// Copyright (c) 2017 schick Informatik
// Description: Helper class to convert database byte values to combobox Selected INdex int's 
//

using System;
using System.Windows.Data;
using System.Windows.Markup;

namespace ENI2.Util
{
    [ValueConversion(typeof(byte?), typeof(int))]
    public class ByteConverter : MarkupExtension, IValueConverter
    {
        #region MarkupExtension implementation

        private static ByteConverter _converter = null;

        public override object ProvideValue(IServiceProvider serviceProvider)
        {
            if (_converter == null)
            {
                _converter = new ByteConverter();
            }
            return _converter;
        }

        #endregion

        #region IValueConverter implementation

        public object Convert(object value, Type targetType, object parameter,
                          System.Globalization.CultureInfo culture)
        {
            int result = -1;
            if (value is byte?)
            {
                if (((byte?)value).HasValue)
                {
                    byte byteVal = (byte)value;
                    result = (int)byteVal;
                }
            }
            return result;
        }

        public object ConvertBack(object value, Type targetType, object parameter,
                                  System.Globalization.CultureInfo culture)
        {
            byte? result = null;
            if(value is int)
            {
                if ((int)value >= 0)
                {
                    int intValue = (int)value;
                    result = (byte)intValue;
                }
            }

            return result;
        }

        #endregion

    }
}