using System;
using Microsoft.SPOT;

using System.Text;


namespace getFieldTest
{
    public class Program
    {

        private static StringBuilder msg = new StringBuilder("upengr,1,2,3");
        private static byte[] msgArray = new byte[64];

        public static void Main()
        {
            Array.Clear(msgArray, 0, msgArray.Length);
            Array.Copy(UTF8Encoding.UTF8.GetBytes(msg.ToString()), msgArray, msg.Length);

            Debug.Print(msg.ToString());
            getField(msgArray, (byte)',', 0);
            getField(msgArray, (byte)',', 1);
            getField(msgArray, (byte)',', 2);
            getField(msgArray, (byte)',', 3);

            msg.Clear();
            msg.Append("upengr");
            Debug.Print(msg.ToString());
            getField(msgArray, (byte)',', 0);
            msg.Append(",");
            getField(msgArray, (byte)',', 0);
        }

        private static StringBuilder returnArraySB = new StringBuilder(64);

        private static byte[] getField(byte[] inArray, byte token, int desiredField)
        {
            byte[] returnArray = new byte[64];

            int startIndex = 0;
            int endIndex = inArray.Length;
            int fieldNum = 0;

            bool gotField = false;

            for (int i = 0; i < inArray.Length; i++)
            {
                if (inArray[i] == token)
                {
                    if (desiredField == 0)
                    {
                        endIndex = i;
                        gotField = true;
                        break;
                    }
                    else
                    {
                        fieldNum = fieldNum + 1;
                        if (fieldNum == desiredField)
                        {
                            startIndex = i + 1;
                            endIndex = Array.IndexOf(inArray, token, startIndex);
                            if (endIndex < 0)
                                endIndex = inArray.Length;
                            gotField = true;
                            break;
                        }
                    }
                }
            }

            Array.Clear(returnArray, 0, returnArray.Length);
            if (gotField || (desiredField == 0))
                Array.Copy(inArray, startIndex, returnArray, 0, endIndex - startIndex);

            returnArraySB.Clear();
            returnArraySB.Append(UTF8Encoding.UTF8.GetChars(returnArray));
            Debug.Print(returnArraySB.ToString());
            return (returnArray);
        }
    }
}