: 
  219: Minimally, you should be
  220: able to get away with just using 'cols' (to specify the columns
  221: shown), 'url' (necessary for the folders to link to the current screen
  222: correctly), and possibly 'queryString' if your app calls for it. In
  223: that case, maintaining the state of the folders will be done
  224: automatically.
  225: 
  226: =over 4
  227: 
  228: =item * B<iterator>: default: constructs one from %env
  229: 
  230: A reference to a fresh ::iterator to use from the navmaps. The
  231: rendering will reflect the options passed to the iterator, so you can
  232: use that to just render a certain part of the course, if you like. If
  233: one is not passed, the renderer will attempt to construct one from
  234: env{'form.filter'} and env{'form.condition'} information, plus the
  235: 'iterator_map' parameter if any.
  236: 
  237: =item * B<iterator_map>: default: not used
  238: 
  239: If you are letting the renderer do the iterator handling, you can
  240: instruct the renderer to render only a particular map by passing it
  241: the source of the map you want to process, like
  242: '/res/103/jerf/navmap.course.sequence'.
  243: 
  244: =item * B<include_top_level_map>: default: false
  245: 
  246: If you need to include the top level map (meaning the course) in the
  247: rendered output set this to true
  248: 
  249: =item * B<navmap>: default: constructs one from %env
  250: 
  251: A reference to a navmap, used only if an iterator is not passed in. If
  252: this is necessary to make an iterator but it is not passed in, a new
  253: one will be constructed based on env info. This is useful to do basic
  254: error checking before passing it off to render.
  255: 
  256: =item * B<r>: default: must be passed in
  257: 
  258: The standard Apache response object. This must be passed to the
  259: renderer or the course hash will be locked.
  260: 
  261: =item * B<cols>: default: empty (useless)
  262: 
  263: An array reference
  264: 
  265: =item * B<showParts>:default true
  266: 
  267: A flag. If true, a line for the resource itself, and a line
  268: for each part will be displayed. If not, only one line for each
  269: resource will be displayed.
  270: 
  271: =item * B<condenseParts>: default true
  272: 
  273: A flag. If true, if all parts of the problem have the same
  274: status and that status is Nothing Set, Correct, or Network Failure,
  275: then only one line will be displayed for that resource anyhow. If no,
  276: all parts will always be displayed. If showParts is 0, this is
  277: ignored.
  278: 
  279: =item * B<jumpCount>: default: determined from %env
  280: 
  281: A string identifying the URL to place the anchor 'curloc' at.
  282: It is the responsibility of the renderer user to
  283: ensure that the #curloc is in the URL. By default, determined through
  284: the use of the env{} 'jump' information, and should normally "just
  285: work" correctly.
  286: 
  287: =item * B<here>: default: empty string
  288: 
  289: A Symb identifying where to place the 'here' marker. The empty
  290: string means no marker.
  291: 
  292: =item * B<indentString>: default: 25 pixel whitespace image
  293: 
  294: A string identifying the indentation string to use. 
  295: 
  296: =item * B<queryString>: default: empty
  297: 
  298: A string which will be prepended to the query string used when the
  299: folders are opened or closed. You can use this to pass
  300: application-specific values.
  301: 
  302: =item * B<url>: default: none
  303: 
  304: The url the folders will link to, which should be the current
  305: page. Required if the resource info column is shown, and you 
  306: are allowing the user to open and close folders.
  307: 
  308: =item * B<currentJumpIndex>: default: no jumping
  309: 
  310: Describes the currently-open row number to cause the browser to jump
  311: to, because the user just opened that folder. By default, pulled from
  312: the Jump information in the env{'form.*'}.
  313: 
  314: =item * B<printKey>: default: false
  315: 
  316: If true, print the key that appears on the top of the standard
  317: navmaps.
  318: 
  319: =item * B<printCloseAll>: default: true
  320: 
  321: If true, print the "Close all folders" or "open all folders"
  322: links.
  323: 
  324: =item * B<filterFunc>: default: sub {return 1;} (accept everything)
  325: 
  326: A function that takes the resource object as its only parameter and
  327: returns a true or false value. If true, the resource is displayed. If
  328: false, it is simply skipped in the display.
  329: 
  330: =item * B<suppressEmptySequences>: default: false
  331: 
  332: If you're using a filter function, and displaying sequences to orient
  333: the user, then frequently some sequences will be empty. Setting this to
  334: true will cause those sequences not to display, so as not to confuse the
  335: user into thinking that if the sequence is there there should be things
  336: under it; for example, see the "Show Uncompleted Homework" view on the
  337: B<NAV> screen.
  338: 
  339: =item * B<suppressNavmaps>: default: false
  340: 
  341: If true, will not display Navigate Content resources. 
  342: 
  343: =back
  344: 
  345: =head2 Additional Info
  346: 
  347: In addition to the parameters you can pass to the renderer, which will
  348: be passed through unchange to the column renderers, the renderer will
  349: generate the following information which your renderer may find
  350: useful:
  351: 
  352: =over 4
  353: 
  354: =item * B<counter>: 
  355: 
  356: Contains the number of rows printed. Useful after calling the render 
  357: function, as you can detect whether anything was printed at all.
  358: 
  359: =item * B<isNewBranch>:
  360: 
  361: Useful for renderers: If this resource is currently the first resource
  362: of a new branch, this will be true. The Resource column (leftmost in the
  363: navmaps screen) uses this to display the "new branch" icon 
  364: 
  365: =back
  366: 
  367: =cut
  368: 
  369: 
  370: =head1 SUBROUTINES
  371: 
  372: =over
  373: 
  374: =item update()
  375: 
  376: =item addToFilter()
  377: 
  378: Convenience functions: Returns a string that adds or subtracts
  379: the second argument from the first hash, appropriate for the 
  380: query string that determines which folders to recurse on
  381: 
  382: =item removeFromFilter()
  383: 
  384: =item getLinkForResource()
  385: 
  386: Convenience function: Given a stack returned from getStack on the iterator,
  387: return the correct src() value.
  388: 
  389: =item getDescription()
  390: 
  391: Convenience function: This separates the logic of how to create
  392: the problem text strings ("Due: DATE", "Open: DATE", "Not yet assigned",
  393: etc.) into a separate function. It takes a resource object as the
  394: first parameter, and the part number of the resource as the second.
  395: It's basically a big switch statement on the status of the resource.
  396: 
  397: =item dueInLessThan24Hours()
  398: 
  399: Convenience function, so others can use it: Is the problem due in less than 24 hours, and still can be done?
  400: 
  401: =item lastTry()
  402: 
  403: Convenience function, so others can use it: Is there only one try remaining for the
  404: part, with more than one try to begin with, not due yet and still can be done?
  405: 
  406: =item advancedUser()
  407: 
  408: This puts a human-readable name on the env variable.
  409: 
  410: =item timeToHumanString()
  411: 
  412: timeToHumanString takes a time number and converts it to a
  413: human-readable representation, meant to be used in the following
  414: manner:
  415: 
  416: =over 4
  417: 
  418: =item * print "Due $timestring"
  419: 
  420: =item * print "Open $timestring"
  421: 
  422: =item * print "Answer available $timestring"
  423: 
  424: =back
  425: 
  426: Very, very, very, VERY English-only... goodness help a localizer on
  427: this func...
  428: 
  429: =item resource()
  430: 
  431: returns 0
  432: 
  433: =item communication_status()
  434: 
  435: returns 1
  436: 
  437: =item quick_status()
  438: 
  439: returns 2
  440: 
  441: =item long_status()
  442: 
  443: returns 3
  444: 
  445: =item part_status_summary()
  446: 
  447: returns 4
  448: 
  449: =item render_resource()
  450: 
  451: =item render_communication_status()
  452: 
  453: =item render_quick_status()
  454: 
  455: =item render_long_status()
  456: 
  457: =item render_parts_summary_status()
  458: 
  459: =item setDefault()
  460: 
  461: =item cmp_title()
  462: 
  463: =item render()
  464: 
  465: =item add_linkitem()
  466: 
  467: =item show_linkitems()
  468: 
  469: =back
  470: 
  471: =cut
  472: 
  473: package Apache::lonnavmaps;
  474: 
  475: use strict;
  476: use GDBM_File;
  477: use Apache::loncommon();
  478: use Apache::lonenc();
  479: use Apache::lonlocal;
  480: use Apache::lonnet;
  481: 
  482: use POSIX qw (floor strftime);
  483: use Time::HiRes qw( gettimeofday tv_interval );
  484: use LONCAPA;
  485: use DateTime();
  486: 
  487: # symbolic constants
  488: sub SYMB { return 1; }
  489: sub URL { return 2; }
  490: sub NOTHING { return 3; }
  491: 
  492: # Some data
  493: 
  494: my $resObj = "Apache::lonnavmaps::resource";
  495: 
  496: # Keep these mappings in sync with lonquickgrades, which usesthe colors
  497: # instead of the icons.
  498: my %statusIconMap = 
  499:     (
  500:      $resObj->CLOSED       => '',
  501:      $resObj->OPEN         => 'navmap.open.gif',
  502:      $resObj->CORRECT      => 'navmap.correct.gif',
  503:      $resObj->PARTIALLY_CORRECT      => 'navmap.partial.gif',
  504:      $resObj->INCORRECT    => 'navmap.wrong.gif',
  505:      $resObj->ATTEMPTED    => 'navmap.ellipsis.gif',
  506:      $resObj->ERROR        => ''
  507:      );
  508: 
  509: my %iconAltTags =   #texthash does not work here
  510:     ( 'navmap.correct.gif'  => 'Correct',
  511:       'navmap.wrong.gif'    => 'Incorrect',
  512:       'navmap.open.gif'     => 'Open',
  513:       'navmap.partial.gif'  => 'Partially Correct',
  514:       'navmap.ellipsis.gif' => 'Attempted',
  515:      );
  516: 
  517: # Defines a status->color mapping, null string means don't color
  518: my %colormap = 
  519:     ( $resObj->NETWORK_FAILURE        => '',
  520:       $resObj->CORRECT                => '',
  521:       $resObj->EXCUSED                => '#3333FF',
  522:       $resObj->PAST_DUE_ANSWER_LATER  => '',
  523:       $resObj->PAST_DUE_NO_ANSWER     => '',
  524:       $resObj->ANSWER_OPEN            => '#006600',
  525:       $resObj->OPEN_LATER             => '',
  526:       $resObj->TRIES_LEFT             => '',
  527:       $resObj->INCORRECT              => '',
  528:       $resObj->OPEN                   => '',
  529:       $resObj->NOTHING_SET            => '',
  530:       $resObj->ATTEMPTED              => '',
  531:       $resObj->CREDIT_ATTEMPTED       => '',
  532:       $resObj->ANSWER_SUBMITTED       => '',
  533:       $resObj->PARTIALLY_CORRECT      => '#006600'
  534:       );
  535: # And a special case in the nav map; what to do when the assignment
  536: # is not yet done and due in less than 24 hours
  537: my $hurryUpColor = "#FF0000";
  538: 
  539: my $future_slots_checked = 0;
  540: my $future_slots = 0;
  541: 
  542: sub addToFilter {
  543:     my $hashIn = shift;
  544:     my $addition = shift;
  545:     my %hash = %$hashIn;
  546:     $hash{$addition} = 1;
  547: 
  548:     return join (",", keys(%hash));
  549: }
  550: 
  551: sub removeFromFilter {
  552:     my $hashIn = shift;
  553:     my $subtraction = shift;
  554:     my %hash = %$hashIn;
  555: 
  556:     delete $hash{$subtraction};
  557:     return join(",", keys(%hash));
  558: }
  559: 
  560: sub getLinkForResource {
  561:     my $stack = shift;
  562:     my $res;
  563: 
  564:     # Check to see if there are any pages in the stack
  565:     foreach $res (@$stack) {
  566:         if (defined($res)) {
  567: 	    my $anchor;
  568: 	    if ($res->is_page()) {
  569: 		foreach my $item (@$stack) { if (defined($item)) { $anchor = $item; }  }
  570: 		$anchor=&escape($anchor->shown_symb());
  571: 		return ($res->link(),$res->shown_symb(),$anchor);
  572: 	    }
  573:             # in case folder was skipped over as "only sequence"
  574: 	    my ($map,$id,$src)=&Apache::lonnet::decode_symb($res->symb());
  575: 	    if ($map=~/\.page$/) {
  576: 		my $url=&Apache::lonnet::clutter($map);
  577: 		$anchor=&escape($res->shown_symb());
  578: 		return ($url,$res->shown_symb(),$anchor);
  579: 	    }
  580:         }
  581:     }
  582: 
  583:     # Failing that, return the src of the last resource that is defined
  584:     # (when we first recurse on a map, it puts an undefined resource
  585:     # on the bottom because $self->{HERE} isn't defined yet, and we
  586:     # want the src for the map anyhow)
  587:     foreach my $item (@$stack) {
  588:         if (defined($item)) { $res = $item; }
  589:     }
  590: 
  591:     if ($res) {
  592: 	return ($res->link(),$res->shown_symb());
  593:     }
  594:     return;
  595: }
  596: 
  597: 
  598: 
  599: sub getDescription {
  600:     my $res = shift;
  601:     my $part = shift;
  602:     my $status = $res->status($part);
  603: 
  604:     my $open = $res->opendate($part);
  605:     my $due = $res->duedate($part);
  606:     my $answer = $res->answerdate($part);
  607: 
  608:     if ($status == $res->NETWORK_FAILURE) { 
  609:         return &mt("Having technical difficulties; please check status later"); 
  610:     }
  611:     if ($status == $res->NOTHING_SET) {
  612:         return &mt("Not currently assigned.");
  613:     }
  614:     if ($status == $res->OPEN_LATER) {
  615:         return &mt("Open ") .timeToHumanString($open,'start');
  616:     }
  617:     if ($res->simpleStatus($part) == $res->OPEN) {
  618:         unless (&Apache::lonnet::allowed('mgr',$env{'request.course.id'})) {
  619:             my ($slot_status,$slot_time,$slot_name)=$res->check_for_slot($part);
  620:             if ($slot_status == $res->UNKNOWN) {
  621:                 return &mt('Reservation status unknown');
  622:             } elsif ($slot_status == $res->RESERVED) {
  623:                 return &mt('Reserved - ends [_1]',
  624:                            timeToHumanString($slot_time,'end'));
  625:             } elsif ($slot_status == $res->RESERVED_LOCATION) {
  626:                 return &mt('Reserved - specific location(s) - ends [_1]',
  627:                            timeToHumanString($slot_time,'end'));
  628:             } elsif ($slot_status == $res->RESERVED_LATER) {
  629:                 return &mt('Reserved - next open [_1]',
  630:                            timeToHumanString($slot_time,'start'));
  631:             } elsif ($slot_status == $res->RESERVABLE) {
  632:                 return &mt('Reservable ending [_1]',
  633:                            timeToHumanString($slot_time,'end'));
  634:             } elsif ($slot_status == $res->RESERVABLE_LATER) {
  635:                 return &mt('Reservable starting [_1]',
  636:                            timeToHumanString($slot_time,'start'));
  637:             } elsif ($slot_status == $res->NOT_IN_A_SLOT) {
  638:                 return &mt('Reserve a time/place to work');
  639:             } elsif ($slot_status == $res->NOTRESERVABLE) {
  640:                 return &mt('Reservation not available');
  641:             } elsif ($slot_status == $res->WAITING_FOR_GRADE) {
  642:                 return &mt('Submission in grading queue');
  643:             }
  644:         }
  645:     }
  646:     if ($status == $res->OPEN) {
  647:         if ($due) {
  648: 	    if ($res->is_practice()) {
  649: 		return &mt("Closes ")."  " .timeToHumanString($due,'start');
  650: 	    } else {
  651: 		return &mt("Due")."  " .timeToHumanString($due,'end');
  652: 	    }
  653:         } else {
  654:             return &mt("Open, no due date");
  655:         }
  656:     }
  657:     if ($status == $res->PAST_DUE_ANSWER_LATER) {
  658:         return &mt("Answer open")." " .timeToHumanString($answer,'start');
  659:     }
  660:     if ($status == $res->PAST_DUE_NO_ANSWER) {
  661: 	if ($res->is_practice()) {
  662: 	    return &mt("Closed")." " . timeToHumanString($due,'start');
  663: 	} else {
  664: 	    return &mt("Was due")." " . timeToHumanString($due,'end');
  665: 	}
  666:     }
  667:     if (($status == $res->ANSWER_OPEN || $status == $res->PARTIALLY_CORRECT)
  668: 	&& $res->handgrade($part) ne 'yes') {
  669:         return &mt("Answer available");
  670:     }
  671:     if ($status == $res->EXCUSED) {
  672:         return &mt("Excused by instructor");
  673:     }
  674:     if ($status == $res->ATTEMPTED) {
  675:         if ($res->is_anonsurvey($part) || $res->is_survey($part)) {
  676:             return &mt("Survey submission recorded");
  677:         } else {
  678:             return &mt("Answer submitted, not yet graded");
  679:         }
  680:     }
  681:     if ($status == $res->CREDIT_ATTEMPTED) {
  682:         if ($res->is_anonsurvey($part) || $res->is_survey($part)) {
  683:             return &mt("Credit for survey submission");
  684:         }
  685:     }
  686:     if ($status == $res->TRIES_LEFT) {
  687:         my $tries = $res->tries($part);
  688:         my $maxtries = $res->maxtries($part);
  689:         my $triesString = "";
  690:         if ($tries && $maxtries) {
  691:             $triesString = '<font size="-1"><i>('.&mt('[_1] of [quant,_2,try,tries] used',$tries,$maxtries).')</i></font>';
  692:             if ($maxtries > 1 && $maxtries - $tries == 1) {
  693:                 $triesString = "<b>$triesString</b>";
  694:             }
  695:         }
  696:         if ($due) {
  697:             return &mt("Due")." " . timeToHumanString($due,'end') .
  698:                 " $triesString";
  699:         } else {
  700:             return &mt("No due date")." $triesString";
  701:         }
  702:     }
  703:     if ($status == $res->ANSWER_SUBMITTED) {
  704:         return &mt('Answer submitted');
  705:     }
  706: }
  707: 
  708: 
  709: sub dueInLessThan24Hours {
  710:     my $res = shift;
  711:     my $part = shift;
  712:     my $status = $res->status($part);
  713: 
  714:     return ($status == $res->OPEN() ||
  715:             $status == $res->TRIES_LEFT()) &&
  716: 	    $res->duedate($part) && $res->duedate($part) < time()+(24*60*60) &&
  717: 	    $res->duedate($part) > time();
  718: }
  719: 
  720: 
  721: sub lastTry {
  722:     my $res = shift;
  723:     my $part = shift;
  724: 
  725:     my $tries = $res->tries($part);
  726:     my $maxtries = $res->maxtries($part);
  727:     return $tries && $maxtries && $maxtries > 1 &&
  728:         $maxtries - $tries == 1 && $res->duedate($part) &&
  729:         $res->duedate($part) > time();
  730: }
  731: 
  732: 
  733: sub advancedUser {
  734:     return $env{'request.role.adv'};
  735: }
  736: 
  737: sub timeToHumanString {
  738:     my ($time,$type,$format) = @_;
  739: 
  740:     # zero, '0' and blank are bad times
  741:     if (!$time) {
  742:         return &mt('never');
  743:     }
  744:     unless (&Apache::lonlocal::current_language()=~/^en/) {
  745: 	return &Apache::lonlocal::locallocaltime($time);
  746:     } 
  747:     my $now = time();
  748: 
  749:     # Positive = future
  750:     my $delta = $time - $now;
  751: 
  752:     my $minute = 60;
  753:     my $hour = 60 * $minute;
  754:     my $day = 24 * $hour;
  755:     my $week = 7 * $day;
  756:     my $inPast = 0;
  757: 
  758:     # Logic in comments:
  759:     # Is it now? (extremely unlikely)
  760:     if ( $delta == 0 ) {
  761:         return "this instant";
  762:     }
  763: 
  764:     if ($delta < 0) {
  765:         $inPast = 1;
  766:         $delta = -$delta;
  767:     }
  768: 
  769:     if ( $delta > 0 ) {
  770: 
  771:         my $tense = $inPast ? " ago" : "";
  772:         my $prefix = $inPast ? "" : "in ";
  773:         
  774:         # Less than a minute
  775:         if ( $delta < $minute ) {
  776:             if ($delta == 1) { return "${prefix}1 second$tense"; }
  777:             return "$prefix$delta seconds$tense";
  778:         }
  779: 
  780:         # Less than an hour
  781:         if ( $delta < $hour ) {
  782:             # If so, use minutes
  783:             my $minutes = floor($delta / 60);
  784:             if ($minutes == 1) { return "${prefix}1 minute$tense"; }
  785:             return "$prefix$minutes minutes$tense";
  786:         }
  787:         
  788:         # Is it less than 24 hours away? If so,
  789:         # display hours + minutes
  790:         if ( $delta < $hour * 24) {
  791:             my $hours = floor($delta / $hour);
  792:             my $minutes = floor(($delta % $hour) / $minute);
  793:             my $hourString = "$hours hours";
  794:             my $minuteString = ", $minutes minutes";
  795:             if ($hours == 1) {
  796:                 $hourString = "1 hour";
  797:             }
  798:             if ($minutes == 1) {
  799:                 $minuteString = ", 1 minute";
  800:             }
  801:             if ($minutes == 0) {
  802:                 $minuteString = "";
  803:             }
  804:             return "$prefix$hourString$minuteString$tense";
  805:         }
  806: 
  807: 	my $dt = DateTime->from_epoch(epoch => $time)
  808: 	                 ->set_time_zone(&Apache::lonlocal::gettimezone());
  809: 
  810: 	# If there's a caller supplied format, use it.
  811: 
  812: 	if ($format ne '') {
  813: 	    my $timeStr = $dt->strftime($format);
  814: 	    return $timeStr.' ('.$dt->time_zone_short_name().')';
  815: 	}
  816: 
  817:         # Less than 5 days away, display day of the week and
  818:         # HH:MM
  819: 
  820:         if ( $delta < $day * 5 ) {
  821:             my $timeStr = $dt->strftime("%A, %b %e at %I:%M %P (%Z)");
  822:             $timeStr =~ s/12:00 am/00:00/;
  823:             $timeStr =~ s/12:00 pm/noon/;
  824:             return ($inPast ? "last " : "this ") .
  825:                 $timeStr;
  826:         }
  827:         
  828: 	my $conjunction='on';
  829: 	if ($type eq 'start') {
  830: 	    $conjunction='at';
  831: 	} elsif ($type eq 'end') {
  832: 	    $conjunction='by';
  833: 	}
  834:         # Is it this year?
  835: 	my $dt_now = DateTime->from_epoch(epoch => $now)
  836: 	                     ->set_time_zone(&Apache::lonlocal::gettimezone());
  837:         if ( $dt->year() == $dt_now->year()) {
  838:             # Return on Month Day, HH:MM meridian
  839:             my $timeStr = $dt->strftime("$conjunction %A, %b %e at %I:%M %P (%Z)");
  840:             $timeStr =~ s/12:00 am/00:00/;
  841:             $timeStr =~ s/12:00 pm/noon/;
  842:             return $timeStr;
  843:         }
  844: 
  845:         # Not this year, so show the year
  846:         my $timeStr = 
  847: 	    $dt->strftime("$conjunction %A, %b %e %Y at %I:%M %P (%Z)");
  848:         $timeStr =~ s/12:00 am/00:00/;
  849:         $timeStr =~ s/12:00 pm/noon/;
  850:         return $timeStr;
  851:     }
  852: }
  853: 
  854: 
  855: sub resource { return 0; }
  856: sub communication_status { return 1; }
  857: sub quick_status { return 2; }
  858: sub long_status { return 3; }
  859: sub part_status_summary { return 4; }
  860: 
  861: sub render_resource {
  862:     my ($resource, $part, $params) = @_;
  863: 
  864:     my $nonLinkedText = ''; # stuff after resource title not in link
  865: 
  866:     my $link = $params->{"resourceLink"};
  867: 
  868:     #  The URL part is not escaped at this point, but the symb is... 
  869: 
  870:     my $src = $resource->src();
  871:     my $it = $params->{"iterator"};
  872:     my $filter = $it->{FILTER};
  873: 
  874:     my $title = $resource->compTitle();
  875: 
  876:     my $partLabel = "";
  877:     my $newBranchText = "";
  878:     my $location=&Apache::loncommon::lonhttpdurl("/adm/lonIcons");
  879:     # If this is a new branch, label it so
  880:     if ($params->{'isNewBranch'}) {
  881:         $newBranchText = "<img src='$location/branch.gif' alt=".mt('Branch')." />";
  882:     }
  883: 
  884:     # links to open and close the folder
  885: 
  886:     my $whitespace = $location.'/whitespace_21.gif';
  887:     my $linkopen = "<img src='$whitespace' alt='' />"."<a href=\"$link\">";
  888:     my $linkclose = "</a>";
  889: 
  890:     # Default icon: unknown page
  891:     my $icon = "<img class=\"LC_contentImage\" src='$location/unknown.gif' alt='' />";
  892:     
  893:     if ($resource->is_problem()) {
  894:         if ($part eq '0' || $params->{'condensed'}) {
  895: 	    $icon = '<img class="LC_contentImage" src="'.$location.'/';
  896: 	    if ($resource->is_task()) {
  897: 		$icon .= 'task.gif" alt="'.&mt('Task');
  898: 	    } else {
  899: 		$icon .= 'problem.gif" alt="'.&mt('Problem');
  900: 	    }
  901: 	    $icon .='" />';
  902:         } else {
  903:             $icon = $params->{'indentString'};
  904:         }
  905:     } else {
  906: 	$icon = "<img class=\"LC_contentImage\" src='".&Apache::loncommon::icon($resource->src)."' alt='' />";
  907:     }
  908: 
  909:     # Display the correct map icon to open or shut map
  910:     if ($resource->is_map()) {
  911:         my $mapId = $resource->map_pc();
  912:         my $nowOpen = !defined($filter->{$mapId});
  913:         if ($it->{CONDITION}) {
  914:             $nowOpen = !$nowOpen;
  915:         }
  916: 	
  917: 	my $folderType = $resource->is_sequence() ? 'folder' : 'page';
  918:         my $title=$resource->title;
  919: 		$title=~s/\"/\&qout;/g;
  920:         if (!$params->{'resource_no_folder_link'}) {
  921:             $icon = "navmap.$folderType." . ($nowOpen ? 'closed' : 'open') . '.gif';
  922:             $icon = "<img src='$location/arrow." . ($nowOpen ? 'closed' : 'open') . ".gif' alt='' />"
  923:                     ."<img class=\"LC_contentImage\" src='$location/$icon' alt=\""
  924:                     .($nowOpen ? &mt('Open Folder') : &mt('Close Folder')).' '.$title."\" />";			
  925:             $linkopen = "<a href=\"" . $params->{'url'} . '?' . 
