# The LearningOnline Network with CAPA
# input  definitons
#
# $Id: inputtags.pm,v 1.197 2006/06/29 22:57:39 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::inputtags;
use HTML::Entities();
use strict;
use Apache::loncommon;
use Apache::lonlocal;
use Apache::lonnet;
use lib '/home/httpd/lib/perl/';
use LONCAPA;
 

BEGIN {
    &Apache::lonxml::register('Apache::inputtags',('hiddenline','textfield','textline'));
}

#   Initializes a set of global variables used during the parse of the problem.
#
#  @Apache::inputtags::input        - List of current input ids.
#  @Apache::inputtags::inputlist    - List of all input ids seen this problem.
#  @Apache::inputtags::response     - List of all current resopnse ids.
#  @Apache::inputtags::responselist - List of all response ids seen this 
#                                       problem.
#  @Apache::inputtags::hint         - List of all hint ids.
#  @Apache::inputtags::hintlist     - List of all hint ids seen this problem.
#  @Apache::inputtags::previous     - List describing if specific responseds
#                                       have been used
#  @Apache::inputtags::previous_version - Submission responses were used in.
#  $Apache::inputtags::part         - Current part id (valid only in 
#                                       <problem>)
#                                     0 if not in a part.
#  @Apache::inputtags::partlist     - List of part ids seen in the current
#                                       <problem>
#  @Apache::inputtags::status       - List of problem  statuses. First 
#                                     element is the status of the <problem>
#                                     the remainder are for individual <part>s.
#  %Apache::inputtags::params       - Hash of defined parameters for the
#                                     current response.
#  @Apache::inputtags::import       - List of all ids for <import> thes get
#                                     join()ed and prepended.
#  @Apache::inputtags::importlist   - List of all import ids seen.
#  $Apache::inputtags::response_with_no_part
#                                   - Flag set true if we have seen a response
#                                     that is not inside a <part>
#  %Apache::inputtags::answertxt    - <*response> tags store correct
#                                     answer strings for display by <textline/>
#                                     in this hash.

sub initialize_inputtags {
    @Apache::inputtags::input=();
    @Apache::inputtags::inputlist=();
    @Apache::inputtags::response=();
    @Apache::inputtags::responselist=();
    @Apache::inputtags::hint=();
    @Apache::inputtags::hintlist=();
    @Apache::inputtags::previous=();
    @Apache::inputtags::previous_version=();
    $Apache::inputtags::part='';
    @Apache::inputtags::partlist=();
    @Apache::inputtags::status=();
    %Apache::inputtags::params=();
    @Apache::inputtags::import=();
    @Apache::inputtags::importlist=();
    $Apache::inputtags::response_with_no_part=0;
    %Apache::inputtags::answertxt=();
}

sub check_for_duplicate_ids {
    my %check;
    foreach my $id (@Apache::inputtags::partlist,
		    @Apache::inputtags::responselist,
		    @Apache::inputtags::hintlist,
		    @Apache::inputtags::importlist) {
	$check{$id}++;
    }
    my @duplicates;
    foreach my $id (sort(keys(%check))) {
	if ($check{$id} > 1) {
	    push(@duplicates,$id);
	}
    }
    if (@duplicates) {
	&Apache::lonxml::error("Duplicated ids found, problem will operate incorrectly. Duplicated ids seen: ",join(', ',@duplicates));
    }
}

sub start_input {
    my ($parstack,$safeeval)=@_;
    my $id = &Apache::lonxml::get_param('id',$parstack,$safeeval);
    if ($id eq '') { $id = $Apache::lonxml::curdepth; }
    push (@Apache::inputtags::input,$id);
    push (@Apache::inputtags::inputlist,$id);
    return $id;
}

sub end_input {
    pop @Apache::inputtags::input;
    return '';
}

sub addchars {
    my ($fieldid,$addchars)=@_;
    my $output='';
    foreach (split(/\,/,$addchars)) {
	$output.='<a href="javascript:void(document.forms.lonhomework.'.
	    $fieldid.'.value+=\''.$_.'\')">'.$_.'</a> ';
    }
    return $output;
}

sub start_textfield {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = "";
    my $id = &start_input($parstack,$safeeval);
    my $resid=$Apache::inputtags::response[-1];
    if ($target eq 'web') {
	$Apache::lonxml::evaluate--;
	if ($Apache::inputtags::status[-1] eq 'CAN_ANSWER') {
	    my $partid=$Apache::inputtags::part;
	    my $oldresponse = &HTML::Entities::encode($Apache::lonhomework::history{"resource.$partid.$resid.submission"},'<>&"');
	    my $cols = &Apache::lonxml::get_param('cols',$parstack,$safeeval);
	    if ( $cols eq '') { $cols = 80; }
	    my $rows = &Apache::lonxml::get_param('rows',$parstack,$safeeval);
	    if ( $rows eq '') { $rows = 16; }
	    my $addchars=&Apache::lonxml::get_param('addchars',$parstack,$safeeval);
	    $result='';
	    if ($addchars) {
		$result.=&addchars('HWVAL_'.$resid,$addchars);
	    }
	    &Apache::lonhtmlcommon::add_htmlareafields('HWVAL_'.$resid);
	    $result.= '<textarea wrap="hard" name="HWVAL_'.$resid.'" id="HWVAL_'.$resid.'" '.
		"rows=\"$rows\" cols=\"$cols\">".$oldresponse;
	    if ($oldresponse ne '') {

