Put mp3s in folders based on id3 tags for artist and album. Create filenames based on disk #, track #, and title from id3 tags.

folderify_mp3s.rb

#!/usr/bin/env ruby
begin
  require 'fileutils'
  require 'id3tag'
  require 'pry'
  class FolderifyMp3s

    REGEX = /\(|\)|\/|\\/.freeze

    def call
      mp3s.each do |mp3|
        process_mp3(file: mp3)
      end
    end

    private

    def initialize(folder:, dest:, test_mode: true)
      @folder    = folder
      @dest      = dest
      @test_mode = test_mode
    end

    def mp3s
      Dir.entries(@folder).select do |filename|
        filename =~ /\.mp3\s*$/i
      end
    end

    def process_mp3(file:)
      tag = ID3Tag.read(File.open("#{@folder}/#{file}", 'rb'))
      begin
        debug_mp3(file: file, tag: tag) if @test_mode
        fn = "#{mp3_directory!(tag: tag)}/#{filename(tag: tag)}"
        raise "File already exists!!! #{fn}" if File.exist?(fn)

        FileUtils.mv(
          "#{@folder}/#{file}",
          fn,
          verbose: true,
          noop: @test_mode
        )
      rescue RuntimeError => e
        binding.pry
      end
    end

    def debug_mp3(file:, tag:)
      puts "\n---\n"
      puts "path: #{file}"
      puts "artist: #{tag.artist}"
      puts "album: #{tag.album}"
      puts "disk: #{disk(tag: tag)}"
      puts "track: #{track(tag: tag)}"
      puts "title: #{tag.title}"
    end

    def mp3_directory!(tag:)
      unless Dir.exist?("#{@dest}/#{artist(tag: tag)}")
        FileUtils.mkdir("#{@dest}/#{artist(tag: tag)}", noop: @test_mode)
      end
      unless Dir.exist?("#{@dest}/#{artist(tag: tag)}/#{album(tag: tag)}")
        FileUtils.mkdir(
          "#{@dest}/#{artist(tag: tag)}/#{album(tag: tag)}", noop: @test_mode
        )
      end
      "#{@dest}/#{artist(tag: tag)}/#{album(tag: tag)}"
    end

    def artist(tag:)
      if tag.artist.to_s.gsub(/^\s*$/, '') == ''
        'Unknown Artist'
      else
        tag.artist.gsub(REGEX, '')
      end
    end

    def album(tag:)
      if tag.album.to_s.gsub(/^\s*$/, '') == ''
        'Unknown Album'
      else
        tag.album.gsub(REGEX, '')
      end
    end

    def filename(tag:)
      [
        disk(tag: tag), track(tag: tag), tag.title
      ].compact.join(' - ').gsub(REGEX, '').chomp('.mp3') + '.mp3'
    end

    def disk(tag:)
      disk_or_track(num: tag.get_frame(:TPOS).content.to_s.split('/')[0])
    rescue RuntimeError
      nil
    end

    def track(tag:)
      disk_or_track(num: tag.track_nr.to_s.split('/')[0])
    end

    def disk_or_track(num:)
      return nil if num.to_i.zero?

      n
    end

  end

  if File.expand_path(__FILE__) == File.expand_path($PROGRAM_NAME)
    (1..5).each do |i|
      FolderifyMp3s.new(
        folder: "/mnt/media/plex/google-takeout/50gb/#{i}/Takeout/Google Play Music/Tracks",
        dest: '/mnt/media/plex/google-takeout/50gb/organized_music',
        test_mode: false
      ).call
    end
  end
rescue LoadError => e
  puts "LoadError: #{e.message}"
end

With Google Play Music being killed off, I used the Takeout process to get my music. All the decompressed archives put the music in one folder.

I made the move to Plex (https://www.plex.tv/), which put everything in an "Unknown Artist" category b/c the music was in one directory. This script worked pretty well to put things in an organized folder structure.

Things like movie soundtracks or albums where the "Artist" id3 tag was not consistent are still kinda a mess, but the bulk of my albums are looking good in the Plex environment.

Might follow-up to this gist with another script to try to make sense out of the soundtracks / albums with inconsistent artists.