Module: DTAS::Player::ClientHandler

Includes:
XS
Included in:
DTAS::Player
Defined in:
lib/dtas/player/client_handler.rb

Overview

:nodoc:

Instance Method Summary collapse

Methods included from XS

#xs

Instance Method Details

#__bp_prev_next(io, msg, cur, bp) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 618

def __bp_prev_next(io, msg, cur, bp)
  case type = msg[1]
  when nil, "track"
    bp.keep_if(&:track?)
  when "pregap"
    bp.keep_if(&:pregap?)
  when "subindex" # any subindex
    bp.keep_if(&:subindex?)
  when /\A\d+\z/ # exact subindex match
    si = type.to_i
    bp.keep_if { |ci| ci.index == si }
  when "any" # anything goes
  else
    return io.emit("INVALID TYPE")
  end
  fmt = cur.format
  case msg[0]
  when "next"
    ds = __current_decoded_samples
    bp.each do |ci|
      next if ci.offset_samples(fmt) < ds
      seek_internal(cur, ci.offset)
      return io.emit("OK")
    end
    # go to the next (real) track if not found
    __current_drop
  when "prev"
    os = cur.offset_samples # where we currently started
    bp.reverse_each do |ci|
      next if ci.offset_samples(fmt) >= os
      seek_internal(cur, ci.offset)
      return io.emit("OK")
    end
    # offset may be nil/zero if we couldn't find a previous breakpoint
    seek_internal(cur, '0')
  end
  io.emit("OK")
end

#__buf_reset(buf) ⇒ Object

buf is always @sink_buf for now



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# File 'lib/dtas/player/client_handler.rb', line 313

def __buf_reset(buf) # buf is always @sink_buf for now
  @srv.wait_ctl(buf, :ignore)
  buf.buf_reset
  @srv.wait_ctl(buf, :wait_readable)
end

#__current_decoded_samples ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 195

def __current_decoded_samples
  initial = @current.offset_samples
  decoded = @format.bytes_to_samples(bytes_decoded)
  decoded = out_samples(decoded, @format, @current.format)
  initial + decoded
end

#__current_requeue ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 202

def __current_requeue
  return unless @current

  # no need to requeue if we're already due to die
  return if @current.requeued
  @current.requeued = true

  dst = @current.dst
  # prepare to seek to the desired point based on the number of bytes which
  # passed through dst buffer we want the offset for the @current file,
  # which may have a different rate than our internal @format
  if @current.respond_to?(:infile)
    # this offset in the @current.format (not player @format)
    @queue.unshift([ @current.infile, "#{__current_decoded_samples}s" ])
  else
    # DTAS::Source::Cmd (hash), just rerun it
    @queue.unshift(@current.to_hsh)
  end
  # We also want to hard drop the buffer so we do not get repeated audio.
  __buf_reset(dst)
end

#__seek_offset_adj(dir, offset) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 184

def __seek_offset_adj(dir, offset)
  if offset.sub!(/s\z/, '')
    offset = offset.to_i
  else # time
    offset = @current.format.hhmmss_to_samples(offset)
  end
  n = __current_decoded_samples + (dir * offset)
  n = 0 if n < 0
  "#{n}s"
end

#__sink_activate(sink) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 70

def __sink_activate(sink)
  return if sink.pid
  @targets.concat(sink.spawn(@format))
  @targets.sort_by! { |t| t.sink.prio }
end

#__sink_snapshot(sink) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 111

def __sink_snapshot(sink)
  [ sink.command, sink.env, sink.pipe_size ].inspect
end

#__sink_switch(sink) ⇒ Object

called to activate/deactivate a sink



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# File 'lib/dtas/player/client_handler.rb', line 88

def __sink_switch(sink)
  if sink.active
    if @current
      # maybe it's still alive for now, but it's just being killed
      # do not reactivate it until we've reaped it
      if sink.pid
        drop_sink(sink)

        # we must restart @current if there's a moment we're target-less:
        __current_requeue unless @targets[0]
      else
        __sink_activate(sink)
      end
    end
  else
    drop_sink(sink)
  end
  # if we change any sinks, make sure the event loop watches it for
  # readability again, since we new sinks should be writable, and
  # we've stopped waiting on killed sinks
  @srv.wait_ctl(@sink_buf, :wait_readable)
end