		#get rid of any startup text if the user has already responded
		&Apache::lonxml::get_all_text("/textfield",$parser,$style);
	    }
	} else {
	    #right or wrong don't show it
	    #$result='<table border="1"><tr><td><i>'.$oldresponse.'</i></td></tr></table>';
	    $result='';
	    #get rid of any startup text
	    &Apache::lonxml::get_all_text("/textfield",$parser,$style);
	}
    } elsif ($target eq 'grade') {
	my $seedtext=&Apache::lonxml::get_all_text("/textfield",$parser,
						   $style);
	if ($seedtext eq $env{'form.HWVAL_'.$resid}) {
	    # if the seed text is still there it wasn't a real submission
	    $env{'form.HWVAL_'.$resid}='';
	}
    } elsif ($target eq 'edit') {
	$result.=&Apache::edit::tag_start($target,$token);
	$result.=&Apache::edit::text_arg('Rows:','rows',$token,4);
	$result.=&Apache::edit::text_arg('Columns:','cols',$token,4);
	$result.=&Apache::edit::text_arg
	    ('Click-On Texts (comma sep):','addchars',$token,10);
	my $bodytext=&Apache::lonxml::get_all_text("/textfield",$parser,
						   $style);
	$result.=&Apache::edit::editfield($token->[1],$bodytext,'Text you want to appear by default:',80,2);
    } elsif ($target eq 'modified') {
	my $constructtag=&Apache::edit::get_new_args($token,$parstack,
						     $safeeval,'rows','cols',
						     'addchars');
	if ($constructtag) {
	    $result = &Apache::edit::rebuild_tag($token);
	} else {
	    $result=$token->[4];
	}
	$result.=&Apache::edit::modifiedfield("/textfield",$parser);
    } elsif ($target eq 'tex') {
	my $number_of_lines = &Apache::lonxml::get_param('rows',$parstack,$safeeval);
	my $width_of_box = &Apache::lonxml::get_param('cols',$parstack,$safeeval);
	if ($$tagstack[-2] eq 'essayresponse' and $Apache::lonhomework::type eq 'exam') {
	    $result = '\fbox{\fbox{\parbox{\textwidth-5mm}{';
	    for (my $i=0;$i<int $number_of_lines*2;$i++) {$result.='\strut \\\\ ';}
	    $result.='\strut \\\\\strut \\\\\strut \\\\\strut \\\\}}}';
	} else {
	    my $TeXwidth=$width_of_box/80;
	    $result = '\vskip 1 mm \fbox{\fbox{\parbox{'.$TeXwidth.'\textwidth-5mm}{';
	    for (my $i=0;$i<int $number_of_lines*2;$i++) {$result.='\strut \\\\ ';}
	    $result.='}}}\vskip 2 mm ';
	}
    }
    return $result;
}

sub end_textfield {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $result;
    if ($target eq 'web') {
	$Apache::lonxml::evaluate++;
	if ($Apache::inputtags::status[-1] eq 'CAN_ANSWER') {
	    return "</textarea>";
	}
    } elsif ($target eq 'edit') {
	$result=&Apache::edit::end_table();
    }
    &end_input;
    return $result;
}

sub exam_score_line {
    my ($target) = @_;

    my $result;
    if ($target eq 'tex') {
	my $repetition = &Apache::response::repetition();
	$result.='\begin{enumerate}';
	if ($env{'request.state'} eq "construct" ) {$result.='\item[\strut]';}
	foreach my $i (0..$repetition-1) {
	    $result.='\item[\textbf{'.
		($Apache::lonxml::counter+$i).
		'}.]\textit{Leave blank on scoring form}\vskip 0 mm';
	}
	$result.= '\end{enumerate}';
    }

    return $result;
}

sub exam_box {
    my ($target) = @_;
    my $result;

    if ($target eq 'tex') {
	$result .= '\fbox{\fbox{\parbox{\textwidth-5mm}{\strut\\\\\strut\\\\\strut\\\\\strut\\\\}}}';
	$result .= &exam_score_line($target);
    } elsif ($target eq 'web') {
	my $id=$Apache::inputtags::response[-1];
	$result.= '<br /><br />
                   <textarea name="HWVAL_'.$id.'" rows="4" cols="50">
                   </textarea> <br /><br />';
    }
    return $result;
}

sub needs_exam_box {
    my ($tagstack) = @_;
    my @tags = ('formularesponse',
		'stringresponse',
		'reactionresponse',
		'organicresponse',
		);

    foreach my $tag (@tags) {
	if (grep(/\Q$tag\E/,@$tagstack)) {
	    return 1;
	}
    }
    return 0;
}

