/*

  Version: MPL 1.1/GPL 2.0/LGPL 2.1

  The contents of this file are subject to the Mozilla Public License Version

  1.1 (the "License"); you may not use this file except in compliance with

  the License. You may obtain a copy of the License at

  http://www.mozilla.org/MPL/

  Software distributed under the License is distributed on an "AS IS" basis,

  WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License

  for the specific language governing rights and limitations under the License.

  The Original Code is the Open Hardware Monitor code.

  The Initial Developer of the Original Code is 

  Michael Möller <m.moeller@gmx.ch>.

  Portions created by the Initial Developer are Copyright (C) 2009-2010

  the Initial Developer. All Rights Reserved.

  Contributor(s):

  Alternatively, the contents of this file may be used under the terms of

  either the GNU General Public License Version 2 or later (the "GPL"), or

  the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),

  in which case the provisions of the GPL or the LGPL are applicable instead

  of those above. If you wish to allow use of your version of this file only

  under the terms of either the GPL or the LGPL, and not to allow others to

  use your version of this file under the terms of the MPL, indicate your

  decision by deleting the provisions above and replace them with the notice

  and other provisions required by the GPL or the LGPL. If you do not delete

  the provisions above, a recipient may use your version of this file under

  the terms of any one of the MPL, the GPL or the LGPL.

*/

using System;

using System.Runtime.InteropServices;

namespace OpenHardwareMonitor.Hardware.TBalancer {

  internal enum FT_DEVICE : uint {

    FT_DEVICE_232BM,

    FT_DEVICE_232AM,

    FT_DEVICE_100AX,

    FT_DEVICE_UNKNOWN,

    FT_DEVICE_2232C,

    FT_DEVICE_232R,

    FT_DEVICE_2232H,

    FT_DEVICE_4232H

  }

  internal enum FT_STATUS {

    FT_OK,

    FT_INVALID_HANDLE,

    FT_DEVICE_NOT_FOUND,

    FT_DEVICE_NOT_OPENED,

    FT_IO_ERROR,

    FT_INSUFFICIENT_RESOURCES,

    FT_INVALID_PARAMETER,

    FT_INVALID_BAUD_RATE,

    FT_DEVICE_NOT_OPENED_FOR_ERASE,

    FT_DEVICE_NOT_OPENED_FOR_WRITE,

    FT_FAILED_TO_WRITE_DEVICE,

    FT_EEPROM_READ_FAILED,

    FT_EEPROM_WRITE_FAILED,

    FT_EEPROM_ERASE_FAILED,

    FT_EEPROM_NOT_PRESENT,

    FT_EEPROM_NOT_PROGRAMMED,

    FT_INVALID_ARGS,

    FT_OTHER_ERROR

  }

  internal enum FT_FLOW_CONTROL : ushort {

    FT_FLOW_DTR_DSR = 512,

    FT_FLOW_NONE = 0,

    FT_FLOW_RTS_CTS = 256,

    FT_FLOW_XON_XOFF = 1024,

  }

  internal enum FT_PURGE : uint {

    FT_PURGE_RX = 1,

    FT_PURGE_TX = 2,

    FT_PURGE_ALL = 3,

  }

  [StructLayout(LayoutKind.Sequential)]

  internal struct FT_HANDLE {

    private readonly uint handle;

  }

  [StructLayout(LayoutKind.Sequential)]

  internal struct FT_DEVICE_INFO_NODE {    

    public uint Flags;

    public FT_DEVICE Type; 

    public uint ID; 

    public uint LocId; 

    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 16)]

    public string SerialNumber; 

    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 64)]

    public string Description;

    public FT_HANDLE Handle;

  }

  internal class FTD2XX {

    public delegate FT_STATUS FT_CreateDeviceInfoListDelegate(

      out uint numDevices);

    public delegate FT_STATUS FT_GetDeviceInfoListDelegate(

      [Out] FT_DEVICE_INFO_NODE[] deviceInfoNodes, ref uint length);

    public delegate FT_STATUS FT_OpenDelegate(int device, out FT_HANDLE handle);

    public delegate FT_STATUS FT_CloseDelegate(FT_HANDLE handle);

    public delegate FT_STATUS FT_SetBaudRateDelegate(FT_HANDLE handle,

      uint baudRate);

    public delegate FT_STATUS FT_SetDataCharacteristicsDelegate(

      FT_HANDLE handle, byte wordLength, byte stopBits, byte parity);

    public delegate FT_STATUS FT_SetFlowControlDelegate(FT_HANDLE handle,

      FT_FLOW_CONTROL flowControl, byte xon, byte xoff);

