Annotation of loncom/interface/lonhelper.pm, revision 1.28

1.1       bowersj2    1: # The LearningOnline Network with CAPA
                      2: # .helper XML handler to implement the LON-CAPA helper
                      3: #
1.26      bowersj2    4: # $Id: lonhelper.pm,v 1.25 2003/05/08 19:52:43 bowersj2 Exp $
1.1       bowersj2    5: #
                      6: # Copyright Michigan State University Board of Trustees
                      7: #
                      8: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
                      9: #
                     10: # LON-CAPA is free software; you can redistribute it and/or modify
                     11: # it under the terms of the GNU General Public License as published by
                     12: # the Free Software Foundation; either version 2 of the License, or
                     13: # (at your option) any later version.
                     14: #
                     15: # LON-CAPA is distributed in the hope that it will be useful,
                     16: # but WITHOUT ANY WARRANTY; without even the implied warranty of
                     17: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                     18: # GNU General Public License for more details.
                     19: #
                     20: # You should have received a copy of the GNU General Public License
                     21: # along with LON-CAPA; if not, write to the Free Software
                     22: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
                     23: #
                     24: # /home/httpd/html/adm/gpl.txt
                     25: #
                     26: # http://www.lon-capa.org/
                     27: #
                     28: # (Page Handler
                     29: #
                     30: # (.helper handler
                     31: #
                     32: 
1.3       bowersj2   33: =pod
                     34: 
                     35: =head1 lonhelper - HTML Helper framework for LON-CAPA
                     36: 
                     37: Helpers, often known as "wizards", are well-established UI widgets that users
                     38: feel comfortable with. It can take a complicated multidimensional problem the
                     39: user has and turn it into a series of bite-sized one-dimensional questions.
                     40: 
                     41: For developers, helpers provide an easy way to bundle little bits of functionality
                     42: for the user, without having to write the tedious state-maintenence code.
                     43: 
                     44: Helpers are defined as XML documents, placed in the /home/httpd/html/adm/helpers 
                     45: directory and having the .helper file extension. For examples, see that directory.
                     46: 
                     47: All classes are in the Apache::lonhelper namespace.
                     48: 
                     49: =head2 lonhelper XML file format
                     50: 
                     51: A helper consists of a top-level <helper> tag which contains a series of states.
                     52: Each state contains one or more state elements, which are what the user sees, like
                     53: messages, resource selections, or date queries.
                     54: 
                     55: The helper tag is required to have one attribute, "title", which is the name
                     56: of the helper itself, such as "Parameter helper". 
                     57: 
                     58: =head2 State tags
                     59: 
                     60: State tags are required to have an attribute "name", which is the symbolic
1.7       bowersj2   61: name of the state and will not be directly seen by the user. The helper is
                     62: required to have one state named "START", which is the state the helper
1.5       bowersj2   63: will start with. By convention, this state should clearly describe what
1.3       bowersj2   64: the helper will do for the user, and may also include the first information
                     65: entry the user needs to do for the helper.
                     66: 
                     67: State tags are also required to have an attribute "title", which is the
                     68: human name of the state, and will be displayed as the header on top of 
                     69: the screen for the user.
                     70: 
                     71: =head2 Example Helper Skeleton
                     72: 
                     73: An example of the tags so far:
                     74: 
                     75:  <helper title="Example Helper">
                     76:    <state name="START" title="Demonstrating the Example Helper">
                     77:      <!-- notice this is the START state the wizard requires -->
                     78:      </state>
                     79:    <state name="GET_NAME" title="Enter Student Name">
                     80:      </state>
                     81:    </helper>
                     82: 
                     83: Of course this does nothing. In order for the wizard to do something, it is
                     84: necessary to put actual elements into the wizard. Documentation for each
                     85: of these elements follows.
                     86: 
1.13      bowersj2   87: =head2 Creating a Helper With Code, Not XML
                     88: 
                     89: In some situations, such as the printing wizard (see lonprintout.pm), 
                     90: writing the helper in XML would be too complicated, because of scope 
                     91: issues or the fact that the code actually outweighs the XML. It is
                     92: possible to create a helper via code, though it is a little odd.
                     93: 
                     94: Creating a helper via code is more like issuing commands to create
                     95: a helper then normal code writing. For instance, elements will automatically
                     96: be added to the last state created, so it's important to create the 
                     97: states in the correct order.
                     98: 
                     99: First, create a new helper:
                    100: 
                    101:  use Apache::lonhelper;
                    102: 
                    103:  my $helper = Apache::lonhelper::new->("Helper Title");
                    104: 
                    105: Next you'll need to manually add states to the helper:
                    106: 
                    107:  Apache::lonhelper::state->new("STATE_NAME", "State's Human Title");
                    108: 
                    109: You don't need to save a reference to it because all elements up until
                    110: the next state creation will automatically be added to this state.
                    111: 
                    112: Elements are created by populating the $paramHash in 
                    113: Apache::lonhelper::paramhash. To prevent namespace issues, retrieve 
                    114: a reference to that has with getParamHash:
                    115: 
                    116:  my $paramHash = Apache::lonhelper::getParamHash();
                    117: 
                    118: You will need to do this for each state you create.
                    119: 
                    120: Populate the $paramHash with the parameters for the element you wish
                    121: to add next; the easiest way to find out what those entries are is
                    122: to read the code. Some common ones are 'variable' to record the variable
                    123: to store the results in, and NEXTSTATE to record a next state transition.
                    124: 
                    125: Then create your element:
                    126: 
                    127:  $paramHash->{MESSAGETEXT} = "This is a message.";
                    128:  Apache::lonhelper::message->new();
                    129: 
                    130: The creation will take the $paramHash and bless it into a
                    131: Apache::lonhelper::message object. To create the next element, you need
                    132: to get a reference to the new, empty $paramHash:
                    133: 
                    134:  $paramHash = Apache::lonhelper::getParamHash();
                    135: 
                    136: and you can repeat creating elements that way. You can add states
                    137: and elements as needed.
                    138: 
                    139: See lonprintout.pm, subroutine printHelper for an example of this, where
                    140: we dynamically add some states to prevent security problems, for instance.
                    141: 
                    142: Normally the machinery in the XML format is sufficient; dynamically 
                    143: adding states can easily be done by wrapping the state in a <condition>
                    144: tag. This should only be used when the code dominates the XML content,
                    145: the code is so complicated that it is difficult to get access to
                    146: all of the information you need because of scoping issues, or so much
                    147: of the information used is persistent because would-be <exec> or 
                    148: <eval> blocks that using the {DATA} mechanism results in hard-to-read
                    149: and -maintain code.
                    150: 
                    151: It is possible to do some of the work with an XML fragment parsed by
1.17      bowersj2  152: lonxml; again, see lonprintout.pm for an example. In that case it is 
                    153: imperative that you call B<Apache::lonhelper::registerHelperTags()>
                    154: before parsing XML fragments and B<Apache::lonhelper::unregisterHelperTags()>
                    155: when you are done. See lonprintout.pm for examples of this usage in the
                    156: printHelper subroutine.
1.13      bowersj2  157: 
1.3       bowersj2  158: =cut
                    159: 
1.1       bowersj2  160: package Apache::lonhelper;
1.2       bowersj2  161: use Apache::Constants qw(:common);
                    162: use Apache::File;
1.3       bowersj2  163: use Apache::lonxml;
1.2       bowersj2  164: 
1.7       bowersj2  165: # Register all the tags with the helper, so the helper can 
                    166: # push and pop them
                    167: 
                    168: my @helperTags;
                    169: 
                    170: sub register {
                    171:     my ($namespace, @tags) = @_;
                    172: 
                    173:     for my $tag (@tags) {
                    174:         push @helperTags, [$namespace, $tag];
                    175:     }
                    176: }
                    177: 
1.2       bowersj2  178: BEGIN {
1.7       bowersj2  179:     Apache::lonxml::register('Apache::lonhelper', 
                    180:                              ('helper'));
                    181:       register('Apache::lonhelper', ('state'));
1.2       bowersj2  182: }
                    183: 
1.7       bowersj2  184: # Since all helpers are only three levels deep (helper tag, state tag, 
1.3       bowersj2  185: # substate type), it's easier and more readble to explicitly track 
                    186: # those three things directly, rather then futz with the tag stack 
                    187: # every time.
                    188: my $helper;
                    189: my $state;
                    190: my $substate;
1.4       bowersj2  191: # To collect parameters, the contents of the subtags are collected
                    192: # into this paramHash, then passed to the element object when the 
                    193: # end of the element tag is located.
                    194: my $paramHash; 
1.2       bowersj2  195: 
1.25      bowersj2  196: # Note from Jeremy 5-8-2003: It is *vital* that the real handler be called
                    197: # as a subroutine from the handler, or very mysterious things might happen.
                    198: # I don't know exactly why, but it seems that the scope where the Apache
                    199: # server enters the perl handler is treated differently from the rest of
                    200: # the handler. This also seems to manifest itself in the debugger as entering
                    201: # the perl handler in seemingly random places (sometimes it starts in the
                    202: # compiling phase, sometimes in the handler execution phase where it runs
                    203: # the code and stepping into the "1;" the module ends with goes into the handler,
                    204: # sometimes starting directly with the handler); I think the cause is related.
                    205: # In the debugger, this means that breakpoints are ignored until you step into
                    206: # a function and get out of what must be a "faked up scope" in the Apache->
                    207: # mod_perl connection. In this code, it was manifesting itself in the existence
                    208: # of two seperate file-scoped $helper variables, one set to the value of the
                    209: # helper in the helper constructor, and one referenced by the handler on the
                    210: # "$helper->process()" line. The second was therefore never set, and was still
                    211: # undefined when I tried to call process on it.
                    212: # By pushing the "real handler" down into the "real scope", everybody except the 
                    213: # actual handler function directly below this comment gets the same $helper and
                    214: # everybody is happy.
                    215: # The upshot of all of this is that for safety when a handler is  using 
                    216: # file-scoped variables in LON-CAPA, the handler should be pushed down one 
                    217: # call level, as I do here, to ensure that the top-level handler function does
                    218: # not get a different file scope from the rest of the code.
                    219: sub handler {
                    220:     my $r = shift;
                    221:     return real_handler($r);
                    222: }
                    223: 
1.13      bowersj2  224: # For debugging purposes, one can send a second parameter into this
                    225: # function, the 'uri' of the helper you wish to have rendered, and
                    226: # call this from other handlers.
1.25      bowersj2  227: sub real_handler {
1.3       bowersj2  228:     my $r = shift;
1.13      bowersj2  229:     my $uri = shift;
                    230:     if (!defined($uri)) { $uri = $r->uri(); }
                    231:     $ENV{'request.uri'} = $uri;
                    232:     my $filename = '/home/httpd/html' . $uri;
1.2       bowersj2  233:     my $fh = Apache::File->new($filename);
                    234:     my $file;
1.3       bowersj2  235:     read $fh, $file, 100000000;
                    236: 
1.27      bowersj2  237: 
1.3       bowersj2  238:     # Send header, don't cache this page
                    239:     if ($r->header_only) {
                    240:         if ($ENV{'browser.mathml'}) {
                    241:             $r->content_type('text/xml');
                    242:         } else {
                    243:             $r->content_type('text/html');
                    244:         }
                    245:         $r->send_http_header;
                    246:         return OK;
                    247:     }
                    248:     if ($ENV{'browser.mathml'}) {
                    249:         $r->content_type('text/xml');
                    250:     } else {
                    251:         $r->content_type('text/html');
                    252:     }
                    253:     $r->send_http_header;
                    254:     $r->rflush();
1.2       bowersj2  255: 
1.3       bowersj2  256:     # Discard result, we just want the objects that get created by the
                    257:     # xml parsing
                    258:     &Apache::lonxml::xmlparse($r, 'helper', $file);
1.2       bowersj2  259: 
1.13      bowersj2  260:     $helper->process();
                    261: 
1.3       bowersj2  262:     $r->print($helper->display());
1.7       bowersj2  263:    return OK;
1.2       bowersj2  264: }
                    265: 
1.13      bowersj2  266: sub registerHelperTags {
                    267:     for my $tagList (@helperTags) {
                    268:         Apache::lonxml::register($tagList->[0], $tagList->[1]);
                    269:     }
                    270: }
                    271: 
                    272: sub unregisterHelperTags {
                    273:     for my $tagList (@helperTags) {
                    274:         Apache::lonxml::deregister($tagList->[0], $tagList->[1]);
                    275:     }
                    276: }
                    277: 
1.2       bowersj2  278: sub start_helper {
                    279:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                    280: 
                    281:     if ($target ne 'helper') {
                    282:         return '';
                    283:     }
1.7       bowersj2  284: 
1.13      bowersj2  285:     registerHelperTags();
                    286: 
                    287:     Apache::lonhelper::helper->new($token->[2]{'title'});
1.4       bowersj2  288:     return '';
1.2       bowersj2  289: }
                    290: 
                    291: sub end_helper {
                    292:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                    293:     
1.3       bowersj2  294:     if ($target ne 'helper') {
                    295:         return '';
                    296:     }
1.7       bowersj2  297: 
1.13      bowersj2  298:     unregisterHelperTags();
1.7       bowersj2  299: 
1.4       bowersj2  300:     return '';
1.2       bowersj2  301: }
1.1       bowersj2  302: 
1.3       bowersj2  303: sub start_state {
                    304:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                    305: 
                    306:     if ($target ne 'helper') {
                    307:         return '';
                    308:     }
                    309: 
1.13      bowersj2  310:     Apache::lonhelper::state->new($token->[2]{'name'},
                    311:                                   $token->[2]{'title'});
1.3       bowersj2  312:     return '';
                    313: }
                    314: 
1.13      bowersj2  315: # Use this to get the param hash from other files.
