Annotation of rat/lonuserstate.pm, revision 1.148

1.1       www         1: # The LearningOnline Network with CAPA
                      2: # Construct and maintain state and binary representation of course for user
                      3: #
1.148   ! raeburn     4: # $Id: lonuserstate.pm,v 1.147 2013/08/16 01:41:05 raeburn Exp $
1.25      www         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: #
1.26      harris41   28: ###
1.1       www        29: 
                     30: package Apache::lonuserstate;
                     31: 
1.26      harris41   32: # ------------------------------------------------- modules used by this module
1.1       www        33: use strict;
                     34: use HTML::TokeParser;
1.89      albertel   35: use Apache::lonnet;
1.114     www        36: use Apache::lonlocal;
1.26      harris41   37: use Apache::loncommon();
1.1       www        38: use GDBM_File;
1.12      www        39: use Apache::lonmsg;
1.15      www        40: use Safe;
1.21      www        41: use Safe::Hole;
1.15      www        42: use Opcode;
1.73      www        43: use Apache::lonenc;
1.96      albertel   44: use Fcntl qw(:flock);
1.114     www        45: use LONCAPA;
1.138     foxr       46: use File::Basename;
                     47: 
1.114     www        48:  
1.15      www        49: 
1.1       www        50: # ---------------------------------------------------- Globals for this package
                     51: 
1.138     foxr       52: my $pc;      # Package counter is this what 'Guts' calls the map counter?
1.1       www        53: my %hash;    # The big tied hash
1.19      www        54: my %parmhash;# The hash with the parameters
1.1       www        55: my @cond;    # Array with all of the conditions
                     56: my $errtext; # variable with all errors
1.116     www        57: my $retfrid; # variable with the very first RID in the course
                     58: my $retfurl; # first URL
1.29      www        59: my %randompick; # randomly picked resources
1.51      www        60: my %randompickseed; # optional seed for randomly picking resources
1.124     albertel   61: my %randomorder; # maps to order contents randomly
1.146     raeburn    62: my %randomizationcode; # code used to grade folder for bubblesheet exam 
1.73      www        63: my %encurl; # URLs in this folder are supposed to be encrypted
                     64: my %hiddenurl; # this URL (or complete folder) is supposed to be hidden
1.61      www        65: 
                     66: # ----------------------------------- Remove version from URL and store in hash
                     67: 
1.134     www        68: sub versionerror {
                     69:     my ($uri,$usedversion,$unusedversion)=@_;
                     70:     return '<br />'.&mt('Version discrepancy: resource [_1] included in both version [_2] and version [_3]. Using version [_2].',
                     71:                     $uri,$usedversion,$unusedversion).'<br />';
                     72: }
                     73: 
1.139     foxr       74: #  Removes the version number from a URI and returns the resulting
                     75: #  URI (e.g. mumbly.version.stuff => mumbly.stuff).
                     76: #
                     77: #   If the URI has not been seen with a versio before the
                     78: #   hash{'version_'.resultingURI} is set to the  version number.
                     79: #   If the URI has been seen and the version does not match and error
                     80: #   is added to the error string.
                     81: #
                     82: # Parameters:
                     83: #   URI potentially with a version.
                     84: # Returns:
                     85: #   URI with the version cut out.
                     86: # See above for side effects.
                     87: #
                     88: 
1.61      www        89: sub versiontrack {
                     90:     my $uri=shift;
                     91:     if ($uri=~/\.(\d+)\.\w+$/) {
                     92: 	my $version=$1;
                     93: 	$uri=~s/\.\d+\.(\w+)$/\.$1/;
1.62      www        94:         unless ($hash{'version_'.$uri}) {
                     95: 	    $hash{'version_'.$uri}=$version;
1.134     www        96: 	} elsif ($version!=$hash{'version_'.$uri}) {
                     97:             $errtext.=&versionerror($uri,$hash{'version_'.$uri},$version);
                     98:         }
1.61      www        99:     }
                    100:     return $uri;
                    101: }
                    102: 
                    103: # -------------------------------------------------------------- Put in version
                    104: 
                    105: sub putinversion {
                    106:     my $uri=shift;
1.93      www       107:     my $key=$env{'request.course.id'}.'_'.&Apache::lonnet::clutter($uri);
1.61      www       108:     if ($hash{'version_'.$uri}) {
                    109: 	my $version=$hash{'version_'.$uri};
1.65      www       110: 	if ($version eq 'mostrecent') { return $uri; }
1.66      www       111: 	if ($version eq &Apache::lonnet::getversion(
                    112: 			&Apache::lonnet::filelocation('',$uri))) 
                    113: 	             { return $uri; }
1.61      www       114: 	$uri=~s/\.(\w+)$/\.$version\.$1/;
                    115:     }
1.93      www       116:     &Apache::lonnet::do_cache_new('courseresversion',$key,&Apache::lonnet::declutter($uri),600);
1.61      www       117:     return $uri;
                    118: }
                    119: 
                    120: # ----------------------------------------- Processing versions file for course
                    121: 
                    122: sub processversionfile {
1.64      www       123:     my %cenv=@_;
1.61      www       124:     my %versions=&Apache::lonnet::dump('resourceversions',
                    125: 				       $cenv{'domain'},
                    126: 				       $cenv{'num'});
1.106     albertel  127:     foreach my $ver (keys(%versions)) {
                    128: 	if ($ver=~/^error\:/) { return; }
                    129: 	$hash{'version_'.$ver}=$versions{$ver};
1.61      www       130:     }
                    131: }
1.45      www       132: 
1.138     foxr      133: # --------------------------------------------------------- Loads from disk
1.1       www       134: 
1.140     foxr      135: 
                    136: #
                    137: #  Loads a map file.
                    138: #  Note that this may implicitly recurse via parse_resource if one of the resources
                    139: #  is itself composed.
                    140: #
                    141: # Parameters:
                    142: #    uri         - URI of the map file.
                    143: #    parent_rid  - Resource id in the map of the parent resource (0.0 for the top level map)
1.146     raeburn   144: #    courseid    - Course id for the course for which the map is being loaded
1.140     foxr      145: #
1.1       www       146: sub loadmap { 
1.146     raeburn   147:     my ($uri,$parent_rid,$courseid)=@_;
1.138     foxr      148: 
                    149:     # Is the map already included?
                    150: 
1.114     www       151:     if ($hash{'map_pc_'.$uri}) { 
1.120     albertel  152: 	$errtext.='<p class="LC_error">'.
                    153: 	    &mt('Multiple use of sequence/page [_1]! The course will not function properly.','<tt>'.$uri.'</tt>').
                    154: 	    '</p>';
1.114     www       155: 	return; 
                    156:     }
1.138     foxr      157:     # Register the resource in it's map_pc_ [for the URL]
                    158:     # map_id.nnn is the nesting level -> to the URI.
                    159: 
1.1       www       160:     $pc++;
                    161:     my $lpc=$pc;
                    162:     $hash{'map_pc_'.$uri}=$lpc;
                    163:     $hash{'map_id_'.$lpc}=$uri;
1.138     foxr      164: 
                    165:     # If the parent is of the form n.m hang this map underneath it in the
                    166:     # map hierarchy.
                    167: 
1.136     raeburn   168:     if ($parent_rid =~ /^(\d+)\.\d+$/) {
                    169:         my $parent_pc = $1;
                    170:         if (defined($hash{'map_hierarchy_'.$parent_pc})) {
                    171:             $hash{'map_hierarchy_'.$lpc}=$hash{'map_hierarchy_'.$parent_pc}.','.
                    172:                                          $parent_pc;
                    173:         } else {
                    174:             $hash{'map_hierarchy_'.$lpc}=$parent_pc;
                    175:         }
                    176:     }
1.1       www       177: 
1.138     foxr      178: # Determine and check filename of the sequence we need to read:
                    179: 
1.62      www       180:     my $fn=&Apache::lonnet::filelocation('',&putinversion($uri));
1.37      www       181: 
                    182:     my $ispage=($fn=~/\.page$/);
1.1       www       183: 
1.138     foxr      184:     # We can only nest sequences or pages.  Anything else is an illegal nest.
                    185: 
                    186:     unless (($fn=~/\.sequence$/) || $ispage) { 
1.147     raeburn   187: 	$errtext.='<br />'.&mt('Invalid map: [_1]',"<tt>$fn</tt>");
1.98      albertel  188: 	return; 
1.1       www       189:     }
                    190: 
1.138     foxr      191:     # Read the XML that constitutes the file.
                    192: 
1.37      www       193:     my $instr=&Apache::lonnet::getfile($fn);
                    194: 
1.124     albertel  195:     if ($instr eq -1) {
1.147     raeburn   196:         $errtext.= '<br />'
                    197:                   .&mt('Map not loaded: The file [_1] does not exist.',
                    198:                        "<tt>$fn</tt>");
1.124     albertel  199: 	return;
                    200:     }
1.22      www       201: 
1.138     foxr      202:     # Successfully got file, parse it
                    203: 
                    204:     # parse for parameter processing.
                    205:     # Note that these are <param... / > tags
                    206:     # so we only care about 'S' (tag start) nodes.
                    207: 
1.1       www       208: 
1.124     albertel  209:     my $parser = HTML::TokeParser->new(\$instr);
                    210:     $parser->attr_encoded(1);
1.138     foxr      211: 
1.124     albertel  212:     # first get all parameters
1.138     foxr      213: 
                    214: 
1.124     albertel  215:     while (my $token = $parser->get_token) {
                    216: 	next if ($token->[0] ne 'S');
                    217: 	if ($token->[1] eq 'param') {
                    218: 	    &parse_param($token,$lpc);
                    219: 	} 
                    220:     }
1.138     foxr      221: 
                    222:     # Get set to take another pass through the XML:
                    223:     # for resources and links.
                    224: 
1.124     albertel  225:     $parser = HTML::TokeParser->new(\$instr);
                    226:     $parser->attr_encoded(1);
1.1       www       227: 
1.124     albertel  228:     my $linkpc=0;
1.1       www       229: 
1.124     albertel  230:     $fn=~/\.(\w+)$/;
1.1       www       231: 
1.124     albertel  232:     $hash{'map_type_'.$lpc}=$1;
1.1       www       233: 
1.124     albertel  234:     my $randomize = ($randomorder{$parent_rid} =~ /^yes$/i);
1.1       www       235: 
1.138     foxr      236:     # Parse the resources, link and condition tags.
