Return to lonhomework.pm CVS log

Up to [LON-CAPA] / loncom / homework

- Fixes BUG#794
- Created new status UNAVAILABLE
- EXT now passes con_lost and no_such_host messages back when fetching parameters
- Updated start_problem, start_part, and gradestatus to understand new UNAVAILABLE status

    1: # The LearningOnline Network with CAPA
    2: # The LON-CAPA Homework handler
    3: #
    4: # $Id: lonhomework.pm,v 1.103 2002/12/05 22:59:37 albertel 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: # Guy Albertelli
   29: # 11/30 Gerd Kortemeyer
   30: # 6/1,8/17,8/18 Gerd Kortemeyer
   31: # 7/18 Jeremy Bowers
   32: 
   33: package Apache::lonhomework;
   34: use strict;
   35: use Apache::style();
   36: use Apache::lonxml();
   37: use Apache::lonnet();
   38: use Apache::lonplot();
   39: use Apache::inputtags();
   40: use Apache::structuretags();
   41: use Apache::randomlabel();
   42: use Apache::response();
   43: use Apache::hint();
   44: use Apache::outputtags();
   45: use Apache::caparesponse();
   46: use Apache::radiobuttonresponse();
   47: use Apache::optionresponse();
   48: use Apache::imageresponse();
   49: use Apache::essayresponse();
   50: use Apache::externalresponse();
   51: use Apache::Constants qw(:common);
   52: use HTML::Entities();
   53: use Apache::loncommon();
   54: #use Time::HiRes qw( gettimeofday tv_interval );
   55: 
   56: BEGIN {
   57:   &Apache::lonxml::register_insert();
   58: }
   59: 
   60: sub get_target {
   61:   if ( $ENV{'request.state'} eq "published") {
   62:     if ( defined($ENV{'form.grade_target'}  ) 
   63: 	 && ($ENV{'form.grade_target'} eq 'tex')) {
   64:       return ($ENV{'form.grade_target'});
   65:     } elsif ( defined($ENV{'form.grade_target'}  ) 
   66: 	 && ($Apache::lonhomework::viewgrades == 'F' )) {
   67:       return ($ENV{'form.grade_target'});
   68:     }
   69:  
   70:     if ( defined($ENV{'form.submitted'})) {
   71:       return ('grade', 'web');
   72:     } else {
   73:       return ('web');
   74:     }
   75:   } elsif ($ENV{'request.state'} eq "construct") {
   76:     if ( defined($ENV{'form.grade_target'}) ) {
   77:       return ($ENV{'form.grade_target'});
   78:     }
   79:     if ( defined($ENV{'form.preview'})) {
   80:       if ( defined($ENV{'form.submitted'})) {
   81: 	return ('grade', 'web');
   82:       } else {
   83: 	return ('web');
   84:       }
   85:     } else {
   86:       if ( $ENV{'form.problemmode'} eq 'View' ||
   87: 	   $ENV{'form.problemmode'} eq 'Discard Edits and View') {
   88: 	if ( defined($ENV{'form.submitted'}) &&
   89: 	     (!defined($ENV{'form.resetdata'})) ) {
   90: 	  return ('grade', 'web','answer');
   91: 	} else {
   92: 	  return ('web','answer');
   93: 	}
   94:       } elsif ( $ENV{'form.problemmode'} eq 'Edit' ) {
   95: 	if ( $ENV{'form.submitted'} eq 'edit' ) {
   96: 	  if ( $ENV{'form.submit'} eq 'Submit Changes and View' ) {
   97: 	    return ('modified','web','answer');
   98: 	  } else {
   99: 	    return ('modified','edit');
  100: 	  }
  101: 	} else {
  102: 	  return ('edit');
  103: 	}
  104:       } else {
  105: 	return ('web');
  106:       }
  107:     }
  108:   }
  109:   return ();
  110: }
  111: 
  112: sub setup_vars {
  113:   my ($target) = @_;
  114:   return ';'
  115: #  return ';$external::target='.$target.';';
  116: }
  117: 
  118: sub send_header {
  119:   my ($request)= @_;
  120:   $request->print(&Apache::lontexconvert::header());
  121: #  $request->print('<form name='.$ENV{'form.request.prefix'}.'lonhomework method="POST" action="'.$request->uri.'">');
  122: }
  123: 
  124: sub createmenu {
  125:   my ($which,$request)=@_;
  126:   if ($which eq 'grade') {
  127:     $request->print('<script language="JavaScript"> 
  128:           hwkmenu=window.open("/res/adm/pages/homeworkmenu.html","homeworkremote",
  129:                  "height=350,width=150,menubar=no");
  130:           </script>');
  131:   }
  132: }
  133: 
  134: sub send_footer {
  135:   my ($request)= @_;
  136: #  $request->print('</form>');
  137:   $request->print(&Apache::lontexconvert::footer());
  138: }
  139: 
  140: $Apache::lonxml::browse='';
  141: 
  142: # JB, 9/24/2002: Any changes in this function may require a change
  143: # in lonnavmaps::resource::getDateStatus.
