# The LearningOnline Network with CAPA
# various response type definitons response definition
#
# $Id: response.pm,v 1.152 2006/12/04 21:23:01 albertel Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# LON-CAPA is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#

package Apache::response;
use strict;
use Apache::lonlocal;
use Apache::lonnet;

BEGIN {
    &Apache::lonxml::register('Apache::response',('responseparam','parameter','dataresponse','customresponse','mathresponse'));
}

sub start_response {
    my ($parstack,$safeeval)=@_;
    my $id = &Apache::lonxml::get_id($parstack,$safeeval);
    if ($#Apache::inputtags::import > -1) {
	&Apache::lonxml::debug("Turning :$id: into");
	$id = join('_',@Apache::inputtags::import).'_'.$id;
	&Apache::lonxml::debug("New  :$id:");
    }
    push (@Apache::inputtags::response,$id);
    push (@Apache::inputtags::responselist,$id);
    @Apache::inputtags::inputlist=();
    if ($Apache::inputtags::part eq '' && 
	!$Apache::lonhomework::ignore_response_errors) {
	&Apache::lonxml::error(&HTML::Entities::encode(&mt("Found a <*response> outside of a <part> in a <part>ed problem"),'<>&"'));
    }
    if ($Apache::inputtags::response_with_no_part &&
	$Apache::inputtags::part ne '0') {
	&Apache::lonxml::error(&HTML::Entities::encode(&mt("<*response>s are both inside of <part> and outside of <part>, this is not a valid problem, errors in grading may occur."),'<>&"').'<br />');
    }
    if ($Apache::inputtags::part eq '0') {
	$Apache::inputtags::response_with_no_part=1;
    }
    return $id;
}

sub end_response {
    #pop @Apache::inputtags::response;
    @Apache::inputtags::inputlist=();
    return '';
}

sub start_hintresponse {
    my ($parstack,$safeeval)=@_;
    my $id = &Apache::lonxml::get_id($parstack,$safeeval);
    push (@Apache::inputtags::hint,$id);
    push (@Apache::inputtags::hintlist,$id);
    push (@Apache::inputtags::paramstack,[%Apache::inputtags::params]);
    return $id;
}

sub end_hintresponse {
    pop @Apache::inputtags::hint;
    if (defined($Apache::inputtags::paramstack[-1])) {
	%Apache::inputtags::params=
	    @{ pop(@Apache::inputtags::paramstack) };
    }
    return '';
}

my @randomseeds;
sub pushrandomnumber {
    my $rand_alg=&Apache::lonnet::get_rand_alg();
    if (!$rand_alg || $rand_alg eq '32bit' || $rand_alg eq '64bit' ||
	$rand_alg eq '64bit2') {
	# do nothing
    } else {
	my @seed=&Math::Random::random_get_seed();
	push(@randomseeds,\@seed);
    }
    &Apache::response::setrandomnumber(@_);
}
sub poprandomnumber {
    my $rand_alg=&Apache::lonnet::get_rand_alg();
    if (!$rand_alg || $rand_alg eq '32bit' || $rand_alg eq '64bit' ||
	$rand_alg eq '64bit2') {
	return;
    }
    my $seed=pop(@randomseeds);
    if ($seed) {
	&Math::Random::random_set_seed(@$seed);
    } else {
	&Apache::lonxml::error("Unable to restore random algorithm.");
    }
}

sub setrandomnumber {
    my ($ignore_id2) = @_;
    my $rndseed;
    $rndseed=&Apache::structuretags::setup_rndseed();
    if (!defined($rndseed)) { $rndseed=&Apache::lonnet::rndseed(); }
    &Apache::lonxml::debug("randseed $rndseed");
    #  $rndseed=unpack("%32i",$rndseed);
    my $rand_alg=&Apache::lonnet::get_rand_alg();
    my ($rndmod,$rndmod2);

    my ($id1,$id2,$shift_amt);
    if ($Apache::lonhomework::parsing_a_problem) {
	$id1=$Apache::inputtags::part;
	if (defined($Apache::inputtags::response[-1])) {
	    $id2=$Apache::inputtags::response[-1];
	}
	$shift_amt=scalar(@Apache::inputtags::responselist);
    } elsif ($Apache::lonhomework::parsing_a_task) {
	$id1=&Apache::bridgetask::get_dim_id();
	if (!$ignore_id2 && ref($Apache::bridgetask::instance{$id1})) {
	    $id2=$Apache::bridgetask::instance{$id1}[-1];
	    $shift_amt=scalar(@{$Apache::bridgetask::instance{$id1}});
	} else {
	    $shift_amt=0;
	}
    } 
    &Apache::lonxml::debug("id1: $id1, id2: $id2, shift_amt: $shift_amt");
    if (!$rand_alg || $rand_alg eq '32bit' || $rand_alg eq '64bit' ||
	$rand_alg eq '64bit2') {
	$rndmod=(&Apache::lonnet::numval($id1) << 10);
	if (defined($id2)) { $rndmod+=&Apache::lonnet::numval($id2); }
    } elsif ($rand_alg eq '64bit3') {
	$rndmod=(&Apache::lonnet::numval2($id1) << 10);
	if (defined($id2)) { $rndmod+=&Apache::lonnet::numval2($id2); }
    } elsif ($rand_alg eq '64bit4') {
	my $shift=(4*$shift_amt)%30;
	$rndmod=(&Apache::lonnet::numval3($id1) << (($shift+15)%30));
	if (defined($id2)) {
	    $rndmod+=(&Apache::lonnet::numval3($id2) << $shift );
	}
    } else {
	($rndmod,$rndmod2)=&Apache::lonnet::digest("$id1,$id2");
    }

