/***************************************************************************
 *   Copyright (C) 2003 by Martin Koller                                   *
 *   m.koller@surfeu.at                                                    *
 *   This file is part of the KDE Control Center Module for Joysticks      *
 *                                                                         *
 *   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, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#include "joydevice.h"

#include <klocale.h>
#include <kdebug.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/select.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <errno.h>
#include <math.h>

//--------------------------------------------------------------

JoyDevice::JoyDevice(const QString &devicefile)
  : devName(devicefile), joyFd(-1), buttons(0), axes(0),
    amin(0), amax(0), corr(0), origCorr(0)
{
}

//--------------------------------------------------------------

QString JoyDevice::errText(ErrorCode code) const
{
  switch ( code )
  {
    case SUCCESS: return "";

    case OPEN_FAILED:
    {
      return i18n("The given device %1 could not be opened: %2")
                 .arg(devName).arg(strerror(errno));
    }

    case NO_JOYSTICK:
    {
      return i18n("The given device %1 is not a joystick.").arg(devName);
    }

    case ERR_GET_VERSION:
    {
      return i18n("Could not get kernel driver version for joystick device %1: %2")
                 .arg(devName).arg(strerror(errno));
    }

    case WRONG_VERSION:
    {
      int version = 0;
      int fd = ::open(devName.latin1(), O_RDONLY);
      if ( fd != -1 )
      {
        ::ioctl(fd, JSIOCGVERSION, &version);
        ::close(fd);
      }

      return i18n("The current running kernel driver version (%1.%2.%3) is not the one this module was compiled for (%4.%5.%6).")
                 .arg(version    >> 16).arg((version    >> 8) & 0xFF).arg(version    & 0xFF)
                 .arg(JS_VERSION >> 16).arg((JS_VERSION >> 8) & 0xFF).arg(JS_VERSION & 0xFF);
    }

    case ERR_GET_BUTTONS:
    {
      return i18n("Could not get number of buttons for joystick device %1: %2")
                 .arg(devName).arg(strerror(errno));
    }

    case ERR_GET_AXES:
    {
      return i18n("Could not get number of axes for joystick device %1: %2")
                 .arg(devName).arg(strerror(errno));
    }

    case ERR_GET_CORR:
    {
      return i18n("Could not get calibration values for joystick device %1: %2")
                 .arg(devName).arg(strerror(errno));
    }

    case ERR_RESTORE_CORR:
    {
      return i18n("Could not restore calibration values for joystick device %1: %2")
                 .arg(devName).arg(strerror(errno));
    }

    case ERR_INIT_CAL:
    {
      return i18n("Could not initialize calibration values for joystick device %1: %2")
                 .arg(devName).arg(strerror(errno));
    }

    case ERR_APPLY_CAL:
    {
      return i18n("Could not apply calibration values for joystick device %1: %2")
                 .arg(devName).arg(strerror(errno));
    }

    default: return i18n("internal error - code %1 unknown").arg(int(code));
  }
}

//--------------------------------------------------------------

JoyDevice::ErrorCode JoyDevice::open()
{
  if ( joyFd != -1 ) return JoyDevice::SUCCESS;  // already open

  int fd = ::open(devName.latin1(), O_RDONLY);

  if ( fd == -1 )
    return JoyDevice::OPEN_FAILED;

  // we could open the devicefile, now check if a joystick is attached
  char name[128];

  if ( ::ioctl(fd, JSIOCGNAME(sizeof(name)), &name) == -1 )
  {
    ::close(fd);
    return JoyDevice::NO_JOYSTICK;
  }

  // check the kernel driver version
  int version;
  if ( ::ioctl(fd, JSIOCGVERSION, &version) == -1 )
  {
    ::close(fd);
    return JoyDevice::ERR_GET_VERSION;
  }

  if ( version != JS_VERSION )
  {
    ::close(fd);
    return JoyDevice::WRONG_VERSION;
  }

  char bt = 0, ax = 0;
  if ( ::ioctl(fd, JSIOCGBUTTONS, &bt) == -1 )
  {
    ::close(fd);
    return JoyDevice::ERR_GET_BUTTONS;
  }

  if ( ::ioctl(fd, JSIOCGAXES, &ax) == -1 )
  {
    ::close(fd);
    return JoyDevice::ERR_GET_AXES;
  }

  struct js_corr *oldCorr = new struct js_corr[ax];

  if ( ::ioctl(fd, JSIOCGCORR, oldCorr) == -1 )
  {
    ::close(fd);
    delete [] oldCorr;
    return JoyDevice::ERR_GET_CORR;
  }

  descr = name;
  joyFd = fd;
  axes = ax;
  buttons = bt;
  origCorr = oldCorr;
  corr = new struct js_corr[axes];

  amin = new int[axes];
  amax = new int[axes];

  int i;

  for (i = 0; i < axes; i++)
    resetMinMax(i);

  return JoyDevice::SUCCESS;
}

//--------------------------------------------------------------

void JoyDevice::close()
{
  if ( joyFd == -1 ) return;