#_tl_skip ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 535

def _tl_skip
  @queue.clear
  __current_drop
end

#active_sinks ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 267

def active_sinks
  sinks = @targets.map(&:sink)
  sinks.uniq!
  sinks
end

#adjust_numeric(io, obj, k, v) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 18

def adjust_numeric(io, obj, k, v)
  negate = !!v.sub!(/\A-/, '')
  case v
  when %r{\A\+?\d*\.\d+\z}
    num = v.to_f
  when %r{\A\+?\d+\z}
    num = v.to_i
  else
    return io.emit("ERR #{k}=#{v} must be a float")
  end
  num = -num if negate

  if k.sub!(/\+\z/, '') # increment existing
    num += obj.__send__(k)
  elsif k.sub!(/-\z/, '') # decrement existing
    num = obj.__send__(k) - num
  # else # normal assignment
  end
  obj.__send__("#{k}=", num)
  true
end

#bytes_decoded(src = @current) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 179

def bytes_decoded(src = @current)
  bytes = src.dst.bytes_xfer - src.dst_zero_byte
  bytes = bytes < 0 ? 0 : bytes # maybe negative in case of sink errors
end

#chdir_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 503

def chdir_handler(io, msg)
  msg.size == 1 or return io.emit("ERR usage: cd DIRNAME")
  begin
    Dir.chdir(msg[0])
  rescue => e
    return io.emit("ERR chdir: #{e.message}")
  end
  # wall(%W(cd msg[0])) # should we broadcast this?
  io.emit("OK")
end

#cue_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 657

def cue_handler(io, msg)
  cur = @current
  if cur.respond_to?(:cuebreakpoints)
    bp = cur.cuebreakpoints
    case msg[0]
    when nil
      tmp = { "infile" => cur.infile, "cue" => bp.map(&:to_hash) }
      io.emit(tmp.to_yaml)
    when "next", "prev"
      return __bp_prev_next(io, msg, cur, bp)
    when "goto"
      index = msg[1] or return io.emit("NOINDEX")
      ci = bp[index.to_i] or return io.emit("BADINDEX")
      seek_internal(cur, ci.offset)
      return io.emit("OK")
    end
  else
    io.emit("NOCUE")
  end
end

#current_expect_samples(in_samples) ⇒ Object

returns the number of samples we expect from the source this takes into account sample rate differences between the source and internal player format



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# File 'lib/dtas/player/client_handler.rb', line 234

def current_expect_samples(in_samples) # @current.samples
  out_samples(in_samples, @current.format, @format)
end

#current_handler(io, msg) ⇒ Object

show current info about what’s playing returns non-blocking iterator retval



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# File 'lib/dtas/player/client_handler.rb', line 275

def current_handler(io, msg)
  tmp = {}
  if @current
    tmp["current"] = s = @current.to_hsh
    s["spawn_at"] = @current.spawn_at
    s["pid"] = @current.pid

    # this offset and samples in the player @format (not @current.format)
    decoded = @format.bytes_to_samples(bytes_decoded)
    if @current.respond_to?(:infile)
      initial = tmp["current_initial"] = @current.offset_samples
      initial = out_samples(initial, @current.format, @format)
      tmp["current_expect"] = current_expect_samples(s["samples"])
      s["format"] = @current.format.to_hash.delete_if { |_,v| v.nil? }
    else
      initial = 0
      tmp["current_expect"] = nil
      s["format"] = @format.to_hash.delete_if { |_,v| v.nil? }
    end
    tmp["current_offset"] = initial + decoded
  end
  tmp["current_inflight"] = @sink_buf.inflight
  tmp["format"] = @format.to_hash.delete_if { |_,v| v.nil? }
  tmp["bypass"] = @bypass.sort!
  tmp["paused"] = @paused
  rg = @rg.to_hsh
  tmp["rg"] = rg unless rg.empty?
  if @targets[0]
    sinks = active_sinks
    tmp["sinks"] = sinks.map! do |sink|
      h = sink.to_hsh
      h["pid"] = sink.pid
      h
    end
  end
  io.emit(tmp.to_yaml)
end

#do_pause ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 336

def do_pause
  return if @paused
  wall("pause")
  @paused = true
  __current_requeue
end

#do_play ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 343

def do_play
  # no wall, next_source will wall on new track
  @paused = false
  return if @current
  n = _next
  unless n
    @tl.reset
    n = _next
  end
  next_source(n)
end