    if ($rndseed =~/([,:])/) {
	my $char=$1;
	use integer;
	my ($num1,$num2)=split(/\Q$char\E/,$rndseed);
	$num1+=$rndmod;
	$num2+= ((defined($rndmod2)) ? $rndmod2 : $rndmod);
	if($Apache::lonnet::_64bit) { $num1=(($num1<<32)>>32); $num2=(($num2<<32)>>32); }
	$rndseed=$num1.$char.$num2;
    } else {
	$rndseed+=$rndmod;
	if($Apache::lonnet::_64bit) {
	    use integer;
	    $rndseed=(($rndseed<<32)>>32);
	}
    }
    &Apache::lonxml::debug("randseed $rndmod $rndseed");
    &Apache::lonnet::setup_random_from_rndseed($rndseed);
    return '';
}

sub meta_parameter_write {
    my ($name,$type,$default,$display)=@_;
    my $partref=$Apache::inputtags::part;
    my $result='<parameter part="'.$Apache::inputtags::part.'"';
    if (defined($Apache::inputtags::response[-1])) {
	$result.=            ' id="'.$Apache::inputtags::response[-1].'"';
	$partref.='_'.$Apache::inputtags::response[-1];
    }
    $result.=            ' name="'.$name.'"'.
                         ' type="'.$type.'"'.
(defined($default)?' default="'.$default.'"':'').
(defined($display)?' display="'.$display.' [Part: '.$partref.']"':'')
             .'></parameter>'
             ."\n";
    return $result;
}

sub meta_package_write {
    my $name=shift;
    my $result = '<parameter part="'.$Apache::inputtags::part.'"';
    if(defined($Apache::inputtags::response[-1])) {
	$result.= ' id="'.$Apache::inputtags::response[-1].'"';
    }
    $result.=' package="'.$name.'"></parameter>'."\n";
    return $result;
}

sub meta_stores_write {
    my ($name,$type,$display)=@_;
    my $partref=$Apache::inputtags::part;
    my $result = '<stores part="'.$Apache::inputtags::part.'"';
    if (defined($Apache::inputtags::response[-1])) {
	$result.=           ' id="'.$Apache::inputtags::response[-1].'"';
	$partref.='_'.$Apache::inputtags::response[-1];
    }	
    $result.=          ' name="'.$name.'"'.
                       ' type="'.$type.'"'.
	            ' display="'.$display.' [Part: '.$partref.']"'.
		      "></stores>\n";
}

sub mandatory_part_meta {
#
# Autogenerate metadata for mandatory
# input (from RAT or lonparmset) and 
# output (to lonspreadsheet)
# of each part
#
    return
#    &meta_parameter_write('opendate','date_start','',
#                          'Opening Date').
#    &meta_parameter_write('duedate','date_end','',
#                          'Due Date').
#    &meta_parameter_write('answerdate','date_start','',
#                          'Show Answer Date').
#    &meta_parameter_write('weight','int_zeropos','',
#                          'Available Points').
#    &meta_parameter_write('maxtries','int_pos','',
#                          'Maximum Number of Tries').
	&meta_package_write('part').
        &meta_stores_write('solved','string',
			   'Problem Status').
        &meta_stores_write('tries','int_zeropos',
			   'Number of Attempts').
        &meta_stores_write('awarded','float',
			   'Partial Credit Factor');
#
# Note: responseid-specific data 'submission' and 'awarddetail'
# not available to spreadsheet -> skip here
#
}

sub meta_part_order {
    if (@Apache::inputtags::partlist) {
	my @parts=@Apache::inputtags::partlist;
	shift(@parts);
	return '<partorder>'.join(',',@parts).'</partorder>'."\n";
    } else {
	return '<partorder>0</partorder>'."\n";
    }
}

sub meta_response_order {
    if (@Apache::inputtags::responselist) {
	return '<responseorder>'.join(',',@Apache::inputtags::responselist).
	    '</responseorder>'."\n";
    }
}