  ::close(joyFd);

  joyFd = -1;
  descr = "";

  delete [] amin;
  delete [] amax;
  amin = 0;
  amax = 0;

  delete [] corr;
  corr = 0;
  delete [] origCorr;
  origCorr = 0;
}

//--------------------------------------------------------------

int JoyDevice::axisMin(int axis) const
{
  if ( (axis < 0) || (axis >= axes) ) return 0;

  return amin[axis];
}

//--------------------------------------------------------------

int JoyDevice::axisMax(int axis) const
{
  if ( (axis < 0) || (axis >= axes) ) return 0;

  return amax[axis];
}

//--------------------------------------------------------------

JoyDevice::ErrorCode JoyDevice::initCalibration()
{
  if ( joyFd == -1 ) return JoyDevice::ERR_INIT_CAL;

  int i;

  // Reset all current correction values
  for (i = 0; i < axes; i++)
  {
    corr[i].type = JS_CORR_NONE;
    corr[i].prec = 0;
  }

  if ( ::ioctl(joyFd, JSIOCSCORR, corr) == -1 )
    return JoyDevice::ERR_INIT_CAL;

  for (i = 0; i < axes; i++)
    corr[i].type = JS_CORR_BROKEN;

  return JoyDevice::SUCCESS;
}

//--------------------------------------------------------------

JoyDevice::ErrorCode JoyDevice::applyCalibration()
{
  if ( joyFd == -1 ) return JoyDevice::ERR_APPLY_CAL;

  if ( ::ioctl(joyFd, JSIOCSCORR, corr) == -1 )
    return JoyDevice::ERR_APPLY_CAL;

  return JoyDevice::SUCCESS;
}

//--------------------------------------------------------------

void JoyDevice::resetMinMax(int axis, int value)
{
  amin[axis] = value;
  amax[axis] = value;
}

//--------------------------------------------------------------

void JoyDevice::calcPrecision()
{
  if ( !corr ) return;

  int i;

  for (i = 0; i < axes; i++)
  {
    corr[i].prec = amax[i] - amin[i];
    kdDebug() << "Precision for axis: " << i << ": " << corr[i].prec << endl;
  }
}

//--------------------------------------------------------------

JoyDevice::ErrorCode JoyDevice::restoreCorr()
{
  if ( joyFd == -1 ) return JoyDevice::SUCCESS;

  if ( ::ioctl(joyFd, JSIOCSCORR, origCorr) == -1 )
    return JoyDevice::ERR_RESTORE_CORR;
  else
    return JoyDevice::SUCCESS;
}

//--------------------------------------------------------------

JoyDevice::~JoyDevice()
{
  close();
}

//--------------------------------------------------------------

bool JoyDevice::getEvent(JoyDevice::EventType &type, int &number, int &value)
{
  number = value = 0;

  int ret;

  fd_set readSet;

  FD_ZERO(&readSet);
  FD_SET(joyFd, &readSet);

  struct timeval timeout;
  timeout.tv_sec = 0;
  timeout.tv_usec = 100000;

  ret = ::select(joyFd + 1, &readSet, 0, 0, &timeout);

  if ( ret == 1 )  // got an event from the joystick
  {
    struct js_event e;

    if ( ::read(joyFd, &e, sizeof(struct js_event)) == sizeof(struct js_event) )
    {
      if ( e.type & JS_EVENT_BUTTON )
      {
        type = JoyDevice::BUTTON;
        value = e.value;
        number = e.number;

        return true;
      }

      if ( e.type & JS_EVENT_AXIS )
      {
        type = JoyDevice::AXIS;
        value = e.value;
        number = e.number;

        // store min, max values
        if ( e.value < amin[number] ) amin[number] = e.value;
        if ( e.value > amax[number] ) amax[number] = e.value;

        return true;
      }
    }
  }

  return false; // no event
}

//--------------------------------------------------------------

void JoyDevice::calcCorrection(int axis, int *min, int *center, int *max)
{
  const int MIN = 0;
  const int MAX = 1;

  double a, b, c, d;

  a = center[MIN]; // inputs.cmin[1];
  b = center[MAX]; // inputs.cmax[1];
  c = 32767.0 / (center[MIN] - min[MAX]); // (inputs.cmin[1] - inputs.cmax[0]);
  d = 32767.0 / (max[MIN] - center[MAX]); // (inputs.cmin[2] - inputs.cmax[1]);

  corr[axis].coef[0] = (int)rint(a);
  corr[axis].coef[1] = (int)rint(b);
  corr[axis].coef[2] = (int)rint(c*16384.0);
  corr[axis].coef[3] = (int)rint(d*16384.0);

  kdDebug() << "min min: " << min[0] << " max: " << min[1]  << endl;
  kdDebug() << "max min: " << max[0] << " max: " << max[1]  << endl;
  kdDebug() << "Correction values for axis: " << axis << ": "
            << corr[axis].coef[0] << ", "
            << corr[axis].coef[1] << ", "
            << corr[axis].coef[2] << ", "
            << corr[axis].coef[3] << endl;
}

//--------------------------------------------------------------
