# The LON-CAPA grading handler.
#
# Handles the viewing of grades.
#
# YEAR=2001
# 2/7,2/9,2/13,4/16,4/17,5/1 Guy Albertelli
# 6/8 Gerd Kortemeyer
# 7/26 Guy Albertelli
# 7/27 H.K. Ng
# 7/30 Guy Albertelli
# 8/6 Scott Harrison

package Apache::grades;
use strict;
use Apache::style;
use Apache::lonxml;
use Apache::lonnet;
use Apache::loncommon;
use Apache::lonhomework;
use Apache::Constants qw(:common);

# ======================================================== Get more information
sub moreinfo {
    my ($request,$reason) = @_;
    $request->print("Unable to process request: $reason");
    if ( $Apache::grades::viewgrades eq 'F' ) {
	$request->print('<form action="/adm/grades" method="post">'."\n");
	$request->print('<input type="hidden" name="url" value="'.
			$ENV{'form.url'}.'"></input>'."\n");
	$request->print('<input type="hidden" name="command" value="'.
			$ENV{'form.command'}.'"></input>'."\n");
	$request->print("Student:".
			'<input type="text" name="student" value="'.
			$ENV{'form.student'}.'"></input>'."<br />\n");
	$request->print("Domain:".
			'<input type="text" name="domain" value="'.
			$ENV{'user.domain'}.'"></input>'."<br />\n");
	$request->print('<input type="submit" name="submit" '.
			'value="ReSubmit"></input>'."<br />\n");
	$request->print('</form>');
    }
    return '';
}

# ========================================= Displays the class list of students
sub listStudents {
    my ($request) = shift;
    my ($cdom,$cnum) = split(/_/,$ENV{'request.course.id'});
    my $chome = $ENV{"course.$ENV{'request.course.id'}.home"};
    $request->print ("Found $cdom:$cnum:$chome<br />");
    my (%classlist) = &getclasslist($cdom,$cnum,$chome,'0');
    foreach my $student ( sort(@{ $classlist{'allids'} }) ) {
	my ($sname,$sdom) = split(/:/,$student);
	my $reply = &Apache::lonnet::reply('get:'.$sdom.':'.$sname.
		    ':environment:lastname&generation&firstname&middle'.
		    'name',&Apache::lonnet::homeserver($sname,$sdom));
	print "reply=$reply<br>";
	my (@nameparts) = split /&/,$reply;
#        my $sfullname = $Apache::lonnet::unescape($nameparts[0]);
	if ( $Apache::grades::viewgrades eq 'F' ) {
	    $request->print('<form action="/adm/grades" method="post">'."\n");
	    $request->print("$sname @nameparts\n");
	    $request->print('<input type="hidden" name="url" value="'.
			    $ENV{'form.url'}.'"></input>'."\n");
	    $request->print('<input type="hidden" name="command" value="'.
			    $ENV{'form.command'}.'"></input>'."\n");
	    $request->print('<input type="hidden" name="student" '.
			    'value="'.$sname.'"></input>'."\n");
	    $request->print('<input type="hidden" name="domain" '.
			    'value="'.$sdom.'"></input>'."\n");
	    $request->print('<input type="submit" name="submit" '.
			    'value="View"></input>'."<br />\n");
	    $request->print('</form>');
	}
    }
}

# ========== Finds a user based on a name substring (returns a 2 element array)
#FIXME - needs to handle multiple matches
sub finduser {
    my ($name) = @_;
    my $domain = '';
    if ( $Apache::grades::viewgrades eq 'F' ) {
	#get classlist
	my ($cdom,$cnum) = split(/_/,$ENV{'request.course.id'});
	my $chome = $ENV{"course.$ENV{'request.course.id'}.home"};
	#print "Found $cdom:$cnum:$chome<br />";
	my (%classlist) = &getclasslist($cdom,$cnum,$chome,'0');
	foreach my $student ( sort(@{ $classlist{'allids'} }) ) {
	    my ($posname,$posdomain) = split(/:/,$student);
	    if ($posname =~ $name) { 
		$name = $posname;
		$domain = $posdomain;
		last;
	    }
	}
	return ($name,$domain);
    } else {
	return ($ENV{'user.name'},$ENV{'user.domain'});
    }
}