    public delegate FT_STATUS FT_SetTimeoutsDelegate(FT_HANDLE handle,

      uint readTimeout, uint writeTimeout);

    public delegate FT_STATUS FT_WriteDelegate(FT_HANDLE handle, byte[] buffer,

      uint bytesToWrite, out uint bytesWritten);

    public delegate FT_STATUS FT_PurgeDelegate(FT_HANDLE handle, FT_PURGE mask);

    public delegate FT_STATUS FT_GetStatusDelegate(FT_HANDLE handle,

      out uint amountInRxQueue, out uint amountInTxQueue, out uint eventStatus);

    public delegate FT_STATUS FT_ReadDelegate(FT_HANDLE handle, 

      [Out] byte[] buffer, uint bytesToRead, out uint bytesReturned);

    public static readonly FT_CreateDeviceInfoListDelegate 

      FT_CreateDeviceInfoList = CreateDelegate<

      FT_CreateDeviceInfoListDelegate>("FT_CreateDeviceInfoList");

    public static readonly FT_GetDeviceInfoListDelegate 

      FT_GetDeviceInfoList = CreateDelegate<

      FT_GetDeviceInfoListDelegate>("FT_GetDeviceInfoList");

    public static readonly FT_OpenDelegate 

      FT_Open = CreateDelegate<

      FT_OpenDelegate>("FT_Open");

    public static readonly FT_CloseDelegate 

      FT_Close = CreateDelegate<

      FT_CloseDelegate>("FT_Close");

    public static readonly FT_SetBaudRateDelegate 

      FT_SetBaudRate = CreateDelegate<

      FT_SetBaudRateDelegate>("FT_SetBaudRate");

    public static readonly FT_SetDataCharacteristicsDelegate 

      FT_SetDataCharacteristics = CreateDelegate<

      FT_SetDataCharacteristicsDelegate>("FT_SetDataCharacteristics");

    public static readonly FT_SetFlowControlDelegate 

      FT_SetFlowControl = CreateDelegate<

      FT_SetFlowControlDelegate>("FT_SetFlowControl");

    public static readonly FT_SetTimeoutsDelegate 

      FT_SetTimeouts = CreateDelegate<

      FT_SetTimeoutsDelegate>("FT_SetTimeouts");

    public static readonly FT_WriteDelegate 

      FT_Write = CreateDelegate<

      FT_WriteDelegate>("FT_Write");

    public static readonly FT_PurgeDelegate 

      FT_Purge = CreateDelegate<

      FT_PurgeDelegate>("FT_Purge");

    public static readonly FT_GetStatusDelegate 

      FT_GetStatus = CreateDelegate<

      FT_GetStatusDelegate>("FT_GetStatus");

    public static readonly FT_ReadDelegate 

      FT_Read = CreateDelegate<

      FT_ReadDelegate>("FT_Read");

    private FTD2XX() { }

    public static FT_STATUS Write(FT_HANDLE handle, byte[] buffer) {

      uint bytesWritten;

      FT_STATUS status = FT_Write(handle, buffer, (uint)buffer.Length, 

        out bytesWritten);

      if (bytesWritten != buffer.Length)

        return FT_STATUS.FT_FAILED_TO_WRITE_DEVICE;

      else

        return status;

    }

    public static int BytesToRead(FT_HANDLE handle) {

      uint amountInRxQueue;

      uint amountInTxQueue;

      uint eventStatus;

      if (FT_GetStatus(handle, out amountInRxQueue, out amountInTxQueue,

        out eventStatus) == FT_STATUS.FT_OK) {

        return (int)amountInRxQueue;

      } else {

        return 0;

      }

    }

    public static byte ReadByte(FT_HANDLE handle) {

      byte[] buffer = new byte[1];

      uint bytesReturned;

      FT_STATUS status = FT_Read(handle, buffer, 1, out bytesReturned);

      if (status != FT_STATUS.FT_OK || bytesReturned != 1)

        throw new InvalidOperationException();

      return buffer[0];

    }

    private static string GetDllName() {

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

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

        return "libftd2xx.so";

      else

        return "ftd2xx.dll";

    }

    private static T CreateDelegate<T>(string entryPoint)

      where T : class {

      DllImportAttribute attribute = new DllImportAttribute(GetDllName());

      attribute.CallingConvention = CallingConvention.StdCall;

      attribute.PreserveSig = true;

      attribute.EntryPoint = entryPoint;

      T newDelegate;

      PInvokeDelegateFactory.CreateDelegate(attribute, out newDelegate);

      return newDelegate;

    }

  }

}