  926:                 $params->{'queryString'} . '&amp;filter=';
  927:             $linkopen .= ($nowOpen xor $it->{CONDITION}) ?
  928:                 addToFilter($filter, $mapId) :
  929:                 removeFromFilter($filter, $mapId);
  930:             $linkopen .= "&amp;condition=" . $it->{CONDITION} . '&amp;hereType='
  931:                 . $params->{'hereType'} . '&amp;here=' .
  932:                 &escape($params->{'here'}) . 
  933:                 '&amp;jump=' .
  934:                 &escape($resource->symb()) . 
  935:                 "&amp;folderManip=1\">";
  936: 
  937:         } else {
  938:             # Don't allow users to manipulate folder
  939:             $icon = "navmap.$folderType." . ($nowOpen ? 'closed' : 'open') . '.gif';
  940:             $icon = "<img class=\"LC_space\" src='$whitespace' alt='' />"."<img class=\"LC_contentImage\" src='$location/$icon' alt=\"".($nowOpen ? &mt('Open Folder') : &mt('Close Folder')).' '.$title."\" />";
  941: 
  942:             $linkopen = "";
  943:             $linkclose = "";
  944:         }
  945:     }
  946: 
  947:     if ($resource->randomout()) {
  948:         $nonLinkedText .= ' <i>('.&mt('hidden').')</i> ';
  949:     }
  950:     if (!$resource->condval()) {
  951:         $nonLinkedText .= ' <i>('.&mt('conditionally hidden').')</i> ';
  952:     }
  953:     if (($resource->is_practice()) && ($resource->is_raw_problem())) {
  954:         $nonLinkedText .=' <font color="green"><b>'.&mt('not graded').'</b></font>';
  955:     }
  956: 
  957:     # We're done preparing and finally ready to start the rendering
  958:     my $result = '<td class="LC_middle">';
  959:     my $newfolderType = $resource->is_sequence() ? 'folder' : 'page';
  960: 	
  961:     my $indentLevel = $params->{'indentLevel'};
  962:     if ($newBranchText) { $indentLevel--; }
  963: 
  964:     # print indentation
  965:     for (my $i = 0; $i < $indentLevel; $i++) {
  966:         $result .= $params->{'indentString'};
  967:     }
  968: 
  969:     # Decide what to display
  970:     $result .= "$newBranchText$linkopen$icon$linkclose";
  971:     
  972:     my $curMarkerBegin = '';
  973:     my $curMarkerEnd = '';
  974: 
  975:     # Is this the current resource?
  976:     if (!$params->{'displayedHereMarker'} && 
  977:         $resource->symb() eq $params->{'here'} ) {
  978:         $curMarkerBegin = '<em>';
  979:         $curMarkerEnd = '</em>';
  980: 	$params->{'displayedHereMarker'} = 1;
  981:     }
  982: 
  983:     if ($resource->is_problem() && $part ne '0' && 
  984:         !$params->{'condensed'}) {
  985: 	my $displaypart=$resource->part_display($part);
  986:         $partLabel = " (".&mt('Part: [_1]', $displaypart).")";
  987: 	if ($link!~/\#/) { $link.='#'.&escape($part); }
  988:         $title = "";
  989:     }
  990: 
  991:     if ($params->{'condensed'} && $resource->countParts() > 1) {
  992:         $nonLinkedText .= ' ('.&mt('[_1] parts', $resource->countParts()).')';
  993:     }
  994: 
  995:     if (!$params->{'resource_nolink'} && !$resource->is_sequence() && !$resource->is_empty_sequence) {
  996:         $result .= "$curMarkerBegin<a href=\"$link\">$title$partLabel</a>$curMarkerEnd$nonLinkedText</td>";
  997:     } else {
  998:         $result .= "$curMarkerBegin$linkopen$title$partLabel</a>$curMarkerEnd$nonLinkedText</td>";
  999:     }
 1000: 
 1001:     return $result;
 1002: }
 1003: 
 1004: sub render_communication_status {
 1005:     my ($resource, $part, $params) = @_;
 1006:     my $discussionHTML = ""; my $feedbackHTML = ""; my $errorHTML = "";
 1007: 
 1008:     my $link = $params->{"resourceLink"};
 1009:     my $linkopen = "<a href=\"$link\">";
 1010:     my $linkclose = "</a>";
 1011:     my $location=&Apache::loncommon::lonhttpdurl("/adm/lonMisc");
 1012:     if ($resource->hasDiscussion()) {
 1013:         $discussionHTML = $linkopen .
 1014:             '<img alt="'.&mt('New Discussion').'" src="'.$location.'/chat.gif" title="'.&mt('New Discussion').'"/>' .
 1015:             $linkclose;
 1016:     }
 1017:     
 1018:     if ($resource->getFeedback()) {
 1019:         my $feedback = $resource->getFeedback();
 1020:         foreach my $msgid (split(/\,/, $feedback)) {
 1021:             if ($msgid) {
 1022:                 $feedbackHTML .= '&nbsp;<a href="/adm/email?display='
 1023:                     . &escape($msgid) . '">'
 1024:                     . '<img alt="'.&mt('New E-mail').'" src="'.$location.'/feedback.gif" title="'.&mt('New E-mail').'"/></a>';
 1025:             }
 1026:         }
 1027:     }
 1028:     
 1029:     if ($resource->getErrors()) {
 1030:         my $errors = $resource->getErrors();
 1031:         my $errorcount = 0;
 1032:         foreach my $msgid (split(/,/, $errors)) {
 1033:             last if ($errorcount>=10); # Only output 10 bombs maximum
 1034:             if ($msgid) {
 1035:                 $errorcount++;
 1036:                 $errorHTML .= '&nbsp;<a href="/adm/email?display='
 1037:                     . &escape($msgid) . '">'
 1038:                     . '<img alt="'.&mt('New Error').'" src="'.$location.'/bomb.gif" title="'.&mt('New Error').'"/></a>';
 1039:             }
 1040:         }
 1041:     }
 1042: 
 1043:     if ($params->{'multipart'} && $part != '0') {
 1044: 	$discussionHTML = $feedbackHTML = $errorHTML = '';
 1045:     }
 1046:     return "<td class=\"LC_middle\">$discussionHTML$feedbackHTML$errorHTML&nbsp;</td>";
 1047: 
 1048: }
 1049: sub render_quick_status {
 1050:     my ($resource, $part, $params) = @_;
 1051:     my $result = "";
 1052:     my $firstDisplayed = !$params->{'condensed'} && 
 1053:         $params->{'multipart'} && $part eq "0";
 1054: 
 1055:     my $link = $params->{"resourceLink"};
 1056:     my $linkopen = "<a href=\"$link\">";
 1057:     my $linkclose = "</a>";
 1058: 	
 1059: 	$result .= '<td class="LC_middle">';
 1060:     if ($resource->is_problem() &&
 1061:         !$firstDisplayed) {
 1062:         my $icon = $statusIconMap{$resource->simpleStatus($part)};
 1063:         my $alt = $iconAltTags{$icon};
 1064:         if ($icon) {
 1065: 	    my $location=
 1066: 		&Apache::loncommon::lonhttpdurl("/adm/lonIcons/$icon");
 1067: 		$result .= $linkopen.'<img src="'.$location.'" alt="'.&mt($alt).'" title="'.&mt($alt).'" />'.$linkclose;            
 1068:         } else {
 1069:             $result .= "&nbsp;";
 1070:         }
 1071:     } else { # not problem, no icon
 1072:         $result .= "&nbsp;";
 1073:     }
 1074: 	$result .= "</td>\n";
 1075:     return $result;
 1076: }
 1077: sub render_long_status {
 1078:     my ($resource, $part, $params) = @_;
 1079:     my $result = '<td class="LC_middle LC_right">';
 1080:     my $firstDisplayed = !$params->{'condensed'} && 
 1081:         $params->{'multipart'} && $part eq "0";
 1082:                 
 1083:     my $color;
 1084:     if ($resource->is_problem() || $resource->is_practice()) {
 1085:         $color = $colormap{$resource->status};
 1086:         
 1087:         if (dueInLessThan24Hours($resource, $part) ||
 1088:             lastTry($resource, $part)) {
 1089:             $color = $hurryUpColor;
 1090:         }
 1091:     }
 1092:     
 1093:     if ($resource->kind() eq "res" &&
 1094:         ($resource->is_problem() || $resource->is_practice()) &&
 1095:         !$firstDisplayed) {
 1096:         if ($color) {$result .= "<font color=\"$color\"><b>"; }
 1097:         $result .= getDescription($resource, $part);
 1098:         if ($color) {$result .= "</b></font>"; }
 1099:     }
 1100:     if ($resource->is_map() && &advancedUser() && $resource->randompick()) {
 1101:         $result .= &mt('(randomly select [_1])', $resource->randompick());
 1102:     }
 1103:     if ($resource->is_map() && &advancedUser() && $resource->randomorder()) {
 1104:         $result .= &mt('(randomly ordered)');
 1105:     }
 1106: 
 1107:     # Debugging code
 1108:     #$result .= " " . $resource->awarded($part) . '/' . $resource->weight($part) .
 1109:     #	' - Part: ' . $part;
 1110: 
 1111:     $result .= "</td>\n";
 1112:     
 1113:     return $result;
 1114: }
 1115: 
 1116: # Colors obtained by taking the icons, matching the colors, and
 1117: # possibly reducing the Value (HSV) of the color, if it's too bright
 1118: # for text, generally by one third or so.
 1119: my %statusColors = 
 1120:     (
 1121:      $resObj->CLOSED => '#000000',
 1122:      $resObj->OPEN   => '#998b13',
 1123:      $resObj->CORRECT => '#26933f',
 1124:      $resObj->INCORRECT => '#c48207',
 1125:      $resObj->ATTEMPTED => '#a87510',
 1126:      $resObj->ERROR => '#000000'
 1127:      );
 1128: my %statusStrings = 
 1129:     (
 1130:      $resObj->CLOSED => 'Not yet open',
 1131:      $resObj->OPEN   => 'Open',
 1132:      $resObj->CORRECT => 'Correct',
 1133:      $resObj->INCORRECT => 'Incorrect',
 1134:      $resObj->ATTEMPTED => 'Attempted',
 1135:      $resObj->ERROR => 'Network Error'
 1136:      );
 1137: my @statuses = ($resObj->CORRECT, $resObj->ATTEMPTED, $resObj->INCORRECT, $resObj->OPEN, $resObj->CLOSED, $resObj->ERROR);
 1138: 
 1139: sub render_parts_summary_status {
 1140:     my ($resource, $part, $params) = @_;
 1141:     if (!$resource->is_problem() && !$resource->contains_problem) { return '<td></td>'; }
 1142:     if ($params->{showParts}) { 
 1143: 	return '<td></td>';
 1144:     }
 1145: 
 1146:     my $td = "<td align='right'>\n";
 1147:     my $endtd = "</td>\n";
 1148:     my @probs;
 1149: 
 1150:     if ($resource->contains_problem) {
 1151: 	@probs=$resource->retrieveResources($resource,sub { $_[0]->is_problem() },1,0);
 1152:     } else {
 1153: 	@probs=($resource);
 1154:     }
 1155:     my $return;
 1156:     my %overallstatus;
 1157:     my $totalParts;
 1158:     foreach my $resource (@probs) {
 1159: 	# If there is a single part, just show the simple status
 1160: 	if ($resource->singlepart()) {
 1161: 	    my $status = $resource->simpleStatus(${$resource->parts}[0]);
 1162: 	    $overallstatus{$status}++;
 1163: 	    $totalParts++;
 1164: 	    next;
 1165: 	}
 1166: 	# Now we can be sure the $part doesn't really matter.
 1167: 	my $statusCount = $resource->simpleStatusCount();
 1168: 	my @counts;
 1169: 	foreach my $status (@statuses) {
 1170: 	    # decouple display order from the simpleStatusCount order
 1171: 	    my $slot = Apache::lonnavmaps::resource::statusToSlot($status);
 1172: 	    if ($statusCount->[$slot]) {
 1173: 		$overallstatus{$status}+=$statusCount->[$slot];
 1174: 		$totalParts+=$statusCount->[$slot];
 1175: 	    }
 1176: 	}
 1177:     }
 1178:     $return.= $td . $totalParts . ' parts: ';
 1179:     foreach my $status (@statuses) {
 1180: 	if ($overallstatus{$status}) {
 1181: 	    $return.="<font color='" . $statusColors{$status} .
 1182: 		"'>" . $overallstatus{$status} . ' '
 1183: 		. $statusStrings{$status} . "</font>";
 1184: 	}
 1185:     }
 1186:     $return.= $endtd;
 1187:     return $return;
 1188: }
 1189: 
 1190: my @preparedColumns = (\&render_resource, \&render_communication_status,
 1191:                        \&render_quick_status, \&render_long_status,
 1192: 		       \&render_parts_summary_status);
 1193: 
 1194: sub setDefault {
 1195:     my ($val, $default) = @_;
 1196:     if (!defined($val)) { return $default; }
 1197:     return $val;
 1198: }
 1199: 
 1200: sub cmp_title {
 1201:     my ($atitle,$btitle) = (lc($_[0]->compTitle),lc($_[1]->compTitle));
 1202:     $atitle=~s/^\s*//;
 1203:     $btitle=~s/^\s*//;
 1204:     return $atitle cmp $btitle;
 1205: }
 1206: 
 1207: sub render {
 1208:     my $args = shift;
 1209:     &Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING});
 1210:     my $result = '';
 1211:     # Configure the renderer.
 1212:     my $cols = $args->{'cols'};
 1213:     if (!defined($cols)) {
 1214:         # no columns, no nav maps.
 1215:         return '';
 1216:     }
 1217:     my $navmap;
 1218:     if (defined($args->{'navmap'})) {
 1219:         $navmap = $args->{'navmap'};
 1220:     }
 1221: 
 1222:     my $r = $args->{'r'};
 1223:     my $queryString = $args->{'queryString'};
 1224:     my $jump = $args->{'jump'};
 1225:     my $here = $args->{'here'};
 1226:     my $suppressNavmap = setDefault($args->{'suppressNavmap'}, 0);
 1227:     my $closeAllPages = setDefault($args->{'closeAllPages'}, 0);
 1228:     my $currentJumpDelta = 2; # change this to change how many resources are displayed
 1229:                              # before the current resource when using #current
 1230: 
 1231:     # If we were passed 'here' information, we are not rendering
 1232:     # after a folder manipulation, and we were not passed an
 1233:     # iterator, make sure we open the folders to show the "here"
 1234:     # marker
 1235:     my $filterHash = {};
 1236:     # Figure out what we're not displaying
 1237:     foreach my $item (split(/\,/, $env{"form.filter"})) {
 1238:         if ($item) {
 1239:             $filterHash->{$item} = "1";
 1240:         }
 1241:     }
 1242: 
 1243:     # Filter: Remember filter function and add our own filter: Refuse
 1244:     # to show hidden resources unless the user can see them.
 1245:     my $userCanSeeHidden = advancedUser();
 1246:     my $filterFunc = setDefault($args->{'filterFunc'},
 1247:                                 sub {return 1;});
 1248:     if (!$userCanSeeHidden) {
 1249:         # Without renaming the filterfunc, the server seems to go into
 1250:         # an infinite loop
 1251:         my $oldFilterFunc = $filterFunc;
 1252:         $filterFunc = sub { my $res = shift; return !$res->randomout() && 
 1253:                                 &$oldFilterFunc($res);};
 1254:     }
 1255: 
 1256:     my $condition = 0;
 1257:     if ($env{'form.condition'}) {
 1258:         $condition = 1;
 1259:     }
 1260: 
 1261:     if (!$env{'form.folderManip'} && !defined($args->{'iterator'})) {
 1262:         # Step 1: Check to see if we have a navmap
 1263:         if (!defined($navmap)) {
 1264:             $navmap = Apache::lonnavmaps::navmap->new();
 1265: 	    if (!defined($navmap)) {
 1266: 		# no longer in course
 1267: 		return '<span class="LC_error">'.&mt('No course selected').'</span><br />
 1268:                         <a href="/adm/roles">'.&mt('Select a course').'</a><br />';
 1269: 	    }
 1270: 	}
 1271: 
 1272:         # Step two: Locate what kind of here marker is necessary
 1273:         # Determine where the "here" marker is and where the screen jumps to.
 1274: 
 1275:         if ($env{'form.postsymb'} ne '') {
 1276:             $here = $jump = &Apache::lonnet::symbclean($env{'form.postsymb'});
 1277:         } elsif ($env{'form.postdata'} ne '') {
 1278:             # couldn't find a symb, is there a URL?
 1279:             my $currenturl = $env{'form.postdata'};
 1280:             #$currenturl=~s/^http\:\/\///;
 1281:             #$currenturl=~s/^[^\/]+//;
 1282:             
 1283:             $here = $jump = &Apache::lonnet::symbread($currenturl);
 1284: 	}
 1285: 	if ($here eq '') {
 1286: 	    my $last;
 1287: 	    if (tie(my %hash,'GDBM_File',$env{'request.course.fn'}.'_symb.db',
 1288:                     &GDBM_READER(),0640)) {
 1289: 		$last=$hash{'last_known'};
 1290: 		untie(%hash);
 1291: 	    }
 1292: 	    if ($last) { $here = $jump = $last; }
 1293: 	}
 1294: 
 1295:         # Step three: Ensure the folders are open
 1296:         my $mapIterator = $navmap->getIterator(undef, undef, undef, 1);
 1297:         my $curRes;
 1298:         my $found = 0;
 1299:         
 1300:         # We only need to do this if we need to open the maps to show the
 1301:         # current position. This will change the counter so we can't count
 1302:         # for the jump marker with this loop.
 1303:         while ($here && ($curRes = $mapIterator->next()) && !$found) {
 1304:             if (ref($curRes) && $curRes->symb() eq $here) {
 1305:                 my $mapStack = $mapIterator->getStack();
 1306:                 
 1307:                 # Ensure the parent maps are open
 1308:                 for my $map (@{$mapStack}) {
 1309:                     if ($condition) {
 1310:                         undef $filterHash->{$map->map_pc()};
 1311:                     } else {
 1312:                         $filterHash->{$map->map_pc()} = 1;
 1313:                     }
 1314:                 }
 1315:                 $found = 1;
 1316:             }
 1317:         }            
 1318:     }        
 1319: 
 1320:     if ( !defined($args->{'iterator'}) && $env{'form.folderManip'} ) { # we came from a user's manipulation of the nav page
 1321:         # If this is a click on a folder or something, we want to preserve the "here"
 1322:         # from the querystring, and get the new "jump" marker
 1323:         $here = $env{'form.here'};
 1324:         $jump = $env{'form.jump'};
 1325:     } 
 1326:     
 1327:     my $it = $args->{'iterator'};
 1328:     if (!defined($it)) {
 1329:         # Construct a default iterator based on $env{'form.'} information
 1330:         
 1331:         # Step 1: Check to see if we have a navmap
 1332:         if (!defined($navmap)) {
 1333:             $navmap = Apache::lonnavmaps::navmap->new();
 1334:             if (!defined($navmap)) {
 1335:                 # no longer in course
 1336:                 return '<span class="LC_error">'.&mt('No course selected').'</span><br />
 1337:                         <a href="/adm/roles">'.&mt('Select a course').'</a><br />';
 1338:             }
 1339:         }
 1340: 
 1341:         # See if we're being passed a specific map
 1342:         if ($args->{'iterator_map'}) {
 1343:             my $map = $args->{'iterator_map'};
 1344:             $map = $navmap->getResourceByUrl($map);
 1345:             my $firstResource = $map->map_start();
 1346:             my $finishResource = $map->map_finish();
 1347: 
 1348:             $args->{'iterator'} = $it = $navmap->getIterator($firstResource, $finishResource, $filterHash, $condition);
 1349:         } else {
 1350:             $args->{'iterator'} = $it = $navmap->getIterator(undef, undef, $filterHash, $condition,undef,$args->{'include_top_level_map'});
 1351:         }
 1352:     }
 1353: 
 1354:     # (re-)Locate the jump point, if any
 1355:     # Note this does not take filtering or hidden into account... need
 1356:     # to be fixed?
 1357:     my $mapIterator = $navmap->getIterator(undef, undef, $filterHash, 0);
 1358:     my $curRes;
 1359:     my $foundJump = 0;
 1360:     my $counter = 0;
 1361:     
 1362:     while (($curRes = $mapIterator->next()) && !$foundJump) {
 1363:         if (ref($curRes)) { $counter++; }
 1364:         
 1365:         if (ref($curRes) && $jump eq $curRes->symb()) {
 1366:             
 1367:             # This is why we have to use the main iterator instead of the
 1368:             # potentially faster DFS: The count has to be the same, so
 1369:             # the order has to be the same, which DFS won't give us.
 1370:             $args->{'currentJumpIndex'} = $counter;
 1371:             $foundJump = 1;
 1372:         }
 1373:     }
 1374: 
 1375:     my $showParts = setDefault($args->{'showParts'}, 1);
 1376:     my $condenseParts = setDefault($args->{'condenseParts'}, 1);
 1377:     # keeps track of when the current resource is found,
 1378:     # so we can back up a few and put the anchor above the
 1379:     # current resource
 1380:     my $printKey = $args->{'printKey'};
 1381:     my $printCloseAll = $args->{'printCloseAll'};
 1382:     if (!defined($printCloseAll)) { $printCloseAll = 1; }
 1383:    
 1384:     # Print key?
 1385:     if ($printKey) {
 1386:         $result .= '<table border="0" cellpadding="2" cellspacing="0">';
 1387:         $result.='<tr><td align="right" valign="bottom">Key:&nbsp;&nbsp;</td>';
 1388: 	my $location=&Apache::loncommon::lonhttpdurl("/adm/lonMisc");
 1389:         if ($navmap->{LAST_CHECK}) {
 1390:             $result .= 
 1391:                 '<img src="'.$location.'/chat.gif" alt="" /> '.&mt('New discussion since').' '.
 1392:                 strftime("%A, %b %e at %I:%M %P", localtime($navmap->{LAST_CHECK})).
 1393:                 '</td><td align="center" valign="bottom">&nbsp;&nbsp;'.
 1394:                 '<img src="'.$location.'/feedback.gif" alt="" /> '.&mt('New message (click to open)').'<p>'.
 1395:                 '</td>'; 
 1396:         } else {
 1397:             $result .= '<td align="center" valign="bottom">&nbsp;&nbsp;'.
 1398:                 '<img src="'.$location.'/chat.gif" alt="" /> '.&mt('Discussions').'</td><td align="center" valign="bottom">'.
 1399:                 '&nbsp;&nbsp;<img src="'.$location.'/feedback.gif" alt="" /> '.&mt('New message (click to open)').
 1400:                 '</td>'; 
 1401:         }
 1402: 
 1403:         $result .= '</tr></table>';
 1404:     }
 1405: 
 1406:     if ($printCloseAll && !$args->{'resource_no_folder_link'}) {
 1407: 	my ($link,$text);
 1408:         if ($condition) {
 1409: 	    $link='navmaps?condition=0&amp;filter=&amp;'.$queryString.
 1410: 		'&amp;here='.&escape($here);
 1411: 	    $text='Close all folders';
 1412:         } else {
 1413: 	    $link='navmaps?condition=1&amp;filter=&amp;'.$queryString.
 1414: 		'&amp;here='.&escape($here);
 1415: 	    $text='Open all folders';
 1416:         }
 1417:         if ($env{'form.register'}) {
 1418:             $link .= '&amp;register='.$env{'form.register'};
 1419:         }
 1420: 	if ($args->{'caller'} eq 'navmapsdisplay') {
 1421: 	    &add_linkitem($args->{'linkitems'},'changefolder',
 1422: 			  "location.href='$link'",$text);
 1423: 	} else {
 1424: 	    $result.= '<a href="'.$link.'">'.&mt($text).'</a>';
 1425: 	}
 1426:         $result .= "\n";
 1427:     }
 1428: 
 1429:     # Check for any unread discussions in all resources.
 1430:     if ($args->{'caller'} eq 'navmapsdisplay') {
 1431: 	&add_linkitem($args->{'linkitems'},'clearbubbles',
 1432: 		      'document.clearbubbles.submit()',
 1433: 		      'Mark all posts read');
 1434: 	my $time=time;
 1435: 	$result .= (<<END);
 1436:     <form name="clearbubbles" method="post" action="/adm/feedback">
 1437: 	<input type="hidden" name="navurl" value="$ENV{'QUERY_STRING'}" />
 1438: 	<input type="hidden" name="navtime" value="$time" />
 1439: END
 1440:         if ($env{'form.register'}) {
 1441:             $result .= '<input type="hidden" name="register" value="'.$env{'form.register'}.'" />';
 1442:         }
 1443:         if ($args->{'sort'} eq 'discussion') { 
 1444: 	    my $totdisc = 0;
 1445: 	    my $haveDisc = '';
 1446: 	    my @allres=$navmap->retrieveResources();
 1447: 	    foreach my $resource (@allres) {
 1448: 		if ($resource->hasDiscussion()) {
 1449: 		    $haveDisc .= $resource->wrap_symb().':';
 1450: 		    $totdisc ++;
 1451: 		}
 1452: 	    }
 1453: 	    if ($totdisc > 0) {
 1454: 		$haveDisc =~ s/:$//;
 1455: 		$result .= (<<END);
 1456: 	<input type="hidden" name="navmaps" value="$haveDisc" />
 1457:     </form>
 1458: END
 1459:             }
 1460: 	}
 1461: 	$result.='</form>';
 1462:     }
 1463: 
 1464:     if ($args->{'caller'} eq 'navmapsdisplay') {
 1465:         $result .= '<table><tr><td>'.
