/***************************************************************************
 *   Copyright (C) 2010 by David S. Register                               *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, see <https://www.gnu.org/licenses/>. *
 **************************************************************************/

/**
 * \file
 *
 * Implement garmin_protocol_mgr.h -- Garmin NMEA Data Stream Object
 *
 * Parts of this file were adapted from source code found in
 * John F. Waers (jfwaers@csn.net) public domain program MacGPS45
 */

#include <vector>

#include <stdlib.h>
#include <math.h>
#include <time.h>

#ifndef _MSC_VER
#include <arpa/inet.h>
#include <netinet/tcp.h>
#endif

#ifdef _WIN32
#include <winsock2.h>
#include <windows.h>
#include <winioctl.h>
#include <initguid.h>
#include <setupapi.h>
#endif

#include <wx/wxprec.h>
#ifndef WX_PRECOMP
#include <wx/wx.h>
#endif

#include <wx/datetime.h>
#include <wx/event.h>
#include <wx/log.h>
#include <wx/string.h>
#include <wx/tokenzr.h>
#include <wx/utils.h>

#include "model/comm_drv_n0183_serial.h"
#include "model/config_vars.h"
#include "config.h"
#include "model/garmin_wrapper.h"
#include "model/garmin_protocol_mgr.h"
#include "model/nmea_ctx_factory.h"
#include "nmea0183.h"

#ifdef __ANDROID__
#include "androidUTIL.h"
#endif

#if !defined(NAN)
static const long long lNaN = 0xfff8000000000000;
#define NAN (*(double *)&lNaN)
#endif

#define N_DOG_TIMEOUT 5

#ifdef __WXMSW__
// {2C9C45C2-8E7D-4C08-A12D-816BBAE722C0}
DEFINE_GUID(GARMIN_GUID1, 0x2c9c45c2L, 0x8e7d, 0x4c08, 0xa1, 0x2d, 0x81, 0x6b,
            0xba, 0xe7, 0x22, 0xc0);
#endif

//----------------------------------------------------------------------------
// Garmin Device Management
// Handle USB and Serial Port Garmin PVT protocol data interface.
//----------------------------------------------------------------------------

#ifdef __WXMSW__
BOOL IsUserAdmin(VOID)
/*++
 *            Routine Description: This routine returns TRUE if the caller's
 *            process is a member of the Administrators local group. Caller is
 * NOT expected to be impersonating anyone and is expected to be able to open
 * its own process and process token. Arguments: None. Return Value: TRUE -
 * Caller has Administrators local group. FALSE - Caller does not have
 * Administrators local group. --
 */
{
  BOOL b;
  SID_IDENTIFIER_AUTHORITY NtAuthority = SECURITY_NT_AUTHORITY;
  PSID AdministratorsGroup;
  b = AllocateAndInitializeSid(&NtAuthority, 2, SECURITY_BUILTIN_DOMAIN_RID,
                               DOMAIN_ALIAS_RID_ADMINS, 0, 0, 0, 0, 0, 0,
                               &AdministratorsGroup);
  if (b) {
    if (!CheckTokenMembership(NULL, AdministratorsGroup, &b)) {
      b = FALSE;
    }
    FreeSid(AdministratorsGroup);
  }

  return (b);
}

#endif

BEGIN_EVENT_TABLE(GarminProtocolHandler, wxEvtHandler)
EVT_TIMER(TIMER_GARMIN1, GarminProtocolHandler::OnTimerGarmin1)
END_EVENT_TABLE()

GarminProtocolHandler::GarminProtocolHandler(wxString port,
                                             SendMsgFunc send_msg_func,
                                             bool bsel_usb) {
  // m_pparent = parent;
  m_send_msg_func = send_msg_func;
  m_garmin_serial_thread = NULL;
  m_garmin_usb_thread = NULL;
  m_bOK = false;
  m_busb = bsel_usb;

  //      Connect(wxEVT_OCPN_GARMIN,
  //      (wxObjectEventFunction)(wxEventFunction)&GarminProtocolHandler::OnEvtGarmin);

  char pvt_on[14] = {20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 49, 0};

  char pvt_off[14] = {20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 50, 0};

