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[LON-CAPA] /
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lonhelper.pm
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Thu May 8 19:52:43 2003 UTC (21 years, 3 months ago) by
bowersj2
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* Fixed heisenbug that caused wierd stuff to happen if the handler
tried to access file-scoped variables. See lengthy comment at the
beginning of the commit message for a discussion; feel free to discuss
it with me if it still doesn't make sense. (I think this may have had
something to do with the global variable troubles in the past.)
* Added "finalcode" and "defaultvalue" tags, intended for use in the
course initialization helper. <choices> now respects <defaultvalue>.
* If there are fewer then five choices in a multi-choice <choice>, don't
display the "Select All" and "Unselect All" buttons, as they are
visually clumsy.
1: # The LearningOnline Network with CAPA
2: # .helper XML handler to implement the LON-CAPA helper
3: #
4: # $Id: lonhelper.pm,v 1.25 2003/05/08 19:52:43 bowersj2 Exp $
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:
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
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
63: will start with. By convention, this state should clearly describe what
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:
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: $paramHash = Apache::lonhelper::getParamHash();
135:
136: and you can repeat creating elements that way. You can add states
137: and elements as needed.
138:
139: See lonprintout.pm, subroutine printHelper for an example of this, where
140: we dynamically add some states to prevent security problems, for instance.
141:
142: Normally the machinery in the XML format is sufficient; dynamically
143: adding states can easily be done by wrapping the state in a <condition>
144: tag. This should only be used when the code dominates the XML content,
145: the code is so complicated that it is difficult to get access to
146: all of the information you need because of scoping issues, or so much
147: of the information used is persistent because would-be <exec> or
148: <eval> blocks that using the {DATA} mechanism results in hard-to-read
149: and -maintain code.
150:
151: It is possible to do some of the work with an XML fragment parsed by
152: lonxml; again, see lonprintout.pm for an example. In that case it is
153: imperative that you call B<Apache::lonhelper::registerHelperTags()>
154: before parsing XML fragments and B<Apache::lonhelper::unregisterHelperTags()>
155: when you are done. See lonprintout.pm for examples of this usage in the
156: printHelper subroutine.
157:
158: =cut
159:
160: package Apache::lonhelper;
161: use Apache::Constants qw(:common);
162: use Apache::File;
163: use Apache::lonxml;
164:
165: # Register all the tags with the helper, so the helper can
166: # push and pop them
167:
168: my @helperTags;
169:
170: sub register {
171: my ($namespace, @tags) = @_;
172:
173: for my $tag (@tags) {
174: push @helperTags, [$namespace, $tag];
175: }
176: }
177:
178: BEGIN {
179: Apache::lonxml::register('Apache::lonhelper',
180: ('helper'));
181: register('Apache::lonhelper', ('state'));
182: }
183:
184: # Since all helpers are only three levels deep (helper tag, state tag,
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;
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;
195:
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:
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.
227: sub real_handler {
228: my $r = shift;
229: my $uri = shift;
230: if (!defined($uri)) { $uri = $r->uri(); }
231: $ENV{'request.uri'} = $uri;
232: my $filename = '/home/httpd/html' . $uri;
233: my $fh = Apache::File->new($filename);
234: my $file;
235: read $fh, $file, 100000000;
236:
237: # Send header, don't cache this page
238: if ($r->header_only) {
239: if ($ENV{'browser.mathml'}) {
240: $r->content_type('text/xml');
241: } else {
242: $r->content_type('text/html');
243: }
244: $r->send_http_header;
245: return OK;
246: }
247: if ($ENV{'browser.mathml'}) {
248: $r->content_type('text/xml');
249: } else {
250: $r->content_type('text/html');
251: }
252: $r->send_http_header;
253: $r->rflush();
254:
255: # Discard result, we just want the objects that get created by the
256: # xml parsing
257: &Apache::lonxml::xmlparse($r, 'helper', $file);
258:
259: $helper->process();
260:
261: $r->print($helper->display());
262: return OK;
263: }
264:
265: sub registerHelperTags {
266: for my $tagList (@helperTags) {
267: Apache::lonxml::register($tagList->[0], $tagList->[1]);
268: }
269: }
270:
271: sub unregisterHelperTags {
272: for my $tagList (@helperTags) {
273: Apache::lonxml::deregister($tagList->[0], $tagList->[1]);
274: }
275: }
276:
277: sub start_helper {
278: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
279:
280: if ($target ne 'helper') {
281: return '';
282: }
283:
284: registerHelperTags();
285:
286: Apache::lonhelper::helper->new($token->[2]{'title'});
287: return '';
288: }
289:
290: sub end_helper {
291: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
292:
293: if ($target ne 'helper') {
294: return '';
295: }
296:
297: unregisterHelperTags();
298:
299: return '';
300: }
301:
302: sub start_state {
303: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
304:
305: if ($target ne 'helper') {
306: return '';
307: }
308:
309: Apache::lonhelper::state->new($token->[2]{'name'},
310: $token->[2]{'title'});
311: return '';
312: }
313:
314: # Use this to get the param hash from other files.
315: sub getParamHash {
316: return $paramHash;
317: }
318:
319: # Use this to get the helper, if implementing elements in other files
320: # (like lonprintout.pm)
321: sub getHelper {
322: return $helper;
323: }
324:
325: # don't need this, so ignore it
326: sub end_state {
327: return '';
328: }
329:
330: 1;
331:
332: package Apache::lonhelper::helper;
333:
334: use Digest::MD5 qw(md5_hex);
335: use HTML::Entities;
336: use Apache::loncommon;
337: use Apache::File;
338:
339: sub new {
340: my $proto = shift;
341: my $class = ref($proto) || $proto;
342: my $self = {};
343:
344: $self->{TITLE} = shift;
345:
346: Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING});
347:
348: # If there is a state from the previous form, use that. If there is no
349: # state, use the start state parameter.
350: if (defined $ENV{"form.CURRENT_STATE"})
351: {
352: $self->{STATE} = $ENV{"form.CURRENT_STATE"};
353: }
354: else
355: {
356: $self->{STATE} = "START";
357: }
358:
359: $self->{TOKEN} = $ENV{'form.TOKEN'};
360: # If a token was passed, we load that in. Otherwise, we need to create a
361: # new storage file
362: # Tried to use standard Tie'd hashes, but you can't seem to take a
363: # reference to a tied hash and write to it. I'd call that a wart.
364: if ($self->{TOKEN}) {
365: # Validate the token before trusting it
366: if ($self->{TOKEN} !~ /^[a-f0-9]{32}$/) {
367: # Not legit. Return nothing and let all hell break loose.
368: # User shouldn't be doing that!
369: return undef;
370: }
371:
372: # Get the hash.
373: $self->{FILENAME} = $Apache::lonnet::tmpdir . md5_hex($self->{TOKEN}); # Note the token is not the literal file
374:
375: my $file = Apache::File->new($self->{FILENAME});
376: my $contents = <$file>;
377:
378: # Now load in the contents
379: for my $value (split (/&/, $contents)) {
380: my ($name, $value) = split(/=/, $value);
381: $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
382: $self->{VARS}->{$name} = $value;
383: }
384:
385: $file->close();
386: } else {
387: # Only valid if we're just starting.
388: if ($self->{STATE} ne 'START') {
389: return undef;
390: }
391: # Must create the storage
392: $self->{TOKEN} = md5_hex($ENV{'user.name'} . $ENV{'user.domain'} .
393: time() . rand());
394: $self->{FILENAME} = $Apache::lonnet::tmpdir . md5_hex($self->{TOKEN});
395: }
396:
397: # OK, we now have our persistent storage.
398:
399: if (defined $ENV{"form.RETURN_PAGE"})
400: {
401: $self->{RETURN_PAGE} = $ENV{"form.RETURN_PAGE"};
402: }
403: else
404: {
405: $self->{RETURN_PAGE} = $ENV{REFERER};
406: }
407:
408: $self->{STATES} = {};
409: $self->{DONE} = 0;
410:
411: # Used by various helpers for various things; see lonparm.helper
412: # for an example.
413: $self->{DATA} = {};
414:
415: $helper = $self;
416:
417: # Establish the $paramHash
418: $paramHash = {};
419:
420: bless($self, $class);
421: return $self;
422: }
423:
424: # Private function; returns a string to construct the hidden fields
425: # necessary to have the helper track state.
426: sub _saveVars {
427: my $self = shift;
428: my $result = "";
429: $result .= '<input type="hidden" name="CURRENT_STATE" value="' .
430: HTML::Entities::encode($self->{STATE}) . "\" />\n";
431: $result .= '<input type="hidden" name="TOKEN" value="' .
432: $self->{TOKEN} . "\" />\n";
433: $result .= '<input type="hidden" name="RETURN_PAGE" value="' .
434: HTML::Entities::encode($self->{RETURN_PAGE}) . "\" />\n";
435:
436: return $result;
437: }
438:
439: # Private function: Create the querystring-like representation of the stored
440: # data to write to disk.
441: sub _varsInFile {
442: my $self = shift;
443: my @vars = ();
444: for my $key (keys %{$self->{VARS}}) {
445: push @vars, &Apache::lonnet::escape($key) . '=' .
446: &Apache::lonnet::escape($self->{VARS}->{$key});
447: }
448: return join ('&', @vars);
449: }
450:
451: # Use this to declare variables.
