* OpenAL Bridge - a simple portable library for OpenAL interface

* Copyright (c) 2009 Vittorio Giovara <vittorio.giovara@gmail.com>

*

* This program 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; version 2 of the License

*

* 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 Lesser General Public License for more details.

*

* You should have received a copy of the GNU Lesser 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

*/

/*Sources are points emitting sound*/

ALuint *Sources;

/*Buffers hold sound data*/

ALuint *Buffers;

/*index for Sources and Buffers*/

ALuint globalindex, globalsize, increment;

ALboolean openalReady = AL_FALSE;

ALfloat old_gain;

int openal_init(int memorysize) {

    /*Initialize an OpenAL contex and allocate memory space for data and buffers*/

    ALCcontext *context;

    ALCdevice *device;

    // set the memory dimentsion and the increment width when reallocating

    if (memorysize <= 0)

        globalsize = 50;

    else

        globalsize = memorysize;

    increment = globalsize;

    // reuse old context but keep the new value for increment

    if (openalReady == AL_TRUE) {

        err_msg("(%s) WARN - already initialized", prog);

        return 0;

    // open hardware device if present

    device = alcOpenDevice(NULL);

    if (device == NULL) {

        errno = ENODEV;

        err_ret("(%s) WARN - failed to open sound device, using software renderer", prog);

        device = alcOpenDevice("Generic Software");

        if (device == NULL) {

            err_ret("(%s) ERROR - failed to open sound software device, sound will be disabled", prog);

            return -1;

    }

    err_msg("(%s) INFO - Output device: %s", prog, alcGetString(device, ALC_DEVICE_SPECIFIER));

    context = alcCreateContext(device, NULL);

    alcMakeContextCurrent(context);

    alcProcessContext(context);

    if (AL_NO_ERROR != alGetError()) {

        err_msg("(%s) ERROR - Failed to create a new contex",prog);

        return -2;

    // allocate memory space for buffers and sources

    Buffers = (ALuint*) Malloc(sizeof(ALuint)*globalsize);

    Sources = (ALuint*) Malloc(sizeof(ALuint)*globalsize);

    // set the listener gain, position (on xyz axes), velocity (one value for each axe) and orientation

    // Position, Velocity and Orientation of the listener

    ALfloat ListenerPos[] = {0.0, 0.0, 0.0};

    ALfloat ListenerVel[] = {0.0, 0.0, 0.0};

    ALfloat ListenerOri[] = {0.0, 0.0, -1.0,  0.0, 1.0, 0.0};

    alListenerf (AL_GAIN,        1.0f       );

    alListenerfv(AL_POSITION,    ListenerPos);

    alListenerfv(AL_VELOCITY,    ListenerVel);

    alListenerfv(AL_ORIENTATION, ListenerOri);

    if (AL_NO_ERROR != alGetError()) {

        err_msg("(%s) ERROR - Failed to set Listener properties",prog);

        return -3;

    }

    openalReady = AL_TRUE;

    alGetError();  // clear any AL errors beforehand

    return AL_TRUE;

}

void openal_close (void) {

    /*Stop all sounds, deallocate all memory and close OpenAL */

    ALCcontext *context;

    ALCdevice  *device;

    if (openalReady == AL_FALSE) {

        errno = EPERM;

        err_ret("(%s) WARN - OpenAL not initialized", prog);

    alSourceStopv	(globalsize, Sources);

    alDeleteSources (globalsize, Sources);

    alDeleteBuffers (globalsize, Buffers);

    free(Sources);

    free(Buffers);

    context = alcGetCurrentContext();

    device  = alcGetContextsDevice(context);

    alcMakeContextCurrent(NULL);

    alcDestroyContext(context);

    alcCloseDevice(device);

    openalReady = AL_FALSE;

    err_msg("(%s) INFO - closed", prog);

    return;

}

ALboolean openal_ready(void) {

    return openalReady;

}

void helper_realloc (void) {

    /*expands allocated memory when loading more sound files than expected*/

    int oldsize = globalsize;

    globalsize += increment;

    err_msg("(%s) INFO - Realloc in process from %d to %d\n", prog, oldsize, globalsize);

    Buffers = (ALuint*) Realloc(Buffers, sizeof(ALuint)*globalsize);

    Sources = (ALuint*) Realloc(Sources, sizeof(ALuint)*globalsize);

    return;

}

int openal_loadfile (const char *filename){

    /*Open a file, load into memory and allocate the Source buffer for playing*/

    ALfloat SourcePos[] = { 0.0, 0.0, 0.0 }; /*Position of the source sound*/

    ALfloat SourceVel[] = { 0.0, 0.0, 0.0 }; /*Velocity of the source sound*/

    ALenum format;

    ALsizei bitsize, freq;

    char *data;

    uint32_t fileformat;

    ALenum error;

    FILE *fp;

    if (openalReady == AL_FALSE) {

        err_msg("(%s) WARN - not initialized", prog);

        return -1;

    }

    /*when the buffers are all used, we can expand memory to accept new files*/

    if (globalindex == globalsize)

        helper_realloc();

    /*detect the file format, as written in the first 4 bytes of the header*/

    fp = Fopen (filename, "rb");

    if (fp == NULL)

        return -2;

    error = fread (&fileformat, sizeof(uint32_t), 1, fp);

    fclose (fp);

    if (error < 0) {

        err_msg("(%s) ERROR - File %s is too short", prog, filename);

        return -3;