#ifdef __WXMSW__
  if (m_busb) {
    m_usb_handle = INVALID_HANDLE_VALUE;

    m_bneed_int_reset = true;
    m_receive_state = rs_fromintr;
    m_ndelay = 0;

    wxLogMessage("Searching for Garmin DeviceInterface and Device...");

    if (!FindGarminDeviceInterface()) {
      wxLogMessage("   Find:Is the Garmin USB driver installed?");
    } else {
      if (!ResetGarminUSBDriver())
        wxLogMessage("   Reset:Is the Garmin USB Device plugged in?");
    }
  }
#endif

  //  Not using USB, so try a Garmin port open and device ident
  if (!m_busb) {
    m_port = port;

    // Start handler thread
    m_garmin_serial_thread =
        new GARMIN_Serial_Thread(this, m_send_msg_func, m_port);

    m_Thread_run_flag = 1;
    m_garmin_serial_thread->Run();
  }

  TimerGarmin1.SetOwner(this, TIMER_GARMIN1);
  TimerGarmin1.Start(100);
}

GarminProtocolHandler::~GarminProtocolHandler() {}

void GarminProtocolHandler::Close() {
  TimerGarmin1.Stop();

  StopIOThread(true);
  StopSerialThread();
}

void GarminProtocolHandler::StopSerialThread() {
  if (m_garmin_serial_thread) {
    wxLogMessage("Stopping Garmin Serial thread");
    m_Thread_run_flag = 0;

    int tsec = 5;
    while ((m_Thread_run_flag >= 0) && (tsec--)) {
      wxSleep(1);
    }

    wxString msg;
    if (m_Thread_run_flag < 0)
      msg.Printf("Stopped in %d sec.", 5 - tsec);
    else
      msg.Printf("Not Stopped after 5 sec.");
    wxLogMessage(msg);
  }

  m_garmin_serial_thread = NULL;
}

void GarminProtocolHandler::StopIOThread(bool b_pause) {
  if (b_pause) TimerGarmin1.Stop();

  if (m_garmin_usb_thread) {
    wxLogMessage("Stopping Garmin USB thread");
    m_Thread_run_flag = 0;

    int tsec = 5;
    while ((m_Thread_run_flag >= 0) && (tsec--)) {
      wxSleep(1);
    }

    wxString msg;
    if (m_Thread_run_flag < 0)
      msg.Printf("Stopped in %d sec.", 5 - tsec);
    else
      msg.Printf("Not Stopped after 5 sec.");
    wxLogMessage(msg);
  }

  m_garmin_usb_thread = NULL;

#ifdef __WXMSW__
  if (m_busb && (m_usb_handle != INVALID_HANDLE_VALUE))
    CloseHandle(m_usb_handle);
  m_usb_handle = INVALID_HANDLE_VALUE;
#endif

  m_ndelay = 30;  // Fix delay for next restart
}

void GarminProtocolHandler::RestartIOThread() {
  wxLogMessage("Restarting Garmin I/O thread");
  TimerGarmin1.Start(1000);
}

void GarminProtocolHandler::OnTimerGarmin1(wxTimerEvent &event) {
  char pvt_on[14] = {20, 0, 0, 0, 10, 0, 0, 0, 2, 0, 0, 0, 49, 0};

  TimerGarmin1.Stop();

  if (m_busb) {
#ifdef __WXMSW__
    //  Try to open the Garmin USB device
    if (INVALID_HANDLE_VALUE == m_usb_handle) {
      if (INVALID_HANDLE_VALUE != garmin_usb_start()) {
        //    Send out a request for Garmin PVT data
        m_receive_state = rs_fromintr;
        gusb_cmd_send((const garmin_usb_packet *)pvt_on, sizeof(pvt_on));

        //    Start the pump
        m_garmin_usb_thread = new GARMIN_USB_Thread(
            this, m_send_msg_func, (wxIntPtr)m_usb_handle, m_max_tx_size);
        m_Thread_run_flag = 1;
        m_garmin_usb_thread->Run();
      }
    }
#endif
  }

  TimerGarmin1.Start(1000);
}

#ifdef __WXMSW__
bool GarminProtocolHandler::ResetGarminUSBDriver() {
  OSVERSIONINFO version_info;
  version_info.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);

  if (GetVersionEx(&version_info)) {
    if (version_info.dwMajorVersion > 5) {
      if (!IsUserAdmin()) {
        wxLogMessage(
            "    GarminUSBDriver Reset skipped, requires elevated "
            "privileges on Vista and later....");
        return true;
      }
    }
  }