sub check_for_previous {
    my ($curresponse,$partid,$id) = @_;
    my %previous;
    $previous{'used'} = 0;
    foreach my $key (sort(keys(%Apache::lonhomework::history))) {
	if ($key =~ /resource\.$partid\.$id\.submission$/) {
	    &Apache::lonxml::debug("Trying $key");
	    my $pastresponse=$Apache::lonhomework::history{$key};
	    if ($pastresponse eq $curresponse) {
		$previous{'used'} = 1;
		my $history;
		if ( $key =~ /^(\d+):/ ) {
		    $history=$1;
		    $previous{'award'} = $Apache::lonhomework::history{"$history:resource.$partid.$id.awarddetail"};
		    $previous{'last'}='0';
		    push(@{ $previous{'version'} },$history);
		} else {
		    $previous{'award'} = $Apache::lonhomework::history{"resource.$partid.$id.awarddetail"};
		    $previous{'last'}='1';
		}
		if (! $previous{'award'} ) { $previous{'award'} = 'UNKNOWN';	}
		&Apache::lonxml::debug("got a match :$previous{'award'}:$previous{'used'}:");
	    }
	}
    }
    &Apache::lonhomework::showhash(%previous);
    return %previous;
}

sub handle_previous {
    my ($previous,$ad)=@_;
    if ($$previous{'used'} && ($$previous{'award'} eq $ad) ) {
	if ($$previous{'last'}) {
	    push(@Apache::inputtags::previous,'PREVIOUSLY_LAST');
	    push(@Apache::inputtags::previous_version,$$previous{'version'});
	} elsif ($Apache::lonhomework::type ne 'survey') {
	    push(@Apache::inputtags::previous,'PREVIOUSLY_USED');
	    push(@Apache::inputtags::previous_version,$$previous{'version'});
	}
    }
}

sub view_or_modify {
    my ($symb,$courseid,$domain,$name) = &Apache::lonnet::whichuser();
    my $myself=0;
    if ( ($name eq $env{'user.name'}) && ($domain eq $env{'user.domain'}) ) {
	$myself=1;
    }
    my $vgr=&Apache::lonnet::allowed('vgr',$courseid);
    my $mgr=&Apache::lonnet::allowed('vgr',$courseid);
    if ($mgr) { return "M"; }
    if ($vgr) { return "V"; }
    if ($myself) { return "V"; }
    return '';
}

sub start_dataresponse {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $id = &Apache::response::start_response($parstack,$safeeval);
    my $result;
    if ($target eq 'web') {
	$result = $token->[2]->{'display'}.':';
    } elsif ($target eq 'meta') {
	$result = &Apache::response::meta_stores_write($token->[2]->{'name'},
						       $token->[2]->{'type'},
						       $token->[2]->{'display'});
	$result .= &Apache::response::meta_package_write('dataresponse');
    }
    return $result;
}

sub end_dataresponse {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $result;
    if ( $target eq 'web' ) {
    } elsif ($target eq 'grade' ) {
	if ( defined $env{'form.submitted'}) {
	    my ($symb,$courseid,$domain,$name)=&Apache::lonnet::whichuser();
	    my $allowed=&Apache::lonnet::allowed('mgr',$courseid);
	    if ($allowed) {
		&Apache::response::setup_params('dataresponse',$safeeval);
		my $partid = $Apache::inputtags::part;
		my $id = $Apache::inputtags::response['-1'];
		my $response = $env{'form.HWVAL_'.$id};
		my $name = &Apache::lonxml::get_param('name',$parstack,$safeeval);
		if ( $response =~ /[^\s]/) {
		    $Apache::lonhomework::results{"resource.$partid.$id.$name"}=$response;
		    $Apache::lonhomework::results{"resource.$partid.$id.submission"}=$response;
		    $Apache::lonhomework::results{"resource.$partid.$id.awarddetail"}='SUBMITTED';
		}
	    } else {
		$result='Not Permitted to change values.'
	    }
	}
    }
    &Apache::response::end_response;
    return $result;
}

sub start_customresponse {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $id = &Apache::response::start_response($parstack,$safeeval);
    push(@Apache::lonxml::namespace,'customresponse');
    my $result;
    undef($Apache::response::custom_answer);
    &Apache::lonxml::register('Apache::response',('answer'));
    if ($target eq 'web') {
  	if (  &Apache::response::show_answer() ) {
	    my $answer = &Apache::lonxml::get_param('answerdisplay',$parstack,
						   $safeeval);
	    $Apache::inputtags::answertxt{$id}=[$answer];
	}
    } elsif ($target eq 'edit') {
	$result.=&Apache::edit::tag_start($target,$token);
	$result.=&Apache::edit::text_arg('String to display for answer:',
					 'answerdisplay',$token);
	$result.=&Apache::edit::end_row().&Apache::edit::start_spanning_row();
    } elsif ($target eq 'modified') {
	my $constructtag;
	$constructtag=&Apache::edit::get_new_args($token,$parstack,
						  $safeeval,'answerdisplay');
	if ($constructtag) {
	    $result = &Apache::edit::rebuild_tag($token);
	    $result.=&Apache::edit::handle_insert();
	}
    } elsif ($target eq 'answer' || $target eq 'grade') {
	&Apache::response::reset_params();
    } elsif ($target eq 'meta') {
	$result .= &Apache::response::meta_package_write('customresponse');
    }
    return $result;
}

