/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  Sam Lantinga

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Library General Public

    License as published by the Free Software Foundation; either

    version 2 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

    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public

    License along with this library; if not, write to the Free

    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga

    slouken@libsdl.org

*/

#include <stdlib.h>

#include <stdio.h>

#include <string.h>

#include <errno.h>

#include <unistd.h>

#include <fcntl.h>

#include <signal.h>

#include <sys/types.h>

#include <sys/time.h>

#include <sched.h>

#include <sys/asoundlib.h>

#include "SDL_audio.h"

#include "SDL_error.h"

#include "SDL_audiomem.h"

#include "SDL_audio_c.h"

#include "SDL_timer.h"

#include "SDL_nto_audio.h"

/* The tag name used by NTO audio */

#define DRIVER_NAME         "nto"

/* default channel communication parameters */

#define DEFAULT_CPARAMS_RATE 22050

#define DEFAULT_CPARAMS_VOICES 1

#define DEFAULT_CPARAMS_FRAGS_MIN 1

#define DEFAULT_CPARAMS_FRAGS_MAX 1

/* Open the audio device for playback, and don't block if busy */

/* Audio driver functions */

static int NTO_OpenAudio(_THIS, SDL_AudioSpec *spec);

static void NTO_WaitAudio(_THIS);

static void NTO_PlayAudio(_THIS);

static Uint8 *NTO_GetAudioBuf(_THIS);

static void NTO_CloseAudio(_THIS);

static snd_pcm_channel_status_t cstatus;

/* PCM transfer channel parameters initialize function */

static void init_pcm_cparams(snd_pcm_channel_params_t* cparams)

{

	memset(cparams,0,sizeof(snd_pcm_channel_params_t));

	cparams->channel = SND_PCM_CHANNEL_PLAYBACK;

	cparams->mode = SND_PCM_MODE_BLOCK;

	cparams->stop_mode  = SND_PCM_STOP_STOP;

	cparams->format.format = SND_PCM_SFMT_S16_LE;

	cparams->format.interleave = 1;

	cparams->format.rate = DEFAULT_CPARAMS_RATE;

	cparams->format.voices = DEFAULT_CPARAMS_VOICES;

	cparams->buf.block.frag_size = DEFAULT_CPARAMS_FRAG_SIZE;

	cparams->buf.block.frags_min = DEFAULT_CPARAMS_FRAGS_MIN;

	cparams->buf.block.frags_max = DEFAULT_CPARAMS_FRAGS_MAX;

}

	int available;

	int rval;

	snd_pcm_t *handle;

	available = 0;

	handle = NULL;

			available = 0;

	}

	}

	fprintf(stderr,"AudioAvailable rtns %d\n", available);

	return(available);

}

static void Audio_DeleteDevice(SDL_AudioDevice *device)

{

	fprintf(stderr,"Audio_DeleteDevice\n");

	free(device->hidden);

	free(device);

}

static SDL_AudioDevice *Audio_CreateDevice(int devindex)

{

	SDL_AudioDevice *this;

	fprintf(stderr,"Audio_CreateDevice\n");

	/* Initialize all variables that we clean on shutdown */

	this = (SDL_AudioDevice *)malloc(sizeof(SDL_AudioDevice));

	if ( this ) {

		memset(this, 0, (sizeof *this));

		this->hidden = (struct SDL_PrivateAudioData *)

	}

	if ( (this == NULL) || (this->hidden == NULL) ) {

		SDL_OutOfMemory();

		if ( this ) {

			free(this);

		}

		return(0);

	}

	memset(this->hidden, 0, (sizeof *this->hidden));

	audio_handle = NULL;

	/* Set the function pointers */

	this->OpenAudio = NTO_OpenAudio;

	this->WaitAudio = NTO_WaitAudio;

	this->PlayAudio = NTO_PlayAudio;

	this->GetAudioBuf = NTO_GetAudioBuf;

	this->CloseAudio = NTO_CloseAudio;

	this->free = Audio_DeleteDevice;

	return this;

}

/* Don't change the name from "ALSA_bootstrap" - that's how it's called */

AudioBootStrap ALSA_bootstrap = {

	DRIVER_NAME, "Neutrino PCM audio",

	Audio_Available, Audio_CreateDevice

};