# ===================================== Gets a class list (returns a hash list)
sub getclasslist {
    my ($coursedomain,$coursenum,$coursehome,$hideexpired) = @_;
    my $classlist = &Apache::lonnet::reply('dump:'.$coursedomain.':'.
					 $coursenum.':classlist',$coursehome);
    my %classlist = ();
    my $now = time;
    foreach my $record (split /&/, $classlist) {
	my ($name,$value)=split(/=/,&Apache::lonnet::unescape($record));
	my ($end,$start)=split(/:/,$value);
	# still a student?
	if (($hideexpired) && ($end) && ($end < $now)) {
	    print "Skipping:$name:$end:$now<br />\n";
	    next;
	}
	print "record=$record<br>";
	push( @{ $classlist{'allids'} }, $name); 
    }
    return (%classlist);
}

# ============================== Get parts of a stored value (returns an array)
sub getpartlist {
    my ($url) = @_;
    my @parts =();
    my (@metakeys) = split(/,/,&Apache::lonnet::metadata($url,'keys'));
    foreach my $key (@metakeys) {
	if ( $key =~ m/stores_([0-9]+)_.*/ ) {
	    push(@parts,$key);
	}
    }
    return @parts;
}

# =================================== Displays student grade (returns a string)
sub viewstudentgrade {
    my ($url,$symb,$courseid,$student,@parts) = @_;
    my $result = '';
    my $cellclr = '"#ffffdd"';
    my ($stuname,$domain) = split(/:/,$student);
    my %record = &Apache::lonnet::restore($symb,$courseid,$domain,$stuname);
    $result .= "<tr><td bgcolor=$cellclr>$stuname</td><td bgcolor=".
	       "\"$cellclr\" align=\"middle\">$domain</td>\n";
    foreach my $part (@parts) {
	my ($temp,$part,$type)=split(/_/,$part);
	#print "resource.$part.$type = ".$record{"resource.$part.$type"}." <br />\n";
	if ($type eq 'awarded') {
	    my $score = $record{"resource.$part.$type"};
	    $result .= "<td bgcolor=$cellclr align=\"middle\">".
		       "<input type=\"text\" name=".
		       "\"GRADE.$student.$part.$type\" ".
		       "value=\"$score\" size=\"4\" /></td>\n";
	} elsif ($type eq 'tries') {
	    my $score = $record{"resource.$part.$type"};
	    $result .= "<td bgcolor=$cellclr align=\"middle\"><input ".
		       "type=\"text\" name=\"GRADE.$student.$part.".
 		       "$type\" value=\"$score\" size=\"4\" /></td>\n";
	} elsif ($type eq 'solved') {
	    my $score = $record{"resource.$part.$type"};
	    $result .= "<td bgcolor=\"$cellclr\" align=\"middle\">".
		       "<select name=\"GRADE.$student.$part.$type\">\n";
	    if ($score =~ /^correct/) {
		$result .= "<option selected=\"on\">correct</option>".
		           "\n<option>incorrect</option>\n<option>".
			   "excused</option>\n<option>ungraded".
			   "</option>\n<option>nothing</option>\n";
	    } elsif ($score =~ /^incorrect/) {
		$result .= "<option>correct</option>\n<option ".
		           "selected=\"on\">incorrect</option>\n".
			   "<option>excused</option>\n<option>".
			   "ungraded</option>\n<option>nothing</option>\n";
	    } elsif ($score eq '') {
		$result .= "<option>correct</option>\n<option> ".
		           "incorrect</option>\n<option>excused".
                           "</option>\n<option>ungraded</option>\n".
			   "<option selected=\"on\">nothing</option>\n";
	    } elsif ($score =~ /^excused/) {
		$result .= "<option>correct</option>\n<option>".
                           "incorrect</option>\n<option selected=".
                           "\"on\">excused</option>\n<option>".
			   "ungraded</option>\n<option>nothing</option>\n";
	    } elsif ($score =~ /^ungraded/) {
		$result .= "<option>correct</option>\n<option>".
		           "incorrect</option>\n<option>excused".
                           "</option>\n<option selected=\"on\">".
			   "ungraded</option>\n<option>nothing</option>\n";
	    }
	    $result .= "</select></td>\n";
	}
    }
    $result .= '</tr>';
    return $result;
}

