using System;
using System.ComponentModel;
using System.Reflection;

namespace WayneChina_IcCardReader_SinoChem
{
    public static class Extensions
    {
        public static void SetPropertyValue(this object target, string propertyName, string propertyValue)
        {
            PropertyInfo propInfo = target.GetType().GetProperty(propertyName);
            Type propType = propInfo.PropertyType;

            if (propType.IsGenericType && propType.GetGenericTypeDefinition().Equals(typeof(Nullable<>)))
            {
                if (propertyValue == null)
                {
                    propInfo.SetValue(target, null, null);
                    return;
                }

                propType = new NullableConverter(propInfo.PropertyType).UnderlyingType;
            }

            propInfo.SetValue(target, Convert.ChangeType(propertyValue, propType), null);
        }

        public static byte[] Crc16Ccitt(this byte[] bytes)
        {
            const ushort poly = 4129;
            ushort[] table = new ushort[256];
            ushort initialValue = 0xFFFF;
            ushort temp, a;
            ushort crc = initialValue;

            for (int i = 0; i < table.Length; ++i)
            {
                temp = 0;
                a = (ushort)(i << 8);
                for (int j = 0; j < 8; ++j)
                {
                    if (((temp ^ a) & 0x8000) != 0)
                        temp = (ushort)((temp << 1) ^ poly);
                    else
                        temp <<= 1;
                    a <<= 1;
                }
                table[i] = temp;
            }

            for (int i = 0; i < bytes.Length; ++i)
            {
                crc = (ushort)((crc << 8) ^ table[((crc >> 8) ^ (0xFF & bytes[i]))]);
            }

            return BitConverter.GetBytes(crc);
        }
    }
}