 1466:                    &Apache::loncommon::help_open_menu('Navigation Screen','Navigation_Screen',undef,'RAT').'</td>';
 1467: 	    $result .= '<td>&nbsp;</td>'; 
 1468: 	$result.='<td class="LC_middle">'.&mt('Tools:').'</td>';
 1469: 	$result.=&show_linkitems_toolbar($args->{'linkitems'});
 1470:         if ($args->{'sort_html'}) {
 1471:             $result.='<td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td>'.
 1472:                 '<td align="right">'.$args->{'sort_html'}.'</td></tr>';
 1473:         }
 1474:         $result .= '</table>';
 1475:     } elsif ($args->{'sort_html'}) { 
 1476:         $result.=$args->{'sort_html'}; 
 1477:     }
 1478: 
 1479:     #$result .= "<br />\n";
 1480:     if ($r) {
 1481:         $r->print($result);
 1482:         $r->rflush();
 1483:         $result = "";
 1484:     }
 1485:     # End parameter setting
 1486:     
 1487:     $result .= "<br />\n";
 1488: 
 1489:     # Data
 1490:     $result.=&Apache::loncommon::start_data_table("LC_tableOfContent");    
 1491: 
 1492:     my $res = "Apache::lonnavmaps::resource";
 1493:     my %condenseStatuses =
 1494:         ( $res->NETWORK_FAILURE    => 1,
 1495:           $res->NOTHING_SET        => 1,
 1496:           $res->CORRECT            => 1 );
 1497: 
 1498:     # Shared variables
 1499:     $args->{'counter'} = 0; # counts the rows
 1500:     $args->{'indentLevel'} = 0;
 1501:     $args->{'isNewBranch'} = 0;
 1502:     $args->{'condensed'} = 0;   
 1503: 
 1504:     my $location = &Apache::loncommon::lonhttpdurl("/adm/lonIcons/whitespace_21.gif");
 1505:     $args->{'indentString'} = setDefault($args->{'indentString'}, "<img src='$location' alt='' />");
 1506:     $args->{'displayedHereMarker'} = 0;
 1507: 
 1508:     # If we're suppressing empty sequences, look for them here. Use DFS for speed,
 1509:     # since structure actually doesn't matter, except what map has what resources.
 1510:     if ($args->{'suppressEmptySequences'}) {
 1511:         my $dfsit = Apache::lonnavmaps::DFSiterator->new($navmap,
 1512:                                                          $it->{FIRST_RESOURCE},
 1513:                                                          $it->{FINISH_RESOURCE},
 1514:                                                          {}, undef, 1);
 1515:         my $depth = 0;
 1516:         $dfsit->next();
 1517:         my $curRes = $dfsit->next();
 1518:         while ($depth > -1) {
 1519:             if ($curRes == $dfsit->BEGIN_MAP()) { $depth++; }
 1520:             if ($curRes == $dfsit->END_MAP()) { $depth--; }
 1521: 
 1522:             if (ref($curRes)) { 
 1523:                 # Parallel pre-processing: Do sequences have non-filtered-out children?
 1524:                 if ($curRes->is_map()) {
 1525:                     $curRes->{DATA}->{HAS_VISIBLE_CHILDREN} = 0;
 1526:                     # Sequences themselves do not count as visible children,
 1527:                     # unless those sequences also have visible children.
 1528:                     # This means if a sequence appears, there's a "promise"
 1529:                     # that there's something under it if you open it, somewhere.
 1530:                 } else {
 1531:                     # Not a sequence: if it's filtered, ignore it, otherwise
 1532:                     # rise up the stack and mark the sequences as having children
 1533:                     if (&$filterFunc($curRes)) {
 1534:                         for my $sequence (@{$dfsit->getStack()}) {
 1535:                             $sequence->{DATA}->{HAS_VISIBLE_CHILDREN} = 1;
 1536:                         }
 1537:                     }
 1538:                 }
 1539:             }
 1540:         } continue {
 1541:             $curRes = $dfsit->next();
 1542:         }
 1543:     }
 1544: 
 1545:     my $displayedJumpMarker = 0;
 1546:     # Set up iteration.
 1547:     my $now = time();
 1548:     my $in24Hours = $now + 24 * 60 * 60;
 1549:     my $rownum = 0;
 1550: 
 1551:     # export "here" marker information
 1552:     $args->{'here'} = $here;
 1553: 
 1554:     $args->{'indentLevel'} = -1; # first BEGIN_MAP takes this to 0
 1555:     my @resources;
 1556:     my $code='';# sub { !(shift->is_map();) };
 1557:     if ($args->{'sort'} eq 'title') {
 1558:         my $oldFilterFunc = $filterFunc;
 1559: 	my $filterFunc= 
 1560: 	    sub {
 1561: 		my ($res)=@_;
 1562: 		if ($res->is_map()) { return 0;}
 1563: 		return &$oldFilterFunc($res);
 1564: 	    };
 1565: 	@resources=$navmap->retrieveResources(undef,$filterFunc);
 1566: 	@resources= sort { &cmp_title($a,$b) } @resources;
 1567:     } elsif ($args->{'sort'} eq 'duedate') {
 1568: 	my $oldFilterFunc = $filterFunc;
 1569: 	my $filterFunc= 
 1570: 	    sub {
 1571: 		my ($res)=@_;
 1572: 		if (!$res->is_problem()) { return 0;}
 1573: 		return &$oldFilterFunc($res);
 1574: 	    };
 1575: 	@resources=$navmap->retrieveResources(undef,$filterFunc);
 1576: 	@resources= sort {
 1577: 	    if ($a->duedate ne $b->duedate) {
 1578: 	        return $a->duedate cmp $b->duedate;
 1579: 	    }
 1580: 	    my $value=&cmp_title($a,$b);
 1581: 	    return $value;
 1582: 	} @resources;
 1583:     } elsif ($args->{'sort'} eq 'discussion') {
 1584: 	my $oldFilterFunc = $filterFunc;
 1585: 	my $filterFunc= 
 1586: 	    sub {
 1587: 		my ($res)=@_;
 1588: 		if (!$res->hasDiscussion() &&
 1589: 		    !$res->getFeedback() &&
 1590: 		    !$res->getErrors()) { return 0;}
 1591: 		return &$oldFilterFunc($res);
 1592: 	    };
 1593: 	@resources=$navmap->retrieveResources(undef,$filterFunc);
 1594: 	@resources= sort { &cmp_title($a,$b) } @resources;
 1595:     } else {
 1596: 	#unknow sort mechanism or default
 1597: 	undef($args->{'sort'});
 1598:     }
 1599: 
 1600: 
 1601:     while (1) {
 1602: 	if ($args->{'sort'}) {
 1603: 	    $curRes = shift(@resources);
 1604: 	} else {
 1605: 	    $curRes = $it->next($closeAllPages);
 1606: 	}
 1607: 	if (!$curRes) { last; }
 1608: 
 1609:         # Maintain indentation level.
 1610:         if ($curRes == $it->BEGIN_MAP() ||
 1611:             $curRes == $it->BEGIN_BRANCH() ) {
 1612:             $args->{'indentLevel'}++;
 1613:         }
 1614:         if ($curRes == $it->END_MAP() ||
 1615:             $curRes == $it->END_BRANCH() ) {
 1616:             $args->{'indentLevel'}--;
 1617:         }
 1618:         # Notice new branches
 1619:         if ($curRes == $it->BEGIN_BRANCH()) {
 1620:             $args->{'isNewBranch'} = 1;
 1621:         }
 1622: 
 1623:         # If this isn't an actual resource, continue on
 1624:         if (!ref($curRes)) {
 1625:             next;
 1626:         }
 1627: 
 1628:         # If this has been filtered out, continue on
 1629:         if (!(&$filterFunc($curRes))) {
 1630:             $args->{'isNewBranch'} = 0; # Don't falsely remember this
 1631:             next;
 1632:         } 
 1633: 
 1634:         # If this is an empty sequence and we're filtering them, continue on
 1635:         if ($curRes->is_map() && $args->{'suppressEmptySequences'} &&
 1636:             !$curRes->{DATA}->{HAS_VISIBLE_CHILDREN}) {
 1637:             next;
 1638:         }
 1639: 
 1640:         # If we're suppressing navmaps and this is a navmap, continue on
 1641:         if ($suppressNavmap && $curRes->src() =~ /^\/adm\/navmaps/) {
 1642:             next;
 1643:         }
 1644: 
 1645:         $args->{'counter'}++;
 1646: 
 1647:         # Does it have multiple parts?
 1648:         $args->{'multipart'} = 0;
 1649:         $args->{'condensed'} = 0;
 1650:         my @parts;
 1651:             
 1652:         # Decide what parts to show.
 1653:         if ($curRes->is_problem() && $showParts) {
 1654:             @parts = @{$curRes->parts()};
 1655:             $args->{'multipart'} = $curRes->multipart();
 1656:             
 1657:             if ($condenseParts) { # do the condensation
 1658:                 if (!$args->{'condensed'}) {
 1659:                     # Decide whether to condense based on similarity
 1660:                     my $status = $curRes->status($parts[0]);
 1661:                     my $due = $curRes->duedate($parts[0]);
 1662:                     my $open = $curRes->opendate($parts[0]);
 1663:                     my $statusAllSame = 1;
 1664:                     my $dueAllSame = 1;
 1665:                     my $openAllSame = 1;
 1666:                     for (my $i = 1; $i < scalar(@parts); $i++) {
 1667:                         if ($curRes->status($parts[$i]) != $status){
 1668:                             $statusAllSame = 0;
 1669:                         }
 1670:                         if ($curRes->duedate($parts[$i]) != $due ) {
 1671:                             $dueAllSame = 0;
 1672:                         }
 1673:                         if ($curRes->opendate($parts[$i]) != $open) {
 1674:                             $openAllSame = 0;
 1675:                         }
 1676:                     }
 1677:                     # $*allSame is true if all the statuses were
 1678:                     # the same. Now, if they are all the same and
 1679:                     # match one of the statuses to condense, or they
 1680:                     # are all open with the same due date, or they are
 1681:                     # all OPEN_LATER with the same open date, display the
 1682:                     # status of the first non-zero part (to get the 'correct'
 1683:                     # status right, since 0 is never 'correct' or 'open').
 1684:                     if (($statusAllSame && defined($condenseStatuses{$status})) ||
 1685:                         ($dueAllSame && $status == $curRes->OPEN && $statusAllSame)||
 1686:                         ($openAllSame && $status == $curRes->OPEN_LATER && $statusAllSame) ){
 1687:                         @parts = ($parts[0]);
 1688:                         $args->{'condensed'} = 1;
 1689:                     }
 1690:                 }
 1691: 		# Multipart problem with one part: always "condense" (happens
 1692: 		#  to match the desirable behavior)
 1693: 		if ($curRes->countParts() == 1) {
 1694: 		    @parts = ($parts[0]);
 1695: 		    $args->{'condensed'} = 1;
 1696: 		}
 1697:             }
 1698:         } 
 1699:             
 1700:         # If the multipart problem was condensed, "forget" it was multipart
 1701:         if (scalar(@parts) == 1) {
 1702:             $args->{'multipart'} = 0;
 1703:         } else {
 1704:             # Add part 0 so we display it correctly.
 1705:             unshift @parts, '0';
 1706:         }
 1707: 	
 1708: 	{
 1709: 	    my ($src,$symb,$anchor,$stack);
 1710: 	    if ($args->{'sort'}) {
 1711: 		my $it = $navmap->getIterator(undef, undef, undef, 1);
 1712: 		while ( my $res=$it->next()) {
 1713: 		    if (ref($res) &&
 1714: 			$res->symb() eq  $curRes->symb()) { last; }
 1715: 		}
 1716: 		$stack=$it->getStack();
 1717: 	    } else {
 1718: 		$stack=$it->getStack();
 1719: 	    }
 1720: 	    ($src,$symb,$anchor)=getLinkForResource($stack);
 1721: 	    if (defined($anchor)) { $anchor='#'.$anchor; }
 1722: 	    my $srcHasQuestion = $src =~ /\?/;
 1723: 	    $args->{"resourceLink"} = $src.
 1724: 		($srcHasQuestion?'&amp;':'?') .
 1725: 		'symb=' . &escape($symb).$anchor;
 1726: 	}
 1727:         # Now, we've decided what parts to show. Loop through them and
 1728:         # show them.
 1729:         foreach my $part (@parts) {
 1730:             $rownum ++;
 1731:             
 1732:             $result .= &Apache::loncommon::start_data_table_row();
 1733: 
 1734:             # Set up some data about the parts that the cols might want
 1735:             my $filter = $it->{FILTER};
 1736: 
 1737:             # Now, display each column.
 1738:             foreach my $col (@$cols) {
 1739:                 my $colHTML = '';
 1740:                 if (ref($col)) {
 1741:                     $colHTML .= &$col($curRes, $part, $args);
 1742:                 } else {
 1743:                     $colHTML .= &{$preparedColumns[$col]}($curRes, $part, $args);
 1744:                 }
 1745: 
 1746:                 # If this is the first column and it's time to print
 1747:                 # the anchor, do so
 1748:                 if ($col == $cols->[0] && 
 1749:                     $args->{'counter'} == $args->{'currentJumpIndex'} - 
 1750:                     $currentJumpDelta) {
 1751:                     # Jam the anchor after the <td> tag;
 1752:                     # necessary for valid HTML (which Mozilla requires)
 1753:                     $colHTML =~ s/\>/\>\<a name="curloc" \/\>/;
 1754:                     $displayedJumpMarker = 1;
 1755:                 }
 1756:                 $result .= $colHTML . "\n";
 1757:             }
 1758:             $result .= &Apache::loncommon::end_data_table_row();
 1759:             $args->{'isNewBranch'} = 0;
 1760:         }
 1761: 
 1762:         if ($r && $rownum % 20 == 0) {
 1763:             $r->print($result);
 1764:             $result = "";
 1765:             $r->rflush();
 1766:         }
 1767:     } continue {
 1768: 	if ($r) {
 1769: 	    # If we have the connection, make sure the user is still connected
 1770: 	    my $c = $r->connection;
 1771: 	    if ($c->aborted()) {
 1772: 		# Who cares what we do, nobody will see it anyhow.
 1773: 		return '';
 1774: 	    }
 1775: 	}
 1776:     }
 1777:     
 1778:     # Print out the part that jumps to #curloc if it exists
 1779:     # delay needed because the browser is processing the jump before
 1780:     # it finishes rendering, so it goes to the wrong place!
 1781:     # onload might be better, but this routine has no access to that.
 1782:     # On mozilla, the 0-millisecond timeout seems to prevent this;
 1783:     # it's quite likely this might fix other browsers, too, and 
 1784:     # certainly won't hurt anything.
 1785:     if ($displayedJumpMarker) {
 1786:         $result .= &Apache::lonhtmlcommon::scripttag("
 1787: if (location.href.indexOf('#curloc')==-1) {
 1788:     setTimeout(\"location += '#curloc';\", 0)
 1789: }
 1790: ");
 1791:     }
 1792: 
 1793:     $result.=&Apache::loncommon::end_data_table();
 1794: 
 1795:     if ($r) {
 1796:         $r->print($result);
 1797:         $result = "";
 1798:         $r->rflush();
 1799:     }
 1800:         
 1801:     return $result;
 1802: }
 1803: 
 1804: sub add_linkitem {
 1805:     my ($linkitems,$name,$cmd,$text)=@_;
 1806:     $$linkitems{$name}{'cmd'}=$cmd;
 1807:     $$linkitems{$name}{'text'}=&mt($text);
 1808: }
 1809: 
 1810: sub show_linkitems_toolbar {
 1811:     my ($linkitems,$condition)=@_;
 1812:     my @linkorder = ('firsthomework','everything','uncompleted',
 1813:                      'changefolder','clearbubbles');
 1814:     my $result .='<td align="left">'."\n". 
 1815:                  '<span class="LC_nobreak">'."\n".
 1816:                  '<ul id="LC_toolbar">';
 1817:     foreach my $link (@linkorder) {
 1818:         my $link_id = 'LC_content_toolbar_'.$link;
 1819:         if (defined($linkitems->{$link})) {
 1820:             if ($linkitems->{$link}{'text'} ne '') {
 1821:                 $linkitems->{$link}{'cmd'}=~s/"/'/g;
 1822:                 if ($linkitems->{$link}{'cmd'}) {
 1823:                     if ($link eq 'changefolder') {
 1824:                         if ($condition) {
 1825:                             $link_id='LC_content_toolbar_changefolder_toggled';
 1826:                         } else {
 1827:                             $link_id='LC_content_toolbar_changefolder';
 1828:                         }
 1829:                     }
 1830:                     $result .= '<li><a href="#" '.
 1831:                                'onclick="'.$linkitems->{$link}{'cmd'}.'" '.
 1832:                                'id="'.$link_id.'" '.
 1833:                                'class="LC_toolbarItem" '.
 1834:                                'title="'.$linkitems->{$link}{'text'}.'">'.
 1835:                                '</a></li>'."\n";
 1836:                 }
 1837:             }
 1838:         }
 1839:     }
 1840:     $result .= '</ul>'.
 1841:                '</span></td>'."\n";
 1842:     return $result;
 1843: }
 1844: 
 1845: 
 1846: 1;
 1847: 
 1848: 
 1849: 
 1850: 
 1851: 
 1852: 
 1853: 
 1854: 
 1855: 
 1856: package Apache::lonnavmaps::navmap;
 1857: 
 1858: =pod
 1859: 
 1860: =head1 Object: Apache::lonnavmaps::navmap
 1861: 
 1862: =head2 Overview
 1863: 
 1864: The navmap object's job is to provide access to the resources
 1865: in the course as Apache::lonnavmaps::resource objects, and to
 1866: query and manage the relationship between those resource objects.
 1867: 
 1868: Generally, you'll use the navmap object in one of three basic ways.
 1869: In order of increasing complexity and power:
 1870: 
 1871: =over 4
 1872: 
 1873: =item * C<$navmap-E<gt>getByX>, where X is B<Id>, B<Symb> or B<MapPc> and getResourceByUrl. This provides
 1874:     various ways to obtain resource objects, based on various identifiers.
 1875:     Use this when you want to request information about one object or 
 1876:     a handful of resources you already know the identities of, from some
 1877:     other source. For more about Ids, Symbs, and MapPcs, see the
 1878:     Resource documentation. Note that Url should be a B<last resort>,
 1879:     not your first choice; it only really works when there is only one
 1880:     instance of the resource in the course, which only applies to
 1881:     maps, and even that may change in the future (see the B<getResourceByUrl>
 1882:     documentation for more details.)
 1883: 
 1884: =item * C<my @resources = $navmap-E<gt>retrieveResources(args)>. This
 1885:     retrieves resources matching some criterion and returns them
 1886:     in a flat array, with no structure information. Use this when
 1887:     you are manipulating a series of resources, based on what map
 1888:     the are in, but do not care about branching, or exactly how
 1889:     the maps and resources are related. This is the most common case.
 1890: 
 1891: =item * C<$it = $navmap-E<gt>getIterator(args)>. This allows you traverse
 1892:     the course's navmap in various ways without writing the traversal
 1893:     code yourself. See iterator documentation below. Use this when
 1894:     you need to know absolutely everything about the course, including
 1895:     branches and the precise relationship between maps and resources.
 1896: 
 1897: =back
 1898: 
 1899: =head2 Creation And Destruction
 1900: 
 1901: To create a navmap object, use the following function:
 1902: 
 1903: =over 4
 1904: 
 1905: =item * B<Apache::lonnavmaps::navmap-E<gt>new>():
 1906: 
 1907: Creates a new navmap object. Returns the navmap object if this is
 1908: successful, or B<undef> if not.
 1909: 
 1910: =back
 1911: 
 1912: =head2 Methods
 1913: 
 1914: =over 4
 1915: 
 1916: =item * B<getIterator>(first, finish, filter, condition):
 1917: 
 1918: See iterator documentation below.
 1919: 
 1920: =cut
 1921: 
 1922: use strict;
 1923: use GDBM_File;
 1924: use Apache::lonnet;
 1925: use LONCAPA;
 1926: 
 1927: sub new {
 1928:     # magic invocation to create a class instance
 1929:     my $proto = shift;
 1930:     my $class = ref($proto) || $proto;
 1931:     my $self = {};
 1932: 
 1933:     # Resource cache stores navmap resources as we reference them. We generate
 1934:     # them on-demand so we don't pay for creating resources unless we use them.
 1935:     $self->{RESOURCE_CACHE} = {};
 1936: 
 1937:     # Network failure flag, if we accessed the course or user opt and
 1938:     # failed
 1939:     $self->{NETWORK_FAILURE} = 0;
 1940: 
 1941:     # tie the nav hash
 1942: 
 1943:     my %navmaphash;
 1944:     my %parmhash;
 1945:     my $courseFn = $env{"request.course.fn"};
 1946:     if (!(tie(%navmaphash, 'GDBM_File', "${courseFn}.db",
 1947:               &GDBM_READER(), 0640))) {
 1948:         return undef;
 1949:     }
 1950:     
 1951:     if (!(tie(%parmhash, 'GDBM_File', "${courseFn}_parms.db",
 1952:               &GDBM_READER(), 0640)))
 1953:     {
 1954:         untie %{$self->{PARM_HASH}};
 1955:         return undef;
 1956:     }
 1957: 
 1958:     $self->{NAV_HASH} = \%navmaphash;
 1959:     $self->{PARM_HASH} = \%parmhash;
 1960:     $self->{PARM_CACHE} = {};
 1961: 
 1962:     bless($self);
 1963:         
 1964:     return $self;
 1965: }
 1966: 
 1967: sub generate_course_user_opt {
 1968:     my $self = shift;
 1969:     if ($self->{COURSE_USER_OPT_GENERATED}) { return; }
 1970: 
 1971:     my $uname=$env{'user.name'};
 1972:     my $udom=$env{'user.domain'};
 1973:     my $cid=$env{'request.course.id'};
 1974:     my $cdom=$env{'course.'.$cid.'.domain'};
 1975:     my $cnum=$env{'course.'.$cid.'.num'};
 1976:     
 1977: # ------------------------------------------------- Get coursedata (if present)
 1978:     my $courseopt=&Apache::lonnet::get_courseresdata($cnum,$cdom);
 1979:     # Check for network failure
 1980:     if (!ref($courseopt)) {
 1981: 	if ( $courseopt =~ /no.such.host/i || $courseopt =~ /con_lost/i) {
 1982: 	    $self->{NETWORK_FAILURE} = 1;
 1983: 	}
 1984: 	undef($courseopt);
 1985:     }
 1986: 
 1987: # --------------------------------------------------- Get userdata (if present)
 1988: 	
 1989:     my $useropt=&Apache::lonnet::get_userresdata($uname,$udom);
 1990:     # Check for network failure
 1991:     if (!ref($useropt)) {
 1992: 	if ( $useropt =~ /no.such.host/i || $useropt =~ /con_lost/i) {
 1993: 	    $self->{NETWORK_FAILURE} = 1;
 1994: 	}
 1995: 	undef($useropt);
 1996:     }
 1997: 
 1998:     $self->{COURSE_OPT} = $courseopt;
 1999:     $self->{USER_OPT} = $useropt;
 2000: 
 2001:     $self->{COURSE_USER_OPT_GENERATED} = 1;
 2002:     
 2003:     return;
 2004: }
 2005: 
 2006: sub generate_email_discuss_status {
 2007:     my $self = shift;
 2008:     my $symb = shift;
 2009:     if ($self->{EMAIL_DISCUSS_GENERATED}) { return; }
 2010: 
 2011:     my $cid=$env{'request.course.id'};
 2012:     my $cdom=$env{'course.'.$cid.'.domain'};
 2013:     my $cnum=$env{'course.'.$cid.'.num'};
 2014:     
 2015:     my %emailstatus = &Apache::lonnet::dump('email_status');
 2016:     my $logoutTime = $emailstatus{'logout'};
 2017:     my $courseLeaveTime = $emailstatus{'logout_'.$env{'request.course.id'}};
 2018:     $self->{LAST_CHECK} = (($courseLeaveTime > $logoutTime) ?
