package Games::QuizTaker;
use strict;
use vars qw($AUTOLOAD $VERSION);
use Fcntl qw/:flock/;
use Text::Wrap;
use Carp;

$VERSION=1.24;

sub AUTOLOAD{
  my ($self)=@_;
  $AUTOLOAD=~/.*::[sg]et(_\w+)/ or croak "No such method: $AUTOLOAD";
  exists $self->{$1} or croak "No such attribute: $1";
  return $self->{$1};
}

sub DESTROY{
  my $self=shift;
  undef $self;
}

sub new{
  my($class,%arg)=@_;
    bless{ _Delimiter        => $arg{Delimiter}|| "|",
       _Answer_Delimiter => $arg{Answer_Delimiter}|| " ", 
           _Score            => $arg{Score}|| undef,
           _FileLength       => "0",
           _FileName         => $arg{FileName}||croak"No FileName give
+n",
       _Max_Questions    => "0",
         },$class;
}
  
sub load{
  my ($self,$Data)=@_;
  my $Question_File=$self->get_FileName;
  my $Separator=$self->get_Delimiter;
  my $Answer_Sep=$self->get_Answer_Delimiter;
  my ($question_number,$count);

  if($Answer_Sep eq $Separator){
    croak"The Delimiter and Answer_Delimiter are the same";
  }

  open(FH,"$Question_File")||croak"Can't open $Question_File: $!";
  flock(FH,LOCK_SH);
  while(<FH>){
    my @sorter;
    if(/^$/ or /^#/){}else{
      $count++;
      my $sep=qq"\\$Separator"; 
      @sorter=split /$sep/;
      $question_number=shift @sorter;
      my $ref=\@sorter;
      $$Data{$question_number}=$ref;    
    }
  }
  flock(FH,LOCK_UN);
  close FH;
  $self->set_FileLength($count);
  return $Data;   
}

sub generate{
  my ($self,$Data,$Max_Questions)=@_;
  my $Total_Questions=$self->get_FileLength;
  my $FileName=$self->get_FileName;
  
  $Max_Questions = $Total_Questions unless defined $Max_Questions;

  croak"Number of questions in $FileName exceeded"
    if $Max_Questions > $Total_Questions;

  croak"Must have at least one question in test"
    if $Max_Questions < 1;

  $self->set_Max_Questions($Max_Questions);

  my %Randoms=();
  my @Randoms=();
  my %Test_Questions=();
  my %Test_Answers=(); 
  
  for(1..$Max_Questions){
    my $question_number=int(rand($Total_Questions)+1);
    redo if exists $Randoms{$question_number};
    $Randoms{$question_number}=1;
  }

  @Randoms=keys %Randoms;
  $self->shuffle(\@Randoms);

  for(my $D=0;$D<$Max_Questions;$D++){
    $Test_Answers{$Randoms[$D]}=pop @{$$Data{$Randoms[$D]}};
    $Test_Questions{$Randoms[$D]} = $$Data{$Randoms[$D]};
  }
  
   return \%Test_Questions,\%Test_Answers,\@Randoms; 
}

sub test{
  my ($self,$Questions,$Answers,$Randoms)=@_;
  my $Answer_Sep=$self->get_Answer_Delimiter;
  my $Max=$self->get_Max_Questions;
  my ($answer,$key,$line,$question_answer);
  my $question_number=1;
  my $number_correct=0;
  my $asep=qq"\\$Answer_Sep";

  system(($^O eq "MSWin32"?'cls':'clear'));
  print"\n";

  while($question_number<=$Max){
    $key=shift @$Randoms;
  
    print"Question Number $question_number\n";

    foreach $line(@{$$Questions{$key}}){
      print wrap("","","$line\n");
    }

    print"Your Answer: ";
    $answer=<STDIN>;
    chomp($answer);
    $answer=uc $answer;
    $question_answer=$$Answers{$key};
    chomp($question_answer);
    $question_answer=uc $question_answer;

    my $ln=length($question_answer);

    if($ln>1){
      if($question_answer!~/$Answer_Sep/){
        warn"Answer_Delimiter doesn't match internally";
      }
      if($Answer_Sep eq " "){ }else{
        $question_answer=~s/$asep/ /;
      }
    }

    if($answer eq $question_answer){
      print"That is correct!!\n\n";
      $question_number++;
      $number_correct++;
    }else{
      print"That is incorrect!!\n";
      print"The correct answer is $question_answer.\n\n";
      $question_number++;
    }
  }
  my $Final=$self->get_Score;
  if(defined $Final){
    $self->Final($number_correct,$Max);
    return;
  }else{
    return;
  }
}

sub shuffle{
  ## Fisher-Yates shuffle ##
  my ($self,$array)=@_;
  my $x;
  for($x=@$array;--$x;){
    my $y=int rand ($x+1);
    next if $x == $y;
    @$array[$x,$y]=@$array[$y,$x];
  }
}

sub Final{
  my ($self,$Correct,$Max)=@_;
  
  if($Correct >= 1){
    my $Percentage=($Correct/$Max)*100;
    print"You answered $Correct out of $Max correctly.\n";
    printf"For a final score of %02d%%\n",$Percentage;
    return;
  }else{
    print"You answered 0 out of $Max correctly.\n";
    print"For a final score of 0%\n";
    return;
  }
}