452: # FIXME: Document this
453: sub declareVar {
454: my $self = shift;
455: my $var = shift;
456:
457: if (!defined($self->{VARS}->{$var})) {
458: $self->{VARS}->{$var} = '';
459: }
460:
461: my $envname = 'form.' . $var . '.forminput';
462: if (defined($ENV{$envname})) {
463: $self->{VARS}->{$var} = $ENV{$envname};
464: }
465: }
466:
467: sub changeState {
468: my $self = shift;
469: $self->{STATE} = shift;
470: }
471:
472: sub registerState {
473: my $self = shift;
474: my $state = shift;
475:
476: my $stateName = $state->name();
477: $self->{STATES}{$stateName} = $state;
478: }
479:
480: sub process {
481: my $self = shift;
482:
483: # Phase 1: Post processing for state of previous screen (which is actually
484: # the "current state" in terms of the helper variables), if it wasn't the
485: # beginning state.
486: if ($self->{STATE} ne "START" || $ENV{"form.SUBMIT"} eq "Next ->") {
487: my $prevState = $self->{STATES}{$self->{STATE}};
488: $prevState->postprocess();
489: }
490:
491: # Note, to handle errors in a state's input that a user must correct,
492: # do not transition in the postprocess, and force the user to correct
493: # the error.
494:
495: # Phase 2: Preprocess current state
496: my $startState = $self->{STATE};
497: my $state = $self->{STATES}->{$startState};
498:
499: # For debugging, print something here to determine if you're going
500: # to an undefined state.
501: if (!defined($state)) {
502: return;
503: }
504: $state->preprocess();
505:
506: # Phase 3: While the current state is different from the previous state,
507: # keep processing.
508: while ( $startState ne $self->{STATE} &&
509: defined($self->{STATES}->{$self->{STATE}}) )
510: {
511: $startState = $self->{STATE};
512: $state = $self->{STATES}->{$startState};
513: $state->preprocess();
514: }
515:
516: return;
517: }
518:
519: # 1: Do the post processing for the previous state.
520: # 2: Do the preprocessing for the current state.
521: # 3: Check to see if state changed, if so, postprocess current and move to next.
522: # Repeat until state stays stable.
523: # 4: Render the current state to the screen as an HTML page.
524: sub display {
525: my $self = shift;
526:
527: my $state = $self->{STATES}{$self->{STATE}};
528:
529: my $result = "";
530:
531: if (!defined($state)) {
532: $result = "<font color='#ff0000'>Error: state '$state' not defined!</font>";
533: return $result;
534: }
535:
536: # Phase 4: Display.
537: my $stateTitle = $state->title();
538: my $bodytag = &Apache::loncommon::bodytag("$self->{TITLE}",'','');
539:
540: $result .= <<HEADER;
541: <html>
542: <head>
543: <title>LON-CAPA Helper: $self->{TITLE}</title>
544: </head>
545: $bodytag
546: HEADER
547: if (!$state->overrideForm()) { $result.="<form name='helpform' method='GET'>"; }
548: $result .= <<HEADER;
549: <table border="0"><tr><td>
550: <h2><i>$stateTitle</i></h2>
551: HEADER
552:
553: if (!$state->overrideForm()) {
554: $result .= $self->_saveVars();
555: }
556: $result .= $state->render() . "<p> </p>";
557:
558: if (!$state->overrideForm()) {
559: $result .= '<center>';
560: if ($self->{STATE} ne $self->{START_STATE}) {
561: #$result .= '<input name="SUBMIT" type="submit" value="<- Previous" /> ';
562: }
563: if ($self->{DONE}) {
564: my $returnPage = $self->{RETURN_PAGE};
565: $result .= "<a href=\"$returnPage\">End Helper</a>";
566: }
567: else {
568: $result .= '<input name="back" type="button" ';
569: $result .= 'value="<- Previous" onclick="history.go(-1)" /> ';
570: $result .= '<input name="SUBMIT" type="submit" value="Next ->" />';
571: }
572: $result .= "</center>\n";
573: }
574:
575: #foreach my $key (keys %{$self->{VARS}}) {
576: # $result .= "|$key| -> " . $self->{VARS}->{$key} . "<br />";
577: #}
578:
579: $result .= <<FOOTER;
580: </td>
581: </tr>
582: </table>
583: </form>
584: </body>
585: </html>
586: FOOTER
587:
588: # Handle writing out the vars to the file
589: my $file = Apache::File->new('>'.$self->{FILENAME});
590: print $file $self->_varsInFile();
591:
592: return $result;
593: }
594:
595: 1;
596:
597: package Apache::lonhelper::state;
598:
599: # States bundle things together and are responsible for compositing the
600: # various elements together. It is not generally necessary for users to
601: # use the state object directly, so it is not perldoc'ed.
602:
603: # Basically, all the states do is pass calls to the elements and aggregate
604: # the results.
605:
606: sub new {
607: my $proto = shift;
608: my $class = ref($proto) || $proto;
609: my $self = {};
610:
611: $self->{NAME} = shift;
612: $self->{TITLE} = shift;
613: $self->{ELEMENTS} = [];
614:
615: bless($self, $class);
616:
617: $helper->registerState($self);
618:
619: $state = $self;
620:
621: return $self;
622: }
623:
624: sub name {
625: my $self = shift;
626: return $self->{NAME};
627: }
628:
629: sub title {
630: my $self = shift;
631: return $self->{TITLE};
632: }
633:
634: sub preprocess {
635: my $self = shift;
636: for my $element (@{$self->{ELEMENTS}}) {
637: $element->preprocess();
638: }
639: }
640:
641: # FIXME: Document that all postprocesses must return a true value or
642: # the state transition will be overridden
643: sub postprocess {
644: my $self = shift;
645:
646: # Save the state so we can roll it back if we need to.
647: my $originalState = $helper->{STATE};
648: my $everythingSuccessful = 1;
649:
650: for my $element (@{$self->{ELEMENTS}}) {
651: my $result = $element->postprocess();
652: if (!$result) { $everythingSuccessful = 0; }
653: }
654:
655: # If not all the postprocesses were successful, override
656: # any state transitions that may have occurred. It is the
657: # responsibility of the states to make sure they have
658: # error handling in that case.
659: if (!$everythingSuccessful) {
660: $helper->{STATE} = $originalState;
661: }
662: }
663:
664: # Override the form if any element wants to.
665: # two elements overriding the form will make a mess, but that should
666: # be considered helper author error ;-)
667: sub overrideForm {
668: my $self = shift;
669: for my $element (@{$self->{ELEMENTS}}) {
670: if ($element->overrideForm()) {
671: return 1;
672: }
673: }
674: return 0;
675: }
676:
677: sub addElement {
678: my $self = shift;
679: my $element = shift;
680:
681: push @{$self->{ELEMENTS}}, $element;
682: }
683:
684: sub render {
685: my $self = shift;
686: my @results = ();
687:
688: for my $element (@{$self->{ELEMENTS}}) {
689: push @results, $element->render();
690: }
691: return join("\n", @results);
692: }
693:
694: 1;
695:
696: package Apache::lonhelper::element;
697: # Support code for elements
698:
699: =pod
700:
701: =head2 Element Base Class
702:
703: The Apache::lonhelper::element base class provides support methods for
704: the elements to use, such as a multiple value processer.
705:
706: B<Methods>:
707:
708: =over 4
709:
710: =item * process_multiple_choices(formName, varName): Process the form
711: element named "formName" and place the selected items into the helper
712: variable named varName. This is for things like checkboxes or
713: multiple-selection listboxes where the user can select more then
714: one entry. The selected entries are delimited by triple pipes in
715: the helper variables, like this:
716:
717: CHOICE_1|||CHOICE_2|||CHOICE_3
718:
719: =back
720:
721: B<finalcode tag>
722:
723: Each element can contain a "finalcode" tag that, when the special FINAL
724: helper state is used, will be executed, surrounded by "sub { my $helper = shift;"
725: and "}". It is expected to return a string describing what it did, which
726: may be an empty string. See course initialization helper for an example. This is
727: generally intended for helpers like the course initialization helper, which consist
728: of several panels, each of which is performing some sort of bite-sized functionality.
729:
730: B<defaultvalue tag>
731:
732: Each element that accepts user input can contain a "defaultvalue" tag that,
733: when surrounded by "sub { my $helper = shift; my $state = shift; " and "}",
734: will form a subroutine that when called will provide a default value for
735: the element. How this value is interpreted by the element is specific to
736: the element itself, and possibly the settings the element has (such as
737: multichoice vs. single choice for <choices> tags).
738:
739: This is also intended for things like the course initialization wizard, where the
740: user is setting various parameters. By correctly grabbing current settings
741: and including them into the helper, it allows the user to come back to the
742: helper later and re-execute it, without needing to worry about overwriting
743: some setting accidentally.
744:
745: Again, see the course initialization helper for examples.
746:
747: =cut
748:
749: BEGIN {
750: &Apache::lonhelper::register('Apache::lonhelper::element',
751: ('nextstate', 'finalcode',
752: 'defaultvalue'));
753: }
754:
755: # Because we use the param hash, this is often a sufficent
756: # constructor
757: sub new {
758: my $proto = shift;
759: my $class = ref($proto) || $proto;
760: my $self = $paramHash;
761: bless($self, $class);
762:
763: $self->{PARAMS} = $paramHash;
764: $self->{STATE} = $state;
765: $state->addElement($self);
766:
767: # Ensure param hash is not reused
768: $paramHash = {};
769:
770: return $self;
771: }
772:
773: sub start_nextstate {
774: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
775:
776: if ($target ne 'helper') {
777: return '';
778: }
779:
780: $paramHash->{NEXTSTATE} = &Apache::lonxml::get_all_text('/nextstate',
781: $parser);
782: return '';
783: }
784:
785: sub end_nextstate { return ''; }
786:
787: sub start_finalcode {
788: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
789:
790: if ($target ne 'helper') {
791: return '';
792: }
793:
794: $paramHash->{FINAL_CODE} = &Apache::lonxml::get_all_text('/finalcode',
795: $parser);
796: return '';
797: }
798:
799: sub end_finalcode { return ''; }
800:
801: sub start_defaultvalue {
802: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
803:
804: if ($target ne 'helper') {
805: return '';
806: }
807:
808: $paramHash->{DEFAULT_VALUE} = &Apache::lonxml::get_all_text('/defaultvalue',
809: $parser);
810: $paramHash->{DEFAULT_VALUE} = 'sub { my $helper = shift; my $state = shift;' .