/* This function waits until it is possible to write a full sound buffer */

static void NTO_WaitAudio(_THIS)

{

	{

}

static void NTO_PlayAudio(_THIS)

{

	towrite = pcm_len;

		written = snd_pcm_plugin_write(audio_handle, pcm_buf, towrite);

		fprintf(stderr, "NTO_PlayAudio: written = %d towrite = %d\n",written,towrite);

				fprintf(stderr, "errno == EAGAIN written %d\n", written);

				towrite -= written; //we wrote some data

				continue;

					fprintf(stderr, "snd_pcm_plugin_status failed %s\n",snd_strerror(rval));

					fprintf(stderr, "buffer underrun\n");

						fprintf(stderr, "NTO_PlayAudio: prepare failed %s\n",snd_strerror(rval));

						SDL_SetError("snd_pcm_plugin_prepare failed: %s\n",snd_strerror(rval) );

						return;

					}

				}		        		

 				continue;

			}

				return;

			}

		}

		else

		{

			towrite -= written; //we wrote all remaining data

		}

	return;

}

static Uint8 *NTO_GetAudioBuf(_THIS)

{

	return(pcm_buf);

}

static void NTO_CloseAudio(_THIS)

{

	int rval;

	if ( audio_handle != NULL ) {

			return;

		}

			SDL_SetError("snd_pcm_close failed: %s\n",snd_strerror(rval));

			return;

		}

		audio_handle = NULL;

	}

}

static int NTO_OpenAudio(_THIS, SDL_AudioSpec *spec)

{

	int rval;

	int format;

	Uint16 test_format;

	int twidth;

	int found;

	audio_handle = NULL;

	if ( pcm_buf != NULL ) {

		free((Uint8 *)pcm_buf); 

		pcm_buf = NULL;

	}

	/* initialize channel transfer parameters to default */

	init_pcm_cparams(&cparams);

	/* Open the audio device */

	if ( rval < 0 ) {

		SDL_SetError("snd_pcm_open failed: %s\n", snd_strerror(rval));

		return(-1);

	}

	/* Try for a closest match on audio format */

	format = 0;

	for ( test_format = SDL_FirstAudioFormat(spec->format);	!found ; ) 

	{

		fprintf(stderr, "Trying format 0x%4.4x spec->samples %d\n", test_format,spec->samples);

			case AUDIO_U8:

				format = SND_PCM_SFMT_U8;

				found = 1;

				break;

			case AUDIO_S8:

				format = SND_PCM_SFMT_S8;

				found = 1;

				break;

			case AUDIO_S16LSB:

				format = SND_PCM_SFMT_S16_LE;

				found = 1;

				break;

			case AUDIO_S16MSB:

				format = SND_PCM_SFMT_S16_BE;

				found = 1;

				break;

			case AUDIO_U16LSB:

				format = SND_PCM_SFMT_U16_LE;

				found = 1;

				break;

			case AUDIO_U16MSB:

				format = SND_PCM_SFMT_U16_BE;

				found = 1;

				break;

			default:

				break;

		}

		if ( ! found ) {

			test_format = SDL_NextAudioFormat();

		}

	}

	/* assumes test_format not 0 on success */

	if ( test_format == 0 ) {

		SDL_SetError("Couldn't find any hardware audio formats");

		return(-1);

	}

	spec->format = test_format;

	/* Set the audio format */

	cparams.format.format = format;

	/* Set mono or stereo audio (currently only two channels supported) */

	cparams.format.voices = spec->channels;

	fprintf(stderr,"intializing channels %d\n", cparams.format.voices);

	/* Set rate */

	cparams.format.rate = spec->freq ;

	/* Setup the transfer parameters according to cparams */

	rval = snd_pcm_plugin_params(audio_handle, &cparams);

	if (rval < 0) {

		SDL_SetError("snd_pcm_channel_params failed: %s\n", snd_strerror (rval));

		return(-1);

	}

		fprintf(stderr,"real max frags : %d\n", csetup.buf.block.frags_max );

	/* Trigger audio playback */

	rval = snd_pcm_plugin_prepare( audio_handle, SND_PCM_CHANNEL_PLAYBACK);

	if (rval < 0) {

	}

	/* Get the parent process id (we're the parent of the audio thread) */

	parent = getpid();

	/* We're ready to rock and roll. :-) */

	return(0);

}