/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997-2011 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"

/* This is the joystick API for Simple DirectMedia Layer */

#include "SDL_events.h"

#include "SDL_sysjoystick.h"

#include "SDL_joystick_c.h"

#if !SDL_EVENTS_DISABLED

#include "../events/SDL_events_c.h"

#endif

Uint8 SDL_numjoysticks = 0;

SDL_Joystick **SDL_joysticks = NULL;

static SDL_Joystick *default_joystick = NULL;

int

SDL_JoystickInit(void)

{

    int arraylen;

    int status;

    SDL_numjoysticks = 0;

    status = SDL_SYS_JoystickInit();

    if (status >= 0) {

        arraylen = (status + 1) * sizeof(*SDL_joysticks);

        SDL_joysticks = (SDL_Joystick **) SDL_malloc(arraylen);

        if (SDL_joysticks == NULL) {

            SDL_numjoysticks = 0;

        } else {

            SDL_memset(SDL_joysticks, 0, arraylen);

            SDL_numjoysticks = status;

        }

        status = 0;

    }

    default_joystick = NULL;

    return (status);

}

/*

 * Count the number of joysticks attached to the system

 */

int

SDL_NumJoysticks(void)

{

    return SDL_numjoysticks;

}

/*

 * Get the implementation dependent name of a joystick

 */

const char *

SDL_JoystickName(int device_index)

{

    if ((device_index < 0) || (device_index >= SDL_numjoysticks)) {

        SDL_SetError("There are %d joysticks available", SDL_numjoysticks);

        return (NULL);

    }

    return (SDL_SYS_JoystickName(device_index));

}

/*

 * Open a joystick for use - the index passed as an argument refers to

 * the N'th joystick on the system.  This index is the value which will

 * identify this joystick in future joystick events.

 *

 * This function returns a joystick identifier, or NULL if an error occurred.

 */

SDL_Joystick *

SDL_JoystickOpen(int device_index)

{

    int i;

    SDL_Joystick *joystick;

    if ((device_index < 0) || (device_index >= SDL_numjoysticks)) {

        SDL_SetError("There are %d joysticks available", SDL_numjoysticks);

        return (NULL);

    }

    /* If the joystick is already open, return it */

    for (i = 0; SDL_joysticks[i]; ++i) {

        if (device_index == SDL_joysticks[i]->index) {

            joystick = SDL_joysticks[i];

            ++joystick->ref_count;

            return (joystick);

        }

    }

    /* Create and initialize the joystick */

    joystick = (SDL_Joystick *) SDL_malloc((sizeof *joystick));

    if (joystick == NULL) {

        SDL_OutOfMemory();

        return NULL;

    }

    SDL_memset(joystick, 0, (sizeof *joystick));

    joystick->index = device_index;

    if (SDL_SYS_JoystickOpen(joystick) < 0) {

        SDL_free(joystick);

        return NULL;

    }

    if (joystick->naxes > 0) {

        joystick->axes = (Sint16 *) SDL_malloc

            (joystick->naxes * sizeof(Sint16));

    }

    if (joystick->nhats > 0) {

        joystick->hats = (Uint8 *) SDL_malloc

            (joystick->nhats * sizeof(Uint8));

    }

    if (joystick->nballs > 0) {

        joystick->balls = (struct balldelta *) SDL_malloc

            (joystick->nballs * sizeof(*joystick->balls));

    }

    if (joystick->nbuttons > 0) {

        joystick->buttons = (Uint8 *) SDL_malloc

            (joystick->nbuttons * sizeof(Uint8));

    }

    if (((joystick->naxes > 0) && !joystick->axes)

        || ((joystick->nhats > 0) && !joystick->hats)

        || ((joystick->nballs > 0) && !joystick->balls)

        || ((joystick->nbuttons > 0) && !joystick->buttons)) {

        SDL_OutOfMemory();

        SDL_JoystickClose(joystick);

        return NULL;

    }

    if (joystick->axes) {

        SDL_memset(joystick->axes, 0, joystick->naxes * sizeof(Sint16));

    }

    if (joystick->hats) {

        SDL_memset(joystick->hats, 0, joystick->nhats * sizeof(Uint8));

