################################################################################
# WeBWorK mod_perl (c) 2000-2002 WeBWorK Project
# $Id$
################################################################################

package WeBWorK::ContentGenerator::Instructor::Stats;
use base qw(WeBWorK::ContentGenerator::Instructor);

=head1 NAME

WeBWorK::ContentGenerator::Instructor::Stats - Display statistics by user or
problem set.

=cut

use strict;
use warnings;
use CGI qw();
use WeBWorK::Utils qw(readDirectory list2hash max);
use WeBWorK::DB::Record::Set;


sub initialize {
	my $self     = shift; 
	# FIXME  are there args here?
	my $type       = shift || '';
	my @components = @_;
	my $r = $self->{r};
	my $db = $self->{db};
	my $ce = $self->{ce};
	my $authz = $self->{authz};
 	my $user = $r->param('user');
 	my $setName = $_[0];
 	$setName = 0 unless defined($setName);  #FIXME relay to index page for statistics
 	my $setRecord = $db->getGlobalSet($setName);
 	$self->{set}   = $setRecord;
 	$self->{type}  = $type;
 	if ($type eq 'student') {
 		$self->{studentName } = $components[0] || $user;
 		
 	} elsif ($type eq 'set') {
 		$self->{setName}     = $components[0]  || 0 ;
 	}
 	
 	
}

sub path {
	my $self       = shift;
	my $args       = $_[-1];
	my $ce         = $self->{ce};
	my $root       = $ce->{webworkURLs}->{root};
	my $courseName = $ce->{courseName};
	
	return $self->pathMacro($args,
		"Home"          => "$root",
		$courseName     => "$root/$courseName",
		'instructor'    => "$root/$courseName/instructor",
		'stats'         => "$root/$courseName/instructor/stats/",
		( $self->{type} eq 'set')     ? ("set/".$self->{setName}  => '')        : ''   ,
		( $self->{type} eq 'student') ? ("student/".$self->{studentName} => '') : ''   ,
	);
}

sub title { 
	my ($self, @components) = @_;
	my $type                = $self->{type};
	my $string              = "Statistics for ".$self->{ce}->{courseName}." ";
	if ($type eq 'student') {
		$string             .= "student ".$self->{studentName};
	} elsif ($type eq 'set' ) {
		$string             .= "set   ".$self->{setName};
	}
	return $string;
}
sub body {
	my $self       = shift;
	my $args       = pop(@_);
	my $type       = $self->{type};
	if ($type eq 'student') {
		$self->displayStudents($self->{studentName});
	} elsif( $type eq 'set') {
		my $setName = $self->{setName};
		$self->displaySets($self->{setName});
	} elsif ($type eq '') {
		$self->index;
	} else {
		warn "Don't recognize statistics display type: |$type|";

	}
	

	return '';

}
sub index {
	my $self          = shift;
	my $ce            = $self->{ce};
	my $r             = $self->{r};
	my $courseName    = $ce->{courseName};
	my $db            = $self->{db};
	my @studentList   = sort $db->listUsers;
	my @setList       = sort  $db->listGlobalSets;
	my $uri           = $r->uri;
	my @setLinks      = ();
	my @studentLinks  = (); 
	foreach my $set (@setList) {
		push @setLinks, CGI::a({-href=>"${uri}set/$set/?".$self->url_authen_args },"set $set" );	
	}
	
	foreach my $student (@studentList) {
		push @studentLinks, CGI::a({-href=>"${uri}student/$student/?".$self->url_authen_args},"  $student" ),;	
	}
	print join("",
		CGI::start_table({-border=>2, -cellpadding=>20}),
		CGI::Tr(
			CGI::td({-valign=>'top'}, 
				CGI::h3({-align=>'center'},'View statistics by set'),
				CGI::ul(  CGI::li( [@setLinks] ) ), 
			),
			CGI::td({-valign=>'top'}, 
				CGI::h3({-align=>'center'},'View statistics by student'),
				CGI::ul(CGI::li( [ @studentLinks ] ) ),
			),
		),
		CGI::end_table(),
	);
	