sub end_customresponse {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $result;
    my $part=$Apache::inputtags::part;
    my $id=$Apache::inputtags::response[-1];
    if ( $target eq 'grade' && &Apache::response::submitted() ) {
	my $response = &Apache::response::getresponse();
	if ($Apache::lonhomework::type eq 'exam' ||
	    &Apache::response::submitted('scantron')) {
	    &Apache::response::scored_response($part,$id);
	} elsif ( $response =~ /[^\s]/ && 
		  $Apache::response::custom_answer_type eq 'loncapa/perl') {
	    if (!$Apache::lonxml::default_homework_loaded) {
		&Apache::lonxml::default_homework_load($safeeval);
	    }
	    my %previous = &Apache::response::check_for_previous($response,
								 $part,$id);
	    $Apache::lonhomework::results{"resource.$part.$id.submission"}=
		$response;
	    my $error;
	    ${$safeeval->varglob('LONCAPA::customresponse_submission')}=
		$response;
	    
	    my $award = &Apache::run::run('{ my $submission=$LONCAPA::customresponse_submission;'.$Apache::response::custom_answer.'}',$safeeval);
	    if (!&Apache::inputtags::valid_award($award)) {
		$error = $award;
		$award = 'ERROR';
	    }
	    &Apache::response::handle_previous(\%previous,$award);
	    $Apache::lonhomework::results{"resource.$part.$id.awarddetail"}=
		$award;
	    if ($error) {
		$Apache::lonhomework::results{"resource.$part.$id.awardmsg"}=
		    $error;
	    }
	}
    } elsif ( $target eq 'answer') {
	$result  = &Apache::response::answer_header('customresponse');
	my $answer = &Apache::lonxml::get_param('answerdisplay',$parstack,
						$safeeval);
	if ($env{'form.answer_output_mode'} ne 'tex') {
	    $answer = '<b>'.$answer.'</b>';
	}
	$result .= &Apache::response::answer_part('customresponse',$answer);
	$result .= &Apache::response::answer_footer('customresponse');
    }
    if ($target eq 'grade' || $target eq 'web' || $target eq 'answer' || 
	$target eq 'tex' || $target eq 'analyze') {
	&Apache::lonxml::increment_counter(&Apache::response::repetition());
    }
    pop(@Apache::lonxml::namespace);
    &Apache::lonxml::deregister('Apache::response',('answer'));
    &Apache::response::end_response();
    return $result;
}


sub start_mathresponse {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $id = &Apache::response::start_response($parstack,$safeeval);
    push(@Apache::lonxml::namespace,'mathresponse');
    my $result;
    undef($Apache::response::custom_answer);
    &Apache::lonxml::register('Apache::response',('answer'));
    if ($target eq 'web') {
  	if (  &Apache::response::show_answer() ) {
	    my $answer = &Apache::lonxml::get_param('answerdisplay',$parstack,
						   $safeeval);
	    $Apache::inputtags::answertxt{$id}=[$answer];
	}
    } elsif ($target eq 'edit') {
	$result.=&Apache::edit::tag_start($target,$token);
	$result.=&Apache::edit::text_arg('String to display for answer:',
					 'answerdisplay',$token);
	$result.=&Apache::edit::select_arg('Algebra System:',
					   'cas',
					   ['maxima'],
					   $token);
	$result.=&Apache::edit::text_arg('Algebra System:',
					 'cas',$token);
	$result.=&Apache::edit::text_arg('Argument Array:',
					 'args',$token);
	$result.=&Apache::edit::end_row().&Apache::edit::start_spanning_row();
    } elsif ($target eq 'modified') {
	my $constructtag;
	$constructtag=&Apache::edit::get_new_args($token,$parstack,
						  $safeeval,'answerdisplay');
	if ($constructtag) {
	    $result = &Apache::edit::rebuild_tag($token);
	    $result.=&Apache::edit::handle_insert();
	}
    } elsif ($target eq 'answer' || $target eq 'grade') {
	&Apache::response::reset_params();
    } elsif ($target eq 'meta') {
	$result .= &Apache::response::meta_package_write('mathresponse');
    }
    return $result;
}

sub end_mathresponse {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $result;
    my $part=$Apache::inputtags::part;
    my $id=$Apache::inputtags::response[-1];
    if ( $target eq 'grade' && &Apache::response::submitted() ) {
	my $response = &Apache::response::getresponse();
	if ( $response =~ /[^\s]/ ) {
	    if (!$Apache::lonxml::default_homework_loaded) {
		&Apache::lonxml::default_homework_load($safeeval);
	    }
	    my %previous = &Apache::response::check_for_previous($response,
								 $part,$id);
	    $Apache::lonhomework::results{"resource.$part.$id.submission"}=
		$response;
	    my $error;
	    ${$safeeval->varglob('LONCAPA::mathresponse_submission')}=
		$response;
	    
	    my $award = &Apache::run::run('{ my $submission=$LONCAPA::mathresponse_submission;'.$Apache::response::custom_answer.'}',$safeeval);
	    if (!&Apache::inputtags::valid_award($award)) {
		$error = $award;
		$award = 'ERROR';
	    }
	    &Apache::response::handle_previous(\%previous,$award);
	    $Apache::lonhomework::results{"resource.$part.$id.awarddetail"}=
		$award;
	    if ($error) {
		$Apache::lonhomework::results{"resource.$part.$id.awardmsg"}=
		    $error;
	    }
	}
    }
    pop(@Apache::lonxml::namespace);
    &Apache::lonxml::deregister('Apache::response',('answer'));
    &Apache::response::end_response();
    return $result;
}