    }

    if (joystick->balls) {

        SDL_memset(joystick->balls, 0,

            joystick->nballs * sizeof(*joystick->balls));

    }

    if (joystick->buttons) {

        SDL_memset(joystick->buttons, 0, joystick->nbuttons * sizeof(Uint8));

    }

    /* Add joystick to list */

    ++joystick->ref_count;

    for (i = 0; SDL_joysticks[i]; ++i)

        /* Skip to next joystick */ ;

    SDL_joysticks[i] = joystick;

    return (joystick);

}

/*

 * Returns 1 if the joystick has been opened, or 0 if it has not.

 */

int

SDL_JoystickOpened(int device_index)

{

    int i, opened;

    opened = 0;

    for (i = 0; SDL_joysticks[i]; ++i) {

        if (SDL_joysticks[i]->index == (Uint8) device_index) {

            opened = 1;

            break;

        }

    }

    return (opened);

}

/*

 * Checks to make sure the joystick is valid.

 */

int

SDL_PrivateJoystickValid(SDL_Joystick ** joystick)

{

    int valid;

    if (*joystick == NULL) {

        *joystick = default_joystick;

    }

    if (*joystick == NULL) {

        SDL_SetError("Joystick hasn't been opened yet");

        valid = 0;

    } else {

        valid = 1;

    }

    return valid;

}

/*

 * Get the device index of an opened joystick.

 */

int

SDL_JoystickIndex(SDL_Joystick * joystick)

{

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (-1);

    }

    return (joystick->index);

}

/*

 * Get the number of multi-dimensional axis controls on a joystick

 */

int

SDL_JoystickNumAxes(SDL_Joystick * joystick)

{

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (-1);

    }

    return (joystick->naxes);

}

/*

 * Get the number of hats on a joystick

 */

int

SDL_JoystickNumHats(SDL_Joystick * joystick)

{

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (-1);

    }

    return (joystick->nhats);

}

/*

 * Get the number of trackballs on a joystick

 */

int

SDL_JoystickNumBalls(SDL_Joystick * joystick)

{

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (-1);

    }

    return (joystick->nballs);

}

/*

 * Get the number of buttons on a joystick

 */

int

SDL_JoystickNumButtons(SDL_Joystick * joystick)

{

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (-1);

    }

    return (joystick->nbuttons);

}

/*

 * Get the current state of an axis control on a joystick

 */

Sint16

SDL_JoystickGetAxis(SDL_Joystick * joystick, int axis)

{

    Sint16 state;

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (0);

    }

    if (axis < joystick->naxes) {

        state = joystick->axes[axis];

    } else {

        SDL_SetError("Joystick only has %d axes", joystick->naxes);

        state = 0;

    }

    return (state);

}

/*

 * Get the current state of a hat on a joystick

 */

Uint8

SDL_JoystickGetHat(SDL_Joystick * joystick, int hat)

{

    Uint8 state;

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (0);

    }

    if (hat < joystick->nhats) {

        state = joystick->hats[hat];

    } else {

        SDL_SetError("Joystick only has %d hats", joystick->nhats);

        state = 0;

    }

    return (state);

}

/*

 * Get the ball axis change since the last poll

 */

int

SDL_JoystickGetBall(SDL_Joystick * joystick, int ball, int *dx, int *dy)

{

    int retval;

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (-1);

    }

    retval = 0;

    if (ball < joystick->nballs) {

        if (dx) {

            *dx = joystick->balls[ball].dx;

        }

        if (dy) {

            *dy = joystick->balls[ball].dy;

        }

        joystick->balls[ball].dx = 0;

        joystick->balls[ball].dy = 0;

    } else {

        SDL_SetError("Joystick only has %d balls", joystick->nballs);

        retval = -1;

    }

    return (retval);

}

/*

 * Get the current state of a button on a joystick

 */

Uint8

SDL_JoystickGetButton(SDL_Joystick * joystick, int button)

{

    Uint8 state;

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return (0);

    }

    if (button < joystick->nbuttons) {

        state = joystick->buttons[button];

    } else {

        SDL_SetError("Joystick only has %d buttons", joystick->nbuttons);

        state = 0;