                    316: sub getParamHash {
                    317:     return $paramHash;
                    318: }
                    319: 
                    320: # Use this to get the helper, if implementing elements in other files
                    321: # (like lonprintout.pm)
                    322: sub getHelper {
                    323:     return $helper;
                    324: }
                    325: 
1.3       bowersj2  326: # don't need this, so ignore it
                    327: sub end_state {
                    328:     return '';
                    329: }
                    330: 
1.1       bowersj2  331: 1;
                    332: 
1.3       bowersj2  333: package Apache::lonhelper::helper;
                    334: 
                    335: use Digest::MD5 qw(md5_hex);
                    336: use HTML::Entities;
                    337: use Apache::loncommon;
                    338: use Apache::File;
                    339: 
                    340: sub new {
                    341:     my $proto = shift;
                    342:     my $class = ref($proto) || $proto;
                    343:     my $self = {};
                    344: 
                    345:     $self->{TITLE} = shift;
                    346:     
                    347:     # If there is a state from the previous form, use that. If there is no
                    348:     # state, use the start state parameter.
                    349:     if (defined $ENV{"form.CURRENT_STATE"})
                    350:     {
                    351: 	$self->{STATE} = $ENV{"form.CURRENT_STATE"};
                    352:     }
                    353:     else
                    354:     {
                    355: 	$self->{STATE} = "START";
                    356:     }
                    357: 
                    358:     $self->{TOKEN} = $ENV{'form.TOKEN'};
                    359:     # If a token was passed, we load that in. Otherwise, we need to create a 
                    360:     # new storage file
                    361:     # Tried to use standard Tie'd hashes, but you can't seem to take a 
                    362:     # reference to a tied hash and write to it. I'd call that a wart.
                    363:     if ($self->{TOKEN}) {
                    364:         # Validate the token before trusting it
                    365:         if ($self->{TOKEN} !~ /^[a-f0-9]{32}$/) {
                    366:             # Not legit. Return nothing and let all hell break loose.
                    367:             # User shouldn't be doing that!
                    368:             return undef;
                    369:         }
                    370: 
                    371:         # Get the hash.
                    372:         $self->{FILENAME} = $Apache::lonnet::tmpdir . md5_hex($self->{TOKEN}); # Note the token is not the literal file
                    373:         
                    374:         my $file = Apache::File->new($self->{FILENAME});
                    375:         my $contents = <$file>;
1.5       bowersj2  376: 
                    377:         # Now load in the contents
                    378:         for my $value (split (/&/, $contents)) {
                    379:             my ($name, $value) = split(/=/, $value);
                    380:             $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
                    381:             $self->{VARS}->{$name} = $value;
                    382:         }
                    383: 
1.3       bowersj2  384:         $file->close();
                    385:     } else {
                    386:         # Only valid if we're just starting.
                    387:         if ($self->{STATE} ne 'START') {
                    388:             return undef;
                    389:         }
                    390:         # Must create the storage
                    391:         $self->{TOKEN} = md5_hex($ENV{'user.name'} . $ENV{'user.domain'} .
                    392:                                  time() . rand());
                    393:         $self->{FILENAME} = $Apache::lonnet::tmpdir . md5_hex($self->{TOKEN});
                    394:     }
                    395: 
                    396:     # OK, we now have our persistent storage.
                    397: 
                    398:     if (defined $ENV{"form.RETURN_PAGE"})
                    399:     {
                    400: 	$self->{RETURN_PAGE} = $ENV{"form.RETURN_PAGE"};
                    401:     }
                    402:     else
                    403:     {
                    404: 	$self->{RETURN_PAGE} = $ENV{REFERER};
                    405:     }
                    406: 
                    407:     $self->{STATES} = {};
                    408:     $self->{DONE} = 0;
                    409: 
1.9       bowersj2  410:     # Used by various helpers for various things; see lonparm.helper
                    411:     # for an example.
                    412:     $self->{DATA} = {};
                    413: 
1.13      bowersj2  414:     $helper = $self;
                    415: 
                    416:     # Establish the $paramHash
                    417:     $paramHash = {};
                    418: 
1.3       bowersj2  419:     bless($self, $class);
                    420:     return $self;
                    421: }
                    422: 
                    423: # Private function; returns a string to construct the hidden fields
                    424: # necessary to have the helper track state.
                    425: sub _saveVars {
                    426:     my $self = shift;
                    427:     my $result = "";
                    428:     $result .= '<input type="hidden" name="CURRENT_STATE" value="' .
                    429:         HTML::Entities::encode($self->{STATE}) . "\" />\n";
                    430:     $result .= '<input type="hidden" name="TOKEN" value="' .
                    431:         $self->{TOKEN} . "\" />\n";
                    432:     $result .= '<input type="hidden" name="RETURN_PAGE" value="' .
                    433:         HTML::Entities::encode($self->{RETURN_PAGE}) . "\" />\n";
                    434: 
                    435:     return $result;
                    436: }
                    437: 
                    438: # Private function: Create the querystring-like representation of the stored
                    439: # data to write to disk.
                    440: sub _varsInFile {
                    441:     my $self = shift;
                    442:     my @vars = ();
                    443:     for my $key (keys %{$self->{VARS}}) {
                    444:         push @vars, &Apache::lonnet::escape($key) . '=' .
                    445:             &Apache::lonnet::escape($self->{VARS}->{$key});
                    446:     }
                    447:     return join ('&', @vars);
                    448: }
                    449: 
1.5       bowersj2  450: # Use this to declare variables.
                    451: # FIXME: Document this
                    452: sub declareVar {
                    453:     my $self = shift;
                    454:     my $var = shift;
                    455: 
                    456:     if (!defined($self->{VARS}->{$var})) {
                    457:         $self->{VARS}->{$var} = '';
                    458:     }
                    459: 
                    460:     my $envname = 'form.' . $var . '.forminput';
                    461:     if (defined($ENV{$envname})) {
1.28    ! bowersj2  462:         if (ref($ENV{$envname})) {
        !           463:             $self->{VARS}->{$var} = join('|||', @{$ENV{$envname}});
        !           464:         } else {
        !           465:             $self->{VARS}->{$var} = $ENV{$envname};
        !           466:         }
1.5       bowersj2  467:     }
                    468: }
                    469: 
1.3       bowersj2  470: sub changeState {
                    471:     my $self = shift;
                    472:     $self->{STATE} = shift;
                    473: }
                    474: 
                    475: sub registerState {
                    476:     my $self = shift;
                    477:     my $state = shift;
                    478: 
                    479:     my $stateName = $state->name();
                    480:     $self->{STATES}{$stateName} = $state;
                    481: }
                    482: 
1.13      bowersj2  483: sub process {
1.3       bowersj2  484:     my $self = shift;
                    485: 
                    486:     # Phase 1: Post processing for state of previous screen (which is actually
                    487:     # the "current state" in terms of the helper variables), if it wasn't the 
                    488:     # beginning state.
                    489:     if ($self->{STATE} ne "START" || $ENV{"form.SUBMIT"} eq "Next ->") {
                    490: 	my $prevState = $self->{STATES}{$self->{STATE}};
1.13      bowersj2  491:         $prevState->postprocess();
1.3       bowersj2  492:     }
                    493:     
                    494:     # Note, to handle errors in a state's input that a user must correct,
                    495:     # do not transition in the postprocess, and force the user to correct
                    496:     # the error.
                    497: 
                    498:     # Phase 2: Preprocess current state
                    499:     my $startState = $self->{STATE};
1.17      bowersj2  500:     my $state = $self->{STATES}->{$startState};
1.3       bowersj2  501:     
1.13      bowersj2  502:     # For debugging, print something here to determine if you're going
                    503:     # to an undefined state.
1.3       bowersj2  504:     if (!defined($state)) {
1.13      bowersj2  505:         return;
1.3       bowersj2  506:     }
                    507:     $state->preprocess();
                    508: 
                    509:     # Phase 3: While the current state is different from the previous state,
                    510:     # keep processing.
1.17      bowersj2  511:     while ( $startState ne $self->{STATE} && 
                    512:             defined($self->{STATES}->{$self->{STATE}}) )
1.3       bowersj2  513:     {
                    514: 	$startState = $self->{STATE};
1.17      bowersj2  515: 	$state = $self->{STATES}->{$startState};
1.3       bowersj2  516: 	$state->preprocess();
                    517:     }
                    518: 
1.13      bowersj2  519:     return;
                    520: } 
                    521: 
                    522: # 1: Do the post processing for the previous state.
                    523: # 2: Do the preprocessing for the current state.
                    524: # 3: Check to see if state changed, if so, postprocess current and move to next.
                    525: #    Repeat until state stays stable.
                    526: # 4: Render the current state to the screen as an HTML page.
                    527: sub display {
                    528:     my $self = shift;
                    529: 
                    530:     my $state = $self->{STATES}{$self->{STATE}};
                    531: 
                    532:     my $result = "";
                    533: 
1.17      bowersj2  534:     if (!defined($state)) {
                    535:         $result = "<font color='#ff0000'>Error: state '$state' not defined!</font>";
                    536:         return $result;
                    537:     }
                    538: 
1.3       bowersj2  539:     # Phase 4: Display.
                    540:     my $stateTitle = $state->title();
                    541:     my $bodytag = &Apache::loncommon::bodytag("$self->{TITLE}",'','');
                    542: 
                    543:     $result .= <<HEADER;
                    544: <html>
                    545:     <head>
                    546:         <title>LON-CAPA Helper: $self->{TITLE}</title>
                    547:     </head>
                    548:     $bodytag
                    549: HEADER
1.28    ! bowersj2  550:     if (!$state->overrideForm()) { $result.="<form name='helpform' method='POST'>"; }
1.3       bowersj2  551:     $result .= <<HEADER;
                    552:         <table border="0"><tr><td>
                    553:         <h2><i>$stateTitle</i></h2>
                    554: HEADER
                    555: 
                    556:     if (!$state->overrideForm()) {
                    557:         $result .= $self->_saveVars();
                    558:     }
                    559:     $result .= $state->render() . "<p>&nbsp;</p>";
                    560: 
                    561:     if (!$state->overrideForm()) {
                    562:         $result .= '<center>';
                    563:         if ($self->{STATE} ne $self->{START_STATE}) {
                    564:             #$result .= '<input name="SUBMIT" type="submit" value="&lt;- Previous" />&nbsp;&nbsp;';
                    565:         }
                    566:         if ($self->{DONE}) {
                    567:             my $returnPage = $self->{RETURN_PAGE};
                    568:             $result .= "<a href=\"$returnPage\">End Helper</a>";
                    569:         }
                    570:         else {
                    571:             $result .= '<input name="back" type="button" ';
                    572:             $result .= 'value="&lt;- Previous" onclick="history.go(-1)" /> ';
                    573:             $result .= '<input name="SUBMIT" type="submit" value="Next -&gt;" />';
                    574:         }
                    575:         $result .= "</center>\n";
                    576:     }
                    577: 
1.13      bowersj2  578:     #foreach my $key (keys %{$self->{VARS}}) {
                    579:     #    $result .= "|$key| -> " . $self->{VARS}->{$key} . "<br />";
                    580:     #}
1.5       bowersj2  581: 
1.3       bowersj2  582:     $result .= <<FOOTER;
                    583:               </td>
                    584:             </tr>
                    585:           </table>
                    586:         </form>
                    587:     </body>
                    588: </html>
                    589: FOOTER
                    590: 
                    591:     # Handle writing out the vars to the file
                    592:     my $file = Apache::File->new('>'.$self->{FILENAME});
                    593:     print $file $self->_varsInFile();
                    594: 
                    595:     return $result;
                    596: }
                    597: 
                    598: 1;
                    599: 
                    600: package Apache::lonhelper::state;
                    601: 
                    602: # States bundle things together and are responsible for compositing the
1.4       bowersj2  603: # various elements together. It is not generally necessary for users to
                    604: # use the state object directly, so it is not perldoc'ed.
                    605: 
                    606: # Basically, all the states do is pass calls to the elements and aggregate
                    607: # the results.
1.3       bowersj2  608: 
                    609: sub new {
                    610:     my $proto = shift;
                    611:     my $class = ref($proto) || $proto;
                    612:     my $self = {};
                    613: 
                    614:     $self->{NAME} = shift;
                    615:     $self->{TITLE} = shift;
                    616:     $self->{ELEMENTS} = [];
                    617: 
                    618:     bless($self, $class);
                    619: 
                    620:     $helper->registerState($self);
                    621: 
1.13      bowersj2  622:     $state = $self;
                    623: 
1.3       bowersj2  624:     return $self;
                    625: }
                    626: 
                    627: sub name {
                    628:     my $self = shift;
                    629:     return $self->{NAME};
                    630: }
                    631: 
                    632: sub title {
                    633:     my $self = shift;
                    634:     return $self->{TITLE};
                    635: }
                    636: 
1.4       bowersj2  637: sub preprocess {
                    638:     my $self = shift;
                    639:     for my $element (@{$self->{ELEMENTS}}) {
                    640:         $element->preprocess();
                    641:     }
                    642: }
                    643: 
1.6       bowersj2  644: # FIXME: Document that all postprocesses must return a true value or
                    645: # the state transition will be overridden
1.4       bowersj2  646: sub postprocess {
                    647:     my $self = shift;
1.6       bowersj2  648: 
                    649:     # Save the state so we can roll it back if we need to.
                    650:     my $originalState = $helper->{STATE};
                    651:     my $everythingSuccessful = 1;
                    652: 
1.4       bowersj2  653:     for my $element (@{$self->{ELEMENTS}}) {
1.6       bowersj2  654:         my $result = $element->postprocess();
                    655:         if (!$result) { $everythingSuccessful = 0; }
                    656:     }
                    657: 
                    658:     # If not all the postprocesses were successful, override
                    659:     # any state transitions that may have occurred. It is the
                    660:     # responsibility of the states to make sure they have 
                    661:     # error handling in that case.
