public void When_BooleanParameter_Expect_DirectAccess()
        {
            // Create voltage source
            var s = new VoltageSwitch("SW 1");
            var p = s.Parameters;

            // Check on
            s.SetParameter("on", true);
            Assert.AreEqual(true, p.ZeroState);

            // Check off
            s.SetParameter("off", true);
            Assert.AreEqual(false, p.ZeroState);
        }
        /// <summary>
        /// Generates a voltage switch.
        /// </summary>
        /// <param name="name">Name of voltage switch to generate.</param>
        /// <param name="parameters">Parameters for voltage switch.</param>
        /// <param name="context">Reading context.</param>
        /// <returns>
        /// A new voltage switch.
        /// </returns>
        protected IEntity GenerateVoltageSwitch(string name, ParameterCollection parameters, ICircuitContext context)
        {
            if (parameters.Count < 5)
            {
                context.Result.Validation.Add(new ValidationEntry(ValidationEntrySource.Reader, ValidationEntryLevel.Warning, "Wrong parameter count for voltage switch", parameters.LineInfo));
                return(null);
            }

            string modelName = parameters.Get(4).Image;

            var model = context.ModelsRegistry.FindModel(modelName);

            if (model.Entity is VSwitchModel)
            {
                BehavioralResistor resistor = new BehavioralResistor(name);
                Model resistorModel         = model;
                context.CreateNodes(resistor, parameters.Take(BehavioralResistor.BehavioralResistorPinCount));
                var vSwitchModelParameters = resistorModel.Parameters as VSwitchModelParameters;

                double vOff = vSwitchModelParameters.OffVoltage;
                double rOff = vSwitchModelParameters.OffResistance;
                double vOn  = vSwitchModelParameters.OnVoltage;
                double rOn  = vSwitchModelParameters.OnResistance;

                string vc            = $"v({parameters.Get(2)}, {parameters.Get(3)})";
                double lm            = Math.Log(Math.Sqrt(rOn * rOff));
                double lr            = Math.Log(rOn / rOff);
                double vm            = (vOn + vOff) / 2.0;
                double vd            = vOn - vOff;
                string resExpression = GetVSwitchExpression(vOff, rOff, vOn, rOn, vc, lm, lr, vm, vd);

                resistor.Parameters.Expression  = resExpression;
                resistor.Parameters.ParseAction = (expression) =>
                {
                    var parser = new ExpressionParser(context.Evaluator.GetEvaluationContext(null), false, context.CaseSensitivity);
                    return(parser.Resolve(expression));
                };

                context.SimulationPreparations.ExecuteActionAfterSetup(
                    (simulation) =>
                {
                    if (context.ModelsRegistry is StochasticModelsRegistry stochasticModelsRegistry)
                    {
                        resistorModel = stochasticModelsRegistry.ProvideStochasticModel(name, simulation, model);

                        if (!context.Result.FindObject(resistorModel.Name, out _))
                        {
                            stochasticModelsRegistry.RegisterModelInstance(resistorModel);
                        }
                    }

                    vOff          = vSwitchModelParameters.OffVoltage;
                    rOff          = vSwitchModelParameters.OffResistance;
                    vOn           = vSwitchModelParameters.OnVoltage;
                    rOn           = vSwitchModelParameters.OnResistance;
                    lm            = Math.Log(Math.Sqrt(rOn * rOff));
                    lr            = Math.Log(rOn / rOff);
                    vm            = (vOn + vOff) / 2.0;
                    vd            = vOn - vOff;
                    resExpression = GetVSwitchExpression(vOff, rOff, vOn, rOn, vc, lm, lr, vm, vd);
                    resistor.Parameters.Expression  = resExpression;
                    resistor.Parameters.ParseAction = (expression) =>
                    {
                        var parser = new ExpressionParser(context.Evaluator.GetEvaluationContext(simulation), false, context.CaseSensitivity);
                        return(parser.Resolve(expression));
                    };
                });
                return(resistor);
            }

            VoltageSwitch vsw = new VoltageSwitch(name);

            context.CreateNodes(vsw, parameters);

            context.SimulationPreparations.ExecuteActionBeforeSetup((simulation) =>
            {
                context.ModelsRegistry.SetModel(
                    vsw,
                    simulation,
                    parameters.Get(4),
                    $"Could not find model {parameters.Get(4)} for voltage switch {name}",
                    (Context.Models.Model model2) => { vsw.Model = model2.Name; },
                    context.Result);
            });

            // Optional ON or OFF
            if (parameters.Count == 6)
            {
                switch (parameters.Get(5).Image.ToLower())
                {
                case "on":
                    vsw.SetParameter("on", true);
                    break;

                case "off":
                    vsw.SetParameter("off", true);
                    break;

                default:
                    context.Result.Validation.Add(new ValidationEntry(ValidationEntrySource.Reader, ValidationEntryLevel.Warning, "ON or OFF expected", parameters.LineInfo));
                    return(vsw);
                }
            }
            else if (parameters.Count > 6)
            {
                context.Result.Validation.Add(new ValidationEntry(ValidationEntrySource.Reader, ValidationEntryLevel.Warning, "Too many parameters for voltage switch", parameters.LineInfo));
                return(vsw);
            }

            return(vsw);
        }