  144: sub check_access {
  145:   my ($id) = @_;
  146:   my $date ='';
  147:   my $status;
  148:   my $datemsg = '';
  149:   my $lastdate = '';
  150:   my $temp;
  151:   my $type;
  152:   my $passed;
  153:   &Apache::lonxml::debug("checking for part :$id:");
  154:   &Apache::lonxml::debug("time:".time);
  155:   foreach $temp ("opendate","duedate","answerdate") {
  156:     $lastdate = $date;
  157:     $date = &Apache::lonnet::EXT("resource.$id.$temp");
  158:     my $thistype = &Apache::lonnet::EXT("resource.$id.$temp.type");
  159:     if ($thistype =~ /^(con_lost|no_such_host)/ ||
  160: 	$date     =~ /^(con_lost|no_such_host)/) {
  161: 	$status='UNAVAILABLE';
  162: 	$date="may open later.";
  163: 	return($status,$date);
  164:     }
  165:     if ($thistype eq 'date_interval') {
  166: 	if ($temp eq 'opendate') {
  167:            $date=&Apache::lonnet::EXT("resource.$id.duedate")-$date;
  168:         }
  169:         if ($temp eq 'answerdate') {
  170:            $date=&Apache::lonnet::EXT("resource.$id.duedate")+$date;
  171:         }
  172:     }
  173:     &Apache::lonxml::debug("found :$date: for :$temp:");
  174:     if ($date eq '') {
  175:       $date = "an unknown date"; $passed = 0;
  176:     } elsif ($date eq 'con_lost') {
  177:       $date = "an indeterminate date"; $passed = 0;
  178:     } else {
  179:       if (time < $date) { $passed = 0; } else { $passed = 1; }
  180:       $date = localtime $date;
  181:     }
  182:     if (!$passed) { $type=$temp; last; }
  183:   }
  184:   &Apache::lonxml::debug("have :$type:$passed:");
  185:   if ($passed) {
  186:     $status='SHOW_ANSWER';
  187:     $datemsg=$date;
  188:   } elsif ($type eq 'opendate') {
  189:     $status='CLOSED';
  190:     $datemsg = "will open on $date";
  191:   } elsif ($type eq 'duedate') {
  192:     $status='CAN_ANSWER';
  193:     $datemsg = "is due at $date";
  194:   } elsif ($type eq 'answerdate') {
  195:     $status='CLOSED';
  196:     $datemsg = "was due on $lastdate, and answers will be available on $date";
  197:   }
  198:   if ($status eq 'CAN_ANSWER') {
  199:     #check #tries
  200:     my $tries = $Apache::lonhomework::history{"resource.$id.tries"};
  201:     my $maxtries = &Apache::lonnet::EXT("resource.$id.maxtries");
  202:     if ( $tries eq '' ) { $tries = '0'; }
  203:     if ( $maxtries eq '' ) { $maxtries = '2'; } 
  204:     if ($tries >= $maxtries) { $status = 'CANNOT_ANSWER'; } 
  205:   }
  206: 
  207:   if (($status ne 'CLOSED') && ($Apache::lonhomework::type eq 'exam') &&
  208:       (!$Apache::lonhomework::history{"resource.0.outtoken"})) {
  209:       return ('UNCHECKEDOUT','needs to be checked out');
  210:   }
  211: 
  212: 
  213:   &Apache::lonxml::debug("sending back :$status:$datemsg:");
  214:   if (($Apache::lonhomework::browse eq 'F') && ($status eq 'CLOSED')) {