                    662:     if (!$everythingSuccessful) {
                    663:         $helper->{STATE} = $originalState;
1.4       bowersj2  664:     }
                    665: }
                    666: 
1.13      bowersj2  667: # Override the form if any element wants to.
                    668: # two elements overriding the form will make a mess, but that should
                    669: # be considered helper author error ;-)
1.4       bowersj2  670: sub overrideForm {
1.13      bowersj2  671:     my $self = shift;
                    672:     for my $element (@{$self->{ELEMENTS}}) {
                    673:         if ($element->overrideForm()) {
                    674:             return 1;
                    675:         }
                    676:     }
1.4       bowersj2  677:     return 0;
                    678: }
                    679: 
                    680: sub addElement {
                    681:     my $self = shift;
                    682:     my $element = shift;
                    683:     
                    684:     push @{$self->{ELEMENTS}}, $element;
                    685: }
                    686: 
1.28    ! bowersj2  687: use Data::Dumper;
1.4       bowersj2  688: sub render {
                    689:     my $self = shift;
                    690:     my @results = ();
                    691: 
                    692:     for my $element (@{$self->{ELEMENTS}}) {
                    693:         push @results, $element->render();
                    694:     }
1.28    ! bowersj2  695: 
1.4       bowersj2  696:     return join("\n", @results);
                    697: }
                    698: 
                    699: 1;
                    700: 
                    701: package Apache::lonhelper::element;
                    702: # Support code for elements
                    703: 
                    704: =pod
                    705: 
                    706: =head2 Element Base Class
                    707: 
1.28    ! bowersj2  708: The Apache::lonhelper::element base class provides support for elements
        !           709: and defines some generally useful tags for use in elements.
1.4       bowersj2  710: 
1.25      bowersj2  711: B<finalcode tag>
                    712: 
                    713: Each element can contain a "finalcode" tag that, when the special FINAL
                    714: helper state is used, will be executed, surrounded by "sub { my $helper = shift;"
                    715: and "}". It is expected to return a string describing what it did, which 
                    716: may be an empty string. See course initialization helper for an example. This is
                    717: generally intended for helpers like the course initialization helper, which consist
                    718: of several panels, each of which is performing some sort of bite-sized functionality.
                    719: 
                    720: B<defaultvalue tag>
                    721: 
                    722: Each element that accepts user input can contain a "defaultvalue" tag that,
                    723: when surrounded by "sub { my $helper = shift; my $state = shift; " and "}",
                    724: will form a subroutine that when called will provide a default value for
                    725: the element. How this value is interpreted by the element is specific to
                    726: the element itself, and possibly the settings the element has (such as 
                    727: multichoice vs. single choice for <choices> tags). 
                    728: 
                    729: This is also intended for things like the course initialization wizard, where the
                    730: user is setting various parameters. By correctly grabbing current settings 
                    731: and including them into the helper, it allows the user to come back to the
                    732: helper later and re-execute it, without needing to worry about overwriting
                    733: some setting accidentally.
                    734: 
                    735: Again, see the course initialization helper for examples.
                    736: 
1.4       bowersj2  737: =cut
                    738: 
1.5       bowersj2  739: BEGIN {
1.7       bowersj2  740:     &Apache::lonhelper::register('Apache::lonhelper::element',
1.25      bowersj2  741:                                  ('nextstate', 'finalcode',
                    742:                                   'defaultvalue'));
1.5       bowersj2  743: }
                    744: 
1.4       bowersj2  745: # Because we use the param hash, this is often a sufficent
                    746: # constructor
                    747: sub new {
                    748:     my $proto = shift;
                    749:     my $class = ref($proto) || $proto;
                    750:     my $self = $paramHash;
                    751:     bless($self, $class);
                    752: 
                    753:     $self->{PARAMS} = $paramHash;
                    754:     $self->{STATE} = $state;
                    755:     $state->addElement($self);
                    756:     
                    757:     # Ensure param hash is not reused
                    758:     $paramHash = {};
                    759: 
                    760:     return $self;
                    761: }   
                    762: 
1.5       bowersj2  763: sub start_nextstate {
                    764:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                    765: 
                    766:     if ($target ne 'helper') {
                    767:         return '';
                    768:     }
                    769:     
                    770:     $paramHash->{NEXTSTATE} = &Apache::lonxml::get_all_text('/nextstate',
                    771:                                                              $parser);
                    772:     return '';
                    773: }
                    774: 
                    775: sub end_nextstate { return ''; }
                    776: 
1.25      bowersj2  777: sub start_finalcode {
                    778:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                    779: 
                    780:     if ($target ne 'helper') {
                    781:         return '';
                    782:     }
                    783:     
                    784:     $paramHash->{FINAL_CODE} = &Apache::lonxml::get_all_text('/finalcode',
                    785:                                                              $parser);
                    786:     return '';
                    787: }
                    788: 
                    789: sub end_finalcode { return ''; }
                    790: 
                    791: sub start_defaultvalue {
                    792:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                    793: 
                    794:     if ($target ne 'helper') {
                    795:         return '';
                    796:     }
                    797:     
                    798:     $paramHash->{DEFAULT_VALUE} = &Apache::lonxml::get_all_text('/defaultvalue',
                    799:                                                              $parser);
                    800:     $paramHash->{DEFAULT_VALUE} = 'sub { my $helper = shift; my $state = shift;' .
                    801:         $paramHash->{DEFAULT_VALUE} . '}';
                    802:     return '';
                    803: }
                    804: 
                    805: sub end_defaultvalue { return ''; }
                    806: 
1.4       bowersj2  807: sub preprocess {
                    808:     return 1;
                    809: }
                    810: 
                    811: sub postprocess {
                    812:     return 1;
                    813: }
                    814: 
                    815: sub render {
                    816:     return '';
                    817: }
                    818: 
1.13      bowersj2  819: sub overrideForm {
                    820:     return 0;
                    821: }
                    822: 
1.4       bowersj2  823: 1;
                    824: 
                    825: package Apache::lonhelper::message;
                    826: 
                    827: =pod
                    828: 
                    829: =head2 Element: message
                    830: 
                    831: Message elements display the contents of their <message_text> tags, and
1.5       bowersj2  832: transition directly to the state in the <nextstate> tag. Example:
1.4       bowersj2  833: 
                    834:  <message>
1.5       bowersj2  835:    <nextstate>GET_NAME</nextstate>
1.4       bowersj2  836:    <message_text>This is the <b>message</b> the user will see, 
                    837:                  <i>HTML allowed</i>.</message_text>
                    838:    </message>
                    839: 
1.5       bowersj2  840: This will display the HTML message and transition to the <nextstate> if
1.7       bowersj2  841: given. The HTML will be directly inserted into the helper, so if you don't
1.4       bowersj2  842: want text to run together, you'll need to manually wrap the <message_text>
                    843: in <p> tags, or whatever is appropriate for your HTML.
                    844: 
1.5       bowersj2  845: Message tags do not add in whitespace, so if you want it, you'll need to add
                    846: it into states. This is done so you can inline some elements, such as 
                    847: the <date> element, right between two messages, giving the appearence that 
                    848: the <date> element appears inline. (Note the elements can not be embedded
                    849: within each other.)
                    850: 
1.4       bowersj2  851: This is also a good template for creating your own new states, as it has
                    852: very little code beyond the state template.
                    853: 
                    854: =cut
                    855: 
                    856: no strict;
                    857: @ISA = ("Apache::lonhelper::element");
                    858: use strict;
                    859: 
                    860: BEGIN {
1.7       bowersj2  861:     &Apache::lonhelper::register('Apache::lonhelper::message',
1.10      bowersj2  862:                               ('message'));
1.3       bowersj2  863: }
                    864: 
1.5       bowersj2  865: sub new {
                    866:     my $ref = Apache::lonhelper::element->new();
                    867:     bless($ref);
                    868: }
1.4       bowersj2  869: 
                    870: # CONSTRUCTION: Construct the message element from the XML
                    871: sub start_message {
                    872:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                    873: 
                    874:     if ($target ne 'helper') {
                    875:         return '';
                    876:     }
1.10      bowersj2  877: 
                    878:     $paramHash->{MESSAGE_TEXT} = &Apache::lonxml::get_all_text('/message',
                    879:                                                                $parser);
                    880: 
                    881:     if (defined($token->[2]{'nextstate'})) {
                    882:         $paramHash->{NEXTSTATE} = $token->[2]{'nextstate'};
                    883:     }
1.4       bowersj2  884:     return '';
1.3       bowersj2  885: }
                    886: 
1.10      bowersj2  887: sub end_message {
1.4       bowersj2  888:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                    889: 
                    890:     if ($target ne 'helper') {
                    891:         return '';
                    892:     }
1.10      bowersj2  893:     Apache::lonhelper::message->new();
                    894:     return '';
1.5       bowersj2  895: }
                    896: 
                    897: sub render {
                    898:     my $self = shift;
                    899: 
                    900:     return $self->{MESSAGE_TEXT};
                    901: }
                    902: # If a NEXTSTATE was given, switch to it
                    903: sub postprocess {
                    904:     my $self = shift;
                    905:     if (defined($self->{NEXTSTATE})) {
                    906:         $helper->changeState($self->{NEXTSTATE});
                    907:     }
1.6       bowersj2  908: 
                    909:     return 1;
1.5       bowersj2  910: }
                    911: 1;
                    912: 
                    913: package Apache::lonhelper::choices;
                    914: 
                    915: =pod
                    916: 
                    917: =head2 Element: choices
                    918: 
                    919: Choice states provide a single choice to the user as a text selection box.
                    920: A "choice" is two pieces of text, one which will be displayed to the user
                    921: (the "human" value), and one which will be passed back to the program
                    922: (the "computer" value). For instance, a human may choose from a list of
                    923: resources on disk by title, while your program wants the file name.
                    924: 
                    925: <choices> takes an attribute "variable" to control which helper variable
                    926: the result is stored in.
                    927: 
                    928: <choices> takes an attribute "multichoice" which, if set to a true
                    929: value, will allow the user to select multiple choices.
                    930: 
1.26      bowersj2  931: <choices> takes an attribute "allowempty" which, if set to a true 
                    932: value, will allow the user to select none of the choices without raising
                    933: an error message.
                    934: 
1.5       bowersj2  935: B<SUB-TAGS>
                    936: 
                    937: <choices> can have the following subtags:
                    938: 
                    939: =over 4
                    940: 
                    941: =item * <nextstate>state_name</nextstate>: If given, this will cause the
                    942:       choice element to transition to the given state after executing. If
                    943:       this is used, do not pass nextstates to the <choice> tag.
                    944: 
                    945: =item * <choice />: If the choices are static,
                    946:       this element will allow you to specify them. Each choice
                    947:       contains  attribute, "computer", as described above. The
                    948:       content of the tag will be used as the human label.
                    949:       For example,  
                    950:       <choice computer='234-12-7312'>Bobby McDormik</choice>.
                    951: 
1.13      bowersj2  952:       <choice> can take a parameter "eval", which if set to
                    953:       a true value, will cause the contents of the tag to be
                    954:       evaluated as it would be in an <eval> tag; see <eval> tag
                    955:       below.
                    956: 
1.5       bowersj2  957: <choice> may optionally contain a 'nextstate' attribute, which
                    958: will be the state transisitoned to if the choice is made, if
                    959: the choice is not multichoice.
                    960: 
                    961: =back
                    962: 
                    963: To create the choices programmatically, either wrap the choices in 
                    964: <condition> tags (prefered), or use an <exec> block inside the <choice>
                    965: tag. Store the choices in $state->{CHOICES}, which is a list of list
                    966: references, where each list has three strings. The first is the human
                    967: name, the second is the computer name. and the third is the option
                    968: next state. For example:
                    969: 
                    970:  <exec>
                    971:     for (my $i = 65; $i < 65 + 26; $i++) {
                    972:         push @{$state->{CHOICES}}, [chr($i), $i, 'next'];
                    973:     }
                    974:  </exec>
                    975: 
                    976: This will allow the user to select from the letters A-Z (in ASCII), while
                    977: passing the ASCII value back into the helper variables, and the state
                    978: will in all cases transition to 'next'.
                    979: 
                    980: You can mix and match methods of creating choices, as long as you always 
                    981: "push" onto the choice list, rather then wiping it out. (You can even 
                    982: remove choices programmatically, but that would probably be bad form.)
                    983: 
1.25      bowersj2  984: B<defaultvalue support>
                    985: 
                    986: Choices supports default values both in multichoice and single choice mode.
                    987: In single choice mode, have the defaultvalue tag's function return the 
                    988: computer value of the box you want checked. If the function returns a value
                    989: that does not correspond to any of the choices, the default behavior of selecting
                    990: the first choice will be preserved.
                    991: 
                    992: For multichoice, return a string with the computer values you want checked,
                    993: delimited by triple pipes. Note this matches how the result of the <choices>
                    994: tag is stored in the {VARS} hash.
