using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace HengshanPaymentTerminal
{
    public static class HengshanExtensions
    {
        /// <summary>
        /// Converts a byte array, normally two bytes to an integer.
        /// e.g. byte array of 0x00 0x12 is converted to integer of 18. 
        /// </summary>
        /// <param name="source">The source byte array</param>
        /// <returns>integer value</returns>
        public static int ToInt32(this byte[] source)
        {
            var hexTarget = new StringBuilder(source.Length * 2);
            foreach (byte b in source)
                hexTarget.AppendFormat("{0:x2}", b);

            return int.Parse(hexTarget.ToString(), NumberStyles.HexNumber);
        }

        /// <summary>
        /// Converts a char array to an unsigned short integer.
        /// </summary>
        /// <param name="source">The source char array.</param>
        /// <returns>An unsigned short integer value.</returns>
        public static ushort ToUInt16(this char[] source)
        {
            var hexTarget = new StringBuilder(source.Length * 2);
            foreach (byte b in source)
                hexTarget.AppendFormat("{0:x2}", b);

            return UInt16.Parse(hexTarget.ToString(), NumberStyles.HexNumber);
        }

        public static byte ToByte(this string source)
        {
            return Convert.ToByte(Int16.Parse(source, NumberStyles.HexNumber));
        }

        public static ushort ToUInt16(this string source)
        {
            return UInt16.Parse(source, NumberStyles.HexNumber);
        }

        public static uint ToUInt32(this string source)
        {
            return UInt32.Parse(source, NumberStyles.HexNumber);
        }
    }
}