}
sub displaySets {
	my $self    = shift;
	#FIXME
	my $setName = shift;
	
	my $r          = $self->{r};
	my $db         = $self->{db};
	my $ce         = $self->{ce};
	my $authz      = $self->{authz};
	my $user       = $r->param('user');
	my $courseName = $ce->{courseName};
	my $setRecord  = $db->getGlobalSet($setName);
	my $root       = $ce->{webworkURLs}->{root};
	my $url        = $r->uri; 
	my $sort_method_name = $r->param('sort');  
	my @studentList   = $db->listUsers;

	my $sort_method = sub {
		my ($a,$b) = @_;
		return 0 unless defined($sort_method_name);
		return $b->{score} <=> $a->{score} if $sort_method_name eq 'score';
		return $b->{index} <=> $a->{index} if $sort_method_name eq 'index';
		return $a->{section} cmp $b->{section} if $sort_method_name eq 'section';
		if ($sort_method_name =~/p(\d+)/) {
			return $b->{problemData}->{$1} <=> $a->{problemData}->{$1};  # sort by number of attempts.
		}

	};
	#FIXME  need to be able to sort by index and score as well.
###############################################################
#  Print table
###############################################################
	my @problems = sort {$a <=> $b } $db->listUserProblems($user, $setName);

	# FIXME I'm assuming the problems are all the same

	my $num_of_problems  = @problems;
	# get user records
	my @userRecords  = $db->getUsers(@studentList);


 	my @augmentedUserRecords    = ();
	foreach my $studentRecord (@userRecords)   {
		my $student = $studentRecord->user_id;
		next if $studentRecord->last_name =~/^practice/i;  # don't show practice users
		next if $studentRecord->status !~/C/;              # don't show dropped students FIXME
	    my $status = 0;
	    my $attempted = 0;
	    my $longStatus = '';
	    my $string     = '';
	    my $twoString  = '';
	    my $totalRight = 0;
	    my $total      = 0;
		my $num_of_attempts = 0;
		my %h_problemData  = ();
		my $probNum         = 0;
		foreach my $prob (@problems) {
			my $problemRecord   = $db->getUserProblem($student, $setName, $prob);
			$probNum++;
			my $valid_status    = 0;
			unless (defined($problemRecord) ){
				# warn "Can't find record for problem $prob in set $setName for $student";
				# FIXME check the legitimate reasons why a student record might not be defined
				next;
			}
	    	$status             = $problemRecord->status || 0;
	        $attempted          = $problemRecord->attempted;
			if (!$attempted){
				$longStatus     = '.  ';
			}
			elsif   ($status >= 0 and $status <=1 ) {
				$valid_status   = 1;
				$longStatus     = int(100*$status+.5);
				if ($longStatus == 100) {
					$longStatus = 'C  ';
				}
				else {
					$longStatus = &threeSpaceFill($longStatus);
				}
			}
			else	{
				$longStatus 	= 'X  ';
			}

			my $incorrect     = $problemRecord->num_incorrect || 0; 
			# It's possible that $incorrect is an empty or blank string instead of 0  the || clause fixes this and prevents 
			# warning messages in the comparison below.
			$incorrect        = ($incorrect < 99) ? $incorrect: 99;  # take min
			$string          .=  $longStatus;
			$twoString       .= threeSpaceFill($incorrect);
			my $probValue     = $problemRecord->value;
			$probValue        = 1 unless defined($probValue);  # FIXME?? set defaults here?
			$total           += $probValue;
			$totalRight      += round_score($status*$probValue) if $valid_status;
			my $num_correct   = $problemRecord->num_incorrect || 0;
			my $num_incorrect = $problemRecord->num_correct   || 0;
			$num_of_attempts += $num_correct + $num_incorrect;
			$h_problemData{$probNum} = $incorrect;
		}
		# FIXME   we can do this more effficiently  get the list first
		
		
		my $act_as_student_url = "$root/$courseName/$setName?user=".$r->param("user").
			"&effectiveUser=".$studentRecord->user_id()."&key=".$r->param("key");
		my $email    = $studentRecord->email_address;
		# FIXME  this needs formatting
		
