/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

#ifdef SDL_JOYSTICK_OS2

/* OS/2 Joystick driver, contributed by Daniel Caetano */

#define INCL_DOSDEVICES
#define INCL_DOSDEVIOCTL
#define INCL_DOSMEMMGR
#include <os2.h>

/*****************************************************************
 * OS/2 Joystick driver defs. Based on docs at edm2.com and in old
 * drivers available at hobbes.nmsu.edu and www.os2site.com
 *****************************************************************/

#define GAME_GET_VERSION 0x01
#define GAME_GET_PARMS   0x02
#define GAME_GET_CALIB   0x04
#define GAME_GET_STATUS  0x10

#define IOCTL_CAT_USER   0x80
#define GAME_PORT_GET    0x20
#define GAME_PORT_RESET  0x60

#pragma pack(push,1)
typedef struct {
  USHORT  uJs_AxCnt, uJs_AyCnt; /* A joystick X/Y pos */
  USHORT  uJs_BxCnt, uJs_ByCnt; /* B joystick X/Y pos */
  USHORT  usJs_ButtonA1Cnt, usJs_ButtonA2Cnt;/* A1/A2 press cnts */
  USHORT  usJs_ButtonB1Cnt, usJs_ButtonB2Cnt;/* B1/B2 press cnts */
  UCHAR   ucJs_JoyStickMask;  /* mask of connected joystick pots */
  UCHAR   ucJs_ButtonStatus;  /* bits of switches down */
  ULONG   ulJs_Ticks;         /* total clock ticks (60 Hz) */
} GAME_PORT_STRUCT;
#pragma pack(pop)

typedef struct {
  USHORT  useA, useB;
  USHORT  mode;
  USHORT  format;
  USHORT  sampDiv;
  USHORT  scale;
  USHORT  res1, res2;
} GAME_PARM_STRUCT;

typedef struct {
  SHORT   x, y;
} GAME_2DPOS_STRUCT;

typedef struct {
  SHORT  lower, centre, upper;
} GAME_3POS_STRUCT;

typedef struct {
  GAME_3POS_STRUCT  Ax, Ay, Bx, By;
} GAME_CALIB_STRUCT;

typedef struct {
  GAME_2DPOS_STRUCT A, B;
  USHORT  butMask;
} GAME_DATA_STRUCT;

typedef struct {
  GAME_DATA_STRUCT  curdata;
  USHORT  b1cnt, b2cnt, b3cnt, b4cnt;
} GAME_STATUS_STRUCT;

/*****************************************************************/

#include "SDL_joystick.h"
#include "SDL_events.h"
#include "../SDL_sysjoystick.h"
#include "../SDL_joystick_c.h"

static HFILE hJoyPort = NULLHANDLE;	/* Joystick GAME$ Port Address */
#define MAX_JOYSTICKS	2	/* Maximum of two joysticks */
#define MAX_AXES	4			/* each joystick can have up to 4 axes */
#define MAX_BUTTONS	8		/* 8 buttons */
#define MAX_HATS	0			/* 0 hats - OS/2 doesn't support it */
#define MAX_BALLS	0			/* and 0 balls - OS/2 doesn't support it */
#define AXIS_MIN -32768		/* minimum value for axes coordinate */
#define AXIS_MAX 32767		/* maximum value for axes coordinate */
#define MAX_JOYNAME	128	/* Joystick name may have 128 characters */
/* limit axes to 256 possible positions to filter out noise */
#define JOY_AXIS_THRESHOLD (((AXIS_MAX)-(AXIS_MIN))/256)
/* Calc Button Flag for buttons A to D */
#define JOY_BUTTON_FLAG(n) (1<<n)

/* Joystick data... hold information about detected devices */
typedef struct SYS_JoyData_s
{
	Sint8	id;				/* Device ID          */
	char	szDeviceName[MAX_JOYNAME];	/* Device Name        */
	char	axes;				/* Number of axes     */
	char	buttons;			/* Number of buttons  */
	char	hats;				/* Number of buttons  */
	char	balls;				/* Number of buttons  */
	int	axes_min[MAX_AXES];		/* minimum callibration value for axes  */
	int	axes_med[MAX_AXES];		/* medium callibration value for axes   */
	int	axes_max[MAX_AXES];		/* maximum callibration value for axes  */
	int	buttoncalc[4];			/* Used for buttons 5, 6, 7 and 8.      */
} SYS_JoyData_t, *SYS_JoyData_p;

static SYS_JoyData_t SYS_JoyData[MAX_JOYSTICKS];