                    995: 
1.5       bowersj2  996: =cut
                    997: 
                    998: no strict;
                    999: @ISA = ("Apache::lonhelper::element");
                   1000: use strict;
                   1001: 
                   1002: BEGIN {
1.7       bowersj2 1003:     &Apache::lonhelper::register('Apache::lonhelper::choices',
1.5       bowersj2 1004:                               ('choice', 'choices'));
                   1005: }
                   1006: 
                   1007: sub new {
                   1008:     my $ref = Apache::lonhelper::element->new();
                   1009:     bless($ref);
                   1010: }
                   1011: 
                   1012: # CONSTRUCTION: Construct the message element from the XML
                   1013: sub start_choices {
                   1014:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1015: 
                   1016:     if ($target ne 'helper') {
                   1017:         return '';
                   1018:     }
                   1019: 
                   1020:     # Need to initialize the choices list, so everything can assume it exists
1.24      sakharuk 1021:     $paramHash->{'variable'} = $token->[2]{'variable'} if (!defined($paramHash->{'variable'}));
1.5       bowersj2 1022:     $helper->declareVar($paramHash->{'variable'});
                   1023:     $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
1.26      bowersj2 1024:     $paramHash->{'allowempty'} = $token->[2]{'allowempty'};
1.5       bowersj2 1025:     $paramHash->{CHOICES} = [];
                   1026:     return '';
                   1027: }
                   1028: 
                   1029: sub end_choices {
                   1030:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1031: 
                   1032:     if ($target ne 'helper') {
                   1033:         return '';
                   1034:     }
                   1035:     Apache::lonhelper::choices->new();
                   1036:     return '';
                   1037: }
                   1038: 
                   1039: sub start_choice {
                   1040:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1041: 
                   1042:     if ($target ne 'helper') {
                   1043:         return '';
                   1044:     }
                   1045: 
                   1046:     my $computer = $token->[2]{'computer'};
                   1047:     my $human = &Apache::lonxml::get_all_text('/choice',
                   1048:                                               $parser);
                   1049:     my $nextstate = $token->[2]{'nextstate'};
1.13      bowersj2 1050:     my $evalFlag = $token->[2]{'eval'};
                   1051:     push @{$paramHash->{CHOICES}}, [$human, $computer, $nextstate, 
                   1052:                                     $evalFlag];
1.5       bowersj2 1053:     return '';
                   1054: }
                   1055: 
                   1056: sub end_choice {
                   1057:     return '';
                   1058: }
                   1059: 
                   1060: sub render {
                   1061:     # START HERE: Replace this with correct choices code.
                   1062:     my $self = shift;
                   1063:     my $var = $self->{'variable'};
                   1064:     my $buttons = '';
                   1065:     my $result = '';
                   1066: 
                   1067:     if ($self->{'multichoice'}) {
1.6       bowersj2 1068:         $result .= <<SCRIPT;
1.5       bowersj2 1069: <script>
1.18      bowersj2 1070:     function checkall(value, checkName) {
1.15      bowersj2 1071: 	for (i=0; i<document.forms.helpform.elements.length; i++) {
1.18      bowersj2 1072:             ele = document.forms.helpform.elements[i];
                   1073:             if (ele.name == checkName + '.forminput') {
                   1074:                 document.forms.helpform.elements[i].checked=value;
                   1075:             }
1.5       bowersj2 1076:         }
                   1077:     }
                   1078: </script>
                   1079: SCRIPT
1.25      bowersj2 1080:     }
                   1081: 
                   1082:     # Only print "select all" and "unselect all" if there are five or
                   1083:     # more choices; fewer then that and it looks silly.
                   1084:     if ($self->{'multichoice'} && scalar(@{$self->{CHOICES}}) > 4) {
1.5       bowersj2 1085:         $buttons = <<BUTTONS;
                   1086: <br />
1.18      bowersj2 1087: <input type="button" onclick="checkall(true, '$var')" value="Select All" />
                   1088: <input type="button" onclick="checkall(false, '$var')" value="Unselect All" />
1.6       bowersj2 1089: <br />&nbsp;
1.5       bowersj2 1090: BUTTONS
                   1091:     }
                   1092: 
1.16      bowersj2 1093:     if (defined $self->{ERROR_MSG}) {
1.6       bowersj2 1094:         $result .= '<br /><font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br />';
1.5       bowersj2 1095:     }
                   1096: 
                   1097:     $result .= $buttons;
1.6       bowersj2 1098:     
1.5       bowersj2 1099:     $result .= "<table>\n\n";
                   1100: 
1.25      bowersj2 1101:     my %checkedChoices;
                   1102:     my $checkedChoicesFunc;
                   1103: 
                   1104:     if (defined($self->{DEFAULT_VALUE})) {
                   1105:         $checkedChoicesFunc = eval ($self->{DEFAULT_VALUE});
                   1106:         die 'Error in default value code for variable ' . 
                   1107:             {'variable'} . ', Perl said:' . $@ if $@;
                   1108:     } else {
                   1109:         $checkedChoicesFunc = sub { return ''; };
                   1110:     }
                   1111: 
                   1112:     # Process which choices should be checked.
                   1113:     if ($self->{'multichoice'}) {
                   1114:         for my $selectedChoice (split(/\|\|\|/, (&$checkedChoicesFunc($helper, $self)))) {
                   1115:             $checkedChoices{$selectedChoice} = 1;
                   1116:         }
                   1117:     } else {
                   1118:         # single choice
                   1119:         my $selectedChoice = &$checkedChoicesFunc($helper, $self);
                   1120:         
                   1121:         my $foundChoice = 0;
                   1122:         
                   1123:         # check that the choice is in the list of choices.
                   1124:         for my $choice (@{$self->{CHOICES}}) {
                   1125:             if ($choice->[1] eq $selectedChoice) {
                   1126:                 $checkedChoices{$choice->[1]} = 1;
                   1127:                 $foundChoice = 1;
                   1128:             }
                   1129:         }
                   1130:         
                   1131:         # If we couldn't find the choice, pick the first one 
                   1132:         if (!$foundChoice) {
                   1133:             $checkedChoices{$self->{CHOICES}->[0]->[1]} = 1;
                   1134:         }
                   1135:     }
                   1136: 
1.5       bowersj2 1137:     my $type = "radio";
                   1138:     if ($self->{'multichoice'}) { $type = 'checkbox'; }
                   1139:     foreach my $choice (@{$self->{CHOICES}}) {
                   1140:         $result .= "<tr>\n<td width='20'>&nbsp;</td>\n";
                   1141:         $result .= "<td valign='top'><input type='$type' name='$var.forminput'"
                   1142:             . "' value='" . 
                   1143:             HTML::Entities::encode($choice->[1]) 
                   1144:             . "'";
1.25      bowersj2 1145:         if ($checkedChoices{$choice->[1]}) {
1.5       bowersj2 1146:             $result .= " checked ";
                   1147:         }
1.13      bowersj2 1148:         my $choiceLabel = $choice->[0];
                   1149:         if ($choice->[4]) {  # if we need to evaluate this choice
                   1150:             $choiceLabel = "sub { my $helper = shift; my $state = shift;" .
                   1151:                 $choiceLabel . "}";
                   1152:             $choiceLabel = eval($choiceLabel);
                   1153:             $choiceLabel = &$choiceLabel($helper, $self);
                   1154:         }
                   1155:         $result .= "/></td><td> " . $choiceLabel . "</td></tr>\n";
1.5       bowersj2 1156:     }
                   1157:     $result .= "</table>\n\n\n";
                   1158:     $result .= $buttons;
                   1159: 
                   1160:     return $result;
                   1161: }
                   1162: 
                   1163: # If a NEXTSTATE was given or a nextstate for this choice was
                   1164: # given, switch to it
                   1165: sub postprocess {
                   1166:     my $self = shift;
                   1167:     my $chosenValue = $ENV{'form.' . $self->{'variable'} . '.forminput'};
                   1168: 
1.26      bowersj2 1169:     if (!defined($chosenValue) && !$self->{'allowempty'}) {
1.6       bowersj2 1170:         $self->{ERROR_MSG} = "You must choose one or more choices to" .
                   1171:             " continue.";
                   1172:         return 0;
                   1173:     }
                   1174: 
1.28    ! bowersj2 1175:     if (ref($chosenValue)) {
        !          1176:         $helper->{VARS}->{$self->{'variable'}} = join('|||', @$chosenValue);
1.6       bowersj2 1177:     }
                   1178: 
1.5       bowersj2 1179:     if (defined($self->{NEXTSTATE})) {
                   1180:         $helper->changeState($self->{NEXTSTATE});
                   1181:     }
                   1182:     
                   1183:     foreach my $choice (@{$self->{CHOICES}}) {
                   1184:         if ($choice->[1] eq $chosenValue) {
                   1185:             if (defined($choice->[2])) {
                   1186:                 $helper->changeState($choice->[2]);
                   1187:             }
                   1188:         }
                   1189:     }
1.6       bowersj2 1190:     return 1;
1.5       bowersj2 1191: }
                   1192: 1;
                   1193: 
                   1194: package Apache::lonhelper::date;
                   1195: 
                   1196: =pod
                   1197: 
                   1198: =head2 Element: date
                   1199: 
                   1200: Date elements allow the selection of a date with a drop down list.
                   1201: 
                   1202: Date elements can take two attributes:
                   1203: 
                   1204: =over 4
                   1205: 
                   1206: =item * B<variable>: The name of the variable to store the chosen
                   1207:         date in. Required.
                   1208: 
                   1209: =item * B<hoursminutes>: If a true value, the date will show hours
                   1210:         and minutes, as well as month/day/year. If false or missing,
                   1211:         the date will only show the month, day, and year.
                   1212: 
                   1213: =back
                   1214: 
                   1215: Date elements contain only an option <nextstate> tag to determine
                   1216: the next state.
                   1217: 
                   1218: Example:
                   1219: 
                   1220:  <date variable="DUE_DATE" hoursminutes="1">
                   1221:    <nextstate>choose_why</nextstate>
                   1222:    </date>
                   1223: 
                   1224: =cut
                   1225: 
                   1226: no strict;
                   1227: @ISA = ("Apache::lonhelper::element");
                   1228: use strict;
                   1229: 
                   1230: use Time::localtime;
                   1231: 
                   1232: BEGIN {
1.7       bowersj2 1233:     &Apache::lonhelper::register('Apache::lonhelper::date',
1.5       bowersj2 1234:                               ('date'));
                   1235: }
                   1236: 
                   1237: # Don't need to override the "new" from element
                   1238: sub new {
                   1239:     my $ref = Apache::lonhelper::element->new();
                   1240:     bless($ref);
                   1241: }
                   1242: 
                   1243: my @months = ("January", "February", "March", "April", "May", "June", "July",
                   1244: 	      "August", "September", "October", "November", "December");
                   1245: 
                   1246: # CONSTRUCTION: Construct the message element from the XML
                   1247: sub start_date {
                   1248:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1249: 
                   1250:     if ($target ne 'helper') {
                   1251:         return '';
                   1252:     }
                   1253: 
                   1254:     $paramHash->{'variable'} = $token->[2]{'variable'};
                   1255:     $helper->declareVar($paramHash->{'variable'});
                   1256:     $paramHash->{'hoursminutes'} = $token->[2]{'hoursminutes'};
                   1257: }
                   1258: 
                   1259: sub end_date {
                   1260:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1261: 
                   1262:     if ($target ne 'helper') {
                   1263:         return '';
                   1264:     }
                   1265:     Apache::lonhelper::date->new();
                   1266:     return '';
                   1267: }
                   1268: 
                   1269: sub render {
                   1270:     my $self = shift;
                   1271:     my $result = "";
                   1272:     my $var = $self->{'variable'};
                   1273: 
                   1274:     my $date;
                   1275:     
                   1276:     # Default date: The current hour.
                   1277:     $date = localtime();
                   1278:     $date->min(0);
                   1279: 
                   1280:     if (defined $self->{ERROR_MSG}) {
                   1281:         $result .= '<font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
                   1282:     }
                   1283: 
                   1284:     # Month
                   1285:     my $i;
                   1286:     $result .= "<select name='${var}month'>\n";
                   1287:     for ($i = 0; $i < 12; $i++) {
                   1288:         if ($i == $date->mon) {
                   1289:             $result .= "<option value='$i' selected>";
                   1290:         } else {
                   1291:             $result .= "<option value='$i'>";
                   1292:         }
                   1293:         $result .= $months[$i] . "</option>\n";
                   1294:     }
                   1295:     $result .= "</select>\n";
                   1296: 
                   1297:     # Day
                   1298:     $result .= "<select name='${var}day'>\n";
                   1299:     for ($i = 1; $i < 32; $i++) {
                   1300:         if ($i == $date->mday) {
                   1301:             $result .= '<option selected>';
                   1302:         } else {
                   1303:             $result .= '<option>';
                   1304:         }
                   1305:         $result .= "$i</option>\n";
                   1306:     }
                   1307:     $result .= "</select>,\n";
                   1308: 
                   1309:     # Year
                   1310:     $result .= "<select name='${var}year'>\n";
                   1311:     for ($i = 2000; $i < 2030; $i++) { # update this after 64-bit dates
                   1312:         if ($date->year + 1900 == $i) {
                   1313:             $result .= "<option selected>";
                   1314:         } else {
                   1315:             $result .= "<option>";
                   1316:         }
                   1317:         $result .= "$i</option>\n";
                   1318:     }
                   1319:     $result .= "</select>,\n";
                   1320: 
                   1321:     # Display Hours and Minutes if they are called for
                   1322:     if ($self->{'hoursminutes'}) {
                   1323:         # Build hour
                   1324:         $result .= "<select name='${var}hour'>\n";
                   1325:         $result .= "<option " . ($date->hour == 0 ? 'selected ':'') .
                   1326:             " value='0'>midnight</option>\n";
                   1327:         for ($i = 1; $i < 12; $i++) {
                   1328:             if ($date->hour == $i) {
                   1329:                 $result .= "<option selected value='$i'>$i a.m.</option>\n";
                   1330:             } else {
                   1331:                 $result .= "<option value='$i'>$i a.m</option>\n";
                   1332:             }
                   1333:         }
                   1334:         $result .= "<option " . ($date->hour == 12 ? 'selected ':'') .