 2019: 			   $courseLeaveTime : $logoutTime);
 2020:     my %discussiontime = &Apache::lonnet::dump('discussiontimes', 
 2021: 					       $cdom, $cnum);
 2022:     my %lastread = &Apache::lonnet::dump('nohist_'.$cid.'_discuss',
 2023:                                         $env{'user.domain'},$env{'user.name'},'lastread');
 2024:     my %lastreadtime = ();
 2025:     foreach my $key (keys %lastread) {
 2026:         my $shortkey = $key;
 2027:         $shortkey =~ s/_lastread$//;
 2028:         $lastreadtime{$shortkey} = $lastread{$key};
 2029:     }
 2030: 
 2031:     my %feedback=();
 2032:     my %error=();
 2033:     my @keys = &Apache::lonnet::getkeys('nohist_email',$env{'user.domain'},
 2034: 					$env{'user.name'});
 2035:     
 2036:     foreach my $msgid (@keys) {
 2037: 	if ((!$emailstatus{$msgid}) || ($emailstatus{$msgid} eq 'new')) {
 2038:             my ($sendtime,$shortsubj,$fromname,$fromdomain,$status,$fromcid,
 2039:                 $symb,$error) = &Apache::lonmsg::unpackmsgid($msgid);
 2040:             &Apache::lonenc::check_decrypt(\$symb); 
 2041:             if (($fromcid ne '') && ($fromcid ne $cid)) {
 2042:                 next;
 2043:             }
 2044:             if (defined($symb)) {
 2045:                 if (defined($error) && $error == 1) {
 2046:                     $error{$symb}.=','.$msgid;
 2047:                 } else {
 2048:                     $feedback{$symb}.=','.$msgid;
 2049:                 }
 2050:             } else {
 2051:                 my $plain=
 2052:                     &LONCAPA::unescape(&LONCAPA::unescape($msgid));
 2053:                 if ($plain=~/ \[([^\]]+)\]\:/) {
 2054:                     my $url=$1;
 2055:                     if ($plain=~/\:Error \[/) {
 2056:                         $error{$url}.=','.$msgid;
 2057:                     } else {
 2058:                         $feedback{$url}.=','.$msgid;
 2059:                     }
 2060:                 }
 2061:             }
 2062: 	}
 2063:     }
 2064:     
 2065:     #symbs of resources that have feedbacks (will be urls pre-2.3)
 2066:     $self->{FEEDBACK} = \%feedback;
 2067:     #or errors (will be urls pre 2.3)
 2068:     $self->{ERROR_MSG} = \%error;
 2069:     $self->{DISCUSSION_TIME} = \%discussiontime;
 2070:     $self->{EMAIL_STATUS} = \%emailstatus;
 2071:     $self->{LAST_READ} = \%lastreadtime;
 2072:     
 2073:     $self->{EMAIL_DISCUSS_GENERATED} = 1;
 2074: }
 2075: 
 2076: sub get_user_data {
 2077:     my $self = shift;
 2078:     if ($self->{RETRIEVED_USER_DATA}) { return; }
 2079: 
 2080:     # Retrieve performance data on problems
 2081:     my %student_data = Apache::lonnet::currentdump($env{'request.course.id'},
 2082: 						   $env{'user.domain'},
 2083: 						   $env{'user.name'});
 2084:     $self->{STUDENT_DATA} = \%student_data;
 2085: 
 2086:     $self->{RETRIEVED_USER_DATA} = 1;
 2087: }
 2088: 
 2089: sub get_discussion_data {
 2090:     my $self = shift;
 2091:     if ($self->{RETRIEVED_DISCUSSION_DATA}) {
 2092: 	return $self->{DISCUSSION_DATA};
 2093:     }
 2094: 
 2095:     $self->generate_email_discuss_status();    
 2096: 
 2097:     my $cid=$env{'request.course.id'};
 2098:     my $cdom=$env{'course.'.$cid.'.domain'};
 2099:     my $cnum=$env{'course.'.$cid.'.num'};
 2100:     # Retrieve discussion data for resources in course
 2101:     my %discussion_data = &Apache::lonnet::dumpstore($cid,$cdom,$cnum);
 2102: 
 2103: 
 2104:     $self->{DISCUSSION_DATA} = \%discussion_data;
 2105:     $self->{RETRIEVED_DISCUSSION_DATA} = 1;
 2106:     return $self->{DISCUSSION_DATA};
 2107: }
 2108: 
 2109: 
 2110: # Internal function: Takes a key to look up in the nav hash and implements internal
 2111: # memory caching of that key.
 2112: sub navhash {
 2113:     my $self = shift; my $key = shift;
 2114:     return $self->{NAV_HASH}->{$key};
 2115: }
 2116: 
 2117: =pod
 2118: 
 2119: =item * B<courseMapDefined>(): Returns true if the course map is defined, 
 2120:     false otherwise. Undefined course maps indicate an error somewhere in
 2121:     LON-CAPA, and you will not be able to proceed with using the navmap.
 2122:     See the B<NAV> screen for an example of using this.
 2123: 
 2124: =cut
 2125: 
 2126: # Checks to see if coursemap is defined, matching test in old lonnavmaps
 2127: sub courseMapDefined {
 2128:     my $self = shift;
 2129:     my $uri = &Apache::lonnet::clutter($env{'request.course.uri'});
 2130: 
 2131:     my $firstres = $self->navhash("map_start_$uri");
 2132:     my $lastres = $self->navhash("map_finish_$uri");
 2133:     return $firstres && $lastres;
 2134: }
 2135: 
 2136: sub getIterator {
 2137:     my $self = shift;
 2138:     my $iterator = Apache::lonnavmaps::iterator->new($self, shift, shift,
 2139:                                                      shift, undef, shift,
 2140: 						     shift, shift);
 2141:     return $iterator;
 2142: }
 2143: 
 2144: # Private method: Does the given resource (as a symb string) have
 2145: # current discussion? Returns 0 if chat/mail data not extracted.
 2146: sub hasDiscussion {
 2147:     my $self = shift;
 2148:     my $symb = shift;
 2149:     $self->generate_email_discuss_status();
 2150: 
 2151:     if (!defined($self->{DISCUSSION_TIME})) { return 0; }
 2152: 
 2153:     #return defined($self->{DISCUSSION_TIME}->{$symb});
 2154: 
 2155:     # backward compatibility (bulletin boards used to be 'wrapped')
 2156:     my $ressymb = $self->wrap_symb($symb);
 2157:     if ( defined ( $self->{LAST_READ}->{$ressymb} ) ) {
 2158:         return $self->{DISCUSSION_TIME}->{$ressymb} > $self->{LAST_READ}->{$ressymb};
 2159:     } else {
 2160: #        return $self->{DISCUSSION_TIME}->{$ressymb} >  $self->{LAST_CHECK}; # v.1.1 behavior 
 2161:         return $self->{DISCUSSION_TIME}->{$ressymb} >  0; # in 1.2 will display speech bubble icons for all items with posts until marked as read (even if read in v 1.1).
 2162:     }
 2163: }
 2164: 
 2165: sub last_post_time {
 2166:     my $self = shift;
 2167:     my $symb = shift;
 2168:     my $ressymb = $self->wrap_symb($symb);
 2169:     return $self->{DISCUSSION_TIME}->{$ressymb};
 2170: }
 2171: 
 2172: sub discussion_info {
 2173:     my $self = shift;
 2174:     my $symb = shift;
 2175:     my $filter = shift;
 2176: 
 2177:     $self->get_discussion_data();
 2178: 
 2179:     my $ressymb = $self->wrap_symb($symb);
 2180:     # keys used to store bulletinboard postings use 'unwrapped' symb. 
 2181:     my $discsymb = &escape($self->unwrap_symb($ressymb));
 2182:     my $version = $self->{DISCUSSION_DATA}{'version:'.$discsymb};
 2183:     if (!$version) { return; }
 2184: 
 2185:     my $prevread = $self->{LAST_READ}{$ressymb};
 2186: 
 2187:     my $count = 0;
 2188:     my $hiddenflag = 0;
 2189:     my $deletedflag = 0;
 2190:     my ($hidden,$deleted,%info);
 2191: 
 2192:     for (my $id=$version; $id>0; $id--) {
 2193: 	my $vkeys=$self->{DISCUSSION_DATA}{$id.':keys:'.$discsymb};
 2194: 	my @keys=split(/:/,$vkeys);
 2195: 	if (grep(/^hidden$/ ,@keys)) {
 2196: 	    if (!$hiddenflag) {
 2197: 		$hidden = $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':hidden'};
 2198: 		$hiddenflag = 1;
 2199: 	    }
 2200: 	} elsif (grep(/^deleted$/,@keys)) {
 2201: 	    if (!$deletedflag) {
 2202: 		$deleted = $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':deleted'};
 2203: 		$deletedflag = 1;
 2204: 	    }
 2205: 	} else {
 2206: 	    if (($hidden !~/\.$id\./) && ($deleted !~/\.$id\./)) {
 2207:                 if ($filter eq 'unread') {
 2208: 		    if ($prevread >= $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':timestamp'}) {
 2209:                         next;
 2210:                     }
 2211:                 }
 2212: 		$count++;
 2213: 		$info{$count}{'subject'} =
 2214: 		    $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':subject'};
 2215:                 $info{$count}{'id'} = $id;
 2216:                 $info{$count}{'timestamp'} = $self->{DISCUSSION_DATA}{$id.':'.$discsymb.':timestamp'};
 2217:             }
 2218: 	}
 2219:     }
 2220:     if (wantarray) {
 2221: 	return ($count,%info);
 2222:     }
 2223:     return $count;
 2224: }
 2225: 
 2226: sub wrap_symb {
 2227:     my $self = shift;
 2228:     my $symb = shift;
 2229:     if ($symb =~ m-___(adm/[^/]+/[^/]+/)(\d+)(/bulletinboard)$-) {
 2230:         unless ($symb =~ m|adm/wrapper/adm|) {
 2231:             $symb = 'bulletin___'.$2.'___adm/wrapper/'.$1.$2.$3;
 2232:         }
 2233:     }
 2234:     return $symb;
 2235: }
 2236: 
 2237: sub unwrap_symb {
 2238:     my $self = shift;
 2239:     my $ressymb = shift;
 2240:     my $discsymb = $ressymb;
 2241:     if ($ressymb =~ m-^(bulletin___\d+___)adm/wrapper/(adm/[^/]+/[^/]+/\d+/bulletinboard)$-) {
 2242:          $discsymb = $1.$2;
 2243:     }
 2244:     return $discsymb;
 2245: }
 2246: 
 2247: # Private method: Does the given resource (as a symb string) have
 2248: # current feedback? Returns the string in the feedback hash, which
 2249: # will be false if it does not exist.
 2250: 
 2251: sub getFeedback { 
 2252:     my $self = shift;
 2253:     my $symb = shift;
 2254:     my $source = shift;
 2255: 
 2256:     $self->generate_email_discuss_status();
 2257: 
 2258:     if (!defined($self->{FEEDBACK})) { return ""; }
 2259:     
 2260:     my $feedback;
 2261:     if ($self->{FEEDBACK}->{$symb}) {
 2262:         $feedback = $self->{FEEDBACK}->{$symb};
 2263:         if ($self->{FEEDBACK}->{$source}) {
 2264:             $feedback .= ','.$self->{FEEDBACK}->{$source};
 2265:         }
 2266:     } else {
 2267:         if ($self->{FEEDBACK}->{$source}) {
 2268:             $feedback = $self->{FEEDBACK}->{$source};
 2269:         }
 2270:     }
 2271:     return $feedback;
 2272: }
 2273: 
 2274: # Private method: Get the errors for that resource (by source).
 2275: sub getErrors { 
 2276:     my $self = shift;
 2277:     my $symb = shift;
 2278:     my $src = shift;
 2279: 
 2280:     $self->generate_email_discuss_status();
 2281: 
 2282:     if (!defined($self->{ERROR_MSG})) { return ""; }
 2283: 
 2284:     my $errors;
 2285:     if ($self->{ERROR_MSG}->{$symb}) {
 2286:         $errors = $self->{ERROR_MSG}->{$symb};
 2287:         if ($self->{ERROR_MSG}->{$src}) {
 2288:             $errors .= ','.$self->{ERROR_MSG}->{$src};
 2289:         }
 2290:     } else {
 2291:         if ($self->{ERROR_MSG}->{$src}) {
 2292:             $errors = $self->{ERROR_MSG}->{$src};
 2293:         }
 2294:     }
 2295:     return $errors;
 2296: }
 2297: 
 2298: =pod
 2299: 
 2300: =item * B<getById>(id):
 2301: 
 2302: Based on the ID of the resource (1.1, 3.2, etc.), get a resource
 2303: object for that resource. This method, or other methods that use it
 2304: (as in the resource object) is the only proper way to obtain a
 2305: resource object.
 2306: 
 2307: =item * B<getBySymb>(symb):
 2308: 
 2309: Based on the symb of the resource, get a resource object for that
 2310: resource. This is one of the proper ways to get a resource object.
 2311: 
 2312: =item * B<getByMapPc>(map_pc):
 2313: 
 2314: Based on the map_pc of the resource, get a resource object for
 2315: the given map. This is one of the proper ways to get a resource object.
 2316: 
 2317: =cut
 2318: 
 2319: # The strategy here is to cache the resource objects, and only construct them
 2320: # as we use them. The real point is to prevent reading any more from the tied
 2321: # hash than we have to, which should hopefully alleviate speed problems.
 2322: 
 2323: sub getById {
 2324:     my $self = shift;
 2325:     my $id = shift;
 2326: 
 2327:     if (defined ($self->{RESOURCE_CACHE}->{$id}))
 2328:     {
 2329:         return $self->{RESOURCE_CACHE}->{$id};
 2330:     }
 2331: 
 2332:     # resource handles inserting itself into cache.
 2333:     # Not clear why the quotes are necessary, but as of this
 2334:     # writing it doesn't work without them.
 2335:     return "Apache::lonnavmaps::resource"->new($self, $id);
 2336: }
 2337: 
 2338: sub getBySymb {
 2339:     my $self = shift;
 2340:     my $symb = shift;
 2341: 
 2342:     my ($mapUrl, $id, $filename) = &Apache::lonnet::decode_symb($symb);
 2343:     my $map = $self->getResourceByUrl($mapUrl);
 2344:     my $returnvalue = undef;
 2345:     if (ref($map)) {
 2346:         $returnvalue = $self->getById($map->map_pc() .'.'.$id);
 2347:     }
 2348:     return $returnvalue;
 2349: }
 2350: 
 2351: sub getByMapPc {
 2352:     my $self = shift;
 2353:     my $map_pc = shift;
 2354:     my $map_id = $self->{NAV_HASH}->{'map_id_' . $map_pc};
 2355:     $map_id = $self->{NAV_HASH}->{'ids_' . $map_id};
 2356:     return $self->getById($map_id);
 2357: }
 2358: 
 2359: =pod
 2360: 
 2361: =item * B<firstResource>():
 2362: 
 2363: Returns a resource object reference corresponding to the first
 2364: resource in the navmap.
 2365: 
 2366: =cut
 2367: 
 2368: sub firstResource {
 2369:     my $self = shift;
 2370:     my $firstResource = $self->navhash('map_start_' .
 2371:                      &Apache::lonnet::clutter($env{'request.course.uri'}));
 2372:     return $self->getById($firstResource);
 2373: }
 2374: 
 2375: =pod
 2376: 
 2377: =item * B<finishResource>():
 2378: 
 2379: Returns a resource object reference corresponding to the last resource
 2380: in the navmap.
 2381: 
 2382: =cut
 2383: 
 2384: sub finishResource {
 2385:     my $self = shift;
 2386:     my $firstResource = $self->navhash('map_finish_' .
 2387:                      &Apache::lonnet::clutter($env{'request.course.uri'}));
 2388:     return $self->getById($firstResource);
 2389: }
 2390: 
 2391: # Parmval reads the parm hash and cascades the lookups. parmval_real does
 2392: # the actual lookup; parmval caches the results.
 2393: sub parmval {
 2394:     my $self = shift;
 2395:     my ($what,$symb,$recurse)=@_;
 2396:     my $hashkey = $what."|||".$symb;
 2397: 
 2398:     if (defined($self->{PARM_CACHE}->{$hashkey})) {
 2399:         if (ref($self->{PARM_CACHE}->{$hashkey}) eq 'ARRAY') { 
 2400:             if (defined($self->{PARM_CACHE}->{$hashkey}->[0])) {
 2401:                 if (wantarray) {
 2402:                     return @{$self->{PARM_CACHE}->{$hashkey}};
 2403:                 } else {
 2404:                     return $self->{PARM_CACHE}->{$hashkey}->[0];
 2405:                 }
 2406:             }
 2407:         } else {
 2408:             return $self->{PARM_CACHE}->{$hashkey};
 2409:         }
 2410:     }
 2411:     my $result = $self->parmval_real($what, $symb, $recurse);
 2412:     $self->{PARM_CACHE}->{$hashkey} = $result;
 2413:     if (wantarray) {
 2414:         return @{$result};
 2415:     }
 2416:     return $result->[0];
 2417: }
 2418: 
 2419: sub parmval_real {
 2420:     my $self = shift;
 2421:     my ($what,$symb,$recurse) = @_;
 2422: 
 2423:     # Make sure the {USER_OPT} and {COURSE_OPT} hashes are populated
 2424:     $self->generate_course_user_opt();
 2425: 
 2426:     my $cid=$env{'request.course.id'};
 2427:     my $csec=$env{'request.course.sec'};
 2428:     my $cgroup='';
 2429:     my @cgrps=split(/:/,$env{'request.course.groups'});
 2430:     if (@cgrps > 0) {
 2431:         @cgrps = sort(@cgrps);
 2432:         $cgroup = $cgrps[0];
 2433:     } 
 2434:     my $uname=$env{'user.name'};
 2435:     my $udom=$env{'user.domain'};
 2436: 
 2437:     unless ($symb) { return ['']; }
 2438:     my $result='';
 2439: 
 2440:     my ($mapname,$id,$fn)=&Apache::lonnet::decode_symb($symb);
 2441:     $mapname = &Apache::lonnet::deversion($mapname);
 2442: # ----------------------------------------------------- Cascading lookup scheme
 2443:     my $rwhat=$what;
 2444:     $what=~s/^parameter\_//;
 2445:     $what=~s/\_/\./;
 2446: 
 2447:     my $symbparm=$symb.'.'.$what;
 2448:     my $mapparm=$mapname.'___(all).'.$what;
 2449:     my $usercourseprefix=$cid;
 2450: 
 2451:     my $grplevel=$usercourseprefix.'.['.$cgroup.'].'.$what;
 2452:     my $grplevelr=$usercourseprefix.'.['.$cgroup.'].'.$symbparm;
 2453:     my $grplevelm=$usercourseprefix.'.['.$cgroup.'].'.$mapparm;
 2454: 
 2455:     my $seclevel= $usercourseprefix.'.['.$csec.'].'.$what;
 2456:     my $seclevelr=$usercourseprefix.'.['.$csec.'].'.$symbparm;
 2457:     my $seclevelm=$usercourseprefix.'.['.$csec.'].'.$mapparm;
 2458: 
 2459:     my $courselevel= $usercourseprefix.'.'.$what;
 2460:     my $courselevelr=$usercourseprefix.'.'.$symbparm;
 2461:     my $courselevelm=$usercourseprefix.'.'.$mapparm;
 2462: 
 2463:     my $useropt = $self->{USER_OPT};
 2464:     my $courseopt = $self->{COURSE_OPT};
 2465:     my $parmhash = $self->{PARM_HASH};
 2466: 
 2467: # ---------------------------------------------------------- first, check user
 2468:     if ($uname and defined($useropt)) {
 2469:         if (defined($$useropt{$courselevelr})) { return [$$useropt{$courselevelr},'resource']; }
 2470:         if (defined($$useropt{$courselevelm})) { return [$$useropt{$courselevelm},'map']; }
 2471:         if (defined($$useropt{$courselevel})) { return [$$useropt{$courselevel},'course']; }
 2472:     }
 2473: 
 2474: # ------------------------------------------------------- second, check course
 2475:     if ($cgroup ne '' and defined($courseopt)) {
 2476:         if (defined($$courseopt{$grplevelr})) { return [$$courseopt{$grplevelr},'resource']; }
 2477:         if (defined($$courseopt{$grplevelm})) { return [$$courseopt{$grplevelm},'map']; }
 2478:         if (defined($$courseopt{$grplevel})) { return [$$courseopt{$grplevel},'course']; }
 2479:     }
 2480: 
 2481:     if ($csec and defined($courseopt)) {
 2482:         if (defined($$courseopt{$seclevelr})) { return [$$courseopt{$seclevelr},'resource']; }
 2483:         if (defined($$courseopt{$seclevelm})) { return [$$courseopt{$seclevelm},'map']; }
 2484:         if (defined($$courseopt{$seclevel})) { return [$$courseopt{$seclevel},'course']; }
 2485:     }
 2486: 
 2487:     if (defined($courseopt)) {
 2488:         if (defined($$courseopt{$courselevelr})) { return [$$courseopt{$courselevelr},'resource']; }
 2489:     }
 2490: 
 2491: # ----------------------------------------------------- third, check map parms
 2492: 
 2493:     my $thisparm=$$parmhash{$symbparm};
 2494:     if (defined($thisparm)) { return [$thisparm,'map']; }
 2495: 
 2496: # ----------------------------------------------------- fourth , check default
 2497: 
 2498:     my $meta_rwhat=$rwhat;
 2499:     $meta_rwhat=~s/\./_/g;
 2500:     my $default=&Apache::lonnet::metadata($fn,$meta_rwhat);
 2501:     if (defined($default)) { return [$default,'resource']}
 2502:     $default=&Apache::lonnet::metadata($fn,'parameter_'.$meta_rwhat);
 2503:     if (defined($default)) { return [$default,'resource']}
 2504: # --------------------------------------------------- fifth, check more course
 2505:     if (defined($courseopt)) {
 2506:         if (defined($$courseopt{$courselevelm})) { return [$$courseopt{$courselevelm},'map']; }
 2507:         if (defined($$courseopt{$courselevel})) {
 2508:            my $ret = [$$courseopt{$courselevel},'course'];
 2509:            return $ret;
 2510:        }
 2511:     }
 2512: # --------------------------------------------------- sixth , cascade up parts
 2513: 
 2514:     my ($space,@qualifier)=split(/\./,$rwhat);
 2515:     my $qualifier=join('.',@qualifier);
 2516:     unless ($space eq '0') {
 2517: 	my @parts=split(/_/,$space);
 2518: 	my $id=pop(@parts);
 2519: 	my $part=join('_',@parts);
 2520: 	if ($part eq '') { $part='0'; }
 2521:        my @partgeneral=$self->parmval($part.".$qualifier",$symb,1);
 2522:        if (defined($partgeneral[0])) { return \@partgeneral; }
 2523:     }
 2524:     if ($recurse) { return []; }
 2525:     my $pack_def=&Apache::lonnet::packages_tab_default($fn,'resource.'.$rwhat);
 2526:     if (defined($pack_def)) { return [$pack_def,'resource']; }
 2527:     return [''];
 2528: }
 2529: 
 2530: =pod
 2531: 
 2532: =item * B<getResourceByUrl>(url,multiple):
 2533: 
 2534: Retrieves a resource object by URL of the resource, unless the optional
 2535: multiple parameter is included in which case an array of resource 
 2536: objects is returned. If passed a resource object, it will simply return  
 2537: it, so it is safe to use this method in code like
 2538: "$res = $navmap->getResourceByUrl($res)"
 2539: if you're not sure if $res is already an object, or just a URL. If the
 2540: resource appears multiple times in the course, only the first instance 
 2541: will be returned (useful for maps), unless the multiple parameter has
 2542: been included, in which case all instances are returned in an array.
 2543: 
 2544: =item * B<retrieveResources>(map, filterFunc, recursive, bailout, showall):
 2545: 
 2546: The map is a specification of a map to retreive the resources from,
 2547: either as a url or as an object. The filterFunc is a reference to a
 2548: function that takes a resource object as its one argument and returns
 2549: true if the resource should be included, or false if it should not
 2550: be. If recursive is true, the map will be recursively examined,
 2551: otherwise it will not be. If bailout is true, the function will return
 2552: as soon as it finds a resource, if false it will finish. If showall is
 2553: true it will not hide maps that contain nothing but one other map. By
 2554: default, the map is the top-level map of the course, filterFunc is a
 2555: function that always returns 1, recursive is true, bailout is false,
 2556: showall is false. The resources will be returned in a list containing
 2557: the resource objects for the corresponding resources, with B<no
 2558: structure information> in the list; regardless of branching,
 2559: recursion, etc., it will be a flat list.
 2560: 
 2561: Thus, this is suitable for cases where you don't want the structure,
 2562: just a list of all resources. It is also suitable for finding out how
 2563: many resources match a given description; for this use, if all you
 2564: want to know is if I<any> resources match the description, the bailout
 2565: parameter will allow you to avoid potentially expensive enumeration of
 2566: all matching resources.
 2567: 
 2568: =item * B<hasResource>(map, filterFunc, recursive, showall):
 2569: 
 2570: Convenience method for
 2571: 
 2572:  scalar(retrieveResources($map, $filterFunc, $recursive, 1, $showall)) > 0
 2573: 
 2574: which will tell whether the map has resources matching the description
 2575: in the filter function.
 2576: 
 2577: =item * B<usedVersion>(url):
 2578: 
 2579: Retrieves version infomation for a url. Returns the version (a number, or 
 2580: the string "mostrecent") for resources which have version information in  
 2581: the big hash.
 2582: 
 2583: =cut
 2584: 
 2585: 
 2586: sub getResourceByUrl {
 2587:     my $self = shift;
 2588:     my $resUrl = shift;
 2589:     my $multiple = shift;
 2590: 
 2591:     if (ref($resUrl)) { return $resUrl; }
 2592: 
 2593:     $resUrl = &Apache::lonnet::clutter($resUrl);
 2594:     my $resId = $self->{NAV_HASH}->{'ids_' . $resUrl};
 2595:     if (!$resId) { return ''; }
 2596:     if ($multiple) {
 2597:         my @resources = ();
 2598:         my @resIds = split (/,/, $resId);
 2599:         foreach my $id (@resIds) {
 2600:             my $resourceId = $self->getById($id);
 2601:             if ($resourceId) { 
 2602:                 push(@resources,$resourceId);
 2603:             }
 2604:         }
 2605:         return @resources;
 2606:     } else {
 2607:         if ($resId =~ /,/) {
 2608:             $resId = (split (/,/, $resId))[0];
 2609:         }
 2610:         return $self->getById($resId);
 2611:     }
 2612: }
 2613: 
 2614: sub retrieveResources {
 2615:     my $self = shift;
 2616:     my $map = shift;
 2617:     my $filterFunc = shift;
 2618:     if (!defined ($filterFunc)) {
 2619:         $filterFunc = sub {return 1;};
 2620:     }
 2621:     my $recursive = shift;
 2622:     if (!defined($recursive)) { $recursive = 1; }
 2623:     my $bailout = shift;
 2624:     if (!defined($bailout)) { $bailout = 0; }
 2625:     my $showall = shift;
 2626:     # Create the necessary iterator.
 2627:     if (!ref($map)) { # assume it's a url of a map.