                    237:     # Note that if randomorder or random select is chosen the links and
                    238:     # conditions are meaningless but are determined by the randomization.
                    239:     # This is handled in the next chunk of code.
                    240: 
1.124     albertel  241:     my @map_ids;
1.146     raeburn   242:     my $codechecked;
1.124     albertel  243:     while (my $token = $parser->get_token) {
                    244: 	next if ($token->[0] ne 'S');
1.138     foxr      245: 
                    246: 	# Resource
                    247: 
1.124     albertel  248: 	if ($token->[1] eq 'resource') {
1.146     raeburn   249: 	    my $resource_id = &parse_resource($token,$lpc,$ispage,$uri,$courseid);
1.138     foxr      250: 	    if (defined $resource_id) {
1.146     raeburn   251: 		push(@map_ids, $resource_id);
                    252:                 unless ($codechecked) {
                    253:                     my $startsymb =
                    254:                        &Apache::lonnet::encode_symb($hash{'map_id_'.$lpc},$resource_id,
                    255:                                                     $hash{'src_'."$lpc.$resource_id"});
                    256:                     my $code = 
                    257:                         &Apache::lonnet::EXT('resource.0.examcode',$startsymb,undef,undef,
                    258:                                              undef,undef,$courseid);
                    259:                     if ($code) {
                    260:                         $randomizationcode{$parent_rid} = $code;
                    261:                     }
                    262:                     $codechecked = 1; 
                    263:                 }
1.138     foxr      264: 	    }
                    265: 
                    266:        # Link
                    267: 
1.124     albertel  268: 	} elsif ($token->[1] eq 'link' && !$randomize) {
                    269: 	    &make_link(++$linkpc,$lpc,$token->[2]->{'to'},
                    270: 		       $token->[2]->{'from'},
1.139     foxr      271: 		       $token->[2]->{'condition'}); # note ..condition may be undefined.
1.138     foxr      272: 
                    273: 	# condition
                    274: 
1.124     albertel  275: 	} elsif ($token->[1] eq 'condition' && !$randomize) {
                    276: 	    &parse_condition($token,$lpc);
                    277: 	}
                    278:     }
1.146     raeburn   279:     undef($codechecked);
1.1       www       280: 
1.138     foxr      281: 
                    282:     # Handle randomization and random selection
                    283: 
1.124     albertel  284:     if ($randomize) {
1.148   ! raeburn   285:         my $advanced;
        !           286:         if ($env{'request.course.id'}) {
        !           287:             $advanced = (&Apache::lonnet::allowed('adv') eq 'F');
        !           288:         } else {
        !           289:             $env{'request.course.id'} = $courseid;
        !           290:             $advanced = (&Apache::lonnet::allowed('adv') eq 'F');
        !           291:             $env{'request.course.id'} = '';
        !           292:         }
        !           293:         unless ($advanced) {
        !           294:             # Order of resources is not randomized if user has and advanced role in the course.
1.124     albertel  295: 	    my $seed;
1.139     foxr      296: 
1.148   ! raeburn   297:             # If the map's random seed parameter has been specified
        !           298:             # it is used as the basis for computing the seed ...
1.139     foxr      299: 
1.124     albertel  300: 	    if (defined($randompickseed{$parent_rid})) {
                    301: 		$seed = $randompickseed{$parent_rid};
                    302: 	    } else {
1.139     foxr      303: 
                    304: 		# Otherwise the parent's fully encoded symb is used.
                    305: 
1.124     albertel  306: 		my ($mapid,$resid)=split(/\./,$parent_rid);
                    307: 		my $symb=
                    308: 		    &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},
                    309: 						 $resid,$hash{'src_'.$parent_rid});
1.85      albertel  310: 		
1.124     albertel  311: 		$seed = $symb;
                    312: 	    }
1.138     foxr      313: 
1.139     foxr      314: 	    # TODO: Here for sure we need to pass along the username/domain
1.138     foxr      315: 	    # so that we can impersonate users in lonprintout e.g.
                    316: 
1.146     raeburn   317:             my $setcode;
                    318:             if (defined($randomizationcode{$parent_rid})) {
                    319:                 if ($env{'form.CODE'} eq '') {
                    320:                     $env{'form.CODE'} = $randomizationcode{$parent_rid};
                    321:                     $setcode = 1;
                    322:                 }
                    323:             }
                    324: 
1.124     albertel  325: 	    my $rndseed=&Apache::lonnet::rndseed($seed);
                    326: 	    &Apache::lonnet::setup_random_from_rndseed($rndseed);
1.140     foxr      327: 
1.146     raeburn   328:             if ($setcode) {
                    329:                 undef($env{'form.CODE'});
                    330:                 undef($setcode);
                    331:             }
                    332: 
1.140     foxr      333: 	    # Take the set of map ids we have decoded and permute them to a
                    334: 	    # random order based on the seed set above. All of this is
                    335: 	    # processing the randomorder parameter if it is set, not
                    336: 	    # randompick.
                    337: 
1.148   ! raeburn   338: 	    @map_ids=&Math::Random::random_permutation(@map_ids);
1.124     albertel  339: 	}
1.139     foxr      340: 
                    341: 
1.124     albertel  342: 	my $from = shift(@map_ids);
                    343: 	my $from_rid = $lpc.'.'.$from;
                    344: 	$hash{'map_start_'.$uri} = $from_rid;
                    345: 	$hash{'type_'.$from_rid}='start';
                    346: 
1.140     foxr      347: 	# Create links to reflect the random re-ordering done above.
                    348: 	# In the code to process the map XML, we did not process links or conditions
                    349: 	# if randomorder was set.  This means that for an instructor to choose
1.139     foxr      350: 
1.124     albertel  351: 	while (my $to = shift(@map_ids)) {
                    352: 	    &make_link(++$linkpc,$lpc,$to,$from);
                    353: 	    my $to_rid =  $lpc.'.'.$to;
                    354: 	    $hash{'type_'.$to_rid}='normal';
                    355: 	    $from = $to;
                    356: 	    $from_rid = $to_rid;
                    357: 	}
1.1       www       358: 
1.124     albertel  359: 	$hash{'map_finish_'.$uri}= $from_rid;
                    360: 	$hash{'type_'.$from_rid}='finish';
1.1       www       361:     }
1.121     albertel  362: 
1.127     albertel  363:     $parser = HTML::TokeParser->new(\$instr);
1.121     albertel  364:     $parser->attr_encoded(1);
1.139     foxr      365: 
1.140     foxr      366:     # last parse out the mapalias params.  Thes provide mnemonic
                    367:     # tags to resources that can be used in conditions
1.139     foxr      368: 
1.121     albertel  369:     while (my $token = $parser->get_token) {
                    370: 	next if ($token->[0] ne 'S');
                    371: 	if ($token->[1] eq 'param') {
                    372: 	    &parse_mapalias_param($token,$lpc);
                    373: 	} 
                    374:     }
                    375: }
                    376: 
1.124     albertel  377: 
                    378: # -------------------------------------------------------------------- Resource
1.138     foxr      379: #
                    380: #  Parses a resource tag to produce the value to push into the
                    381: #  map_ids array.
                    382: # 
                    383: #
                    384: #  Information about the actual type of resource is provided by the file extension
                    385: #  of the uri (e.g. .problem, .sequence etc. etc.).
                    386: #
                    387: #  Parameters:
                    388: #    $token   - A token from HTML::TokeParser
                    389: #               This is an array that describes the most recently parsed HTML item.
                    390: #    $lpc     - Map nesting level (?)
                    391: #    $ispage  - True if this resource is encapsulated in a .page (assembled resourcde).
                    392: #    $uri     - URI of the enclosing resource.
1.146     raeburn   393: #    $courseid - Course id of the course containing the resource being parsed. 
1.138     foxr      394: # Returns:
1.139     foxr      395: #   Value of the id attribute of the tag.
1.138     foxr      396: #
                    397: # Note:
                    398: #   The token is an array that contains the following elements:
                    399: #   [0]   => 'S' indicating this is a start token
                    400: #   [1]   => 'resource'  indicating this tag is a <resource> tag.
                    401: #   [2]   => Hash of attribute =>value pairs.
                    402: #   [3]   => @(keys [2]).
                    403: #   [4]   => unused.
                    404: #
                    405: #   The attributes of the resourcde tag include:
                    406: #
                    407: #   id     - The resource id.
                    408: #   src    - The URI of the resource.
                    409: #   type   - The resource type (e.g. start and finish).
                    410: #   title  - The resource title.
                    411: 
                    412: 
1.124     albertel  413: sub parse_resource {
1.146     raeburn   414:     my ($token,$lpc,$ispage,$uri,$courseid) = @_;
1.138     foxr      415:     
1.139     foxr      416:     # I refuse to countenance code like this that has 
1.138     foxr      417:     # such a dirty side effect (and forcing this sub to be called within a loop).
                    418:     #
                    419:     #  if ($token->[2]->{'type'} eq 'zombie') { next; }
1.139     foxr      420:     #
                    421:     #  The original code both returns _and_ skips to the next pass of the >caller's<
                    422:     #  loop, that's just dirty.
                    423:     #
1.138     foxr      424: 
                    425:     # Zombie resources don't produce anything useful.
                    426: 
                    427:     if ($token->[2]->{'type'} eq 'zombie') {
                    428: 	return undef;
                    429:     }
                    430: 
1.139     foxr      431:     my $rid=$lpc.'.'.$token->[2]->{'id'}; # Resource id in hash is levelcounter.id-in-xml.
                    432: 
                    433:     # Save the hash element type and title:
1.124     albertel  434: 	    
                    435:     $hash{'kind_'.$rid}='res';
                    436:     $hash{'title_'.$rid}=$token->[2]->{'title'};
1.139     foxr      437: 
                    438:     # Get the version free URI for the resource.
                    439:     # If a 'version' attribute was supplied, and this resource's version 
                    440:     # information has not yet been stored, store it.
                    441:     #
                    442: 
1.124     albertel  443:     my $turi=&versiontrack($token->[2]->{'src'});
                    444:     if ($token->[2]->{'version'}) {
                    445: 	unless ($hash{'version_'.$turi}) {
                    446: 	    $hash{'version_'.$turi}=$1;
                    447: 	}
                    448:     }
1.139     foxr      449:     # Pull out the title and do entity substitution on &colon
                    450:     # Q: Why no other entity substitutions?