/* Structure used to convert data from OS/2 driver format to SDL format */
struct _transaxes
{
	int offset;					/* Center Offset */
	float scale1;				/* Center to left/up Scale */
	float scale2;				/* Center to right/down Scale */
};

struct joystick_hwdata
{
	Sint8		id;
	struct _transaxes	transaxes[MAX_AXES];
};

/* Structure used to get values from Joystick Environment Variable */
struct _joycfg
{
	char	name[MAX_JOYNAME];
	unsigned int	axes;
	unsigned int	buttons;
	unsigned int	hats;
	unsigned int	balls;
};

/* OS/2 Implementation Function Prototypes */
static int joyPortOpen(HFILE * hGame);
static void joyPortClose(HFILE * hGame);
static int joyGetData(const char *joyenv, char *name, char stopchar, size_t maxchars);
static int joyGetEnv(struct _joycfg * joydata);


/************************************************************************/
/* Function to scan the system for joysticks.									*/
/* This function should set SDL_numjoysticks to the number of available	*/
/* joysticks.  Joystick 0 should be the system default joystick.			*/
/* It should return 0, or -1 on an unrecoverable fatal error.				*/
/************************************************************************/
int SDL_SYS_JoystickInit(void)
{
	APIRET rc;	/* Generic OS/2 return code */
	GAME_PORT_STRUCT	stJoyStatus;		/* Joystick Status Structure */
	GAME_PARM_STRUCT	stGameParms;		/* Joystick Parameter Structure */
	GAME_CALIB_STRUCT	stGameCalib;		/* Calibration Struct */
	ULONG ulDataLen;					/* Size of data */
	ULONG ulLastTick;					/* Tick Counter for timing operations */
	Uint8 maxdevs;						/* Maximum number of devices */
	Uint8 numdevs;						/* Number of present devices */
	Uint8 maxbut;						/* Maximum number of buttons... */
	Uint8 i;						/* Temporary Count Vars */
	Uint8 ucNewJoystickMask;				/* Mask for Joystick Detection */
	struct _joycfg joycfg;					/* Joy Configuration from envvar */

	/* Open GAME$ port */
	if (joyPortOpen(&hJoyPort) < 0) return 0;	/* Cannot open... report no joystick */
	/* Get Max Number of Devices */
	ulDataLen = sizeof(stGameParms);
	rc = DosDevIOCtl(hJoyPort, IOCTL_CAT_USER, GAME_GET_PARMS,
			 NULL, 0, NULL, &stGameParms, ulDataLen, &ulDataLen); /* Ask device info */
	if (rc != 0)
	{
		joyPortClose(&hJoyPort);
		SDL_SetError("Could not read joystick port.");
		return -1;
	}
	maxdevs = 0;
	if (stGameParms.useA != 0) maxdevs++;
	if (stGameParms.useB != 0) maxdevs++;
	if (maxdevs > MAX_JOYSTICKS) maxdevs = MAX_JOYSTICKS;

	/* Defines min/max axes values (callibration) */
	ulDataLen = sizeof(stGameCalib);
	rc = DosDevIOCtl(hJoyPort, IOCTL_CAT_USER, GAME_GET_CALIB,
			 NULL, 0, NULL, &stGameCalib, ulDataLen, &ulDataLen);
	if (rc != 0)
	{
		joyPortClose(&hJoyPort);
		SDL_SetError("Could not read callibration data.");
		return -1;
	}

	/* Determine how many joysticks are active */
	numdevs = 0;	/* Points no device */
	ucNewJoystickMask = 0x0F;	/* read all 4 joystick axis */
	ulDataLen = sizeof(ucNewJoystickMask);
	rc = DosDevIOCtl(hJoyPort, IOCTL_CAT_USER, GAME_PORT_RESET,
			 &ucNewJoystickMask, ulDataLen, &ulDataLen, NULL, 0, NULL);
	if (rc == 0)
	{
		ulDataLen = sizeof(stJoyStatus);
		rc = DosDevIOCtl(hJoyPort, IOCTL_CAT_USER, GAME_PORT_GET,
				 NULL, 0, NULL, &stJoyStatus, ulDataLen, &ulDataLen);
		if (rc != 0)
		{
			joyPortClose(&hJoyPort);
			SDL_SetError("Could not call joystick port.");
			return -1;
		}
		ulLastTick = stJoyStatus.ulJs_Ticks;
		while (stJoyStatus.ulJs_Ticks == ulLastTick)
		{
			rc = DosDevIOCtl(hJoyPort, IOCTL_CAT_USER, GAME_PORT_GET,
					 NULL, 0, NULL, &stJoyStatus, ulDataLen, &ulDataLen);
		}
		if ((stJoyStatus.ucJs_JoyStickMask & 0x03) > 0) numdevs++;
		if (((stJoyStatus.ucJs_JoyStickMask >> 2) & 0x03) > 0) numdevs++;
	}