sub start_textline {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $result = "";
    if ($target eq 'web') {
	$Apache::lonxml::evaluate--;
	my $partid=$Apache::inputtags::part;
	my $id=$Apache::inputtags::response[-1];
	if ($Apache::inputtags::status[-1] eq 'CAN_ANSWER'
	    || ($Apache::inputtags::status[-1] eq 'CANNOT_ANSWER' &&
		$Apache::lonhomework::history{"resource.$partid.solved"} !~ /^correct/	)) {
	    my $size = &Apache::lonxml::get_param('size',$parstack,$safeeval);
	    my $maxlength;
	    if ($size eq '') { $size=20; } else {
		if ($size < 20) { $maxlength=$size; }
	    }
	    my $oldresponse = &HTML::Entities::encode($Apache::lonhomework::history{"resource.$partid.$id.submission"},'<>&"');
	    if ($Apache::lonhomework::type ne 'exam') {
		my $addchars=&Apache::lonxml::get_param('addchars',$parstack,$safeeval);
		$result='';
		if ($addchars) {
		    $result.=&addchars('HWVAL_'.$id,$addchars);
		}
		my $readonly=&Apache::lonxml::get_param('readonly',$parstack,
							$safeeval);
		if (lc($readonly) eq 'yes' 
		    || $Apache::inputtags::status[-1] eq 'CANNOT_ANSWER') {
		    $readonly=' readonly="readonly" ';
		} else {
		    $readonly='';
		}
		my $name = 'HWVAL_'.$id;
		if ($Apache::inputtags::status[-1] eq 'CANNOT_ANSWER') {
		    $name = "none";
		}
		$result.= '<input type="text" '.$readonly.' name="'.$name.'" value="'.
		    $oldresponse.'" size="'.$size.'" maxlength="'.$maxlength.'" />';
	    }
	    if ($Apache::lonhomework::type eq 'exam'
		&& &needs_exam_box($tagstack)) {
		$result.=&exam_box($target);
	    }
	} else {
	    #right or wrong don't show what was last typed in.
	    $result='<b>'.$Apache::inputtags::answertxt{$id}.'</b>';
	    #$result='';
	}
    } elsif ($target eq 'edit') {
	$result=&Apache::edit::tag_start($target,$token);
	$result.=&Apache::edit::text_arg('Size:','size',$token,'5').
	    &Apache::edit::text_arg('Click-On Texts (comma sep):',
				    'addchars',$token,10);
        $result.=&Apache::edit::select_arg('Readonly:','readonly',
					   ['no','yes'],$token);
	$result.=&Apache::edit::end_row();
	$result.=&Apache::edit::end_table();
    } elsif ($target eq 'modified') {
	my $constructtag=&Apache::edit::get_new_args($token,$parstack,
						     $safeeval,'size',
						     'addchars','readonly');
	if ($constructtag) { $result = &Apache::edit::rebuild_tag($token); }
    } elsif ($target eq 'tex' 
	     && $Apache::lonhomework::type ne 'exam') {
	my $size = &Apache::lonxml::get_param('size',$parstack,$safeeval);
	if ($size != 0) {$size=$size*2; $size.=' mm';} else {$size='40 mm';}
	$result='\framebox['.$size.'][s]{\tiny\strut}';

    } elsif ($target eq 'tex' 
	     && $Apache::lonhomework::type eq 'exam'
	     && &needs_exam_box($tagstack)) {
	$result.=&exam_box($target);
    }
    return $result;
}

sub end_textline {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    if    ($target eq 'web') { $Apache::lonxml::evaluate++; }
    elsif ($target eq 'edit') { return ('','no'); }
    return "";
}

sub start_hiddenline {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    my $result = "";
    if ($target eq 'web') {
	$Apache::lonxml::evaluate--;
	if ($Apache::inputtags::status[-1] eq 'CAN_ANSWER') {
	    my $partid=$Apache::inputtags::part;
	    my $id=$Apache::inputtags::response[-1];
	    my $oldresponse = &HTML::Entities::encode($Apache::lonhomework::history{"resource.$partid.$id.submission"},'<>&"');
	    if ($Apache::lonhomework::type ne 'exam') {
		$result= '<input type="hidden" name="HWVAL_'.$id.'" value="'.
		    $oldresponse.'" />';
	    }
	}
    } elsif ($target eq 'edit') {
	$result=&Apache::edit::tag_start($target,$token);
	$result.=&Apache::edit::end_table;
    }

    if ( ($target eq 'web' || $target eq 'tex')
	 && $Apache::lonhomework::type eq 'exam'
	 && &needs_exam_box($tagstack)) {
	$result.=&exam_box($target);
    }
    return $result;
}

sub end_hiddenline {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval)=@_;
    if    ($target eq 'web') { $Apache::lonxml::evaluate++; }
    elsif ($target eq 'edit') { return ('','no'); }
    return "";
}

# $part -> partid
# $id -> responseid
# $uploadefiletypes -> comma seperated list of extensions allowed or * for any
# $which -> 'uploadedonly'  -> only newly uploaded files
#           'portfolioonly' -> only allow files from portfolio
#           'both' -> allow files from either location
# $extratext -> additional text to go between the link and the input box
# returns a table row <tr> 
sub file_selector {
    my ($part,$id,$uploadedfiletypes,$which,$extratext)=@_;
    if (!$uploadedfiletypes) { return ''; }

    my $jspart=$part;
    $jspart=~s/\./_/g;

    my $result;
    
    $result.='<tr><td>';
    if ($uploadedfiletypes ne '*') {
	$result.=
	    &mt('Allowed filetypes: <b>[_1]</b>',$uploadedfiletypes).'<br />';
    }
    if ($which eq 'uploadonly' || $which eq 'both') { 
	$result.=&mt('Submit a file: (only one file can be uploaded)').
	    ' <br /><input type="file" size="50" name="HWFILE'.
	    $jspart.'_'.$id.'" /><br />';
	my $uploadedfile= &HTML::Entities::encode($Apache::lonhomework::history{"resource.$part.$id.uploadedfile"},'<>&"');