                    451: 
1.124     albertel  452:     my $title=$token->[2]->{'title'};
                    453:     $title=~s/\&colon\;/\:/gs;
1.139     foxr      454: 
                    455: 
                    456: 
                    457:     # I think the point of all this code is to construct a final
                    458:     # URI that apache and its rewrite rules can use to
                    459:     # fetch the resource.   Thi s sonly necessary if the resource
                    460:     # is not a page.  If the resource is a page then it must be
                    461:     # assembled (at fetch time?).
                    462: 
1.124     albertel  463:     unless ($ispage) {
                    464: 	$turi=~/\.(\w+)$/;
                    465: 	my $embstyle=&Apache::loncommon::fileembstyle($1);
                    466: 	if ($token->[2]->{'external'} eq 'true') { # external
1.130     raeburn   467: 	    $turi=~s/^https?\:\/\//\/adm\/wrapper\/ext\//;
1.124     albertel  468: 	} elsif ($turi=~/^\/*uploaded\//) { # uploaded
                    469: 	    if (($embstyle eq 'img') 
                    470: 		|| ($embstyle eq 'emb')
                    471: 		|| ($embstyle eq 'wrp')) {
                    472: 		$turi='/adm/wrapper'.$turi;
                    473: 	    } elsif ($embstyle eq 'ssi') {
                    474: 		#do nothing with these
                    475: 	    } elsif ($turi!~/\.(sequence|page)$/) {
                    476: 		$turi='/adm/coursedocs/showdoc'.$turi;
                    477: 	    }
                    478: 	} elsif ($turi=~/\S/) { # normal non-empty internal resource
                    479: 	    my $mapdir=$uri;
                    480: 	    $mapdir=~s/[^\/]+$//;
                    481: 	    $turi=&Apache::lonnet::hreflocation($mapdir,$turi);
                    482: 	    if (($embstyle eq 'img') 
                    483: 		|| ($embstyle eq 'emb')
                    484: 		|| ($embstyle eq 'wrp')) {
                    485: 		$turi='/adm/wrapper'.$turi;
                    486: 	    }
                    487: 	}
                    488:     }
1.139     foxr      489:     # Store reverse lookup, remove query string resource 'ids'_uri => resource id.
                    490:     # If the URI appears more than one time in the sequence, it's resourcde
                    491:     # id's are constructed as a comma spearated list.
                    492: 
1.124     albertel  493:     my $idsuri=$turi;
                    494:     $idsuri=~s/\?.+$//;
                    495:     if (defined($hash{'ids_'.$idsuri})) {
                    496: 	$hash{'ids_'.$idsuri}.=','.$rid;
                    497:     } else {
                    498: 	$hash{'ids_'.$idsuri}=''.$rid;
                    499:     }
                    500:     
1.139     foxr      501: 
                    502: 
1.135     raeburn   503:     if ($turi=~/\/(syllabus|aboutme|navmaps|smppg|bulletinboard|viewclasslist)$/) {
1.124     albertel  504: 	$turi.='?register=1';
                    505:     }
                    506:     
1.139     foxr      507: 
                    508:     # resource id lookup:  'src'_resourc-di  => URI decorated with a query
                    509:     # parameter as above if necessary due to the resource type.
                    510:     
1.124     albertel  511:     $hash{'src_'.$rid}=$turi;
1.139     foxr      512: 
                    513:     # Mark the external-ness of the resource:
1.124     albertel  514:     
                    515:     if ($token->[2]->{'external'} eq 'true') {
                    516: 	$hash{'ext_'.$rid}='true:';
                    517:     } else {
                    518: 	$hash{'ext_'.$rid}='false:';
                    519:     }
1.139     foxr      520: 
                    521:     # If the resource is a start/finish resource set those
                    522:     # entries in the has so that navigation knows where everything starts.
                    523:     # TODO?  If there is a malformed sequence that has no start or no finish
                    524:     # resource, should this be detected and errors thrown?  How would such a 
                    525:     # resource come into being other than being manually constructed by a person
                    526:     # and then uploaded?  Could that happen if an author decided a sequence was almost
                    527:     # right edited it by hand and then reuploaded it to 'fix it' but accidently cut the
                    528:     #  start or finish resources?
                    529:     #
                    530:     #  All resourcess also get a type_id => (start | finish | normal)    hash entr.
                    531:     #
1.124     albertel  532:     if ($token->[2]->{'type'}) {
                    533: 	$hash{'type_'.$rid}=$token->[2]->{'type'};
                    534: 	if ($token->[2]->{'type'} eq 'start') {
                    535: 	    $hash{'map_start_'.$uri}="$rid";
                    536: 	}
                    537: 	if ($token->[2]->{'type'} eq 'finish') {
                    538: 	    $hash{'map_finish_'.$uri}="$rid";
                    539: 	}
                    540:     }  else {
                    541: 	$hash{'type_'.$rid}='normal';
                    542:     }
1.139     foxr      543: 
                    544:     # Sequences end pages are constructed entities.  They require that the 
                    545:     # map that defines _them_ be loaded as well into the hash...with this resourcde
                    546:     # as the base of the nesting.
                    547:     # Resources like that are also marked with is_map_id => 1 entries.
                    548:     #
1.124     albertel  549:     
                    550:     if (($turi=~/\.sequence$/) ||
                    551: 	($turi=~/\.page$/)) {
                    552: 	$hash{'is_map_'.$rid}=1;
1.146     raeburn   553: 	&loadmap($turi,$rid,$courseid);
1.124     albertel  554:     } 
                    555:     return $token->[2]->{'id'};
                    556: }
                    557: 
1.139     foxr      558: #-------------------------------------------------------------------- link
                    559: #  Links define how you are allowed to move from one resource to another.
                    560: #  They are the transition edges in the directed graph that a map is.
                    561: #  This sub takes informatino from a <link> tag and constructs the
                    562: #  navigation bits and pieces of a map.  There is no requirement that the
                    563: #  resources that are linke are already defined, however clearly the map is 
                    564: #  badly broken if they are not _eventually_ defined.
                    565: #
                    566: #  Note that links can be unconditional or conditional.
                    567: #
                    568: #  Parameters:
                    569: #     linkpc   - The link counter for this level of map nesting (this is 
                    570: #                reset to zero by loadmap prior to starting to process
                    571: #                links for map).
                    572: #     lpc      - The map level ocounter (how deeply nested this map is in
                    573: #                the hierarchy of maps that are recursively read in.
                    574: #     to       - resource id (within the XML) of the target of the edge.
                    575: #     from     - resource id (within the XML) of the source of the edge.
                    576: #     condition- id of condition associated with the edge (also within the XML).
                    577: #
                    578: 
1.124     albertel  579: sub make_link {
                    580:     my ($linkpc,$lpc,$to,$from,$condition) = @_;
                    581:     
1.139     foxr      582:     #  Compute fully qualified ids for the link, the 
                    583:     # and from/to by prepending lpc.
                    584:     #
                    585: 
1.124     albertel  586:     my $linkid=$lpc.'.'.$linkpc;
                    587:     my $goesto=$lpc.'.'.$to;
                    588:     my $comesfrom=$lpc.'.'.$from;
                    589:     my $undercond=0;
                    590: 
1.139     foxr      591: 
                    592:     # If there is a condition, qualify it with the level counter.
                    593: 
1.124     albertel  594:     if ($condition) {
                    595: 	$undercond=$lpc.'.'.$condition;
                    596:     }
                    597: 
1.139     foxr      598:     # Links are represnted by:
                    599:     #  goesto_.fuullyqualifedlinkid => fully qualified to
                    600:     #  comesfrom.fullyqualifiedlinkid => fully qualified from
                    601:     #  undercond_.fullyqualifiedlinkid => fully qualified condition id.
                    602: 
1.124     albertel  603:     $hash{'goesto_'.$linkid}=$goesto;
                    604:     $hash{'comesfrom_'.$linkid}=$comesfrom;
                    605:     $hash{'undercond_'.$linkid}=$undercond;
                    606: 
1.139     foxr      607:     # In addition:
                    608:     #   to_.fully qualified from => comma separated list of 
                    609:     #   link ids with that from.
                    610:     # Similarly:
                    611:     #   from_.fully qualified to => comma separated list of link ids`
                    612:     #                               with that to.
                    613:     #  That allows us given a resource id to know all edges that go to it
                    614:     #  and leave from it.
                    615:     #
                    616: 
1.124     albertel  617:     if (defined($hash{'to_'.$comesfrom})) {
                    618: 	$hash{'to_'.$comesfrom}.=','.$linkid;
                    619:     } else {
                    620: 	$hash{'to_'.$comesfrom}=''.$linkid;
                    621:     }
                    622:     if (defined($hash{'from_'.$goesto})) {
                    623: 	$hash{'from_'.$goesto}.=','.$linkid;
                    624:     } else {
                    625: 	$hash{'from_'.$goesto}=''.$linkid;
                    626:     }
                    627: }
                    628: 
                    629: # ------------------------------------------------------------------- Condition
1.139     foxr      630: #
                    631: #  Processes <condition> tags, storing sufficient information about them
                    632: #  in the hash so that they can be evaluated and used to conditionalize
                    633: #  what is presented to the student.
                    634: #
                    635: #  these can have the following attributes 
                    636: #
                    637: #    id    = A unique identifier of the condition within the map.
                    638: #
                    639: #    value = Is a perl script-let that, when evaluated in safe space
                    640: #            determines whether or not the condition is true.
                    641: #            Normally this takes the form of a test on an  Apache::lonnet::EXT call
                    642: #            to find the value of variable associated with a resource in the
                    643: #            map identified by a mapalias.
                    644: #            Here's a fragment of XML code that illustrates this:
                    645: #
                    646: #           <param to="5" value="mainproblem" name="parameter_0_mapalias" type="string" />
                    647: #           <resource src="" id="1" type="start" title="Start" />
                    648: #           <resource src="/res/msu/albertel/b_and_c/p1.problem" id="5"  title="p1.problem" />
                    649: #           <condition value="&EXT('user.resource.resource.0.tries','mainproblem')
                    650: #           <2 " id="61" type="stop" />
                    651: #           <link to="5" index="1" from="1" condition="61" />    
                    652: #
                    653: #           In this fragment:
                    654: #             - The param tag establishes an alias to resource id 5 of 'mainproblem'.