	if (numdevs > maxdevs) numdevs = maxdevs;

	/* If *any* joystick was detected... Let's configure SDL for them */
	if (numdevs > 0)
	{
		/* Verify if it is a "user defined" joystick */
		if (joyGetEnv(&joycfg))
		{
			GAME_3POS_STRUCT * axis[4];
			axis[0] = &stGameCalib.Ax;
			axis[1] = &stGameCalib.Ay;
			axis[2] = &stGameCalib.Bx;
			axis[3] = &stGameCalib.By;

			/* Say it has one device only (user defined is always one device only) */
			numdevs = 1;

			/* Define Device 0 as... */
			SYS_JoyData[0].id = 0;

			/* Define Number of Axes... up to 4 */
			if (joycfg.axes>MAX_AXES) joycfg.axes = MAX_AXES;
			SYS_JoyData[0].axes = joycfg.axes;

			/* Define number of buttons... 8 if 2 axes, 6 if 3 axes and 4 if 4 axes */
			maxbut = MAX_BUTTONS;
			if (joycfg.axes>2) maxbut -= ((joycfg.axes - 2)<<1); /* MAX_BUTTONS - 2*(axes-2) */
			if (joycfg.buttons > maxbut) joycfg.buttons = maxbut;
			SYS_JoyData[0].buttons = joycfg.buttons;

			/* Define number of hats */
			if (joycfg.hats > MAX_HATS) joycfg.hats = MAX_HATS;
			SYS_JoyData[0].hats = joycfg.hats;

			/* Define number of balls */
			if (joycfg.balls > MAX_BALLS) joycfg.balls = MAX_BALLS;
			SYS_JoyData[0].balls = joycfg.balls;