                   1335:             " value='12'>noon</option>\n";
                   1336:         for ($i = 13; $i < 24; $i++) {
                   1337:             my $printedHour = $i - 12;
                   1338:             if ($date->hour == $i) {
                   1339:                 $result .= "<option selected value='$i'>$printedHour p.m.</option>\n";
                   1340:             } else {
                   1341:                 $result .= "<option value='$i'>$printedHour p.m.</option>\n";
                   1342:             }
                   1343:         }
                   1344: 
                   1345:         $result .= "</select> :\n";
                   1346: 
                   1347:         $result .= "<select name='${var}minute'>\n";
                   1348:         for ($i = 0; $i < 60; $i++) {
                   1349:             my $printedMinute = $i;
                   1350:             if ($i < 10) {
                   1351:                 $printedMinute = "0" . $printedMinute;
                   1352:             }
                   1353:             if ($date->min == $i) {
                   1354:                 $result .= "<option selected>";
                   1355:             } else {
                   1356:                 $result .= "<option>";
                   1357:             }
                   1358:             $result .= "$printedMinute</option>\n";
                   1359:         }
                   1360:         $result .= "</select>\n";
                   1361:     }
                   1362: 
                   1363:     return $result;
                   1364: 
                   1365: }
                   1366: # If a NEXTSTATE was given, switch to it
                   1367: sub postprocess {
                   1368:     my $self = shift;
                   1369:     my $var = $self->{'variable'};
                   1370:     my $month = $ENV{'form.' . $var . 'month'}; 
                   1371:     my $day = $ENV{'form.' . $var . 'day'}; 
                   1372:     my $year = $ENV{'form.' . $var . 'year'}; 
                   1373:     my $min = 0; 
                   1374:     my $hour = 0;
                   1375:     if ($self->{'hoursminutes'}) {
                   1376:         $min = $ENV{'form.' . $var . 'minute'};
                   1377:         $hour = $ENV{'form.' . $var . 'hour'};
                   1378:     }
                   1379: 
                   1380:     my $chosenDate = Time::Local::timelocal(0, $min, $hour, $day, $month, $year);
                   1381:     # Check to make sure that the date was not automatically co-erced into a 
                   1382:     # valid date, as we want to flag that as an error
                   1383:     # This happens for "Feb. 31", for instance, which is coerced to March 2 or
                   1384:     # 3, depending on if it's a leapyear
                   1385:     my $checkDate = localtime($chosenDate);
                   1386: 
                   1387:     if ($checkDate->mon != $month || $checkDate->mday != $day ||
                   1388:         $checkDate->year + 1900 != $year) {
                   1389:         $self->{ERROR_MSG} = "Can't use " . $months[$month] . " $day, $year as a "
                   1390:             . "date because it doesn't exist. Please enter a valid date.";
1.6       bowersj2 1391:         return 0;
1.5       bowersj2 1392:     }
                   1393: 
                   1394:     $helper->{VARS}->{$var} = $chosenDate;
                   1395: 
                   1396:     if (defined($self->{NEXTSTATE})) {
                   1397:         $helper->changeState($self->{NEXTSTATE});
                   1398:     }
1.6       bowersj2 1399: 
                   1400:     return 1;
1.5       bowersj2 1401: }
                   1402: 1;
                   1403: 
                   1404: package Apache::lonhelper::resource;
                   1405: 
                   1406: =pod
                   1407: 
                   1408: =head2 Element: resource
                   1409: 
                   1410: <resource> elements allow the user to select one or multiple resources
                   1411: from the current course. You can filter out which resources they can view,
                   1412: and filter out which resources they can select. The course will always
                   1413: be displayed fully expanded, because of the difficulty of maintaining
                   1414: selections across folder openings and closings. If this is fixed, then
                   1415: the user can manipulate the folders.
                   1416: 
                   1417: <resource> takes the standard variable attribute to control what helper
                   1418: variable stores the results. It also takes a "multichoice" attribute,
1.17      bowersj2 1419: which controls whether the user can select more then one resource. The 
                   1420: "toponly" attribute controls whether the resource display shows just the
                   1421: resources in that sequence, or recurses into all sub-sequences, defaulting
                   1422: to false.
1.5       bowersj2 1423: 
                   1424: B<SUB-TAGS>
                   1425: 
                   1426: =over 4
                   1427: 
                   1428: =item * <filterfunc>: If you want to filter what resources are displayed
                   1429:   to the user, use a filter func. The <filterfunc> tag should contain
                   1430:   Perl code that when wrapped with "sub { my $res = shift; " and "}" is 
                   1431:   a function that returns true if the resource should be displayed, 
                   1432:   and false if it should be skipped. $res is a resource object. 
                   1433:   (See Apache::lonnavmaps documentation for information about the 
                   1434:   resource object.)
                   1435: 
                   1436: =item * <choicefunc>: Same as <filterfunc>, except that controls whether
                   1437:   the given resource can be chosen. (It is almost always a good idea to
                   1438:   show the user the folders, for instance, but you do not always want to 
                   1439:   let the user select them.)
                   1440: 
                   1441: =item * <nextstate>: Standard nextstate behavior.
                   1442: 
                   1443: =item * <valuefunc>: This function controls what is returned by the resource
                   1444:   when the user selects it. Like filterfunc and choicefunc, it should be
                   1445:   a function fragment that when wrapped by "sub { my $res = shift; " and
                   1446:   "}" returns a string representing what you want to have as the value. By
                   1447:   default, the value will be the resource ID of the object ($res->{ID}).
                   1448: 
1.13      bowersj2 1449: =item * <mapurl>: If the URL of a map is given here, only that map
                   1450:   will be displayed, instead of the whole course.
                   1451: 
1.5       bowersj2 1452: =back
                   1453: 
                   1454: =cut
                   1455: 
                   1456: no strict;
                   1457: @ISA = ("Apache::lonhelper::element");
                   1458: use strict;
                   1459: 
                   1460: BEGIN {
1.7       bowersj2 1461:     &Apache::lonhelper::register('Apache::lonhelper::resource',
1.5       bowersj2 1462:                               ('resource', 'filterfunc', 
1.13      bowersj2 1463:                                'choicefunc', 'valuefunc',
                   1464:                                'mapurl'));
1.5       bowersj2 1465: }
                   1466: 
                   1467: sub new {
                   1468:     my $ref = Apache::lonhelper::element->new();
                   1469:     bless($ref);
                   1470: }
                   1471: 
                   1472: # CONSTRUCTION: Construct the message element from the XML
                   1473: sub start_resource {
                   1474:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1475: 
                   1476:     if ($target ne 'helper') {
                   1477:         return '';
                   1478:     }
                   1479: 
                   1480:     $paramHash->{'variable'} = $token->[2]{'variable'};
                   1481:     $helper->declareVar($paramHash->{'variable'});
1.14      bowersj2 1482:     $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
1.17      bowersj2 1483:     $paramHash->{'toponly'} = $token->[2]{'toponly'};
1.5       bowersj2 1484:     return '';
                   1485: }
                   1486: 
                   1487: sub end_resource {
                   1488:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1489: 
                   1490:     if ($target ne 'helper') {
                   1491:         return '';
                   1492:     }
                   1493:     if (!defined($paramHash->{FILTER_FUNC})) {
                   1494:         $paramHash->{FILTER_FUNC} = sub {return 1;};
                   1495:     }
                   1496:     if (!defined($paramHash->{CHOICE_FUNC})) {
                   1497:         $paramHash->{CHOICE_FUNC} = sub {return 1;};
                   1498:     }
                   1499:     if (!defined($paramHash->{VALUE_FUNC})) {
                   1500:         $paramHash->{VALUE_FUNC} = sub {my $res = shift; return $res->{ID}; };
                   1501:     }
                   1502:     Apache::lonhelper::resource->new();
1.4       bowersj2 1503:     return '';
                   1504: }
                   1505: 
1.5       bowersj2 1506: sub start_filterfunc {
                   1507:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1508: 
                   1509:     if ($target ne 'helper') {
                   1510:         return '';
                   1511:     }
                   1512: 
                   1513:     my $contents = Apache::lonxml::get_all_text('/filterfunc',
                   1514:                                                 $parser);
                   1515:     $contents = 'sub { my $res = shift; ' . $contents . '}';
                   1516:     $paramHash->{FILTER_FUNC} = eval $contents;
                   1517: }
                   1518: 
                   1519: sub end_filterfunc { return ''; }
                   1520: 
                   1521: sub start_choicefunc {
                   1522:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1523: 
                   1524:     if ($target ne 'helper') {
                   1525:         return '';
                   1526:     }
                   1527: 
                   1528:     my $contents = Apache::lonxml::get_all_text('/choicefunc',
                   1529:                                                 $parser);
                   1530:     $contents = 'sub { my $res = shift; ' . $contents . '}';
                   1531:     $paramHash->{CHOICE_FUNC} = eval $contents;
                   1532: }
                   1533: 
                   1534: sub end_choicefunc { return ''; }
                   1535: 
                   1536: sub start_valuefunc {
                   1537:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1538: 
                   1539:     if ($target ne 'helper') {
                   1540:         return '';
                   1541:     }
                   1542: 
                   1543:     my $contents = Apache::lonxml::get_all_text('/valuefunc',
                   1544:                                                 $parser);
                   1545:     $contents = 'sub { my $res = shift; ' . $contents . '}';
                   1546:     $paramHash->{VALUE_FUNC} = eval $contents;
                   1547: }
                   1548: 
                   1549: sub end_valuefunc { return ''; }
                   1550: 
1.13      bowersj2 1551: sub start_mapurl {
                   1552:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1553: 
                   1554:     if ($target ne 'helper') {
                   1555:         return '';
                   1556:     }
                   1557: 
                   1558:     my $contents = Apache::lonxml::get_all_text('/mapurl',
                   1559:                                                 $parser);
1.14      bowersj2 1560:     $paramHash->{MAP_URL} = $contents;
1.13      bowersj2 1561: }
                   1562: 
                   1563: sub end_mapurl { return ''; }
                   1564: 
1.5       bowersj2 1565: # A note, in case I don't get to this before I leave.
                   1566: # If someone complains about the "Back" button returning them
                   1567: # to the previous folder state, instead of returning them to
                   1568: # the previous helper state, the *correct* answer is for the helper
                   1569: # to keep track of how many times the user has manipulated the folders,
                   1570: # and feed that to the history.go() call in the helper rendering routines.
                   1571: # If done correctly, the helper itself can keep track of how many times
                   1572: # it renders the same states, so it doesn't go in just this state, and
                   1573: # you can lean on the browser back button to make sure it all chains
                   1574: # correctly.
                   1575: # Right now, though, I'm just forcing all folders open.
                   1576: 
                   1577: sub render {
                   1578:     my $self = shift;
                   1579:     my $result = "";
                   1580:     my $var = $self->{'variable'};
                   1581:     my $curVal = $helper->{VARS}->{$var};
                   1582: 
1.15      bowersj2 1583:     my $buttons = '';
                   1584: 
                   1585:     if ($self->{'multichoice'}) {
                   1586:         $result = <<SCRIPT;
                   1587: <script>
1.18      bowersj2 1588:     function checkall(value, checkName) {
1.15      bowersj2 1589: 	for (i=0; i<document.forms.helpform.elements.length; i++) {
                   1590:             ele = document.forms.helpform.elements[i];
1.18      bowersj2 1591:             if (ele.name == checkName + '.forminput') {
1.15      bowersj2 1592:                 document.forms.helpform.elements[i].checked=value;
                   1593:             }
                   1594:         }
                   1595:     }
                   1596: </script>
                   1597: SCRIPT
                   1598:         $buttons = <<BUTTONS;
                   1599: <br /> &nbsp;
1.18      bowersj2 1600: <input type="button" onclick="checkall(true, '$var')" value="Select All Resources" />
                   1601: <input type="button" onclick="checkall(false, '$var')" value="Unselect All Resources" />
1.15      bowersj2 1602: <br /> &nbsp;
                   1603: BUTTONS
                   1604:     }
                   1605: 
1.5       bowersj2 1606:     if (defined $self->{ERROR_MSG}) {
1.14      bowersj2 1607:         $result .= '<br /><font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
1.5       bowersj2 1608:     }
                   1609: 
1.15      bowersj2 1610:     $result .= $buttons;
                   1611: 
1.5       bowersj2 1612:     my $filterFunc = $self->{FILTER_FUNC};
                   1613:     my $choiceFunc = $self->{CHOICE_FUNC};
                   1614:     my $valueFunc = $self->{VALUE_FUNC};
1.13      bowersj2 1615:     my $mapUrl = $self->{MAP_URL};
1.14      bowersj2 1616:     my $multichoice = $self->{'multichoice'};
1.5       bowersj2 1617: 
                   1618:     # Create the composite function that renders the column on the nav map
                   1619:     # have to admit any language that lets me do this can't be all bad
                   1620:     #  - Jeremy (Pythonista) ;-)
                   1621:     my $checked = 0;
                   1622:     my $renderColFunc = sub {
                   1623:         my ($resource, $part, $params) = @_;
1.14      bowersj2 1624: 
                   1625:         my $inputType;
                   1626:         if ($multichoice) { $inputType = 'checkbox'; }
                   1627:         else {$inputType = 'radio'; }
                   1628: 
1.5       bowersj2 1629:         if (!&$choiceFunc($resource)) {
                   1630:             return '<td>&nbsp;</td>';
                   1631:         } else {
1.14      bowersj2 1632:             my $col = "<td><input type='$inputType' name='${var}.forminput' ";
                   1633:             if (!$checked && !$multichoice) {
1.5       bowersj2 1634:                 $col .= "checked ";
                   1635:                 $checked = 1;
                   1636:             }
                   1637:             $col .= "value='" . 