 2628:         $map = $self->getResourceByUrl($map);
 2629:     }
 2630: 
 2631:     # If nothing was passed, assume top-level map
 2632:     if (!$map) {
 2633: 	$map = $self->getById('0.0');
 2634:     }
 2635: 
 2636:     # Check the map's validity.
 2637:     if (!$map->is_map()) {
 2638:         # Oh, to throw an exception.... how I'd love that!
 2639:         return ();
 2640:     }
 2641: 
 2642:     # Get an iterator.
 2643:     my $it = $self->getIterator($map->map_start(), $map->map_finish(),
 2644:                                 undef, $recursive, $showall);
 2645: 
 2646:     my @resources = ();
 2647: 
 2648:     if (&$filterFunc($map)) {
 2649: 	push(@resources, $map);
 2650:     }
 2651: 
 2652:     # Run down the iterator and collect the resources.
 2653:     my $curRes;
 2654: 
 2655:     while ($curRes = $it->next()) {
 2656:         if (ref($curRes)) {
 2657:             if (!&$filterFunc($curRes)) {
 2658:                 next;
 2659:             }
 2660: 
 2661:             push(@resources, $curRes);
 2662: 
 2663:             if ($bailout) {
 2664:                 return @resources;
 2665:             }
 2666:         }
 2667: 
 2668:     }
 2669: 
 2670:     return @resources;
 2671: }
 2672: 
 2673: sub hasResource {
 2674:     my $self = shift;
 2675:     my $map = shift;
 2676:     my $filterFunc = shift;
 2677:     my $recursive = shift;
 2678:     my $showall = shift;
 2679:     
 2680:     return scalar($self->retrieveResources($map, $filterFunc, $recursive, 1, $showall)) > 0;
 2681: }
 2682: 
 2683: sub usedVersion {
 2684:     my $self = shift;
 2685:     my $linkurl = shift;
 2686:     return $self->navhash("version_$linkurl");
 2687: }
 2688: 
 2689: 1;
 2690: 
 2691: package Apache::lonnavmaps::iterator;
 2692: use Scalar::Util qw(weaken);
 2693: use Apache::lonnet;
 2694: 
 2695: =pod
 2696: 
 2697: =back
 2698: 
 2699: =head1 Object: navmap Iterator
 2700: 
 2701: An I<iterator> encapsulates the logic required to traverse a data
 2702: structure. navmap uses an iterator to traverse the course map
 2703: according to the criteria you wish to use.
 2704: 
 2705: To obtain an iterator, call the B<getIterator>() function of a
 2706: B<navmap> object. (Do not instantiate Apache::lonnavmaps::iterator
 2707: directly.) This will return a reference to the iterator:
 2708: 
 2709: C<my $resourceIterator = $navmap-E<gt>getIterator();>
 2710: 
 2711: To get the next thing from the iterator, call B<next>:
 2712: 
 2713: C<my $nextThing = $resourceIterator-E<gt>next()>
 2714: 
 2715: getIterator behaves as follows:
 2716: 
 2717: =over 4
 2718: 
 2719: =item * B<getIterator>(firstResource, finishResource, filterHash, condition, forceTop, returnTopMap):
 2720: 
 2721: All parameters are optional. firstResource is a resource reference
 2722: corresponding to where the iterator should start. It defaults to
 2723: navmap->firstResource() for the corresponding nav map. finishResource
 2724: corresponds to where you want the iterator to end, defaulting to
 2725: navmap->finishResource(). filterHash is a hash used as a set
 2726: containing strings representing the resource IDs, defaulting to
 2727: empty. Condition is a 1 or 0 that sets what to do with the filter
 2728: hash: If a 0, then only resources that exist IN the filterHash will be
 2729: recursed on. If it is a 1, only resources NOT in the filterHash will
 2730: be recursed on. Defaults to 0. forceTop is a boolean value. If it is
 2731: false (default), the iterator will only return the first level of map
 2732: that is not just a single, 'redirecting' map. If true, the iterator
 2733: will return all information, starting with the top-level map,
 2734: regardless of content. returnTopMap, if true (default false), will
 2735: cause the iterator to return the top-level map object (resource 0.0)
 2736: before anything else.
 2737: 
 2738: Thus, by default, only top-level resources will be shown. Change the
 2739: condition to a 1 without changing the hash, and all resources will be
 2740: shown. Changing the condition to 1 and including some values in the
 2741: hash will allow you to selectively suppress parts of the navmap, while
 2742: leaving it on 0 and adding things to the hash will allow you to
 2743: selectively add parts of the nav map. See the handler code for
 2744: examples.
 2745: 
 2746: The iterator will return either a reference to a resource object, or a
 2747: token representing something in the map, such as the beginning of a
 2748: new branch. The possible tokens are:
 2749: 
 2750: =over 4
 2751: 
 2752: =item * B<END_ITERATOR>:
 2753: 
 2754: The iterator has returned all that it's going to. Further calls to the
 2755: iterator will just produce more of these. This is a "false" value, and
 2756: is the only false value the iterator which will be returned, so it can
 2757: be used as a loop sentinel.
 2758: 
 2759: =item * B<BEGIN_MAP>:
 2760: 
 2761: A new map is being recursed into. This is returned I<after> the map
 2762: resource itself is returned.
 2763: 
 2764: =item * B<END_MAP>:
 2765: 
 2766: The map is now done.
 2767: 
 2768: =item * B<BEGIN_BRANCH>:
 2769: 
 2770: A branch is now starting. The next resource returned will be the first
 2771: in that branch.
 2772: 
 2773: =item * B<END_BRANCH>:
 2774: 
 2775: The branch is now done.
 2776: 
 2777: =back
 2778: 
 2779: The tokens are retreivable via methods on the iterator object, i.e.,
 2780: $iterator->END_MAP.
 2781: 
 2782: Maps can contain empty resources. The iterator will automatically skip
 2783: over such resources, but will still treat the structure
 2784: correctly. Thus, a complicated map with several branches, but
 2785: consisting entirely of empty resources except for one beginning or
 2786: ending resource, will cause a lot of BRANCH_STARTs and BRANCH_ENDs,
 2787: but only one resource will be returned.
 2788: 
 2789: =back
 2790: 
 2791: =head2 Normal Usage
 2792: 
 2793: Normal usage of the iterator object is to do the following:
 2794: 
 2795:  my $it = $navmap->getIterator([your params here]);
 2796:  my $curRes;
 2797:  while ($curRes = $it->next()) {
 2798:    [your logic here]
 2799:  }
 2800: 
 2801: Note that inside of the loop, it's frequently useful to check if
 2802: "$curRes" is a reference or not with the reference function; only
 2803: resource objects will be references, and any non-references will 
 2804: be the tokens described above.
 2805: 
 2806: Also note there is some old code floating around that trys to track
 2807: the depth of the iterator to see when it's done; do not copy that 
 2808: code. It is difficult to get right and harder to understand than
 2809: this. They should be migrated to this new style.
 2810: 
 2811: =cut
 2812: 
 2813: # Here are the tokens for the iterator:
 2814: 
 2815: sub END_ITERATOR { return 0; }
 2816: sub BEGIN_MAP { return 1; }    # begining of a new map
 2817: sub END_MAP { return 2; }      # end of the map
 2818: sub BEGIN_BRANCH { return 3; } # beginning of a branch
 2819: sub END_BRANCH { return 4; }   # end of a branch
 2820: sub FORWARD { return 1; }      # go forward
 2821: sub BACKWARD { return 2; }
 2822: 
 2823: sub min {
 2824:     (my $a, my $b) = @_;
 2825:     if ($a < $b) { return $a; } else { return $b; }
 2826: }
 2827: 
 2828: sub new {
 2829:     # magic invocation to create a class instance
 2830:     my $proto = shift;
 2831:     my $class = ref($proto) || $proto;
 2832:     my $self = {};
 2833: 
 2834:     weaken($self->{NAV_MAP} = shift);
 2835:     return undef unless ($self->{NAV_MAP});
 2836: 
 2837:     # Handle the parameters
 2838:     $self->{FIRST_RESOURCE} = shift || $self->{NAV_MAP}->firstResource();
 2839:     $self->{FINISH_RESOURCE} = shift || $self->{NAV_MAP}->finishResource();
 2840: 
 2841:     # If the given resources are just the ID of the resource, get the
 2842:     # objects
 2843:     if (!ref($self->{FIRST_RESOURCE})) { $self->{FIRST_RESOURCE} = 
 2844:              $self->{NAV_MAP}->getById($self->{FIRST_RESOURCE}); }
 2845:     if (!ref($self->{FINISH_RESOURCE})) { $self->{FINISH_RESOURCE} = 
 2846:              $self->{NAV_MAP}->getById($self->{FINISH_RESOURCE}); }
 2847: 
 2848:     $self->{FILTER} = shift;
 2849: 
 2850:     # A hash, used as a set, of resource already seen
 2851:     $self->{ALREADY_SEEN} = shift;
 2852:     if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };
 2853:     $self->{CONDITION} = shift;
 2854: 
 2855:     # Do we want to automatically follow "redirection" maps?
 2856:     $self->{FORCE_TOP} = shift;
 2857: 
 2858:     # Do we want to return the top-level map object (resource 0.0)?
 2859:     $self->{RETURN_0} = shift;
 2860:     # have we done that yet?
 2861:     $self->{HAVE_RETURNED_0} = 0;
 2862: 
 2863:     # Now, we need to pre-process the map, by walking forward and backward
 2864:     # over the parts of the map we're going to look at.
 2865: 
 2866:     # The processing steps are exactly the same, except for a few small 
 2867:     # changes, so I bundle those up in the following list of two elements:
 2868:     # (direction_to_iterate, VAL_name, next_resource_method_to_call,
 2869:     # first_resource).
 2870:     # This prevents writing nearly-identical code twice.
 2871:     my @iterations = ( [FORWARD(), 'TOP_DOWN_VAL', 'getNext', 
 2872:                         'FIRST_RESOURCE'],
 2873:                        [BACKWARD(), 'BOT_UP_VAL', 'getPrevious', 
 2874:                         'FINISH_RESOURCE'] );
 2875: 
 2876:     my $maxDepth = 0; # tracks max depth
 2877: 
 2878:     # If there is only one resource in this map, and it's a map, we
 2879:     # want to remember that, so the user can ask for the first map
 2880:     # that isn't just a redirector.
 2881:     my $resource; my $resourceCount = 0;
 2882: 
 2883:     # Documentation on this algorithm can be found in the CVS repository at 
 2884:     # /docs/lonnavdocs; these "**#**" markers correspond to documentation
 2885:     # in that file.
 2886:     # **1**
 2887: 
 2888:     foreach my $pass (@iterations) {
 2889:         my $direction = $pass->[0];
 2890:         my $valName = $pass->[1];
 2891:         my $nextResourceMethod = $pass->[2];
 2892:         my $firstResourceName = $pass->[3];
 2893: 
 2894:         my $iterator = Apache::lonnavmaps::DFSiterator->new($self->{NAV_MAP}, 
 2895:                                                             $self->{FIRST_RESOURCE},
 2896:                                                             $self->{FINISH_RESOURCE},
 2897:                                                             {}, undef, 0, $direction);
 2898:     
 2899:         # prime the recursion
 2900:         $self->{$firstResourceName}->{DATA}->{$valName} = 0;
 2901: 	$iterator->next();
 2902:         my $curRes = $iterator->next();
 2903: 	my $depth = 1;
 2904:         while ($depth > 0) {
 2905: 	    if ($curRes == $iterator->BEGIN_MAP()) { $depth++; }
 2906: 	    if ($curRes == $iterator->END_MAP()) { $depth--; }
 2907: 
 2908:             if (ref($curRes)) {
 2909:                 # If there's only one resource, this will save it
 2910:                 # we have to filter empty resources from consideration here,
 2911:                 # or even "empty", redirecting maps have two (start & finish)
 2912:                 # or three (start, finish, plus redirector)
 2913:                 if($direction == FORWARD && $curRes->src()) { 
 2914:                     $resource = $curRes; $resourceCount++; 
 2915:                 }
 2916:                 my $resultingVal = $curRes->{DATA}->{$valName};
 2917:                 my $nextResources = $curRes->$nextResourceMethod();
 2918:                 my $nextCount = scalar(@{$nextResources});
 2919: 
 2920:                 if ($nextCount == 1) { # **3**
 2921:                     my $current = $nextResources->[0]->{DATA}->{$valName} || 999999999;
 2922:                     $nextResources->[0]->{DATA}->{$valName} = min($resultingVal, $current);
 2923:                 }
 2924:                 
 2925:                 if ($nextCount > 1) { # **4**
 2926:                     foreach my $res (@{$nextResources}) {
 2927:                         my $current = $res->{DATA}->{$valName} || 999999999;
 2928:                         $res->{DATA}->{$valName} = min($current, $resultingVal + 1);
 2929:                     }
 2930:                 }
 2931:             }
 2932:             
 2933:             # Assign the final val (**2**)
 2934:             if (ref($curRes) && $direction == BACKWARD()) {
 2935:                 my $finalDepth = min($curRes->{DATA}->{TOP_DOWN_VAL},
 2936:                                      $curRes->{DATA}->{BOT_UP_VAL});
 2937:                 
 2938:                 $curRes->{DATA}->{DISPLAY_DEPTH} = $finalDepth;
 2939:                 if ($finalDepth > $maxDepth) {$maxDepth = $finalDepth;}
 2940:             }
 2941: 
 2942: 	    $curRes = $iterator->next();
 2943:         }
 2944:     }
 2945: 
 2946:     # Check: Was this only one resource, a map?
 2947:     if ($resourceCount == 1 && $resource->is_sequence() && !$self->{FORCE_TOP}) { 
 2948:         my $firstResource = $resource->map_start();
 2949:         my $finishResource = $resource->map_finish();
 2950:         return 
 2951:             Apache::lonnavmaps::iterator->new($self->{NAV_MAP}, $firstResource,
 2952:                                               $finishResource, $self->{FILTER},
 2953:                                               $self->{ALREADY_SEEN}, 
 2954:                                               $self->{CONDITION},
 2955: 					      $self->{FORCE_TOP});
 2956:         
 2957:     }
 2958: 
 2959:     # Set up some bookkeeping information.
 2960:     $self->{CURRENT_DEPTH} = 0;
 2961:     $self->{MAX_DEPTH} = $maxDepth;
 2962:     $self->{STACK} = [];
 2963:     $self->{RECURSIVE_ITERATOR_FLAG} = 0;
 2964:     $self->{FINISHED} = 0; # When true, the iterator has finished
 2965: 
 2966:     for (my $i = 0; $i <= $self->{MAX_DEPTH}; $i++) {
 2967:         push @{$self->{STACK}}, [];
 2968:     }
 2969: 
 2970:     # Prime the recursion w/ the first resource **5**
 2971:     push @{$self->{STACK}->[0]}, $self->{FIRST_RESOURCE};
 2972:     $self->{ALREADY_SEEN}->{$self->{FIRST_RESOURCE}->{ID}} = 1;
 2973: 
 2974:     bless ($self);
 2975: 
 2976:     return $self;
 2977: }
 2978: 
 2979: sub next {
 2980:     my $self = shift;
 2981:     my $closeAllPages=shift;
 2982:     if ($self->{FINISHED}) {
 2983: 	return END_ITERATOR();
 2984:     }
 2985: 
 2986:     # If we want to return the top-level map object, and haven't yet,
 2987:     # do so.
 2988:     if ($self->{RETURN_0} && !$self->{HAVE_RETURNED_0}) {
 2989:         $self->{HAVE_RETURNED_0} = 1;
 2990:         return $self->{NAV_MAP}->getById('0.0');
 2991:     }
 2992:     if ($self->{RETURN_0} && !$self->{HAVE_RETURNED_0_BEGIN_MAP}) {
 2993: 	$self->{HAVE_RETURNED_0_BEGIN_MAP} = 1;
 2994: 	return $self->BEGIN_MAP();
 2995:     }
 2996: 
 2997:     if ($self->{RECURSIVE_ITERATOR_FLAG}) {
 2998:         # grab the next from the recursive iterator 
 2999:         my $next = $self->{RECURSIVE_ITERATOR}->next($closeAllPages);
 3000: 
 3001:         # is it a begin or end map? If so, update the depth
 3002:         if ($next == BEGIN_MAP() ) { $self->{RECURSIVE_DEPTH}++; }
 3003:         if ($next == END_MAP() ) { $self->{RECURSIVE_DEPTH}--; }
 3004: 
 3005:         # Are we back at depth 0? If so, stop recursing
 3006:         if ($self->{RECURSIVE_DEPTH} == 0) {
 3007:             $self->{RECURSIVE_ITERATOR_FLAG} = 0;
 3008:         }
 3009: 
 3010:         return $next;
 3011:     }
 3012: 
 3013:     if (defined($self->{FORCE_NEXT})) {
 3014:         my $tmp = $self->{FORCE_NEXT};
 3015:         $self->{FORCE_NEXT} = undef;
 3016:         return $tmp;
 3017:     }
 3018: 
 3019:     # Have we not yet begun? If not, return BEGIN_MAP and
 3020:     # remember we've started.
 3021:     if ( !$self->{STARTED} ) { 
 3022:         $self->{STARTED} = 1;
 3023:         return $self->BEGIN_MAP();
 3024:     }
 3025: 
 3026:     # Here's the guts of the iterator.
 3027:     
 3028:     # Find the next resource, if any.
 3029:     my $found = 0;
 3030:     my $i = $self->{MAX_DEPTH};
 3031:     my $newDepth;
 3032:     my $here;
 3033:     while ( $i >= 0 && !$found ) {
 3034:         if ( scalar(@{$self->{STACK}->[$i]}) > 0 ) { # **6**
 3035:             $here = pop @{$self->{STACK}->[$i]}; # **7**
 3036:             $found = 1;
 3037:             $newDepth = $i;
 3038:         }
 3039:         $i--;
 3040:     }
 3041: 
 3042:     # If we still didn't find anything, we're done.
 3043:     if ( !$found ) {
 3044:         # We need to get back down to the correct branch depth
 3045:         if ( $self->{CURRENT_DEPTH} > 0 ) {
 3046:             $self->{CURRENT_DEPTH}--;
 3047:             return END_BRANCH();
 3048:         } else {
 3049: 	    $self->{FINISHED} = 1;
 3050:             return END_MAP();
 3051:         }
 3052:     }
 3053: 
 3054:     # If this is not a resource, it must be an END_BRANCH marker we want
 3055:     # to return directly.
 3056:     if (!ref($here)) { # **8**
 3057:         if ($here == END_BRANCH()) { # paranoia, in case of later extension
 3058:             $self->{CURRENT_DEPTH}--;
 3059:             return $here;
 3060:         }
 3061:     }
 3062: 
 3063:     # Otherwise, it is a resource and it's safe to store in $self->{HERE}
 3064:     $self->{HERE} = $here;
 3065: 
 3066:     # Get to the right level
 3067:     if ( $self->{CURRENT_DEPTH} > $newDepth ) {
 3068:         push @{$self->{STACK}->[$newDepth]}, $here;
 3069:         $self->{CURRENT_DEPTH}--;
 3070:         return END_BRANCH();
 3071:     }
 3072:     if ( $self->{CURRENT_DEPTH} < $newDepth) {
 3073:         push @{$self->{STACK}->[$newDepth]}, $here;
 3074:         $self->{CURRENT_DEPTH}++;
 3075:         return BEGIN_BRANCH();
 3076:     }
 3077: 
 3078:     # If we made it here, we have the next resource, and we're at the
 3079:     # right branch level. So let's examine the resource for where
 3080:     # we can get to from here.
 3081: 
 3082:     # So we need to look at all the resources we can get to from here,
 3083:     # categorize them if we haven't seen them, remember if we have a new
 3084:     my $nextUnfiltered = $here->getNext();
 3085:     my $maxDepthAdded = -1;
 3086:     
 3087:     for (@$nextUnfiltered) {
 3088:         if (!defined($self->{ALREADY_SEEN}->{$_->{ID}})) {
 3089:             my $depth = $_->{DATA}->{DISPLAY_DEPTH};
 3090:             push @{$self->{STACK}->[$depth]}, $_;
 3091:             $self->{ALREADY_SEEN}->{$_->{ID}} = 1;
 3092:             if ($maxDepthAdded < $depth) { $maxDepthAdded = $depth; }
 3093:         }
 3094:     }
 3095: 
 3096:     # Is this the end of a branch? If so, all of the resources examined above
 3097:     # led to lower levels than the one we are currently at, so we push a END_BRANCH
 3098:     # marker onto the stack so we don't forget.
 3099:     # Example: For the usual A(BC)(DE)F case, when the iterator goes down the
 3100:     # BC branch and gets to C, it will see F as the only next resource, but it's
 3101:     # one level lower. Thus, this is the end of the branch, since there are no
 3102:     # more resources added to this level or above.
 3103:     # We don't do this if the examined resource is the finish resource,
 3104:     # because the condition given above is true, but the "END_MAP" will
 3105:     # take care of things and we should already be at depth 0.
 3106:     my $isEndOfBranch = $maxDepthAdded < $self->{CURRENT_DEPTH};
 3107:     if ($isEndOfBranch && $here != $self->{FINISH_RESOURCE}) { # **9**
 3108:         push @{$self->{STACK}->[$self->{CURRENT_DEPTH}]}, END_BRANCH();
 3109:     }
 3110: 
 3111:     # That ends the main iterator logic. Now, do we want to recurse
 3112:     # down this map (if this resource is a map)?
 3113:     if ( ($self->{HERE}->is_sequence() || (!$closeAllPages && $self->{HERE}->is_page())) &&
 3114:         (defined($self->{FILTER}->{$self->{HERE}->map_pc()}) xor $self->{CONDITION})) {
 3115:         $self->{RECURSIVE_ITERATOR_FLAG} = 1;
 3116:         my $firstResource = $self->{HERE}->map_start();
 3117:         my $finishResource = $self->{HERE}->map_finish();
 3118: 
 3119:         $self->{RECURSIVE_ITERATOR} = 
 3120:             Apache::lonnavmaps::iterator->new($self->{NAV_MAP}, $firstResource,
 3121:                                               $finishResource, $self->{FILTER},
 3122:                                               $self->{ALREADY_SEEN},
 3123: 					      $self->{CONDITION},
 3124: 					      $self->{FORCE_TOP});
 3125:     }
 3126: 
 3127:     # If this is a blank resource, don't actually return it.
 3128:     # Should you ever find you need it, make sure to add an option to the code
 3129:     #  that you can use; other things depend on this behavior.
 3130:     my $browsePriv = $self->{HERE}->browsePriv();
 3131:     if (!$self->{HERE}->src() || 
 3132:         (!($browsePriv eq 'F') && !($browsePriv eq '2')) ) {
 3133:         return $self->next($closeAllPages);
 3134:     }
 3135: 
 3136:     return $self->{HERE};
 3137: 
 3138: }
 3139: 
 3140: =pod
 3141: 
 3142: The other method available on the iterator is B<getStack>, which
 3143: returns an array populated with the current 'stack' of maps, as
 3144: references to the resource objects. Example: This is useful when
 3145: making the navigation map, as we need to check whether we are under a
 3146: page map to see if we need to link directly to the resource, or to the
 3147: page. The first elements in the array will correspond to the top of
 3148: the stack (most inclusive map).
 3149: 
 3150: =cut
 3151: 
 3152: sub getStack {
 3153:     my $self=shift;
 3154: 
 3155:     my @stack;
 3156: 
 3157:     $self->populateStack(\@stack);
 3158: 
 3159:     return \@stack;
 3160: }
 3161: 
 3162: # Private method: Calls the iterators recursively to populate the stack.
 3163: sub populateStack {
 3164:     my $self=shift;
 3165:     my $stack = shift;
 3166: 
 3167:     push @$stack, $self->{HERE} if ($self->{HERE});
 3168: 
 3169:     if ($self->{RECURSIVE_ITERATOR_FLAG}) {
 3170:         $self->{RECURSIVE_ITERATOR}->populateStack($stack);
 3171:     }
 3172: }
 3173: 
 3174: 1;
 3175: 
 3176: package Apache::lonnavmaps::DFSiterator;
 3177: use Scalar::Util qw(weaken);
 3178: use Apache::lonnet;
 3179: 
 3180: # Not documented in the perldoc: This is a simple iterator that just walks
 3181: #  through the nav map and presents the resources in a depth-first search
 3182: #  fashion, ignorant of conditionals, randomized resources, etc. It presents
 3183: #  BEGIN_MAP and END_MAP, but does not understand branches at all. It is
 3184: #  useful for pre-processing of some kind, and is in fact used by the main
 3185: #  iterator that way, but that's about it.
 3186: # One could imagine merging this into the init routine of the main iterator,
 3187: #  but this might as well be left separate, since it is possible some other
 3188: #  use might be found for it. - Jeremy
 3189: 
 3190: # Unlike the main iterator, this DOES return all resources, even blank ones.
 3191: #  The main iterator needs them to correctly preprocess the map.
 3192: 
 3193: sub BEGIN_MAP { return 1; }    # begining of a new map
 3194: sub END_MAP { return 2; }      # end of the map
 3195: sub FORWARD { return 1; }      # go forward
 3196: sub BACKWARD { return 2; }
 3197: 
 3198: # Params: Nav map ref, first resource id/ref, finish resource id/ref,
 3199: #         filter hash ref (or undef), already seen hash or undef, condition
 3200: #         (as in main iterator), direction FORWARD or BACKWARD (undef->forward).
