#!/usr/bin/env perl

# xseed script for TheFriscoFainter
# @author leafy
# <3

use Bencode qw/ bencode bdecode /;
use Getopt::Long qw/ GetOptions /;
use Data::Dumper;
use File::Temp qw/ tempfile /;
use Digest::MD5 qw/ md5_base64 /;

my $usage = '
Usage: xseed.pl [options] -- filename [filename] ...

Options:
  -h, --help            show this help message and exit
  -e, --edit-in-place   overwrite files without prompting
  -o OUTFILE, --output=OUTFILE
                        specify output filename. (can not be used if multiple
                        files are given)
  -d PATH, --directory=PATH
                        specify a directory to save output to
  -p, --private         make torrent private

Written by leafy for TheFriscoFainter@baconbits
';

my %options = {
    "help" => "",
    "edit_in_place" => "",
    "output_file" => "",
    "output_dir" => "",
    "private" => ""
};
GetOptions(
    "help" => \$options{"help"},
    "h" => \$options{"help"},
    "e" => \$options{"edit_in_place"},
    "edit-in-place" => \$options{"edit_in_place"},
    "o=s" => \$options{"output_file"},
    "output=s" => \$options{"output_file"},
    "d=s" => \$options{"output_dir"},
    "directory=s" => \$options{"output_dir"},
    "p" => \$options{"private"},
    "private" => \$options{"private"}
);

if(1 == $options{"help"}) {
    print $usage;
    exit;
}

foreach my $filename (@ARGV) {
    open(my $h, "<", $filename); # File handle
    binmode($h);

    my $file = "";
    while(defined($_ = <$h>)) {
        $file .= $_;
    }

    my $torrent = bdecode $file;
    if(not defined($torrent->{"info"}->{"files"})) {
        # Single file mode - put into multiple file mode
        my %file;
        $file{"name"} = $torrent->{"info"}->{"name"};
        $file{"length"} = $torrent->{"info"}->{"length"};
        $file{"path"} = [$file{"name"}];

        if(defined($torrent->{"info"}->{"md5sum"})) {
            $file{"md5sum"} = $torrent->{"info"}->{"md5sum"};
        }

        $torrent->{"info"}->{"name"} = $file{"name"};
        delete $torrent->{"info"}->{"length"};
        delete $torrent->{"info"}->{"md5sum"};

        $torrent->{"info"}->{"files"} = [\%file];
    }

    # Generate a random filename

    my %randfile;
    $randfile{"name"} = md5_base64(time());
    $randfile{"length"} = 0;
    $randfile{"path"} = [$randfile{"name"}];


    push(@{$torrent->{"info"}->{"files"}}, \%randfile);

    if(1 == $options{"private"}) {
        $torrent->{"info"}->{"private"} = "1";
    }

    # Finished editing, encode it!

    $file = bencode $torrent;


    if(1 == $options{"edit_in_place"}) {
        open $h, "+>", $filename;
        binmode($h);
        print $h $file;
    }
    else {
        if(length(@ARGV) == 1) {
            # Single file
            if(not defined($options{"output_file"}) and not defined($options{"output_dir"})) {
                print STDERR "You didn't specify an output file or directory.";
                exit;
            }
            else {
                if(defined($options{"output_file"})) {
                    open $h, "+>", $options{"output_file"};
                }
                else {
                    open $h, "+>", ($options{"output_dir"} . "/" . $filename);
                }
            }
            binmode($h);
            print $h $file;
        }
    }
    close $h;
}