                   1638:                 HTML::Entities::encode(&$valueFunc($resource)) 
                   1639:                 . "' /></td>";
                   1640:             return $col;
                   1641:         }
                   1642:     };
                   1643: 
1.17      bowersj2 1644:     $ENV{'form.condition'} = !$self->{'toponly'};
1.5       bowersj2 1645:     $result .= 
                   1646:         &Apache::lonnavmaps::render( { 'cols' => [$renderColFunc, 
                   1647:                                                   Apache::lonnavmaps::resource()],
                   1648:                                        'showParts' => 0,
                   1649:                                        'filterFunc' => $filterFunc,
1.13      bowersj2 1650:                                        'resource_no_folder_link' => 1,
                   1651:                                        'iterator_map' => $mapUrl }
1.5       bowersj2 1652:                                        );
1.15      bowersj2 1653: 
                   1654:     $result .= $buttons;
1.5       bowersj2 1655:                                                 
                   1656:     return $result;
                   1657: }
                   1658:     
                   1659: sub postprocess {
                   1660:     my $self = shift;
1.14      bowersj2 1661: 
                   1662:     if ($self->{'multichoice'} && !$helper->{VARS}->{$self->{'variable'}}) {
                   1663:         $self->{ERROR_MSG} = 'You must choose at least one resource to continue.';
                   1664:         return 0;
                   1665:     }
                   1666: 
1.5       bowersj2 1667:     if (defined($self->{NEXTSTATE})) {
                   1668:         $helper->changeState($self->{NEXTSTATE});
                   1669:     }
1.6       bowersj2 1670: 
                   1671:     return 1;
1.5       bowersj2 1672: }
                   1673: 
                   1674: 1;
                   1675: 
                   1676: package Apache::lonhelper::student;
                   1677: 
                   1678: =pod
                   1679: 
                   1680: =head2 Element: student
                   1681: 
                   1682: Student elements display a choice of students enrolled in the current
                   1683: course. Currently it is primitive; this is expected to evolve later.
                   1684: 
                   1685: Student elements take two attributes: "variable", which means what
                   1686: it usually does, and "multichoice", which if true allows the user
                   1687: to select multiple students.
                   1688: 
                   1689: =cut
                   1690: 
                   1691: no strict;
                   1692: @ISA = ("Apache::lonhelper::element");
                   1693: use strict;
                   1694: 
                   1695: 
                   1696: 
                   1697: BEGIN {
1.7       bowersj2 1698:     &Apache::lonhelper::register('Apache::lonhelper::student',
1.5       bowersj2 1699:                               ('student'));
                   1700: }
                   1701: 
                   1702: sub new {
                   1703:     my $ref = Apache::lonhelper::element->new();
                   1704:     bless($ref);
                   1705: }
1.4       bowersj2 1706: 
1.5       bowersj2 1707: sub start_student {
1.4       bowersj2 1708:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1709: 
                   1710:     if ($target ne 'helper') {
                   1711:         return '';
                   1712:     }
                   1713: 
1.5       bowersj2 1714:     $paramHash->{'variable'} = $token->[2]{'variable'};
                   1715:     $helper->declareVar($paramHash->{'variable'});
                   1716:     $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
1.12      bowersj2 1717:     if (defined($token->[2]{'nextstate'})) {
                   1718:         $paramHash->{NEXTSTATE} = $token->[2]{'nextstate'};
                   1719:     }
                   1720:     
1.5       bowersj2 1721: }    
                   1722: 
                   1723: sub end_student {
                   1724:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1725: 
                   1726:     if ($target ne 'helper') {
                   1727:         return '';
                   1728:     }
                   1729:     Apache::lonhelper::student->new();
1.3       bowersj2 1730: }
1.5       bowersj2 1731: 
                   1732: sub render {
                   1733:     my $self = shift;
                   1734:     my $result = '';
                   1735:     my $buttons = '';
1.18      bowersj2 1736:     my $var = $self->{'variable'};
1.5       bowersj2 1737: 
                   1738:     if ($self->{'multichoice'}) {
                   1739:         $result = <<SCRIPT;
                   1740: <script>
1.18      bowersj2 1741:     function checkall(value, checkName) {
1.15      bowersj2 1742: 	for (i=0; i<document.forms.helpform.elements.length; i++) {
1.18      bowersj2 1743:             ele = document.forms.helpform.elements[i];
                   1744:             if (ele.name == checkName + '.forminput') {
                   1745:                 document.forms.helpform.elements[i].checked=value;
                   1746:             }
1.5       bowersj2 1747:         }
                   1748:     }
                   1749: </script>
                   1750: SCRIPT
                   1751:         $buttons = <<BUTTONS;
                   1752: <br />
1.18      bowersj2 1753: <input type="button" onclick="checkall(true, '$var')" value="Select All Students" />
                   1754: <input type="button" onclick="checkall(false, '$var')" value="Unselect All Students" />
1.5       bowersj2 1755: <br />
                   1756: BUTTONS
                   1757:     }
                   1758: 
                   1759:     if (defined $self->{ERROR_MSG}) {
                   1760:         $result .= '<font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
                   1761:     }
                   1762: 
                   1763:     # Load up the students
                   1764:     my $choices = &Apache::loncoursedata::get_classlist();
                   1765:     my @keys = keys %{$choices};
                   1766: 
                   1767:     # Constants
                   1768:     my $section = Apache::loncoursedata::CL_SECTION();
                   1769:     my $fullname = Apache::loncoursedata::CL_FULLNAME();
                   1770: 
                   1771:     # Sort by: Section, name
                   1772:     @keys = sort {
                   1773:         if ($choices->{$a}->[$section] ne $choices->{$b}->[$section]) {
                   1774:             return $choices->{$a}->[$section] cmp $choices->{$b}->[$section];
                   1775:         }
                   1776:         return $choices->{$a}->[$fullname] cmp $choices->{$b}->[$fullname];
                   1777:     } @keys;
                   1778: 
                   1779:     my $type = 'radio';
                   1780:     if ($self->{'multichoice'}) { $type = 'checkbox'; }
                   1781:     $result .= "<table cellspacing='2' cellpadding='2' border='0'>\n";
                   1782:     $result .= "<tr><td></td><td align='center'><b>Student Name</b></td>".
                   1783:         "<td align='center'><b>Section</b></td></tr>";
                   1784: 
                   1785:     my $checked = 0;
                   1786:     foreach (@keys) {
                   1787:         $result .= "<tr><td><input type='$type' name='" .
                   1788:             $self->{'variable'} . '.forminput' . "'";
                   1789:             
                   1790:         if (!$self->{'multichoice'} && !$checked) {
                   1791:             $result .= " checked ";
                   1792:             $checked = 1;
                   1793:         }
                   1794:         $result .=
1.19      bowersj2 1795:             " value='" . HTML::Entities::encode($_ . ':' . $choices->{$_}->[$section])
1.5       bowersj2 1796:             . "' /></td><td>"
                   1797:             . HTML::Entities::encode($choices->{$_}->[$fullname])
                   1798:             . "</td><td align='center'>" 
                   1799:             . HTML::Entities::encode($choices->{$_}->[$section])
                   1800:             . "</td></tr>\n";
                   1801:     }
                   1802: 
                   1803:     $result .= "</table>\n\n";
                   1804:     $result .= $buttons;    
1.4       bowersj2 1805:     
1.5       bowersj2 1806:     return $result;
                   1807: }
                   1808: 
1.6       bowersj2 1809: sub postprocess {
                   1810:     my $self = shift;
                   1811: 
                   1812:     my $result = $ENV{'form.' . $self->{'variable'} . '.forminput'};
                   1813:     if (!$result) {
                   1814:         $self->{ERROR_MSG} = 'You must choose at least one student '.
                   1815:             'to continue.';
                   1816:         return 0;
                   1817:     }
                   1818: 
                   1819:     if (defined($self->{NEXTSTATE})) {
                   1820:         $helper->changeState($self->{NEXTSTATE});
                   1821:     }
                   1822: 
                   1823:     return 1;
                   1824: }
                   1825: 
1.5       bowersj2 1826: 1;
                   1827: 
                   1828: package Apache::lonhelper::files;
                   1829: 
                   1830: =pod
                   1831: 
                   1832: =head2 Element: files
                   1833: 
                   1834: files allows the users to choose files from a given directory on the
                   1835: server. It is always multichoice and stores the result as a triple-pipe
                   1836: delimited entry in the helper variables. 
                   1837: 
                   1838: Since it is extremely unlikely that you can actually code a constant
                   1839: representing the directory you wish to allow the user to search, <files>
                   1840: takes a subroutine that returns the name of the directory you wish to
                   1841: have the user browse.
                   1842: 
                   1843: files accepts the attribute "variable" to control where the files chosen
                   1844: are put. It accepts the attribute "multichoice" as the other attribute,
                   1845: defaulting to false, which if true will allow the user to select more
                   1846: then one choice. 
                   1847: 
                   1848: <files> accepts three subtags. One is the "nextstate" sub-tag that works
                   1849: as it does with the other tags. Another is a <filechoice> sub tag that
                   1850: is Perl code that, when surrounded by "sub {" and "}" will return a
                   1851: string representing what directory on the server to allow the user to 
                   1852: choose files from. Finally, the <filefilter> subtag should contain Perl
                   1853: code that when surrounded by "sub { my $filename = shift; " and "}",
                   1854: returns a true value if the user can pick that file, or false otherwise.
                   1855: The filename passed to the function will be just the name of the file, 
                   1856: with no path info.
                   1857: 
                   1858: =cut
                   1859: 
                   1860: no strict;
                   1861: @ISA = ("Apache::lonhelper::element");
                   1862: use strict;
                   1863: 
                   1864: BEGIN {
1.7       bowersj2 1865:     &Apache::lonhelper::register('Apache::lonhelper::files',
                   1866:                                  ('files', 'filechoice', 'filefilter'));
1.5       bowersj2 1867: }
                   1868: 
                   1869: sub new {
                   1870:     my $ref = Apache::lonhelper::element->new();
                   1871:     bless($ref);
                   1872: }
                   1873: 
                   1874: sub start_files {
                   1875:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1876: 
                   1877:     if ($target ne 'helper') {
                   1878:         return '';
                   1879:     }
                   1880:     $paramHash->{'variable'} = $token->[2]{'variable'};
                   1881:     $helper->declareVar($paramHash->{'variable'});
                   1882:     $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
                   1883: }    
                   1884: 
                   1885: sub end_files {
                   1886:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1887: 
                   1888:     if ($target ne 'helper') {
                   1889:         return '';
                   1890:     }
                   1891:     if (!defined($paramHash->{FILTER_FUNC})) {
                   1892:         $paramHash->{FILTER_FUNC} = sub { return 1; };
                   1893:     }
                   1894:     Apache::lonhelper::files->new();
                   1895: }    
                   1896: 
                   1897: sub start_filechoice {
                   1898:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1899: 
                   1900:     if ($target ne 'helper') {
                   1901:         return '';
                   1902:     }
                   1903:     $paramHash->{'filechoice'} = Apache::lonxml::get_all_text('/filechoice',
                   1904:                                                               $parser);
                   1905: }
                   1906: 
                   1907: sub end_filechoice { return ''; }
                   1908: 
                   1909: sub start_filefilter {
                   1910:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   1911: 
                   1912:     if ($target ne 'helper') {
                   1913:         return '';
                   1914:     }
                   1915: 
                   1916:     my $contents = Apache::lonxml::get_all_text('/filefilter',
                   1917:                                                 $parser);
                   1918:     $contents = 'sub { my $filename = shift; ' . $contents . '}';
                   1919:     $paramHash->{FILTER_FUNC} = eval $contents;
                   1920: }
                   1921: 
                   1922: sub end_filefilter { return ''; }
1.3       bowersj2 1923: 
                   1924: sub render {
                   1925:     my $self = shift;
1.5       bowersj2 1926:     my $result = '';
                   1927:     my $var = $self->{'variable'};
                   1928:     
                   1929:     my $subdirFunc = eval('sub {' . $self->{'filechoice'} . '}');
1.11      bowersj2 1930:     die 'Error in resource filter code for variable ' . 
                   1931:         {'variable'} . ', Perl said:' . $@ if $@;
                   1932: 
1.5       bowersj2 1933:     my $subdir = &$subdirFunc();
                   1934: 
                   1935:     my $filterFunc = $self->{FILTER_FUNC};
                   1936:     my $buttons = '';
1.22      bowersj2 1937:     my $type = 'radio';
                   1938:     if ($self->{'multichoice'}) {
                   1939:         $type = 'checkbox';
                   1940:     }
1.5       bowersj2 1941: 
                   1942:     if ($self->{'multichoice'}) {
                   1943:         $result = <<SCRIPT;
                   1944: <script>
1.18      bowersj2 1945:     function checkall(value, checkName) {
1.15      bowersj2 1946: 	for (i=0; i<document.forms.helpform.elements.length; i++) {
                   1947:             ele = document.forms.helpform.elements[i];
1.18      bowersj2 1948:             if (ele.name == checkName + '.forminput') {
1.15      bowersj2 1949:                 document.forms.helpform.elements[i].checked=value;
1.5       bowersj2 1950:             }
                   1951:         }
                   1952:     }
1.21      bowersj2 1953: 
1.22      bowersj2 1954:     function checkallclass(value, className) {
1.21      bowersj2 1955:         for (i=0; i<document.forms.helpform.elements.length; i++) {
                   1956:             ele = document.forms.helpform.elements[i];
1.22      bowersj2 1957:             if (ele.type == "$type" && ele.onclick) {
1.21      bowersj2 1958:                 document.forms.helpform.elements[i].checked=value;
                   1959:             }
                   1960:         }
                   1961:     }
1.5       bowersj2 1962: </script>
                   1963: SCRIPT
1.15      bowersj2 1964:         $buttons = <<BUTTONS;
1.5       bowersj2 1965: <br /> &nbsp;
1.18      bowersj2 1966: <input type="button" onclick="checkall(true, '$var')" value="Select All Files" />
                   1967: <input type="button" onclick="checkall(false, '$var')" value="Unselect All Files" />
1.23      bowersj2 1968: BUTTONS
                   1969: 
                   1970:         if ($helper->{VARS}->{'construction'}) {
                   1971:             $buttons .= <<BUTTONS;
1.22      bowersj2 1972: <input type="button" onclick="checkallclass(true, 'Published')" value="Select All Published" />
                   1973: <input type="button" onclick="checkallclass(false, 'Published')" value="Unselect All Published" />
1.5       bowersj2 1974: <br /> &nbsp;
                   1975: BUTTONS
1.23      bowersj2 1976:        }
1.5       bowersj2 1977:     }
                   1978: 
                   1979:     # Get the list of files in this directory.