                    655: #             - The resource that is the start of the map is identified.
                    656: #             - The resource tag identifies the resource associated with this tag
                    657: #               and gives it the id 5.
                    658: #             - The condition is true if the tries variable associated with mainproblem
                    659: #               is less than 2 (that is the user has had more than 2 tries).
                    660: #               The condition type is a stop condition which inhibits(?) the associated
                    661: #               link if the condition  is false. 
                    662: #             - The link to resource 5 from resource 1 is affected by this condition.    
                    663: #            
                    664: #    type  = Type of the condition. The type determines how the condition affects the
                    665: #            link associated with it and is one of
                    666: #            -  'force'
                    667: #            -  'stop'
                    668: #              anything else including not supplied..which treated as:
                    669: #            - 'normal'.
                    670: #            Presumably maps get created by the resource assembly tool and therefore
                    671: #            illegal type values won't squirm their way into the XML.
                    672: #
                    673: # Side effects:
                    674: #   -  The kind_level-qualified-condition-id hash element is set to 'cond'.
                    675: #   -  The condition text is pushed into the cond array and its element number is
                    676: #      set in the condid_level-qualified-condition-id element of the hash.
                    677: #   - The condition type is colon appneded to the cond array element for this condition.
1.124     albertel  678: sub parse_condition {
                    679:     my ($token,$lpc) = @_;
                    680:     my $rid=$lpc.'.'.$token->[2]->{'id'};
                    681:     
                    682:     $hash{'kind_'.$rid}='cond';
                    683: 
                    684:     my $condition = $token->[2]->{'value'};
                    685:     $condition =~ s/[\n\r]+/ /gs;
                    686:     push(@cond, $condition);
                    687:     $hash{'condid_'.$rid}=$#cond;
                    688:     if ($token->[2]->{'type'}) {
                    689: 	$cond[$#cond].=':'.$token->[2]->{'type'};
                    690:     }  else {
                    691: 	$cond[$#cond].=':normal';
                    692:     }
                    693: }
                    694: 
                    695: # ------------------------------------------------------------------- Parameter
1.138     foxr      696: # Parse a <parameter> tag in the map.
                    697: # Parmameters:
                    698: #    $token Token array for a start tag from HTML::TokeParser
                    699: #           [0] = 'S'
                    700: #           [1] = tagname ("param")
                    701: #           [2] = Hash of {attribute} = values.
                    702: #           [3] = Array of the keys in [2].
                    703: #           [4] = unused.
                    704: #    $lpc   Current map nesting level.a
                    705: #
                    706: #  Typical attributes:
                    707: #     to=n      - Number of the resource the parameter applies to.
                    708: #     type=xx   - Type of parameter value (e.g. string_yesno or int_pos).
                    709: #     name=xxx  - Name ofr parameter (e.g. parameter_randompick or parameter_randomorder).
                    710: #     value=xxx - value of the parameter.
1.124     albertel  711: 
                    712: sub parse_param {
                    713:     my ($token,$lpc) = @_;
1.138     foxr      714:     my $referid=$lpc.'.'.$token->[2]->{'to'}; # Resource param applies to.
                    715:     my $name=$token->[2]->{'name'};	      # Name of parameter
1.124     albertel  716:     my $part;
1.138     foxr      717: 
                    718: 
                    719:     if ($name=~/^parameter_(.*)_/) { 
1.124     albertel  720: 	$part=$1;
                    721:     } else {
                    722: 	$part=0;
                    723:     }
1.138     foxr      724: 
                    725:     # Peel the parameter_ off the parameter name.
                    726: 
1.124     albertel  727:     $name=~s/^.*_([^_]*)$/$1/;
1.138     foxr      728: 
                    729:     # The value is:
                    730:     #   type.part.name.value
                    731: 
1.124     albertel  732:     my $newparam=
                    733: 	&escape($token->[2]->{'type'}).':'.
                    734: 	&escape($part.'.'.$name).'='.
                    735: 	&escape($token->[2]->{'value'});
1.138     foxr      736: 
                    737:     # The hash key is param_resourceid.
                    738:     # Multiple parameters for a single resource are & separated in the hash.
                    739: 
                    740: 
1.124     albertel  741:     if (defined($hash{'param_'.$referid})) {
                    742: 	$hash{'param_'.$referid}.='&'.$newparam;
                    743:     } else {
                    744: 	$hash{'param_'.$referid}=''.$newparam;
                    745:     }
1.138     foxr      746:     #
                    747:     #  These parameters have to do with randomly selecting
                    748:     # resources, therefore a separate hash is also created to 
                    749:     # make it easy to locate them when actually computing the resource set later on
                    750:     # See the code conditionalized by ($randomize) in loadmap().
                    751: 
                    752:     if ($token->[2]->{'name'}=~/^parameter_(0_)*randompick$/) { # Random selection turned on
1.124     albertel  753: 	$randompick{$referid}=$token->[2]->{'value'};
                    754:     }
1.138     foxr      755:     if ($token->[2]->{'name'}=~/^parameter_(0_)*randompickseed$/) { # Randomseed provided.
1.124     albertel  756: 	$randompickseed{$referid}=$token->[2]->{'value'};
                    757:     }
1.138     foxr      758:     if ($token->[2]->{'name'}=~/^parameter_(0_)*randomorder$/) { # Random order turned on.
1.124     albertel  759: 	$randomorder{$referid}=$token->[2]->{'value'};
                    760:     }
1.138     foxr      761: 
                    762:     # These parameters have to do with how the URLs of resources are presented to
                    763:     # course members(?).  encrypturl presents encypted url's while
                    764:     # hiddenresource hides the URL.
                    765:     #
                    766: 
1.124     albertel  767:     if ($token->[2]->{'name'}=~/^parameter_(0_)*encrypturl$/) {
                    768: 	if ($token->[2]->{'value'}=~/^yes$/i) {
                    769: 	    $encurl{$referid}=1;
                    770: 	}
                    771:     }
                    772:     if ($token->[2]->{'name'}=~/^parameter_(0_)*hiddenresource$/) {
                    773: 	if ($token->[2]->{'value'}=~/^yes$/i) {
                    774: 	    $hiddenurl{$referid}=1;
                    775: 	}
                    776:     }
                    777: }
1.140     foxr      778: #
                    779: #  Parse mapalias parameters.
                    780: #  these are tags of the form:
                    781: #  <param to="nn" 
                    782: #         value="some-alias-for-resourceid-nn" 
                    783: #         name="parameter_0_mapalias" 
                    784: #         type="string" />
                    785: #  A map alias is a textual name for a resource:
                    786: #    - The to  attribute identifies the resource (this gets level qualified below)
                    787: #    - The value attributes provides the alias string.
                    788: #    - name must be of the regexp form: /^parameter_(0_)*mapalias$/
                    789: #    - e.g. the string 'parameter_' followed by 0 or more "0_" strings
                    790: #      terminating with the string 'mapalias'.
                    791: #      Examples:
                    792: #         'parameter_mapalias', 'parameter_0_mapalias', parameter_0_0_mapalias'
                    793: #  Invalid to ids are silently ignored.
                    794: #
                    795: #  Parameters:
                    796: #     token - The token array fromthe HMTML::TokeParser
                    797: #     lpc   - The current map level counter.
                    798: #
1.121     albertel  799: sub parse_mapalias_param {
                    800:     my ($token,$lpc) = @_;
1.140     foxr      801: 
                    802:     # Fully qualify the to value and ignore the alias if there is no
                    803:     # corresponding resource.
                    804: 
1.121     albertel  805:     my $referid=$lpc.'.'.$token->[2]->{'to'};
                    806:     return if (!exists($hash{'src_'.$referid}));
                    807: 
1.140     foxr      808:     # If this is a valid mapalias parameter, 
                    809:     # Append the target id to the count_mapalias element for that
                    810:     # alias so that we can detect doubly defined aliases
                    811:     # e.g.:
                    812:     #  <param to="1" value="george" name="parameter_0_mapalias" type="string" />
                    813:     #  <param to="2" value="george" name="parameter_0_mapalias" type="string" />
                    814:     #
                    815:     #  The example above is trivial but the case that's important has to do with
                    816:     #  constructing a map that includes a nested map where the nested map may have
                    817:     #  aliases that conflict with aliases established in the enclosing map.
                    818:     #
                    819:     # ...and create/update the hash mapalias entry to actually store the alias.
                    820:     #
                    821: 
1.121     albertel  822:     if ($token->[2]->{'name'}=~/^parameter_(0_)*mapalias$/) {
1.122     albertel  823: 	&count_mapalias($token->[2]->{'value'},$referid);
1.121     albertel  824: 	$hash{'mapalias_'.$token->[2]->{'value'}}=$referid;
                    825:     }
1.1       www       826: }
                    827: 
1.3       www       828: # --------------------------------------------------------- Simplify expression
                    829: 
1.140     foxr      830: 
                    831: #
                    832: #  Someone should really comment this to describe what it does to what and why.
                    833: #
1.3       www       834: sub simplify {
1.85      albertel  835:     my $expression=shift;
1.101     albertel  836: # (0&1) = 1
1.105     albertel  837:     $expression=~s/\(0\&([_\.\d]+)\)/$1/g;
1.3       www       838: # (8)=8
1.105     albertel  839:     $expression=~s/\(([_\.\d]+)\)/$1/g;
1.3       www       840: # 8&8=8
1.105     albertel  841:     $expression=~s/([^_\.\d])([_\.\d]+)\&\2([^_\.\d])/$1$2$3/g;
1.3       www       842: # 8|8=8
1.141     raeburn   843:     $expression=~s/([^_\.\d])([_\.\d]+)(?:\|\2)+([^_\.\d])/$1$2$3/g;
1.3       www       844: # (5&3)&4=5&3&4
1.105     albertel  845:     $expression=~s/\(([_\.\d]+)((?:\&[_\.\d]+)+)\)\&([_\.\d]+[^_\.\d])/$1$2\&$3/g;
1.3       www       846: # (((5&3)|(4&6)))=((5&3)|(4&6))
1.105     albertel  847:     $expression=~
                    848: 	s/\((\(\([_\.\d]+(?:\&[_\.\d]+)*\)(?:\|\([_\.\d]+(?:\&[_\.\d]+)*\))+\))\)/$1/g;
1.3       www       849: # ((5&3)|(4&6))|(1&2)=(5&3)|(4&6)|(1&2)
1.85      albertel  850:     $expression=~
1.105     albertel  851: 	s/\((\([_\.\d]+(?:\&[_\.\d]+)*\))((?:\|\([_\.\d]+(?:\&[_\.\d]+)*\))+)\)\|(\([_\.\d]+(?:\&[_\.\d]+)*\))/\($1$2\|$3\)/g;
1.85      albertel  852:     return $expression;
1.3       www       853: }
                    854: 
1.2       www       855: # -------------------------------------------------------- Build condition hash
                    856: 
1.140     foxr      857: #
                    858: #  Traces a route recursively through the map after it has been loaded
                    859: #  (I believe this really visits each resourcde that is reachable fromt he
                    860: #  start top node.