		my $avg_num_attempts = ($num_of_problems) ? $num_of_attempts/$num_of_problems : 0;
		my $successIndicator = ($avg_num_attempts) ? ($totalRight/$total)**2/$avg_num_attempts : 0 ;
		my $temp_hash         = {    user_id     => $studentRecord->user_id,
		                                  last_name      => $studentRecord->last_name,
		                                  first_name     => $studentRecord->first_name,
		                                  score          => $totalRight,
		                                  total          => $total,
		                                  index          => $successIndicator,
		                                  section        => $studentRecord->section,
		                                  recitation     => $studentRecord->recitation,
		                                  problemString  => "<pre>$string\n$twoString</pre>",
		                                  act_as_student => $act_as_student_url,
		                                  email_address  => $studentRecord->email_address,
		                                  problemData    => {%h_problemData},
		}; 
		push( @augmentedUserRecords, $temp_hash );
		                                
	}	
	
	@augmentedUserRecords = sort {           &$sort_method($a,$b)
												||
							lc($a->{last_name}) cmp lc($b->{last_name} ) } @augmentedUserRecords;
							
		# construct header
	my $problem_header = '';
	my $i=0;
	foreach (@problems) {
	    $i++;
		$problem_header .= CGI::a({"href"=>$url."?".$self->url_authen_args."&sort=p$i"},threeSpaceFill($i) );
	}
	print
	    defined($sort_method_name) ?"sort method is $sort_method_name":"",
		CGI::start_table({-border=>5}),
		CGI::Tr(CGI::th(  {-align=>'center'},
			[CGI::a({"href"=>$url."?".$self->url_authen_args."&sort=name"},'Name'),
			 CGI::a({"href"=>$url."?".$self->url_authen_args."&sort=score"},'Score'),
			 'Out'.CGI::br().'Of',
			 CGI::a({"href"=>$url."?".$self->url_authen_args."&sort=index"},'Ind'),
			 '<pre>Problems'.CGI::br().$problem_header.'</pre>',
			 CGI::a({"href"=>$url."?".$self->url_authen_args."&sort=section"},'Section'),
			 'Recitation',
			 'login_name',
			 ])

		);
								
	foreach my $rec (@augmentedUserRecords) {
		my $fullName = join("", $rec->{first_name}," ", $rec->{last_name});
		my $email    = $rec->{email_address}; 
		my $twoString  = $rec->{twoString};                             
		print CGI::Tr(
			CGI::td(CGI::a({-href=>$rec->{act_as_student}},$fullName), CGI::br(), CGI::a({-href=>"mailto:$email"},$email)),
			CGI::td( sprintf("%0.2f",$rec->{score}) ), # score
			CGI::td($rec->{total}), # out of 
			CGI::td(sprintf("%0.0f",100*($rec->{index}) )),   # indicator
			CGI::td($rec->{problemString}), # problems
			CGI::td($rec->{section}),
			CGI::td($rec->{recitation}),
			CGI::td($rec->{user_id}),			
			
		);
	}

	print CGI::end_table();
			
			

			
	return "";
}
sub displayStudents {
	my $self     = shift;
	my $studentName  = shift;
	my $r = $self->{r};
	my $db = $self->{db};
	my $ce = $self->{ce};
	my $courseName = $ce->{courseName};
	my $studentRecord = $db->getUser($studentName);
	my $root = $ce->{webworkURLs}->{root};
	
	my @setIDs    = sort $db->listUserSets($studentName);
	my $fullName = join("", $studentRecord->first_name," ", $studentRecord->last_name);
	my $act_as_student_url = "$root/$courseName/?user=".$r->param("user").
			"&effectiveUser=".$studentRecord->user_id()."&key=".$r->param("key");

	my $email    = $studentRecord->email_address;
	print CGI::h3($fullName ), 
	CGI::a({-href=>"mailto:$email"},$email),CGI::br(),
	"Section: ", $studentRecord->section, CGI::br(),
	"Recitation: ", $studentRecord->recitation,CGI::br(),
	CGI::a({-href=>$act_as_student_url},$studentRecord->user_id);	
	
	###############################################################
	#  Print table
	###############################################################