#do_play_pause ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 355

def do_play_pause
  @paused ? do_play : do_pause
end

#do_seek(io, offset) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 369

def do_seek(io, offset)
  if @current
    if @current.respond_to?(:infile)
      begin
        if offset.sub!(/\A\+/, '')
          offset = __seek_offset_adj(1, offset)
        elsif offset.sub!(/\A-/, '')
          offset = __seek_offset_adj(-1, offset)
        # else: pass to sox directly
        end
      rescue ArgumentError
        return io.emit("ERR bad time format")
      end
      seek_internal(@current, offset)
    else
      return io.emit("ERR unseekable")
    end
  elsif @paused
    case file = @queue[0]
    when String
      @queue[0] = [ file, offset ]
    when Array
      file[1] = offset
    else
      return io.emit("ERR unseekable")
    end
  # unpaused case... what do we do?
  end
  io.emit("OK")
end

#drop_sink(sink) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 76

def drop_sink(sink)
  @targets.delete_if do |t|
    if t.sink == sink
      drop_target(t)
      true
    else
      false
    end
  end
end

#env_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 441

def env_handler(io, msg)
  if msg.empty?
    # this may fail for large envs due to SEQPACKET size restrictions
    # do we care?
    env = ENV.map do |k,v|
      "#{Shellwords.escape(k)}=#{Shellwords.escape(v)}"
    end.join(' ')
    return io.emit(env)
  end
  msg.each do |kv|
    case kv
    when %r{\A([^=]+)=(.*)\z}
      ENV[$1] = $2
    when %r{\A([^=]+)#}
      ENV.delete($1)
    else
      return io.emit("ERR bad env")
    end
  end
  io.emit("OK")
end

#format_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 406

def format_handler(io, msg)
  new_fmt = @format.dup
  msg.each do |kv|
    k, v = kv.split(/=/, 2)
    case k
    when "type"
      new_fmt.valid_type?(v) or return io.emit("ERR invalid file type")
      new_fmt.type = v
    when "channels", "bits", "rate"
      case v
      when "bypass"
        @bypass << k unless @bypass.include?(k)
      else
        rv = set_uint(io, kv, v, false) { |u| new_fmt.__send__("#{k}=", u) }
        rv == true or return rv
        @bypass.delete(k)
      end
    when "endian"
      new_fmt.valid_endian?(v) or return io.emit("ERR invalid endian")
      new_fmt.endian = v
    end
  end

  bypass_match!(new_fmt, @current.format) if @current

  if new_fmt != @format
    restart_pipeline # calls __current_requeue

    # we must assign this after __current_requeue since __current_requeue
    # relies on the old @format for calculation
    format_update!(new_fmt)
  end
  io.emit("OK")
end

#out_samples(in_samples, infmt, outfmt) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 224

def out_samples(in_samples, infmt, outfmt)
  in_rate = infmt.rate
  out_rate = outfmt.rate
  return in_samples if in_rate == out_rate # easy!
  (in_samples * out_rate / in_rate.to_f).round
end

#play_pause_handler(io, command) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 325

def play_pause_handler(io, command)
  prev = @paused
  __send__("do_#{command}")
  io.emit({
    "paused" => {
      "before" => prev,
      "after" => @paused,
    }
  }.to_yaml)
end

#restart_pipeline ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 400

def restart_pipeline
  return if @paused
  __current_requeue
  stop_sinks
end

#rg_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 238

def rg_handler(io, msg)
  return io.emit(@rg.to_hsh.to_yaml) if msg.empty?
  before = @rg.to_hsh
  msg.each do |kv|
    k, v = kv.split(/=/, 2)
    case k
    when "mode"
      case v
      when "off"
        @rg.mode = nil
      else
        DTAS::RGState::RG_MODE.include?(v) or
          return io.emit("ERR rg mode invalid")
        @rg.mode = v
      end
    when "fallback_track"
      rv = set_bool(io, kv, v) { |b| @rg.fallback_track = b }
      rv == true or return rv
    when %r{(?:gain_threshold|norm_threshold|
            preamp|norm_level|fallback_gain)[+-]?\z}x
      rv = adjust_numeric(io, @rg, k, v)
      rv == true or return rv
    end
  end
  after = @rg.to_hsh
  __current_requeue if before != after
  io.emit("OK")
end