                    861: #
                    862: #  - Marks hidden resources as hidden.
                    863: #  - Marks which resource URL's must be encrypted.
                    864: #  - Figures out (if necessary) the first resource in the map.
                    865: #  - Further builds the chunks of the big hash that define how 
                    866: #    conditions work
                    867: #
                    868: #  Note that the tracing strategy won't visit resources that are not linked to
                    869: #  anything or islands in the map (groups of resources that form a path but are not
                    870: #  linked in to the path that can be traced from the start resource...but that's ok
                    871: #  because by definition, those resources are not reachable by users of the course.
                    872: #
                    873: # Parameters:
                    874: #   sofar    - _URI of the prior entry or 0 if this is the top.
                    875: #   rid      - URI of the resource to visit.
                    876: #   beenhere - list of resources (each resource enclosed by &'s) that have
                    877: #              already been visited.
                    878: #   encflag  - If true the resource that resulted in a recursive call to us
                    879: #              has an encoded URL (which means contained resources should too). 
                    880: #   hdnflag  - If true,the resource that resulted in a recursive call to us
                    881: #              was hidden (which means contained resources should be hidden too).
                    882: # Returns
                    883: #    new value indicating how far the map has been traversed (the sofar).
                    884: #
1.2       www       885: sub traceroute {
1.77      www       886:     my ($sofar,$rid,$beenhere,$encflag,$hdnflag)=@_;
1.81      albertel  887:     my $newsofar=$sofar=simplify($sofar);
1.140     foxr      888: 
1.120     albertel  889:     unless ($beenhere=~/\&\Q$rid\E\&/) {
1.85      albertel  890: 	$beenhere.=$rid.'&';  
                    891: 	my ($mapid,$resid)=split(/\./,$rid);
                    892: 	my $symb=&Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},$resid,$hash{'src_'.$rid});
                    893: 	my $hidden=&Apache::lonnet::EXT('resource.0.hiddenresource',$symb);
1.91      albertel  894: 
1.90      albertel  895: 	if ($hdnflag || lc($hidden) eq 'yes') {
                    896: 	    $hiddenurl{$rid}=1;
1.91      albertel  897: 	}
                    898: 	if (!$hdnflag && lc($hidden) eq 'no') {
1.90      albertel  899: 	    delete($hiddenurl{$rid});
                    900: 	}
1.91      albertel  901: 
1.85      albertel  902: 	my $encrypt=&Apache::lonnet::EXT('resource.0.encrypturl',$symb);
                    903: 	if ($encflag || lc($encrypt) eq 'yes') { $encurl{$rid}=1; }
1.140     foxr      904: 
1.116     www       905: 	if (($retfrid eq '') && ($hash{'src_'.$rid})
1.85      albertel  906: 	    && ($hash{'src_'.$rid}!~/\.sequence$/)) {
1.116     www       907: 	    $retfrid=$rid;
1.85      albertel  908: 	}
1.140     foxr      909: 
1.85      albertel  910: 	if (defined($hash{'conditions_'.$rid})) {
                    911: 	    $hash{'conditions_'.$rid}=simplify(
1.103     albertel  912:            '('.$hash{'conditions_'.$rid}.')|('.$sofar.')');
1.85      albertel  913: 	} else {
                    914: 	    $hash{'conditions_'.$rid}=$sofar;
                    915: 	}
1.107     albertel  916: 
                    917: 	# if the expression is just the 0th condition keep it
                    918: 	# otherwise leave a pointer to this condition expression
1.140     foxr      919: 
1.107     albertel  920: 	$newsofar = ($sofar eq '0') ? $sofar : '_'.$rid;
                    921: 
1.140     foxr      922: 	# Recurse if the resource is a map:
                    923: 
1.85      albertel  924: 	if (defined($hash{'is_map_'.$rid})) {
                    925: 	    if (defined($hash{'map_start_'.$hash{'src_'.$rid}})) {
                    926: 		$sofar=$newsofar=
                    927: 		    &traceroute($sofar,
1.126     albertel  928: 				$hash{'map_start_'.$hash{'src_'.$rid}},
                    929: 				$beenhere,
1.85      albertel  930: 				$encflag || $encurl{$rid},
                    931: 				$hdnflag || $hiddenurl{$rid});
                    932: 	    }
                    933: 	}
1.140     foxr      934: 
                    935: 	# Processes  links to this resource:
                    936: 	#  - verify the existence of any conditionals on the link to here.
                    937: 	#  - Recurse to any resources linked to us.
                    938: 	#
1.85      albertel  939: 	if (defined($hash{'to_'.$rid})) {
1.106     albertel  940: 	    foreach my $id (split(/\,/,$hash{'to_'.$rid})) {
1.2       www       941: 		my $further=$sofar;
1.140     foxr      942: 		#
                    943: 		# If there's a condition associated with this link be sure
                    944: 		# it's been defined else that's an error:
                    945: 		#
1.106     albertel  946:                 if ($hash{'undercond_'.$id}) {
                    947: 		    if (defined($hash{'condid_'.$hash{'undercond_'.$id}})) {
1.105     albertel  948: 			$further=simplify('('.'_'.$rid.')&('.
1.106     albertel  949: 					  $hash{'condid_'.$hash{'undercond_'.$id}}.')');
1.85      albertel  950: 		    } else {
1.147     raeburn   951: 			$errtext.= '<br />'.
                    952:                                    &mt('Undefined condition ID: [_1]',
                    953:                                        $hash{'undercond_'.$id});
1.85      albertel  954: 		    }
1.2       www       955:                 }
1.140     foxr      956: 		#  Recurse to resoruces that have to's to us.
1.106     albertel  957:                 $newsofar=&traceroute($further,$hash{'goesto_'.$id},$beenhere,
1.81      albertel  958: 				      $encflag,$hdnflag);
1.85      albertel  959: 	    }
                    960: 	}
1.2       www       961:     }
1.81      albertel  962:     return $newsofar;
1.2       www       963: }
1.1       www       964: 
1.19      www       965: # ------------------------------ Cascading conditions, quick access, parameters
1.4       www       966: 
1.140     foxr      967: #
                    968: #  Seems a rather strangely named sub given what the comment above says it does.
                    969: 
                    970: 
1.4       www       971: sub accinit {
                    972:     my ($uri,$short,$fn)=@_;
                    973:     my %acchash=();
                    974:     my %captured=();
                    975:     my $condcounter=0;
1.5       www       976:     $acchash{'acc.cond.'.$short.'.0'}=0;
1.140     foxr      977: 
                    978:     # This loop is only interested in conditions and 
                    979:     # parameters in the big hash:
                    980: 
1.104     albertel  981:     foreach my $key (keys(%hash)) {
1.140     foxr      982: 
                    983: 	# conditions:
                    984: 
1.104     albertel  985: 	if ($key=~/^conditions/) {
                    986: 	    my $expr=$hash{$key};
1.140     foxr      987: 
1.109     albertel  988: 	    # try to find and factor out common sub-expressions
1.140     foxr      989: 	    # Any subexpression that is found is simplified, removed from
                    990: 	    # the original condition expression and the simplified sub-expression
                    991: 	    # substituted back in to the epxression..I'm not actually convinced this
                    992: 	    # factors anything out...but instead maybe simplifies common factors(?)
                    993: 
1.105     albertel  994: 	    foreach my $sub ($expr=~m/(\(\([_\.\d]+(?:\&[_\.\d]+)+\)(?:\|\([_\.\d]+(?:\&[_\.\d]+)+\))+\))/g) {
1.104     albertel  995: 		my $orig=$sub;
1.109     albertel  996: 
                    997: 		my ($factor) = ($sub=~/\(\(([_\.\d]+\&(:?[_\.\d]+\&)*)(?:[_\.\d]+\&*)+\)(?:\|\(\1(?:[_\.\d]+\&*)+\))+\)/);
                    998: 		next if (!defined($factor));
                    999: 
                   1000: 		$sub=~s/\Q$factor\E//g;
1.85      albertel 1001: 		$sub=~s/^\(/\($factor\(/;
                   1002: 		$sub.=')';
                   1003: 		$sub=simplify($sub);
1.109     albertel 1004: 		$expr=~s/\Q$orig\E/$sub/;
1.85      albertel 1005: 	    }
1.104     albertel 1006: 	    $hash{$key}=$expr;
1.140     foxr     1007: 
                   1008:            # If not yet seen, record in acchash and that we've seen it.
                   1009: 
1.85      albertel 1010: 	    unless (defined($captured{$expr})) {
                   1011: 		$condcounter++;
                   1012: 		$captured{$expr}=$condcounter;
                   1013: 		$acchash{'acc.cond.'.$short.'.'.$condcounter}=$expr;
                   1014: 	    } 
1.140     foxr     1015:         # Parameters:
                   1016: 
1.104     albertel 1017: 	} elsif ($key=~/^param_(\d+)\.(\d+)/) {
1.86      albertel 1018: 	    my $prefix=&Apache::lonnet::encode_symb($hash{'map_id_'.$1},$2,
                   1019: 						    $hash{'src_'.$1.'.'.$2});
1.104     albertel 1020: 	    foreach my $param (split(/\&/,$hash{$key})) {
                   1021: 		my ($typename,$value)=split(/\=/,$param);
1.85      albertel 1022: 		my ($type,$name)=split(/\:/,$typename);
1.114     www      1023: 		$parmhash{$prefix.'.'.&unescape($name)}=
                   1024: 		    &unescape($value);
                   1025: 		$parmhash{$prefix.'.'.&unescape($name).'.type'}=
                   1026: 		    &unescape($type);
1.85      albertel 1027: 	    }
                   1028: 	}
1.26      harris41 1029:     }
1.140     foxr     1030:     # This loop only processes id entries in the big hash.