			/* Initialize Axes Callibration Values */
			for (i=0; i<joycfg.axes; i++)
			{
				SYS_JoyData[0].axes_min[i] = axis[i]->lower;
				SYS_JoyData[0].axes_med[i] = axis[i]->centre;
				SYS_JoyData[0].axes_max[i] = axis[i]->upper;
			}
			/* Initialize Buttons 5 to 8 structures */
			if (joycfg.buttons>=5) SYS_JoyData[0].buttoncalc[0] = ((axis[2]->lower+axis[3]->centre)>>1);
			if (joycfg.buttons>=6) SYS_JoyData[0].buttoncalc[1] = ((axis[3]->lower+axis[3]->centre)>>1);
			if (joycfg.buttons>=7) SYS_JoyData[0].buttoncalc[2] = ((axis[2]->upper+axis[3]->centre)>>1);
			if (joycfg.buttons>=8) SYS_JoyData[0].buttoncalc[3] = ((axis[3]->upper+axis[3]->centre)>>1);
			/* Intialize Joystick Name */
			SDL_strlcpy (SYS_JoyData[0].szDeviceName,joycfg.name, SDL_arraysize(SYS_JoyData[0].szDeviceName));
		}
		/* Default Init ... autoconfig */
		else
		{
			/* if two devices were detected... configure as Joy1 4 axis and Joy2 2 axis */
			if (numdevs == 2)
			{
				/* Define Device 0 as 4 axes, 4 buttons */
				SYS_JoyData[0].id=0;
				SYS_JoyData[0].axes = 4;
				SYS_JoyData[0].buttons = 4;
				SYS_JoyData[0].hats = 0;
				SYS_JoyData[0].balls = 0;
				SYS_JoyData[0].axes_min[0] = stGameCalib.Ax.lower;
				SYS_JoyData[0].axes_med[0] = stGameCalib.Ax.centre;
				SYS_JoyData[0].axes_max[0] = stGameCalib.Ax.upper;
				SYS_JoyData[0].axes_min[1] = stGameCalib.Ay.lower;
				SYS_JoyData[0].axes_med[1] = stGameCalib.Ay.centre;
				SYS_JoyData[0].axes_max[1] = stGameCalib.Ay.upper;
				SYS_JoyData[0].axes_min[2] = stGameCalib.Bx.lower;
				SYS_JoyData[0].axes_med[2] = stGameCalib.Bx.centre;
				SYS_JoyData[0].axes_max[2] = stGameCalib.Bx.upper;
				SYS_JoyData[0].axes_min[3] = stGameCalib.By.lower;
				SYS_JoyData[0].axes_med[3] = stGameCalib.By.centre;
				SYS_JoyData[0].axes_max[3] = stGameCalib.By.upper;
				/* Define Device 1 as 2 axes, 2 buttons */
				SYS_JoyData[1].id=1;
				SYS_JoyData[1].axes = 2;
				SYS_JoyData[1].buttons = 2;
				SYS_JoyData[1].hats = 0;
				SYS_JoyData[1].balls = 0;
				SYS_JoyData[1].axes_min[0] = stGameCalib.Bx.lower;
				SYS_JoyData[1].axes_med[0] = stGameCalib.Bx.centre;
				SYS_JoyData[1].axes_max[0] = stGameCalib.Bx.upper;
				SYS_JoyData[1].axes_min[1] = stGameCalib.By.lower;
				SYS_JoyData[1].axes_med[1] = stGameCalib.By.centre;
				SYS_JoyData[1].axes_max[1] = stGameCalib.By.upper;
			}
			/* One joystick only? */
			else
			{
				/* If it is joystick A... */
				if ((stJoyStatus.ucJs_JoyStickMask & 0x03) > 0)
				{
					/* Define Device 0 as 2 axes, 4 buttons */
					SYS_JoyData[0].id=0;
					SYS_JoyData[0].axes = 2;
					SYS_JoyData[0].buttons = 4;
					SYS_JoyData[0].hats = 0;
					SYS_JoyData[0].balls = 0;
					SYS_JoyData[0].axes_min[0] = stGameCalib.Ax.lower;
					SYS_JoyData[0].axes_med[0] = stGameCalib.Ax.centre;
					SYS_JoyData[0].axes_max[0] = stGameCalib.Ax.upper;
					SYS_JoyData[0].axes_min[1] = stGameCalib.Ay.lower;
					SYS_JoyData[0].axes_med[1] = stGameCalib.Ay.centre;
					SYS_JoyData[0].axes_max[1] = stGameCalib.Ay.upper;
				}
				/* If not, it is joystick B */
				else
				{
					/* Define Device 1 as 2 axes, 2 buttons */
					SYS_JoyData[0].id=1;
					SYS_JoyData[0].axes = 2;
					SYS_JoyData[0].buttons = 2;
					SYS_JoyData[0].hats = 0;
					SYS_JoyData[0].balls = 0;
					SYS_JoyData[0].axes_min[0] = stGameCalib.Bx.lower;
					SYS_JoyData[0].axes_med[0] = stGameCalib.Bx.centre;
					SYS_JoyData[0].axes_max[0] = stGameCalib.Bx.upper;
					SYS_JoyData[0].axes_min[1] = stGameCalib.By.lower;
					SYS_JoyData[0].axes_med[1] = stGameCalib.By.centre;
					SYS_JoyData[0].axes_max[1] = stGameCalib.By.upper;
				}
			}

			/* Hack to define Joystick Port Names */
			if (numdevs > maxdevs) numdevs = maxdevs;

			for (i = 0; i < numdevs; i++)
			{
				SDL_snprintf(SYS_JoyData[i].szDeviceName,
						SDL_arraysize(SYS_JoyData[i].szDeviceName),
						"Default Joystick %c", 'A'+SYS_JoyData[i].id);
			}
		}
	}
	/* Return the number of devices found */
	return numdevs;
}

/***********************************************************/
/* Function to get the device-dependent name of a joystick */
/***********************************************************/
const char *SDL_SYS_JoystickName(int index)
{
	/* No need to verify if device exists, already done in upper layer */
	return SYS_JoyData[index].szDeviceName;
}

