#!/usr/bin/perl -w

use strict;
use File::Find;
use File::Basename;
use File::stat;
use File::Slurp qw(read_dir);

my @directories = qw( /all_files_a /all_files_b);
my @files;

my $min_size = 1024; # bytes => 1K
my $max_size = 10485760; # bytes =>10MB

for my $d (@directories) {    
                      
    push @files, grep { -f && -s _ >= $min_size && -s _ <= $max_size && /\.pdf/} read_dir( $d, prefix => 1 );
}

my $limit = 5_000_000;

print "Getting file sizes...\n";
$_ = -s $_ foreach (@files);

#Create zip with $limit of files per zip
print "Creating zips...\n";
my $zip_number = 1;
my $total_size = 0;
my @other_group;

while(@files or @other_group) {
	
	#Find biggest file that will fit
	my $next_index = 0;
	   $next_index++ while( ($next_index <= $#files) && ($total_size + $files[$next_index] > $limit) );
        
        #If there was a file that will fit, add it to @other_group        
        if($next_index <= $#files) {
	  
          push @other_group, splice(@files, $next_index, 0);
          $total_size += $other_group[0];

	}
	#Otherwise, zip this group, and start a new group
	else {
		
		# print this for testing, these files will be zipped in the $zip_number.zip file
		foreach my $testfiles (@other_group) { 
		  print "\n$testfiles - $zip_number.zip\n";
	         }		
		
		#Clear this group info, and increment zip number
		@other_group = ();
		$total_size = 0;
		$zip_number++;

	}

}