    }

    /*prepare the buffer to receive data*/

    alGenBuffers(1, &Buffers[globalindex]);

    if (AL_NO_ERROR != alGetError()) {

        err_msg("(%s) ERROR - Failed to allocate memory for buffers",prog);

        return -4;

    }

    /*prepare the source to emit sound*/

    alGenSources(1, &Sources[globalindex]);

    if (AL_NO_ERROR != alGetError()) {

        err_msg("(%s) ERROR - Failed to allocate memory for sources",prog);

        return -5;

    }

    switch (ENDIAN_BIG_32(fileformat)) {

        case OGG_FILE_FORMAT:

            error = load_oggvorbis (filename, &format, &data, &bitsize, &freq);

            break;

        case WAV_FILE_FORMAT:

            error = load_wavpcm (filename, &format, &data, &bitsize, &freq);

            break;

        default:

            err_msg ("(%s) ERROR - File format (%08X) not supported", prog, ENDIAN_BIG_32(fileformat));

            break;

    //copy pcm data in one buffer and free it

    alBufferData(Buffers[globalindex], format, data, bitsize, freq);

    free(data);

    if (AL_NO_ERROR != alGetError()) {

        err_msg("(%s) ERROR - Failed to write data to buffers",prog);

        return -6;

    /*set source properties that it will use when it's in playback*/

    alSourcei (Sources[globalindex], AL_BUFFER,   Buffers[globalindex]  );

    alSourcef (Sources[globalindex], AL_PITCH,    1.0f                  );

    alSourcef (Sources[globalindex], AL_GAIN,     1.0f                  );

    alSourcefv(Sources[globalindex], AL_POSITION, SourcePos             );

    alSourcefv(Sources[globalindex], AL_VELOCITY, SourceVel             );

    alSourcei (Sources[globalindex], AL_LOOPING,  0                     );

    if (AL_NO_ERROR != alGetError()) {

        err_msg("(%s) ERROR - Failed to set Source properties",prog);

        return -7;

    alGetError();  /* clear any AL errors beforehand */

    /*returns the index of the source you just loaded, increments it and exits*/

    return globalindex++;

}

void openal_playsound (uint32_t index) {

    openal_playsound_loop (index, 0);

}

void openal_pausesound (uint32_t index) {

    if (openalReady == AL_TRUE && index < globalsize)

        alSourcePause(Sources[index]);

}

void openal_stopsound (uint32_t index) {

    openal_stopsound_free(index, 0);

}

void openal_freesound (uint32_t index){

   if (openalReady == AL_TRUE && index < globalsize)

        alSourceStop(Sources[index]);

       // STUB

}

void openal_playsound_loop (unsigned int index, char loops) {

if (openalReady == AL_TRUE && index < globalsize) {

        alSourcePlay(Sources[index]);

    if (loops != 0)

            openal_toggleloop(index);

}

void openal_stopsound_free    (unsigned int index, char freesource) {

    if (openalReady == AL_TRUE && index < globalsize) {

        alSourceStop(Sources[index]);

    if (freesource != 0)

        openal_freesound(index);

}

void openal_toggleloop (uint32_t index) {

    ALint loop;

    if (openalReady == AL_TRUE && index < globalsize) {

        alGetSourcei (Sources[index], AL_LOOPING, &loop);

        alSourcei (Sources[index], AL_LOOPING, !((uint8_t) loop) & 0x00000001);

    }

}

void openal_setvolume (uint32_t index, float gain) {

    if (openalReady == AL_TRUE && index < globalsize)

        alSourcef (Sources[index], AL_GAIN, gain);

}

void openal_setglobalvolume (float gain) {

    if (openalReady == AL_TRUE)

        alListenerf (AL_GAIN, gain);

}

void openal_togglemute () {

    ALfloat gain;

    if (openalReady == AL_TRUE) {

        alGetListenerf (AL_GAIN, &gain);

        if (gain > 0) {

    old_gain = gain;

            gain = 0;

    } else

            gain = old_gain;

    alListenerf (AL_GAIN, gain);

}

}

// Fade in or out by calling a helper thread

void openal_fade (uint32_t index, uint16_t quantity, al_fade_t direction) {

    pthread_t thread;

    HANDLE Thread;

    fade_t *fade;

    if (openalReady == AL_TRUE && index < globalsize) {

        fade = (fade_t*) Malloc(sizeof(fade_t));

        fade->index = index;

        fade->quantity = quantity;

        fade->type = direction;

        pthread_create(&thread, NULL, (void *)helper_fade, (void *)fade);

        pthread_detach(thread);

        Thread = (HANDLE) _beginthread((void *)helper_fade, 0, (void *)fade);

}

void openal_fadein (uint32_t index, uint16_t quantity) {

    openal_fade(index, quantity, AL_FADE_IN);

}

void openal_fadeout (uint32_t index, uint16_t quantity) {

    openal_fade(index, quantity, AL_FADE_OUT);

void openal_setposition (uint32_t index, float x, float y, float z) {

    if (openalReady == AL_TRUE && index < globalsize)

        alSource3f(Sources[index], AL_POSITION, x, y, z);;

}