#seek_internal(cur, offset) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 359

def seek_internal(cur, offset)
  if cur.requeued
    @queue[0][1] = offset
  else
    @queue.unshift([ cur.infile, offset ])
    cur.requeued = true
    __buf_reset(cur.dst) # trigger EPIPE
  end
end

#set_bool(io, kv, v) ⇒ Object

returns true on success, wait_ctl arg on error



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# File 'lib/dtas/player/client_handler.rb', line 8

def set_bool(io, kv, v)
  case v
  when "false" then yield(false)
  when "true" then yield(true)
  else
    return io.emit("ERR #{kv} must be true or false")
  end
  true
end

#set_int(io, kv, v, null_ok) ⇒ Object

returns true on success, wait_ctl arg on error



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# File 'lib/dtas/player/client_handler.rb', line 41

def set_int(io, kv, v, null_ok)
  case v
  when %r{\A-?\d+\z}
    yield(v.to_i)
  when ""
    null_ok or return io.emit("ERR #{kv} must be defined")
    yield(nil)
  else
    return io.emit("ERR #{kv} must an integer")
  end
  true
end

#set_uint(io, kv, v, null_ok) ⇒ Object

returns true on success, wait_ctl arg on error



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# File 'lib/dtas/player/client_handler.rb', line 55

def set_uint(io, kv, v, null_ok)
  case v
  when %r{\A\d+\z}
    yield(v.to_i)
  when %r{\A0x[0-9a-fA-F]+\z}i # hex
    yield(v.to_i(16))
  when ""
    null_ok or return io.emit("ERR #{kv} must be defined")
    yield(nil)
  else
    return io.emit("ERR #{kv} must an non-negative integer")
  end
  true
end

#sink_handler(io, msg) ⇒ Object

returns a wait_ctl arg



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# File 'lib/dtas/player/client_handler.rb', line 116

def sink_handler(io, msg)
  name = msg[1]
  case msg[0]
  when "ls"
    io.emit(xs(@sinks.keys.sort))
  when "rm"
    sink = @sinks.delete(name) or return io.emit("ERR #{name} not found")
    drop_sink(sink)
    io.emit("OK")
  when "ed"
    sink = @sinks[name] || (new_sink = DTAS::Sink.new)

    # allow things that look like audio device names ("hw:1,0" , "/dev/dsp")
    # or variable names.
    sink.valid_name?(name) or return io.emit("ERR sink name invalid")

    sink.name = name
    active_before = sink.active
    before = __sink_snapshot(sink)

    # multiple changes may be made at once
    msg[2..-1].each do |kv|
      k, v = kv.split(/=/, 2)
      case k
      when %r{\Aenv\.([^=]+)\z}
        sink.env[$1] = v
      when %r{\Aenv#([^=]+)\z}
        v == nil or return io.emit("ERR unset env has no value")
        sink.env.delete($1)
      when "prio"
        rv = set_int(io, kv, v, false) { |i| sink.prio = i }
        rv == true or return rv
        @targets.sort_by! { |t| t.sink.prio } if sink.active
      when "nonblock", "active"
        rv = set_bool(io, kv, v) { |b| sink.__send__("#{k}=", b) }
        rv == true or return rv
      when "pipe_size"
        rv = set_uint(io, kv, v, false) { |u| sink.pipe_size = u }
        rv == true or return rv
      when "command" # nothing to validate, this could be "rm -rf /" :>
        sink.command = v.empty? ? DTAS::Sink::SINK_DEFAULTS["command"] : v
      end
    end

    @sinks[name] = new_sink if new_sink # no errors? it's a new sink!
    after = __sink_snapshot(sink)

    # start or stop a sink if its active= flag changed.  Additionally,
    # account for a crashed-but-marked-active sink.  The user may have
    # fixed the command to not crash it.
    if (active_before != sink.active) ||
       (sink.active && (!sink.pid || before != after))
      __sink_switch(sink)
    end
    io.emit("OK")
  when "cat"
    sink = @sinks[name] or return io.emit("ERR #{name} not found")
    io.emit(sink.to_hsh.to_yaml)
  else
    io.emit("ERR unknown sink op #{msg[0]}")
  end
end