sub start_answer {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $result;
    $Apache::response::custom_answer=
	&Apache::lonxml::get_all_text_unbalanced("/answer",$parser);
    $Apache::response::custom_answer_type=
	lc(&Apache::lonxml::get_param('type',$parstack,$safeeval));
    $Apache::response::custom_answer_type =~ s/\s+//g;
    if ($target eq "edit" ) {
	$result=&Apache::edit::tag_start($target,$token,'Answer algorithm');
	$result.=&Apache::edit::editfield($token->[1],
					  $Apache::response::custom_answer,
					  '',80,4);
    } elsif ( $target eq "modified" ) {
	$result=$token->[4].&Apache::edit::modifiedfield('/answer',$parser);
    }
    return $result;
}

sub end_answer {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    if ($target eq 'edit' ) {
	return &Apache::edit::end_table();
    }
}

sub decide_package {
    my ($tagstack)=@_;
    my $package;
    if ($$tagstack[-1] eq 'parameter') {
	$package='part';
    } else {
	my $i=-1;
	while (defined($$tagstack[$i])) {
	    if ($$tagstack[$i] =~ /(response|hint)$/) {
		$package=$$tagstack[$i];
		last;
	    }
	    $i--;
	}
    }
    return $package;
}

sub start_responseparam {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $result='';
    if ($target eq 'meta') {
	$result = &meta_parameter_write($token->[2]->{'name'},
					$token->[2]->{'type'},
					$token->[2]->{'default'},
					$token->[2]->{'description'});
    } elsif ($target eq 'edit') {
	$result.=&Apache::edit::tag_start($target,$token);
	my $optionlist;
	my $package=&decide_package($tagstack);
	foreach my $key (sort(keys(%Apache::lonnet::packagetab))) {
	    if ($key =~ /^\Q$package\E&(.*)&display$/) {
		$optionlist.='<option value="'.$1.'">'.
		    $Apache::lonnet::packagetab{$key}.'</option>';
	    }
	}
	if (defined($optionlist)) {
	    $result.='Use template: <select name="'.
		&Apache::edit::html_element_name('parameter_package').'">'.
		    '<option value=""></option>'.$optionlist.'</select><br />';
	}
	$result.=&Apache::edit::text_arg('Name:','name',$token).
	    &Apache::edit::text_arg('Type:','type',$token).
		&Apache::edit::text_arg('Description:','description',$token).
		    &Apache::edit::text_arg('Default:','default',$token).
			"</td></tr>";
	$result.=&Apache::edit::end_table;
    } elsif ($target eq 'modified') {
	my $constructtag=&Apache::edit::get_new_args($token,$parstack,
						     $safeeval,'name','type',
						     'description','default');
	my $element=&Apache::edit::html_element_name('parameter_package');
	if (defined($env{"form.$element"}) && $env{"form.$element"} ne '') {
	    my $name=$env{"form.$element"};
	    my $tag=&decide_package($tagstack);
	    $token->[2]->{'name'}=$name;
	    $token->[2]->{'type'}=
		$Apache::lonnet::packagetab{"$tag&$name&type"};
	    $token->[2]->{'description'}=
		$Apache::lonnet::packagetab{"$tag&$name&display"};
	    $token->[2]->{'default'}=
		$Apache::lonnet::packagetab{"$tag&$name&default"};
	    $constructtag=1;
	}
	if ($constructtag) {
	    $result = &Apache::edit::rebuild_tag($token);
	    $result.=&Apache::edit::handle_insert();
	}
    } elsif ($target eq 'grade' || $target eq 'answer' || $target eq 'web' ||
	     $target eq 'tex' || $target eq 'analyze' ) {
	if ($env{'request.state'} eq 'construct') {
	    my $name   =&Apache::lonxml::get_param('name',$parstack,$safeeval);
	    my $default=&Apache::lonxml::get_param('default',$parstack,
						     $safeeval);
	    if ($name) {$Apache::inputtags::params{$name}=$default;}
	}
    }
    return $result;
}

sub end_responseparam {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    if ($target eq 'edit') { return ('','no'); }
    return '';
}

sub start_parameter {
    return &start_responseparam(@_);
}

sub end_parameter {
    return &end_responseparam(@_);
}

sub reset_params {
    %Apache::inputtags::params=();
}

sub setup_params {
    my ($tag,$safeeval) = @_;