811: $paramHash->{DEFAULT_VALUE} . '}';
812: return '';
813: }
814:
815: sub end_defaultvalue { return ''; }
816:
817: sub preprocess {
818: return 1;
819: }
820:
821: sub postprocess {
822: return 1;
823: }
824:
825: sub render {
826: return '';
827: }
828:
829: sub overrideForm {
830: return 0;
831: }
832:
833: sub process_multiple_choices {
834: my $self = shift;
835: my $formname = shift;
836: my $var = shift;
837:
838: # Must extract values from data directly, as there
839: # may be more then one.
840: my @values;
841: for my $formparam (split (/&/, $ENV{QUERY_STRING})) {
842: my ($name, $value) = split(/=/, $formparam);
843: if ($name ne $formname) {
844: next;
845: }
846: $value =~ tr/+/ /;
847: $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
848: push @values, $value;
849: }
850: $helper->{VARS}->{$var} = join('|||', @values);
851:
852: return;
853: }
854:
855: 1;
856:
857: package Apache::lonhelper::message;
858:
859: =pod
860:
861: =head2 Element: message
862:
863: Message elements display the contents of their <message_text> tags, and
864: transition directly to the state in the <nextstate> tag. Example:
865:
866: <message>
867: <nextstate>GET_NAME</nextstate>
868: <message_text>This is the <b>message</b> the user will see,
869: <i>HTML allowed</i>.</message_text>
870: </message>
871:
872: This will display the HTML message and transition to the <nextstate> if
873: given. The HTML will be directly inserted into the helper, so if you don't
874: want text to run together, you'll need to manually wrap the <message_text>
875: in <p> tags, or whatever is appropriate for your HTML.
876:
877: Message tags do not add in whitespace, so if you want it, you'll need to add
878: it into states. This is done so you can inline some elements, such as
879: the <date> element, right between two messages, giving the appearence that
880: the <date> element appears inline. (Note the elements can not be embedded
881: within each other.)
882:
883: This is also a good template for creating your own new states, as it has
884: very little code beyond the state template.
885:
886: =cut
887:
888: no strict;
889: @ISA = ("Apache::lonhelper::element");
890: use strict;
891:
892: BEGIN {
893: &Apache::lonhelper::register('Apache::lonhelper::message',
894: ('message'));
895: }
896:
897: sub new {
898: my $ref = Apache::lonhelper::element->new();
899: bless($ref);
900: }
901:
902: # CONSTRUCTION: Construct the message element from the XML
903: sub start_message {
904: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
905:
906: if ($target ne 'helper') {
907: return '';
908: }
909:
910: $paramHash->{MESSAGE_TEXT} = &Apache::lonxml::get_all_text('/message',
911: $parser);
912:
913: if (defined($token->[2]{'nextstate'})) {
914: $paramHash->{NEXTSTATE} = $token->[2]{'nextstate'};
915: }
916: return '';
917: }
918:
919: sub end_message {
920: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
921:
922: if ($target ne 'helper') {
923: return '';
924: }
925: Apache::lonhelper::message->new();
926: return '';
927: }
928:
929: sub render {
930: my $self = shift;
931:
932: return $self->{MESSAGE_TEXT};
933: }
934: # If a NEXTSTATE was given, switch to it
935: sub postprocess {
936: my $self = shift;
937: if (defined($self->{NEXTSTATE})) {
938: $helper->changeState($self->{NEXTSTATE});
939: }
940:
941: return 1;
942: }
943: 1;
944:
945: package Apache::lonhelper::choices;
946:
947: =pod
948:
949: =head2 Element: choices
950:
951: Choice states provide a single choice to the user as a text selection box.
952: A "choice" is two pieces of text, one which will be displayed to the user
953: (the "human" value), and one which will be passed back to the program
954: (the "computer" value). For instance, a human may choose from a list of
955: resources on disk by title, while your program wants the file name.
956:
957: <choices> takes an attribute "variable" to control which helper variable
958: the result is stored in.
959:
960: <choices> takes an attribute "multichoice" which, if set to a true
961: value, will allow the user to select multiple choices.
962:
963: B<SUB-TAGS>
964:
965: <choices> can have the following subtags:
966:
967: =over 4
968:
969: =item * <nextstate>state_name</nextstate>: If given, this will cause the
970: choice element to transition to the given state after executing. If
971: this is used, do not pass nextstates to the <choice> tag.
972:
973: =item * <choice />: If the choices are static,
974: this element will allow you to specify them. Each choice
975: contains attribute, "computer", as described above. The
976: content of the tag will be used as the human label.
977: For example,
978: <choice computer='234-12-7312'>Bobby McDormik</choice>.
979:
980: <choice> can take a parameter "eval", which if set to
981: a true value, will cause the contents of the tag to be
982: evaluated as it would be in an <eval> tag; see <eval> tag
983: below.
984:
985: <choice> may optionally contain a 'nextstate' attribute, which
986: will be the state transisitoned to if the choice is made, if
987: the choice is not multichoice.
988:
989: =back
990:
991: To create the choices programmatically, either wrap the choices in
992: <condition> tags (prefered), or use an <exec> block inside the <choice>
993: tag. Store the choices in $state->{CHOICES}, which is a list of list
994: references, where each list has three strings. The first is the human
995: name, the second is the computer name. and the third is the option
996: next state. For example:
997:
998: <exec>
999: for (my $i = 65; $i < 65 + 26; $i++) {
1000: push @{$state->{CHOICES}}, [chr($i), $i, 'next'];
1001: }
1002: </exec>
1003:
1004: This will allow the user to select from the letters A-Z (in ASCII), while
1005: passing the ASCII value back into the helper variables, and the state
1006: will in all cases transition to 'next'.
1007:
1008: You can mix and match methods of creating choices, as long as you always
1009: "push" onto the choice list, rather then wiping it out. (You can even
1010: remove choices programmatically, but that would probably be bad form.)
1011:
1012: B<defaultvalue support>
1013:
1014: Choices supports default values both in multichoice and single choice mode.
1015: In single choice mode, have the defaultvalue tag's function return the
1016: computer value of the box you want checked. If the function returns a value
1017: that does not correspond to any of the choices, the default behavior of selecting
1018: the first choice will be preserved.
1019:
1020: For multichoice, return a string with the computer values you want checked,
1021: delimited by triple pipes. Note this matches how the result of the <choices>
1022: tag is stored in the {VARS} hash.
1023:
1024: =cut
1025:
1026: no strict;
1027: @ISA = ("Apache::lonhelper::element");
1028: use strict;
1029:
1030: BEGIN {
1031: &Apache::lonhelper::register('Apache::lonhelper::choices',
1032: ('choice', 'choices'));
1033: }
1034:
1035: sub new {
1036: my $ref = Apache::lonhelper::element->new();
1037: bless($ref);
1038: }
1039:
1040: # CONSTRUCTION: Construct the message element from the XML
1041: sub start_choices {
1042: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1043:
1044: if ($target ne 'helper') {
1045: return '';
1046: }
1047:
1048: # Need to initialize the choices list, so everything can assume it exists
1049: $paramHash->{'variable'} = $token->[2]{'variable'} if (!defined($paramHash->{'variable'}));
1050: $helper->declareVar($paramHash->{'variable'});
1051: $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
1052: $paramHash->{CHOICES} = [];
1053: return '';
1054: }
1055:
1056: sub end_choices {
1057: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1058:
1059: if ($target ne 'helper') {
1060: return '';
1061: }
1062: Apache::lonhelper::choices->new();
1063: return '';
1064: }
1065:
1066: sub start_choice {
1067: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1068:
1069: if ($target ne 'helper') {
1070: return '';
1071: }
1072:
1073: my $computer = $token->[2]{'computer'};
1074: my $human = &Apache::lonxml::get_all_text('/choice',
1075: $parser);
1076: my $nextstate = $token->[2]{'nextstate'};
1077: my $evalFlag = $token->[2]{'eval'};
1078: push @{$paramHash->{CHOICES}}, [$human, $computer, $nextstate,
1079: $evalFlag];
1080: return '';
1081: }
1082:
1083: sub end_choice {
1084: return '';
1085: }
1086:
1087: sub render {
1088: # START HERE: Replace this with correct choices code.
1089: my $self = shift;
1090: my $var = $self->{'variable'};
1091: my $buttons = '';
1092: my $result = '';
1093:
1094: if ($self->{'multichoice'}) {
1095: $result .= <<SCRIPT;
1096: <script>
1097: function checkall(value, checkName) {
1098: for (i=0; i<document.forms.helpform.elements.length; i++) {
1099: ele = document.forms.helpform.elements[i];
1100: if (ele.name == checkName + '.forminput') {
1101: document.forms.helpform.elements[i].checked=value;
1102: }
1103: }
1104: }
1105: </script>
1106: SCRIPT
1107: }
1108:
1109: # Only print "select all" and "unselect all" if there are five or
1110: # more choices; fewer then that and it looks silly.
1111: if ($self->{'multichoice'} && scalar(@{$self->{CHOICES}}) > 4) {
1112: $buttons = <<BUTTONS;
1113: <br />
1114: <input type="button" onclick="checkall(true, '$var')" value="Select All" />
1115: <input type="button" onclick="checkall(false, '$var')" value="Unselect All" />
1116: <br />
1117: BUTTONS
1118: }
1119:
1120: if (defined $self->{ERROR_MSG}) {
1121: $result .= '<br /><font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br />';
1122: }
1123:
1124: $result .= $buttons;
1125:
1126: $result .= "<table>\n\n";
1127:
1128: my %checkedChoices;
1129: my $checkedChoicesFunc;
1130:
1131: if (defined($self->{DEFAULT_VALUE})) {
1132: $checkedChoicesFunc = eval ($self->{DEFAULT_VALUE});
1133: die 'Error in default value code for variable ' .
