enum MessageType {
    kMessageTypeHello = 1;
    kMessageTypeGoodbye = 2;
    kMessageTypeNotify = 10;
    kMessageTypeLoad = 20;
    kMessageTypePlay = 21;
    kMessageTypePause = 22;
//    kMessageTypePlayPause = 23;
    kMessageTypeSeek = 24;
    kMessageTypePrev = 25;
    kMessageTypeNext = 26;
    kMessageTypeVolume = 27;
    kMessageTypeShuffle = 28;
    kMessageTypeRepeat = 29;
    kMessageTypeQueue = 30;
    kMessageTypeVolumeDown = 31;
    kMessageTypeVolumeUp = 32;
    kMessageTypeAddToQueue = 33;
}
enum PlayStatus {
    kPlayStatusStop = 0;
    kPlayStatusPlay = 1;
    kPlayStatusPause = 2;
    kPlayStatusLoading = 3;
    kPlayStatusError = 4;
}
message Goodbye {
    required string reason = 1;
}
message State {
    optional string contextURI = 0x2;
    optional uint32 index = 0x3;
    optional uint32 position = 0x4;
    optional PlayStatus status = 0x5;

    optional uint64 timestamp = 0x7;
    optional string context_name = 0x8;
    optional uint32 duration = 0x9;
    optional uint32 data9 = 0xa;
    repeated uint64 data10 = 0xb;
    optional bool shuffle = 0xd;
    optional bool repeat = 0xe;

    optional string data12 = 0x14;
    optional uint32 data13 = 0x15;
    optional uint32 data14 = 0x18;
    optional uint32 data15 = 0x19;
    optional uint32 data16 = 0x1a;
    repeated QueuedTrack queued = 0x1b;
    message QueuedTrack {
        optional bytes  gid = 0x1;
        optional string local_uri = 0x2;
        optional uint32 data1 = 0x3;
    }
}

message Frame {
    required uint32 version = 1;
    required string source = 2;
    required string version_string = 3;
    required uint32 msgid = 4;
    required uint32 type = 5;

    required DeviceInfo device = 0x7;

    //required Goodbye goodbye = 0xb;
    optional State state = 0xc;

    optional uint32 position = 0xd;
    optional uint32 volume = 0xe;

    optional uint64 timestamp = 0x11;
    optional string destination = 0x12;

    message DeviceInfo {
        optional string version    = 0x1;
        required bool   active     = 0xa;
        required bool   foreground = 0xb;
        required uint32 volume     = 0xc;
        required string name       = 0xd;
        optional uint32 data15     = 0xe;
        required uint64 activeTime = 0xf;
        repeated Data17 data17     = 0x11;

        message Data17 {
            required uint32 data0 = 0x1;
            optional uint32 data1 = 0x2;
            repeated string data2 = 0x3;
        }
    }
}