    if ($env{'request.state'} eq 'construct') { return; }
    my %paramlist=();
    foreach my $key (keys(%Apache::lonnet::packagetab)) {
	if ($key =~ /^$tag/) {
	    my ($package,$name) = split(/&/,$key);
	    $paramlist{$name}=1;
	}
    }
    foreach my $key (keys(%paramlist)) {
	my $entry= 'resource.'.$Apache::inputtags::part;
	if (defined($Apache::inputtags::response[-1])) {
	    $entry.='_'.$Apache::inputtags::response[-1];
	}
	$entry.='.'.$key;
	&Apache::lonxml::debug("looking for $entry");
	my $value = &Apache::lonnet::EXT("$entry");
	&Apache::lonxml::debug("$key has value :$value:");
	if ($value eq 'con_lost' || $value =~ /^error:/) {
	    &Apache::lonxml::debug("using nothing");
	    $Apache::inputtags::params{$key}='';
	} else {
	    my $string="{return qq\0".$value."\0}";
	    my $newvalue=&Apache::run::run($string,$safeeval,1);
	    if (defined($newvalue)) { $value=$newvalue; }
	    $Apache::inputtags::params{$key}=$value;
	}
    }
}

{
    my @answer_bits;
    my $need_row_start;

sub answer_header {
    my ($type,$increment,$rows) = @_;
    my $result;
    if ($env{'form.answer_output_mode'} eq 'tex') {
	undef(@answer_bits);
	my $bit;
	if ($Apache::lonhomework::type eq 'exam') {
	    $bit = ($Apache::lonxml::counter+$increment).') ';
	} else {
	    $bit .= ' Answer for Part: \verb|'.
		$Apache::inputtags::part.'| ';
	}
	push(@answer_bits,$bit);
    } else {
	my $td = '<td '.(defined($rows)?'rowspan="'.$rows.'"':'').'>';
	$result  = '<table border="1"><tr>';
	if ($Apache::lonhomework::type eq 'exam') {
	    $result .= $td.($Apache::lonxml::counter+$increment). ')</td>';
	} else {
	    $result .= $td.&mt('Answer for Part: [_1]',
			       $Apache::inputtags::part).'</td>';
	}
	$result .= "\n";
	$need_row_start = 0;
    }
    return $result;
}

sub next_answer {
    my ($type) = @_;
    my $result;
    if ($env{'form.answer_output_mode'} eq 'tex') {
	# FIXME ... need to do something with tex mode
    } else {
	$result .= "</tr>";
	$need_row_start = 1;
    }
    return $result;
}

sub answer_part {
    my ($type,$answer,$args) = @_;
    my $result;
    if ($env{'form.answer_output_mode'} eq 'tex') {
	if (!$args->{'no_verbatim'}) {
	    my $to_use='|';
	    foreach my $value (32..126) {
		my $char=pack('c',$value);
		if ($answer !~ /\Q$char\E/) {
		    $to_use=$char;
		    last;
		}
	    }
	    if ($answer ne '') {
		$answer = '\verb'.$to_use.$answer.$to_use;
	    }
	}
	if ($answer ne '') {
	    push(@answer_bits,$answer);
	}
    } else {
	if ($need_row_start) {
	    $result .= '<tr>';
	    $need_row_start = 0;
	}
	$result .= '<td>'.$answer.'</td>';
    }
    return $result;
}

sub answer_footer {
    my ($type) = @_;
    my $result;
    if ($env{'form.answer_output_mode'} eq 'tex') {
	my $columns = scalar(@answer_bits);
	$result  = ' \vskip 0 mm \noindent \begin{tabular}{|'.'c|'x$columns.'}\hline ';
	$result .= join(' & ',@answer_bits);
	$result .= ' \\\\ \\hline \end{tabular} \vskip 0 mm ';
    } else {
	$result = '</tr></table>';
    }
    return $result;
}

}

sub showallfoils {
    if (defined($env{'form.showallfoils'})) {
	my ($symb)=&Apache::lonnet::whichuser();
	if (($env{'request.state'} eq 'construct') || 
	    ($env{'user.adv'} && $symb eq '')      ||
            ($Apache::lonhomework::viewgrades) ) {
	    return 1;
	}
    }
    if ($Apache::lonhomework::type eq 'survey') { return 1; }
    return 0;
}

sub getresponse {
    my ($temp,$resulttype)=@_;
    my $formparm='form.HWVAL_'.$Apache::inputtags::response['-1'];
    my $response;
    if (!defined($temp)) {
	$temp=1;
    } else {
	$formparm.=":$temp";
    }
    my %let_to_num=('A'=>0,'B'=>1,'C'=>2,'D'=>3,'E'=>4,'F'=>5,'G'=>6,'H'=>7,
		    'I'=>8,'J'=>9,'K'=>10,'L'=>11,'M'=>12,'N'=>13,'O'=>14,
		    'P'=>15,'Q'=>16,'R'=>17,'S'=>18,'T'=>19,'U'=>20,'V'=>21,
		    'W'=>22,'X'=>23,'Y'=>24,'Z'=>25);
    if ($env{'form.submitted'} eq 'scantron') {
	my $part  = $Apache::inputtags::part;
	my $id    = $Apache::inputtags::response[-1];
	$response = $env{'scantron.'.($Apache::lonxml::counter+$temp-1).
			 '.answer'};
	# save bubbled letter for later
	$Apache::lonhomework::results{"resource.$part.$id.scantron"}.=
	    $response;
	if ($resulttype ne 'letter') {
	    if ($resulttype eq 'A is 1') {
		$response = $let_to_num{$response}+1;
	    } else {
		$response = $let_to_num{$response};
	    }
	}
    } else {
	$response = $env{$formparm};
    }
    return $response;
}