# ========================================================== Sets student grade
#FIXME need to look at the meatdata <stores> spec
# on what type of data to accept and provide an
#interface based on that, also do that to above function.
sub setstudentgrade {
    my ($url,$symb,$courseid,$student,@parts) = @_;
    my $result ='';
    my ($stuname,$domain) = split(/:/,$student);
    my %record=&Apache::lonnet::restore($symb,$courseid,$domain,$stuname);
    my %newrecord;
    foreach my $part (@parts) {
	my ($temp,$part,$type) = split(/_/,$part);
	my $oldscore = $record{"resource.$part.$type"};
	my $newscore = $ENV{"form.GRADE.$student.$part.$type"};
	if ($type eq 'solved') {
	    my $update = 0;
	    if ($newscore eq 'nothing' ) {
		if ($oldscore ne '') {
		    $update = 1;
		    $newscore = '';
		}
	    } elsif ($oldscore !~ m/^$newscore/) {
		$update=1;
		$result.="Updating $stuname to $newscore<br />\n";
		if ($newscore eq 'correct') { 
		    $newscore = 'correct_by_override'; }
		if ($newscore eq 'incorrect') {
		    $newscore = 'incorrect_by_override'; }
		if ($newscore eq 'excused') {
		    $newscore = 'excused'; }
		if ($newscore eq 'ungraded') {
		    $newscore = 'ungraded_attempted'; }
	    } else {
		#$result.="$stuname:$part:$type:unchanged  $oldscore to $newscore:<br />\n";
	    }
	    if ($update) { $newrecord{"resource.$part.$type"}=$newscore; }
	} else {
	    if ($oldscore ne $newscore) {
		$newrecord{"resource.$part.$type"}=$newscore;
		$result .= "Updating $student"."'s status for $part.$type to ".
		           "$newscore<br />\n";
	    } else {
		#$result.="$stuname:$part:$type:unchanged  $oldscore to $newscore:<br />\n";
	    }
	}
    }
    if ( scalar(keys(%newrecord)) > 0 ) {
	$newrecord{"resource.regrader"} = $ENV{'user.name'}.':'.
	                                  $ENV{'user.domain'};
	&Apache::lonnet::cstore(\%newrecord,$symb,$courseid,$domain,$stuname);
	
	$result .= 'Stored away '.scalar(keys(%newrecord)).
  	           " elements.<br />\n";
    }
    return $result;
}


# ========================================================== Attempt submission
sub submission {
    my ($request) = @_;
    my $url = $ENV{'form.url'};
    $url =~ s-^http://($ENV{'SERVER_NAME'}|$ENV{'HTTP_HOST'})--;
    if ($ENV{'form.student'} eq '') { 
	&moreinfo($request,"Need student login id"); return ''; }
#  if ($ENV{'form.student'} eq '') { &listStudents($request); return ''; }
    my ($uname,$udom) = &finduser($ENV{'form.student'});
    if ($uname eq '') {
	&moreinfo($request,"Unable to find student"); return ''; }
    my $symb=&Apache::lonnet::symbread($url);
    if ($symb eq '') {
	$request->print("Unable to handle ambiguous references:$url:.");
	return ''; }
    my $answer = &Apache::loncommon::get_previous_attempt($symb,$uname,$udom,
		 $ENV{'request.course.id'});
    my $result = "<h2> Submission Record </h2>  $uname:$udom for $url <br />".
	         $answer;
    return $result;
}

# ================================================================= View grades
sub viewgrades {
    my ($request) = @_;
    my $result = '';
    
    #get resource reference
    my $url = $ENV{'form.url'};
    $url =~ s-^http://($ENV{'SERVER_NAME'}|$ENV{'HTTP_HOST'})--;
    my $symb=$ENV{'form.symb'};
    if (!$symb) { $symb = &Apache::lonnet::symbread($url); }
    if ($symb eq '') { 
	$request->print("Unable to handle ambiguous references:$url:.");
	return '';
    }
    
    #get classlist
    my ($cdom,$cnum) = split(/_/,$ENV{'request.course.id'});
    my $chome = $ENV{"course.$ENV{'request.course.id'}.home"};
    #print "Found $cdom:$cnum:$chome<br />";
    my (%classlist) = &getclasslist($cdom,$cnum,$chome,'0');
    my $headerclr = '"#ccffff"';
    my $cellclr = '"#ffffcc"';

    #get list of parts for this problem
    my (@parts) = &getpartlist($url);

    $request->print("<h2><font color=\"#339966\">Manual Grading</font></h2>");
    