                   1031: 
1.104     albertel 1032:     foreach my $key (keys(%hash)) {
                   1033: 	if ($key=~/^ids/) {
                   1034: 	    foreach my $resid (split(/\,/,$hash{$key})) {
1.85      albertel 1035: 		my $uri=$hash{'src_'.$resid};
1.100     albertel 1036: 		my ($uripath,$urifile) =
                   1037: 		    &Apache::lonnet::split_uri_for_cond($uri);
1.85      albertel 1038: 		if ($uripath) {
                   1039: 		    my $uricond='0';
                   1040: 		    if (defined($hash{'conditions_'.$resid})) {
                   1041: 			$uricond=$captured{$hash{'conditions_'.$resid}};
                   1042: 		    }
                   1043: 		    if (defined($acchash{'acc.res.'.$short.'.'.$uripath})) {
                   1044: 			if ($acchash{'acc.res.'.$short.'.'.$uripath}=~
                   1045: 			    /(\&\Q$urifile\E\:[^\&]*)/) {
                   1046: 			    my $replace=$1;
                   1047: 			    my $regexp=$replace;
                   1048: 			    #$regexp=~s/\|/\\\|/g;
1.105     albertel 1049: 			    $acchash{'acc.res.'.$short.'.'.$uripath} =~
1.104     albertel 1050: 				s/\Q$regexp\E/$replace\|$uricond/;
1.85      albertel 1051: 			} else {
                   1052: 			    $acchash{'acc.res.'.$short.'.'.$uripath}.=
                   1053: 				$urifile.':'.$uricond.'&';
                   1054: 			}
                   1055: 		    } else {
                   1056: 			$acchash{'acc.res.'.$short.'.'.$uripath}=
                   1057: 			    '&'.$urifile.':'.$uricond.'&';
                   1058: 		    }
                   1059: 		} 
                   1060: 	    }
                   1061: 	}
1.26      harris41 1062:     }
1.24      www      1063:     $acchash{'acc.res.'.$short.'.'}='&:0&';
1.8       www      1064:     my $courseuri=$uri;
                   1065:     $courseuri=~s/^\/res\///;
1.131     raeburn  1066:     my $regexp = 1;
                   1067:     &Apache::lonnet::delenv('(acc\.|httpref\.)',$regexp);
1.128     raeburn  1068:     &Apache::lonnet::appenv(\%acchash);
1.4       www      1069: }
                   1070: 
1.73      www      1071: # ---------------- Selectively delete from randompick maps and hidden url parms
1.29      www      1072: 
1.73      www      1073: sub hiddenurls {
1.31      www      1074:     my $randomoutentry='';
1.29      www      1075:     foreach my $rid (keys %randompick) {
                   1076:         my $rndpick=$randompick{$rid};
                   1077:         my $mpc=$hash{'map_pc_'.$hash{'src_'.$rid}};
                   1078: # ------------------------------------------- put existing resources into array
                   1079:         my @currentrids=();
1.106     albertel 1080:         foreach my $key (sort(keys(%hash))) {
                   1081: 	    if ($key=~/^src_($mpc\.\d+)/) {
1.29      www      1082: 		if ($hash{'src_'.$1}) { push @currentrids, $1; }
                   1083:             }
                   1084:         }
1.50      albertel 1085: 	# rids are number.number and we want to numercially sort on 
                   1086:         # the second number
                   1087: 	@currentrids=sort {
                   1088: 	    my (undef,$aid)=split(/\./,$a);
                   1089: 	    my (undef,$bid)=split(/\./,$b);
                   1090: 	    $aid <=> $bid;
                   1091: 	} @currentrids;
1.29      www      1092:         next if ($#currentrids<$rndpick);
                   1093: # -------------------------------- randomly eliminate the ones that should stay
1.50      albertel 1094: 	my (undef,$id)=split(/\./,$rid);
1.51      www      1095:         if ($randompickseed{$rid}) { $id=$randompickseed{$rid}; }
1.146     raeburn  1096:         my $setcode;
                   1097:         if (defined($randomizationcode{$rid})) {
                   1098:             if ($env{'form.CODE'} eq '') {
                   1099:                 $env{'form.CODE'} = $randomizationcode{$rid};
                   1100:                 $setcode = 1;
                   1101:             }
                   1102:         }
1.50      albertel 1103: 	my $rndseed=&Apache::lonnet::rndseed($id); # use id instead of symb
1.146     raeburn  1104:         if ($setcode) {
                   1105:             undef($env{'form.CODE'});
                   1106:             undef($setcode);
                   1107:         }
1.58      albertel 1108: 	&Apache::lonnet::setup_random_from_rndseed($rndseed);
1.50      albertel 1109: 	my @whichids=&Math::Random::random_permuted_index($#currentrids+1);
                   1110:         for (my $i=1;$i<=$rndpick;$i++) { $currentrids[$whichids[$i]]=''; }
                   1111: 	#&Apache::lonnet::logthis("$id,$rndseed,".join(':',@whichids));
1.29      www      1112: # -------------------------------------------------------- delete the leftovers
                   1113:         for (my $k=0; $k<=$#currentrids; $k++) {
                   1114:             if ($currentrids[$k]) {
                   1115: 		$hash{'randomout_'.$currentrids[$k]}=1;
1.32      www      1116:                 my ($mapid,$resid)=split(/\./,$currentrids[$k]);
                   1117:                 $randomoutentry.='&'.
1.86      albertel 1118: 		    &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},
                   1119: 						 $resid,
                   1120: 						 $hash{'src_'.$currentrids[$k]}
                   1121: 						 ).'&';
1.29      www      1122:             }
                   1123:         }
1.31      www      1124:     }
1.73      www      1125: # ------------------------------ take care of explicitly hidden urls or folders
                   1126:     foreach my $rid (keys %hiddenurl) {
                   1127: 	$hash{'randomout_'.$rid}=1;
                   1128: 	my ($mapid,$resid)=split(/\./,$rid);
                   1129: 	$randomoutentry.='&'.
1.86      albertel 1130: 	    &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},$resid,
                   1131: 					 $hash{'src_'.$rid}).'&';
1.73      www      1132:     }
                   1133: # --------------------------------------- append randomout entry to environment
1.31      www      1134:     if ($randomoutentry) {
1.128     raeburn  1135: 	&Apache::lonnet::appenv({'acc.randomout' => $randomoutentry});
1.29      www      1136:     }
                   1137: }
                   1138: 
1.1       www      1139: # ---------------------------------------------------- Read map and all submaps
                   1140: 
                   1141: sub readmap {
1.85      albertel 1142:     my $short=shift;
                   1143:     $short=~s/^\///;
1.138     foxr     1144: 
                   1145:     # TODO:  Hidden dependency on current user:
                   1146: 
                   1147:     my %cenv=&Apache::lonnet::coursedescription($short,{'freshen_cache'=>1}); 
                   1148: 
1.85      albertel 1149:     my $fn=$cenv{'fn'};
                   1150:     my $uri;
                   1151:     $short=~s/\//\_/g;
                   1152:     unless ($uri=$cenv{'url'}) { 
1.133     raeburn  1153: 	&Apache::lonnet::logthis('<font color="blue">WARNING: '.
1.85      albertel 1154: 				 "Could not load course $short.</font>"); 
1.114     www      1155: 	return ('',&mt('No course data available.'));;
1.85      albertel 1156:     }
                   1157:     @cond=('true:normal');
1.96      albertel 1158: 
1.133     raeburn  1159:     unless (open(LOCKFILE,">$fn.db.lock")) {
1.138     foxr     1160: 	# 
                   1161: 	# Most likely a permissions problem on the lockfile or its directory.
                   1162: 	#
1.133     raeburn  1163:         $retfurl = '';
1.144     raeburn  1164:         return ($retfurl,'<br />'.&mt('Map not loaded - Lock file could not be opened when reading map:').' <tt>'.$fn.'</tt>.');
1.133     raeburn  1165:     }
1.96      albertel 1166:     my $lock=0;
1.132     raeburn  1167:     my $gotstate=0;
1.138     foxr     1168:     
                   1169:     # If we can get the lock without delay any files there are idle
                   1170:     # and from some prior request.  We'll kill them off and regenerate them:
                   1171: 
                   1172:     if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {	
                   1173: 	$lock=1;		# Remember that we hold the lock.
1.132     raeburn  1174:         &unlink_tmpfiles($fn);
1.96      albertel 1175:     }
1.85      albertel 1176:     undef %randompick;
                   1177:     undef %hiddenurl;
                   1178:     undef %encurl;
1.116     www      1179:     $retfrid='';
1.144     raeburn  1180:     $errtext='';
1.138     foxr     1181:     my ($untiedhash,$untiedparmhash,$tiedhash,$tiedparmhash); # More state flags.
                   1182: 
                   1183:     # if we got the lock, regenerate course regnerate empty files and tie them.
                   1184: 
1.132     raeburn  1185:     if ($lock) {
                   1186:         if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_WRCREAT(),0640)) {
                   1187:             $tiedhash = 1;
                   1188:             if (tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_WRCREAT(),0640)) {
                   1189:                 $tiedparmhash = 1;
1.138     foxr     1190:                 $gotstate = &build_tmp_hashes($uri,
                   1191: 					      $fn,
                   1192: 					      $short,
                   1193: 					      \%cenv); # TODO: Need to provide requested user@dom
1.132     raeburn  1194:                 unless ($gotstate) {
                   1195:                     &Apache::lonnet::logthis('Failed to write statemap at first attempt '.$fn.' for '.$uri.'.</font>');
                   1196:                 }
                   1197:                 $untiedparmhash = untie(%parmhash);
                   1198:                 unless ($untiedparmhash) {
                   1199:                     &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1200:                         'Could not untie coursemap parmhash '.$fn.' for '.$uri.'.</font>');
                   1201:                 }
                   1202:             }
                   1203:             $untiedhash = untie(%hash);
                   1204:             unless ($untiedhash) {
                   1205:                 &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1206:                     'Could not untie coursemap hash '.$fn.' for '.$uri.'.</font>');
                   1207:             }
                   1208:         }
1.138     foxr     1209: 	flock(LOCKFILE,LOCK_UN); # RF: this is what I don't get unless there are other
                   1210: 	                         # unlocked places the remainder happens..seems like if we
                   1211:                                  # just kept the lock here the rest of the code would have
                   1212:                                  # been much easier? 