  HDEVINFO devs;
  SP_DEVINFO_DATA devInfo;
  SP_PROPCHANGE_PARAMS pchange;

  devs = SetupDiGetClassDevs((GUID *)&GARMIN_GUID1, NULL, NULL,
                             DIGCF_PRESENT | DIGCF_INTERFACEDEVICE);
  if (devs == INVALID_HANDLE_VALUE) return false;

  devInfo.cbSize = sizeof(devInfo);
  if (!SetupDiEnumDeviceInfo(devs, 0, &devInfo)) {
    wxLogMessage("   GarminUSBDriver Reset0 failed...");
    return false;
  }

  pchange.ClassInstallHeader.cbSize = sizeof(SP_CLASSINSTALL_HEADER);
  pchange.ClassInstallHeader.InstallFunction = DIF_PROPERTYCHANGE;
  pchange.StateChange = DICS_PROPCHANGE;
  pchange.Scope = DICS_FLAG_CONFIGSPECIFIC;
  pchange.HwProfile = 0;

  if (!SetupDiSetClassInstallParams(devs, &devInfo, &pchange.ClassInstallHeader,
                                    sizeof(pchange))) {
    wxLogMessage("   GarminUSBDriver Reset1 failed...");
    return false;
  }

  if (!SetupDiCallClassInstaller(DIF_PROPERTYCHANGE, devs, &devInfo)) {
    wxLogMessage("   GarminUSBDriver Reset2 failed...");
    return false;
  }

  wxLogMessage("GarminUSBDriver Reset succeeded.");

  return true;
}

bool GarminProtocolHandler::
    FindGarminDeviceInterface() {  //    Search for a useable Garmin Device
                                   //    Interface Class

  HDEVINFO hdevinfo;
  SP_DEVINFO_DATA devInfo;

  hdevinfo = SetupDiGetClassDevs((GUID *)&GARMIN_GUID1, NULL, NULL,
                                 DIGCF_PRESENT | DIGCF_INTERFACEDEVICE);

  if (hdevinfo != INVALID_HANDLE_VALUE) {
    devInfo.cbSize = sizeof(devInfo);
    if (!SetupDiEnumDeviceInfo(hdevinfo, 0, &devInfo)) {
      return false;
    }
  }

  return true;
}

bool GarminProtocolHandler::IsGarminPlugged() {
  DWORD size = 0;

  HDEVINFO hdevinfo;
  SP_DEVICE_INTERFACE_DATA infodata;

  //    Search for the Garmin Device Interface Class
  hdevinfo = SetupDiGetClassDevs((GUID *)&GARMIN_GUID1, NULL, NULL,
                                 DIGCF_PRESENT | DIGCF_INTERFACEDEVICE);

  if (hdevinfo == INVALID_HANDLE_VALUE) return INVALID_HANDLE_VALUE;

  infodata.cbSize = sizeof(infodata);

  bool bgarmin_unit_found =
      (SetupDiEnumDeviceInterfaces(hdevinfo, NULL, (GUID *)&GARMIN_GUID1, 0,
                                   &infodata) != 0);

  if (!bgarmin_unit_found) return false;

  PSP_INTERFACE_DEVICE_DETAIL_DATA pdd = NULL;
  SP_DEVINFO_DATA devinfo;

  SetupDiGetDeviceInterfaceDetail(hdevinfo, &infodata, NULL, 0, &size, NULL);

  pdd = (PSP_INTERFACE_DEVICE_DETAIL_DATA)malloc(size);
  pdd->cbSize = sizeof(SP_INTERFACE_DEVICE_DETAIL_DATA);

  devinfo.cbSize = sizeof(SP_DEVINFO_DATA);
  if (!SetupDiGetDeviceInterfaceDetail(hdevinfo, &infodata, pdd, size, NULL,
                                       &devinfo)) {
    free(pdd);
    return false;
  }

  free(pdd);

  return true;
}

HANDLE GarminProtocolHandler::garmin_usb_start() {
  DWORD size = 0;

  HDEVINFO hdevinfo;
  SP_DEVICE_INTERFACE_DATA infodata;

