/*
Copyright (C) 2010 skuller.net

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 "common.h"
#include "sys_public.h"
#include "qal_api.h"
#include <AL/alc.h>

#define QALC_IMP \
    QAL(LPALCCREATECONTEXT, alcCreateContext); \
    QAL(LPALCMAKECONTEXTCURRENT, alcMakeContextCurrent); \
    QAL(LPALCPROCESSCONTEXT, alcProcessContext); \
    QAL(LPALCSUSPENDCONTEXT, alcSuspendContext); \
    QAL(LPALCDESTROYCONTEXT, alcDestroyContext); \
    QAL(LPALCGETCURRENTCONTEXT, alcGetCurrentContext); \
    QAL(LPALCGETCONTEXTSDEVICE, alcGetContextsDevice); \
    QAL(LPALCOPENDEVICE, alcOpenDevice); \
    QAL(LPALCCLOSEDEVICE, alcCloseDevice); \
    QAL(LPALCGETERROR, alcGetError); \
    QAL(LPALCISEXTENSIONPRESENT, alcIsExtensionPresent); \
    QAL(LPALCGETPROCADDRESS, alcGetProcAddress); \
    QAL(LPALCGETENUMVALUE, alcGetEnumValue); \
    QAL(LPALCGETSTRING, alcGetString); \
    QAL(LPALCGETINTEGERV, alcGetIntegerv); \
    QAL(LPALCCAPTUREOPENDEVICE, alcCaptureOpenDevice); \
    QAL(LPALCCAPTURECLOSEDEVICE, alcCaptureCloseDevice); \
    QAL(LPALCCAPTURESTART, alcCaptureStart); \
    QAL(LPALCCAPTURESTOP, alcCaptureStop); \
    QAL(LPALCCAPTURESAMPLES, alcCaptureSamples);

static cvar_t   *al_driver;
static cvar_t   *al_device;

static void *handle;
static ALCdevice *device;
static ALCcontext *context;

#define QAL(type,func)  static type q##func;
QALC_IMP
#undef QAL

#define QAL(type,func)  type q##func;
QAL_IMP
#undef QAL

void QAL_Shutdown(void)
{
    if (context) {
        qalcMakeContextCurrent(NULL);
        qalcDestroyContext(context);
        context = NULL;
    }
    if (device) {
        qalcCloseDevice(device);
        device = NULL;
    }

#define QAL(type,func)  q##func = NULL;
    QALC_IMP
    QAL_IMP
#undef QAL

    Sys_FreeLibrary(handle);
    handle = NULL;

    al_driver->flags &= ~CVAR_SOUND;
    al_device->flags &= ~CVAR_SOUND;
}

qboolean QAL_Init(void)
{
    al_driver = Cvar_Get("al_driver", DEFAULT_OPENAL_DRIVER, CVAR_SOUND);
    al_device = Cvar_Get("al_device", "", CVAR_SOUND);

    Sys_LoadLibrary(al_driver->string, NULL, &handle);
    if (!handle) {
        return qfalse;
    }

#define QAL(type, func)  q##func = Sys_GetProcAddress(handle, #func);
    QALC_IMP
    QAL_IMP
#undef QAL

    Com_DPrintf("...opening OpenAL device: ");
    device = qalcOpenDevice(al_device->string[0] ? al_device->string : NULL);
    if (!device) {
        goto fail;
    }
    Com_DPrintf("ok\n");

    Com_DPrintf("...creating OpenAL context: ");
    context = qalcCreateContext(device, NULL);
    if (!context) {
        goto fail;
    }
    Com_DPrintf("ok\n");

    Com_DPrintf("...making context current: ");
    if (!qalcMakeContextCurrent(context)) {
        goto fail;
    }
    Com_DPrintf("ok\n");

    al_driver->flags |= CVAR_SOUND;
    al_device->flags |= CVAR_SOUND;

    return qtrue;

fail:
    Com_DPrintf("failed\n");
    QAL_Shutdown();
    return qfalse;
}