using System;

namespace SWModules
{
    public class Utils
    {

        public static int getField(byte[] inBytes, byte token, int desiredField, ref byte[] returnField)
        {
            int currentField = 0;
            int returnFieldIndex = 0;
            bool inDesiredField;

            if (desiredField == 0)
                inDesiredField = true;
            else
                inDesiredField = false;

            Array.Clear(returnField, 0, returnField.Length);

            for (int i = 0; i < inBytes.Length; i++)
            {
                if ((inBytes[i] == token) && !inDesiredField)
                    currentField++;
                else if (currentField == desiredField)
                {
                    inDesiredField = true;
                    if ((inBytes[i] == token) || (inBytes[i] == 10) || (inBytes[i] == 13))
                        return (returnFieldIndex);
                    else
                    {
                        returnField[returnFieldIndex++] = inBytes[i];
                        if(returnFieldIndex > returnField.Length)
                            return returnFieldIndex;
                    }
                }
            }
            return (0);
        }

        /// <summary>
        /// Compares values in sequence for two byte arrays, and returns true if A = B for the subset that is identified.
        /// </summary>
        /// <param name="aBytes">Input Array to check</param>
        /// <param name="aOffset">Array offset to start comparison in A</param>
        /// <param name="bBytes">Second input array to check</param>
        /// <param name="bOffset">Array offset for second input</param>
        /// <param name="count">Number of bytes to compare</param>
        /// <returns></returns>
        public static bool CompareArray(byte[] aBytes, int aOffset, byte[] bBytes, int bOffset, int count)
        {
            if ((aBytes.Length < aOffset+count)||(bBytes.Length < bOffset+count))
                return false;
            for (int i = 0; i < count; i++)
            {
                if (aBytes[i + aOffset] != bBytes[bOffset + i])
                    return false;
            }

            return true;

        }

        public static uint SecondsSinceEpoch
        {
            get
            {
                TimeSpan t = DateTime.UtcNow - new DateTime(1970, 1, 1);
                return (uint)(t.Seconds + t.Minutes * 60 + t.Hours * 3600 + t.Days * 86400 );
            }
        }


    }

  
    public enum WfrState
      {
            Waiting = 0,
            GotResponse = 1,
            NotWaiting = -2,
            TimedOut = -1,
    }
}