/* this file is a part of amp software, (C) tomislav uzelac 1996,1997

	Origional code by: Karl Anders Oygard
	Modified by:
	* Andrew Richards - moved code from audio.c

 */

#include "amp.h"
#include <unistd.h>
#include <stdio.h>
#include <dmedia/audio.h>
#include "audioIO.h"

/* declare these static to effectively isolate the audio device */

static ALport audioport;
static ALconfig audioconfig;
static audio_info_t auinfo;


/* audioOpen() */
/* should open the audio device, perform any special initialization		 */
/* Set the frequency, no of channels and volume. Volume is only set if */
/* it is not -1 */


void
audioOpen()
{
	ALconfig audioconfig;
	audioconfig = ALnewconfig();
 
	if (!audioconfig)
		die("out of memory\n");
	else {
		long pvbuf[] = { AL_OUTPUT_COUNT, 0, AL_MONITOR_CTL, 0, AL_OUTPUT_RATE, 0};
		
		if (ALgetparams(AL_DEFAULT_DEVICE, pvbuf, 6) < 0)
			if (oserror() == AL_BAD_DEVICE_ACCESS)
				die("couldn't access audio device\n");
		
		if (pvbuf[1] == 0 && pvbuf[3] == AL_MONITOR_OFF) {
			long al_params[] = { AL_OUTPUT_RATE, 0};
			
			al_params[1] = frequency;
			ALsetparams(AL_DEFAULT_DEVICE, al_params, 2);
		} else
			if (pvbuf[5] != frequency)
				die("audio device is already in use with wrong sample output rate\n");
		
		/* ALsetsampfmt(audioconfig, AL_SAMPFMT_TWOSCOMP); this is the default */
		/* ALsetwidth(audioconfig, AL_SAMPLE_16); this is the default */
		
		if (!stereo) ALsetchannels(audioconfig, AL_MONO);
		/* else ALsetchannels(audioconfig, AL_STEREO); this is the default */
		
		audioport = ALopenport("amp", "w", audioconfig);
		if (audioport == (ALport) 0) {
			switch (oserror()) {
			case AL_BAD_NO_PORTS:
				die("system is out of ports\n");
				
			case AL_BAD_DEVICE_ACCESS:
				die("couldn't access audio device\n");
				
			case AL_BAD_OUT_OF_MEM:
				die("out of memory\n");
			}			 
			exit(-1);
		}
	}
}


/* audioSetVolume - only code this if your system can change the volume while */
/*									playing. sets the output volume 0-100 */

void
audioSetVolume(int volume)
{
}


/* audioClose() */
/* should close the audio device and perform any special shutdown			 */

void
audioClose()
{
	???
	DB(audio, msg("audio: closed %d\n",audio_fd) );
}


/* audioWrite */
/* writes count bytes from buffer to the audio device */
/* returns the number of bytes actually written */

int inline
audioWrite(char *buffer, int count)
{
	ALwritesamps(audioport, au_buf, count / 2);
	return(count); /* can we do better? */
}

/* Let buffer.c have the audio descriptor so it can select on it. This means	*/
/* that the program is dependent on an file descriptor to work. Should really */
/* move the select's etc (with inlines of course) in here so that this is the */
/* ONLY file which has hardware dependent audio stuff in it										*/

int
getAudioFd()
{
	return(audio_fd); ???
}