# The LON-CAPA Grading handler
# 2/9,2/13 Guy Albertelli

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);

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 '';
}


#FIXME - needs to be much smarter
sub finduser {
  my ($name) = @_;

  if ( $Apache::grades::viewgrades eq 'F' ) {
    return ($name,$ENV{'user.domain'});
  } else {
    return ($ENV{'user.name'},$ENV{'user.domain'});
  }
}

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;
    }
    push( @{ $classlist{'allids'} }, $name); 
  }
  return (%classlist);
}

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;
}

sub viewstudentgrade {
  my ($url,$symb,$courseid,$student,@parts) = @_;
  my $result ='';

  my ($stuname,$domain) = split(/:/,$student);

  my %record=&Apache::lonnet::restore($symb,$courseid,$domain,$stuname,
				      &Apache::lonnet::homeserver($stuname,$domain));

  $result.="<tr><td>$stuname</td><td>$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"};
      $result.="<td><input type=\"text\" name=\"GRADE.$student.$part.$type\" value=\"$score\" size=\"4\" /></td>\n";
    } elsif ($type eq 'tries') {
      my $score=$record{"resource.$part.$type"};
      $result.="<td><input type=\"text\" name=\"GRADE.$student.$part.$type\" value=\"$score\" size=\"4\" /></td>\n"
    } elsif ($type eq 'solved') {
      my $score=$record{"resource.$part.$type"};
      $result.="<td><select name=\"GRADE.$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 $result;
}
#FIXME need to look at the meatdata <stores> spec on what type of data to accept and provide an
#interface based on that, also do that to above function.
sub setstudentgrade {
  my ($url,$symb,$courseid,$student,@parts) = @_;

  my $result ='';

  my ($stuname,$domain) = split(/:/,$student);

  my %record=&Apache::lonnet::restore($symb,$courseid,$domain,$stuname,
				      &Apache::lonnet::homeserver($stuname,$domain));
  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,$stuname,
			    &Apache::lonnet::homeserver($stuname,$domain));
    $result.="Stored away ".scalar(keys(%newrecord))." elements.<br />\n";
  }
  return $result;
}

sub submission {
  my ($request) = @_;
  my $url=$ENV{'form.url'};
  $url=~s-^http://($ENV{'SERVER_NAME'}|$ENV{'HTTP_HOST'})--;
  if ($ENV{'form.student'} eq '') { &moreinfo($request,"Need student login id"); return ''; }
  my ($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 $home=&Apache::lonnet::homeserver($uname,$udom);
  my $answer=&Apache::loncommon::get_previous_attempt($symb,$uname,$udom,$home,
						      $ENV{'request.course.id'});
  my $result="<h2> Submission Record </h2>  $uname:$udom for $url".$answer;
  return $result;
}

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');


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

  #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>'."\n".
	      '<tr><td>UserId</td><td>Domain</td>'."\n";
  foreach my $part (@parts) {
     my $display=&Apache::lonnet::metadata($url,$part.'.display');
     if  (!$display) { $display = &Apache::lonnet::metadata($url,$part.'.name'); }
     $result.="<td>$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><input type="submit" name="submit" value="Submit Changes" /></form>';

  return $result;
}

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;
}

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

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

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') {
      $request->print(&submission($request));
    } 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__;