1134: {'variable'} . ', Perl said:' . $@ if $@;
1135: } else {
1136: $checkedChoicesFunc = sub { return ''; };
1137: }
1138:
1139: # Process which choices should be checked.
1140: if ($self->{'multichoice'}) {
1141: for my $selectedChoice (split(/\|\|\|/, (&$checkedChoicesFunc($helper, $self)))) {
1142: $checkedChoices{$selectedChoice} = 1;
1143: }
1144: } else {
1145: # single choice
1146: my $selectedChoice = &$checkedChoicesFunc($helper, $self);
1147:
1148: my $foundChoice = 0;
1149:
1150: # check that the choice is in the list of choices.
1151: for my $choice (@{$self->{CHOICES}}) {
1152: if ($choice->[1] eq $selectedChoice) {
1153: $checkedChoices{$choice->[1]} = 1;
1154: $foundChoice = 1;
1155: }
1156: }
1157:
1158: # If we couldn't find the choice, pick the first one
1159: if (!$foundChoice) {
1160: $checkedChoices{$self->{CHOICES}->[0]->[1]} = 1;
1161: }
1162: }
1163:
1164: my $type = "radio";
1165: if ($self->{'multichoice'}) { $type = 'checkbox'; }
1166: foreach my $choice (@{$self->{CHOICES}}) {
1167: $result .= "<tr>\n<td width='20'> </td>\n";
1168: $result .= "<td valign='top'><input type='$type' name='$var.forminput'"
1169: . "' value='" .
1170: HTML::Entities::encode($choice->[1])
1171: . "'";
1172: if ($checkedChoices{$choice->[1]}) {
1173: $result .= " checked ";
1174: }
1175: my $choiceLabel = $choice->[0];
1176: if ($choice->[4]) { # if we need to evaluate this choice
1177: $choiceLabel = "sub { my $helper = shift; my $state = shift;" .
1178: $choiceLabel . "}";
1179: $choiceLabel = eval($choiceLabel);
1180: $choiceLabel = &$choiceLabel($helper, $self);
1181: }
1182: $result .= "/></td><td> " . $choiceLabel . "</td></tr>\n";
1183: }
1184: $result .= "</table>\n\n\n";
1185: $result .= $buttons;
1186:
1187: return $result;
1188: }
1189:
1190: # If a NEXTSTATE was given or a nextstate for this choice was
1191: # given, switch to it
1192: sub postprocess {
1193: my $self = shift;
1194: my $chosenValue = $ENV{'form.' . $self->{'variable'} . '.forminput'};
1195:
1196: if (!defined($chosenValue)) {
1197: $self->{ERROR_MSG} = "You must choose one or more choices to" .
1198: " continue.";
1199: return 0;
1200: }
1201:
1202: if ($self->{'multichoice'}) {
1203: $self->process_multiple_choices($self->{'variable'}.'.forminput',
1204: $self->{'variable'});
1205: }
1206:
1207: if (defined($self->{NEXTSTATE})) {
1208: $helper->changeState($self->{NEXTSTATE});
1209: }
1210:
1211: foreach my $choice (@{$self->{CHOICES}}) {
1212: if ($choice->[1] eq $chosenValue) {
1213: if (defined($choice->[2])) {
1214: $helper->changeState($choice->[2]);
1215: }
1216: }
1217: }
1218: return 1;
1219: }
1220: 1;
1221:
1222: package Apache::lonhelper::date;
1223:
1224: =pod
1225:
1226: =head2 Element: date
1227:
1228: Date elements allow the selection of a date with a drop down list.
1229:
1230: Date elements can take two attributes:
1231:
1232: =over 4
1233:
1234: =item * B<variable>: The name of the variable to store the chosen
1235: date in. Required.
1236:
1237: =item * B<hoursminutes>: If a true value, the date will show hours
1238: and minutes, as well as month/day/year. If false or missing,
1239: the date will only show the month, day, and year.
1240:
1241: =back
1242:
1243: Date elements contain only an option <nextstate> tag to determine
1244: the next state.
1245:
1246: Example:
1247:
1248: <date variable="DUE_DATE" hoursminutes="1">
1249: <nextstate>choose_why</nextstate>
1250: </date>
1251:
1252: =cut
1253:
1254: no strict;
1255: @ISA = ("Apache::lonhelper::element");
1256: use strict;
1257:
1258: use Time::localtime;
1259:
1260: BEGIN {
1261: &Apache::lonhelper::register('Apache::lonhelper::date',
1262: ('date'));
1263: }
1264:
1265: # Don't need to override the "new" from element
1266: sub new {
1267: my $ref = Apache::lonhelper::element->new();
1268: bless($ref);
1269: }
1270:
1271: my @months = ("January", "February", "March", "April", "May", "June", "July",
1272: "August", "September", "October", "November", "December");
1273:
1274: # CONSTRUCTION: Construct the message element from the XML
1275: sub start_date {
1276: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1277:
1278: if ($target ne 'helper') {
1279: return '';
1280: }
1281:
1282: $paramHash->{'variable'} = $token->[2]{'variable'};
1283: $helper->declareVar($paramHash->{'variable'});
1284: $paramHash->{'hoursminutes'} = $token->[2]{'hoursminutes'};
1285: }
1286:
1287: sub end_date {
1288: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1289:
1290: if ($target ne 'helper') {
1291: return '';
1292: }
1293: Apache::lonhelper::date->new();
1294: return '';
1295: }
1296:
1297: sub render {
1298: my $self = shift;
1299: my $result = "";
1300: my $var = $self->{'variable'};
1301:
1302: my $date;
1303:
1304: # Default date: The current hour.
1305: $date = localtime();
1306: $date->min(0);
1307:
1308: if (defined $self->{ERROR_MSG}) {
1309: $result .= '<font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
1310: }
1311:
1312: # Month
1313: my $i;
1314: $result .= "<select name='${var}month'>\n";
1315: for ($i = 0; $i < 12; $i++) {
1316: if ($i == $date->mon) {
1317: $result .= "<option value='$i' selected>";
1318: } else {
1319: $result .= "<option value='$i'>";
1320: }
1321: $result .= $months[$i] . "</option>\n";
1322: }
1323: $result .= "</select>\n";
1324:
1325: # Day
1326: $result .= "<select name='${var}day'>\n";
1327: for ($i = 1; $i < 32; $i++) {
1328: if ($i == $date->mday) {
1329: $result .= '<option selected>';
1330: } else {
1331: $result .= '<option>';
1332: }
1333: $result .= "$i</option>\n";
1334: }
1335: $result .= "</select>,\n";
1336:
1337: # Year
1338: $result .= "<select name='${var}year'>\n";
1339: for ($i = 2000; $i < 2030; $i++) { # update this after 64-bit dates
1340: if ($date->year + 1900 == $i) {
1341: $result .= "<option selected>";
1342: } else {
1343: $result .= "<option>";
1344: }
1345: $result .= "$i</option>\n";
1346: }
1347: $result .= "</select>,\n";
1348:
1349: # Display Hours and Minutes if they are called for
1350: if ($self->{'hoursminutes'}) {
1351: # Build hour
1352: $result .= "<select name='${var}hour'>\n";
1353: $result .= "<option " . ($date->hour == 0 ? 'selected ':'') .
1354: " value='0'>midnight</option>\n";
1355: for ($i = 1; $i < 12; $i++) {
1356: if ($date->hour == $i) {
1357: $result .= "<option selected value='$i'>$i a.m.</option>\n";
1358: } else {
1359: $result .= "<option value='$i'>$i a.m</option>\n";
1360: }
1361: }
1362: $result .= "<option " . ($date->hour == 12 ? 'selected ':'') .
1363: " value='12'>noon</option>\n";
1364: for ($i = 13; $i < 24; $i++) {
1365: my $printedHour = $i - 12;
1366: if ($date->hour == $i) {
1367: $result .= "<option selected value='$i'>$printedHour p.m.</option>\n";
1368: } else {
1369: $result .= "<option value='$i'>$printedHour p.m.</option>\n";
1370: }
1371: }
1372:
1373: $result .= "</select> :\n";
1374:
1375: $result .= "<select name='${var}minute'>\n";
1376: for ($i = 0; $i < 60; $i++) {
1377: my $printedMinute = $i;
1378: if ($i < 10) {
1379: $printedMinute = "0" . $printedMinute;
1380: }
1381: if ($date->min == $i) {
1382: $result .= "<option selected>";
1383: } else {
1384: $result .= "<option>";
1385: }
1386: $result .= "$printedMinute</option>\n";
1387: }
1388: $result .= "</select>\n";
1389: }
1390:
1391: return $result;
1392:
1393: }
1394: # If a NEXTSTATE was given, switch to it
1395: sub postprocess {
1396: my $self = shift;
1397: my $var = $self->{'variable'};
1398: my $month = $ENV{'form.' . $var . 'month'};
1399: my $day = $ENV{'form.' . $var . 'day'};
1400: my $year = $ENV{'form.' . $var . 'year'};
1401: my $min = 0;
1402: my $hour = 0;
1403: if ($self->{'hoursminutes'}) {
1404: $min = $ENV{'form.' . $var . 'minute'};
1405: $hour = $ENV{'form.' . $var . 'hour'};
1406: }
1407:
1408: my $chosenDate = Time::Local::timelocal(0, $min, $hour, $day, $month, $year);
1409: # Check to make sure that the date was not automatically co-erced into a
1410: # valid date, as we want to flag that as an error
1411: # This happens for "Feb. 31", for instance, which is coerced to March 2 or
1412: # 3, depending on if it's a leapyear
1413: my $checkDate = localtime($chosenDate);
1414:
1415: if ($checkDate->mon != $month || $checkDate->mday != $day ||
1416: $checkDate->year + 1900 != $year) {
1417: $self->{ERROR_MSG} = "Can't use " . $months[$month] . " $day, $year as a "
1418: . "date because it doesn't exist. Please enter a valid date.";
1419: return 0;
1420: }
1421:
1422: $helper->{VARS}->{$var} = $chosenDate;
1423:
1424: if (defined($self->{NEXTSTATE})) {
1425: $helper->changeState($self->{NEXTSTATE});
1426: }
1427:
1428: return 1;
1429: }
1430: 1;
1431:
1432: package Apache::lonhelper::resource;
1433:
1434: =pod
1435:
1436: =head2 Element: resource
1437:
1438: <resource> elements allow the user to select one or multiple resources
1439: from the current course. You can filter out which resources they can view,
1440: and filter out which resources they can select. The course will always
1441: be displayed fully expanded, because of the difficulty of maintaining
1442: selections across folder openings and closings. If this is fixed, then
1443: the user can manipulate the folders.