  215:     &Apache::lonxml::debug("should be allowed to browse a resource when closed");
  216:     $status='CAN_ANSWER';
  217:     $datemsg='is closed but you are allowed to view it';
  218:   }
  219:   if ($ENV{'request.state'} eq "construct") {
  220:     &Apache::lonxml::debug("in construction ignoring dates");
  221:     $status='CAN_ANSWER';
  222:     $datemsg='is in under construction';
  223:   }
  224:   return ($status,$datemsg);
  225: }
  226: 
  227: sub showhash {
  228:   my (%hash) = @_;
  229:   &showhashsubset(\%hash,'.');
  230:   return '';
  231: }
  232: 
  233: sub showhashsubset {
  234:   my ($hash,$keyre) = @_;
  235:   my $resultkey;
  236:   foreach $resultkey (sort keys %$hash) {
  237:     if ($resultkey =~ /$keyre/) {
  238:       if (ref($$hash{$resultkey})) {
  239: 	if ($$hash{$resultkey} =~ /ARRAY/ ) {
  240: 	  my $string="$resultkey ---- (";
  241: 	  foreach my $elm (@{ $$hash{$resultkey} }) {
  242: 	    $string.="$elm,";
  243: 	  }
  244: 	  chop($string);
  245: 	  &Apache::lonxml::debug("$string)");
  246: 	} else {
  247: 	  &Apache::lonxml::debug("$resultkey ---- $$hash{$resultkey}");
  248: 	}
  249:       } else {
  250: 	&Apache::lonxml::debug("$resultkey ---- $$hash{$resultkey}");
  251:       }
  252:     }
  253:   }
  254:   &Apache::lonxml::debug("\n<br />restored values^</br>\n");
  255:   return '';
  256: }
  257: 
  258: sub setuppermissions {
  259:   $Apache::lonhomework::browse= &Apache::lonnet::allowed('bre',$ENV{'request.filename'});
  260:   $Apache::lonhomework::viewgrades=&Apache::lonnet::allowed('vgr',$ENV{'request.course.id'});
  261:   return ''
  262: }
  263: 
  264: sub setupheader {
  265:   my $request=$_[0];
  266:   if ($ENV{'browser.mathml'}) {
  267:     $request->content_type('text/xml');
  268:   } else {
  269:     $request->content_type('text/html');
  270:   }
  271:   if (!$Apache::lonxml::debug && ($ENV{'REQUEST_METHOD'} eq 'GET')) {
  272:     &Apache::loncommon::no_cache($request);
  273:   }
  274:   $request->send_http_header;
  275:   return OK if $request->header_only;
  276:   return ''
  277: }
  278: 
  279: sub handle_save_or_undo {
  280:   my ($request,$problem,$result) = @_;
  281:   my $file    = &Apache::lonnet::filelocation("",$request->uri);
  282:   my $filebak =$file.".bak";
  283:   my $filetmp =$file.".tmp";
  284:   my $error=0;
  285: 
  286:   if ($ENV{'form.Undo'} eq 'undo') {
  287:     my $error=0;
  288:     if (!copy($file,$filetmp)) { $error=1; }
  289:     if ((!$error) && (!copy($filebak,$file))) { $error=1; }
  290:     if ((!$error) && (!move($filetmp,$filebak))) { $error=1; }
  291:     if (!$error) {
  292:       $request->print("<p><b>Undid changes, Switched $filebak and $file</b></p>");
  293:     } else {