    }

    return (state);

}

/*

 * Close a joystick previously opened with SDL_JoystickOpen()

 */

void

SDL_JoystickClose(SDL_Joystick * joystick)

{

    int i;

    if (!SDL_PrivateJoystickValid(&joystick)) {

        return;

    }

    /* First decrement ref count */

    if (--joystick->ref_count > 0) {

        return;

    }

    if (joystick == default_joystick) {

        default_joystick = NULL;

    }

    SDL_SYS_JoystickClose(joystick);

    /* Remove joystick from list */

    for (i = 0; SDL_joysticks[i]; ++i) {

        if (joystick == SDL_joysticks[i]) {

            SDL_memmove(&SDL_joysticks[i], &SDL_joysticks[i + 1],

                        (SDL_numjoysticks - i) * sizeof(joystick));

            break;

        }

    }

    /* Free the data associated with this joystick */

    if (joystick->axes) {

        SDL_free(joystick->axes);

    }

    if (joystick->hats) {

        SDL_free(joystick->hats);

    }

    if (joystick->balls) {

        SDL_free(joystick->balls);

    }

    if (joystick->buttons) {

        SDL_free(joystick->buttons);

    }

    SDL_free(joystick);

}

void

SDL_JoystickQuit(void)

{

    /* Stop the event polling */

    SDL_numjoysticks = 0;

    /* Quit the joystick setup */

    SDL_SYS_JoystickQuit();

    if (SDL_joysticks) {

        SDL_free(SDL_joysticks);

        SDL_joysticks = NULL;

    }

}

/* These are global for SDL_sysjoystick.c and SDL_events.c */

int

SDL_PrivateJoystickAxis(SDL_Joystick * joystick, Uint8 axis, Sint16 value)

{

    int posted;

    /* Update internal joystick state */

    joystick->axes[axis] = value;

    /* Post the event, if desired */

    posted = 0;

#if !SDL_EVENTS_DISABLED

    if (SDL_GetEventState(SDL_JOYAXISMOTION) == SDL_ENABLE) {

        SDL_Event event;

        event.type = SDL_JOYAXISMOTION;

        event.jaxis.which = joystick->index;

        event.jaxis.axis = axis;

        event.jaxis.value = value;

        if ((SDL_EventOK == NULL)

            || (*SDL_EventOK) (SDL_EventOKParam, &event)) {

            posted = 1;

            SDL_PushEvent(&event);

        }

    }

#endif /* !SDL_EVENTS_DISABLED */

    return (posted);

}

int

SDL_PrivateJoystickHat(SDL_Joystick * joystick, Uint8 hat, Uint8 value)

{

    int posted;

    /* Update internal joystick state */

    joystick->hats[hat] = value;

    /* Post the event, if desired */

    posted = 0;

#if !SDL_EVENTS_DISABLED

    if (SDL_GetEventState(SDL_JOYHATMOTION) == SDL_ENABLE) {

        SDL_Event event;

        event.jhat.type = SDL_JOYHATMOTION;

        event.jhat.which = joystick->index;

        event.jhat.hat = hat;

        event.jhat.value = value;

        if ((SDL_EventOK == NULL)

            || (*SDL_EventOK) (SDL_EventOKParam, &event)) {

            posted = 1;

            SDL_PushEvent(&event);

        }

    }

#endif /* !SDL_EVENTS_DISABLED */

    return (posted);

}

int

SDL_PrivateJoystickBall(SDL_Joystick * joystick, Uint8 ball,

                        Sint16 xrel, Sint16 yrel)

{

    int posted;

    /* Update internal mouse state */

    joystick->balls[ball].dx += xrel;

    joystick->balls[ball].dy += yrel;

    /* Post the event, if desired */

    posted = 0;

#if !SDL_EVENTS_DISABLED

    if (SDL_GetEventState(SDL_JOYBALLMOTION) == SDL_ENABLE) {

        SDL_Event event;

        event.jball.type = SDL_JOYBALLMOTION;

        event.jball.which = joystick->index;

        event.jball.ball = ball;

        event.jball.xrel = xrel;

        event.jball.yrel = yrel;