1444:
1445: <resource> takes the standard variable attribute to control what helper
1446: variable stores the results. It also takes a "multichoice" attribute,
1447: which controls whether the user can select more then one resource. The
1448: "toponly" attribute controls whether the resource display shows just the
1449: resources in that sequence, or recurses into all sub-sequences, defaulting
1450: to false.
1451:
1452: B<SUB-TAGS>
1453:
1454: =over 4
1455:
1456: =item * <filterfunc>: If you want to filter what resources are displayed
1457: to the user, use a filter func. The <filterfunc> tag should contain
1458: Perl code that when wrapped with "sub { my $res = shift; " and "}" is
1459: a function that returns true if the resource should be displayed,
1460: and false if it should be skipped. $res is a resource object.
1461: (See Apache::lonnavmaps documentation for information about the
1462: resource object.)
1463:
1464: =item * <choicefunc>: Same as <filterfunc>, except that controls whether
1465: the given resource can be chosen. (It is almost always a good idea to
1466: show the user the folders, for instance, but you do not always want to
1467: let the user select them.)
1468:
1469: =item * <nextstate>: Standard nextstate behavior.
1470:
1471: =item * <valuefunc>: This function controls what is returned by the resource
1472: when the user selects it. Like filterfunc and choicefunc, it should be
1473: a function fragment that when wrapped by "sub { my $res = shift; " and
1474: "}" returns a string representing what you want to have as the value. By
1475: default, the value will be the resource ID of the object ($res->{ID}).
1476:
1477: =item * <mapurl>: If the URL of a map is given here, only that map
1478: will be displayed, instead of the whole course.
1479:
1480: =back
1481:
1482: =cut
1483:
1484: no strict;
1485: @ISA = ("Apache::lonhelper::element");
1486: use strict;
1487:
1488: BEGIN {
1489: &Apache::lonhelper::register('Apache::lonhelper::resource',
1490: ('resource', 'filterfunc',
1491: 'choicefunc', 'valuefunc',
1492: 'mapurl'));
1493: }
1494:
1495: sub new {
1496: my $ref = Apache::lonhelper::element->new();
1497: bless($ref);
1498: }
1499:
1500: # CONSTRUCTION: Construct the message element from the XML
1501: sub start_resource {
1502: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1503:
1504: if ($target ne 'helper') {
1505: return '';
1506: }
1507:
1508: $paramHash->{'variable'} = $token->[2]{'variable'};
1509: $helper->declareVar($paramHash->{'variable'});
1510: $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
1511: $paramHash->{'toponly'} = $token->[2]{'toponly'};
1512: return '';
1513: }
1514:
1515: sub end_resource {
1516: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1517:
1518: if ($target ne 'helper') {
1519: return '';
1520: }
1521: if (!defined($paramHash->{FILTER_FUNC})) {
1522: $paramHash->{FILTER_FUNC} = sub {return 1;};
1523: }
1524: if (!defined($paramHash->{CHOICE_FUNC})) {
1525: $paramHash->{CHOICE_FUNC} = sub {return 1;};
1526: }
1527: if (!defined($paramHash->{VALUE_FUNC})) {
1528: $paramHash->{VALUE_FUNC} = sub {my $res = shift; return $res->{ID}; };
1529: }
1530: Apache::lonhelper::resource->new();
1531: return '';
1532: }
1533:
1534: sub start_filterfunc {
1535: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1536:
1537: if ($target ne 'helper') {
1538: return '';
1539: }
1540:
1541: my $contents = Apache::lonxml::get_all_text('/filterfunc',
1542: $parser);
1543: $contents = 'sub { my $res = shift; ' . $contents . '}';
1544: $paramHash->{FILTER_FUNC} = eval $contents;
1545: }
1546:
1547: sub end_filterfunc { return ''; }
1548:
1549: sub start_choicefunc {
1550: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1551:
1552: if ($target ne 'helper') {
1553: return '';
1554: }
1555:
1556: my $contents = Apache::lonxml::get_all_text('/choicefunc',
1557: $parser);
1558: $contents = 'sub { my $res = shift; ' . $contents . '}';
1559: $paramHash->{CHOICE_FUNC} = eval $contents;
1560: }
1561:
1562: sub end_choicefunc { return ''; }
1563:
1564: sub start_valuefunc {
1565: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1566:
1567: if ($target ne 'helper') {
1568: return '';
1569: }
1570:
1571: my $contents = Apache::lonxml::get_all_text('/valuefunc',
1572: $parser);
1573: $contents = 'sub { my $res = shift; ' . $contents . '}';
1574: $paramHash->{VALUE_FUNC} = eval $contents;
1575: }
1576:
1577: sub end_valuefunc { return ''; }
1578:
1579: sub start_mapurl {
1580: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1581:
1582: if ($target ne 'helper') {
1583: return '';
1584: }
1585:
1586: my $contents = Apache::lonxml::get_all_text('/mapurl',
1587: $parser);
1588: $paramHash->{MAP_URL} = $contents;
1589: }
1590:
1591: sub end_mapurl { return ''; }
1592:
1593: # A note, in case I don't get to this before I leave.
1594: # If someone complains about the "Back" button returning them
1595: # to the previous folder state, instead of returning them to
1596: # the previous helper state, the *correct* answer is for the helper
1597: # to keep track of how many times the user has manipulated the folders,
1598: # and feed that to the history.go() call in the helper rendering routines.
1599: # If done correctly, the helper itself can keep track of how many times
1600: # it renders the same states, so it doesn't go in just this state, and
1601: # you can lean on the browser back button to make sure it all chains
1602: # correctly.
1603: # Right now, though, I'm just forcing all folders open.
1604:
1605: sub render {
1606: my $self = shift;
1607: my $result = "";
1608: my $var = $self->{'variable'};
1609: my $curVal = $helper->{VARS}->{$var};
1610:
1611: my $buttons = '';
1612:
1613: if ($self->{'multichoice'}) {
1614: $result = <<SCRIPT;
1615: <script>
1616: function checkall(value, checkName) {
1617: for (i=0; i<document.forms.helpform.elements.length; i++) {
1618: ele = document.forms.helpform.elements[i];
1619: if (ele.name == checkName + '.forminput') {
1620: document.forms.helpform.elements[i].checked=value;
1621: }
1622: }
1623: }
1624: </script>
1625: SCRIPT
1626: $buttons = <<BUTTONS;
1627: <br />
1628: <input type="button" onclick="checkall(true, '$var')" value="Select All Resources" />
1629: <input type="button" onclick="checkall(false, '$var')" value="Unselect All Resources" />
1630: <br />
1631: BUTTONS
1632: }
1633:
1634: if (defined $self->{ERROR_MSG}) {
1635: $result .= '<br /><font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
1636: }
1637:
1638: $result .= $buttons;
1639:
1640: my $filterFunc = $self->{FILTER_FUNC};
1641: my $choiceFunc = $self->{CHOICE_FUNC};
1642: my $valueFunc = $self->{VALUE_FUNC};
1643: my $mapUrl = $self->{MAP_URL};
1644: my $multichoice = $self->{'multichoice'};
1645:
1646: # Create the composite function that renders the column on the nav map
1647: # have to admit any language that lets me do this can't be all bad
1648: # - Jeremy (Pythonista) ;-)
1649: my $checked = 0;
1650: my $renderColFunc = sub {
1651: my ($resource, $part, $params) = @_;
1652:
1653: my $inputType;
1654: if ($multichoice) { $inputType = 'checkbox'; }
1655: else {$inputType = 'radio'; }
1656:
1657: if (!&$choiceFunc($resource)) {
1658: return '<td> </td>';
1659: } else {
1660: my $col = "<td><input type='$inputType' name='${var}.forminput' ";
1661: if (!$checked && !$multichoice) {
1662: $col .= "checked ";
1663: $checked = 1;
1664: }
1665: $col .= "value='" .
