mpd.rb

require 'ruby-mpd'

class MPD
  def idle(*subsystems)
    self.send_command('idle',*subsystems)
  end

  def async_idle
    raise ConnectionError, "Not connected to the server!" if !@socket
    @mutex.synchronize do
      begin
        @socket.puts convert_command('idle', 'mixer')
      rescue Errno::EPIPE
        reconnect
        retry
      end
   end
 end

 def noidle
   @idle_lock ||= Mutex.new

   EM.defer do
     @idle_lock.synchronize do
       self.send_command 'noidle'
       begin
         yield self
       rescue MPD::ServerArgumentError => e
         p e
       rescue MPD::NotPlaying => e
         p e
       end
       self.async_idle
     end
   end
 end

 def noidle_sync
   @idle_lock ||= Mutex.new

   @idle_lock.synchronize do
     self.send_command 'noidle'
     begin
       yield self
     rescue MPD::ServerArgumentError => e
       p e
     rescue MPD::NotPlaying => e
       p e
     end
     self.async_idle
   end
 end

 class Song
   def as_json
     {title: title, artist: artist, album: album}
   end
   def to_json(*a)
     as_json.to_json(*a)
   end
 end
end