EricaSynths Pico Drum Samples for Expert Sleepers Disting

erica.rb

# frozen_string_literal: true

require 'msgpack'
require 'net/http'
require 'uri'
require 'json'
require 'wavefile'
require 'fileutils'

DATA_ROOT = 'data'

class RawData
  def to_msgpack_ext
    raise NotImplementedError
  end

  def self.from_msgpack_ext(data)
    data
  end
end

MessagePack::DefaultFactory.register_type(0x1a, RawData)

def download_pack_list
  now           = Time.now.to_i
  pack_list_uri = URI("http://data.ericasynths.lv/picodrum/pack_list.json?_=#{now}")

  JSON.parse(Net::HTTP.get(pack_list_uri))
end

def download_pack(filename)
  pack_uri = URI("http://data.ericasynths.lv/picodrum/#{filename}")
  blob     = Net::HTTP.get(pack_uri)

  MessagePack.unpack(blob)
end

download_pack_list.each do |pack|
  puts "#{pack['file']} (v#{pack['version']})"

  pack_dir = pack['file'].sub('.bin', '') + "_v#{pack['version']}"
  data_dir = File.join(DATA_ROOT, pack_dir)

  FileUtils.mkdir_p(data_dir)

  playlist = <<~HEREDOC
      disting playlist v1
      -loop=0
      -gap=0
      -fadeIn=0
      -fadeOut=0
  HEREDOC

  download_pack(pack['file']).each do |sample|
    puts "-- #{sample['name']}"

    begin
      reader = WaveFile::Reader.new(StringIO.new(sample['data']))
    rescue => e
      puts "error: #{e.message}"
      next
    end

    wav_filepath = File.join(data_dir, sample['name'])
    dest_fmt     = WaveFile::Format.new(:mono, :pcm_16, 44100)

    WaveFile::Writer.new(wav_filepath, dest_fmt) do |writer|
      reader.each_buffer { |buffer| writer.write(buffer) }
    end

    playlist += "#{sample['name']}\n"
  end

  playlist_filepath = File.join(data_dir, 'playlist.txt')
  File.open(playlist_filepath, 'w') { |file| file.write(playlist) }
end

Gemfile

# frozen_string_literal: true

source "https://rubygems.org"

git_source(:github) {|repo_name| "https://github.com/#{repo_name}" }

gem 'msgpack'
gem 'wavefile'