/*

 * 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 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 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 "openalwrap.h"

#ifdef __CPLUSPLUS

extern "C" {

#endif 

	// Sources are points emitting sound.

	ALuint *Sources;

	// Buffers hold sound data.

	ALuint *Buffers;

	//index for Sources and Buffers

	ALuint globalindex, globalsize;

	// Position of the source sound.

	ALfloat **SourcePos;

	// Velocity of the source sound.

	ALfloat **SourceVel;

	ALint openal_close(void) {

		/* This function stops all the sounds, deallocates all memory and closes OpenAL */

		int i;

		ALCcontext *context;

		ALCdevice  *device;

		alSourceStopv	(globalsize, Sources);

		alDeleteSources (globalsize, Sources);

		alDeleteBuffers (globalsize, Buffers);

		for (i = 0; i < globalsize; i++) {

			free(SourcePos[i]);

			free(SourceVel[i]);

		}

		free(SourcePos);

		free(SourceVel);

		free(Sources);

		free(Buffers);

		context = alcGetCurrentContext();

		device  = alcGetContextsDevice(context);

		alcMakeContextCurrent(NULL);

		alcDestroyContext(context);

		alcCloseDevice(device);

		return AL_TRUE;

	}

	ALint openal_init(int memorysize) {	

		/* This function initializes an OpenAL contex, allocates memory space for data and prepares OpenAL buffers*/

		ALCcontext *context;

		ALCdevice *device;

		ALenum error;

		const ALCchar *default_device;

		// Position of the listener.

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

		// Velocity of the listener.

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

		// Orientation of the listener. (first 3 elements are "at", second 3 are "up")

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

		default_device = alcGetString(NULL, ALC_DEFAULT_DEVICE_SPECIFIER);

		fprintf(stderr, "Using default device: %s\n", default_device);

		if ((device = alcOpenDevice(default_device)) == NULL) {

			fprintf(stderr, "ERROR %d: Failed to open sound device\n", error);

			return AL_FALSE;

		}

		context = alcCreateContext(device, NULL);

		alcMakeContextCurrent(context);

		alcProcessContext(context);

		if (AlGetError("ERROR %d: Creating a new contex\n") != AL_TRUE)

			return AL_FALSE;

		//allocate memory space for buffers and sources

		globalsize = memorysize;

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

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

		SourcePos = (ALfloat**) Malloc(sizeof(ALfloat*)*globalsize);

		SourceVel = (ALfloat**) Malloc(sizeof(ALfloat*)*globalsize);

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

		alListenerf (AL_GAIN,		 1.0f		);

		alListenerfv(AL_POSITION,    ListenerPos);

		alListenerfv(AL_VELOCITY,    ListenerVel);

		alListenerfv(AL_ORIENTATION, ListenerOri);

		if (AlGetError("ERROR %d: Setting Listener properties\n") != AL_TRUE)

			return AL_FALSE;

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

		return AL_TRUE;

	}

	int openal_loadfile (const char *filename){

		/* This function opens a file, loads into memory and allocates the Source buffer for playing*/

		ALenum format;

		ALsizei bitsize;

		ALsizei freq;

		uint8_t *data;

		uint32_t fileformat;

		int i, error;

		FILE *fp;

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

		fp = Fopen (filename, "rb");

		if (fp == NULL)

			return -1;

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

		fclose (fp);

		if (error < 0) {

			fprintf(stderr, "ERROR: file %s is too short \n", filename);

			return -2;

		}

		//prepare the buffers to receive data

		alGenBuffers(1, &Buffers[globalindex]);

		if (AlGetError("ERROR %d: Allocating memory for buffers\n") != AL_TRUE)

			return -3;

		//prepare the sources to emit sound

		alGenSources(1, &Sources[globalindex]);

		if (AlGetError("ERROR %d: Allocating memory for sources\n") != AL_TRUE)

			return -4;

		if (fileformat == 0x5367674F) //check if ogg

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

		else {

			if (fileformat == 0x46464952) //check if wav

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

			else {

				fprintf(stderr, "ERROR: File format (%08X) not supported!\n", invert_endianness(fileformat));

				return -5;

			}

		}

		//copy pcm data in one buffer

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

		free(data);		//deallocate data to save memory

		if (AlGetError("ERROR %d: Writing data to buffer\n") != AL_TRUE)

			return -5;

		//memory allocation for source position and velocity

		SourcePos[globalindex] = (ALfloat*) Malloc(sizeof(ALfloat)*3);