	# FIXME I'm assuming the problems are all the same
	# FIXME what does this mean?
	
	my @rows;
	my $max_problems;
	
	foreach my $setName (@setIDs)   {
	    my $status = 0;
	    my $attempted = 0;
	    my $longStatus = '';
	    my $string     = '';
	    my $twoString  = '';
	    my $totalRight = 0;
	    my $total      = 0;
		my $num_of_attempts = 0;
		my @problems = sort {$a <=> $b } $db->listUserProblems($studentName, $setName);
		my $num_of_problems  = @problems;
		$max_problems = $num_of_problems if $num_of_problems > $max_problems;
		# construct header
		foreach my $prob (@problems) {
			my $problemRecord      = $db->getUserProblem($studentName, $setName, $prob);
			
			my $valid_status    = 0;
			unless (defined($problemRecord) ){
				# warn "Can't find record for problem $prob in set $setName for $student";
				# FIXME check the legitimate reasons why a student record might not be defined
				next;
			}
	    	$status             = $problemRecord->status || 0;
	        $attempted          = $problemRecord->attempted;
			if (!$attempted){
				$longStatus     = '.  ';
			}
			elsif   ($status >= 0 and $status <=1 ) {
				$valid_status   = 1;
				$longStatus     = int(100*$status+.5);
				if ($longStatus == 100) {
					$longStatus = 'C  ';
				}
				else {
					$longStatus = &threeSpaceFill($longStatus);
				}
			}
			else	{
				$longStatus 	= 'X  ';
			}

			my $incorrect     = $problemRecord->num_incorrect;
			$incorrect        = ($incorrect < 99) ? $incorrect: 99;  # take min
			$string          .=  $longStatus;
			$twoString       .= threeSpaceFill($incorrect);
			my $probValue     = $problemRecord->value;
			$probValue        = 1 unless defined($probValue);  # FIXME?? set defaults here?
			$total           += $probValue;
			$totalRight      += round_score($status*$probValue) if $valid_status;
			my $num_correct   = $problemRecord->num_incorrect || 0;
			my $num_incorrect = $problemRecord->num_correct   || 0;
			$num_of_attempts += $num_correct + $num_incorrect;
		}
		# FIXME   we can do this more effficiently  get the list first
		

		# FIXME  this needs formatting
		
		my $avg_num_attempts = ($num_of_problems) ? $num_of_attempts/$num_of_problems : 0;
		my $successIndicator = ($avg_num_attempts) ? ($totalRight/$total)**2/$avg_num_attempts : 0 ;
	
		push @rows, CGI::Tr(
			CGI::td($setName),
			CGI::td(sprintf("%0.2f",$totalRight)), # score
			CGI::td($total), # out of 
			CGI::td(sprintf("%0.0f",100*$successIndicator)),   # indicator
			CGI::td("<pre>$string\n$twoString</pre>"), # problems
			#CGI::td($studentRecord->section),
			#CGI::td($studentRecord->recitation),
			#CGI::td($studentRecord->user_id),			
			
		);
	
	}
	
	my $problem_header = "";
	foreach (1 .. $max_problems) {
		$problem_header .= &threeSpaceFill($_);
	}
	
	my $table_header = join("\n",
		CGI::start_table({-border=>5}),
		CGI::Tr(
			CGI::th({ -align=>'center',},'Set'),
			CGI::th({ -align=>'center', },'Score'),
			CGI::th({ -align=>'center', },'Out'.CGI::br().'Of'),
			CGI::th({ -align=>'center', },'Ind'),
			CGI::th({ -align=>'center', },'Problems'.CGI::br().CGI::pre($problem_header)),
			#CGI::th({ -align=>'center', },'Section'),
			#CGI::th({ -align=>'center', },'Recitation'),
			#CGI::th({ -align=>'center', },'login_name'),
			#CGI::th({ -align=>'center', },'ID'),
		)
	);
	
	print $table_header;
	print @rows;
	print CGI::end_table();
			
	return "";
}

#################################
# Utility function NOT a method
#################################
sub threeSpaceFill {
    my $num = shift @_ || 0;
    
    if ($num < 10) {return "$num".'  ';}
    elsif ($num < 100) {return "$num".' ';}
    else {return "$num";}
}
sub round_score{
	return shift;
}
1;