	if ($uploadedfile) {
	    my $url=$Apache::lonhomework::history{"resource.$part.$id.uploadedurl"};
	    &Apache::lonxml::extlink($url);
	    &Apache::lonnet::allowuploaded('/adm/essayresponse',$url);
	    my $icon=&Apache::loncommon::icon($url);
	    my $curfile='<a href="'.$url.'"><img src="'.$icon.
		'" border="0" />'.$uploadedfile.'</a>';
	    $result.=&mt('Currently submitted: <tt>[_1]</tt>',$curfile);
	} else {
	    #$result.=&mt('(Hand in a file you have prepared on your computer)');
	}
    }
    if ( $which eq 'both') { 
	$result.='<br />'.'<strong>'.&mt('OR:').'</strong><br />';
    }
    if ($which eq 'portfolioonly' || $which eq 'both') { 
	$result.=$extratext.'<a href='."'".'javascript:void(window.open("/adm/portfolio?mode=selectfile&amp;fieldname=HWPORT'.$jspart.'_'.$id.'","cat","height=600,width=800,scrollbars=1,resizable=1,menubar=2,location=1"))'."'".'>'.
	    &mt('Select Portfolio Files').'</a><br />'.
	    '<input type="text" size="50" name="HWPORT'.$jspart.'_'.$id.'" value="" />'.
	    '<br />';
	if ($Apache::lonhomework::history{"resource.$part.$id.portfiles"}=~/[^\s]/){
	    my (@filelist,@bad_file_list);
	    foreach my $file (split(',',&unescape($Apache::lonhomework::history{"resource.$part.$id.portfiles"}))) {
		my (undef,undef,$domain,$user)=&Apache::lonxml::whichuser();
		my $url="/uploaded/$domain/$user/portfolio$file";
		my $icon=&Apache::loncommon::icon($url);
		push(@filelist,'<a href="'.$url.'"><img src="'.$icon.
		     '" border="0" />'.$file.'</a>');
		if (! &Apache::lonnet::stat_file($url)) {
		    &Apache::lonnet::logthis("bad file is $url");
		    push(@bad_file_list,'<a href="'.$url.'"><img src="'.$icon.
			 '" border="0" />'.$file.'</a>');
		}
	    }
	    $result.=&mt("Portfolio files previously selected: <strong>[_1]</strong>",join(', ',@filelist));
	    if (@bad_file_list) {
		$result.='<br />'.&mt('<span class="LC_error">These file(s) don\'t exist:</span> <span class="LC_filename">[_1]</span>',join(', ',@bad_file_list));
	    }
	}
    }
    $result.='</td></tr>'; 
    return $result;
}

sub checkstatus {
    my ($value,$awardref,$msgref)=@_;
    for (my $i=0;$i<=$#$awardref;$i++) {
	if ($$awardref[$i] eq $value) {
	    return ($$awardref[$i],$$msgref[$i]);
	}
    }
    return(undef,undef);
}

sub valid_award {
    my ($award) =@_;
    foreach my $possibleaward ('EXTRA_ANSWER','MISSING_ANSWER', 'ERROR',
			       'NO_RESPONSE',
			       'TOO_LONG', 'UNIT_INVALID_INSTRUCTOR',
			       'UNIT_INVALID_STUDENT', 'UNIT_IRRECONCIBLE',
			       'UNIT_FAIL', 'NO_UNIT',
			       'UNIT_NOTNEEDED', 'WANTED_NUMERIC',
			       'BAD_FORMULA', 'SIG_FAIL', 'INCORRECT', 
			       'MISORDERED_RANK', 'INVALID_FILETYPE',
			       'DRAFT', 'SUBMITTED', 'ASSIGNED_SCORE',
			       'APPROX_ANS', 'EXACT_ANS','COMMA_FAIL') {
	if ($award eq $possibleaward) { return 1; }
    }
    return 0;
}

sub finalizeawards {
    my ($awardref,$msgref,$nameref,$reverse)=@_;
    my $result=undef;
    my $award;
    my $msg;
    if ($#$awardref == -1) { $result = "NO_RESPONSE"; }
    if ($result eq '' ) {
	my $blankcount;
	foreach $award (@$awardref) {
	    if ($award eq '') {
		$result='MISSING_ANSWER';
		$blankcount++;
	    }
	}
	if ($blankcount == ($#$awardref + 1)) { $result = 'NO_RESPONSE'; }
    }
    if (defined($result)) { return ($result,$msg); }

    # these awards are ordered from most important error through best correct
    
    my @awards = ('EXTRA_ANSWER', 'MISSING_ANSWER', 'ERROR', 'NO_RESPONSE',
		  'TOO_LONG',
		  'UNIT_INVALID_INSTRUCTOR', 'UNIT_INVALID_STUDENT',
		  'UNIT_IRRECONCIBLE', 'UNIT_FAIL', 'NO_UNIT',
		  'UNIT_NOTNEEDED', 'WANTED_NUMERIC', 'BAD_FORMULA',
		  'COMMA_FAIL', 'SIG_FAIL', 'INCORRECT', 'MISORDERED_RANK',
		  'INVALID_FILETYPE', 'DRAFT', 'SUBMITTED', 'ASSIGNED_SCORE',
		  'APPROX_ANS', 'EXACT_ANS');
    if ($reverse) { @awards=reverse(@awards); }
    foreach my $possibleaward (@awards) {
	($result,$msg)=&checkstatus($possibleaward,$awardref,$msgref);
	if (defined($result)) { return ($result,$msg); }
    }
    return ('ERROR',undef);
}

sub decideoutput {
    my ($award,$awarded,$awardmsg,$solved,$previous,$target)=@_;
    my $message='';
    my $button=0;
    my $previousmsg;
    my $bgcolor='orange';
    my $added_computer_text=0;
    my %possiblecolors =
	( 'correct' => '#aaffaa',
	  'charged_try' => '#ffaaaa',
	  'not_charged_try' => '#ffffaa',
	  'no_message' => '#fffff',
	  );

