using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO.Ports;
using System.Text.RegularExpressions;
using Microsoft.Win32;

namespace TinyFPGA_VisualProgrammer
{
    public class SerialController
    {
        SerialPort mainSerial = new SerialPort();
        public List<string> sPortsList { get; private set; }
        public string comPortName { get; set; }

        public SerialController()
        {
            mainSerial.BaudRate = 9600;
            mainSerial.ReceivedBytesThreshold = 1;
            mainSerial.ReadBufferSize = 4096;
            mainSerial.WriteBufferSize = 4096;
            mainSerial.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);
            List<string> usbPorts = ComPortNames("1D50", "6130");
            if (usbPorts.Count > 0)
            {
                sPortsList = new List<string>();
                foreach (string s in SerialPort.GetPortNames())
                {
                    if (usbPorts.Contains(s))
                        sPortsList.Add(s);
                }
            }
        }

        private static void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
        {
            SerialPort sp = (SerialPort)sender;
            string indata = sp.ReadExisting();
            Console.WriteLine("Data Received:");
            Console.Write(indata);
        }

        public void OpenPort()
        {
            mainSerial.PortName = comPortName;
            mainSerial.ReadTimeout = 1000;
            mainSerial.WriteTimeout = 1000;
            try
            {
                mainSerial.Open();
            }
            catch { }
        }

        public void ClosePort()
        {
            try
            {
                mainSerial.Close();
            }
            catch { }
        }

        public bool GetPortOpened()
        {
            return mainSerial.IsOpen;
        }

        public void clearBuffer() {
            mainSerial.DiscardInBuffer();
            mainSerial.DiscardOutBuffer();
        }

        public void SendBytes(byte[] db, int dc)
        {
            try
            {
                mainSerial.Write(db, 0, dc);
            }
            catch { }

            //while (mainSerial.BytesToWrite >= 0) { }
            //mainSerial.DiscardOutBuffer();
        }

        public byte[] WaitForBytes(int dc)
        {
            byte[] result = new byte[dc];

            try
            {
                mainSerial.Read(result, 0, dc);
            }
            catch  { }

            //while (mainSerial.BytesToRead >= 0) { }
            //mainSerial.DiscardOutBuffer();

            return result;
        }

        /// <summary>
        /// Compile an array of COM port names associated with given VID and PID
        /// </summary>
        /// <param name="VID"></param>
        /// <param name="PID"></param>
        /// <returns></returns>
        List<string> ComPortNames(String VID, String PID)
        {
            String pattern = String.Format("^VID_{0}.PID_{1}", VID, PID);
            Regex _rx = new Regex(pattern, RegexOptions.IgnoreCase);
            List<string> comports = new List<string>();
            RegistryKey rk1 = Registry.LocalMachine;
            RegistryKey rk2 = rk1.OpenSubKey("SYSTEM\\CurrentControlSet\\Enum");
            foreach (String s3 in rk2.GetSubKeyNames())
            {
                RegistryKey rk3 = rk2.OpenSubKey(s3);
                foreach (String s in rk3.GetSubKeyNames())
                {
                    if (_rx.Match(s).Success)
                    {
                        RegistryKey rk4 = rk3.OpenSubKey(s);
                        foreach (String s2 in rk4.GetSubKeyNames())
                        {
                            RegistryKey rk5 = rk4.OpenSubKey(s2);
                            RegistryKey rk6 = rk5.OpenSubKey("Device Parameters");
                            comports.Add((string)rk6.GetValue("PortName"));
                        }
                    }
                }
            }
            return comports;
        }
    }
}