using System;
using System.Globalization;
using System.Windows.Data;

namespace AIStudio.Wpf.DiagramDesigner
{
    public enum MathOperation
    {
        Add,
        Subtract,
        Multiply,
        Divide
    }

    public sealed class MathConverter : IValueConverter
    {
        public MathOperation Operation
        {
            get; set;
        }

        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            try
            {
                double value1 = System.Convert.ToDouble(value, CultureInfo.InvariantCulture);
                double value2 = System.Convert.ToDouble(parameter, CultureInfo.InvariantCulture);
                switch (Operation)
                {
                    case MathOperation.Add:
                        return value1 + value2;
                    case MathOperation.Divide:
                        return value1 / value2;
                    case MathOperation.Multiply:
                        return value1 * value2;
                    case MathOperation.Subtract:
                        return value1 - value2;
                    default:
                        return Binding.DoNothing;
                }
            }
            catch (FormatException)
            {
                return Binding.DoNothing;
            }
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            return Binding.DoNothing;
        }
    }
}