  //    Search for the Garmin Device Interface Class
  hdevinfo = SetupDiGetClassDevs((GUID *)&GARMIN_GUID1, NULL, NULL,
                                 DIGCF_PRESENT | DIGCF_INTERFACEDEVICE);

  if (hdevinfo == INVALID_HANDLE_VALUE) return INVALID_HANDLE_VALUE;

  infodata.cbSize = sizeof(infodata);

  bool bgarmin_unit_found =
      (SetupDiEnumDeviceInterfaces(hdevinfo, NULL, (GUID *)&GARMIN_GUID1, 0,
                                   &infodata) != 0);

  if (!bgarmin_unit_found) return INVALID_HANDLE_VALUE;

  wxLogMessage("Garmin USB Device Found");

  if ((m_usb_handle == INVALID_HANDLE_VALUE) || (m_usb_handle == 0)) {
    PSP_INTERFACE_DEVICE_DETAIL_DATA pdd = NULL;
    SP_DEVINFO_DATA devinfo;

    SetupDiGetDeviceInterfaceDetail(hdevinfo, &infodata, NULL, 0, &size, NULL);

    pdd = (PSP_INTERFACE_DEVICE_DETAIL_DATA)malloc(size);
    pdd->cbSize = sizeof(SP_INTERFACE_DEVICE_DETAIL_DATA);

    devinfo.cbSize = sizeof(SP_DEVINFO_DATA);
    if (!SetupDiGetDeviceInterfaceDetail(hdevinfo, &infodata, pdd, size, NULL,
                                         &devinfo)) {
      wxLogMessage(
          "   SetupDiGetDeviceInterfaceDetail failed for Garmin Device...");
      free(pdd);
      return INVALID_HANDLE_VALUE;
    }

    /* Whew.  All that just to get something we can open... */
    //            wxString msg;
    //            msg.Printf(_T("Windows GUID for interface is
    //            %s"),pdd->DevicePath); wxLogMessage(msg);

    if (m_bneed_int_reset) {
      ResetGarminUSBDriver();
      m_bneed_int_reset = false;
    }

    m_usb_handle = CreateFile(pdd->DevicePath, GENERIC_READ | GENERIC_WRITE, 0,
                              NULL, OPEN_EXISTING, 0, NULL);

    if (m_usb_handle == INVALID_HANDLE_VALUE) {
      wxString msg;
      msg.Printf("   (usb) CreateFile on '%s' failed", pdd->DevicePath);
      wxLogMessage(msg);
    }

    /*
            DEV_BROADCAST_HANDLE filterData;
            filterData.dbch_size = sizeof(DEV_BROADCAST_HANDLE);
            filterData.dbch_devicetype = DBT_DEVTYP_HANDLE;
            filterData.dbch_reserved = 0;
            filterData.dbch_handle = m_usb_handle;     // file handle used in
       call to RegisterDeviceNotification filterData.dbch_hdevnotify = 0; //
       returned from RegisterDeviceNotification

            HDEVNOTIFY m_hDevNotify = RegisterDeviceNotification( GetHWND(),
       &filterData, DEVICE_NOTIFY_WINDOW_HANDLE);
    */

    free(pdd);
  }

  m_max_tx_size = 0;

  if (!DeviceIoControl(m_usb_handle, IOCTL_GARMIN_USB_BULK_OUT_PACKET_SIZE,
                       NULL, 0, &m_max_tx_size, GARMIN_USB_INTERRUPT_DATA_SIZE,
                       &size, NULL)) {
    wxLogMessage("   Couldn't get Garmin USB packet size.");
    CloseHandle(m_usb_handle);
    m_usb_handle = INVALID_HANDLE_VALUE;
    return INVALID_HANDLE_VALUE;
  }

  if (!gusb_syncup()) {
    CloseHandle(m_usb_handle);
    m_usb_handle = INVALID_HANDLE_VALUE;
  }

  return m_usb_handle;
}

bool GarminProtocolHandler::gusb_syncup() {
  static int unit_number;
  static const char oinit[12] = {0, 0, 0, 0, GUSB_SESSION_START, 0, 0, 0,
                                 0, 0, 0, 0};
  garmin_usb_packet iresp;
  int i;

  /*
   * This is our first communication with the unit.
   */

  m_receive_state = rs_fromintr;

  for (i = 0; i < 25; i++) {
    le_write16(&iresp.gusb_pkt.pkt_id[0], 0);
    le_write32(&iresp.gusb_pkt.datasz[0], 0);
    le_write32(&iresp.gusb_pkt.databuf[0], 0);

    if (gusb_cmd_send((const garmin_usb_packet *)oinit, sizeof(oinit))) {
      gusb_cmd_get(&iresp, sizeof(iresp));

