/*

   This Source Code Form is subject to the terms of the Mozilla Public

   License, v. 2.0. If a copy of the MPL was not distributed with this

   file, You can obtain one at http://mozilla.org/MPL/2.0/.

   Copyright (C) 2010 Michael Möller <mmoeller@openhardwaremonitor.org>

 */

 using System;

 using System.Collections.Generic;

 using System.Globalization;

 using System.IO.Ports;

 using System.Security;

 using System.Text;

 using System.Threading;

 using Microsoft.Win32;

 namespace OpenHardwareMonitor.Hardware.Heatmaster {

   internal class HeatmasterGroup : IGroup {

     private readonly List<Heatmaster> hardware = new List<Heatmaster>();

     private readonly StringBuilder report = new StringBuilder();

     private static string ReadLine(SerialPort port, int timeout) {

       int i = 0;

       StringBuilder builder = new StringBuilder();

       while (i < timeout) {

         while (port.BytesToRead > 0) {

           byte b = (byte)port.ReadByte();

           switch (b) {

             case 0xAA: return ((char)b).ToString();

             case 0x0D: return builder.ToString();

             default: builder.Append((char)b); break;

           }

         }

         i++;

         Thread.Sleep(1);

       }

       throw new TimeoutException();

     }

     private static string[] GetRegistryPortNames() {

       List<string> result = new List<string>();

       string[] paths = { "", "&MI_00" };

       try {

         foreach (string path in paths) {

           RegistryKey key = Registry.LocalMachine.OpenSubKey(

             @"SYSTEM\CurrentControlSet\Enum\USB\VID_10C4&PID_EA60" + path);

           if (key != null) {

             foreach (string subKeyName in key.GetSubKeyNames()) {

               RegistryKey subKey =

                 key.OpenSubKey(subKeyName + "\\" + "Device Parameters");

               if (subKey != null) {

                 string name = subKey.GetValue("PortName") as string;

                 if (name != null && !result.Contains(name))

                   result.Add(name);

               }

             }

           }

         }

       } catch (SecurityException) { }

       return result.ToArray();

     }

     public HeatmasterGroup(ISettings settings) {

       // No implementation for Heatmaster on Unix systems

       int p = (int)Environment.OSVersion.Platform;

       if ((p == 4) || (p == 128))

         return;

       string[] portNames = GetRegistryPortNames();      

       for (int i = 0; i < portNames.Length; i++) {

         bool isValid = false;

         try {        

           using (SerialPort serialPort =

             new SerialPort(portNames[i], 38400, Parity.None, 8, StopBits.One)) {

             serialPort.NewLine = ((char)0x0D).ToString();            

             report.Append("Port Name: "); report.AppendLine(portNames[i]);

             try {

               serialPort.Open();

             } catch (UnauthorizedAccessException) {

               report.AppendLine("Exception: Access Denied");

             }

             if (serialPort.IsOpen) {

               serialPort.DiscardInBuffer();

               serialPort.DiscardOutBuffer();

               serialPort.Write(new byte[] { 0xAA }, 0, 1);

               int j = 0;

               while (serialPort.BytesToRead == 0 && j < 10) {

                 Thread.Sleep(20);

                 j++;

               }

               if (serialPort.BytesToRead > 0) {

                 bool flag = false;

                 while (serialPort.BytesToRead > 0 && !flag) {

                   flag |= (serialPort.ReadByte() == 0xAA);

                 }

                 if (flag) {

                   serialPort.WriteLine("[0:0]RH");

                   try {

                     int k = 0;

                     int revision = 0;

                     while (k < 5) {

                       string line = ReadLine(serialPort, 100);

                       if (line.StartsWith("-[0:0]RH:",

                         StringComparison.Ordinal)) {

                         revision = int.Parse(line.Substring(9), 

                           CultureInfo.InvariantCulture);

                         break;

                       }

                       k++;

                     }

                     isValid = (revision == 770);

                     if (!isValid) {

                       report.Append("Status: Wrong Hardware Revision " +

                         revision.ToString(CultureInfo.InvariantCulture));

                     }

                   } catch (TimeoutException) {

                     report.AppendLine("Status: Timeout Reading Revision");

                   }

                 } else {

                   report.AppendLine("Status: Wrong Startflag");

                 }

               } else {

                 report.AppendLine("Status: No Response");

               }

               serialPort.DiscardInBuffer();

             } else {

               report.AppendLine("Status: Port not Open");

             }            

           }

         } catch (Exception e) {

           report.AppendLine(e.ToString());

         }

         if (isValid) {

           report.AppendLine("Status: OK");

           hardware.Add(new Heatmaster(portNames[i], settings));

         }

         report.AppendLine();

       }

     }

     public IHardware[] Hardware {

       get {

         return hardware.ToArray();

       }

     }

     public string GetReport() {

       if (report.Length > 0) {

         StringBuilder r = new StringBuilder();

         r.AppendLine("Serial Port Heatmaster");

         r.AppendLine();

         r.Append(report);

         r.AppendLine();

         return r.ToString();

       } else

         return null;

     }

     public void Close() {

       foreach (Heatmaster heatmaster in hardware)

         heatmaster.Close();

     }

   }

 }