#!/opt/bin/perl

# recompress all .zip-files in current dir to Books/*/*/*.zip dir tree: 1 file per zip archive entity
#
# looks like old Archive::Zip have tiny mem leak - it leaks ~50+ Mb per 15k files


use strict;
use warnings "all";

use File::Path;
use Archive::Zip qw(:ERROR_CODES :CONSTANTS);

sub mkzip(@);
sub pathgen();

my $FILES_PER_DIR = 1000;
my $DIRS_PER_DIR = 1000;
my $BASEDIR = $ARGV[0];
my @OUTPATH = ($BASEDIR, undef, undef);
my $FILECOUNTER = undef;
my $TMPDIR = 'tmp';

opendir(DIR, ".");
my @ziplist = grep { /\.zip$/ } readdir(DIR);
closedir(DIR);
@ziplist = reverse(sort(@ziplist));

while (my $zipfile = pop(@ziplist)) {
	syswrite STDOUT, "Processing $zipfile.\n";
	my $zip = Archive::Zip->new;
	Archive::Zip::setChunkSize(1048576);

	unless ( $zip->read( $zipfile ) == AZ_OK ) {
		syswrite STDERR, sprintf("Unable to read %s, skipping\n", $zipfile);
		undef $zip;
		undef $zipfile;
		next;
	}

    undef $zipfile;
	my @members = reverse($zip->members());
	my $mbrnum = 1;
	my $mbrlen = int(@members);

	while (my $mbr = pop(@members)) {
		syswrite STDOUT, sprintf("Entity %s/%s.\r", $mbrnum, $mbrlen);
		my $content = $zip->contents($mbr);

		unless(defined($content)){
			printf("Unable to extract %s, skipping.\n", $mbr->{'fileName'});
			next;
		}

		mkzip($content, $mbr);
		undef $content;
		undef $mbr;
		$mbrnum++;
	}

	@members = -1; undef @members;
	undef $zip;
	undef $mbrnum;
}

@ziplist = -1; undef @ziplist;
syswrite STDOUT, "\nDone.\n";
exit 0;

sub mkzip(@){
	my $content = shift;
	my $mbr = shift;

	unless(defined($FILECOUNTER)) {
		$FILECOUNTER = 0;
		pathgen();
	} else {
		if ($FILECOUNTER >= $FILES_PER_DIR) {
			pathgen();
			$FILECOUNTER = 0;
		} else {
			$FILECOUNTER++;
		}
	}

	my $destdir = join('/', @OUTPATH);

	unless (-d $destdir) {
# actually we need to check if path really created
		if ( scalar(mkpath($destdir)) < 1 ) {
			printf("Unable to create %s, quitting.", $destdir);
			exit 1;
		}
	}

	my $newzip = Archive::Zip->new();
	my $zippy = $newzip->addString($content);

	if (defined($zippy)) {
		$zippy->fileName($mbr->{'fileName'});
		$zippy->setLastModFileDateTimeFromUnix( $mbr->{'lastModFileDateTime'} );
		$zippy->desiredCompressionMethod(COMPRESSION_DEFLATED);
		$zippy->desiredCompressionLevel(COMPRESSION_LEVEL_BEST_COMPRESSION);

		unless ( $newzip->writeToFileNamed("$destdir/$mbr->{'fileName'}.zip") == AZ_OK ) {
			printf ("Warning: unable to write to %s/%s.zip\n", $destdir, $mbr->{'fileName'});
		}
	} else {
		printf ("Warning: unable to add %s to zip-file\n", $mbr->{'fileName'});
	}

	undef $zippy;
	undef $newzip;
	undef $content;
	undef $mbr;
	undef $destdir;
}

sub pathgen() {
	unless (defined($OUTPATH[1])) {
		$OUTPATH[1] = 0;
	}

	unless (defined($OUTPATH[2])) {
		$OUTPATH[2] = 0;
	} else {
		$OUTPATH[2]++;

		if ($OUTPATH[2] > $DIRS_PER_DIR) {
			$OUTPATH[1]++;
			$OUTPATH[2] = 0;
		}
	}
}