sub repetition {
    my $id = $Apache::inputtags::part;
    my $weight = &Apache::lonnet::EXT("resource.$id.weight");
    if (!defined($weight) || ($weight eq '')) { $weight=1; }
    my $repetition = int($weight/10);
    if ($weight % 10 != 0) { $repetition++; } 
    return $repetition;
}

sub scored_response {
    my ($part,$id)=@_;
    my $repetition=&repetition();
    my $score=0;
    for (my $i=0;$i<$repetition;$i++) {
	# A is 1, B is 2, etc. (get response return 0-9 and then we add 1)
	my $increase=&Apache::response::getresponse($i+1);
	if ($increase ne '') { $score+=$increase+1; }
    }
    my $weight = &Apache::lonnet::EXT("resource.$part.weight");
    if (!defined($weight) || $weight eq '' || $weight eq 0) { $weight = 1; }
    my $pcr=$score/$weight;
    $Apache::lonhomework::results{"resource.$part.$id.awarded"}=$pcr;
    $Apache::lonhomework::results{"resource.$part.$id.awarddetail"}=
	'ASSIGNED_SCORE';
    return $repetition;
}

sub whichorder {
    my ($max,$randomize,$showall,$hash)=@_;
    #&Apache::lonxml::debug("man $max randomize $randomize");
    if (!defined(@{ $$hash{'names'} })) { return; }
    my @names = @{ $$hash{'names'} };
    my @whichopt =();
    my (%top,@toplist,%bottom,@bottomlist);
    if (!($showall || ($randomize eq 'no'))) {
	my $current=0;
	foreach my $name (@names) {
	    $current++;
	    if ($$hash{"$name.location"} eq 'top') {
		$top{$name}=$current;
	    } elsif ($$hash{"$name.location"} eq 'bottom') {
		$bottom{$name}=$current;
	    }
	}
    }
    my $topcount=0;
    my $bottomcount=0;
    while (((scalar(@whichopt)+$topcount+$bottomcount) < $max || $showall)
	   && ($#names > -1)) {
	#&Apache::lonxml::debug("Have $#whichopt max is $max");
	my $aopt;
	if ($showall || ($randomize eq 'no')) {
	    $aopt=0;
	} else {
	    $aopt=int(&Math::Random::random_uniform() * ($#names+1));
	}
	#&Apache::lonxml::debug("From $#whichopt $max $#names elms, picking $aopt");
	$aopt=splice(@names,$aopt,1);
	#&Apache::lonxml::debug("Picked $aopt");
	if ($top{$aopt}) {
	    $toplist[$top{$aopt}]=$aopt;
	    $topcount++;
	} elsif ($bottom{$aopt}) {
	    $bottomlist[$bottom{$aopt}]=$aopt;
	    $bottomcount++;
	} else {
	    push (@whichopt,$aopt);
	}
    }
    for (my $i=0;$i<=$#toplist;$i++) {
	if ($toplist[$i]) { unshift(@whichopt,$toplist[$i]) }
    }
    for (my $i=0;$i<=$#bottomlist;$i++) {
	if ($bottomlist[$i]) { push(@whichopt,$bottomlist[$i]) }
    }
    return @whichopt;
}

sub show_answer {
    my $part   = $Apache::inputtags::part;
    my $award  = $Apache::lonhomework::history{"resource.$part.solved"};
    my $status = $Apache::inputtags::status[-1];
    return  ( ($award =~ /^correct/
	       && lc($Apache::lonhomework::problemstatus) ne 'no')
	      || $status eq "SHOW_ANSWER");
}

sub analyze_store_foilgroup {
    my ($shown,$attrs)=@_;
    my $part_id="$Apache::inputtags::part.$Apache::inputtags::response[-1]";
    foreach my $name (@{ $Apache::response::foilgroup{'names'} }) {
	if (defined($Apache::lonhomework::analyze{"$part_id.foil.value.$name"})) { next; }
	push (@{ $Apache::lonhomework::analyze{"$part_id.foils"} },$name);
	foreach my $attr (@$attrs) {
	    $Apache::lonhomework::analyze{"$part_id.foil.".$attr.".$name"} =
		$Apache::response::foilgroup{"$name.".$attr};
	}
    }
    push (@{ $Apache::lonhomework::analyze{"$part_id.shown"} }, @{ $shown });
}

sub check_if_computed {
    my ($token,$parstack,$safeeval,$name)=@_;
    my $value = &Apache::lonxml::get_param($name,$parstack,$safeeval);
    if (ref($token->[2]) eq 'HASH' && $value ne $token->[2]{$name}) {
	my $part_id="$Apache::inputtags::part.$Apache::inputtags::response[-1]";
	$Apache::lonhomework::analyze{"$part_id.answercomputed"} = 1;
    }
}

