#!/usr/bin/env ruby

require "fileutils"

MUSIC_DIR = "/pegasus/pub/music/artists"
ARTISTS = <<EOS.split("\n").map(&:strip).sort
All That Remains
Avenged Sevenfold
Falling in Reverse
Fear Factory
Five Finger Death Punch
Godsmack
In Flames
Korn
Lamb of God
Linkin Park
Machine Head
Mudvayne
POD
Slipknot
Staind
Static-X
System of a Down
The Goo Goo Dolls
The Offspring
Tool
Trivium
EOS
MOUNT_DIR = "/tmp/mk-usb-car-music"

def run(*cmd)
  puts cmd.map {|p| "'#{p}'"}.join(" ")
  system(*cmd) or raise
end

def main(args)
  if args.find {|a| %w[-h --help].include?(a)}
    puts <<EOS
Usage: #{$0}
  -h, --help  Show this help and exit
  -s          Show folder sizes and exit
  -d DEV      Set USB device
EOS
    return 0
  end
  if args.find {|a| a == "-s"}
    run("du", "-shc", *ARTISTS.map {|a| "#{MUSIC_DIR}/#{a}"})
    return 0
  end
  device = ""
  args.each_with_index do |arg, i|
    if arg =~ /^-d(.*)$/
      device = $1
      if device == "" and args.length > (i + 1)
        device = args[i + 1]
      end
    end
  end
  if device == ""
    $stderr.puts "Specify device."
    return 1
  end
  run(*%W[sudo mkfs.vfat -n JOSHMUSIC #{device}]) or raise
  FileUtils.rm_rf(MOUNT_DIR)
  FileUtils.mkdir(MOUNT_DIR)
  run(*%W[sudo mount #{device} #{MOUNT_DIR} -o uid=#{`whoami`.chomp}]) or raise
  begin
    ARTISTS.each do |artist|
      src = "#{MUSIC_DIR}/#{artist}"
      dest = "#{MOUNT_DIR}/#{artist}"
      src_folders = Dir["#{src}/*"].select do |path|
        File.directory?(path)
      end.sort
      FileUtils.mkdir(dest)
      src_folders.each do |src_folder|
        puts "Copying #{src_folder}..."
        dest_folder = "#{dest}/#{File.basename(src_folder)}"
        FileUtils.mkdir(dest_folder)
        src_files = Dir["#{src_folder}/*"].select do |path|
          File.file?(path)
        end.sort
        src_files.each do |src_file|
          FileUtils.cp(src_file, dest_folder)
        end
      end
    end
  ensure
    run(*%W[sudo umount #{MOUNT_DIR}]) or raise
  end
  return 0
end

exit(main(ARGV))