#skip_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 319

def skip_handler(io, msg)
  __current_drop
  wall("skip")
  io.emit("OK")
end

#source_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 463

def source_handler(io, msg)
  map = @source_map
  op = msg.shift
  if op == "ls"
    s = map.keys.sort { |a,b| map[a].tryorder <=> map[b].tryorder }
    return io.emit(s.join(' '))
  end

  name = msg.shift
  src = map[name] or return io.emit("ERR non-existent source name")
  case op
  when "cat"
    io.emit(src.to_source_cat.to_yaml)
  when "ed"
    before = src.to_state_hash
    sd = src.source_defaults
    msg.each do |kv|
      k, v = kv.split(/=/, 2)
      case k
      when "command"
        src.command = v.empty? ? sd[k] : v
      when %r{\Aenv\.([^=]+)\z}
        src.env[$1] = v
      when %r{\Aenv#([^=]+)\z}
        v == nil or return io.emit("ERR unset env has no value")
        src.env.delete($1)
      when "tryorder"
        rv = set_int(io, kv, v, true) { |i| src.tryorder = i || sd[k] }
        rv == true or return rv
        source_map_reload
      end
    end
    after = src.to_state_hash
    __current_requeue if before != after && @current.class == src.class
    io.emit("OK")
  else
    io.emit("ERR unknown source op")
  end
end

#state_file_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 514

def state_file_handler(io, msg)
  case msg.shift
  when "dump"
    dest = msg.shift
    if dest
      sf = DTAS::StateFile.new(dest, false)
    elsif @state_file
      sf = @state_file
      dest = sf.path
    else
      return io.emit("ERR no state file configured")
    end
    begin
      sf.dump(self)
    rescue => e
      return io.emit("ERR dumping to #{xs(Array(dest))} #{e.message}")
    end
  end
  io.emit("OK")
end

#tl_handler(io, msg) ⇒ Object 



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# File 'lib/dtas/player/client_handler.rb', line 540

def tl_handler(io, msg)
  case msg.shift
  when "add"
    path = msg.shift
    after_track_id = msg.shift
    after_track_id = after_track_id.to_i if after_track_id
    case set_as_current = msg.shift
    when "true" then set_as_current = true
    when "false", nil then set_as_current = false
    else
      return io.emit("ERR tl add PATH [after_track_id] [true|false]")
    end
    begin
      track_id = @tl.add_track(path, after_track_id, set_as_current)
    rescue ArgumentError => e
      return io.emit("ERR #{e.message}")
    end

    _tl_skip if set_as_current # if @current is playing, it will restart soon

    # start playing if we're currently idle
    next_source(_next) unless need_to_queue
    io.emit("#{track_id}")
  when "repeat"
    case msg.shift
    when "true" then @tl.repeat = true
    when "false" then @tl.repeat = false
    when "1" then @tl.repeat = 1
    when nil
      return io.emit("repeat #{@tl.repeat.to_s}")
    end
    io.emit("OK")
  when "remove"
    track_id = msg.shift or return io.emit("ERR track_id not specified")
    track_id = track_id.to_i
    @tl.remove_track(track_id) or return io.emit("MISSING")

    # skip if we're removing the currently playing track
    if @current && @current.respond_to?(:infile) &&
       @current.infile.object_id == track_id
      _tl_skip
    end
    # drop it from the queue, too, in case it just got requeued or paused
    @queue.delete_if { |t| Array === t && t[0].object_id == track_id }
    io.emit("OK")
  when "get"
    res = @tl.get_tracks(msg.map!(&:to_i))
    res.map! { |tid, file| "#{tid}=#{file ? Shellwords.escape(file) : ''}" }
    io.emit("#{res.size} #{res.join(' ')}")
  when "tracks"
    tracks = @tl.tracks
    io.emit("#{tracks.size} " << tracks.map!(&:to_s).join(' '))
  when "goto"
    track_id = msg.shift or return io.emit("ERR track_id not specified")
    offset = msg.shift # may be nil
    if @tl.go_to(track_id.to_i, offset)
      _tl_skip
      next_source(_next) unless need_to_queue
      io.emit("OK")
    else
      io.emit("MISSING")
    end
  when "current"
    path = @tl.cur_track
    io.emit(path ? path : "NONE")
  when "current-id"
    path = @tl.cur_track
    io.emit(path ? path.object_id.to_s : "NONE")
  when "next"
    _tl_skip
    io.emit("OK")
  when "prev"
    @tl.previous!
    _tl_skip
    io.emit("OK")
  end
end