 3201: sub new {
 3202:     # magic invocation to create a class instance
 3203:     my $proto = shift;
 3204:     my $class = ref($proto) || $proto;
 3205:     my $self = {};
 3206: 
 3207:     weaken($self->{NAV_MAP} = shift);
 3208:     return undef unless ($self->{NAV_MAP});
 3209: 
 3210:     $self->{FIRST_RESOURCE} = shift || $self->{NAV_MAP}->firstResource();
 3211:     $self->{FINISH_RESOURCE} = shift || $self->{NAV_MAP}->finishResource();
 3212: 
 3213:     # If the given resources are just the ID of the resource, get the
 3214:     # objects
 3215:     if (!ref($self->{FIRST_RESOURCE})) { $self->{FIRST_RESOURCE} = 
 3216:              $self->{NAV_MAP}->getById($self->{FIRST_RESOURCE}); }
 3217:     if (!ref($self->{FINISH_RESOURCE})) { $self->{FINISH_RESOURCE} = 
 3218:              $self->{NAV_MAP}->getById($self->{FINISH_RESOURCE}); }
 3219: 
 3220:     $self->{FILTER} = shift;
 3221: 
 3222:     # A hash, used as a set, of resource already seen
 3223:     $self->{ALREADY_SEEN} = shift;
 3224:      if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };
 3225:     $self->{CONDITION} = shift;
 3226:     $self->{DIRECTION} = shift || FORWARD();
 3227: 
 3228:     # Flag: Have we started yet?
 3229:     $self->{STARTED} = 0;
 3230: 
 3231:     # Should we continue calling the recursive iterator, if any?
 3232:     $self->{RECURSIVE_ITERATOR_FLAG} = 0;
 3233:     # The recursive iterator, if any
 3234:     $self->{RECURSIVE_ITERATOR} = undef;
 3235:     # Are we recursing on a map, or a branch?
 3236:     $self->{RECURSIVE_MAP} = 1; # we'll manually unset this when recursing on branches
 3237:     # And the count of how deep it is, so that this iterator can keep track of
 3238:     # when to pick back up again.
 3239:     $self->{RECURSIVE_DEPTH} = 0;
 3240: 
 3241:     # For keeping track of our branches, we maintain our own stack
 3242:     $self->{STACK} = [];
 3243: 
 3244:     # Start with the first resource
 3245:     if ($self->{DIRECTION} == FORWARD) {
 3246:         push @{$self->{STACK}}, $self->{FIRST_RESOURCE};
 3247:     } else {
 3248:         push @{$self->{STACK}}, $self->{FINISH_RESOURCE};
 3249:     }
 3250: 
 3251:     bless($self);
 3252:     return $self;
 3253: }
 3254: 
 3255: sub next {
 3256:     my $self = shift;
 3257:     
 3258:     # Are we using a recursive iterator? If so, pull from that and
 3259:     # watch the depth; we want to resume our level at the correct time.
 3260:     if ($self->{RECURSIVE_ITERATOR_FLAG}) {
 3261:         # grab the next from the recursive iterator
 3262:         my $next = $self->{RECURSIVE_ITERATOR}->next();
 3263:         
 3264:         # is it a begin or end map? Update depth if so
 3265:         if ($next == BEGIN_MAP() ) { $self->{RECURSIVE_DEPTH}++; }
 3266:         if ($next == END_MAP() ) { $self->{RECURSIVE_DEPTH}--; }
 3267: 
 3268:         # Are we back at depth 0? If so, stop recursing.
 3269:         if ($self->{RECURSIVE_DEPTH} == 0) {
 3270:             $self->{RECURSIVE_ITERATOR_FLAG} = 0;
 3271:         }
 3272:         
 3273:         return $next;
 3274:     }
 3275: 
 3276:     # Is there a current resource to grab? If not, then return
 3277:     # END_MAP, which will end the iterator.
 3278:     if (scalar(@{$self->{STACK}}) == 0) {
 3279:         return $self->END_MAP();
 3280:     }
 3281: 
 3282:     # Have we not yet begun? If not, return BEGIN_MAP and 
 3283:     # remember that we've started.
 3284:     if ( !$self->{STARTED} ) {
 3285:         $self->{STARTED} = 1;
 3286:         return $self->BEGIN_MAP;
 3287:     }
 3288: 
 3289:     # Get the next resource in the branch
 3290:     $self->{HERE} = pop @{$self->{STACK}};
 3291: 
 3292:     # remember that we've seen this, so we don't return it again later
 3293:     $self->{ALREADY_SEEN}->{$self->{HERE}->{ID}} = 1;
 3294:     
 3295:     # Get the next possible resources
 3296:     my $nextUnfiltered;
 3297:     if ($self->{DIRECTION} == FORWARD()) {
 3298:         $nextUnfiltered = $self->{HERE}->getNext();
 3299:     } else {
 3300:         $nextUnfiltered = $self->{HERE}->getPrevious();
 3301:     }
 3302:     my $next = [];
 3303: 
 3304:     # filter the next possibilities to remove things we've 
 3305:     # already seen.
 3306:     foreach my $item (@$nextUnfiltered) {
 3307:         if (!defined($self->{ALREADY_SEEN}->{$item->{ID}})) {
 3308:             push @$next, $item;
 3309:         }
 3310:     }
 3311: 
 3312:     while (@$next) {
 3313:         # copy the next possibilities over to the stack
 3314:         push @{$self->{STACK}}, shift @$next;
 3315:     }
 3316: 
 3317:     # If this is a map and we want to recurse down it... (not filtered out)
 3318:     if ($self->{HERE}->is_map() && 
 3319:          (defined($self->{FILTER}->{$self->{HERE}->map_pc()}) xor $self->{CONDITION})) { 
 3320:         $self->{RECURSIVE_ITERATOR_FLAG} = 1;
 3321:         my $firstResource = $self->{HERE}->map_start();
 3322:         my $finishResource = $self->{HERE}->map_finish();
 3323: 
 3324:         $self->{RECURSIVE_ITERATOR} =
 3325:           Apache::lonnavmaps::DFSiterator->new ($self->{NAV_MAP}, $firstResource, 
 3326:                      $finishResource, $self->{FILTER}, $self->{ALREADY_SEEN},
 3327:                                              $self->{CONDITION}, $self->{DIRECTION});
 3328:     }
 3329: 
 3330:     return $self->{HERE};
 3331: }
 3332: 
 3333: # Identical to the full iterator methods of the same name. Hate to copy/paste
 3334: # but I also hate to "inherit" either iterator from the other.
 3335: 
 3336: sub getStack {
 3337:     my $self=shift;
 3338: 
 3339:     my @stack;
 3340: 
 3341:     $self->populateStack(\@stack);
 3342: 
 3343:     return \@stack;
 3344: }
 3345: 
 3346: # Private method: Calls the iterators recursively to populate the stack.
 3347: sub populateStack {
 3348:     my $self=shift;
 3349:     my $stack = shift;
 3350: 
 3351:     push @$stack, $self->{HERE} if ($self->{HERE});
 3352: 
 3353:     if ($self->{RECURSIVE_ITERATOR_FLAG}) {
 3354:         $self->{RECURSIVE_ITERATOR}->populateStack($stack);
 3355:     }
 3356: }
 3357: 
 3358: 1;
 3359: 
 3360: package Apache::lonnavmaps::resource;
 3361: use Scalar::Util qw(weaken);
 3362: use Apache::lonnet;
 3363: 
 3364: =pod
 3365: 
 3366: =head1 Object: resource 
 3367: 
 3368: X<resource, navmap object>
 3369: A resource object encapsulates a resource in a resource map, allowing
 3370: easy manipulation of the resource, querying the properties of the
 3371: resource (including user properties), and represents a reference that
 3372: can be used as the canonical representation of the resource by
 3373: lonnavmap clients like renderers.
 3374: 
 3375: A resource only makes sense in the context of a navmap, as some of the
 3376: data is stored in the navmap object.
 3377: 
 3378: You will probably never need to instantiate this object directly. Use
 3379: Apache::lonnavmaps::navmap, and use the "start" method to obtain the
 3380: starting resource.
 3381: 
 3382: Resource objects respect the parameter_hiddenparts, which suppresses 
 3383: various parts according to the wishes of the map author. As of this
 3384: writing, there is no way to override this parameter, and suppressed
 3385: parts will never be returned, nor will their response types or ids be
 3386: stored.
 3387: 
 3388: =head2 Overview
 3389: 
 3390: A B<Resource> is the most granular type of object in LON-CAPA that can
 3391: be included in a course. It can either be a particular resource, like
 3392: an HTML page, external resource, problem, etc., or it can be a
 3393: container sequence, such as a "page" or a "map".
 3394: 
 3395: To see a sequence from the user's point of view, please see the
 3396: B<Creating a Course: Maps and Sequences> chapter of the Author's
 3397: Manual.
 3398: 
 3399: A Resource Object, once obtained from a navmap object via a B<getBy*>
 3400: method of the navmap, or from an iterator, allows you to query
 3401: information about that resource.
 3402: 
 3403: Generally, you do not ever want to create a resource object yourself,
 3404: so creation has been left undocumented. Always retrieve resources
 3405: from navmap objects.
 3406: 
 3407: =head3 Identifying Resources
 3408: 
 3409: X<big hash>Every resource is identified by a Resource ID in the big hash that is
 3410: unique to that resource for a given course. X<resource ID, in big hash>
 3411: The Resource ID has the form #.#, where the first number is the same
 3412: for every resource in a map, and the second is unique. For instance,
 3413: for a course laid out like this:
 3414: 
 3415:  * Problem 1
 3416:  * Map
 3417:    * Resource 2
 3418:    * Resource 3
 3419: 
 3420: C<Problem 1> and C<Map> will share a first number, and C<Resource 2>
 3421: C<Resource 3> will share a first number. The second number may end up
 3422: re-used between the two groups.
 3423: 
 3424: The resource ID is only used in the big hash, but can be used in the
 3425: context of a course to identify a resource easily. (For instance, the
 3426: printing system uses it to record which resources from a sequence you 
 3427: wish to print.)
 3428: 
 3429: X<symb> X<resource, symb>
 3430: All resources also have B<symb>s, which uniquely identify a resource
 3431: in a course. Many internal LON-CAPA functions expect a symb. A symb
 3432: carries along with it the URL of the resource, and the map it appears
 3433: in. Symbs are much larger than resource IDs.
 3434: 
 3435: =cut
 3436: 
 3437: sub new {
 3438:     # magic invocation to create a class instance
 3439:     my $proto = shift;
 3440:     my $class = ref($proto) || $proto;
 3441:     my $self = {};
 3442: 
 3443:     weaken($self->{NAV_MAP} = shift);
 3444:     $self->{ID} = shift;
 3445: 
 3446:     # Store this new resource in the parent nav map's cache.
 3447:     $self->{NAV_MAP}->{RESOURCE_CACHE}->{$self->{ID}} = $self;
 3448:     $self->{RESOURCE_ERROR} = 0;
 3449: 
 3450:     # A hash that can be used by two-pass algorithms to store data
 3451:     # about this resource in. Not used by the resource object
 3452:     # directly.
 3453:     $self->{DATA} = {};
 3454:    
 3455:     bless($self);
 3456:     
 3457:     return $self;
 3458: }
 3459: 
 3460: # private function: simplify the NAV_HASH lookups we keep doing
 3461: # pass the name, and to automatically append my ID, pass a true val on the
 3462: # second param
 3463: sub navHash {
 3464:     my $self = shift;
 3465:     my $param = shift;
 3466:     my $id = shift;
 3467:     my $arg = $param . ($id?$self->{ID}:"");
 3468:     if (ref($self) && ref($self->{NAV_MAP}) && defined($arg)) {
 3469:         return $self->{NAV_MAP}->navhash($arg);
 3470:     }
 3471:     return;
 3472: }
 3473: 
 3474: =pod
 3475: 
 3476: =head2 Methods
 3477: 
 3478: Once you have a resource object, here's what you can do with it:
 3479: 
 3480: =head3 Attribute Retrieval
 3481: 
 3482: Every resource has certain attributes that can be retrieved and used:
 3483: 
 3484: =over 4
 3485: 
 3486: =item * B<ID>: Every resource has an ID that is unique for that
 3487:     resource in the course it is in. The ID is actually in the hash
 3488:     representing the resource, so for a resource object $res, obtain
 3489:     it via C<$res->{ID}).
 3490: 
 3491: =item * B<compTitle>:
 3492: 
 3493: Returns a "composite title", that is equal to $res->title() if the
 3494: resource has a title, and is otherwise the last part of the URL (e.g.,
 3495: "problem.problem").
 3496: 
 3497: =item * B<ext>:
 3498: 
 3499: Returns true if the resource is external.
 3500: 
 3501: =item * B<kind>:
 3502: 
 3503: Returns the kind of the resource from the compiled nav map.
 3504: 
 3505: =item * B<randomout>:
 3506: 
 3507: Returns true if this resource was chosen to NOT be shown to the user
 3508: by the random map selection feature. In other words, this is usually
 3509: false.
 3510: 
 3511: =item * B<randompick>:
 3512: 
 3513: Returns the number of randomly picked items for a map if the randompick
 3514: feature is being used on the map. 
 3515: 
 3516: =item * B<randomorder>:
 3517: 
 3518: Returns true for a map if the randomorder feature is being used on the
 3519: map.
 3520: 
 3521: =item * B<src>:
 3522: 
 3523: Returns the source for the resource.
 3524: 
 3525: =item * B<symb>:
 3526: 
 3527: Returns the symb for the resource.
 3528: 
 3529: =item * B<title>:
 3530: 
 3531: Returns the title of the resource.
 3532: 
 3533: =back
 3534: 
 3535: =cut
 3536: 
 3537: # These info functions can be used directly, as they don't return
 3538: # resource information.
 3539: sub comesfrom { my $self=shift; return $self->navHash("comesfrom_", 1); }
 3540: sub encrypted { my $self=shift; return $self->navHash("encrypted_", 1); }
 3541: sub ext { my $self=shift; return $self->navHash("ext_", 1) eq 'true:'; }
 3542: sub from { my $self=shift; return $self->navHash("from_", 1); }
 3543: # considered private and undocumented
 3544: sub goesto { my $self=shift; return $self->navHash("goesto_", 1); }
 3545: sub kind { my $self=shift; return $self->navHash("kind_", 1); }
 3546: sub randomout { my $self=shift; return $self->navHash("randomout_", 1); }
 3547: sub randompick { 
 3548:     my $self = shift;
 3549:     my $randompick = $self->parmval('randompick');
 3550:     return $randompick;
 3551: }
 3552: sub randomorder { 
 3553:     my $self = shift;
 3554:     my $randomorder = $self->parmval('randomorder');
 3555:     return ($randomorder =~ /^yes$/i);
 3556: }
 3557: sub link {
 3558:     my $self=shift;
 3559:     if ($self->encrypted()) { return &Apache::lonenc::encrypted($self->src); }
 3560:     return $self->src;
 3561: }
 3562: sub src { 
 3563:     my $self=shift;
 3564:     return $self->navHash("src_", 1);
 3565: }
 3566: sub shown_symb {
 3567:     my $self=shift;
 3568:     if ($self->encrypted()) {return &Apache::lonenc::encrypted($self->symb());}
 3569:     return $self->symb();
 3570: }
 3571: sub id {
 3572:     my $self=shift;
 3573:     return $self->{ID};
 3574: }
 3575: sub enclosing_map_src {
 3576:     my $self=shift;
 3577:     (my $first, my $second) = $self->{ID} =~ /(\d+).(\d+)/;
 3578:     return $self->navHash('map_id_'.$first);
 3579: }
 3580: sub symb {
 3581:     my $self=shift;
 3582:     (my $first, my $second) = $self->{ID} =~ /(\d+).(\d+)/;
 3583:     my $symbSrc = &Apache::lonnet::declutter($self->src());
 3584:     my $symb = &Apache::lonnet::declutter($self->navHash('map_id_'.$first)) 
 3585:         . '___' . $second . '___' . $symbSrc;
 3586:     return &Apache::lonnet::symbclean($symb);
 3587: }
 3588: sub wrap_symb {
 3589:     my $self = shift;
 3590:     return $self->{NAV_MAP}->wrap_symb($self->symb());
 3591: }
 3592: sub title { 
 3593:     my $self=shift; 
 3594:     if ($self->{ID} eq '0.0') {
 3595: 	# If this is the top-level map, return the title of the course
 3596: 	# since this map can not be titled otherwise.
 3597: 	return $env{'course.'.$env{'request.course.id'}.'.description'};
 3598:     }
 3599:     return $self->navHash("title_", 1); }
 3600: # considered private and undocumented
 3601: sub to { my $self=shift; return $self->navHash("to_", 1); }
 3602: sub condition {
 3603:     my $self=shift;
 3604:     my $undercond=$self->navHash("undercond_", 1);
 3605:     if (!defined($undercond)) { return 1; };
 3606:     my $condid=$self->navHash("condid_$undercond");
 3607:     if (!defined($condid)) { return 1; };
 3608:     my $condition=&Apache::lonnet::directcondval($condid);
 3609:     return $condition;
 3610: }
 3611: sub condval {
 3612:     my $self=shift;
 3613:     my ($pathname,$filename) = 
 3614: 	&Apache::lonnet::split_uri_for_cond($self->src());
 3615: 
 3616:     my $match=($env{'acc.res.'.$env{'request.course.id'}.'.'.$pathname}=~
 3617: 	       /\&\Q$filename\E\:([\d\|]+)\&/);
 3618:     if ($match) {
 3619: 	return &Apache::lonnet::condval($1);
 3620:     }
 3621:     return 0;
 3622: }
 3623: sub compTitle {
 3624:     my $self = shift;
 3625:     my $title = $self->title();
 3626:     $title=~s/\&colon\;/\:/gs;
 3627:     if (!$title) {
 3628:         $title = $self->src();
 3629:         $title = substr($title, rindex($title, '/') + 1);
 3630:     }
 3631:     return $title;
 3632: }
 3633: 
 3634: =pod
 3635: 
 3636: B<Predicate Testing the Resource>
 3637: 
 3638: These methods are shortcuts to deciding if a given resource has a given property.
 3639: 
 3640: =over 4
 3641: 
 3642: =item * B<is_map>:
 3643: 
 3644: Returns true if the resource is a map type.
 3645: 
 3646: =item * B<is_problem>:
 3647: 
 3648: Returns true if the resource is a problem type, false
 3649: otherwise. (Looks at the extension on the src field; might need more
 3650: to work correctly.)
 3651: 
 3652: =item * B<is_page>:
 3653: 
 3654: Returns true if the resource is a page.
 3655: 
 3656: =item * B<is_sequence>:
 3657: 
 3658: Returns true if the resource is a sequence.
 3659: 
 3660: =back
 3661: 
 3662: =cut
 3663: 
 3664: sub hasResource {
 3665:    my $self = shift;
 3666:    return $self->{NAV_MAP}->hasResource(@_);
 3667: }
 3668: 
 3669: sub retrieveResources {
 3670:    my $self = shift;
 3671:    return $self->{NAV_MAP}->retrieveResources(@_);
 3672: }
 3673: 
 3674: sub is_exam {
 3675:     my ($self,$part) = @_;
 3676:     my $type = $self->parmval('type',$part);
 3677:     if ($type eq 'exam') {
 3678:         return 1;
 3679:     }
 3680:     if ($self->src() =~ /\.(exam)$/) {
 3681:         return 1;
 3682:     }
 3683:     return 0;
 3684: }
 3685: sub is_html {
 3686:     my $self=shift;
 3687:     my $src = $self->src();
 3688:     return ($src =~ /html$/);
 3689: }
 3690: sub is_map { my $self=shift; return defined($self->navHash("is_map_", 1)); }
 3691: sub is_page {
 3692:     my $self=shift;
 3693:     my $src = $self->src();
 3694:     return $self->navHash("is_map_", 1) && 
 3695: 	$self->navHash("map_type_" . $self->map_pc()) eq 'page';
 3696: }
 3697: sub is_practice {
 3698:     my $self=shift;
 3699:     my ($part) = @_;
 3700:     my $type = $self->parmval('type',$part);
 3701:     if ($type eq 'practice') {
 3702:         return 1;
 3703:     }
 3704:     return 0;
 3705: }
 3706: sub is_problem {
 3707:     my $self=shift;
 3708:     my $src = $self->src();
 3709:     if ($src =~ /\.(problem|exam|quiz|assess|survey|form|library|task)$/) {
 3710: 	return !($self->is_practice());
 3711:     }
 3712:     return 0;
 3713: }
 3714: #
 3715: #  The has below is the set of status that are considered 'incomplete'
 3716: #
 3717: my %incomplete_hash = 
 3718: (
 3719:  TRIES_LEFT()     => 1,
 3720:  OPEN()           => 1,
 3721:  ATTEMPTED()      => 1
 3722: 
 3723:  );
 3724: #
 3725: #  Return tru if a problem is incomplete... for now incomplete means that
 3726: #  any part of the problem is incomplete. 
 3727: #  Note that if the resources is not a problem, 0 is returned.
 3728: #
 3729: sub is_incomplete {
 3730:     my $self = shift;
 3731:     if ($self->is_problem()) {
 3732: 	&Apache::lonnet::logthis('is problem');
 3733: 	foreach my $part (@{$self->parts()}) {
 3734: 	    &Apache::lonnet::logthis("$part status ".$self->status($part));
 3735: 	    if (exists($incomplete_hash{$self->status($part)})) {
 3736: 		return 1;
 3737: 	    }
 3738: 	}
 3739:     }
 3740:     return 0;
 3741:        
 3742: }
 3743: sub is_raw_problem {
 3744:     my $self=shift;
 3745:     my $src = $self->src();
 3746:     if ($src =~ /\.(problem|exam|quiz|assess|survey|form|library|task)$/) {
 3747:         return 1;
 3748:     }
 3749:     return 0;
 3750: }
 3751: 
 3752: sub contains_problem {
 3753:     my $self=shift;
 3754:     if ($self->is_page()) {
 3755: 	my $hasProblem=$self->hasResource($self,sub { $_[0]->is_problem() },1);
 3756: 	return $hasProblem;
 3757:     }
 3758:     return 0;
 3759: }
 3760: sub map_contains_problem {
 3761:     my $self=shift;
 3762:     if ($self->is_map()) {
 3763: 	my $has_problem=
 3764: 	    $self->hasResource($self,sub { $_[0]->is_problem() },1);
 3765: 	return $has_problem;
 3766:     }
 3767:     return 0;
 3768: }
 3769: sub is_sequence {
 3770:     my $self=shift;
 3771:     return $self->navHash("is_map_", 1) && 
 3772:     $self->navHash("map_type_" . $self->map_pc()) eq 'sequence';
 3773: }
 3774: sub is_survey {
 3775:     my $self = shift();
 3776:     my $part = shift();
 3777:     my $type = $self->parmval('type',$part);
 3778:     if (($type eq 'survey') || ($type eq 'surveycred')) {
 3779:         return 1;
 3780:     }
 3781:     if ($self->src() =~ /\.(survey)$/) {
 3782:         return 1;
 3783:     }
 3784:     return 0;
 3785: }
 3786: sub is_anonsurvey {
 3787:     my $self = shift();
 3788:     my $part = shift();
 3789:     my $type = $self->parmval('type',$part);
 3790:     if (($type eq 'anonsurvey') || ($type eq 'anonsurveycred')) {
 3791:         return 1;
 3792:     }
 3793:     return 0;
 3794: }
 3795: sub is_task {
 3796:     my $self=shift;
 3797:     my $src = $self->src();
 3798:     return ($src =~ /\.(task)$/)
 3799: }
 3800: 
 3801: sub is_empty_sequence {
 3802:     my $self=shift;
 3803:     my $src = $self->src();
 3804:     return !$self->is_page() && $self->navHash("is_map_", 1) && !$self->navHash("map_type_" . $self->map_pc());
 3805: }
 3806: 
 3807: # Private method: Shells out to the parmval in the nav map, handler parts.
 3808: sub parmval {
 3809:     my $self = shift;
 3810:     my $what = shift;
 3811:     my $part = shift;
 3812:     if (!defined($part)) { 
 3813:         $part = '0'; 
 3814:     }
 3815:     return $self->{NAV_MAP}->parmval($part.'.'.$what, $self->symb());
 3816: }
 3817: 
 3818: =pod
 3819: 
 3820: B<Map Methods>
 3821: 
 3822: These methods are useful for getting information about the map
 3823: properties of the resource, if the resource is a map (B<is_map>).
 3824: 
 3825: =over 4
 3826: 
 3827: =item * B<map_finish>:
 3828: 
 3829: Returns a reference to a resource object corresponding to the finish
 3830: resource of the map.
 3831: 
 3832: =item * B<map_pc>:
 3833: 
 3834: Returns the pc value of the map, which is the first number that
 3835: appears in the resource ID of the resources in the map, and is the
 3836: number that appears around the middle of the symbs of the resources in
 3837: that map.
 3838: 
 3839: =item * B<map_start>:
 3840: 
 3841: Returns a reference to a resource object corresponding to the start
 3842: resource of the map.
 3843: 
 3844: =item * B<map_type>:
 3845: 
 3846: Returns a string with the type of the map in it.
 3847: 
 3848: =item *B<map_hierarchy>:
 3849: 
 3850: Returns a string with a comma-separated ordered list of map_pc IDs
 3851: for the hierarchy of maps containing a map, with the top level
 3852: map first, then descending to deeper levels, with the enclosing map last.
 3853: 
 3854: =back
 3855: 
 3856: =cut
 3857: 
 3858: sub map_finish {
 3859:     my $self = shift;
 3860:     my $src = $self->src();
 3861:     $src = &Apache::lonnet::clutter($src);
 3862:     my $res = $self->navHash("map_finish_$src", 0);
 3863:     $res = $self->{NAV_MAP}->getById($res);
 3864:     return $res;
 3865: }
 3866: sub map_pc {
 3867:     my $self = shift;
 3868:     my $src = $self->src();
 3869:     return $self->navHash("map_pc_$src", 0);
 3870: }
 3871: sub map_start {
 3872:     my $self = shift;
 3873:     my $src = $self->src();
 3874:     $src = &Apache::lonnet::clutter($src);
 3875:     my $res = $self->navHash("map_start_$src", 0);
 3876:     $res = $self->{NAV_MAP}->getById($res);
 3877:     return $res;
 3878: }
 3879: sub map_type {
 3880:     my $self = shift;
 3881:     my $pc = $self->map_pc();
 3882:     return $self->navHash("map_type_$pc", 0);
 3883: }
 3884: sub map_hierarchy {
 3885:     my $self = shift;
 3886:     my $pc = $self->map_pc();
 3887:     return $self->navHash("map_hierarchy_$pc", 0);
 3888: }
 3889: 
 3890: #####
 3891: # Property queries
 3892: #####
 3893: 
 3894: # These functions will be responsible for returning the CORRECT
 3895: # VALUE for the parameter, no matter what. So while they may look
 3896: # like direct calls to parmval, they can be more than that.