  294:       $request->print("<p><font color=\"red\" size=\"+1\"><b>Unable to undo, unable to switch $filebak and $file</b></font></p>");
  295:       $error=1;
  296:     }
  297:   } else {
  298:     my $fs=Apache::File->new(">$filebak");
  299:     if (defined($fs)) {
  300:       print $fs $$problem;
  301:       $request->print("<b>Making Backup to $filebak</b><br />");
  302:     } else {
  303:       $request->print("<font color=\"red\" size=\"+1\"><b>Unable to make backup $filebak</b></font>");
  304:       $error=2;
  305:     }
  306:     my $fh=Apache::File->new(">$file");
  307:     if (defined($fh)) {
  308:       print $fh $$result;
  309:       $request->print("<b>Saving Modifications to $file</b><br />");
  310:     } else {
  311:       $request->print("<font color=\"red\" size=\"+1\"><b>Unable to write to $file</b></font>");
  312:       $error|=4;
  313:     }
  314:   }
  315:   return $error;
  316: }
  317: 
  318: sub analyze_header {
  319:     my ($request) = @_;
  320:     my $result.='<html><body bgcolor="#FFFFFF">
  321:             <form name="lonhomework" method="POST" action="'.
  322: 	      $ENV{'request.uri'}.'">
  323:             <input type="submit" name="problemmode" value="EditXML" />
  324:             <input type="submit" name="problemmode" value="Edit" />
  325:             <hr />
  326:             <input type="submit" name="submit" value="View" />
  327:             <hr />
  328:             List of possible answers:
  329:             </form>';
  330:     $request->print($result);
  331:     $request->rflush();
  332: }
  333: 
  334: sub analyze {
  335:     my ($request,$file) = @_;
  336:     &Apache::lonxml::debug("Analyze");
  337:     my $result;
  338:     my %overall;
  339:     my %allparts;
  340:     my $rndseed=$ENV{'form.rndseed'};
  341:     &analyze_header($request);
  342:     for(my $i=1;$i<$ENV{'form.numtoanalyze'}+1;$i++) {
  343: 	my $subresult=&Apache::lonnet::ssi($request->uri,
  344: 					   ('grade_target' => 'analyze'),
  345: 					   ('rndseed' => $i));
  346: 	&Apache::lonxml::debug(":$subresult:");
  347: 	(my $garbage,$subresult)=split(/_HASH_REF__/,$subresult,2);
  348: 	my %analyze=&Apache::lonnet::str2hash($subresult);
  349: 	&Apache::lonhomework::showhash(%analyze);
  350: 	my @parts = @{ $analyze{'parts'} };
  351: 	foreach my $part (@parts) {
  352: 	    if (!exists($allparts{$part})) {$allparts{$part}=1;};
  353: 	    if ($analyze{$part.'.type'} eq 'numericalresponse') {
  354: 		push( @{ $overall{$part.'.answer'} },
  355: 		      [@{ $analyze{$part.'.answer'} }]);
  356: 	    }
  357: 	}
  358:     }
  359:     foreach my $part (keys(%allparts)) {
  360: 	$request->print('<table><tr><td>Part '.$part.'</td></tr>');
  361: 	foreach my $answer (sort {$a->[0] <=> $b->[0]} (@{ $overall{$part.'.answer'} })) {
  362: 	    $request->print('<tr><td>'.join('</td><td>',@{ $answer }).
