torrent-dir.rb

#!/usr/bin/env ruby

require 'fileutils'
require 'torrent-ruby' # gem install torrent-ruby

buff = []
while true do
  begin
    buff << STDIN.read_nonblock(64000)
  rescue
    break
  end
end

if buff.empty? then
  STDERR.puts "no files given"
  exit 1
end

input = buff.join('')
files = input.split(/\n/)

files.each do |f|

  f = File.expand_path(f)
  t = TorrentFile.open(f)
  contents = t.to_h

  # cleanup filename
  # replace special chars with _
  # set name in torrent itself (so download dir is updated)
  ff = File.basename(f).gsub(/\.torrent$/, '').gsub(/[ .!&'"]/, '_')
  contents["info"]["name"] = ff

  t.create(contents)
  t.save(f) # save back to input file

  # rename to new name
  ff = File.join(File.dirname(f), ff + ".torrent")
  if f != ff then
    STDERR.puts "renamed #{ff}"
    FileUtils.mv(f, ff)
  end
end