sub pick_foil_for_concept {
    my ($target,$attrs,$hinthash,$parstack,$safeeval)=@_;
    if (not defined(@{ $Apache::response::conceptgroup{'names'} })) { return; }
    my @names = @{ $Apache::response::conceptgroup{'names'} };
    my $pick=int(&Math::Random::random_uniform() * ($#names+1));
    my $name=$names[$pick];
    push @{ $Apache::response::foilgroup{'names'} }, $name;
    foreach my $attr (@$attrs) {
	$Apache::response::foilgroup{"$name.".$attr} =
	    $Apache::response::conceptgroup{"$name.".$attr};
    }
    my $concept = &Apache::lonxml::get_param('concept',$parstack,$safeeval);
    $Apache::response::foilgroup{"$name.concept"} = $concept;
    &Apache::lonxml::debug("Selecting $name in $concept");
    my $part_id="$Apache::inputtags::part.$Apache::inputtags::response[-1]";
    if ($target eq 'analyze') {
	push (@{ $Apache::lonhomework::analyze{"$part_id.concepts"} },
	      $concept);
	$Apache::lonhomework::analyze{"$part_id.concept.$concept"}=
	    $Apache::response::conceptgroup{'names'};
	foreach my $name (@{ $Apache::response::conceptgroup{'names'} }) {
	    push (@{ $Apache::lonhomework::analyze{"$part_id.foils"} },
		  $name);
	    foreach my $attr (@$attrs) {
		$Apache::lonhomework::analyze{"$part_id.foil.$attr.$name"}=
		    $Apache::response::conceptgroup{"$name.$attr"};
	    }
	}
    }
    push(@{ $hinthash->{"$part_id.concepts"} },$concept);
    $hinthash->{"$part_id.concept.$concept"}=
	$Apache::response::conceptgroup{'names'};

}

sub get_response_param {
    my ($id,$name,$default)=@_;
    my $parameter;
    if ($env{'request.state'} eq 'construct' &&
	defined($Apache::inputtags::params{$name})) {
	$parameter=$Apache::inputtags::params{$name};
    } else {
	$parameter=&Apache::lonnet::EXT("resource.$id.$name");
    }
    if (!defined($parameter) ||	$parameter eq '') {
	$parameter = $default;
    }
    return $parameter;
}

sub submitted {
    my ($who)=@_;
    
    # when scatron grading any submission is a submission
    if ($env{'form.submitted'} eq 'scantron') { return 1; }
    # if the caller only cared if this was a scantron submission
    if ($who eq 'scantron') { return 0; }
    # if the Submit Answer button for this particular part was pressed
    my $partid=$Apache::inputtags::part;
    if (defined($env{'form.submit_'.$partid})) { return 1; }
    # Submit All button on a .page was pressed
    if (defined($env{'form.all_submit'})) { return 1; }
    # otherwise no submission occured
    return 0;
}

sub add_to_gradingqueue {
    my ($symb,$courseid,$domain,$name) = &Apache::lonnet::whichuser();
    if (   $courseid eq ''
	|| $symb eq ''
	|| $env{'request.state'} eq 'construct'
	|| $Apache::lonhomework::type ne 'problem') {
	return;
    }

    my %queue_info = ( 'type' => 'problem',
		       'time' => time);

    if (exists($Apache::lonhomework::history{"resource.0.checkedin.slot"})) {
	$queue_info{'slot'}=
	     $Apache::lonhomework::history{"resource.0.checkedin.slot"};
    }

    my $result=&Apache::bridgetask::add_to_queue('gradingqueue',\%queue_info);
    if ($result ne 'ok') {
	&Apache::lonxml::error("add_to_queue said $result");
    }
}

# basically undef and 0 (both false) mean that they still have work to do
# and all true values mean that they can't do any more work
#
# a return of undef means it is unattempted
# a return of 0 means it is attmpted and wrong but still has tries
# a return of 1 means it is marked correct
# a return of 2 means they have exceed maximum number of tries
# a return of 3 means it after the answer date
sub check_status {
    my ($id)=@_;
    if (!defined($id)) { $id=$Apache::inputtags::part; }
    my $curtime=&Apache::lonnet::EXT('system.time');
    my $opendate=&Apache::lonnet::EXT("resource.$id.opendate");
    my $duedate=&Apache::lonnet::EXT("resource.$id.duedate");
    my $answerdate=&Apache::lonnet::EXT("resource.$id.answerdate");
    if ( $opendate && $curtime > $opendate &&
         $duedate && $curtime > $duedate &&
         $answerdate && $curtime > $answerdate) {
        return 3;
    }
    my $status=&Apache::lonnet::EXT("user.resource.resource.$id.solved");
    if ($status =~ /^correct/) { return 1; }
    if (!$status) { return undef; }
    my $maxtries=&Apache::lonnet::EXT("resource.$id.maxtries");
    if ($maxtries eq '') { $maxtries=2; }
    my $curtries=&Apache::lonnet::EXT("user.resource.resource.$id.tries");
    if ($curtries < $maxtries) { return 0; }
    return 2;
}

1;
__END__
 
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