  363: 			    '</td></tr>');
  364: 	}
  365:     }
  366:     &Apache::lonhomework::showhash(%overall);
  367:     return $result;
  368: }
  369: 
  370: sub editxmlmode {
  371:   my ($request,$file) = @_;
  372:   my $result;
  373:   my $problem=&Apache::lonnet::getfile($file);
  374:   if ($problem == -1) {
  375:     &Apache::lonxml::error("<b> Unable to find <i>$file</i></b>");
  376:     $problem='';
  377:   }
  378:   if (defined($ENV{'form.editxmltext'}) || defined($ENV{'form.Undo'})) {
  379:     my $error=&handle_save_or_undo($request,\$problem,
  380: 				   \$ENV{'form.editxmltext'});
  381:     if (!$error) { $problem=&Apache::lonnet::getfile($file); }
  382:   }
  383:   &Apache::lonhomework::showhashsubset(\%ENV,'^form');
  384:   if ( $ENV{'form.submit'} eq 'Submit Changes and View' ) {
  385:     &Apache::lonhomework::showhashsubset(\%ENV,'^form');
  386:     $ENV{'form.problemmode'}='View';
  387:     &renderpage($request,$file);
  388:   } else {
  389:     my ($rows,$cols) = &Apache::edit::textarea_sizes(\$problem);
  390:     my $xml_help = Apache::loncommon::help_open_topic("Problem_Editor_XML_Index");
  391:     if ($cols > 80) { $cols = 80; }
  392:     if ($cols < 70) { $cols = 70; }
  393:     if ($rows < 20) { $rows = 20; }
  394:     $result.='<html><body bgcolor="#FFFFFF">
  395:             <form name="lonhomework" method="POST" action="'.
  396: 	      $ENV{'request.uri'}.'">
  397:             <input type="hidden" name="problemmode" value="EditXML" />
  398:             <input type="submit" name="problemmode" value="Discard Edits and View" />
  399:             <input type="submit" name="problemmode" value="Edit" />
  400:             <hr />
  401:             <input type="submit" name="submit" value="Submit Changes" />
  402:             <input type="submit" name="submit" value="Submit Changes and View" />
  403:             <input type="submit" name="Undo" value="undo" />
  404:             <hr />
  405:             ' . $xml_help . ' Problem Help<br>
  406:             <textarea rows="'.$rows.'" cols="'.$cols.'" name="editxmltext">'.
  407: 	      &HTML::Entities::encode($problem).'</textarea>
  408:             </form></body></html>';
  409:     $request->print($result);
  410:   }
  411:   return '';
  412: }
  413: 
  414: sub renderpage {
  415:   my ($request,$file) = @_;
  416: 
  417:   my (@targets) = &get_target();
  418:   &Apache::lonxml::debug("Running targets ".join(':',@targets));
  419:   foreach my $target (@targets) {
  420:     #my $t0 = [&gettimeofday()];
  421:     my $problem=&Apache::lonnet::getfile($file);
  422:     if ($problem == -1) {
  423:       &Apache::lonxml::error("<b> Unable to find <i>$file</i></b>");
  424:       $problem='';
  425:     }
  426: 
  427:     my %mystyle;
  428:     my $result = '';
  429:     &Apache::inputtags::initialize_inputtags();
  430:     &Apache::outputtags::initialize_outputtags();
  431:     &Apache::edit::initialize_edit();
  432:     if ($target eq 'analyze') { %Apache::lonhomework::anaylze=(); }
  433:     if ($target eq 'answer') { &showhash(%Apache::lonhomework::history); }
  434:     if ($target eq 'web') {&Apache::lonhomework::showhashsubset(\%ENV,'^form');}
  435: 
  436:     &Apache::lonxml::debug("Should be parsing now");
  437:     $result = &Apache::lonxml::xmlparse($request, $target, $problem,
  438: 			&setup_vars($target),%mystyle);
  439: 
  440:     #$request->print("Result follows:");
  441:     if ($target eq 'modified') {
  442:       &handle_save_or_undo($request,\$problem,\$result);
  443:     } else {
  444:       if ($target eq 'analyze') {