		SourceVel[globalindex] = (ALfloat*) Malloc(sizeof(ALfloat)*3);

		if (SourcePos[globalindex] == NULL || SourceVel[globalindex] == NULL)

			return -6;

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

		for (i = 0; i < 3; i++) {

			SourcePos[globalindex][i] = 0.0;

			SourceVel[globalindex][i] = 0.1;

		}	

		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[globalindex]);

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

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

		if (AlGetError("ERROR %d: Setting source properties\n") != AL_TRUE)

			return -7;

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

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

		return globalindex++;

	}

	ALint openal_toggleloop (int index){

		/*Set or unset looping mode*/

		ALint loop;

		if (index >= globalsize) {

			fprintf(stderr, "ERROR: index out of bounds (got %d, max %d)", index, globalindex);

			return AL_FALSE;

		}

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

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

		if (AlGetError("ERROR %d: Getting or setting loop property\n") != AL_TRUE)

			return AL_FALSE;

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

		return AL_TRUE;

	}

	ALint openal_setvolume (int index, unsigned char percentage) {

		/*Set volume for sound number index*/

		if (index >= globalindex) {

			fprintf(stderr, "ERROR: index out of bounds (got %d, max %d)", index, globalindex);

			return AL_FALSE;

		}

		if (percentage > 100)

			percentage = 100;

		alSourcef (Sources[index], AL_GAIN, (ALfloat) percentage/100.0f);

		if (AlGetError("ERROR %d: Setting volume for last sound\n") != AL_TRUE)

			return AL_FALSE;

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

		return AL_TRUE;

	}

	ALint openal_setglobalvolume (unsigned char percentage) {

		/*Set volume for all sounds*/		

		if (percentage > 100)

			percentage = 100;

		alListenerf (AL_GAIN, (ALfloat) percentage/100.0f);

		if (AlGetError("ERROR %d: Setting global volume\n") != AL_TRUE)

			return AL_FALSE;

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

		return AL_TRUE;

	}

	ALint openal_togglemute () {

		/*Mute or unmute sound*/

		ALfloat mute;

		alGetListenerf (AL_GAIN, &mute);

		if (mute > 0) 

			mute = 0;

		else

			mute = 1.0;

		alListenerf (AL_GAIN, mute);

		if (AlGetError("ERROR %d: Setting mute property\n") != AL_TRUE)

			return AL_FALSE;

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

		return AL_TRUE;

	}

	ALint openal_fadeout(int index, unsigned int quantity) {

		if (index >= globalindex) {

			fprintf(stderr, "ERROR: index out of bounds (got %d, max %d)", index, globalindex);

			return AL_FALSE;

		}

#endif

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

		return AL_TRUE;

	}

	ALint openal_fadein(int index, unsigned int quantity) {

		if (index >= globalindex) {

			fprintf(stderr, "ERROR: index out of bounds (got %d, max %d)", index, globalindex);

			return AL_FALSE;

		}

#endif

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

		return AL_TRUE;

	}

	ALint openal_playsound(int index){

		/*Play sound number index*/

		if (index >= globalindex) {

			fprintf(stderr, "ERROR: index out of bounds (got %d, max %d)", index, globalindex);

			return AL_FALSE;

		}

		alSourcePlay(Sources[index]);

		if (AlGetError("ERROR %d: Playing last sound\n") != AL_TRUE)

			return AL_FALSE;

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

		return AL_TRUE;

	}

	ALint openal_pausesound(int index){

		/*Pause sound number index*/

		if (index >= globalindex) {

			fprintf(stderr, "ERROR: index out of bounds (got %d, max %d)", index, globalindex);

			return AL_FALSE;

		}

		alSourcePause(Sources[index]);

		if (AlGetError("ERROR %d: Pausing last sound\n") != AL_TRUE)

			return AL_FALSE;

		return AL_TRUE;

	}

	ALint openal_stopsound(int index){

		/*Stop sound number index*/

		if (index >= globalindex) {

			fprintf(stderr, "ERROR: index out of bounds (got %d, max %d)", index, globalindex);

			return AL_FALSE;

		}

		alSourceStop(Sources[index]);

		if (AlGetError("ERROR %d: Stopping last sound\n") != AL_TRUE)

			return AL_FALSE;

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

		return AL_TRUE;

	}

#ifdef __CPLUSPLUS

}

#endif