using System.Threading;
using Microsoft.SPOT.Hardware;

namespace HWModules
{
    //TODO P2 need a method to setup ADC registers
    public class ADC2485 : I2CPortBase
    {
        private static I2CDevice.I2CTransaction[] xActions2485 = new I2CDevice.I2CTransaction[2];

        private static byte[] sampleBytes = new byte[4];
        private static byte[] convertBytes = new byte[4];
        private static byte[] mode0 = new byte[1] { 0x00 };//External input, 50 and 60 Hz filter, 1X speed
        private static byte[] mode4 = new byte[1] { 0x04 };//External input, 60 Hz filter, 1X speed

        private static int xActionReturn = 0;

        private static int value = int.MaxValue;

        public ADC2485(I2CDevice.Configuration config, int slotNumber) : base (config, slotNumber)
        {}
            
        public int readValue()
        {
            // create write buffer, send 2485 mode command
            xActions2485[0] = CreateWriteTransaction(mode4);

            // create read buffer to read the returned data
            xActions2485[1] = CreateReadTransaction(sampleBytes);

            Thread.Sleep(200);
            xActionReturn = Execute(xActions2485, 1000);
 
            if (xActionReturn == 0)
            {
                EngrLogger.writeToColumns("Error executing 2485 Transaction = " + xActionReturn.ToString());
                return (int.MaxValue);
            }
            else
            {
                //Debug.Print(sampleBytes[0].ToString() + " " + sampleBytes[1].ToString() + " " +
                //            sampleBytes[2].ToString() + " " + sampleBytes[3].ToString());

                if ((sampleBytes[0] >= (byte)0xC0) || (sampleBytes[0] < (byte)0x40))
                {
                    EngrLogger.writeToColumns("2485 Sample out of range");
                    return (int.MaxValue);
                }
                else
                {
                    convertBytes[0] = sampleBytes[3];
                    convertBytes[1] = sampleBytes[2];
                    convertBytes[2] = sampleBytes[1];
                    convertBytes[3] = sampleBytes[0];
                    value = GHI.Utilities.Arrays.ExtractInt32(convertBytes, 0);
                    //Debug.Print("Reversed bytes value = " + value.ToString());
                    return (value);
                }
            }
        }
    }
}