1.132     raeburn  1213:     }
                   1214:     unless ($lock && $tiedhash && $tiedparmhash) { 
1.87      albertel 1215: 	# if we are here it is likely because we are already trying to 
                   1216: 	# initialize the course in another child, busy wait trying to 
                   1217: 	# tie the hashes for the next 90 seconds, if we succeed forward 
                   1218: 	# them on to navmaps, if we fail, throw up the Could not init 
                   1219: 	# course screen
1.138     foxr     1220: 	#
                   1221: 	# RF: I'm not seeing the case where the ties/unties can fail in a way
                   1222: 	#     that can be remedied by this.  Since we owned the lock seems
                   1223: 	#     Tie/untie failures are a result of something like a permissions problem instead?
                   1224: 	#
                   1225: 
                   1226: 	#  In any vent, undo what we did manage to do above first:
1.96      albertel 1227: 	if ($lock) {
                   1228: 	    # Got the lock but not the DB files
                   1229: 	    flock(LOCKFILE,LOCK_UN);
1.132     raeburn  1230:             $lock = 0;
1.96      albertel 1231: 	}
1.132     raeburn  1232:         if ($tiedhash) {
                   1233:             unless($untiedhash) {
                   1234: 	        untie(%hash);
                   1235:             }
                   1236:         }
                   1237:         if ($tiedparmhash) {
                   1238:             unless($untiedparmhash) {
                   1239:                 untie(%parmhash);
                   1240:             }
                   1241:         }
1.138     foxr     1242: 	# Log our failure:
                   1243: 
1.133     raeburn  1244: 	&Apache::lonnet::logthis('<font color="blue">WARNING: '.
1.132     raeburn  1245: 				 "Could not tie coursemap $fn for $uri.</font>");
                   1246:         $tiedhash = '';
                   1247:         $tiedparmhash = '';
1.87      albertel 1248: 	my $i=0;
1.138     foxr     1249: 
                   1250: 	# Keep on retrying the lock for 90 sec until we succeed.
                   1251: 
1.87      albertel 1252: 	while($i<90) {
                   1253: 	    $i++;
                   1254: 	    sleep(1);
1.132     raeburn  1255: 	    if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {
1.138     foxr     1256: 
                   1257: 		# Got the lock, tie the hashes...the assumption in this code is
                   1258: 		# that some other worker thread has created the db files quite recently
                   1259: 		# so no load is needed:
                   1260: 
1.132     raeburn  1261:                 $lock = 1;
                   1262: 		if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_READER(),0640)) {
                   1263:                     $tiedhash = 1;
                   1264: 		    if (tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_READER(),0640)) {
                   1265:                         $tiedparmhash = 1;
                   1266:                         if (-e "$fn.state") {
                   1267: 		            $retfurl='/adm/navmaps';
1.138     foxr     1268: 
                   1269: 			    # BUG BUG: Side effect!
                   1270: 			    # Should conditionalize on something so that we can use this
                   1271: 			    # to load maps for courses that are not current?
                   1272: 			    #
1.132     raeburn  1273: 		            &Apache::lonnet::appenv({"request.course.id"  => $short,
                   1274: 		   			             "request.course.fn"  => $fn,
1.143     raeburn  1275: 					             "request.course.uri" => $uri,
                   1276:                                                      "request.course.tied" => time});
                   1277:                             
1.132     raeburn  1278: 		            $untiedhash = untie(%hash);
                   1279: 		            $untiedparmhash = untie(%parmhash);
                   1280:                             $gotstate = 1;
                   1281: 		            last;
                   1282: 		        }
                   1283:                         $untiedparmhash = untie(%parmhash);
                   1284: 	            }
                   1285: 	            $untiedhash = untie(%hash);
                   1286:                 }
                   1287:             }
1.87      albertel 1288: 	}
1.132     raeburn  1289:         if ($lock) {
                   1290:             flock(LOCKFILE,LOCK_UN);
1.133     raeburn  1291:             $lock = 0;
1.132     raeburn  1292:             if ($tiedparmhash) {
                   1293:                 unless ($untiedparmhash) {
                   1294:                     &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1295:                         'Could not untie coursemap parmhash '.$fn.' for '.$uri.'.</font>');
                   1296:                 }
                   1297:             }
                   1298:             if ($tiedparmhash) {
                   1299:                 unless ($untiedhash) {
                   1300:                     &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1301:                         'Could not untie coursemap hash '.$fn.' for '.$uri.'.</font>');
                   1302:                 }
                   1303:             }
                   1304:         }
                   1305:     }
1.138     foxr     1306:     # I think this branch of code is all about what happens if we just did the stuff above, 
                   1307:     # but found that the  state file did not exist...again if we'd just held the lock
                   1308:     # would that have made this logic simpler..as generating all the files would be
                   1309:     # an atomic operation with respect to the lock.
                   1310:     #
1.132     raeburn  1311:     unless ($gotstate) {
1.133     raeburn  1312:         $lock = 0;
1.132     raeburn  1313:         &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1314:                      'Could not read statemap '.$fn.' for '.$uri.'.</font>');
                   1315:         &unlink_tmpfiles($fn);
1.133     raeburn  1316:         if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {
                   1317:             $lock=1;
                   1318:         }
                   1319:         undef %randompick;
                   1320:         undef %hiddenurl;
                   1321:         undef %encurl;
1.144     raeburn  1322:         $errtext='';
1.133     raeburn  1323:         $retfrid='';
1.138     foxr     1324: 	#
                   1325: 	# Once more through the routine of tying and loading and so on.
                   1326: 	#
1.133     raeburn  1327:         if ($lock) {
                   1328:             if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_WRCREAT(),0640)) {
                   1329:                 if (tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_WRCREAT(),0640)) {
1.138     foxr     1330:                     $gotstate = &build_tmp_hashes($uri,$fn,$short,\%cenv); # TODO: User dependent?
1.133     raeburn  1331:                     unless ($gotstate) {
1.132     raeburn  1332:                         &Apache::lonnet::logthis('<font color="blue">WARNING: '.
1.133     raeburn  1333:                             'Failed to write statemap at second attempt '.$fn.' for '.$uri.'.</font>');
1.132     raeburn  1334:                     }
1.133     raeburn  1335:                     unless (untie(%parmhash)) {
1.132     raeburn  1336:                         &Apache::lonnet::logthis('<font color="blue">WARNING: '.
1.133     raeburn  1337:                             'Could not untie coursemap parmhash '.$fn.'.db for '.$uri.'.</font>');
1.132     raeburn  1338:                     }
1.133     raeburn  1339:                 } else {
                   1340:                     &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1341:                         'Could not tie coursemap '.$fn.'__parms.db for '.$uri.'.</font>');
                   1342:                 }
                   1343:                 unless (untie(%hash)) {
                   1344:                     &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1345:                         'Could not untie coursemap hash '.$fn.'.db for '.$uri.'.</font>');
                   1346:                 }
1.132     raeburn  1347:             } else {
1.133     raeburn  1348:                &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1349:                    'Could not tie coursemap '.$fn.'.db for '.$uri.'.</font>');
1.132     raeburn  1350:             }
1.133     raeburn  1351:             flock(LOCKFILE,LOCK_UN);
                   1352:             $lock = 0;
                   1353:         } else {
1.138     foxr     1354: 	    # Failed to get the immediate lock.
                   1355: 
1.133     raeburn  1356:             &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                   1357:             'Could not obtain lock to tie coursemap hash '.$fn.'.db for '.$uri.'.</font>');
1.132     raeburn  1358:         }
                   1359:     }
1.133     raeburn  1360:     close(LOCKFILE);
1.132     raeburn  1361:     unless (($errtext eq '') || ($env{'request.course.uri'} =~ m{^/uploaded/})) {
                   1362:         &Apache::lonmsg::author_res_msg($env{'request.course.uri'},
1.138     foxr     1363:                                         $errtext); # TODO: User dependent?
1.1       www      1364:     }
1.46      www      1365: # ------------------------------------------------- Check for critical messages
                   1366: 
1.138     foxr     1367: #  Depends on user must parameterize this as well..or separate as this is:
                   1368: #  more part of determining what someone sees on entering a course?
                   1369: 
1.89      albertel 1370:     my @what=&Apache::lonnet::dump('critical',$env{'user.domain'},
                   1371: 				   $env{'user.name'});
1.46      www      1372:     if ($what[0]) {
                   1373: 	if (($what[0] ne 'con_lost') && ($what[0]!~/^error\:/)) {
                   1374: 	    $retfurl='/adm/email?critical=display';
                   1375:         }
                   1376:     }
1.85      albertel 1377:     return ($retfurl,$errtext);
1.1       www      1378: }
1.15      www      1379: 
1.138     foxr     1380: #
                   1381: #  This sub is called when the course hash and the param hash have been tied and
                   1382: #  their lock file is held.
                   1383: #  Parameters:
                   1384: #     $uri      -  URI that identifies the course.
                   1385: #     $fn       -  The base path/filename of the files that make up the context
                   1386: #                  being built.
                   1387: #     $short    -  Short course name.
                   1388: #     $cenvref  -  Reference to the course environment hash returned by 
                   1389: #                  Apache::lonnet::coursedescription
                   1390: #
                   1391: #  Assumptions:
                   1392: #    The globals
                   1393: #    %hash, %paramhash are tied to their gdbm files and we hold the lock on them.
                   1394: #
1.132     raeburn  1395: sub build_tmp_hashes {
                   1396:     my ($uri,$fn,$short,$cenvref) = @_;
1.138     foxr     1397:     
1.132     raeburn  1398:     unless(ref($cenvref) eq 'HASH') {
                   1399:         return;
                   1400:     }
                   1401:     my %cenv = %{$cenvref};
                   1402:     my $gotstate = 0;
1.138     foxr     1403:     %hash=();			# empty the global course and  parameter hashes.
1.132     raeburn  1404:     %parmhash=();
1.138     foxr     1405:     $errtext='';		# No error messages yet.
1.132     raeburn  1406:     $pc=0;
                   1407:     &clear_mapalias_count();
                   1408:     &processversionfile(%cenv);
1.140     foxr     1409: 
                   1410:     # URI Of the map file.
                   1411: 
1.132     raeburn  1412:     my $furi=&Apache::lonnet::clutter($uri);
1.138     foxr     1413:     #
                   1414:     #  the map staring points.