    my $part = $Apache::inputtags::part;
    my $handgrade = 
	('yes' eq lc(&Apache::lonnet::EXT("resource.$part.handgrade")));
    
    my $computer = ($handgrade)? ''
	                       : " ".&mt("Computer's answer now shown above.");
    &Apache::lonxml::debug("handgrade has :$handgrade:");

    if ($previous) { $previousmsg=&mt('You have entered that answer before'); }
    
    if ($solved =~ /^correct/) {
        $bgcolor=$possiblecolors{'correct'};
	$message=&mt('You are correct.');
	if ($awarded < 1 && $awarded > 0) {
	    $message=&mt('You are partially correct.');
	    $bgcolor=$possiblecolors{'not_charged_try'};
	} elsif ($awarded < 1) {
	    $message=&mt('Incorrect.');
	    $bgcolor=$possiblecolors{'charged_try'};
	}
	if ($env{'request.filename'} =~ 
	    m|/res/lib/templates/examupload.problem$|) {
	    $message = &mt("A score has been assigned.");
	    $added_computer_text=1;
	} else {
	    if ($target eq 'tex') {
		$message = '\textbf{'.$message.'}';
	    } else {
		$message = "<b>".$message."</b>";
		$message.= $computer;
	    }
	    $added_computer_text=1;
	    unless ($env{'course.'.
			     $env{'request.course.id'}.
			     '.disable_receipt_display'} eq 'yes') { 
		$message.=(($target eq 'web')?'<br />':' ').
		    &mt('Your receipt is').' '.&Apache::lonnet::receipt($Apache::inputtags::part).
		    (($target eq 'web')?&Apache::loncommon::help_open_topic('Receipt'):'');
	    }
	}
	$button=0;
	$previousmsg='';
    } elsif ($solved =~ /^excused/) {
	if ($target eq 'tex') {
	    $message = ' \textbf{'.&mt('You are excused from the problem.').'} ';
	} else {
	    $message = "<b>".&mt('You are excused from the problem.')."</b>";
	}
	$bgcolor=$possiblecolors{'charged_try'};
	$button=0;
	$previousmsg='';
    } elsif ($award eq 'EXACT_ANS' || $award eq 'APPROX_ANS' ) {
	if ($solved =~ /^incorrect/ || $solved eq '') {
	    $message = &mt("Incorrect").".";
	    $bgcolor=$possiblecolors{'charged_try'};
	    $button=1;
	} else {
	    if ($target eq 'tex') {
		$message = '\textbf{'.&mt('You are correct.').'}';
	    } else {
		$message = "<b>".&mt('You are correct.')."</b>";
		$message.= $computer;
	    }
	    $added_computer_text=1;
	    unless ($env{'course.'.
			     $env{'request.course.id'}.
			     '.disable_receipt_display'} eq 'yes') { 
		$message.=(($target eq 'web')?'<br />':' ').
		    'Your receipt is '.&Apache::lonnet::receipt($Apache::inputtags::part).
		    (($target eq 'web')?&Apache::loncommon::help_open_topic('Receipt'):'');
	    }
	    $bgcolor=$possiblecolors{'correct'};
	    $button=0;
	    $previousmsg='';
	}
    } elsif ($award eq 'NO_RESPONSE') {
	$message = '';
	$bgcolor=$possiblecolors{'no_feedback'};
	$button=1;
    } elsif ($award eq 'EXTRA_ANSWER') {
	$message = &mt('Some extra items were submitted.');
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button = 1;
    } elsif ($award eq 'MISSING_ANSWER') {
	$message = &mt('Some items were not submitted.');
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button = 1;
    } elsif ($award eq 'ERROR') {
	$message = &mt('An error occured while grading your answer.');
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button = 1;
    } elsif ($award eq 'TOO_LONG') {
	$message = &mt("The submitted answer was too long.");
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'WANTED_NUMERIC') {
	$message = &mt("This question expects a numeric answer.");
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'MISORDERED_RANK') {
	$message = &mt('You have provided an invalid ranking');
	if ($target ne 'tex') {
	    $message.=', '.&mt('please refer to').' '.&Apache::loncommon::help_open_topic('Ranking_Problems','help on ranking problems');
	}
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'INVALID_FILETYPE') {
	$message = &mt('Submission won\'t be graded. The type of file submitted is not allowed.');
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'SIG_FAIL') {
	my ($used,$min,$max)=split(':',$awardmsg);
	my $word;
	if ($used < $min) { $word=&mt('more'); }
	if ($used > $max) { $word=&mt('fewer'); }
	$message = &mt("Submission not graded.  Use [_2] digits.",$used,$word);
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'UNIT_INVALID_INSTRUCTOR') {
	$message = &mt('Error in instructor specifed unit. This error has been reported to the instructor.', $awardmsg);
	if ($target ne 'tex') {$message.=&Apache::loncommon::help_open_topic('Physical_Units');} 
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'UNIT_INVALID_STUDENT') {
	$message = &mt('Unable to interpret units. Computer reads units as "[_1]".',&markup_unit($awardmsg,$target));
	if ($target ne 'tex') {$message.=&Apache::loncommon::help_open_topic('Physical_Units');} 
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'UNIT_FAIL' || $award eq 'UNIT_IRRECONCIBLE') {
	$message = &mt('Incompatible units. No conversion found between "[_1]" and the required units.',&markup_unit($awardmsg,$target));
	if ($target ne 'tex') {$message.=&Apache::loncommon::help_open_topic('Physical_Units');} 
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'UNIT_NOTNEEDED') {
	$message = &mt('Only a number required. Computer reads units of "[_1]".',&markup_unit($awardmsg,$target));
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'NO_UNIT') {
	$message = &mt("Units required").'.';
	if ($target ne 'tex') {$message.=&Apache::loncommon::help_open_topic('Physical_Units')};
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'COMMA_FAIL') {
	$message = &mt("Proper comma separation is required").'.';
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'BAD_FORMULA') {
	$message = &mt("Unable to understand formula");
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'INCORRECT') {
	$message = &mt("Incorrect").'.';
	$bgcolor=$possiblecolors{'charged_try'};
	$button=1;
    } elsif ($award eq 'SUBMITTED') {
	$message = &mt("Your submission has been recorded.");
	$bgcolor=$possiblecolors{'correct'};
	$button=1;
    } elsif ($award eq 'DRAFT') {
	$message = &mt("A draft copy has been saved.");
	$bgcolor=$possiblecolors{'not_charged_try'};
	$button=1;
    } elsif ($award eq 'ASSIGNED_SCORE') {
	$message = &mt("A score has been assigned.");
	$bgcolor=$possiblecolors{'correct'};
	$button=0;
    } elsif ($award eq '') {
	if ($handgrade && $Apache::inputtags::status[-1] eq 'SHOW_ANSWER') {
	    $message = &mt("Nothing submitted.");
	    $bgcolor=$possiblecolors{'charged_try'};
	} else {
	    $bgcolor=$possiblecolors{'not_charged_try'};
	}
	$button=1;
    } else {
	$message = &mt("Unknown message").": $award";
	$button=1;
    }
    my (undef,undef,$domain,$user)=&Apache::lonxml::whichuser();
    foreach my $resid(@Apache::inputtags::response){
        &Apache::lonnet::logthis("handback is ".$Apache::lonhomework::history{"resource.$part.$resid.handback"});
        if ($Apache::lonhomework::history{"resource.$part.$resid.handback"}) {
            $message.= '<br /><a href="/uploaded/'."$domain/$user".'/'.$Apache::lonhomework::history{"resource.$part.$resid.handback"}.'">Returned File</a>';
        }
    }

