use strict;
use warnings;

my $f=shift || die "File that your want to split\n";
my $chunk_size=shift || die "Chunk size\n";
my $dir=shift || die "Directory where the chunks are stored\n";
my $fsize=-s $f;
my $size=0;
my $buffer;
my $BUFFER_SIZE=4096;
my $nr_of_chunks=0;
my $nr=0;

if($chunk_size=~/(\d+)([mMgG])/) {
	my $numb=$1;
	my $tp=$2;
	SW: {
		($tp eq "g" || $tp eq "G") && do {
			$numb*=1024*1024*1024;
			$size=$numb;
			last SW;
		};
		($tp eq "m" || $tp eq "M") && do {
			$numb*=1024*1024;
			$size=$numb;
			last SW;
		};
	}
}
else {
	$size=$chunk_size;
}

open(F,$f) || die "OPEN : $!\n";
binmode(F);
if(! -e $dir) {
	mkdir($dir) || die "DIR : $!\n";
}
chdir($dir) || die "CHDIR : $!\n";

FILE:{
if(($fsize - $size)<=0) { 
	my $count=0;
	print "Creating file $nr\n";
	open(C,">$nr") || die "CREATE : $!\n";
	binmode(C);
        while($count != $fsize) {
		$count+=read(F,$buffer,$BUFFER_SIZE);
		print C $buffer;
	}
	close C;
	last FILE;
}
else {
	my $count=0;
	print "Creating file $nr\n";
	open(C,">$nr") || die "CREATE : $!\n";
	binmode(C);
        while($count != $size) {
		$count+=read(F,$buffer,$BUFFER_SIZE);
		print C $buffer;
	}
	close C;
	$fsize-=$size;
	$nr++;
	redo FILE;
}
}

print "Over & Out\n";