 3897: # So, for instance, the duedate function should use the "duedatetype"
 3898: # information, rather than the resource object user.
 3899: 
 3900: =pod
 3901: 
 3902: =head2 Resource Parameters
 3903: 
 3904: In order to use the resource parameters correctly, the nav map must
 3905: have been instantiated with genCourseAndUserOptions set to true, so
 3906: the courseopt and useropt is read correctly. Then, you can call these
 3907: functions to get the relevant parameters for the resource. Each
 3908: function defaults to part "0", but can be directed to another part by
 3909: passing the part as the parameter.
 3910: 
 3911: These methods are responsible for getting the parameter correct, not
 3912: merely reflecting the contents of the GDBM hashes. As we move towards
 3913: dates relative to other dates, these methods should be updated to
 3914: reflect that. (Then, anybody using these methods will not have to update
 3915: their code.)
 3916: 
 3917: =over 4
 3918: 
 3919: =item * B<acc>:
 3920: 
 3921: Get the Client IP/Name Access Control information.
 3922: 
 3923: =item * B<answerdate>:
 3924: 
 3925: Get the answer-reveal date for the problem.
 3926: 
 3927: =item * B<awarded>: 
 3928: 
 3929: Gets the awarded value for the problem part. Requires genUserData set to
 3930: true when the navmap object was created.
 3931: 
 3932: =item * B<duedate>:
 3933: 
 3934: Get the due date for the problem.
 3935: 
 3936: =item * B<tries>:
 3937: 
 3938: Get the number of tries the student has used on the problem.
 3939: 
 3940: =item * B<maxtries>:
 3941: 
 3942: Get the number of max tries allowed.
 3943: 
 3944: =item * B<opendate>:
 3945: 
 3946: Get the open date for the problem.
 3947: 
 3948: =item * B<sig>:
 3949: 
 3950: Get the significant figures setting.
 3951: 
 3952: =item * B<tol>:
 3953: 
 3954: Get the tolerance for the problem.
 3955: 
 3956: =item * B<tries>:
 3957: 
 3958: Get the number of tries the user has already used on the problem.
 3959: 
 3960: =item * B<type>:
 3961: 
 3962: Get the question type for the problem.
 3963: 
 3964: =item * B<weight>:
 3965: 
 3966: Get the weight for the problem.
 3967: 
 3968: =back
 3969: 
 3970: =cut
 3971: 
 3972: sub acc {
 3973:     (my $self, my $part) = @_;
 3974:     my $acc = $self->parmval("acc", $part);
 3975:     return $acc;
 3976: }
 3977: sub answerdate {
 3978:     (my $self, my $part) = @_;
 3979:     # Handle intervals
 3980:     my $answerdatetype = $self->parmval("answerdate.type", $part);
 3981:     my $answerdate = $self->parmval("answerdate", $part);
 3982:     my $duedate = $self->parmval("duedate", $part);
 3983:     if ($answerdatetype eq 'date_interval') {
 3984:         $answerdate = $duedate + $answerdate; 
 3985:     }
 3986:     return $answerdate;
 3987: }
 3988: sub awarded { 
 3989:     my $self = shift; my $part = shift;
 3990:     $self->{NAV_MAP}->get_user_data();
 3991:     if (!defined($part)) { $part = '0'; }
 3992:     return $self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$part.'.awarded'};
 3993: }
 3994: sub taskversion {
 3995:     my $self = shift; my $part = shift;
 3996:     $self->{NAV_MAP}->get_user_data();
 3997:     if (!defined($part)) { $part = '0'; }
 3998:     return $self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$part.'.version'};
 3999: }
 4000: sub taskstatus {
 4001:     my $self = shift; my $part = shift;
 4002:     $self->{NAV_MAP}->get_user_data();
 4003:     if (!defined($part)) { $part = '0'; }
 4004:     return $self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$self->taskversion($part).'.'.$part.'.status'};
 4005: }
 4006: sub solved {
 4007:     my $self = shift; my $part = shift;
 4008:     $self->{NAV_MAP}->get_user_data();
 4009:     if (!defined($part)) { $part = '0'; }
 4010:     return $self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$part.'.solved'};
 4011: }
 4012: sub checkedin {
 4013:     my $self = shift; my $part = shift;
 4014:     $self->{NAV_MAP}->get_user_data();
 4015:     if (!defined($part)) { $part = '0'; }
 4016:     if ($self->is_task()) {
 4017:         my $version = $self->taskversion($part);
 4018:         return ($self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$version .'.'.$part.'.checkedin'},$self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$version .'.'.$part.'.checkedin.slot'});
 4019:     } else {
 4020:         return ($self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$part.'.checkedin'},$self->{NAV_MAP}->{STUDENT_DATA}->{$self->symb()}->{'resource.'.$part.'.checkedin.slot'});
 4021:     }
 4022: }
 4023: # this should work exactly like the copy in lonhomework.pm
 4024: sub duedate {
 4025:     (my $self, my $part) = @_;
 4026:     my $date;
 4027:     my @interval=$self->parmval("interval", $part);
 4028:     my $due_date=$self->parmval("duedate", $part);
 4029:     if ($interval[0] =~ /\d+/) {
 4030:        my $first_access=&Apache::lonnet::get_first_access($interval[1],
 4031:                                                           $self->symb);
 4032: 	if (defined($first_access)) {
 4033:            my $interval = $first_access+$interval[0];
 4034: 	    $date = (!$due_date || $interval < $due_date) ? $interval 
 4035:                                                           : $due_date;
 4036: 	} else {
 4037: 	    $date = $due_date;
 4038: 	}
 4039:     } else {
 4040: 	$date = $due_date;
 4041:     }
 4042:     return $date;
 4043: }
 4044: sub handgrade {
 4045:     (my $self, my $part) = @_;
 4046:     my @response_ids = $self->responseIds($part);
 4047:     if (@response_ids) {
 4048: 	foreach my $response_id (@response_ids) {
 4049:             my $handgrade = $self->parmval("handgrade",$part.'_'.$response_id);
 4050: 	    if (lc($handgrade) eq 'yes') {
 4051: 		return 'yes';
 4052: 	    }
 4053: 	}
 4054:     }
 4055:     my $handgrade = $self->parmval("handgrade", $part);
 4056:     return $handgrade;
 4057: }
 4058: sub maxtries {
 4059:     (my $self, my $part) = @_;
 4060:     my $maxtries = $self->parmval("maxtries", $part);
 4061:     return $maxtries;
 4062: }
 4063: sub opendate {
 4064:     (my $self, my $part) = @_;
 4065:     my $opendatetype = $self->parmval("opendate.type", $part);
 4066:     my $opendate = $self->parmval("opendate", $part); 
 4067:     if ($opendatetype eq 'date_interval') {
 4068:         my $duedate = $self->duedate($part);
 4069:         $opendate = $duedate - $opendate; 
 4070:     }
 4071:     return $opendate;
 4072: }
 4073: sub problemstatus {
 4074:     (my $self, my $part) = @_;
 4075:     my $problemstatus = $self->parmval("problemstatus", $part);
 4076:     return lc($problemstatus);
 4077: }
 4078: sub sig {
 4079:     (my $self, my $part) = @_;
 4080:     my $sig = $self->parmval("sig", $part);
 4081:     return $sig;
 4082: }
 4083: sub tol {
 4084:     (my $self, my $part) = @_;
 4085:     my $tol = $self->parmval("tol", $part);
 4086:     return $tol;
 4087: }
 4088: sub tries {
 4089:     my $self = shift; 
 4090:     my $tries = $self->queryRestoreHash('tries', shift);
 4091:     if (!defined($tries)) { return '0';}
 4092:     return $tries;
 4093: }
 4094: sub type {
 4095:     (my $self, my $part) = @_;
 4096:     my $type = $self->parmval("type", $part);
 4097:     return $type;
 4098: }
 4099: sub weight { 
 4100:     my $self = shift; my $part = shift;
 4101:     if (!defined($part)) { $part = '0'; }
 4102:     my $weight = &Apache::lonnet::EXT('resource.'.$part.'.weight',
 4103:                                 $self->symb(), $env{'user.domain'},
 4104:                                 $env{'user.name'},
 4105:                                 $env{'request.course.sec'});
 4106:     return $weight;
 4107: }
 4108: sub part_display {
 4109:     my $self= shift(); my $partID = shift();
 4110:     if (! defined($partID)) { $partID = '0'; }
 4111:     my $display=&Apache::lonnet::EXT('resource.'.$partID.'.display',
 4112:                                      $self->symb);
 4113:     if (! defined($display) || $display eq '') {
 4114:         $display = $partID;
 4115:     }
 4116:     return $display;
 4117: }
 4118: sub slot_control {
 4119:     my $self=shift(); my $part = shift();
 4120:     if (!defined($part)) { $part = '0'; }
 4121:     my $useslots = $self->parmval("useslots", $part);
 4122:     my $availablestudent = $self->parmval("availablestudent", $part);
 4123:     my $available = $self->parmval("available", $part); 
 4124:     return ($useslots,$availablestudent,$available);
 4125: }
 4126: 
 4127: # Multiple things need this
 4128: sub getReturnHash {
 4129:     my $self = shift;
 4130:     
 4131:     if (!defined($self->{RETURN_HASH})) {
 4132:         my %tmpHash  = &Apache::lonnet::restore($self->symb());
 4133:         $self->{RETURN_HASH} = \%tmpHash;
 4134:     }
 4135: }       
 4136: 
 4137: ######
 4138: # Status queries
 4139: ######
 4140: 
 4141: # These methods query the status of problems.
 4142: 
 4143: # If we need to count parts, this function determines the number of
 4144: # parts from the metadata. When called, it returns a reference to a list
 4145: # of strings corresponding to the parts. (Thus, using it in a scalar context
 4146: # tells you how many parts you have in the problem:
 4147: # $partcount = scalar($resource->countParts());
 4148: # Don't use $self->{PARTS} directly because you don't know if it's been
 4149: # computed yet.
 4150: 
 4151: =pod
 4152: 
 4153: =head2 Resource misc
 4154: 
 4155: Misc. functions for the resource.
 4156: 
 4157: =over 4
 4158: 
 4159: =item * B<hasDiscussion>:
 4160: 
 4161: Returns a false value if there has been discussion since the user last
 4162: logged in, true if there has. Always returns false if the discussion
 4163: data was not extracted when the nav map was constructed.
 4164: 
 4165: =item * B<last_post_time>:
 4166: 
 4167: Returns a false value if there hasn't been discussion otherwise returns
 4168: unix timestamp of last time a discussion posting (or edit) was made.
 4169: 
 4170: =item * B<discussion_info>:
 4171: 
 4172: optional argument is a filter (currently can be 'unread');
 4173: returns in scalar context the count of the number of discussion postings.
 4174: 
 4175: returns in list context both the count of postings and a hash ref
 4176: containing information about the postings (subject, id, timestamp) in a hash.
 4177: 
 4178: Default is to return counts for all postings.  However if called with a second argument set to 'unread', will return information about only unread postings.
 4179: 
 4180: =item * B<getFeedback>:
 4181: 
 4182: Gets the feedback for the resource and returns the raw feedback string
 4183: for the resource, or the null string if there is no feedback or the
 4184: email data was not extracted when the nav map was constructed. Usually
 4185: used like this:
 4186: 
 4187:  for my $url (split(/\,/, $res->getFeedback())) {
 4188:     my $link = &escape($url);
 4189:     ...
 4190: 
 4191: and use the link as appropriate.
 4192: 
 4193: =cut
 4194: 
 4195: sub hasDiscussion {
 4196:     my $self = shift;
 4197:     return $self->{NAV_MAP}->hasDiscussion($self->symb());
 4198: }
 4199: 
 4200: sub last_post_time {
 4201:     my $self = shift;
 4202:     return $self->{NAV_MAP}->last_post_time($self->symb());
 4203: }
 4204: 
 4205: sub discussion_info {
 4206:     my ($self,$filter) = @_;
 4207:     return $self->{NAV_MAP}->discussion_info($self->symb(),$filter);
 4208: }
 4209: 
 4210: sub getFeedback {
 4211:     my $self = shift;
 4212:     my $source = $self->src();
 4213:     my $symb = $self->symb();
 4214:     if ($source =~ /^\/res\//) { $source = substr $source, 5; }
 4215:     return $self->{NAV_MAP}->getFeedback($symb,$source);
 4216: }
 4217: 
 4218: sub getErrors {
 4219:     my $self = shift;
 4220:     my $source = $self->src();
 4221:     my $symb = $self->symb();
 4222:     if ($source =~ /^\/res\//) { $source = substr $source, 5; }
 4223:     return $self->{NAV_MAP}->getErrors($symb,$source);
 4224: }
 4225: 
 4226: =pod
 4227: 
 4228: =item * B<parts>():
 4229: 
 4230: Returns a list reference containing sorted strings corresponding to
 4231: each part of the problem. Single part problems have only a part '0'.
 4232: Multipart problems do not return their part '0', since they typically
 4233: do not really matter. 
 4234: 
 4235: =item * B<countParts>():
 4236: 
 4237: Returns the number of parts of the problem a student can answer. Thus,
 4238: for single part problems, returns 1. For multipart, it returns the
 4239: number of parts in the problem, not including psuedo-part 0. 
 4240: 
 4241: =item * B<countResponses>():
 4242: 
 4243: Returns the total number of responses in the problem a student can answer.
 4244: 
 4245: =item * B<responseTypes>():
 4246: 
 4247: Returns a hash whose keys are the response types.  The values are the number 
 4248: of times each response type is used.  This is for the I<entire> problem, not 
 4249: just a single part.
 4250: 
 4251: =item * B<multipart>():
 4252: 
 4253: Returns true if the problem is multipart, false otherwise. Use this instead
 4254: of countParts if all you want is multipart/not multipart.
 4255: 
 4256: =item * B<responseType>($part):
 4257: 
 4258: Returns the response type of the part, without the word "response" on the
 4259: end. Example return values: 'string', 'essay', 'numeric', etc.
 4260: 
 4261: =item * B<responseIds>($part):
 4262: 
 4263: Retreives the response IDs for the given part as an array reference containing
 4264: strings naming the response IDs. This may be empty.
 4265: 
 4266: =back
 4267: 
 4268: =cut
 4269: 
 4270: sub parts {
 4271:     my $self = shift;
 4272: 
 4273:     if ($self->ext) { return []; }
 4274: 
 4275:     $self->extractParts();
 4276:     return $self->{PARTS};
 4277: }
 4278: 
 4279: sub countParts {
 4280:     my $self = shift;
 4281:     
 4282:     my $parts = $self->parts();
 4283: 
 4284:     # If I left this here, then it's not necessary.
 4285:     #my $delta = 0;
 4286:     #for my $part (@$parts) {
 4287:     #    if ($part eq '0') { $delta--; }
 4288:     #}
 4289: 
 4290:     if ($self->{RESOURCE_ERROR}) {
 4291:         return 0;
 4292:     }
 4293: 
 4294:     return scalar(@{$parts}); # + $delta;
 4295: }
 4296: 
 4297: sub countResponses {
 4298:     my $self = shift;
 4299:     my $count;
 4300:     foreach my $part (@{$self->parts()}) {
 4301:         $count+= scalar($self->responseIds($part));
 4302:     }
 4303:     return $count;
 4304: }
 4305: 
 4306: sub responseTypes {
 4307:     my $self = shift;
 4308:     my %responses;
 4309:     foreach my $part (@{$self->parts()}) {
 4310:         foreach my $responsetype ($self->responseType($part)) {
 4311:             $responses{$responsetype}++ if (defined($responsetype));
 4312:         }
 4313:     }
 4314:     return %responses;
 4315: }
 4316: 
 4317: sub multipart {
 4318:     my $self = shift;
 4319:     return $self->countParts() > 1;
 4320: }
 4321: 
 4322: sub singlepart {
 4323:     my $self = shift;
 4324:     return $self->countParts() == 1;
 4325: }
 4326: 
 4327: sub responseType {
 4328:     my $self = shift;
 4329:     my $part = shift;
 4330: 
 4331:     $self->extractParts();
 4332:     if (defined($self->{RESPONSE_TYPES}->{$part})) {
 4333: 	return @{$self->{RESPONSE_TYPES}->{$part}};
 4334:     } else {
 4335: 	return undef;
 4336:     }
 4337: }
 4338: 
 4339: sub responseIds {
 4340:     my $self = shift;
 4341:     my $part = shift;
 4342: 
 4343:     $self->extractParts();
 4344:     if (defined($self->{RESPONSE_IDS}->{$part})) {
 4345: 	return @{$self->{RESPONSE_IDS}->{$part}};
 4346:     } else {
 4347: 	return undef;
 4348:     }
 4349: }
 4350: 
 4351: # Private function: Extracts the parts information, both part names and
 4352: # part types, and saves it. 
 4353: sub extractParts { 
 4354:     my $self = shift;
 4355:     
 4356:     return if (defined($self->{PARTS}));
 4357:     return if ($self->ext);
 4358: 
 4359:     $self->{PARTS} = [];
 4360: 
 4361:     my %parts;
 4362: 
 4363:     # Retrieve part count, if this is a problem
 4364:     if ($self->is_problem()) {
 4365: 	my $partorder = &Apache::lonnet::metadata($self->src(), 'partorder');
 4366:         my $metadata = &Apache::lonnet::metadata($self->src(), 'packages');
 4367: 
 4368: 	if ($partorder) {
 4369: 	    my @parts;
 4370: 	    for my $part (split (/,/,$partorder)) {
 4371: 		if (!Apache::loncommon::check_if_partid_hidden($part, $self->symb())) {
 4372: 		    push @parts, $part;
 4373: 		    $parts{$part} = 1;
 4374: 		}
 4375: 	    }
 4376: 	    $self->{PARTS} = \@parts;
 4377: 	} else {
 4378: 	    if (!$metadata) {
 4379: 		$self->{RESOURCE_ERROR} = 1;
 4380: 		$self->{PARTS} = [];
 4381: 		$self->{PART_TYPE} = {};
 4382: 		return;
 4383: 	    }
 4384: 	    foreach my $entry (split(/\,/,$metadata)) {
 4385: 		if ($entry =~ /^(?:part|Task)_(.*)$/) {
 4386: 		    my $part = $1;
 4387: 		    # This floods the logs if it blows up
 4388: 		    if (defined($parts{$part})) {
 4389: 			&Apache::lonnet::logthis("$part multiply defined in metadata for " . $self->symb());
 4390: 		    }
 4391: 		    
 4392: 		    # check to see if part is turned off.
 4393: 		    
 4394: 		    if (!Apache::loncommon::check_if_partid_hidden($part, $self->symb())) {
 4395: 			$parts{$part} = 1;
 4396: 		    }
 4397: 		}
 4398: 	    }
 4399: 	    my @sortedParts = sort keys %parts;
 4400: 	    $self->{PARTS} = \@sortedParts;
 4401:         }
 4402:         
 4403: 
 4404:         # These hashes probably do not need names that end with "Hash"....
 4405:         my %responseIdHash;
 4406:         my %responseTypeHash;
 4407: 
 4408: 
 4409:         # Init the responseIdHash
 4410:         foreach my $part (@{$self->{PARTS}}) {
 4411:             $responseIdHash{$part} = [];
 4412:         }
 4413: 
 4414:         # Now, the unfortunate thing about this is that parts, part name, and
 4415:         # response id are delimited by underscores, but both the part
 4416:         # name and response id can themselves have underscores in them.
 4417:         # So we have to use our knowlege of part names to figure out 
 4418:         # where the part names begin and end, and even then, it is possible
 4419:         # to construct ambiguous situations.
 4420:         foreach my $data (split /,/, $metadata) {
 4421:             if ($data =~ /^([a-zA-Z]+)response_(.*)/
 4422: 		|| $data =~ /^(Task)_(.*)/) {
 4423:                 my $responseType = $1;
 4424:                 my $partStuff = $2;
 4425:                 my $partIdSoFar = '';
 4426:                 my @partChunks = split /_/, $partStuff;
 4427:                 my $i = 0;
 4428:                 for ($i = 0; $i < scalar(@partChunks); $i++) {
 4429:                     if ($partIdSoFar) { $partIdSoFar .= '_'; }
 4430:                     $partIdSoFar .= $partChunks[$i];
 4431:                     if ($parts{$partIdSoFar}) {
 4432:                         my @otherChunks = @partChunks[$i+1..$#partChunks];
 4433:                         my $responseId = join('_', @otherChunks);
 4434: 			if ($self->is_task()) {
 4435: 			    push(@{$responseIdHash{$partIdSoFar}},
 4436: 				 $partIdSoFar);
 4437: 			} else {
 4438: 			    push(@{$responseIdHash{$partIdSoFar}},
 4439: 				 $responseId);
 4440: 			}
 4441:                         push(@{$responseTypeHash{$partIdSoFar}},
 4442: 			     $responseType);
 4443:                     }
 4444:                 }
 4445:             }
 4446:         }
 4447: 	my $resorder = &Apache::lonnet::metadata($self->src(),'responseorder');
 4448:         #
 4449:         # Reorder the arrays in the %responseIdHash and %responseTypeHash
 4450: 	if ($resorder) {
 4451: 	    my @resorder=split(/,/,$resorder);
 4452: 	    foreach my $part (keys(%responseIdHash)) {
 4453: 		my $i=0;
 4454: 		my %resids = map { ($_,$i++) } @{ $responseIdHash{$part} };
 4455: 		my @neworder;
 4456: 		foreach my $possibleid (@resorder) {
 4457: 		    if (exists($resids{$possibleid})) {
 4458: 			push(@neworder,$resids{$possibleid});
 4459: 		    }
 4460: 		}
 4461: 		my @ids;
 4462: 		my @type;
 4463: 		foreach my $element (@neworder) {
 4464: 		    push (@ids,$responseIdHash{$part}->[$element]);
 4465: 		    push (@type,$responseTypeHash{$part}->[$element]);
 4466: 		}
 4467: 		$responseIdHash{$part}=\@ids;
 4468: 		$responseTypeHash{$part}=\@type;
 4469: 	    }
 4470: 	}
 4471:         $self->{RESPONSE_IDS} = \%responseIdHash;
 4472:         $self->{RESPONSE_TYPES} = \%responseTypeHash;
 4473:     }
 4474: 
 4475:     return;
 4476: }
 4477: 
 4478: =pod
 4479: 
 4480: =head2 Resource Status
 4481: 
 4482: Problem resources have status information, reflecting their various
 4483: dates and completion statuses.
 4484: 
 4485: There are two aspects to the status: the date-related information and
 4486: the completion information.
 4487: 
 4488: Idiomatic usage of these two methods would probably look something
 4489: like
 4490: 
 4491:  foreach my $part ($resource->parts()) {
 4492:     my $dateStatus = $resource->getDateStatus($part);
 4493:     my $completionStatus = $resource->getCompletionStatus($part);
 4494: 
 4495:     or
 4496: 
 4497:     my $status = $resource->status($part);
 4498: 
 4499:     ... use it here ...
 4500:  }
 4501: 
 4502: Which you use depends on exactly what you are looking for. The
 4503: status() function has been optimized for the nav maps display and may
 4504: not precisely match what you need elsewhere.
 4505: 
 4506: The symbolic constants shown below can be accessed through the
 4507: resource object: C<$res->OPEN>.
 4508: 
 4509: =over 4
 4510: 
 4511: =item * B<getDateStatus>($part):
 4512: 
 4513: ($part defaults to 0). A convenience function that returns a symbolic
 4514: constant telling you about the date status of the part. The possible
 4515: return values are:
 4516: 
 4517: =back
 4518: 
 4519: B<Date Codes>
 4520: 
 4521: =over 4
 4522: 
 4523: =item * B<OPEN_LATER>:
 4524: 
 4525: The problem will be opened later.
 4526: 
 4527: =item * B<OPEN>:
 4528: 
 4529: Open and not yet due.
 4530: 
 4531: 
 4532: =item * B<PAST_DUE_ANSWER_LATER>:
 4533: 
 4534: The due date has passed, but the answer date has not yet arrived.
 4535: 
 4536: =item * B<PAST_DUE_NO_ANSWER>:
 4537: 
 4538: The due date has passed and there is no answer opening date set.
 4539: 
 4540: =item * B<ANSWER_OPEN>:
 4541: 
 4542: The answer date is here.
 4543: 
 4544: =item * B<NETWORK_FAILURE>:
 4545: 
 4546: The information is unknown due to network failure.
 4547: 
 4548: =back
 4549: 
 4550: =cut
 4551: 
 4552: # Apparently the compiler optimizes these into constants automatically
 4553: sub OPEN_LATER             { return 0; }
 4554: sub OPEN                   { return 1; }
 4555: sub PAST_DUE_NO_ANSWER     { return 2; }
 4556: sub PAST_DUE_ANSWER_LATER  { return 3; }
 4557: sub ANSWER_OPEN            { return 4; }
 4558: sub NOTHING_SET            { return 5; }
 4559: sub NETWORK_FAILURE        { return 100; }
 4560: 
 4561: # getDateStatus gets the date status for a given problem part. 
 4562: # Because answer date, due date, and open date are fully independent
 4563: # (i.e., it is perfectly possible to *only* have an answer date), 
 4564: # we have to completely cover the 3x3 maxtrix of (answer, due, open) x
 4565: # (past, future, none given). This function handles this with a decision
 4566: # tree. Read the comments to follow the decision tree.