/******************************************************************************/
/* Function to open a joystick for use.													*/
/* The joystick to open is specified by the index field of the joystick.		*/
/* This should fill the nbuttons and naxes fields of the joystick structure.	*/
/* It returns 0, or -1 if there is an error.												*/
/******************************************************************************/
int SDL_SYS_JoystickOpen(SDL_Joystick *joystick)
{
	int index;		/* Index shortcut for index in joystick structure */
	int i;			/* Generic Counter */

	/* allocate memory for system specific hardware data */
	joystick->hwdata = (struct joystick_hwdata *) SDL_calloc(1, sizeof(*joystick->hwdata));
	if (!joystick->hwdata)
	{
		SDL_OutOfMemory();
		return -1;
	}

	/* ShortCut Pointer */
	index = joystick->index;

	/* Define offsets and scales for all axes */
	joystick->hwdata->id = SYS_JoyData[index].id;
	for (i = 0; i < MAX_AXES; ++i)
	{
		if ((i < 2) || i < SYS_JoyData[index].axes)
		{
			joystick->hwdata->transaxes[i].offset = ((AXIS_MAX + AXIS_MIN)>>1) - SYS_JoyData[index].axes_med[i];
			joystick->hwdata->transaxes[i].scale1 = (float)abs((AXIS_MIN/SYS_JoyData[index].axes_min[i]));
			joystick->hwdata->transaxes[i].scale2 = (float)abs((AXIS_MAX/SYS_JoyData[index].axes_max[i]));
		}
		else
		{
			joystick->hwdata->transaxes[i].offset = 0;
			joystick->hwdata->transaxes[i].scale1 = 1.0; /* Just in case */
			joystick->hwdata->transaxes[i].scale2 = 1.0; /* Just in case */
		}
	}

	/* fill nbuttons, naxes, and nhats fields */
	joystick->nbuttons = SYS_JoyData[index].buttons;
	joystick->naxes = SYS_JoyData[index].axes;

	/* joystick->nhats = SYS_JoyData[index].hats; */
	joystick->nhats = 0; /* No support for hats at this time */

	/* joystick->nballs = SYS_JoyData[index].balls; */
	joystick->nballs = 0; /* No support for balls at this time */

	return 0;
}

/***************************************************************************/
/* Function to update the state of a joystick - called as a device poll.	*/
/* This function shouldn't update the joystick structure directly,			*/
/* but instead should call SDL_PrivateJoystick*() to deliver events			*/
/* and update joystick device state.													*/
/***************************************************************************/
void SDL_SYS_JoystickUpdate(SDL_Joystick *joystick)
{
	APIRET rc;	/* Generic OS/2 return code */
	int index;					/* index shortcurt to joystick index */
	int i;						/* Generic counter */
	int normbut;					/* Number of buttons reported by joystick */
	int corr;							/* Correction for button names */
	Sint16 value, change;					/* Values used to update axis values */
	struct _transaxes *transaxes;			/* Shortcut for Correction structure */
	Uint32 pos[MAX_AXES];				/* Vector to inform the Axis status */
	ULONG ulDataLen;					/* Size of data */
	GAME_STATUS_STRUCT stGameStatus;		/* Joystick Status Structure */

	ulDataLen = sizeof(stGameStatus);
	rc = DosDevIOCtl(hJoyPort, IOCTL_CAT_USER, GAME_GET_STATUS,
			 NULL, 0, NULL, &stGameStatus, ulDataLen, &ulDataLen);
	if (rc != 0)
	{
		SDL_SetError("Could not read joystick status.");
		return; /* Could not read data */
	}

	/* Shortcut pointer */
	index = joystick->index;

	/* joystick motion events */

	if (SYS_JoyData[index].id == 0)
	{
		pos[0] = stGameStatus.curdata.A.x;
		pos[1] = stGameStatus.curdata.A.y;
		if (SYS_JoyData[index].axes >= 3) pos[2] = stGameStatus.curdata.B.x;
		else pos[2] = 0;
		if (SYS_JoyData[index].axes >= 4) pos[3] = stGameStatus.curdata.B.y;
		else pos[3] = 0;
		/* OS/2 basic drivers do not support more than 4 axes joysticks */
	}
	else if (SYS_JoyData[index].id == 1)
	{
		pos[0] = stGameStatus.curdata.B.x;
		pos[1] = stGameStatus.curdata.B.y;
		pos[2] = 0;
		pos[3] = 0;
	}