                   1415:     #
1.132     raeburn  1416:     $hash{'src_0.0'}=&versiontrack($furi);
                   1417:     $hash{'title_0.0'}=&Apache::lonnet::metadata($uri,'title');
                   1418:     $hash{'ids_'.$furi}='0.0';
                   1419:     $hash{'is_map_0.0'}=1;
1.140     foxr     1420: 
                   1421:     # Load the map.. note that loadmap may implicitly recurse if the map contains 
                   1422:     # sub-maps.
                   1423: 
                   1424: 
1.146     raeburn  1425:     &loadmap($uri,'0.0',$short);
1.140     foxr     1426: 
                   1427:     #  The code below only executes if there is a starting point for the map>
                   1428:     #  Q/BUG??? If there is no start resource for the map should that be an error?
                   1429:     #
                   1430: 
1.132     raeburn  1431:     if (defined($hash{'map_start_'.$uri})) {
                   1432:         &Apache::lonnet::appenv({"request.course.id"  => $short,
                   1433:                                  "request.course.fn"  => $fn,
1.143     raeburn  1434:                                  "request.course.uri" => $uri,
                   1435:                                  "request.course.tied" => time});
1.132     raeburn  1436:         $env{'request.course.id'}=$short;
                   1437:         &traceroute('0',$hash{'map_start_'.$uri},'&');
                   1438:         &accinit($uri,$short,$fn);
                   1439:         &hiddenurls();
                   1440:     }
                   1441:     $errtext .= &get_mapalias_errors();
                   1442: # ------------------------------------------------------- Put versions into src
                   1443:     foreach my $key (keys(%hash)) {
                   1444:         if ($key=~/^src_/) {
                   1445:             $hash{$key}=&putinversion($hash{$key});
                   1446:         } elsif ($key =~ /^(map_(?:start|finish|pc)_)(.*)/) {
                   1447:             my ($type, $url) = ($1,$2);
                   1448:             my $value = $hash{$key};
                   1449:             $hash{$type.&putinversion($url)}=$value;
                   1450:         }
                   1451:     }
                   1452: # ---------------------------------------------------------------- Encrypt URLs
                   1453:     foreach my $id (keys(%encurl)) {
                   1454: #           $hash{'src_'.$id}=&Apache::lonenc::encrypted($hash{'src_'.$id});
                   1455:         $hash{'encrypted_'.$id}=1;
                   1456:     }
                   1457: # ----------------------------------------------- Close hashes to finally store
                   1458: # --------------------------------- Routine must pass this point, no early outs
                   1459:     $hash{'first_rid'}=$retfrid;
                   1460:     my ($mapid,$resid)=split(/\./,$retfrid);
                   1461:     $hash{'first_mapurl'}=$hash{'map_id_'.$mapid};
                   1462:     my $symb=&Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},$resid,$hash{'src_'.$retfrid});
                   1463:     $retfurl=&add_get_param($hash{'src_'.$retfrid},{ 'symb' => $symb });
                   1464:     if ($hash{'encrypted_'.$retfrid}) {
                   1465:         $retfurl=&Apache::lonenc::encrypted($retfurl,(&Apache::lonnet::allowed('adv') ne 'F'));
                   1466:     }
                   1467:     $hash{'first_url'}=$retfurl;
                   1468: # ---------------------------------------------------- Store away initial state
                   1469:     {
                   1470:         my $cfh;
                   1471:         if (open($cfh,">$fn.state")) {
                   1472:             print $cfh join("\n",@cond);
                   1473:             $gotstate = 1;
                   1474:         } else {
                   1475:             &Apache::lonnet::logthis("<font color=blue>WARNING: ".
                   1476:                                      "Could not write statemap $fn for $uri.</font>");
                   1477:         }
                   1478:     }
                   1479:     return $gotstate;
                   1480: }
                   1481: 
                   1482: sub unlink_tmpfiles {
                   1483:     my ($fn) = @_;
1.138     foxr     1484:     my $file_dir = dirname($fn);
                   1485: 
1.145     raeburn  1486:     if ("$file_dir/" eq LONCAPA::tempdir()) {
1.132     raeburn  1487:         my @files = qw (.db _symb.db .state _parms.db);
                   1488:         foreach my $file (@files) {
                   1489:             if (-e $fn.$file) {
                   1490:                 unless (unlink($fn.$file)) {
                   1491:                     &Apache::lonnet::logthis("<font color=blue>WARNING: ".
                   1492:                                  "Could not unlink ".$fn.$file."</font>");
                   1493:                 }
                   1494:             }
                   1495:         }
                   1496:     }
                   1497:     return;
                   1498: }
                   1499: 
1.15      www      1500: # ------------------------------------------------------- Evaluate state string
                   1501: 
                   1502: sub evalstate {
1.89      albertel 1503:     my $fn=$env{'request.course.fn'}.'.state';
1.80      albertel 1504:     my $state='';
1.15      www      1505:     if (-e $fn) {
1.80      albertel 1506: 	my @conditions=();
                   1507: 	{
1.115     raeburn  1508: 	    open(my $fh,"<$fn");
1.80      albertel 1509: 	    @conditions=<$fh>;
1.115     raeburn  1510:             close($fh);
1.80      albertel 1511: 	}  
                   1512: 	my $safeeval = new Safe;
                   1513: 	my $safehole = new Safe::Hole;
                   1514: 	$safeeval->permit("entereval");
                   1515: 	$safeeval->permit(":base_math");
                   1516: 	$safeeval->deny(":base_io");
                   1517: 	$safehole->wrap(\&Apache::lonnet::EXT,$safeeval,'&EXT');
                   1518: 	foreach my $line (@conditions) {
                   1519: 	    chomp($line);
                   1520: 	    my ($condition,$weight)=split(/\:/,$line);
                   1521: 	    if ($safeeval->reval($condition)) {
                   1522: 		if ($weight eq 'force') {
                   1523: 		    $state.='3';
                   1524: 		} else {
                   1525: 		    $state.='2';
                   1526: 		}
                   1527: 	    } else {
                   1528: 		if ($weight eq 'stop') {
                   1529: 		    $state.='0';
                   1530: 		} else {
                   1531: 		    $state.='1';
                   1532: 		}
                   1533: 	    }
                   1534: 	}
1.15      www      1535:     }
1.128     raeburn  1536:     &Apache::lonnet::appenv({'user.state.'.$env{'request.course.id'} => $state});
1.15      www      1537:     return $state;
                   1538: }
                   1539: 
1.138     foxr     1540: #  This block seems to have code to manage/detect doubly defined
                   1541: #  aliases in maps.
                   1542: 
1.122     albertel 1543: {
                   1544:     my %mapalias_cache;
                   1545:     sub count_mapalias {
                   1546: 	my ($value,$resid) = @_;
                   1547:  	push(@{ $mapalias_cache{$value} }, $resid);
                   1548:     }
                   1549: 
                   1550:     sub get_mapalias_errors {
                   1551: 	my $error_text;
                   1552: 	foreach my $mapalias (sort(keys(%mapalias_cache))) {
                   1553: 	    next if (scalar(@{ $mapalias_cache{$mapalias} } ) == 1);
                   1554: 	    my $count;
                   1555: 	    my $which =
                   1556: 		join('</li><li>', 
                   1557: 		     map {
                   1558: 			 my $id = $_;
                   1559: 			 if (exists($hash{'src_'.$id})) {
                   1560: 			     $count++;
                   1561: 			 }
                   1562: 			 my ($mapid) = split(/\./,$id);
1.147     raeburn  1563:                          &mt('Resource [_1][_2]in Map [_3]',
                   1564: 			     $hash{'title_'.$id},'<br />',
1.122     albertel 1565: 			     $hash{'title_'.$hash{'ids_'.$hash{'map_id_'.$mapid}}});
                   1566: 		     } (@{ $mapalias_cache{$mapalias} }));
                   1567: 	    next if ($count < 2);
                   1568: 	    $error_text .= '<div class="LC_error">'.
                   1569: 		&mt('Error: Found the mapalias "[_1]" defined multiple times.',
                   1570: 		    $mapalias).
                   1571: 		'</div><ul><li>'.$which.'</li></ul>';
                   1572: 	}
                   1573: 	&clear_mapalias_count();
                   1574: 	return $error_text;
                   1575:     }
                   1576:     sub clear_mapalias_count {
                   1577: 	undef(%mapalias_cache);
                   1578:     }
                   1579: }
1.1       www      1580: 1;
                   1581: __END__
                   1582: 
1.26      harris41 1583: =head1 NAME
                   1584: 
                   1585: Apache::lonuserstate - Construct and maintain state and binary representation
                   1586: of course for user
                   1587: 
                   1588: =head1 SYNOPSIS
                   1589: 
                   1590: Invoked by lonroles.pm.
                   1591: 
                   1592: &Apache::lonuserstate::readmap($cdom.'/'.$cnum);
                   1593: 
                   1594: =head1 INTRODUCTION
                   1595: 
                   1596: This module constructs and maintains state and binary representation
                   1597: of course for user.
                   1598: 
                   1599: This is part of the LearningOnline Network with CAPA project
                   1600: described at http://www.lon-capa.org.
                   1601: 
1.129     jms      1602: =head1 SUBROUTINES
1.26      harris41 1603: 
1.129     jms      1604: =over
1.26      harris41 1605: 
1.129     jms      1606: =item loadmap()
1.26      harris41 1607: 
1.129     jms      1608: Loads map from disk
1.26      harris41 1609: 
1.129     jms      1610: =item simplify()
1.26      harris41 1611: 
1.129     jms      1612: Simplify expression
1.26      harris41 1613: 
1.129     jms      1614: =item traceroute()
1.26      harris41 1615: 
1.129     jms      1616: Build condition hash
1.26      harris41 1617: 
1.129     jms      1618: =item accinit()
1.26      harris41 1619: 
1.129     jms      1620: Cascading conditions, quick access, parameters
1.26      harris41 1621: 
1.129     jms      1622: =item readmap()
1.26      harris41 1623: 
1.129     jms      1624: Read map and all submaps
1.1       www      1625: 
1.129     jms      1626: =item evalstate()
1.1       www      1627: 
1.129     jms      1628: Evaluate state string
1.1       www      1629: 
1.26      harris41 1630: =back
1.1       www      1631: 
1.26      harris41 1632: =cut

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