1666: HTML::Entities::encode(&$valueFunc($resource))
1667: . "' /></td>";
1668: return $col;
1669: }
1670: };
1671:
1672: $ENV{'form.condition'} = !$self->{'toponly'};
1673: $result .=
1674: &Apache::lonnavmaps::render( { 'cols' => [$renderColFunc,
1675: Apache::lonnavmaps::resource()],
1676: 'showParts' => 0,
1677: 'filterFunc' => $filterFunc,
1678: 'resource_no_folder_link' => 1,
1679: 'iterator_map' => $mapUrl }
1680: );
1681:
1682: $result .= $buttons;
1683:
1684: return $result;
1685: }
1686:
1687: sub postprocess {
1688: my $self = shift;
1689:
1690: if ($self->{'multichoice'}) {
1691: $self->process_multiple_choices($self->{'variable'}.'.forminput',
1692: $self->{'variable'});
1693: }
1694:
1695: if ($self->{'multichoice'} && !$helper->{VARS}->{$self->{'variable'}}) {
1696: $self->{ERROR_MSG} = 'You must choose at least one resource to continue.';
1697: return 0;
1698: }
1699:
1700: if (defined($self->{NEXTSTATE})) {
1701: $helper->changeState($self->{NEXTSTATE});
1702: }
1703:
1704: return 1;
1705: }
1706:
1707: 1;
1708:
1709: package Apache::lonhelper::student;
1710:
1711: =pod
1712:
1713: =head2 Element: student
1714:
1715: Student elements display a choice of students enrolled in the current
1716: course. Currently it is primitive; this is expected to evolve later.
1717:
1718: Student elements take two attributes: "variable", which means what
1719: it usually does, and "multichoice", which if true allows the user
1720: to select multiple students.
1721:
1722: =cut
1723:
1724: no strict;
1725: @ISA = ("Apache::lonhelper::element");
1726: use strict;
1727:
1728:
1729:
1730: BEGIN {
1731: &Apache::lonhelper::register('Apache::lonhelper::student',
1732: ('student'));
1733: }
1734:
1735: sub new {
1736: my $ref = Apache::lonhelper::element->new();
1737: bless($ref);
1738: }
1739:
1740: sub start_student {
1741: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1742:
1743: if ($target ne 'helper') {
1744: return '';
1745: }
1746:
1747: $paramHash->{'variable'} = $token->[2]{'variable'};
1748: $helper->declareVar($paramHash->{'variable'});
1749: $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
1750: if (defined($token->[2]{'nextstate'})) {
1751: $paramHash->{NEXTSTATE} = $token->[2]{'nextstate'};
1752: }
1753:
1754: }
1755:
1756: sub end_student {
1757: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1758:
1759: if ($target ne 'helper') {
1760: return '';
1761: }
1762: Apache::lonhelper::student->new();
1763: }
1764:
1765: sub render {
1766: my $self = shift;
1767: my $result = '';
1768: my $buttons = '';
1769: my $var = $self->{'variable'};
1770:
1771: if ($self->{'multichoice'}) {
1772: $result = <<SCRIPT;
1773: <script>
1774: function checkall(value, checkName) {
1775: for (i=0; i<document.forms.helpform.elements.length; i++) {
1776: ele = document.forms.helpform.elements[i];
1777: if (ele.name == checkName + '.forminput') {
1778: document.forms.helpform.elements[i].checked=value;
1779: }
1780: }
1781: }
1782: </script>
1783: SCRIPT
1784: $buttons = <<BUTTONS;
1785: <br />
1786: <input type="button" onclick="checkall(true, '$var')" value="Select All Students" />
1787: <input type="button" onclick="checkall(false, '$var')" value="Unselect All Students" />
1788: <br />
1789: BUTTONS
1790: }
1791:
1792: if (defined $self->{ERROR_MSG}) {
1793: $result .= '<font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
1794: }
1795:
1796: # Load up the students
1797: my $choices = &Apache::loncoursedata::get_classlist();
1798: my @keys = keys %{$choices};
1799:
1800: # Constants
1801: my $section = Apache::loncoursedata::CL_SECTION();
1802: my $fullname = Apache::loncoursedata::CL_FULLNAME();
1803:
1804: # Sort by: Section, name
1805: @keys = sort {
1806: if ($choices->{$a}->[$section] ne $choices->{$b}->[$section]) {
1807: return $choices->{$a}->[$section] cmp $choices->{$b}->[$section];
1808: }
1809: return $choices->{$a}->[$fullname] cmp $choices->{$b}->[$fullname];
1810: } @keys;
1811:
1812: my $type = 'radio';
1813: if ($self->{'multichoice'}) { $type = 'checkbox'; }
1814: $result .= "<table cellspacing='2' cellpadding='2' border='0'>\n";
1815: $result .= "<tr><td></td><td align='center'><b>Student Name</b></td>".
1816: "<td align='center'><b>Section</b></td></tr>";
1817:
1818: my $checked = 0;
1819: foreach (@keys) {
1820: $result .= "<tr><td><input type='$type' name='" .
1821: $self->{'variable'} . '.forminput' . "'";
1822:
1823: if (!$self->{'multichoice'} && !$checked) {
1824: $result .= " checked ";
1825: $checked = 1;
1826: }
1827: $result .=
1828: " value='" . HTML::Entities::encode($_ . ':' . $choices->{$_}->[$section])
1829: . "' /></td><td>"
1830: . HTML::Entities::encode($choices->{$_}->[$fullname])
1831: . "</td><td align='center'>"
1832: . HTML::Entities::encode($choices->{$_}->[$section])
1833: . "</td></tr>\n";
1834: }
1835:
1836: $result .= "</table>\n\n";
1837: $result .= $buttons;
1838:
1839: return $result;
1840: }
1841:
1842: sub postprocess {
1843: my $self = shift;
1844:
1845: my $result = $ENV{'form.' . $self->{'variable'} . '.forminput'};
1846: if (!$result) {
1847: $self->{ERROR_MSG} = 'You must choose at least one student '.
1848: 'to continue.';
1849: return 0;
1850: }
1851:
1852: if ($self->{'multichoice'}) {
1853: $self->process_multiple_choices($self->{'variable'}.'.forminput',
1854: $self->{'variable'});
1855: }
1856: if (defined($self->{NEXTSTATE})) {
1857: $helper->changeState($self->{NEXTSTATE});
1858: }
1859:
1860: return 1;
1861: }
1862:
1863: 1;
1864:
1865: package Apache::lonhelper::files;
1866:
1867: =pod
1868:
1869: =head2 Element: files
1870:
1871: files allows the users to choose files from a given directory on the
1872: server. It is always multichoice and stores the result as a triple-pipe
1873: delimited entry in the helper variables.
1874:
1875: Since it is extremely unlikely that you can actually code a constant
1876: representing the directory you wish to allow the user to search, <files>
1877: takes a subroutine that returns the name of the directory you wish to
1878: have the user browse.
1879:
1880: files accepts the attribute "variable" to control where the files chosen
1881: are put. It accepts the attribute "multichoice" as the other attribute,
1882: defaulting to false, which if true will allow the user to select more
1883: then one choice.
1884:
1885: <files> accepts three subtags. One is the "nextstate" sub-tag that works
1886: as it does with the other tags. Another is a <filechoice> sub tag that
1887: is Perl code that, when surrounded by "sub {" and "}" will return a
1888: string representing what directory on the server to allow the user to
1889: choose files from. Finally, the <filefilter> subtag should contain Perl
1890: code that when surrounded by "sub { my $filename = shift; " and "}",
1891: returns a true value if the user can pick that file, or false otherwise.
1892: The filename passed to the function will be just the name of the file,
1893: with no path info.
1894:
1895: =cut
1896:
1897: no strict;
1898: @ISA = ("Apache::lonhelper::element");
1899: use strict;
1900:
1901: BEGIN {
1902: &Apache::lonhelper::register('Apache::lonhelper::files',
1903: ('files', 'filechoice', 'filefilter'));
1904: }
1905:
1906: sub new {
1907: my $ref = Apache::lonhelper::element->new();
1908: bless($ref);
1909: }
1910:
1911: sub start_files {
1912: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1913:
1914: if ($target ne 'helper') {
1915: return '';
1916: }
1917: $paramHash->{'variable'} = $token->[2]{'variable'};
1918: $helper->declareVar($paramHash->{'variable'});
1919: $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
1920: }
1921:
1922: sub end_files {
1923: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1924:
1925: if ($target ne 'helper') {
1926: return '';
1927: }
1928: if (!defined($paramHash->{FILTER_FUNC})) {
1929: $paramHash->{FILTER_FUNC} = sub { return 1; };
1930: }
1931: Apache::lonhelper::files->new();
1932: }
1933:
1934: sub start_filechoice {
1935: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1936:
1937: if ($target ne 'helper') {
1938: return '';
1939: }
1940: $paramHash->{'filechoice'} = Apache::lonxml::get_all_text('/filechoice',
1941: $parser);
1942: }
1943:
1944: sub end_filechoice { return ''; }
1945:
1946: sub start_filefilter {
1947: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
1948:
1949: if ($target ne 'helper') {
1950: return '';
1951: }
1952:
1953: my $contents = Apache::lonxml::get_all_text('/filefilter',
1954: $parser);
1955: $contents = 'sub { my $filename = shift; ' . $contents . '}';
1956: $paramHash->{FILTER_FUNC} = eval $contents;
1957: }
1958:
1959: sub end_filefilter { return ''; }
1960:
1961: sub render {
1962: my $self = shift;
1963: my $result = '';
1964: my $var = $self->{'variable'};
1965:
1966: my $subdirFunc = eval('sub {' . $self->{'filechoice'} . '}');
1967: die 'Error in resource filter code for variable ' .