    if (lc($Apache::lonhomework::problemstatus) eq 'no'  && 
	$Apache::inputtags::status[-1] ne 'SHOW_ANSWER') {
	$message = &mt("Answer Submitted: Your final submission will be graded after the due date.");
	$bgcolor=$possiblecolors{'correct'};
	$button=1;
    }
    if ($Apache::inputtags::status[-1] eq 'SHOW_ANSWER' && 
	!$added_computer_text && $target ne 'tex') {
	$message.= $computer;
	$added_computer_text=1;
    }
    return ($button,$bgcolor,$message,$previousmsg);
}

sub markup_unit {
    my ($unit,$target)=@_;
    if ($target eq 'tex') {
	return '\texttt{'.&Apache::lonxml::latex_special_symbols($unit).'}'; 
    } else {
	return "<tt>".$unit."</tt>";
    }
}

sub removealldata {
    my ($id)=@_;
    foreach my $key (keys(%Apache::lonhomework::results)) {
	if (($key =~ /^resource\.\Q$id\E\./) && ($key !~ /\.collaborators$/)) {
	    &Apache::lonxml::debug("Removing $key");
	    delete($Apache::lonhomework::results{$key});
	}
    }
}

sub hidealldata {
    my ($id)=@_;
    foreach my $key (keys(%Apache::lonhomework::results)) {
	if (($key =~ /^resource\.\Q$id\E\./) && ($key !~ /\.collaborators$/)) {
	    &Apache::lonxml::debug("Hidding $key");
	    my $newkey=$key;
	    $newkey=~s/^(resource\.\Q$id\E\.[^\.]+\.)(.*)$/${1}hidden${2}/;
	    $Apache::lonhomework::results{$newkey}=
		$Apache::lonhomework::results{$key};
	    delete($Apache::lonhomework::results{$key});
	}
    }
}

sub setgradedata {
    my ($award,$msg,$id,$previously_used) = @_;
    if ($Apache::lonhomework::scantronmode && 
	&Apache::lonnet::validCODE($env{'form.CODE'})) {
	$Apache::lonhomework::results{"resource.CODE"}=$env{'form.CODE'};
    } elsif ($Apache::lonhomework::scantronmode && 
	     $env{'form.CODE'} eq '' &&
	     $Apache::lonhomework::history{"resource.CODE"} ne '') {
	$Apache::lonhomework::results{"resource.CODE"}='';
    }

