/*
   audio/buffers.h
   This file is part of the Osirion project and is distributed under
   the terms of the GNU General Public License version 2
*/

#include <string.h>

#include "audio/buffers.h"
#include "audio/pcm.h"
#include "audio/wav.h"
#include "sys/sys.h"

namespace audio {

std::map<std::string, size_t> Buffers::registry;
size_t Buffers::index;
ALuint Buffers::buffers[MAXBUFFERS];

void Buffers::init()
{
	clear();	
		
	alGenBuffers(MAXBUFFERS, buffers);

	int error;
	if ((error = alGetError()) != AL_NO_ERROR) {
		con_warn << "Error " << error << " initializing OpenAL buffers!" << std::endl;
		return;
	}
}

void Buffers::shutdown()
{
	alDeleteBuffers(MAXBUFFERS, buffers);
	
	int error;
	if ((error = alGetError()) != AL_NO_ERROR) {
		con_warn << "Error " << error << " clearing OpenAL buffers!" << std::endl;
		return;
	}
	
	clear();
}

void Buffers::clear()
{
	registry.clear();
	memset(buffers,0, sizeof(buffers));
	index = 0;
}


size_t Buffers::load(std::string name)
{
	// check if it is already loaded
	iterator it = registry.find(name);
	if (it != registry.end())
		return (*it).second;

	// load wav file
	PCM *pcm = Wav::load(name);
	if (!pcm) {
		registry[name] = 0;
		return 0;
	}	

	if (index == MAXBUFFERS) {
		con_error << "Buffer limit " << MAXBUFFERS << " exceeded!" << std::endl;
		delete pcm;
		registry[name] = 0;
		return 0;
	}
	
	ALenum format = 0;
	if (pcm->bitspersample() == 16) {
		if (pcm->channels() == 1) {
			format = AL_FORMAT_MONO16;
		} else if (pcm->channels() == 2) {
			format = AL_FORMAT_STEREO16;
		};
	} else if (pcm->bitspersample() == 8) {
		if (pcm->channels() == 1) {
			format = AL_FORMAT_MONO8;
		} else if (pcm->channels() == 2) {
			format = AL_FORMAT_STEREO8;
		};
	}
	
	size_t id = index;
	alBufferData(buffers[id], format, pcm->data(), pcm->size(), pcm->samplerate());
	if (alGetError()!= AL_NO_ERROR) {
		con_warn << "Error loading PCM data " << name << std::endl;
	}

	registry[name] = id;
	index++;

	delete pcm;

	return id;
}

size_t Buffers::find(std::string name)
{
	size_t id = 0;
	iterator it = registry.find(name);
	if (it != registry.end())
		id = (*it).second;
	return id;
}

void Buffers::bind(ALuint source, size_t id)
{
	int error;
	alSourcei(source, AL_BUFFER, buffers[id]);
	if ((error = alGetError()) != AL_NO_ERROR) {
		con_warn << "Error " << error << " binding  buffer " << buffers[id] << " to source " << source << std::endl;
	}
}

void Buffers::bind(ALuint source, std::string name)
{
	bind(source, find(name));
}

}