 4567: 
 4568: sub getDateStatus {
 4569:     my $self = shift;
 4570:     my $part = shift;
 4571:     $part = "0" if (!defined($part));
 4572: 
 4573:     # Always return network failure if there was one.
 4574:     return $self->NETWORK_FAILURE if ($self->{NAV_MAP}->{NETWORK_FAILURE});
 4575: 
 4576:     my $now = time();
 4577: 
 4578:     my $open = $self->opendate($part);
 4579:     my $due = $self->duedate($part);
 4580:     my $answer = $self->answerdate($part);
 4581: 
 4582:     if (!$open && !$due && !$answer) {
 4583:         # no data on the problem at all
 4584:         # should this be the same as "open later"? think multipart.
 4585:         return $self->NOTHING_SET;
 4586:     }
 4587:     if (!$open || $now < $open) {return $self->OPEN_LATER}
 4588:     if (!$due || $now < $due) {return $self->OPEN}
 4589:     if ($answer && $now < $answer) {return $self->PAST_DUE_ANSWER_LATER}
 4590:     if ($answer) { return $self->ANSWER_OPEN; }
 4591:     return PAST_DUE_NO_ANSWER;
 4592: }
 4593: 
 4594: =pod
 4595: 
 4596: B<>
 4597: 
 4598: =over 4
 4599: 
 4600: =item * B<getCompletionStatus>($part):
 4601: 
 4602: ($part defaults to 0.) A convenience function that returns a symbolic
 4603: constant telling you about the completion status of the part, with the
 4604: following possible results:
 4605: 
 4606: =back
 4607: 
 4608: B<Completion Codes>
 4609: 
 4610: =over 4
 4611: 
 4612: =item * B<NOT_ATTEMPTED>:
 4613: 
 4614: Has not been attempted at all.
 4615: 
 4616: =item * B<INCORRECT>:
 4617: 
 4618: Attempted, but wrong by student.
 4619: 
 4620: =item * B<INCORRECT_BY_OVERRIDE>:
 4621: 
 4622: Attempted, but wrong by instructor override.
 4623: 
 4624: =item * B<CORRECT>:
 4625: 
 4626: Correct or correct by instructor.
 4627: 
 4628: =item * B<CORRECT_BY_OVERRIDE>:
 4629: 
 4630: Correct by instructor override.
 4631: 
 4632: =item * B<EXCUSED>:
 4633: 
 4634: Excused. Not yet implemented.
 4635: 
 4636: =item * B<NETWORK_FAILURE>:
 4637: 
 4638: Information not available due to network failure.
 4639: 
 4640: =item * B<ATTEMPTED>:
 4641: 
 4642: Attempted, and not yet graded.
 4643: 
 4644: =item * B<CREDIT_ATTEMPTED>:
 4645: 
 4646: Attempted, and credit received for attempt (survey and anonymous survey only).
 4647: 
 4648: =back
 4649: 
 4650: =cut
 4651: 
 4652: sub NOT_ATTEMPTED         { return 10; }
 4653: sub INCORRECT             { return 11; }
 4654: sub INCORRECT_BY_OVERRIDE { return 12; }
 4655: sub CORRECT               { return 13; }
 4656: sub CORRECT_BY_OVERRIDE   { return 14; }
 4657: sub EXCUSED               { return 15; }
 4658: sub ATTEMPTED             { return 16; }
 4659: sub CREDIT_ATTEMPTED      { return 17; }
 4660: 
 4661: sub getCompletionStatus {
 4662:     my $self = shift;
 4663:     my $part = shift;
 4664:     return $self->NETWORK_FAILURE if ($self->{NAV_MAP}->{NETWORK_FAILURE});
 4665: 
 4666:     my $status = $self->queryRestoreHash('solved', $part);
 4667: 
 4668:     # Left as separate if statements in case we ever do more with this
 4669:     if ($status eq 'correct_by_student') {return $self->CORRECT;}
 4670:     if ($status eq 'correct_by_scantron') {return $self->CORRECT;}
 4671:     if ($status eq 'correct_by_override') {
 4672: 	return $self->CORRECT_BY_OVERRIDE;
 4673:     }
 4674:     if ($status eq 'incorrect_attempted') {return $self->INCORRECT; }
 4675:     if ($status eq 'incorrect_by_override') {return $self->INCORRECT_BY_OVERRIDE; }
 4676:     if ($status eq 'excused') {return $self->EXCUSED; }
 4677:     if ($status eq 'ungraded_attempted') {return $self->ATTEMPTED; }
 4678:     if ($status eq 'credit_attempted') {
 4679:         if ($self->is_anonsurvey($part) || $self->is_survey($part)) {
 4680:             return $self->CREDIT_ATTEMPTED;
 4681:         } else {
 4682:             return $self->ATTEMPTED;
 4683:         }
 4684:     }
 4685:     return $self->NOT_ATTEMPTED;
 4686: }
 4687: 
 4688: sub queryRestoreHash {
 4689:     my $self = shift;
 4690:     my $hashentry = shift;
 4691:     my $part = shift;
 4692:     $part = "0" if (!defined($part) || $part eq '');
 4693:     return $self->NETWORK_FAILURE if ($self->{NAV_MAP}->{NETWORK_FAILURE});
 4694: 
 4695:     $self->getReturnHash();
 4696: 
 4697:     return $self->{RETURN_HASH}->{'resource.'.$part.'.'.$hashentry};
 4698: }
 4699: 
 4700: =pod
 4701: 
 4702: B<Composite Status>
 4703: 
 4704: Along with directly returning the date or completion status, the
 4705: resource object includes a convenience function B<status>() that will
 4706: combine the two status tidbits into one composite status that can
 4707: represent the status of the resource as a whole. This method represents
 4708: the concept of the thing we want to display to the user on the nav maps
 4709: screen, which is a combination of completion and open status. The precise logic is
 4710: documented in the comments of the status method. The following results
 4711: may be returned, all available as methods on the resource object
 4712: ($res->NETWORK_FAILURE): In addition to the return values that match
 4713: the date or completion status, this function can return "ANSWER_SUBMITTED"
 4714: if that problemstatus parameter value is set to No, suppressing the
 4715: incorrect/correct feedback.
 4716: 
 4717: =over 4
 4718: 
 4719: =item * B<NETWORK_FAILURE>:
 4720: 
 4721: The network has failed and the information is not available.
 4722: 
 4723: =item * B<NOTHING_SET>:
 4724: 
 4725: No dates have been set for this problem (part) at all. (Because only
 4726: certain parts of a multi-part problem may be assigned, this can not be
 4727: collapsed into "open later", as we do not know a given part will EVER
 4728: be opened. For single part, this is the same as "OPEN_LATER".)
 4729: 
 4730: =item * B<CORRECT>:
 4731: 
 4732: For any reason at all, the part is considered correct.
 4733: 
 4734: =item * B<EXCUSED>:
 4735: 
 4736: For any reason at all, the problem is excused.
 4737: 
 4738: =item * B<PAST_DUE_NO_ANSWER>:
 4739: 
 4740: The problem is past due, not considered correct, and no answer date is
 4741: set.
 4742: 
 4743: =item * B<PAST_DUE_ANSWER_LATER>:
 4744: 
 4745: The problem is past due, not considered correct, and an answer date in
 4746: the future is set.
 4747: 
 4748: =item * B<ANSWER_OPEN>:
 4749: 
 4750: The problem is past due, not correct, and the answer is now available.
 4751: 
 4752: =item * B<OPEN_LATER>:
 4753: 
 4754: The problem is not yet open.
 4755: 
 4756: =item * B<TRIES_LEFT>:
 4757: 
 4758: The problem is open, has been tried, is not correct, but there are
 4759: tries left.
 4760: 
 4761: =item * B<INCORRECT>:
 4762: 
 4763: The problem is open, and all tries have been used without getting the
 4764: correct answer.
 4765: 
 4766: =item * B<OPEN>:
 4767: 
 4768: The item is open and not yet tried.
 4769: 
 4770: =item * B<ATTEMPTED>:
 4771: 
 4772: The problem has been attempted.
 4773: 
 4774: =item * B<CREDIT_ATTEMPTED>:
 4775: 
 4776: The problem has been attempted, and credit given for the attempt (survey and anonymous survey only).
 4777: 
 4778: =item * B<ANSWER_SUBMITTED>:
 4779: 
 4780: An answer has been submitted, but the student should not see it.
 4781: 
 4782: =back
 4783: 
 4784: =cut
 4785: 
 4786: sub TRIES_LEFT        { return 20; }
 4787: sub ANSWER_SUBMITTED  { return 21; }
 4788: sub PARTIALLY_CORRECT { return 22; }
 4789: 
 4790: sub RESERVED_LATER    { return 30; }
 4791: sub RESERVED          { return 31; }
 4792: sub RESERVED_LOCATION { return 32; }
 4793: sub RESERVABLE        { return 33; }
 4794: sub RESERVABLE_LATER  { return 34; }
 4795: sub NOTRESERVABLE     { return 35; }
 4796: sub NOT_IN_A_SLOT     { return 36; }
 4797: sub NEEDS_CHECKIN     { return 37; }
 4798: sub WAITING_FOR_GRADE { return 38; }
 4799: sub UNKNOWN           { return 39; }
 4800: 
 4801: sub status {
 4802:     my $self = shift;
 4803:     my $part = shift;
 4804:     if (!defined($part)) { $part = "0"; }
 4805:     my $completionStatus = $self->getCompletionStatus($part);
 4806:     my $dateStatus = $self->getDateStatus($part);
 4807: 
 4808:     # What we have is a two-dimensional matrix with 4 entries on one
 4809:     # dimension and 5 entries on the other, which we want to colorize,
 4810:     # plus network failure and "no date data at all".
 4811: 
 4812:     #if ($self->{RESOURCE_ERROR}) { return NETWORK_FAILURE; }
 4813:     if ($completionStatus == NETWORK_FAILURE) { return NETWORK_FAILURE; }
 4814: 
 4815:     my $suppressFeedback = 0;
 4816:     if (($self->problemstatus($part) eq 'no') ||
 4817:         ($self->problemstatus($part) eq 'no_feedback_ever')) {
 4818:         $suppressFeedback = 1;
 4819:     }
 4820:     # If there's an answer date and we're past it, don't
 4821:     # suppress the feedback; student should know
 4822:     if ($self->duedate($part) && $self->duedate($part) < time() &&
 4823: 	$self->answerdate($part) && $self->answerdate($part) < time()) {
 4824: 	$suppressFeedback = 0;
 4825:     }
 4826: 
 4827:     # There are a few whole rows we can dispose of:
 4828:     if ($completionStatus == CORRECT ||
 4829:         $completionStatus == CORRECT_BY_OVERRIDE ) {
 4830: 	if ( $suppressFeedback ) { return ANSWER_SUBMITTED }
 4831: 	my $awarded=$self->awarded($part);
 4832: 	if ($awarded < 1 && $awarded > 0) {
 4833:             return PARTIALLY_CORRECT;
 4834: 	} elsif ($awarded<1) {
 4835: 	    return INCORRECT;
 4836: 	}
 4837: 	return CORRECT; 
 4838:     }
 4839: 
 4840:     # If it's WRONG... and not open
 4841:     if ( ($completionStatus == INCORRECT || 
 4842: 	  $completionStatus == INCORRECT_BY_OVERRIDE)
 4843: 	 && (!$self->opendate($part) ||  $self->opendate($part) > time()) ) {
 4844: 	return INCORRECT;
 4845:     }
 4846: 
 4847:     if ($completionStatus == ATTEMPTED) {
 4848:         return ATTEMPTED;
 4849:     }
 4850: 
 4851:     if ($completionStatus == CREDIT_ATTEMPTED) {
 4852:         return CREDIT_ATTEMPTED;
 4853:     }
 4854: 
 4855:     # If it's EXCUSED, then return that no matter what
 4856:     if ($completionStatus == EXCUSED) {
 4857:         return EXCUSED; 
 4858:     }
 4859: 
 4860:     if ($dateStatus == NOTHING_SET) {
 4861:         return NOTHING_SET;
 4862:     }
 4863: 
 4864:     # Now we're down to a 4 (incorrect, incorrect_override, not_attempted)
 4865:     # by 4 matrix (date statuses).
 4866: 
 4867:     if ($dateStatus == PAST_DUE_ANSWER_LATER ||
 4868:         $dateStatus == PAST_DUE_NO_ANSWER ) {
 4869:         return $suppressFeedback ? ANSWER_SUBMITTED : $dateStatus; 
 4870:     }
 4871: 
 4872:     if ($dateStatus == ANSWER_OPEN) {
 4873:         return ANSWER_OPEN;
 4874:     }
 4875: 
 4876:     # Now: (incorrect, incorrect_override, not_attempted) x 
 4877:     # (open_later), (open)
 4878:     
 4879:     if ($dateStatus == OPEN_LATER) {
 4880:         return OPEN_LATER;
 4881:     }
 4882: 
 4883:     # If it's WRONG...
 4884:     if ($completionStatus == INCORRECT || $completionStatus == INCORRECT_BY_OVERRIDE) {
 4885:         # and there are TRIES LEFT:
 4886:         if ($self->tries($part) < $self->maxtries($part) || !$self->maxtries($part)) {
 4887:             return $suppressFeedback ? ANSWER_SUBMITTED : TRIES_LEFT;
 4888:         }
 4889:         return $suppressFeedback ? ANSWER_SUBMITTED : INCORRECT; # otherwise, return orange; student can't fix this
 4890:     }
 4891: 
 4892:     # Otherwise, it's untried and open
 4893:     return OPEN; 
 4894: }
 4895: 
 4896: sub check_for_slot {
 4897:     my $self = shift;
 4898:     my $part = shift;
 4899:     my ($use_slots,$available,$availablestudent) = $self->slot_control($part);
 4900:     if (($use_slots ne '') && ($use_slots !~ /^\s*no\s*$/i)) {
 4901:         my @slots = (split(/:/,$availablestudent),split(/:/,$available));
 4902:         my $cid=$env{'request.course.id'};
 4903:         my $cdom=$env{'course.'.$cid.'.domain'};
 4904:         my $cnum=$env{'course.'.$cid.'.num'};
 4905:         my $now = time;
 4906:         if (@slots > 0) {
 4907:             my %slots=&Apache::lonnet::get('slots',[@slots],$cdom,$cnum);
 4908:             if (&Apache::lonnet::error(%slots)) {
 4909:                 return (UNKNOWN);
 4910:             }
 4911:             my @sorted_slots = &Apache::loncommon::sorted_slots(\@slots,\%slots);
 4912:             my ($checkedin,$checkedinslot);
 4913:             foreach my $slot_name (@sorted_slots) {
 4914:                 next if (!defined($slots{$slot_name}) ||
 4915:                          !ref($slots{$slot_name}));
 4916:                 my $end = $slots{$slot_name}->{'endtime'};
 4917:                 my $start = $slots{$slot_name}->{'starttime'};
 4918:                 my $ip = $slots{$slot_name}->{'ip'};
 4919:                 if ($self->simpleStatus() == OPEN) {
 4920:                     my $startreserve = $slots{$slot_name}->{'startreserve'};
 4921:                     my @proctors;
 4922:                     if ($slots{$slot_name}->{'proctor'} ne '') {
 4923:                         @proctors = split(',',$slots{$slot_name}->{'proctor'});
 4924:                     }
 4925:                     if ($end > $now) {
 4926:                         ($checkedin,$checkedinslot) = $self->checkedin();
 4927:                         if ($startreserve < $now) {
 4928:                             if ($start > $now) {
 4929:                                 return (RESERVED_LATER,$start,$slot_name);
 4930:                             } else {
 4931:                                 if ($ip ne '') {
 4932:                                     if (!&Apache::loncommon::check_ip_acc($ip)) {
 4933:                                         return (RESERVED_LOCATION,$ip,$slot_name);
 4934:                                     }
 4935:                                 } 
 4936:                                 if (@proctors > 0) {
 4937:                                     unless ((grep(/^\Q$checkedin\E/,@proctors)) &&
 4938:                                         ($checkedinslot eq $slot_name)) {
 4939:                                         return (NEEDS_CHECKIN,undef,$slot_name); 
 4940:                                     }
 4941:                                 }
 4942:                                 return (RESERVED,$end,$slot_name);
 4943:                             }
 4944:                         } else {
 4945:                             if ($start > $now) {
 4946:                                 return (RESERVABLE,$startreserve,$slot_name);
 4947:                             }
 4948:                         }
 4949:                     }
 4950:                 }
 4951:             }
 4952:             my ($is_correct,$got_grade);
 4953:             if ($self->is_task()) {
 4954:                 my $taskstatus = $self->taskstatus();
 4955:                 $is_correct = (($taskstatus eq 'pass') || 
 4956:                                ($self->solved() =~ /^correct_/));
 4957:                 $got_grade = ($self->solved() =~ /^(?:pass|fail)$/);
 4958:             } else {
 4959:                 $got_grade = 1;
 4960:                 $is_correct = ($self->solved() =~ /^correct_/);   
 4961:             }
 4962:             ($checkedin,$checkedinslot) = $self->checkedin();
 4963:             if ($checkedin) {
 4964:                 if (!$got_grade) {
 4965:                     return (WAITING_FOR_GRADE);
 4966:                 } elsif ($is_correct) {
 4967:                     return (CORRECT); 
 4968:                 }
 4969:             }
 4970:             return(NOT_IN_A_SLOT);
 4971:         } else {
 4972:             if (!$future_slots_checked) {
 4973:                 $future_slots = &get_future_slots($cdom,$cnum,$now);
 4974:                 $future_slots_checked = 1;
 4975:             }
 4976:             if ($future_slots) {
 4977:                 return(NOT_IN_A_SLOT);
 4978:             }
 4979:             return(NOTRESERVABLE);
 4980:         }
 4981:     }
 4982:     return;
 4983: }
 4984: 
 4985: sub get_future_slots {
 4986:     my ($cdom,$cnum,$now) = @_;
 4987:     my %slots=&Apache::lonnet::dump('slots',$cdom,$cnum);
 4988:     my $future_slots = 0;
 4989:     foreach my $slot (keys(%slots)) {
 4990:         if (($slots{$slot}->{'starttime'} > $now) &&
 4991:             ($slots{$slot}->{'endtime'} > $now)) {
 4992:             $future_slots ++;
 4993:         }
 4994:     }
 4995:     return $future_slots;
 4996: }
 4997: 
 4998: sub CLOSED { return 23; }
 4999: sub ERROR { return 24; }
 5000: 
 5001: =pod
 5002: 
 5003: B<Simple Status>
 5004: 
 5005: Convenience method B<simpleStatus> provides a "simple status" for the resource.
 5006: "Simple status" corresponds to "which icon is shown on the
 5007: Navmaps". There are six "simple" statuses:
 5008: 
 5009: =over 4
 5010: 
 5011: =item * B<CLOSED>: The problem is currently closed. (No icon shown.)
 5012: 
 5013: =item * B<OPEN>: The problem is open and unattempted.
 5014: 
 5015: =item * B<CORRECT>: The problem is correct for any reason.
 5016: 
 5017: =item * B<INCORRECT>: The problem is incorrect and can still be
 5018: completed successfully.
 5019: 
 5020: =item * B<ATTEMPTED>: The problem has been attempted, but the student
 5021: does not know if they are correct. (The ellipsis icon.)
 5022: 
 5023: =item * B<ERROR>: There is an error retrieving information about this
 5024: problem.
 5025: 
 5026: =back
 5027: 
 5028: =cut
 5029: 
 5030: # This hash maps the composite status to this simple status, and
 5031: # can be used directly, if you like
 5032: my %compositeToSimple = 
 5033:     (
 5034:       NETWORK_FAILURE()       => ERROR,
 5035:       NOTHING_SET()           => CLOSED,
 5036:       CORRECT()               => CORRECT,
 5037:       PARTIALLY_CORRECT()     => PARTIALLY_CORRECT,
 5038:       EXCUSED()               => CORRECT,
 5039:       PAST_DUE_NO_ANSWER()    => INCORRECT,
 5040:       PAST_DUE_ANSWER_LATER() => INCORRECT,
 5041:       ANSWER_OPEN()           => INCORRECT,
 5042:       OPEN_LATER()            => CLOSED,
 5043:       TRIES_LEFT()            => OPEN,
 5044:       INCORRECT()             => INCORRECT,
 5045:       OPEN()                  => OPEN,
 5046:       ATTEMPTED()             => ATTEMPTED,
 5047:       CREDIT_ATTEMPTED()      => CORRECT,
 5048:       ANSWER_SUBMITTED()      => ATTEMPTED
 5049:      );
 5050: 
 5051: sub simpleStatus {
 5052:     my $self = shift;
 5053:     my $part = shift;
 5054:     my $status = $self->status($part);
 5055:     return $compositeToSimple{$status};
 5056: }
 5057: 
 5058: =pod
 5059: 
 5060: B<simpleStatusCount> will return an array reference containing, in
 5061: this order, the number of OPEN, CLOSED, CORRECT, INCORRECT, ATTEMPTED,
 5062: and ERROR parts the given problem has.
 5063: 
 5064: =cut
 5065:     
 5066: # This maps the status to the slot we want to increment
 5067: my %statusToSlotMap = 
 5068:     (
 5069:      OPEN()      => 0,
 5070:      CLOSED()    => 1,
 5071:      CORRECT()   => 2,
 5072:      INCORRECT() => 3,
 5073:      ATTEMPTED() => 4,
 5074:      ERROR()     => 5
 5075:      );
 5076: 
 5077: sub statusToSlot { return $statusToSlotMap{shift()}; }
 5078: 
 5079: sub simpleStatusCount {
 5080:     my $self = shift;
 5081: 
 5082:     my @counts = (0, 0, 0, 0, 0, 0, 0);
 5083:     foreach my $part (@{$self->parts()}) {
 5084: 	$counts[$statusToSlotMap{$self->simpleStatus($part)}]++;
 5085:     }
 5086: 
 5087:     return \@counts;
 5088: }
 5089: 
 5090: =pod
 5091: 
 5092: B<Completable>
 5093: 
 5094: The completable method represents the concept of I<whether the student can
 5095: currently do the problem>. If the student can do the problem, which means
 5096: that it is open, there are tries left, and if the problem is manually graded
 5097: or the grade is suppressed via problemstatus, the student has not tried it
 5098: yet, then the method returns 1. Otherwise, it returns 0, to indicate that 
 5099: either the student has tried it and there is no feedback, or that for
 5100: some reason it is no longer completable (not open yet, successfully completed,
 5101: out of tries, etc.). As an example, this is used as the filter for the
 5102: "Uncompleted Homework" option for the nav maps.
 5103: 
 5104: If this does not quite meet your needs, do not fiddle with it (unless you are
 5105: fixing it to better match the student's conception of "completable" because
 5106: it's broken somehow)... make a new method.
 5107: 
 5108: =cut
 5109: 
 5110: sub completable {
 5111:     my $self = shift;
 5112:     if (!$self->is_problem()) { return 0; }
 5113:     my $partCount = $self->countParts();
 5114: 
 5115:     foreach my $part (@{$self->parts()}) {
 5116:         if ($part eq '0' && $partCount != 1) { next; }
 5117:         my $status = $self->status($part);
 5118:         # "If any of the parts are open, or have tries left (implies open),
 5119:         # and it is not "attempted" (manually graded problem), it is
 5120:         # not "complete"
 5121: 	if ($self->getCompletionStatus($part) == ATTEMPTED() ||
 5122:             $self->getCompletionStatus($part) == CREDIT_ATTEMPTED() ||
 5123: 	    $status == ANSWER_SUBMITTED() ) {
 5124: 	    # did this part already, as well as we can
 5125: 	    next;
 5126: 	}
 5127: 	if ($status == OPEN() || $status == TRIES_LEFT()) {
 5128: 	    return 1;
 5129: 	}
 5130:     }
 5131:         
 5132:     # If all the parts were complete, so was this problem.
 5133:     return 0;
 5134: }
 5135: 
 5136: =pod
 5137: 
 5138: =head2 Resource/Nav Map Navigation
 5139: 
 5140: =over 4
 5141: 
 5142: =item * B<getNext>():
 5143: 
 5144: Retreive an array of the possible next resources after this
 5145: one. Always returns an array, even in the one- or zero-element case.
 5146: 
 5147: =item * B<getPrevious>():
 5148: 
 5149: Retreive an array of the possible previous resources from this
 5150: one. Always returns an array, even in the one- or zero-element case.
 5151: 
 5152: =cut
 5153: 
 5154: sub getNext {
 5155:     my $self = shift;
 5156:     my @branches;
 5157:     my $to = $self->to();
 5158:     foreach my $branch ( split(/,/, $to) ) {
 5159:         my $choice = $self->{NAV_MAP}->getById($branch);
 5160:         #if (!$choice->condition()) { next; }
 5161:         my $next = $choice->goesto();
 5162:         $next = $self->{NAV_MAP}->getById($next);
 5163: 
 5164:         push @branches, $next;
 5165:     }
 5166:     return \@branches;
 5167: }
 5168: 
 5169: sub getPrevious {
 5170:     my $self = shift;
 5171:     my @branches;
 5172:     my $from = $self->from();
 5173:     foreach my $branch ( split /,/, $from) {
 5174:         my $choice = $self->{NAV_MAP}->getById($branch);
 5175:         my $prev = $choice->comesfrom();
 5176:         $prev = $self->{NAV_MAP}->getById($prev);
 5177: 
 5178:         push @branches, $prev;
 5179:     }
 5180:     return \@branches;
 5181: }
 5182: 
 5183: sub browsePriv {
 5184:     my $self = shift;
 5185:     if (defined($self->{BROWSE_PRIV})) {
 5186:         return $self->{BROWSE_PRIV};
 5187:     }
 5188: 
 5189:     $self->{BROWSE_PRIV} = &Apache::lonnet::allowed('bre',$self->src(),
 5190: 						    $self->symb());
 5191: }
 5192: 
 5193: =pod
 5194: 
 5195: =back
 5196: 
 5197: =cut
 5198: 
 5199: 1;
 5200: 
 5201: __END__
 5202: 
 5203: 

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