    if (!$Apache::lonhomework::scantronmode &&
	$Apache::inputtags::status['-1'] ne 'CAN_ANSWER' &&
	$Apache::inputtags::status['-1'] ne 'CANNOT_ANSWER') {
	$Apache::lonhomework::results{"resource.$id.afterduedate"}=$award;
	return '';
    } elsif ( $Apache::lonhomework::history{"resource.$id.solved"} !~
	      /^correct/ || $Apache::lonhomework::scantronmode ||
	      lc($Apache::lonhomework::problemstatus) eq 'no') {
        # the student doesn't already have it correct,
	# or we are in a mode (scantron orno problem status) where a correct 
        # can become incorrect
	# handle assignment of tries and solved status
	my $solvemsg;
	if ($Apache::lonhomework::scantronmode) {
	    $solvemsg='correct_by_scantron';
	} else {
	    $solvemsg='correct_by_student';
	}
	if ($Apache::lonhomework::history{"resource.$id.afterduedate"}) {
	    $Apache::lonhomework::results{"resource.$id.afterduedate"}='';
	}
	if ( $award eq 'ASSIGNED_SCORE') {
	    $Apache::lonhomework::results{"resource.$id.tries"} =
		$Apache::lonhomework::history{"resource.$id.tries"} + 1;
	    $Apache::lonhomework::results{"resource.$id.solved"} =
		$solvemsg;
	    my $numawards=scalar(@Apache::inputtags::response);
	    $Apache::lonhomework::results{"resource.$id.awarded"} = 0;
	    foreach my $res (@Apache::inputtags::response) {
		$Apache::lonhomework::results{"resource.$id.awarded"}+=
		    $Apache::lonhomework::results{"resource.$id.$res.awarded"};
	    }
	    if ($numawards > 0) {
		$Apache::lonhomework::results{"resource.$id.awarded"}/=
		    $numawards;
	    }
	} elsif ( $award eq 'APPROX_ANS' || $award eq 'EXACT_ANS' ) {
	    $Apache::lonhomework::results{"resource.$id.tries"} =
		$Apache::lonhomework::history{"resource.$id.tries"} + 1;
	    $Apache::lonhomework::results{"resource.$id.solved"} =
		$solvemsg;
	    $Apache::lonhomework::results{"resource.$id.awarded"} = '1';
	} elsif ( $award eq 'INCORRECT' ) {
	    $Apache::lonhomework::results{"resource.$id.tries"} =
		$Apache::lonhomework::history{"resource.$id.tries"} + 1;
	    if (lc($Apache::lonhomework::problemstatus) eq 'no' ||
		$Apache::lonhomework::scantronmode) {
		$Apache::lonhomework::results{"resource.$id.awarded"} = 0;
	    }
	    $Apache::lonhomework::results{"resource.$id.solved"} =
		'incorrect_attempted';
	} elsif ( $award eq 'SUBMITTED' ) {
	    $Apache::lonhomework::results{"resource.$id.tries"} =
		$Apache::lonhomework::history{"resource.$id.tries"} + 1;
	    $Apache::lonhomework::results{"resource.$id.solved"} =
		'ungraded_attempted';
	} elsif ( $award eq 'DRAFT' ) {
	    $Apache::lonhomework::results{"resource.$id.solved"} = '';
	} elsif ( $award eq 'NO_RESPONSE' ) {
	    #no real response so delete any data that got stored
	    &removealldata($id);
	    return '';
	} else {
	    $Apache::lonhomework::results{"resource.$id.solved"} =
		'incorrect_attempted';
	    if (lc($Apache::lonhomework::problemstatus) eq 'no' ||
		$Apache::lonhomework::scantronmode) {
		$Apache::lonhomework::results{"resource.$id.tries"} =
		    $Apache::lonhomework::history{"resource.$id.tries"} + 1;
		$Apache::lonhomework::results{"resource.$id.awarded"} = 0;
	    }
	}
	if (defined($msg)) {
	    $Apache::lonhomework::results{"resource.$id.awardmsg"} = $msg;
	}
	# did either of the overall awards chage? If so ignore the 
	# previous check
	if (($Apache::lonhomework::results{"resource.$id.awarded"} eq
	     $Apache::lonhomework::history{"resource.$id.awarded"}) &&
	    ($Apache::lonhomework::results{"resource.$id.solved"} eq
	     $Apache::lonhomework::history{"resource.$id.solved"})) {
	    # check if this was a previous submission if it was delete the
	    # unneeded data and update the previously_used attribute
	    if ( $previously_used eq 'PREVIOUSLY_USED') {
		if (lc($Apache::lonhomework::problemstatus) ne 'no') {
		    delete($Apache::lonhomework::results{"resource.$id.tries"});
		    $Apache::lonhomework::results{"resource.$id.previous"} = '1';
		}
	    } elsif ( $previously_used eq 'PREVIOUSLY_LAST') {
		#delete all data as they student didn't do anything, but save
		#the list of collaborators.
		&removealldata($id);
		#and since they didn't do anything we were never here
		return '';
	    } else {
		$Apache::lonhomework::results{"resource.$id.previous"} = '0';
	    }
	}
    } elsif ( $Apache::lonhomework::history{"resource.$id.solved"} =~
	      /^correct/ ) {
	#delete all data as they student already has it correct
	&removealldata($id);
	#and since they didn't do anything we were never here
	return '';
    }
    $Apache::lonhomework::results{"resource.$id.award"} = $award;
    if ($award eq 'SUBMITTED') {
	&Apache::response::add_to_gradingqueue();
    }
}