      if ((le_read16(iresp.gusb_pkt.pkt_id) == GUSB_SESSION_ACK) &&
          (le_read32(iresp.gusb_pkt.datasz) == 4)) {
        //                unsigned serial_number =
        //                le_read32(iresp.gusb_pkt.databuf);
        //                garmin_unit_info[unit_number].serial_number =
        //                serial_number;
        //                gusb_id_unit(&garmin_unit_info[unit_number]);

        unit_number++;

        wxLogMessage("Successful Garmin USB syncup.");
        return true;
        ;
      }
    }
  }
  wxLogMessage("   Unable to establish Garmin USB syncup.");
  return false;
}

int GarminProtocolHandler::gusb_cmd_send(const garmin_usb_packet *opkt,
                                         size_t sz) {
  unsigned int rv;

  unsigned char *obuf = (unsigned char *)&opkt->dbuf[0];

  rv = gusb_win_send(opkt, sz);

  /*
   * Recursion, when used in a disciplined way, can be our friend.
   *
   * The Garmin protocol requires that packets that are exactly
   * a multiple of the max tx size be followed by a zero length
   * packet.  Do that here so we can see it in debugging traces.
   */

  if (sz && !(sz % m_max_tx_size)) {
    wxLogMessage("win_send_call1");
    gusb_win_send(opkt, 0);
    wxLogMessage("win_send_ret1");
  }

  return (rv);
}

int GarminProtocolHandler::gusb_cmd_get(garmin_usb_packet *ibuf, size_t sz) {
  int rv = 0;
  unsigned char *buf = (unsigned char *)&ibuf->dbuf[0];
  int orig_receive_state;
top:
  orig_receive_state = m_receive_state;
  switch (m_receive_state) {
    case rs_fromintr:
      rv = gusb_win_get(ibuf, sz);
      break;
    case rs_frombulk:
      rv = gusb_win_get_bulk(ibuf, sz);
      break;
  }

  /* Adjust internal state and retry the read */
  if ((rv > 0) && (ibuf->gusb_pkt.pkt_id[0] == GUSB_REQUEST_BULK)) {
    m_receive_state = rs_frombulk;
    goto top;
  }
  /*
   * If we were reading from the bulk pipe and we just got
   * a zero request, adjust our internal state.
   * It's tempting to retry the read here to hide this "stray"
   * packet from our callers, but that only works when you know
   * there's another packet coming.   That works in every case
   * except the A000 discovery sequence.
   */
  if ((m_receive_state == rs_frombulk) && (rv <= 0)) {
    m_receive_state = rs_fromintr;
  }

  return rv;
}

int GarminProtocolHandler::gusb_win_get(garmin_usb_packet *ibuf, size_t sz) {
  DWORD rxed = GARMIN_USB_INTERRUPT_DATA_SIZE;
  unsigned char *buf = (unsigned char *)&ibuf->dbuf[0];
  int tsz = 0;

  while (sz) {
    /* The driver wrongly (IMO) rejects reads smaller than
     * GARMIN_USB_INTERRUPT_DATA_SIZE
     */
    if (!DeviceIoControl(m_usb_handle, IOCTL_GARMIN_USB_INTERRUPT_IN, NULL, 0,
                         buf, GARMIN_USB_INTERRUPT_DATA_SIZE, &rxed, NULL)) {
      //                GPS_Serial_Error("Ioctl");
      //                fatal("ioctl\n");
    }

    buf += rxed;
    sz -= rxed;
    tsz += rxed;
    if (rxed < GARMIN_USB_INTERRUPT_DATA_SIZE) break;
  }
  return tsz;
}

int GarminProtocolHandler::gusb_win_get_bulk(garmin_usb_packet *ibuf,
                                             size_t sz) {
  int n;
  DWORD rsz;
  unsigned char *buf = (unsigned char *)&ibuf->dbuf[0];

  n = ReadFile(m_usb_handle, buf, sz, &rsz, NULL);

  return rsz;
}

int GarminProtocolHandler::gusb_win_send(const garmin_usb_packet *opkt,
                                         size_t sz) {
  DWORD rsz;
  unsigned char *obuf = (unsigned char *)&opkt->dbuf[0];

  /* The spec warns us about making writes an exact multiple
   * of the packet size, but isn't clear whether we can issue
   * data in a single call to WriteFile if it spans buffers.
   */
  WriteFile(m_usb_handle, obuf, sz, &rsz, NULL);
  int err = GetLastError();

