#! /usr/bin/perl

use strict;
use threads;
use Image::Magick;

# Number of sumultaneous conversions
my $max_jobs = 5;

# Get existing images to convert
my @endgames_orig = glob("endgame-??-??-??-??.bmp");
my @screenshots_orig = glob("screenshot-??-??-??-??.bmp");

# Get existing conversions to check where we should leave off
my @endgames_done = glob("endgame*.png");
my @screenshots_done = glob("screenshot*.png");

# Counters for current position on where to start
my $end_pos = 1;
my $scrot_pos = 1;

my @threads;	# Worker threads
my @work;	# Job queue

foreach (@endgames_done) {
	$end_pos = $1 >= $end_pos ? ($1 + 1) : $end_pos if m/^endgame(\d+)\.png$/;
}

foreach (@screenshots_done) {
	$scrot_pos = $1 >= $scrot_pos ? ($1 + 1) : $scrot_pos if m/^screenshot(\d+)\.png$/;
}

foreach (@endgames_orig) {
	push(@work, [$_, "endgame".$end_pos++.".png"]);
}

foreach (@screenshots_orig) {
	push(@work, [$_, "screenshot".$scrot_pos++.".png"]);
}

while (1) {

	# Make new workers
	while (scalar @threads < $max_jobs) {
		if (my $job = pop(@work)) {
			push @threads, threads->create(sub {
				threads->self()->detach();
				my ($src, $dest) = @_;
				my $image = new Image::Magick;
				$image->Read($src);
				$image->Write($dest);
				unlink $src;
				print "Done with $src -> $dest\n";
			}, @$job[0], @$job[1]);
		}
		else {
			print "No more images to deal with\n";
			goto done;
		}
	}

	# Periodically reap dead shit to free up new slots
	for (my $i = 0; $i < scalar @threads; $i++) {
		delete @threads[$i] if $threads[$i] != undef && !$threads[$i]->is_running();
	}
}

done:
print "Done";