sub grade {
    my ($target) = @_;
    my $id = $Apache::inputtags::part;
    my $response='';
    if ( defined $env{'form.submitted'}) {
	my (@awards,@msgs);
	foreach $response (@Apache::inputtags::response) {
	    &Apache::lonxml::debug("looking for response.$id.$response.awarddetail");
	    my $value=$Apache::lonhomework::results{"resource.$id.$response.awarddetail"};
	    &Apache::lonxml::debug("keeping $value from $response for $id");
	    push (@awards,$value);
	    $value=$Apache::lonhomework::results{"resource.$id.$response.awardmsg"};
	    &Apache::lonxml::debug("got message $value from $response for $id");
	    push (@msgs,$value);
	}
	my ($finalaward,$msg) = &finalizeawards(\@awards,\@msgs);
	my $previously_used;
	if ( $#Apache::inputtags::previous eq $#awards ) {
	    my $match=0;
	    my @matches;
	    foreach my $versionar (@Apache::inputtags::previous_version) {
		foreach my $version (@$versionar) {
		    $matches[$version]++;
		}
	    }
	    foreach my $elem (@matches) {if ($elem eq ($#awards+1)) {$match=1;}}
	    if ($match) {
		$previously_used = 'PREVIOUSLY_LAST';
		foreach my $value (@Apache::inputtags::previous) {
		    if ($value eq 'PREVIOUSLY_USED' ) {
			$previously_used = $value;
			last;
		    }
		}
	    }
	}
	&Apache::lonxml::debug("final award $finalaward, $previously_used, message $msg");
	&setgradedata($finalaward,$msg,$id,$previously_used);
    }
    return '';
}

sub gradestatus {
    my ($id,$target) = @_;
    my $showbutton = 1;
    my $bgcolor = '';
    my $message = '';
    my $latemessage = '';
    my $trystr='';
    my $button='';
    my $previousmsg='';

    my $status = $Apache::inputtags::status['-1'];
    &Apache::lonxml::debug("gradestatus has :$status:");
    if ( $status ne 'CLOSED' 
	 && $status ne 'UNAVAILABLE' 
	 && $status ne 'INVALID_ACCESS' 
	 && $status ne 'NEEDS_CHECKIN' 
	 && $status ne 'NOT_IN_A_SLOT') {  
	my $award = $Apache::lonhomework::history{"resource.$id.award"};
	my $awarded = $Apache::lonhomework::history{"resource.$id.awarded"};
	my $solved = $Apache::lonhomework::history{"resource.$id.solved"};
	my $previous = $Apache::lonhomework::history{"resource.$id.previous"};
	my $awardmsg = $Apache::lonhomework::history{"resource.$id.awardmsg"};
	&Apache::lonxml::debug("Found Award |$award|$solved|$awardmsg");
	if ( $award ne '' || $solved ne '' || $status eq 'SHOW_ANSWER') {
	    &Apache::lonxml::debug('Getting message');
	    ($showbutton,$bgcolor,$message,$previousmsg) =
		&decideoutput($award,$awarded,$awardmsg,$solved,$previous,
			      $target);
	    if ($target eq 'tex') {
		$message='\vskip 2 mm '.$message.' ';
	    } else {
		$message="<td bgcolor=\"$bgcolor\">$message</td>";
		if ($previousmsg) {
		    $previousmsg="<td bgcolor=\"#aaaaff\">$previousmsg</td>";
		}
	    }
	}
	my $tries = $Apache::lonhomework::history{"resource.$id.tries"};
	my $maxtries = &Apache::lonnet::EXT("resource.$id.maxtries");
	&Apache::lonxml::debug("got maxtries of :$maxtries:");
	#if tries are set to negative turn off the Tries/Button and messages
	if (defined($maxtries) && $maxtries < 0) { return ''; }
	if ( $tries eq '' ) { $tries = '0'; }
	if ( $maxtries eq '' ) { $maxtries = '2'; } 
	if ( $maxtries eq 'con_lost' ) { $maxtries = '0'; } 
	my $tries_text=&mt('Tries');
	if ( $Apache::lonhomework::type eq 'survey' ||
	     $Apache::lonhomework::parsing_a_task) {
	    $tries_text=&mt('Submissions');
	}
	if ( $showbutton ) {
	    if ($target eq 'tex') {
		if ($env{'request.state'} ne "construct" && $Apache::lonhomework::type ne 'exam' && $env{'form.suppress_tries'} ne 'yes') {
		    $trystr = ' {\vskip 1 mm \small \textit{'.$tries_text.'} '.$tries.'/'.$maxtries.'} \vskip 2 mm ';
		} else {
		    $trystr = '\vskip 0 mm ';
		}
	    } else {
		$trystr = "<td><nobr>".$tries_text." $tries";
		if ($Apache::lonhomework::parsing_a_task) {
		} elsif($env{'request.state'} ne 'construct') {
		    $trystr.="/$maxtries";
		} else {
		    if (defined($Apache::inputtags::params{'maxtries'})) {
			$trystr.="/".$Apache::inputtags::params{'maxtries'};
		    }
		}
		$trystr.="</nobr></td>";
	    }
	}
	if ( $status eq 'SHOW_ANSWER' || $status eq 'CANNOT_ANSWER') {$showbutton = 0;}
	if ( $showbutton ) { 
	    if ($target ne 'tex') {
		$button = '<input type="submit" name="submit_'.$id.'" value="'.&mt('Submit Answer').'" />';
	    }
	}
	if ($Apache::lonhomework::history{"resource.$id.afterduedate"}) {
	    #last submissions was after due date
	    $latemessage=&mt(' The last submission was after the Due Date ');;
	    if ($target eq 'web') {
		$latemessage='<td bgcolor="#ffaaaa">'.$latemessage.'</td>';
	    }
	}
    }
    my $output= $previousmsg.$latemessage.$message.$trystr;
    if ($output =~ /^\s*$/) {
	return $button;
    } else {
	if ($target eq 'tex') {
	    return $button.' \vskip 0 mm '.$output.' ';
	} else {
	    return '<table><tr><td>'.$button.'</td>'.$output.'</tr></table>';
	}
    }
}
1;
__END__