DBus

<node>
  <interface name="com.joinc.JMusic.Manager">
    <method name="GetAllList">
    </method>
    <method name="AddList">
        <arg name="filename" type="s" direction="in"/>
    </method>
    <method name="DelList">
        <arg name="filename" type="s" direction="in"/>
    </method>
  </interface>
  <interface name="com.joinc.JMusic.Control">
    <signal name="start">
        <arg name="state" type="i"/>
        <arg name="error" type="s"/>
    </signal>
  </interface>
</node>

# gem install ruby-dbus
# gem install getopt

require 'dbus' 
require 'json'

class MusicPlayer < DBus::Object
    @music_queue = nil
    def initialize arg
        super(arg)
        @music_queue = Array.new
    end

    # Player 인터페이스를 추가한다. 
    # play와 playAll 두개의 메서드와
    # MusicEnding 시그널을 가지고 있다.
    dbus_interface "co.kr.joinc.jmusic.Player" do
        # string 타입의 매개변수를 받는다.
        # string을 반환한다.
        dbus_method :play, "in name:s, out outstr:s" do |name|
            puts "Play Music : #{name}"
            sleep(1)
            ["#{name} ending..."]
        end

        # 재생 대기열의 모든 곡을 재생한다.
        # 재생 시작과 재생 끝에 대해서 시그널을 전송한다.
        dbus_method :playAll  do
            r = Random.new
            @music_queue.each do | v |
                MusicStart v
                playTime = r.rand(3...6)
                puts "Play Music : #{v}"
                sleep(playTime)
                MusicEnding v, playTime
            end
        end

        # 신경쓰지 말자.
        dbus_method :stop do 
        end

        # 시그널
        dbus_signal :MusicEnding, "toto:s, time:u"
        dbus_signal :MusicStart, "toto:s, time:u"
    end

    # 재생 대기열을 관리한다. 
    dbus_interface "co.kr.joinc.jmusic.Manager" do
        # 재생 대기열에 곡을 추가한다.
        dbus_method :add, "in name:s" do |name|
            @music_queue.push(name)
            puts "#{name} add Queue!!"
        end
        # 재생 대기열의 모든 곡을 출력한다.
        dbus_method :getList,"out data:s" do
            data = @music_queue.to_json
            [data]
        end
    end
end

bus = DBus::SessionBus.instance
service = bus.request_service("co.kr.joinc.jmusic")
myobj = MusicPlayer.new("/co/kr/joinc/jmusic") 
service.export(myobj)

puts "listening"
main = DBus::Main.new
main << bus
main.run

require 'dbus'
require 'getopt/long'
require 'json'

class Player
    @session_bus = nil
    @player = nil
    @intro = nil
    @manager_iface = nil
    @player_iface = nil

    def initialize
        @session_bus = DBus::SessionBus.instance
        service = @session_bus.service("co.kr.joinc.jmusic")
        @player = service.object("/co/kr/joinc/jmusic")
        introspect
        # 두개의 인트페이스가 필요하다.
        @manager_iface = @player["co.kr.joinc.jmusic.Manager"]
        @player_iface = @player["co.kr.joinc.jmusic.Player"]

        playerSignal
    end

    def introspect
        @intro = @player.introspect
    end

    def showspec
        return @intro
    end

    def play name
        response = @player_iface.play name
        puts response
    end

    def playAll
        @player_iface.playAll
    end

    def add name
        puts "Add music #{name}"
        @manager_iface.add name
    end

    def getList 
        a = @manager_iface.getList
        return JSON.parse(a[0])
    end

    def playerSignal
        @player_iface.on_signal("MusicStart") do |name|
            puts "Music Play #{name}++"
        end
        @player_iface.on_signal("MusicEnding") do |name, time|
            puts "Music Ending #{name} (#{time})..."
        end
    end
end

opt = Getopt::Long.getopts(
    ["--add", "-a", Getopt::REQUIRED],
    ["--play", "-n", Getopt::REQUIRED],
    ["--playall", "-p", Getopt::BOOLEAN],
    ["--intro", "-i", Getopt::BOOLEAN],
    ["--list", "-l", Getopt::BOOLEAN]
)

myPlayer = Player.new

if opt['a']
    myPlayer.add(opt['a'])
elsif opt['n']
    myPlayer.play opt['n']
elsif opt['p']
    myPlayer.playAll
elsif opt['i']
    puts myPlayer.showspec
elsif opt['l']
    myPlayer.getList.each_with_index do | v, index |
        puts "#{index} : #{v}"
    end
end

# ruby music_player.rb -i | xmllint --format -
<?xml version="1.0"?>                                                                                                                         
<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN" "http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
<node>                                                                                                                                        
  <interface name="co.kr.joinc.jmusic.Player">                                                                                                
    <method name="play">                                                                                                                      
      <arg name="name" direction="in" type="s"/>                                                                                              
      <arg name="outstr" direction="out" type="s"/>
    </method>
    <method name="playAll">
</method>
    <method name="stop">
</method>
    <signal name="MusicEnding">
      <arg name="toto" type="s"/>
      <arg name="time" type="u"/>
    </signal>
    <signal name="MusicStart">
      <arg name="toto" type="s"/>
      <arg name="time" type="u"/>
    </signal>
  </interface>
  <interface name="co.kr.joinc.jmusic.Manager">
    <method name="add">
      <arg name="name" direction="in" type="s"/>
    </method>
    <method name="getList">
      <arg name="data" direction="out" type="s"/>
    </method>
  </interface>
</node>