sub set_FileLength{
  my $self=shift;
  my $count=shift;
  $$self{_FileLength}=$count;
}

sub set_Max_Questions{
  my $self=shift;
  my $Questions=shift;
  $$self{_Max_Questions}=$Questions;
}

sub get_FileLength{
  my $self=shift;
  return $$self{_FileLength};
}

sub get_Max_Questions{
  my $self=shift;
  return $$self{_Max_Questions};
}

sub get_FileName{
  my $self=shift;
  return $$self{_FileName};
}

sub get_Delimiter{
  my $self=shift;
  return $$self{_Delimiter};
}

sub get_Answer_Delimiter{
  my $self=shift;
  return $$self{_Answer_Delimiter};
}

sub get_Score{
  my $self=shift;
  return $$self{_Score};
}

#####################
## Debug Functions ##
#####################
sub Print_Object{
  my ($self,$structure)=@_;
  require Data::Dumper;

  if(defined $structure){
    print Data::Dumper->Dumper($structure);
  }else{
    print Data::Dumper->Dumper($self); 
  }
}

sub get_VERSION{
  my $self=shift;
  return $VERSION;
}
 
1;
__END__

=pod

=head1 NAME

Games::QuizTaker - Create and take your own quizzes and tests

=head1 SYNOPSIS

     use Games::QuizTaker;
     my $Q=Games::QuizTaker->new(FileName=>"sampleqa",Score=>1);
     my %Data=();
     my $rData=$Q->load(\%Data);
     my ($rQuestions,$rAnswers,$rRandoms)=$Q->generate(\%Data);
     $Q->test($rQuestions,$rAnswers,$rRandoms);

=head1 DESCRIPTION

=over 5

=item new

C<< new("FileName"=>"FILENAME","Delimiter"=>"Delimiter",Answer_Delimit
+er=>"Delimiter",Score=>"1"); >>

This creates the Games::QuizTaker object and initializes it with two
parameters. The FileName parameter is required, and the Delimiter is
optional. The Delimiter is what is used to separate the question and
answers in the question file. If the Delimiter parameter isn't passed,
it will default to the pipe ("|") character. The Answer_Delimiter is
used for questions that have more than one correct answer. If the
Answer_Delimiter parameter isn't passed, it will default to a space.
When answering the questions within the test that have more than one
answer, put a space between each answer. There is also a parameter cal
+led
Score that also can be passed to the object. If set, this parameter wi
+ll
print out a final score, giving the number of questions answered corre
+ctly,
and the overall percentage. By default, this is turned off. 

=item load

C<< $refHash=$QT->load(\%Data); >>

This function will load the hash with all of the questions and answers
from the file that you specify when you create the object. It also set
+s
another parameter within the $QT object called FileLength, which is th
+e
total number of questions within the file. It will also check to see i
+f
the _Answer_Delimiter parameter is the same as the _Delimiter paramete
+r.
If they are the same, then the program will croak.

=item generate

C<< ($refHash1,$refHash2,$refArray1)=$QT->generate(\%Data,$Max); >> 

This function will generate the 2 hashes and 1 array needed by the tes
+t
function. The first reference ($refHash1) are the questions that will 
+be
asked by the test function. The second reference ($refHash2) are the a
+nswers
to those questions. And $refArray1 is a sequence of random numbers tha
+t is
generated from the total number of questions ($Max) that you wish to a
+nswer.
The $refArray1 is also randomized further after its generation by the
internal _shuffle function which is a Fisher-Yates shuffle. If the max
+imum
number of questions you wish to answer on the quiz ($Max) is not passe
+d to
the function, it will default to the maximum number of questions in th
+e file
(determined by the FileLength parameter within the object). It will al
+so set
the Max_Questions parameter within the object, which will be later use
+d by
the test function to keep track of the number of questions printed out
+.

=item test

C<< $QT->test($refHash1,$refHash2,$refArray1); >>

This function will print out each question in the Questions hash, and 
+wait
for a response. It will then match that response against the Answers h
+ash.
If there is a match, it will keep track of the number of correct answe
+rs, and 
move on to the next question, other wise it will give the correct answ
+er, and
go to the next question. After the last question, it will pass the num
+ber
correct and the max number of questions on the test to the _Final func
+tion,
which prints out your final score.

=back

=head1 EXPORT

None by default

=head1 DEBUGGING

There is a single function available for debugging. When called, it wi
+ll
print out the contents of the object and its parameters.
 
=head1 ACKNOWLEDGEMENTS

Special thanks to everyone at http://perlmonks.org for their suggestio
+ns
and contributions to this module, and to Damian Conway for his excelle
+nt
book on Object Oriented Perl

Also, I would like to thank Chris Ahrends for his suggestions to impro
+ve this module, and to Mike Castle for pointing out a typo in my POD.

=head1 AUTHOR

Thomas Stanley

Thomas_J_Stanley@msn.com

I can also be found at http://perlmonks.org as TStanley. You can direc
+t
any questions relating to this module there.

=head1 COPYRIGHT

Copyright (C)2001-2003 Thomas Stanley. All rights reserved. This progr
+am is free
software; you can redistribute it and/or modify it under the same term
+s as
Perl itself.
 
=head1 SEE ALSO

I<perl(1)>

=cut