1968: {'variable'} . ', Perl said:' . $@ if $@;
1969:
1970: my $subdir = &$subdirFunc();
1971:
1972: my $filterFunc = $self->{FILTER_FUNC};
1973: my $buttons = '';
1974: my $type = 'radio';
1975: if ($self->{'multichoice'}) {
1976: $type = 'checkbox';
1977: }
1978:
1979: if ($self->{'multichoice'}) {
1980: $result = <<SCRIPT;
1981: <script>
1982: function checkall(value, checkName) {
1983: for (i=0; i<document.forms.helpform.elements.length; i++) {
1984: ele = document.forms.helpform.elements[i];
1985: if (ele.name == checkName + '.forminput') {
1986: document.forms.helpform.elements[i].checked=value;
1987: }
1988: }
1989: }
1990:
1991: function checkallclass(value, className) {
1992: for (i=0; i<document.forms.helpform.elements.length; i++) {
1993: ele = document.forms.helpform.elements[i];
1994: if (ele.type == "$type" && ele.onclick) {
1995: document.forms.helpform.elements[i].checked=value;
1996: }
1997: }
1998: }
1999: </script>
2000: SCRIPT
2001: $buttons = <<BUTTONS;
2002: <br />
2003: <input type="button" onclick="checkall(true, '$var')" value="Select All Files" />
2004: <input type="button" onclick="checkall(false, '$var')" value="Unselect All Files" />
2005: BUTTONS
2006:
2007: if ($helper->{VARS}->{'construction'}) {
2008: $buttons .= <<BUTTONS;
2009: <input type="button" onclick="checkallclass(true, 'Published')" value="Select All Published" />
2010: <input type="button" onclick="checkallclass(false, 'Published')" value="Unselect All Published" />
2011: <br />
2012: BUTTONS
2013: }
2014: }
2015:
2016: # Get the list of files in this directory.
2017: my @fileList;
2018:
2019: # If the subdirectory is in local CSTR space
2020: if ($subdir =~ m|/home/([^/]+)/public_html|) {
2021: my $user = $1;
2022: my $domain = $Apache::lonnet::perlvar{'lonDefDomain'};
2023: @fileList = &Apache::lonnet::dirlist($subdir, $domain, $user, '');
2024: } else {
2025: # local library server resource space
2026: @fileList = &Apache::lonnet::dirlist($subdir, $ENV{'user.domain'}, $ENV{'user.name'}, '');
2027: }
2028:
2029: $result .= $buttons;
2030:
2031: if (defined $self->{ERROR_MSG}) {
2032: $result .= '<br /><font color="#FF0000">' . $self->{ERROR_MSG} . '</font><br /><br />';
2033: }
2034:
2035: $result .= '<table border="0" cellpadding="2" cellspacing="0">';
2036:
2037: # Keeps track if there are no choices, prints appropriate error
2038: # if there are none.
2039: my $choices = 0;
2040: # Print each legitimate file choice.
2041: for my $file (@fileList) {
2042: $file = (split(/&/, $file))[0];
2043: if ($file eq '.' || $file eq '..') {
2044: next;
2045: }
2046: my $fileName = $subdir .'/'. $file;
2047: if (&$filterFunc($file)) {
2048: my $status;
2049: my $color;
2050: if ($helper->{VARS}->{'construction'}) {
2051: ($status, $color) = @{fileState($subdir, $file)};
2052: } else {
2053: $status = '';
2054: $color = '';
2055: }
2056:
2057: # Netscape 4 is stupid and there's nowhere to put the
2058: # information on the input tag that the file is Published,
2059: # Unpublished, etc. In *real* browsers we can just say
2060: # "class='Published'" and check the className attribute of
2061: # the input tag, but Netscape 4 is too stupid to understand
2062: # that attribute, and un-comprehended attributes are not
2063: # reflected into the object model. So instead, what I do
2064: # is either have or don't have an "onclick" handler that
2065: # does nothing, give Published files the onclick handler, and
2066: # have the checker scripts check for that. Stupid and clumsy,
2067: # and only gives us binary "yes/no" information (at least I
2068: # couldn't figure out how to reach into the event handler's
2069: # actual code to retreive a value), but it works well enough
2070: # here.
2071:
2072: my $onclick = '';
2073: if ($status eq 'Published' && $helper->{VARS}->{'construction'}) {
2074: $onclick = 'onclick="a=1" ';
2075: }
2076: $result .= '<tr><td align="right"' . " bgcolor='$color'>" .
2077: "<input $onclick type='$type' name='" . $var
2078: . ".forminput' value='" . HTML::Entities::encode($fileName) .
2079: "'";
2080: if (!$self->{'multichoice'} && $choices == 0) {
2081: $result .= ' checked';
2082: }
2083: $result .= "/></td><td bgcolor='$color'>" . $file .
2084: "</td><td bgcolor='$color'>$status</td></tr>\n";
2085: $choices++;
2086: }
2087: }
2088:
2089: $result .= "</table>\n";
2090:
2091: if (!$choices) {
2092: $result .= '<font color="#FF0000">There are no files available to select in this directory. Please go back and select another option.</font><br /><br />';
2093: }
2094:
2095: $result .= $buttons;
2096:
2097: return $result;
2098: }
2099:
2100: # Determine the state of the file: Published, unpublished, modified.
2101: # Return the color it should be in and a label as a two-element array
2102: # reference.
2103: # Logic lifted from lonpubdir.pm, even though I don't know that it's still
2104: # the most right thing to do.
2105:
2106: sub fileState {
2107: my $constructionSpaceDir = shift;
2108: my $file = shift;
2109:
2110: my $docroot = $Apache::lonnet::perlvar{'lonDocRoot'};
2111: my $subdirpart = $constructionSpaceDir;
2112: $subdirpart =~ s/^\/home\/$ENV{'user.name'}\/public_html//;
2113: my $resdir = $docroot . '/res/' . $ENV{'user.domain'} . '/' . $ENV{'user.name'} .
2114: $subdirpart;
2115:
2116: my @constructionSpaceFileStat = stat($constructionSpaceDir . '/' . $file);
2117: my @resourceSpaceFileStat = stat($resdir . '/' . $file);
2118: if (!@resourceSpaceFileStat) {
2119: return ['Unpublished', '#FFCCCC'];
2120: }
2121:
2122: my $constructionSpaceFileModified = $constructionSpaceFileStat[9];
2123: my $resourceSpaceFileModified = $resourceSpaceFileStat[9];
2124:
2125: if ($constructionSpaceFileModified > $resourceSpaceFileModified) {
2126: return ['Modified', '#FFFFCC'];
2127: }
2128: return ['Published', '#CCFFCC'];
2129: }
2130:
2131: sub postprocess {
2132: my $self = shift;
2133: my $result = $ENV{'form.' . $self->{'variable'} . '.forminput'};
2134: if (!$result) {
2135: $self->{ERROR_MSG} = 'You must choose at least one file '.
2136: 'to continue.';
2137: return 0;
2138: }
2139:
2140: if ($self->{'multichoice'}) {
2141: $self->process_multiple_choices($self->{'variable'}.'.forminput',
2142: $self->{'variable'});
2143: }
2144: if (defined($self->{NEXTSTATE})) {
2145: $helper->changeState($self->{NEXTSTATE});
2146: }
2147:
2148: return 1;
2149: }
2150:
2151: 1;
2152:
2153: package Apache::lonhelper::section;
2154:
2155: =pod
2156:
2157: =head2 Element: section
2158:
2159: <section> allows the user to choose one or more sections from the current
2160: course.
2161:
2162: It takes the standard attributes "variable", "multichoice", and
2163: "nextstate", meaning what they do for most other elements.
2164:
2165: =cut
2166:
2167: no strict;
2168: @ISA = ("Apache::lonhelper::choices");
2169: use strict;
2170:
2171: BEGIN {
2172: &Apache::lonhelper::register('Apache::lonhelper::section',
2173: ('section'));
2174: }
2175:
2176: sub new {
2177: my $ref = Apache::lonhelper::choices->new();
2178: bless($ref);
2179: }
2180:
2181: sub start_section {
2182: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
2183:
2184: if ($target ne 'helper') {
2185: return '';
2186: }
2187:
2188: $paramHash->{CHOICES} = [];
2189:
2190: $paramHash->{'variable'} = $token->[2]{'variable'};
2191: $helper->declareVar($paramHash->{'variable'});
2192: $paramHash->{'multichoice'} = $token->[2]{'multichoice'};
2193: if (defined($token->[2]{'nextstate'})) {
2194: $paramHash->{NEXTSTATE} = $token->[2]{'nextstate'};
2195: }
2196:
2197: # Populate the CHOICES element
2198: my %choices;
2199:
2200: my $section = Apache::loncoursedata::CL_SECTION();
2201: my $classlist = Apache::loncoursedata::get_classlist();
2202: foreach (keys %$classlist) {
2203: my $sectionName = $classlist->{$_}->[$section];
2204: if (!$sectionName) {
2205: $choices{"No section assigned"} = "";
2206: } else {
2207: $choices{$sectionName} = $sectionName;
2208: }
2209: }
2210:
2211: for my $sectionName (sort(keys(%choices))) {
2212:
2213: push @{$paramHash->{CHOICES}}, [$sectionName, $sectionName];
2214: }
2215: }
2216:
2217: sub end_section {
2218: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
2219:
2220: if ($target ne 'helper') {
2221: return '';
2222: }
2223: Apache::lonhelper::section->new();
2224: }
2225: 1;
2226:
2227: package Apache::lonhelper::general;
2228:
2229: =pod
2230:
2231: =head2 General-purpose tag: <exec>
2232:
2233: The contents of the exec tag are executed as Perl code, not inside a
2234: safe space, so the full range of $ENV and such is available. The code
2235: will be executed as a subroutine wrapped with the following code:
2236:
2237: "sub { my $helper = shift; my $state = shift;" and
2238:
2239: "}"
2240:
2241: The return value is ignored.
2242:
2243: $helper is the helper object. Feel free to add methods to the helper
2244: object to support whatever manipulation you may need to do (for instance,
2245: overriding the form location if the state is the final state; see
2246: lonparm.helper for an example).
2247:
2248: $state is the $paramHash that has currently been generated and may
2249: be manipulated by the code in exec. Note that the $state is not yet
2250: an actual state B<object>, it is just a hash, so do not expect to
2251: be able to call methods on it.