                   1980:     my @fileList;
                   1981: 
                   1982:     # If the subdirectory is in local CSTR space
                   1983:     if ($subdir =~ m|/home/([^/]+)/public_html|) {
                   1984:         my $user = $1;
                   1985:         my $domain = $Apache::lonnet::perlvar{'lonDefDomain'};
                   1986:         @fileList = &Apache::lonnet::dirlist($subdir, $domain, $user, '');
                   1987:     } else {
                   1988:         # local library server resource space
                   1989:         @fileList = &Apache::lonnet::dirlist($subdir, $ENV{'user.domain'}, $ENV{'user.name'}, '');
                   1990:     }
1.3       bowersj2 1991: 
1.5       bowersj2 1992:     $result .= $buttons;
                   1993: 
1.6       bowersj2 1994:     if (defined $self->{ERROR_MSG}) {
                   1995:         $result .= '<br /><font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
                   1996:     }
                   1997: 
1.20      bowersj2 1998:     $result .= '<table border="0" cellpadding="2" cellspacing="0">';
1.5       bowersj2 1999: 
                   2000:     # Keeps track if there are no choices, prints appropriate error
                   2001:     # if there are none. 
                   2002:     my $choices = 0;
                   2003:     # Print each legitimate file choice.
                   2004:     for my $file (@fileList) {
                   2005:         $file = (split(/&/, $file))[0];
                   2006:         if ($file eq '.' || $file eq '..') {
                   2007:             next;
                   2008:         }
                   2009:         my $fileName = $subdir .'/'. $file;
                   2010:         if (&$filterFunc($file)) {
1.24      sakharuk 2011: 	    my $status;
                   2012: 	    my $color;
                   2013: 	    if ($helper->{VARS}->{'construction'}) {
                   2014: 		($status, $color) = @{fileState($subdir, $file)};
                   2015: 	    } else {
                   2016: 		$status = '';
                   2017: 		$color = '';
                   2018: 	    }
1.22      bowersj2 2019: 
                   2020:             # Netscape 4 is stupid and there's nowhere to put the
                   2021:             # information on the input tag that the file is Published,
                   2022:             # Unpublished, etc. In *real* browsers we can just say
                   2023:             # "class='Published'" and check the className attribute of
                   2024:             # the input tag, but Netscape 4 is too stupid to understand
                   2025:             # that attribute, and un-comprehended attributes are not
                   2026:             # reflected into the object model. So instead, what I do 
                   2027:             # is either have or don't have an "onclick" handler that 
                   2028:             # does nothing, give Published files the onclick handler, and
                   2029:             # have the checker scripts check for that. Stupid and clumsy,
                   2030:             # and only gives us binary "yes/no" information (at least I
                   2031:             # couldn't figure out how to reach into the event handler's
                   2032:             # actual code to retreive a value), but it works well enough
                   2033:             # here.
1.23      bowersj2 2034:         
1.22      bowersj2 2035:             my $onclick = '';
1.23      bowersj2 2036:             if ($status eq 'Published' && $helper->{VARS}->{'construction'}) {
1.22      bowersj2 2037:                 $onclick = 'onclick="a=1" ';
                   2038:             }
1.20      bowersj2 2039:             $result .= '<tr><td align="right"' . " bgcolor='$color'>" .
1.22      bowersj2 2040:                 "<input $onclick type='$type' name='" . $var
1.5       bowersj2 2041:             . ".forminput' value='" . HTML::Entities::encode($fileName) .
                   2042:                 "'";
                   2043:             if (!$self->{'multichoice'} && $choices == 0) {
                   2044:                 $result .= ' checked';
                   2045:             }
1.20      bowersj2 2046:             $result .= "/></td><td bgcolor='$color'>" . $file .
                   2047:                  "</td><td bgcolor='$color'>$status</td></tr>\n";
1.5       bowersj2 2048:             $choices++;
                   2049:         }
                   2050:     }
                   2051: 
                   2052:     $result .= "</table>\n";
                   2053: 
                   2054:     if (!$choices) {
                   2055:         $result .= '<font color="#FF0000">There are no files available to select in this directory. Please go back and select another option.</font><br /><br />';
                   2056:     }
                   2057: 
                   2058:     $result .= $buttons;
                   2059: 
                   2060:     return $result;
1.20      bowersj2 2061: }
                   2062: 
                   2063: # Determine the state of the file: Published, unpublished, modified.
                   2064: # Return the color it should be in and a label as a two-element array
                   2065: # reference.
                   2066: # Logic lifted from lonpubdir.pm, even though I don't know that it's still
                   2067: # the most right thing to do.
                   2068: 
                   2069: sub fileState {
                   2070:     my $constructionSpaceDir = shift;
                   2071:     my $file = shift;
                   2072:     
                   2073:     my $docroot = $Apache::lonnet::perlvar{'lonDocRoot'};
                   2074:     my $subdirpart = $constructionSpaceDir;
                   2075:     $subdirpart =~ s/^\/home\/$ENV{'user.name'}\/public_html//;
                   2076:     my $resdir = $docroot . '/res/' . $ENV{'user.domain'} . '/' . $ENV{'user.name'} .
                   2077:         $subdirpart;
                   2078: 
                   2079:     my @constructionSpaceFileStat = stat($constructionSpaceDir . '/' . $file);
                   2080:     my @resourceSpaceFileStat = stat($resdir . '/' . $file);
                   2081:     if (!@resourceSpaceFileStat) {
                   2082:         return ['Unpublished', '#FFCCCC'];
                   2083:     }
                   2084: 
                   2085:     my $constructionSpaceFileModified = $constructionSpaceFileStat[9];
                   2086:     my $resourceSpaceFileModified = $resourceSpaceFileStat[9];
                   2087:     
                   2088:     if ($constructionSpaceFileModified > $resourceSpaceFileModified) {
                   2089:         return ['Modified', '#FFFFCC'];
                   2090:     }
                   2091:     return ['Published', '#CCFFCC'];
1.4       bowersj2 2092: }
1.5       bowersj2 2093: 
1.4       bowersj2 2094: sub postprocess {
                   2095:     my $self = shift;
1.6       bowersj2 2096:     my $result = $ENV{'form.' . $self->{'variable'} . '.forminput'};
                   2097:     if (!$result) {
                   2098:         $self->{ERROR_MSG} = 'You must choose at least one file '.
                   2099:             'to continue.';
                   2100:         return 0;
                   2101:     }
                   2102: 
1.5       bowersj2 2103:     if (defined($self->{NEXTSTATE})) {
                   2104:         $helper->changeState($self->{NEXTSTATE});
1.3       bowersj2 2105:     }
1.6       bowersj2 2106: 
                   2107:     return 1;
1.3       bowersj2 2108: }
1.8       bowersj2 2109: 
                   2110: 1;
                   2111: 
1.11      bowersj2 2112: package Apache::lonhelper::section;
                   2113: 
                   2114: =pod
                   2115: 
                   2116: =head2 Element: section
                   2117: 
                   2118: <section> allows the user to choose one or more sections from the current
                   2119: course.
                   2120: 
                   2121: It takes the standard attributes "variable", "multichoice", and
                   2122: "nextstate", meaning what they do for most other elements.
                   2123: 
                   2124: =cut
                   2125: 
                   2126: no strict;
                   2127: @ISA = ("Apache::lonhelper::choices");
                   2128: use strict;
                   2129: 
                   2130: BEGIN {
                   2131:     &Apache::lonhelper::register('Apache::lonhelper::section',
                   2132:                                  ('section'));
                   2133: }
                   2134: 
                   2135: sub new {
                   2136:     my $ref = Apache::lonhelper::choices->new();
                   2137:     bless($ref);
                   2138: }
                   2139: 
                   2140: sub start_section {
                   2141:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   2142: 
                   2143:     if ($target ne 'helper') {
                   2144:         return '';
                   2145:     }
1.12      bowersj2 2146: 
                   2147:     $paramHash->{CHOICES} = [];
                   2148: 
1.11      bowersj2 2149:     $paramHash->{'variable'} = $token->[2]{'variable'};
                   2150:     $helper->declareVar($paramHash->{'variable'});
                   2151:     $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
                   2152:     if (defined($token->[2]{'nextstate'})) {
1.12      bowersj2 2153:         $paramHash->{NEXTSTATE} = $token->[2]{'nextstate'};
1.11      bowersj2 2154:     }
                   2155: 
                   2156:     # Populate the CHOICES element
                   2157:     my %choices;
                   2158: 
                   2159:     my $section = Apache::loncoursedata::CL_SECTION();
                   2160:     my $classlist = Apache::loncoursedata::get_classlist();
                   2161:     foreach (keys %$classlist) {
                   2162:         my $sectionName = $classlist->{$_}->[$section];
                   2163:         if (!$sectionName) {
                   2164:             $choices{"No section assigned"} = "";
                   2165:         } else {
                   2166:             $choices{$sectionName} = $sectionName;
                   2167:         }
1.12      bowersj2 2168:     } 
                   2169:    
1.11      bowersj2 2170:     for my $sectionName (sort(keys(%choices))) {
1.12      bowersj2 2171:         
1.11      bowersj2 2172:         push @{$paramHash->{CHOICES}}, [$sectionName, $sectionName];
                   2173:     }
                   2174: }    
                   2175: 
1.12      bowersj2 2176: sub end_section {
                   2177:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1.11      bowersj2 2178: 
1.12      bowersj2 2179:     if ($target ne 'helper') {
                   2180:         return '';
                   2181:     }
                   2182:     Apache::lonhelper::section->new();
                   2183: }    
1.11      bowersj2 2184: 1;
                   2185: 
1.8       bowersj2 2186: package Apache::lonhelper::general;
                   2187: 
                   2188: =pod
                   2189: 
                   2190: =head2 General-purpose tag: <exec>
                   2191: 
                   2192: The contents of the exec tag are executed as Perl code, not inside a 
                   2193: safe space, so the full range of $ENV and such is available. The code
                   2194: will be executed as a subroutine wrapped with the following code:
                   2195: 
                   2196: "sub { my $helper = shift; my $state = shift;" and
                   2197: 
                   2198: "}"
                   2199: 
                   2200: The return value is ignored.
                   2201: 
                   2202: $helper is the helper object. Feel free to add methods to the helper
                   2203: object to support whatever manipulation you may need to do (for instance,
                   2204: overriding the form location if the state is the final state; see 
                   2205: lonparm.helper for an example).
                   2206: 
                   2207: $state is the $paramHash that has currently been generated and may
                   2208: be manipulated by the code in exec. Note that the $state is not yet
                   2209: an actual state B<object>, it is just a hash, so do not expect to
                   2210: be able to call methods on it.
                   2211: 
                   2212: =cut
                   2213: 
                   2214: BEGIN {
                   2215:     &Apache::lonhelper::register('Apache::lonhelper::general',
1.11      bowersj2 2216:                                  'exec', 'condition', 'clause',
                   2217:                                  'eval');
1.8       bowersj2 2218: }
                   2219: 
                   2220: sub start_exec {
                   2221:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   2222: 
                   2223:     if ($target ne 'helper') {
                   2224:         return '';
                   2225:     }
                   2226:     
                   2227:     my $code = &Apache::lonxml::get_all_text('/exec', $parser);
                   2228:     
                   2229:     $code = eval ('sub { my $helper = shift; my $state = shift; ' .
                   2230:         $code . "}");
1.11      bowersj2 2231:     die 'Error in <exec>, Perl said: '. $@ if $@;
1.8       bowersj2 2232:     &$code($helper, $paramHash);
                   2233: }
                   2234: 
                   2235: sub end_exec { return ''; }
                   2236: 
                   2237: =pod
                   2238: 
                   2239: =head2 General-purpose tag: <condition>
                   2240: 
                   2241: The <condition> tag allows you to mask out parts of the helper code
                   2242: depending on some programatically determined condition. The condition
                   2243: tag contains a tag <clause> which contains perl code that when wrapped
                   2244: with "sub { my $helper = shift; my $state = shift; " and "}", returns
                   2245: a true value if the XML in the condition should be evaluated as a normal
                   2246: part of the helper, or false if it should be completely discarded.
                   2247: 
                   2248: The <clause> tag must be the first sub-tag of the <condition> tag or
                   2249: it will not work as expected.
                   2250: 
                   2251: =cut
                   2252: 
                   2253: # The condition tag just functions as a marker, it doesn't have
                   2254: # to "do" anything. Technically it doesn't even have to be registered
                   2255: # with the lonxml code, but I leave this here to be explicit about it.
                   2256: sub start_condition { return ''; }
                   2257: sub end_condition { return ''; }
                   2258: 
                   2259: sub start_clause {
                   2260:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   2261: 
                   2262:     if ($target ne 'helper') {
                   2263:         return '';
                   2264:     }
                   2265:     
                   2266:     my $clause = Apache::lonxml::get_all_text('/clause', $parser);
                   2267:     $clause = eval('sub { my $helper = shift; my $state = shift; '
                   2268:         . $clause . '}');
1.11      bowersj2 2269:     die 'Error in clause of condition, Perl said: ' . $@ if $@;
1.8       bowersj2 2270:     if (!&$clause($helper, $paramHash)) {
                   2271:         # Discard all text until the /condition.
