use strict;
use warnings;
use Getopt::Long;
use List::Util qw(min);
use vars qw/$Fuzz $Words $Word_Size $Strings $String_Size $OverWrite/;
exit(main());

BEGIN {
  $Fuzz=2;
  $Words=1000;
  $Word_Size=25;
  $Strings=100;
  $String_Size=1000;
  $OverWrite=0;
}

sub opts_msg {
  warn @_,"\nLegal Opts (with defaults):\n\t--fuzz=$Fuzz --words=$Words --strings=$Strings\n".
          "\t--word_size=$Word_Size --string_size=$String_Size \n".
         "\t--over_write --verbose\n";
  1;
}

sub main {
  $|++;

  my $help;
  my $VERBOSE;


  GetOptions('fuzz=i'       => \$Fuzz,
             'words=i'      => \$Words,
             'strings=i'    => \$Strings,
             'word_size=i'  => \$Word_Size,
             'string_size=i'=> \$String_Size,
             'over_write!'  => \$OverWrite,
             'verbose!'     => \$VERBOSE,
             'help'         => \$help)
  or return opts_msg("Bad Option Provided.");

  return opts_msg() if $help;

  my @Chars=qw(A C G T);

  my $file=sprintf "FT-SC%04d-SL%07d-F%02d-WC%07d-WL%03d.fuzztest",
          #map { $_>=1000 ? int($_/1000)."k" : $_ }
           $Strings,$String_Size,$Fuzz,$Words,$Word_Size;

  if (!$OverWrite and -e $file) {
    warn "Test file '$file' exists already\n";
    warn "Use --over_write to force\n";
    print $file,"\n";
    return 1;
  }
  open my $fh,">",$file or die "Error writing to '$file':$!";

  warn "Writing '$file'\n" if $VERBOSE;
  # Header
  print $fh '$Fuzz,$Words,$Word_Size,$Strings,$String_Size,$chars',"\n";
  print $fh "$Fuzz,$Words,$Word_Size,$Strings,$String_Size,",@Chars,"\n";

  # Words
  my @words;
  my $count=$String_Size/$Word_Size/2;

  warn "With $Words words of $Word_Size random chars: (@Chars)\n"
    if $VERBOSE;
  for (1..$Words) {
    my $str=join "",map { $Chars[rand @Chars] } 1..$Word_Size;
    if (@words<$count) {
      push @words,$str;
    } else {
      $words[rand @words]=$str
        unless int rand $count/2;
    }
    print $fh $str,"\n";
  }
  print $fh "---\n";
  # Strings
  warn "And $Strings random strings of length $String_Size\n"
    if $VERBOSE;

  for (1..$Strings) {
    my $str="A" x $String_Size;
    substr($str,$_,1,$Chars[rand @Chars])
      for 0..$String_Size-1;
    for (1..$count) {
        my $p=int rand($String_Size-$Word_Size);
        my $w=$words[rand @words];
        substr($w,int(rand length $w),1)=$Chars[rand @Chars]
          for 1..rand $Fuzz+1;
        substr($str,$p,$Word_Size,$w);
    }
    print $fh $str,"\n"
  }
  close $fh
    or die "Failed to close '$file'\n";
  warn "Done.\n"
    if $VERBOSE;
  print $file,"\n";
  return 0;
}