    #start the form
    $result = '<form action="/adm/grades" method="post">'."\n".
	      '<input type="hidden" name="symb" value="'.$symb.'"/>'."\n".
	      '<input type="hidden" name="url" value="'.$url.'"/>'."\n".
	      '<input type="hidden" name="command" value="editgrades" />'."\n".
	      '<input type="submit" name="submit" value="Submit Changes" />'.
	      "\n".'<table border=0><tr><td bgcolor="#999999">'."\n".
	      '<table border=0>'."\n".
	      '<tr><td bgcolor='.$headerclr.'>UserId</td><td bgcolor='.
              $headerclr.'>Domain</td>'."\n";
    foreach my $part (@parts) {
	my $display = &Apache::lonnet::metadata($url,$part.'.display');
	if  (!$display) { 
	    $display = &Apache::lonnet::metadata($url,$part.'.name'); }
	$result .= '<td bgcolor='.$headerclr.'>'.$display.'</td>'."\n";
    }
    $result .= "</tr>";

    #get info for each student
    foreach my $student ( sort(@{ $classlist{'allids'} }) ) {
	$result .= &viewstudentgrade($url,$symb,$ENV{'request.course.id'},
				     $student,@parts);
    }
    $result .= '</table></td></tr></table><input type="submit" name="submit"'.
	       'value="Submit Changes" /></form>';
    return $result;
}

# ================================================================= Edit grades
sub editgrades {
    my ($request) = @_;
    my $result='';

    my $symb = $ENV{'form.symb'};
    if ($symb eq '') {
	$request->print("Unable to handle ambiguous references:$symb:".
			$ENV{'form.url'});
	return '';
    }
    my $url = $ENV{'form.url'};
    #get classlist
    my ($cdom,$cnum) = split(/_/,$ENV{'request.course.id'});
    my $chome = $ENV{"course.$ENV{'request.course.id'}.home"};
    #print "Found $cdom:$cnum:$chome<br />";
    my (%classlist) = &getclasslist($cdom,$cnum,$chome,'0');
    
    #get list of parts for this problem
    my (@parts) = &getpartlist($url);

    $result .= '<form action="/adm/grades" method="post">'."\n".
               '<input type="hidden" name="symb" value="'.$symb.'" />'."\n".
               '<input type="hidden" name="url" value="'.$url.'" />'."\n".
	       '<input type="hidden" name="command" value="viewgrades" />'.
               "\n".'<input type="submit" name="submit" value="See Grades" />'.
               '<br />'."\n";

    foreach my $student ( sort(@{ $classlist{'allids'} }) ) {
        $result .= &setstudentgrade($url,$symb,$ENV{'request.course.id'},
				    $student,@parts);
    }

    $result .= '<input type="submit" name="submit" value="See Grades" />'.
	       '</table></form>';
    return $result;
}

# ================================================================= Send header
sub send_header {
    my ($request) = @_;
    $request->print(&Apache::lontexconvert::header());
#  $request->print("
#<script>
#remotewindow=open('','homeworkremote');
#remotewindow.close();
#</script>"); 
    $request->print('<body bgcolor="#FFFFFF">');
}

# ================================================================= Send footer
sub send_footer {
  my ($request) = @_;
  $request->print('</body>');
  $request->print(&Apache::lontexconvert::footer());
}

# ===================================================================== Handler
sub handler {
    my $request = $_[0];
    if ( $ENV{'user.name'} eq 'albertel' ) {$Apache::lonxml::debug=1;}
    else {$Apache::lonxml::debug=0;}
    if ($ENV{'browser.mathml'}) {
	$request->content_type('text/xml');
    } else {
	$request->content_type('text/html');
    }
    $request->send_http_header;
    return OK if $request->header_only;
    my $url = $ENV{'form.url'};
    my $symb = $ENV{'form.symb'};
    my $command = $ENV{'form.command'};
    
    &send_header($request);
    if ($url eq '' && $symb eq '') {
	$request->print("Non-Contextual Access Unsupported:$command:$url:");
    } else {
	$Apache::grades::viewgrades=&Apache::lonnet::allowed('vgr',
				    $ENV{'request.course.id'});
	if ($command eq 'submission') {
	    $request->print(&listStudents($request))
		if ($ENV{'form.student'} eq '');
	    $request->print(&submission($request))
		if ($ENV{'form.student'} ne '');
	} elsif ($command eq 'viewgrades') {
	    $request->print(&viewgrades($request));
	} elsif ($command eq 'editgrades') {
	    $request->print(&editgrades($request));
	} else {
	    $request->print("Unknown action:$command:");
	}
    }
    &send_footer($request);
    return OK;
}

1;

__END__