  //    if (rsz != sz)
  //          fatal ("Error sending %d bytes.   Successfully sent %ld\n", sz,
  //          rsz);

  return rsz;
}

/*
WXLRESULT GarminProtocolHandler::MSWWindowProc(WXUINT message, WXWPARAM wParam,
WXLPARAM lParam)
{
    // did we process the message?
    bool processed = false;

    // the return value
    bool rc;
    PDEV_BROADCAST_HDR pDBHdr;
    PDEV_BROADCAST_HANDLE pDBHandle;

    // for most messages we should return 0 when we do process the message
    rc = 0;

    switch ( message )
    {
        case WM_DEVICECHANGE:
            switch (wParam)
            {
                case DBT_DEVICEREMOVEPENDING:
                case DBT_DEVICEREMOVECOMPLETE:
                    pDBHdr = (PDEV_BROADCAST_HDR) lParam;
                    switch (pDBHdr->dbch_devicetype)
                        case DBT_DEVTYP_HANDLE:
                            // A Device has been removed
                            // Stop the IO thread and close open handle  to
device

                            pDBHandle = (PDEV_BROADCAST_HANDLE) pDBHdr;
                            HANDLE target_handle = pDBHandle->dbch_handle;

                            wxLogMessage("Garmin USB Device Removed");
                            StopIOThread(false);
                            m_bneed_int_reset = true;
                            processed = true;
                            break;
            }

            break;

    }

    if ( !processed )
    {
        rc = (MSWDefWindowProc(message, wParam, lParam) != 0);
    }

    return rc;
}
*/
#endif

D800_Pvt_Data_Type_Aligned mypvt;

//-------------------------------------------------------------------------------------------------------------
//
//    Garmin Serial Port Worker Thread
//
//    This thread manages reading the positioning data stream from the declared
//    Garmin GRMN Mode serial device
//
//-------------------------------------------------------------------------------------------------------------
GARMIN_Serial_Thread::GARMIN_Serial_Thread(GarminProtocolHandler *parent,
                                           SendMsgFunc send_msg_func,
                                           wxString port) {
  m_parent = parent;  // This thread's immediate "parent"
  m_send_msg_func = send_msg_func;
  m_port = port;

  Create();
}

GARMIN_Serial_Thread::~GARMIN_Serial_Thread() {}

//    Entry Point
void *GARMIN_Serial_Thread::Entry() {
  //   m_parent->SetSecThreadActive();               // I am alive
  m_bdetected = false;
  m_bconnected = false;

  bool not_done = true;
  wxDateTime last_rx_time;

#ifdef USE_GARMINHOST
  //    The main loop

  while ((not_done) && (m_parent->m_Thread_run_flag > 0)) {
    if (TestDestroy()) {
      not_done = false;  // smooth exit
      goto thread_exit_2;
    }

    while (!m_bdetected) {
      //  Try to init the port once
      int v_init = Garmin_GPS_Init(m_port);
      if (v_init < 0) {  //  Open failed, so sleep and try again
        for (int i = 0; i < 4; i++) {
          wxSleep(1);
          if (TestDestroy()) goto thread_exit;
          if (!m_parent->m_Thread_run_flag) goto thread_exit;
        }
      } else
        m_bdetected = true;
    }  // while not detected

    // Detected OK

    //      Start PVT packet transmission
    if (!m_bconnected) {
      if (!Garmin_GPS_PVT_On(m_port)) {
        m_bdetected = false;  // error, would not accept PVT On
        m_bconnected = false;
      } else
        m_bconnected = true;
    }

    if (m_bconnected) {
      D800_Pvt_Data_Type_Aligned *ppvt = &mypvt;
      int ret = Garmin_GPS_GetPVT(&ppvt);
      if (ret > 0) {
        if ((mypvt.fix) >= 2 && (mypvt.fix <= 5)) {
          // Synthesize an NMEA GMRMC message
          SENTENCE snt;
          NMEA0183 oNMEA0183(NmeaCtxFactory());
          oNMEA0183.TalkerID = "GM";

          if (mypvt.lat < 0.)
            oNMEA0183.Rmc.Position.Latitude.Set(-mypvt.lat, "S");
          else
            oNMEA0183.Rmc.Position.Latitude.Set(mypvt.lat, "N");

          if (mypvt.lon < 0.)
            oNMEA0183.Rmc.Position.Longitude.Set(-mypvt.lon, "W");
          else
            oNMEA0183.Rmc.Position.Longitude.Set(mypvt.lon, "E");

