# The LON-CAPA hint handler.
#
# Handles the displaying of hints.
#
# YEAR=2000
# 12/19,12/21 Guy Albertelli
# YEAR=2001
# 1/4,1/5,1/22,2/7,2/19,3/31,4/5,4/10,5/31,6/2 Guy Albertelli
# 8/6 Scott Harrison

package Apache::hinttags; 

use strict;
use Apache::lonnet;
use capa;

# ======================================================================= BEGIN
sub BEGIN {
  &Apache::lonxml::register('Apache::hinttags',('hintgroup','hintpart',
						'numericalhint'));
}

@Apache::hint::which = ();

# ============================================================ Start hint group
sub start_hintgroup {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $skiptoend = '0';
    my $result;
    if ($target eq 'web') {
	my $id = $Apache::inputtags::part;
	my $numtries = $Apache::lonhomework::history{"resource.$id.tries"};
	if ( $numtries eq '') { $numtries = 0; }
	my $hinttries = &Apache::lonnet::EXT("resource.$id.hinttries");
	if ( $hinttries eq '') { $hinttries = 1; }
	&Apache::lonxml::debug("found :$id:$numtries:$hinttries:");
	if ( $numtries < $hinttries ) {
	    $skiptoend = '1';
	} else {
	    if ($target eq 'web') {
		$result = '<table bgcolor="#dddddd"><tr><td>';
	    }
	}
    }
    if ($skiptoend) {
	&Apache::lonxml::get_all_text("/hintgroup",$$parser[$#$parser]);
    }
    @Apache::hint::which = ();
    return $result;
}

# ============================================================== End hint group
sub end_hintgroup {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result;
    if ($target eq 'web') {
	my $id = $Apache::inputtags::part;
	my $numtries=$Apache::lonhomework::history{"resource.$id.tries"};
	if ( $numtries eq '') { $numtries = 0; }
	my $hinttries=&Apache::lonnet::EXT("resource.$id.hinttries");
	if ( $hinttries eq '') { $hinttries = 1; }
	&Apache::lonxml::debug("found :$id:$numtries:$hinttries:");
	if ( $numtries => $hinttries ) {
	    if ($target eq 'web') {$result = '</td></tr></table>';}
	}	
    }
    @Apache::hint::which = '';
    return $result;
}

# ======================================================== Start numerical hint
sub start_numericalhint {
    #do everything in end, so intervening <responseparams> work
    return '';
}

# ========================================================== End numerical hint
sub end_numericalhint {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result;
    if ($target eq 'web') {
	$safeeval->share_from('capa',['&caparesponse_capa_check_answer']);
	my $name = &Apache::lonxml::get_param('name',$parstack,$safeeval);
	my $response = $Apache::lonhomework::history{'resource.'.
		       $Apache::inputtags::part.'.'.
		       $Apache::inputtags::response['-1'].'.submission'};
	&Apache::lonxml::debug("hintgroup is using $response<br />\n");
	my $expression = "&caparesponse_check_list('".$response."','".
  	                 $$parstack[$#$parstack].
	                 ';my $tol="'.$Apache::inputtags::params{'tol'}.'"'.
	                 ';my $sig="'.$Apache::inputtags::params{'sig'}.'"'.
		         "');";
	$result = &Apache::run::run($expression,$safeeval);
	&Apache::lonxml::debug("$expression:result:$result:".
			       $Apache::lonxml::curdepth);
	my ($awards) = split /:/, $result;
	my ($ad) = &Apache::inputtags::finalizeawards(split /,/ , $awards);
	if ($ad eq 'EXACT_ANS' || $ad eq 'APPROX_ANS') {
	    push (@Apache::hint::which,$name); }
	$result = '';
    }
    return $result;
}

# ======================================================= Starting part of hint
# a part shows if it is on, if no specific parts are on, then default shows
sub start_hintpart {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $show ='0';
    if ($target eq 'web') {
	my $on= &Apache::lonxml::get_param('on',$parstack,$safeeval);
	&Apache::lonxml::debug("hintpart sees $on and ,$#Apache::hint::which");
	if ( $on eq 'default' && $#Apache::hint::which == '-1') {
	    $show=1;
	} else {
	    my $which;
	    foreach $which (@Apache::hint::which) {
		if ($which eq $on) { $show = 1; last } }
	}
	if (!$show) {
	    &Apache::lonxml::get_all_text("/hintpart",$$parser[$#$parser]);
	}
    } elsif ($target eq 'grade') {
	&Apache::lonxml::get_all_text("/hintpart",$$parser[$#$parser]);
    }
    return '';
}

# ========================================================= Ending part of hint
sub end_hintpart {
  return '';
}

1;

__END__