	/* Corrects the movements using the callibration */
	transaxes = joystick->hwdata->transaxes;
	for (i = 0; i < joystick->naxes; i++)
	{
		value = pos[i] + transaxes[i].offset;
		if (value < 0)
		{
			value *= transaxes[i].scale1;
			if (value > 0) value = AXIS_MIN;
		}
		else
		{
			value *= transaxes[i].scale2;
			if (value < 0) value = AXIS_MAX;
		}
		change = (value - joystick->axes[i]);
		if ((change < -JOY_AXIS_THRESHOLD) || (change > JOY_AXIS_THRESHOLD))
		{
			SDL_PrivateJoystickAxis(joystick, (Uint8)i, (Sint16)value);
		}
	}

	/* joystick button A to D events */
	if (SYS_JoyData[index].id == 1) corr = 2;
	else corr = 0;
	normbut = 4;	/* Number of normal buttons */
	if (joystick->nbuttons < normbut) normbut = joystick->nbuttons;
	for (i = corr; (i-corr) < normbut; ++i)
	{
		/*
		Button A: 1110 0000
		Button B: 1101 0000
		Button C: 1011 0000
		Button D: 0111 0000
		*/
		if ((~stGameStatus.curdata.butMask)>>4 & JOY_BUTTON_FLAG(i))
		{
			if (! joystick->buttons[i-corr])
			{
				SDL_PrivateJoystickButton(joystick, (Uint8)(i-corr), SDL_PRESSED);
			}
		}
		else
		{
			if ( joystick->buttons[i-corr])
			{
				SDL_PrivateJoystickButton(joystick, (Uint8)(i-corr), SDL_RELEASED);
			}
		}
	}

	/* Joystick button E to H buttons */
	/*
	Button E: Axis 2 X Left
	Button F: Axis 2 Y Up
	Button G: Axis 2 X Right
	Button H: Axis 2 Y Down
	*/
	if (joystick->nbuttons >= 5)
	{
		if (stGameStatus.curdata.B.x < SYS_JoyData[index].buttoncalc[0]) SDL_PrivateJoystickButton(joystick, (Uint8)4, SDL_PRESSED);
		else SDL_PrivateJoystickButton(joystick, (Uint8)4, SDL_RELEASED);
	}
	if (joystick->nbuttons >= 6)
	{
		if (stGameStatus.curdata.B.y < SYS_JoyData[index].buttoncalc[1]) SDL_PrivateJoystickButton(joystick, (Uint8)5, SDL_PRESSED);
		else SDL_PrivateJoystickButton(joystick, (Uint8)5, SDL_RELEASED);
	}
	if (joystick->nbuttons >= 7)
	{
		if (stGameStatus.curdata.B.x > SYS_JoyData[index].buttoncalc[2]) SDL_PrivateJoystickButton(joystick, (Uint8)6, SDL_PRESSED);
		else SDL_PrivateJoystickButton(joystick, (Uint8)6, SDL_RELEASED);
	}
	if (joystick->nbuttons >= 8)
	{
		if (stGameStatus.curdata.B.y > SYS_JoyData[index].buttoncalc[3]) SDL_PrivateJoystickButton(joystick, (Uint8)7, SDL_PRESSED);
		else SDL_PrivateJoystickButton(joystick, (Uint8)7, SDL_RELEASED);
	}

	/* joystick hat events */
	/* Not Supported under OS/2 */
	/* joystick ball events */
	/* Not Supported under OS/2 */
}

/******************************************/
/* Function to close a joystick after use */
/******************************************/
void SDL_SYS_JoystickClose(SDL_Joystick *joystick)
{
	/* free system specific hardware data */
	SDL_free(joystick->hwdata);
}

/********************************************************************/
/* Function to perform any system-specific joystick related cleanup */
/********************************************************************/
void SDL_SYS_JoystickQuit(void)
{
	joyPortClose(&hJoyPort);
}


/************************/
/* OS/2 Implementations */
/************************/

/*****************************************/
/* Open Joystick Port, if not opened yet */
/*****************************************/
static int joyPortOpen(HFILE * hGame)
{
	APIRET	rc;				/* Generic Return Code */
	ULONG		ulAction;		/* ? */
	ULONG		ulVersion;		/* Version of joystick driver */
	ULONG		ulDataLen;		/* Size of version data */

	/* Verifies if joyport is not already open... */
	if (*hGame != NULLHANDLE) return 0;