2252:
2253: =cut
2254:
2255: BEGIN {
2256: &Apache::lonhelper::register('Apache::lonhelper::general',
2257: 'exec', 'condition', 'clause',
2258: 'eval');
2259: }
2260:
2261: sub start_exec {
2262: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
2263:
2264: if ($target ne 'helper') {
2265: return '';
2266: }
2267:
2268: my $code = &Apache::lonxml::get_all_text('/exec', $parser);
2269:
2270: $code = eval ('sub { my $helper = shift; my $state = shift; ' .
2271: $code . "}");
2272: die 'Error in <exec>, Perl said: '. $@ if $@;
2273: &$code($helper, $paramHash);
2274: }
2275:
2276: sub end_exec { return ''; }
2277:
2278: =pod
2279:
2280: =head2 General-purpose tag: <condition>
2281:
2282: The <condition> tag allows you to mask out parts of the helper code
2283: depending on some programatically determined condition. The condition
2284: tag contains a tag <clause> which contains perl code that when wrapped
2285: with "sub { my $helper = shift; my $state = shift; " and "}", returns
2286: a true value if the XML in the condition should be evaluated as a normal
2287: part of the helper, or false if it should be completely discarded.
2288:
2289: The <clause> tag must be the first sub-tag of the <condition> tag or
2290: it will not work as expected.
2291:
2292: =cut
2293:
2294: # The condition tag just functions as a marker, it doesn't have
2295: # to "do" anything. Technically it doesn't even have to be registered
2296: # with the lonxml code, but I leave this here to be explicit about it.
2297: sub start_condition { return ''; }
2298: sub end_condition { return ''; }
2299:
2300: sub start_clause {
2301: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
2302:
2303: if ($target ne 'helper') {
2304: return '';
2305: }
2306:
2307: my $clause = Apache::lonxml::get_all_text('/clause', $parser);
2308: $clause = eval('sub { my $helper = shift; my $state = shift; '
2309: . $clause . '}');
2310: die 'Error in clause of condition, Perl said: ' . $@ if $@;
2311: if (!&$clause($helper, $paramHash)) {
2312: # Discard all text until the /condition.
2313: &Apache::lonxml::get_all_text('/condition', $parser);
2314: }
2315: }
2316:
2317: sub end_clause { return ''; }
2318:
2319: =pod
2320:
2321: =head2 General-purpose tag: <eval>
2322:
2323: The <eval> tag will be evaluated as a subroutine call passed in the
2324: current helper object and state hash as described in <condition> above,
2325: but is expected to return a string to be printed directly to the
2326: screen. This is useful for dynamically generating messages.
2327:
2328: =cut
2329:
2330: # This is basically a type of message.
2331: # Programmatically setting $paramHash->{NEXTSTATE} would work, though
2332: # it's probably bad form.
2333:
2334: sub start_eval {
2335: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
2336:
2337: if ($target ne 'helper') {
2338: return '';
2339: }
2340:
2341: my $program = Apache::lonxml::get_all_text('/eval', $parser);
2342: $program = eval('sub { my $helper = shift; my $state = shift; '
2343: . $program . '}');
2344: die 'Error in eval code, Perl said: ' . $@ if $@;
2345: $paramHash->{MESSAGE_TEXT} = &$program($helper, $paramHash);
2346: }
2347:
2348: sub end_eval {
2349: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
2350:
2351: if ($target ne 'helper') {
2352: return '';
2353: }
2354:
2355: Apache::lonhelper::message->new();
2356: }
2357:
2358: 1;
2359:
2360: package Apache::lonhelper::parmwizfinal;
2361:
2362: # This is the final state for the parmwizard. It is not generally useful,
2363: # so it is not perldoc'ed. It does its own processing.
2364: # It is represented with <parmwizfinal />, and
2365: # should later be moved to lonparmset.pm .
2366:
2367: no strict;
2368: @ISA = ('Apache::lonhelper::element');
2369: use strict;
2370:
2371: BEGIN {
2372: &Apache::lonhelper::register('Apache::lonhelper::parmwizfinal',
2373: ('parmwizfinal'));
2374: }
2375:
2376: use Time::localtime;
2377:
2378: sub new {
2379: my $ref = Apache::lonhelper::choices->new();
2380: bless ($ref);
2381: }
2382:
2383: sub start_parmwizfinal { return ''; }
2384:
2385: sub end_parmwizfinal {
2386: my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
2387:
2388: if ($target ne 'helper') {
2389: return '';
2390: }
2391: Apache::lonhelper::parmwizfinal->new();
2392: }
2393:
2394: # Renders a form that, when submitted, will form the input to lonparmset.pm
2395: sub render {
2396: my $self = shift;
2397: my $vars = $helper->{VARS};
2398:
2399: # FIXME: Unify my designators with the standard ones
2400: my %dateTypeHash = ('open_date' => "Opening Date",
2401: 'due_date' => "Due Date",
2402: 'answer_date' => "Answer Date");
2403: my %parmTypeHash = ('open_date' => "0_opendate",
2404: 'due_date' => "0_duedate",
2405: 'answer_date' => "0_answerdate");
2406:
2407: my $result = "<form name='helpform' method='get' action='/adm/parmset'>\n";
2408: $result .= '<p>Confirm that this information is correct, then click "Finish Wizard" to complete setting the parameter.<ul>';
2409: my $affectedResourceId = "";
2410: my $parm_name = $parmTypeHash{$vars->{ACTION_TYPE}};
2411: my $level = "";
2412:
2413: # Print the type of manipulation:
2414: $result .= '<li>Setting the <b>' . $dateTypeHash{$vars->{ACTION_TYPE}}
2415: . "</b></li>\n";
2416: if ($vars->{ACTION_TYPE} eq 'due_date' ||
2417: $vars->{ACTION_TYPE} eq 'answer_date') {
2418: # for due dates, we default to "date end" type entries
2419: $result .= "<input type='hidden' name='recent_date_end' " .
2420: "value='" . $vars->{PARM_DATE} . "' />\n";
2421: $result .= "<input type='hidden' name='pres_value' " .
2422: "value='" . $vars->{PARM_DATE} . "' />\n";
2423: $result .= "<input type='hidden' name='pres_type' " .
2424: "value='date_end' />\n";
2425: } elsif ($vars->{ACTION_TYPE} eq 'open_date') {
2426: $result .= "<input type='hidden' name='recent_date_start' ".
2427: "value='" . $vars->{PARM_DATE} . "' />\n";
2428: $result .= "<input type='hidden' name='pres_value' " .
2429: "value='" . $vars->{PARM_DATE} . "' />\n";
2430: $result .= "<input type='hidden' name='pres_type' " .
2431: "value='date_start' />\n";
2432: }
2433:
2434: # Print the granularity, depending on the action
2435: if ($vars->{GRANULARITY} eq 'whole_course') {
2436: $result .= '<li>for <b>all resources in the course</b></li>';
2437: $level = 9; # general course, see lonparmset.pm perldoc
2438: $affectedResourceId = "0.0";
2439: } elsif ($vars->{GRANULARITY} eq 'map') {
2440: my $navmap = Apache::lonnavmaps::navmap->new(
2441: $ENV{"request.course.fn"}.".db",
2442: $ENV{"request.course.fn"}."_parms.db", 0, 0);
2443: my $res = $navmap->getById($vars->{RESOURCE_ID});
2444: my $title = $res->compTitle();
2445: $navmap->untieHashes();
2446: $result .= "<li>for the map named <b>$title</b></li>";
2447: $level = 8;
2448: $affectedResourceId = $vars->{RESOURCE_ID};
2449: } else {
2450: my $navmap = Apache::lonnavmaps::navmap->new(
2451: $ENV{"request.course.fn"}.".db",
2452: $ENV{"request.course.fn"}."_parms.db", 0, 0);
2453: my $res = $navmap->getById($vars->{RESOURCE_ID});
2454: my $title = $res->compTitle();
2455: $navmap->untieHashes();
2456: $result .= "<li>for the resource named <b>$title</b></li>";
2457: $level = 7;
2458: $affectedResourceId = $vars->{RESOURCE_ID};
2459: }
2460:
2461: # Print targets
2462: if ($vars->{TARGETS} eq 'course') {
2463: $result .= '<li>for <b>all students in course</b></li>';
2464: } elsif ($vars->{TARGETS} eq 'section') {
2465: my $section = $vars->{SECTION_NAME};
2466: $result .= "<li>for section <b>$section</b></li>";
2467: $level -= 3;
2468: $result .= "<input type='hidden' name='csec' value='" .
2469: HTML::Entities::encode($section) . "' />\n";
2470: } else {
2471: # FIXME: This is probably wasteful! Store the name!
2472: my $classlist = Apache::loncoursedata::get_classlist();
2473: my $name = $classlist->{$vars->{USER_NAME}}->[6];
2474: $result .= "<li>for <b>$name</b></li>";
2475: $level -= 6;
2476: my ($uname, $udom) = split /:/, $vars->{USER_NAME};
2477: $result .= "<input type='hidden' name='uname' value='".
2478: HTML::Entities::encode($uname) . "' />\n";
2479: $result .= "<input type='hidden' name='udom' value='".
2480: HTML::Entities::encode($udom) . "' />\n";
2481: }
2482:
2483: # Print value
2484: $result .= "<li>to <b>" . ctime($vars->{PARM_DATE}) . "</b> (" .
2485: Apache::lonnavmaps::timeToHumanString($vars->{PARM_DATE})
2486: . ")</li>\n";
2487:
2488: # print pres_marker
2489: $result .= "\n<input type='hidden' name='pres_marker'" .
2490: " value='$affectedResourceId&$parm_name&$level' />\n";
2491:
2492: $result .= "<br /><br /><center><input type='submit' value='Finish Helper' /></center></form>\n";
2493:
2494: return $result;
2495: }
2496:
2497: sub overrideForm {
2498: return 1;
2499: }
2500:
2501: 1;
2502:
2503: __END__
2504:
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