using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.ServiceProcess;
using System.Text;
using System.IO;
using System.IO.Ports;
using System.Runtime.InteropServices;

namespace PortMon
{
    public partial class PortMon : ServiceBase
    {
        public static string buf;

        public PortMon()
        {
            InitializeComponent();
            buf = "";
        }

        [DllImport("kernel32")]
        public static extern bool SetConsoleCtrlHandler(HandlerRoutine Handler, bool Add);
        public delegate bool HandlerRoutine(CtrlTypes CtrlType);

        // define the enum for the control event types
        public enum CtrlTypes
        {
            CTRL_C_EVENT = 0,
            CTRL_BREAK_EVENT,
            CTRL_CLOSE_EVENT,
            CTRL_LOGOFF_EVENT=5,
            CTRL_SHUTDOWN_EVENT
        }

        // the handler function for the control event
        private static bool CtrlCheck(CtrlTypes ctrlType)
        {
            if (ctrlType == CtrlTypes.CTRL_LOGOFF_EVENT) return false;
            return true;
        }


        protected string splitStr(string ins)
        {
            // split the incoming string into lines including empty lines
            string[] rows = ins.Split('\n');
            
            // output the lines whereever we need them
            for (int i = 0; i < rows.Length - 1; i++)
            {
                string text = rows[i] + ",date=" + DateTime.Now.ToString()+"\r\n";
                File.AppendAllText("c:\\portlog.txt", text);
            }
            // look for a timeout as well if there is a too long break
            // mark the time for this occasion

            // return the last line fragment
            return rows[rows.Length - 1];
        }

        protected void OnReceive(object sender, SerialDataReceivedEventArgs e)
        {
            SerialPort com = (SerialPort)sender;
            buf += com.ReadExisting();
            buf = splitStr(buf);
        }

        protected override void OnStart(string[] args)
        {
            // do a discovery of portnames
            string[] portnames = SerialPort.GetPortNames();
            foreach (string s in portnames)
            {
                File.AppendAllText("c:\\portlog.txt", "<"+s+">\r\n");
            }

            string port = "COM3";
            if (args.Length >= 1)
            {
                port = args[0];
            }
            myComPort.PortName = port;
            myComPort.Open();

            SetConsoleCtrlHandler(new HandlerRoutine(CtrlCheck), true);


            // write log to file
            string text = "#Service started on port " + port + " at ";
            text += DateTime.Now.ToString() + "\r\n";
            File.AppendAllText("c:\\portlog.txt", text);
        }

        protected override void OnStop()
        {
            // write log to file
            string text = "#Service stopped at " + DateTime.Now.ToString() + "\r\n";
            File.AppendAllText("c:\\portlog.txt", text);
        }
    }
}