          /* speed over ground */
          double sog =
              sqrt(mypvt.east * mypvt.east + mypvt.north * mypvt.north) * 3.6 /
              1.852;
          oNMEA0183.Rmc.SpeedOverGroundKnots = sog;

          /* course over ground */
          double course = atan2(mypvt.east, mypvt.north);
          if (course < 0) course += 2 * PI;
          double cog = course * 180 / PI;
          oNMEA0183.Rmc.TrackMadeGoodDegreesTrue = cog;

          oNMEA0183.Rmc.IsDataValid = NTrue;

          oNMEA0183.Rmc.Write(snt);

          // Send message...
          auto msg = snt.Sentence.ToStdString();
          m_send_msg_func(std::vector<unsigned char>(msg.begin(), msg.end()));

          last_rx_time = wxDateTime::Now();
        }
      } else {
        wxDateTime now = wxDateTime::Now();
        if (last_rx_time.IsValid()) {
          wxTimeSpan delta_time = now - last_rx_time;
          if (delta_time.GetSeconds() > 5) {
            m_bdetected = false;
            m_bconnected = false;
            Garmin_GPS_ClosePortVerify();
          }
        }
      }
    }
  }  // the big while...

thread_exit_2:

  Garmin_GPS_PVT_Off(m_port);
  Garmin_GPS_ClosePortVerify();

  while ((not_done) && (m_parent->m_Thread_run_flag > 0)) {
    wxSleep(1);
    if (TestDestroy()) {
      not_done = false;  // smooth exit
      goto thread_exit;
    }
  }

thread_exit:

#endif  // #ifdef USE_GARMINHOST

  m_parent->m_Thread_run_flag = -1;  // in GarminProtocolHandler
  return 0;
}

//-------------------------------------------------------------------------------------------------------------
//    GARMIN_USB_Thread Implementation
//-------------------------------------------------------------------------------------------------------------
#if 1
GARMIN_USB_Thread::GARMIN_USB_Thread(GarminProtocolHandler *parent,
                                     SendMsgFunc send_msg_func,
                                     unsigned int device_handle,
                                     size_t max_tx_size) {
  m_parent = parent;  // This thread's immediate "parent"
  m_send_msg_func = send_msg_func;
  m_max_tx_size = max_tx_size;

#ifdef __WXMSW__
  m_usb_handle = (HANDLE)(device_handle & 0xffff);
#endif

  Create();
}

GARMIN_USB_Thread::~GARMIN_USB_Thread() {}

void *GARMIN_USB_Thread::Entry() {
  garmin_usb_packet iresp = {{0}};
  int n_short_read = 0;
  m_receive_state = rs_fromintr;

  //    Here comes the big while loop
  while (m_parent->m_Thread_run_flag > 0) {
    if (TestDestroy()) goto thread_prexit;  // smooth exit

    //    Get one  packet

    int nr = gusb_cmd_get(&iresp, sizeof(iresp));

    if (iresp.gusb_pkt.pkt_id[0] == GUSB_RESPONSE_SDR)  // Satellite Data Record
    {
      unsigned char *t = (unsigned char *)&(iresp.gusb_pkt.databuf[0]);
      for (int i = 0; i < 12; i++) {
        m_sat_data[i].svid = *t++;
        m_sat_data[i].snr = ((*t) << 8) + *(t + 1);
        t += 2;
        m_sat_data[i].elev = *t++;
        m_sat_data[i].azmth = ((*t) << 8) + *(t + 1);
        t += 2;
        m_sat_data[i].status = *t++;
      }

      m_nSats = 0;
      for (int i = 0; i < 12; i++) {
        if (m_sat_data[i].svid != 255) m_nSats++;
      }

      // Synthesize an NMEA GMGSV message
      SENTENCE snt;
      NMEA0183 oNMEA0183(NmeaCtxFactory());
      oNMEA0183.TalkerID = "GM";
      oNMEA0183.Gsv.SatsInView = m_nSats;

      oNMEA0183.Gsv.Write(snt);
      wxString msg = snt.Sentence;

