id3dump.rb

#!/usr/bin/ruby

require 'rubygems'
require 'id3lib'

def usage()
  STDERR.puts "Usage: id3dump <mp3-file>"
  exit 1
end

if ARGV.length != 1 then
  usage
end
file = ARGV[0]
if !File.readable? ARGV[0] then
  STDERR.puts "Error: Cannot read the file you provided. [#{file}]"
  usage
end

tags = ID3Lib::Tag.new(file)

v1_tags = [:title, :artist, :album, :year, :composer, :genre, :track]
v1_max_len = v1_tags.map {|i| i.to_s.length}.max
puts "some common v1 tags {"
v1_tags.each { |tag|
  printf "  %-#{v1_max_len + 1}s \"%s\"\n", tag.to_s + ":", tags.send(tag)
}
puts "}"

puts "v2 tags {"
avoid = [:COMM, :APIC]
tags.reject{|frame| avoid.any?{|n| n == frame[:id]}}.each do |frame|
  text = frame[:text]
  data = frame[:data]
  owner = frame[:owner]
  frameBit = "  #{frame[:id]}:"
  if text != nil then
    textBit = "text = #{text.inspect}"
  end
  if data != nil then
    dataBit = "data = [[#{data.inspect}]]"
  end
  if owner != nil then
    ownerBit = "owner = [[#{owner.inspect}]]"
  end
  puts [frameBit, ownerBit, textBit, dataBit].reject{|i| i == nil}.join(" ")
end
puts "}"