[MachineDecl(Name = "Jeskola Gain", ShortName = "Gain", Author = "Oskari Tammelin")]
    public class GainMachine : IBuzzMachine
    {
        IBuzzMachineHost host;

        public GainMachine(IBuzzMachineHost host)
        {
            this.host = host;
            Gain = new Interpolator();
            MachineState = new State();
        }

        [ParameterDecl(ResponseTime = 5, MaxValue = 127, DefValue = 80, Transformation = Transformations.Cubic, TransformUnityValue = 80, ValueDescriptor = Descriptors.Decibel)]
        public Interpolator Gain { get; private set; }

        [ParameterDecl(ValueDescriptions = new[] { "no", "yes" })]
        public bool Bypass { get; set; }

        public Sample Work(Sample s)
        {
            return Bypass ? s : s * Gain.Tick();
        }

        public class State : INotifyPropertyChanged
        {
            public State() { text = "here is state"; }  // NOTE: parameterless constructor is required by the xml serializer

            string text;
            public string Text
            {
                get { return text; }
                set
                {
                    text = value;
                    if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("Text"));
                }
            }

            public event PropertyChangedEventHandler PropertyChanged;
        }

        public State MachineState { get; set; }     // a property called 'MachineState' gets automatically saved in songs and presets
    }

    public class MachineGUIFactory : IMachineGUIFactory { public IMachineGUI CreateGUI(IMachineGUIHost host) { return new GainGUI(); } }
    public class GainGUI : UserControl, IMachineGUI
    {
        IMachine machine;
        GainMachine gainMachine;
        TextBox tb;

        public IMachine Machine
        {
            get { return machine; }
            set
            {
                machine = value;
                if (machine != null)
                {
                    gainMachine = (GainMachine)machine.ManagedMachine;
                    tb.SetBinding(TextBox.TextProperty, new Binding("Text") { Source = gainMachine.MachineState, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                }
            }
        }

        public GainGUI()
        {
            this.Content = tb = new TextBox() { Margin = new Thickness(0, 0, 0, 4) };
        }

    }