      // and send message.
      m_send_msg_func(std::vector<unsigned char>(msg.begin(), msg.end()));
    }

    if (iresp.gusb_pkt.pkt_id[0] == GUSB_RESPONSE_PVT)  // PVT Data Record
    {
      D800_Pvt_Data_Type *ppvt =
          (D800_Pvt_Data_Type *)&(iresp.gusb_pkt.databuf[0]);

      if ((ppvt->fix) >= 2 && (ppvt->fix <= 5)) {
        // Synthesize an NMEA GMRMC message
        SENTENCE snt;
        NMEA0183 oNMEA0183(NmeaCtxFactory());
        oNMEA0183.TalkerID = "GM";

        if (ppvt->lat < 0.)
          oNMEA0183.Rmc.Position.Latitude.Set(-ppvt->lat * 180. / PI, "S");
        else
          oNMEA0183.Rmc.Position.Latitude.Set(ppvt->lat * 180. / PI, "N");

        if (ppvt->lon < 0.)
          oNMEA0183.Rmc.Position.Longitude.Set(-ppvt->lon * 180. / PI, "W");
        else
          oNMEA0183.Rmc.Position.Longitude.Set(ppvt->lon * 180. / PI, "E");

        /* speed over ground */
        double sog = sqrt(ppvt->east * ppvt->east + ppvt->north * ppvt->north) *
                     3.6 / 1.852;
        oNMEA0183.Rmc.SpeedOverGroundKnots = sog;

        /* course over ground */
        double course = atan2(ppvt->east, ppvt->north);
        if (course < 0) course += 2 * PI;
        double cog = course * 180 / PI;
        oNMEA0183.Rmc.TrackMadeGoodDegreesTrue = cog;

        oNMEA0183.Rmc.IsDataValid = NTrue;

        oNMEA0183.Rmc.Write(snt);
        wxString msg = snt.Sentence;
        m_send_msg_func(std::vector<unsigned char>(msg.begin(), msg.end()));
      }
    }
  }
thread_prexit:
  m_parent->m_Thread_run_flag = -1;
  return 0;
}

int GARMIN_USB_Thread::gusb_cmd_get(garmin_usb_packet *ibuf, size_t sz) {
  int rv = 0;
  unsigned char *buf = (unsigned char *)&ibuf->dbuf[0];
  int orig_receive_state;
top:
  orig_receive_state = m_receive_state;
  switch (m_receive_state) {
    case rs_fromintr:
      rv = gusb_win_get(ibuf, sz);
      break;
    case rs_frombulk:
      rv = gusb_win_get_bulk(ibuf, sz);
      break;
  }

  /* Adjust internal state and retry the read */
  if ((rv > 0) && (ibuf->gusb_pkt.pkt_id[0] == GUSB_REQUEST_BULK)) {
    m_receive_state = rs_frombulk;
    goto top;
  }
  /*
   * If we were reading from the bulk pipe and we just got
   * a zero request, adjust our internal state.
   * It's tempting to retry the read here to hide this "stray"
   * packet from our callers, but that only works when you know
   * there's another packet coming.   That works in every case
   * except the A000 discovery sequence.
   */
  if ((m_receive_state == rs_frombulk) && (rv <= 0)) {
    m_receive_state = rs_fromintr;
  }

  return rv;
}

int GARMIN_USB_Thread::gusb_win_get(garmin_usb_packet *ibuf, size_t sz) {
  int tsz = 0;
#ifdef __WXMSW__
  DWORD rxed = GARMIN_USB_INTERRUPT_DATA_SIZE;
  unsigned char *buf = (unsigned char *)&ibuf->dbuf[0];

  while (sz) {
    /* The driver wrongly (IMO) rejects reads smaller than
     * GARMIN_USB_INTERRUPT_DATA_SIZE
     */
    if (!DeviceIoControl(m_usb_handle, IOCTL_GARMIN_USB_INTERRUPT_IN, NULL, 0,
                         buf, GARMIN_USB_INTERRUPT_DATA_SIZE, &rxed, NULL)) {
      //                GPS_Serial_Error("Ioctl");
      //                fatal("ioctl\n");
    }

    buf += rxed;
    sz -= rxed;
    tsz += rxed;
    if (rxed < GARMIN_USB_INTERRUPT_DATA_SIZE) break;
  }

#endif
  return tsz;
}

int GARMIN_USB_Thread::gusb_win_get_bulk(garmin_usb_packet *ibuf, size_t sz) {
  int n;
  int ret_val = 0;
#ifdef __WXMSW__
  DWORD rsz;
  unsigned char *buf = (unsigned char *)&ibuf->dbuf[0];

  n = ReadFile(m_usb_handle, buf, sz, &rsz, NULL);
  ret_val = rsz;
#endif

  return ret_val;
}
#endif