                   2272:         &Apache::lonxml::get_all_text('/condition', $parser);
                   2273:     }
                   2274: }
                   2275: 
                   2276: sub end_clause { return ''; }
1.11      bowersj2 2277: 
                   2278: =pod
                   2279: 
                   2280: =head2 General-purpose tag: <eval>
                   2281: 
                   2282: The <eval> tag will be evaluated as a subroutine call passed in the
                   2283: current helper object and state hash as described in <condition> above,
                   2284: but is expected to return a string to be printed directly to the
                   2285: screen. This is useful for dynamically generating messages. 
                   2286: 
                   2287: =cut
                   2288: 
                   2289: # This is basically a type of message.
                   2290: # Programmatically setting $paramHash->{NEXTSTATE} would work, though
                   2291: # it's probably bad form.
                   2292: 
                   2293: sub start_eval {
                   2294:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   2295: 
                   2296:     if ($target ne 'helper') {
                   2297:         return '';
                   2298:     }
                   2299:     
                   2300:     my $program = Apache::lonxml::get_all_text('/eval', $parser);
                   2301:     $program = eval('sub { my $helper = shift; my $state = shift; '
                   2302:         . $program . '}');
                   2303:     die 'Error in eval code, Perl said: ' . $@ if $@;
                   2304:     $paramHash->{MESSAGE_TEXT} = &$program($helper, $paramHash);
                   2305: }
                   2306: 
                   2307: sub end_eval { 
                   2308:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   2309: 
                   2310:     if ($target ne 'helper') {
                   2311:         return '';
                   2312:     }
                   2313: 
                   2314:     Apache::lonhelper::message->new();
                   2315: }
                   2316: 
1.13      bowersj2 2317: 1;
                   2318: 
1.27      bowersj2 2319: package Apache::lonhelper::final;
                   2320: 
                   2321: =pod
                   2322: 
                   2323: =head2 Element: final
                   2324: 
                   2325: <final> is a special element that works with helpers that use the <finalcode>
                   2326: tag. It goes through all the states and elements, executing the <finalcode>
                   2327: snippets and collecting the results. Finally, it takes the user out of the
                   2328: helper, going to a provided page.
                   2329: 
                   2330: =cut
                   2331: 
                   2332: no strict;
                   2333: @ISA = ("Apache::lonhelper::element");
                   2334: use strict;
                   2335: 
                   2336: BEGIN {
                   2337:     &Apache::lonhelper::register('Apache::lonhelper::final',
                   2338:                                  ('final', 'exitpage'));
                   2339: }
                   2340: 
                   2341: sub new {
                   2342:     my $ref = Apache::lonhelper::element->new();
                   2343:     bless($ref);
                   2344: }
                   2345: 
                   2346: sub start_final { return ''; }
                   2347: 
                   2348: sub end_final {
                   2349:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   2350: 
                   2351:     if ($target ne 'helper') {
                   2352:         return '';
                   2353:     }
                   2354: 
                   2355:     Apache::lonhelper::final->new();
                   2356:    
                   2357:     return '';
                   2358: }
                   2359: 
                   2360: sub start_exitpage {
                   2361:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   2362: 
                   2363:     if ($target ne 'helper') {
                   2364:         return '';
                   2365:     }
                   2366: 
                   2367:     $paramHash->{EXIT_PAGE} = &Apache::lonxml::get_all_text('/exitpage',
                   2368:                                                             $parser);
                   2369: 
                   2370:     return '';
                   2371: }
                   2372: 
                   2373: sub end_exitpage { return ''; }
                   2374: 
                   2375: sub render {
                   2376:     my $self = shift;
                   2377: 
                   2378:     my @results;
                   2379: 
                   2380:     # Collect all the results
                   2381:     for my $stateName (keys %{$helper->{STATES}}) {
                   2382:         my $state = $helper->{STATES}->{$stateName};
                   2383:         
                   2384:         for my $element (@{$state->{ELEMENTS}}) {
                   2385:             if (defined($element->{FINAL_CODE})) {
                   2386:                 # Compile the code.
                   2387:                 my $code = 'sub { my $helper = shift; ' . $element->{FINAL_CODE} .
                   2388:                     '}';
                   2389:                 $code = eval($code);
                   2390:                 die 'Error while executing final code for element with var ' .
                   2391:                     $element->{'variable'} . ', Perl said: ' . $@ if $@;
                   2392: 
                   2393:                 my $result = &$code($helper);
                   2394:                 if ($result) {
                   2395:                     push @results, $result;
                   2396:                 }
                   2397:             }
                   2398:         }
                   2399:     }
                   2400: 
                   2401:     if (scalar(@results) == 0) {
                   2402:         return '';
                   2403:     }
                   2404: 
                   2405:     my $result = "<ul>\n";
                   2406:     for my $re (@results) {
                   2407:         $result .= '    <li>' . $re . "</li>\n";
                   2408:     }
                   2409:     return $result . '</ul>';
                   2410: }
                   2411: 
                   2412: 1;
                   2413: 
1.13      bowersj2 2414: package Apache::lonhelper::parmwizfinal;
                   2415: 
                   2416: # This is the final state for the parmwizard. It is not generally useful,
                   2417: # so it is not perldoc'ed. It does its own processing.
                   2418: # It is represented with <parmwizfinal />, and
                   2419: # should later be moved to lonparmset.pm .
                   2420: 
                   2421: no strict;
                   2422: @ISA = ('Apache::lonhelper::element');
                   2423: use strict;
1.11      bowersj2 2424: 
1.13      bowersj2 2425: BEGIN {
                   2426:     &Apache::lonhelper::register('Apache::lonhelper::parmwizfinal',
                   2427:                                  ('parmwizfinal'));
                   2428: }
                   2429: 
                   2430: use Time::localtime;
                   2431: 
                   2432: sub new {
                   2433:     my $ref = Apache::lonhelper::choices->new();
                   2434:     bless ($ref);
                   2435: }
                   2436: 
                   2437: sub start_parmwizfinal { return ''; }
                   2438: 
                   2439: sub end_parmwizfinal {
                   2440:     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
                   2441: 
                   2442:     if ($target ne 'helper') {
                   2443:         return '';
                   2444:     }
                   2445:     Apache::lonhelper::parmwizfinal->new();
                   2446: }
                   2447: 
                   2448: # Renders a form that, when submitted, will form the input to lonparmset.pm
                   2449: sub render {
                   2450:     my $self = shift;
                   2451:     my $vars = $helper->{VARS};
                   2452: 
                   2453:     # FIXME: Unify my designators with the standard ones
                   2454:     my %dateTypeHash = ('open_date' => "Opening Date",
                   2455:                         'due_date' => "Due Date",
                   2456:                         'answer_date' => "Answer Date");
                   2457:     my %parmTypeHash = ('open_date' => "0_opendate",
                   2458:                         'due_date' => "0_duedate",
                   2459:                         'answer_date' => "0_answerdate");
                   2460:     
                   2461:     my $affectedResourceId = "";
                   2462:     my $parm_name = $parmTypeHash{$vars->{ACTION_TYPE}};
                   2463:     my $level = "";
1.27      bowersj2 2464:     my $resourceString;
                   2465:     my $symb;
                   2466:     my $paramlevel;
                   2467: 
1.13      bowersj2 2468:     # Print the granularity, depending on the action
                   2469:     if ($vars->{GRANULARITY} eq 'whole_course') {
1.27      bowersj2 2470:         $resourceString .= '<li>for <b>all resources in the course</b></li>';
1.13      bowersj2 2471:         $level = 9; # general course, see lonparmset.pm perldoc
                   2472:         $affectedResourceId = "0.0";
1.27      bowersj2 2473:         $symb = 'a';
                   2474:         $paramlevel = 'general';
1.13      bowersj2 2475:     } elsif ($vars->{GRANULARITY} eq 'map') {
                   2476:         my $navmap = Apache::lonnavmaps::navmap->new(
                   2477:                            $ENV{"request.course.fn"}.".db",
                   2478:                            $ENV{"request.course.fn"}."_parms.db", 0, 0);
                   2479:         my $res = $navmap->getById($vars->{RESOURCE_ID});
                   2480:         my $title = $res->compTitle();
1.27      bowersj2 2481:         $symb = $res->symb();
1.13      bowersj2 2482:         $navmap->untieHashes();
1.27      bowersj2 2483:         $resourceString .= "<li>for the map named <b>$title</b></li>";
1.13      bowersj2 2484:         $level = 8;
                   2485:         $affectedResourceId = $vars->{RESOURCE_ID};
1.27      bowersj2 2486:         $paramlevel = 'map';
1.13      bowersj2 2487:     } else {
                   2488:         my $navmap = Apache::lonnavmaps::navmap->new(
                   2489:                            $ENV{"request.course.fn"}.".db",
                   2490:                            $ENV{"request.course.fn"}."_parms.db", 0, 0);
                   2491:         my $res = $navmap->getById($vars->{RESOURCE_ID});
1.27      bowersj2 2492:         $symb = $res->symb();
1.13      bowersj2 2493:         my $title = $res->compTitle();
                   2494:         $navmap->untieHashes();
1.27      bowersj2 2495:         $resourceString .= "<li>for the resource named <b>$title</b></li>";
1.13      bowersj2 2496:         $level = 7;
                   2497:         $affectedResourceId = $vars->{RESOURCE_ID};
1.27      bowersj2 2498:         $paramlevel = 'full';
1.13      bowersj2 2499:     }
                   2500: 
1.27      bowersj2 2501:     my $result = "<form name='helpform' method='get' action='/adm/parmset#$affectedResourceId&$parm_name&$level'>\n";
                   2502:     $result .= '<p>Confirm that this information is correct, then click &quot;Finish Wizard&quot; to complete setting the parameter.<ul>';
                   2503:     
                   2504:     # Print the type of manipulation:
                   2505:     $result .= '<li>Setting the <b>' . $dateTypeHash{$vars->{ACTION_TYPE}}
                   2506:                . "</b></li>\n";
                   2507:     if ($vars->{ACTION_TYPE} eq 'due_date' || 
                   2508:         $vars->{ACTION_TYPE} eq 'answer_date') {
                   2509:         # for due dates, we default to "date end" type entries
                   2510:         $result .= "<input type='hidden' name='recent_date_end' " .
                   2511:             "value='" . $vars->{PARM_DATE} . "' />\n";
                   2512:         $result .= "<input type='hidden' name='pres_value' " . 
                   2513:             "value='" . $vars->{PARM_DATE} . "' />\n";
                   2514:         $result .= "<input type='hidden' name='pres_type' " .
                   2515:             "value='date_end' />\n";
                   2516:     } elsif ($vars->{ACTION_TYPE} eq 'open_date') {
                   2517:         $result .= "<input type='hidden' name='recent_date_start' ".
                   2518:             "value='" . $vars->{PARM_DATE} . "' />\n";
                   2519:         $result .= "<input type='hidden' name='pres_value' " .
                   2520:             "value='" . $vars->{PARM_DATE} . "' />\n";
                   2521:         $result .= "<input type='hidden' name='pres_type' " .
                   2522:             "value='date_start' />\n";
                   2523:     } 
                   2524: 
                   2525:     $result .= $resourceString;
                   2526:     
1.13      bowersj2 2527:     # Print targets
                   2528:     if ($vars->{TARGETS} eq 'course') {
                   2529:         $result .= '<li>for <b>all students in course</b></li>';
                   2530:     } elsif ($vars->{TARGETS} eq 'section') {
                   2531:         my $section = $vars->{SECTION_NAME};
                   2532:         $result .= "<li>for section <b>$section</b></li>";
                   2533:         $level -= 3;
                   2534:         $result .= "<input type='hidden' name='csec' value='" .
                   2535:             HTML::Entities::encode($section) . "' />\n";
                   2536:     } else {
                   2537:         # FIXME: This is probably wasteful! Store the name!
                   2538:         my $classlist = Apache::loncoursedata::get_classlist();
1.27      bowersj2 2539:         my $username = $vars->{USER_NAME};
                   2540:         # Chop off everything after the last colon (section)
                   2541:         $username = substr($username, 0, rindex($username, ':'));
                   2542:         my $name = $classlist->{$username}->[6];
1.13      bowersj2 2543:         $result .= "<li>for <b>$name</b></li>";
                   2544:         $level -= 6;
                   2545:         my ($uname, $udom) = split /:/, $vars->{USER_NAME};
                   2546:         $result .= "<input type='hidden' name='uname' value='".
                   2547:             HTML::Entities::encode($uname) . "' />\n";
                   2548:         $result .= "<input type='hidden' name='udom' value='".
                   2549:             HTML::Entities::encode($udom) . "' />\n";
                   2550:     }
                   2551: 
                   2552:     # Print value
                   2553:     $result .= "<li>to <b>" . ctime($vars->{PARM_DATE}) . "</b> (" .
                   2554:         Apache::lonnavmaps::timeToHumanString($vars->{PARM_DATE}) 
                   2555:         . ")</li>\n";
                   2556: 
                   2557:     # print pres_marker
                   2558:     $result .= "\n<input type='hidden' name='pres_marker'" .
                   2559:         " value='$affectedResourceId&$parm_name&$level' />\n";
1.27      bowersj2 2560:     
                   2561:     # Make the table appear
                   2562:     $result .= "\n<input type='hidden' value='true' name='prevvisit' />";
                   2563:     $result .= "\n<input type='hidden' value='all' name='pschp' />";
                   2564:     $result .= "\n<input type='hidden' value='$symb' name='pssymb' />";
                   2565:     $result .= "\n<input type='hidden' value='$paramlevel' name='parmlev' />";
1.13      bowersj2 2566: 
                   2567:     $result .= "<br /><br /><center><input type='submit' value='Finish Helper' /></center></form>\n";
                   2568: 
                   2569:     return $result;
                   2570: }
                   2571:     
                   2572: sub overrideForm {
                   2573:     return 1;
                   2574: }
1.5       bowersj2 2575: 
1.4       bowersj2 2576: 1;
1.3       bowersj2 2577: 
1.1       bowersj2 2578: __END__
1.3       bowersj2 2579: 

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