  445: 	$result=&Apache::lonnet::hashref2str(\%Apache::lonhomework::analyze);
  446: 	undef(%Apache::lonhomework::analyze);
  447:       }
  448:       #my $td=&tv_interval($t0);
  449:       #if ( $Apache::lonxml::debug) {
  450: 	#$result =~ s:</body>::;
  451: 	#$result.="<br />Spent $td seconds processing target $target\n</body>";
  452:       #}
  453:       $request->print($result);
  454:     }
  455:     #$request->print(":Result ends");
  456:     #my $td=&tv_interval($t0);
  457:   }
  458: }
  459: 
  460: # with no arg it returns a HTML <option> list of the template titles
  461: # with one arg it returns the filename associated with the arg passed
  462: sub get_template_list {
  463:   my ($namewanted,$extension) = @_;
  464:   my $result;
  465:   my @allnames;
  466:   &Apache::lonxml::debug("Looking for :$extension:");
  467:   foreach my $file (</home/httpd/html/res/adm/includes/templates/*.$extension>) {
  468:     my $name=&Apache::lonnet::metadata($file,'title');
  469:     if ($namewanted && ($name eq $namewanted)) {
  470:       $result=$file;
  471:       last;
  472:     } else {
  473:       push (@allnames, $name);
  474:     }
  475:   }
  476:   if (@allnames && !$result) {
  477:     $result="<option>Select a $extension type</option>\n<option>".
  478:       join('</option><option>',sort(@allnames)).'</option>';
  479:   }
  480:   return $result;
  481: }
  482: 
  483: sub newproblem {
  484:     my ($request) = @_;
  485:     my $extension=$request->uri;
  486:     $extension=~s:^.*\.([\w]+)$:$1:;
  487:     &Apache::lonxml::debug("Looking for :$extension:");
  488:     if ($ENV{'form.template'} &&
  489: 	$ENV{'form.template'} ne "Select a $extension type") {
  490: 	use File::Copy;
  491: 	my $file = &get_template_list($ENV{'form.template'},$extension);
  492: 	my $dest = &Apache::lonnet::filelocation("",$request->uri);
  493: 	copy($file,$dest);
  494: 	&renderpage($request,$dest);
  495:     } elsif($ENV{'form.newfile'}) {
  496: 	# I don't like hard-coded filenames but for now, this will work.
  497: 	use File::Copy;
  498: 	my $templatefilename = 
  499: 	    $request->dir_config('lonIncludes').'/templates/blank.problem';
  500: 	&Apache::lonxml::debug("$templatefilename");
  501: 	my $dest = &Apache::lonnet::filelocation("",$request->uri);
  502: 	copy($templatefilename,$dest);
  503: 	&renderpage($request,$dest);
  504:     } else {
  505: 	my $templatelist=&get_template_list('',$extension);
  506: 	my $url=$request->uri;
  507: 	my $dest = &Apache::lonnet::filelocation("",$request->uri);
  508: 	my $instructions;
  509: 	if ($templatelist) { $instructions=", select a template from the pull-down menu below. Then";}
  510: 	$request->print(<<ENDNEWPROBLEM);
  511: <body bgcolor="#FFFFFF">
  512: The requested file $url doesn\'t exist. <br />
  513: To create a new $extension$instructions click on the Create $extension button.
  514: <form action="$url" method="POST">
  515: ENDNEWPROBLEM
  516: 	if (defined($templatelist)) {
  517: 	    $request->print("<select name=\"template\">$templatelist</select>");
  518: 	}
  519: 	$request->print("<br /><input type=\"submit\" name=\"newfile\" value=\"Create $extension\" />");
  520: 	$request->print("</form></body>");
  521:     }
  522:     return '';
  523: }
  524: 
  525: sub view_or_edit_menu {
  526:   my ($request) = @_;
  527:   my $url=$request->uri;
  528:   $request->print(<<EDITMENU);
  529: <body bgcolor="#FFFFFF">
  530: <form action="$url" method="POST">
  531: Would you like to <input type="submit" name="problemmode" value="View"> or
  532: <input type="submit" name="problemmode" value="Edit"> the problem.