	/* Open GAME$ for read */
	rc = DosOpen("GAME$   ", hGame, &ulAction, 0, FILE_READONLY,
		     FILE_OPEN, OPEN_ACCESS_READONLY | OPEN_SHARE_DENYNONE, NULL);
	if (rc != 0)
	{
		SDL_SetError("Could not open Joystick Port.");
		return -1;
	}

	/* Get Joystick Driver Version... must be 2.0 or higher */
	ulVersion = 0;
	ulDataLen = sizeof(ulVersion);
	rc = DosDevIOCtl(*hGame, IOCTL_CAT_USER, GAME_GET_VERSION,
			 NULL, 0, NULL, &ulVersion, ulDataLen, &ulDataLen);
	if (rc != 0)
	{
		joyPortClose(hGame);
		SDL_SetError("Could not get Joystick Driver version.");
		return -1;
	}
	if (ulVersion < 0x20)
	{
		joyPortClose(hGame);
		SDL_SetError("Driver too old. At least IBM driver version 2.0 required.");
		return -1;
	}
	return 0;
}

/****************************/
/* Close JoyPort, if opened */
/****************************/
static void joyPortClose(HFILE * hGame)
{
	if (*hGame != NULLHANDLE) DosClose(*hGame);
	*hGame = NULLHANDLE;
}

/***************************/
/* Get SDL Joystick EnvVar */
/***************************/
static int joyGetEnv(struct _joycfg * joydata)
{
	const char *joyenv;		/* Pointer to tested character */
	char tempnumber[5];		/* Temporary place to put numeric texts */

	joyenv = SDL_getenv("SDL_OS2_JOYSTICK");
	if (joyenv == NULL) return 0;

	/* Joystick Environment is defined! */
	while (*joyenv == ' ' && *joyenv != 0) joyenv++; /* jump spaces... */

	/* If the string name starts with '... get if fully */
	if (*joyenv == '\'') {
		joyenv++;
		joyenv += joyGetData(joyenv,joydata->name,'\'',sizeof(joydata->name));
	}
	/* If not, get it until the next space */
	else if (*joyenv == '\"') {
		joyenv++;
		joyenv += joyGetData(joyenv,joydata->name,'\"',sizeof(joydata->name));
	}
	else {
		joyenv += joyGetData(joyenv,joydata->name, ' ',sizeof(joydata->name));
	}

	/* Now get the number of axes */
	while (*joyenv == ' ' && *joyenv != 0) joyenv++; /* jump spaces... */
	joyenv += joyGetData(joyenv,tempnumber,' ',sizeof(tempnumber));
	joydata->axes = atoi(tempnumber);

	/* Now get the number of buttons */
	while (*joyenv == ' ' && *joyenv != 0) joyenv++; /* jump spaces... */
	joyenv += joyGetData(joyenv,tempnumber,' ',sizeof(tempnumber));
	joydata->buttons = atoi(tempnumber);

	/* Now get the number of hats */
	while (*joyenv == ' ' && *joyenv != 0) joyenv++; /* jump spaces... */
	joyenv += joyGetData(joyenv,tempnumber,' ',sizeof(tempnumber));
	joydata->hats = atoi(tempnumber);

	/* Now get the number of balls */
	while (*joyenv==' ' && *joyenv != 0) joyenv++; /* jump spaces... */
	joyenv += joyGetData(joyenv,tempnumber,' ',sizeof(tempnumber));
	joydata->balls = atoi(tempnumber);
	return 1;
}

/************************************************************************/
/* Get a text from in the string starting in joyenv until it finds		*/
/* the stopchar or maxchars is reached. The result is placed in name.	*/
/************************************************************************/
static int joyGetData(const char *joyenv, char *name, char stopchar, size_t maxchars)
{
	char *nameptr;			/* Pointer to the selected character */
	int chcnt = 0;			/* Count how many characters where copied */

	nameptr = name;
	while (*joyenv!=stopchar && *joyenv!=0)
	{
		if (nameptr < (name + (maxchars-1)))
		{
			*nameptr = *joyenv; /* Only copy if smaller than maximum */
			nameptr++;
		}
		chcnt++;
		joyenv++;
	}
	if (*joyenv == stopchar)
	{
		joyenv++; /* Jump stopchar */
		chcnt++;
	}
	*nameptr = 0; /* Mark last byte */
	return chcnt;
}

#endif /* SDL_JOYSTICK_OS2 */