  533: </form>
  534: </body>
  535: EDITMENU
  536: }
  537: 
  538: sub handler {
  539:   #my $t0 = [&gettimeofday()];
  540:   my $request=$_[0];
  541: 
  542: #  if ( $ENV{'user.name'} eq 'albertel' ) {$Apache::lonxml::debug=1;}
  543:   $Apache::lonxml::debug=$ENV{'user.debug'};
  544: 
  545:   if (&setupheader($request)) { return OK; }
  546:   $ENV{'request.uri'}=$request->uri;
  547: 
  548:   #setup permissions
  549:   $Apache::lonhomework::browse= &Apache::lonnet::allowed('bre',$ENV{'request.filename'});
  550:   $Apache::lonhomework::viewgrades=&Apache::lonnet::allowed('vgr',$ENV{'request.course.id'});
  551:   &Apache::lonxml::debug("Permissions:$Apache::lonhomework::browse:$Apache::lonhomework::viewgrades:");
  552:   # some times multiple problemmodes are submitted, need to select
  553:   # the last one
  554:   &Apache::lonxml::debug("Problem Mode ".$ENV{'form.problemmode'});
  555:   if ( defined($ENV{'form.problemmode'}) &&
  556:        ref($ENV{'form.problemmode'}) ) {
  557:     &Apache::lonxml::debug("Problem Mode ".join(",",@$ENV{'form.problemmode'}));
  558:     my $mode=$ENV{'form.problemmode'}->[-1];
  559:     undef $ENV{'form.problemmode'};
  560:     $ENV{'form.problemmode'}=$mode;
  561:   }
  562:   &Apache::lonxml::debug("Problem Mode ".$ENV{'form.problemmode'});
  563:   my $file=&Apache::lonnet::filelocation("",$request->uri);
  564: 
  565:   #check if we know where we are
  566:   if ($ENV{'request.course.fn'} && !&Apache::lonnet::symbread()) { 
  567:     # if we are browsing we might not be able to know where we are
  568:     if ($Apache::lonhomework::browse ne 'F') {
  569:       #should know where we are, so ask
  570:       $request->internal_redirect('/adm/ambiguous'); return;
  571:     }
  572:   }
  573: 
  574:   if ($ENV{'request.state'} eq "construct") {
  575:     if ($ENV{'form.resetdata'} eq 'Reset Submissions') {
  576:       my ($symb,$courseid,$domain,$name) = &Apache::lonxml::whichuser();
  577:       &Apache::lonnet::tmpreset($symb,'',$domain,$name);
  578:     }
  579:     if ( -e $file ) {
  580:       if (!(defined $ENV{'form.problemmode'})) {
  581: 	#first visit to problem in construction space
  582: 	#&view_or_edit_menu($request);
  583: 	$ENV{'form.problemmode'}='View';
  584: 	&renderpage($request,$file);
  585:       } elsif ($ENV{'form.problemmode'} eq 'EditXML') {
  586: 	&editxmlmode($request,$file);
  587:       } elsif ($ENV{'form.problemmode'} eq 'Answer Distribution') {
  588: 	&analyze($request,$file);
  589:       } else {
  590: 	&renderpage($request,$file);
  591:       }
  592:     } else {
  593:       # requested file doesn't exist in contruction space
  594:       &newproblem($request);
  595:     }
  596:   } else {
  597:     # just render the page normally outside of construction space
  598:     &Apache::lonxml::debug("not construct");
  599:     &renderpage($request,$file);
  600:   }
  601:   #my $td=&tv_interval($t0);
  602:   #&Apache::lonxml::debug("Spent $td seconds processing");
  603:   # &Apache::lonhomework::send_footer($request);
  604:   # always turn off debug messages
  605:   $Apache::lonxml::debug=0;
  606:   return OK;
  607: 
  608: }
  609: 
  610: 1;
  611: __END__