/*
 *
 * ao_example.c
 *
 *     Written by Stan Seibert - July 2001
 *
 * Legal Terms:
 *
 *     This source file is released into the public domain.  It is
 *     distributed without any warranty; without even the implied
 *     warranty * of merchantability or fitness for a particular
 *     purpose.
 *
 * Function:
 *
 *     This program opens the default driver and plays a 440 Hz tone for
 *     one second.
 *
 * Compilation command line (for Linux systems):
 *
 *     gcc -o ao_example ao_example.c -lao -ldl -lm -lpthread
 *
 */

#include <stdio.h>
#include <string.h>
#include <ao/ao.h>
#include <math.h>
#include <pthread.h>

#define BUF_SIZE 4096

/* struct to hpold info for second thread */
struct pass_ptr {
	ao_device *device2;
	ao_sample_format format2;
};

/* function called by second thread */
void *play2(void *play_ptr)
{
	char *buffer2;
	int buf_size2;
	int sample2;
	float freq2 = 120.0;
	int i2;
	
	struct pass_ptr *play = (struct pass_ptr*) play_ptr;
	
	/* -- Fill buffer -- */
	buf_size2 = play->format2.bits/8 * play->format2.channels * play->format2.rate;
	buffer2 = calloc(buf_size2,
			sizeof(char));

	for (i2 = 0; i2 < play->format2.rate; i2++) {
		sample2 = (int)(0.75 * 32768.0 *
			sin(2 * M_PI * freq2 * ((float) i2/play->format2.rate)));

		/* Put the same stuff in left and right channel */
		buffer2[4*i2] = buffer2[4*i2+2] = sample2 & 0xff;
		buffer2[4*i2+1] = buffer2[4*i2+3] = (sample2 >> 8) & 0xff;
	}
	/* play from second thread */
	ao_play(play->device2, buffer2, buf_size2);

}

int main(int argc, char **argv)
{
	ao_device *device;
	ao_sample_format format;
	int default_driver;
	char *buffer;
	int buf_size;
	int sample;
	float freq = 360.0;
	int i;
	int default_driver2;
	pthread_t play2_thread;
	struct pass_ptr play_ptr;
	

	/* -- Initialize -- */

	fprintf(stderr, "libao example program\n");

	ao_initialize();

	/* -- Setup for default driver -- */

	default_driver = ao_default_driver_id();

    memset(&format, 0, sizeof(format));
	format.bits = 16;
	format.channels = 2;
	format.rate = 44100;
	format.byte_format = AO_FMT_LITTLE;

	/* -- Open first device -- */
	device = ao_open_live(default_driver, &format, NULL /* no options */);
	if (device == NULL) {
		fprintf(stderr, "Error opening device.\n");
		return 1;
	}

    memset(&play_ptr.format2, 0, sizeof(play_ptr.format2));
	play_ptr.format2.bits = 16;
	play_ptr.format2.channels = 2;
	play_ptr.format2.rate = 44100;
	play_ptr.format2.byte_format = AO_FMT_LITTLE;

	/* -- Open second device -- */
	play_ptr.device2 = ao_open_live(default_driver, &play_ptr.format2, NULL /* no options */);
	if (play_ptr.device2 == NULL) {
		fprintf(stderr, "Error opening device2.\n");
		return 1;
	}
	
	/* create second thread to play, pass struct pointer with device and format info */
	if(pthread_create(&play2_thread, NULL, play2, &play_ptr)) {

		fprintf(stderr, "Error creating thread\n");
	return 1;

	}
	
	/* -- Fill buffer with stuff -- */
	buf_size = format.bits/8 * format.channels * format.rate;
	buffer = calloc(buf_size,
			sizeof(char));

	for (i = 0; i < format.rate; i++) {
		sample = (int)(0.75 * 32768.0 *
			sin(2 * M_PI * freq * ((float) i/format.rate)));

		/* Put the same stuff in left and right channel */
		buffer[4*i] = buffer[4*i+2] = sample & 0xff;
		buffer[4*i+1] = buffer[4*i+3] = (sample >> 8) & 0xff;
	}
	
	/* play in main thread */
	ao_play(device, buffer, buf_size);

	/* wait for the second thread to finish */
	if(pthread_join(play2_thread, NULL)) {
		fprintf(stderr, "Error joining thread\n");
	return 2;
	}

	/* -- Close and shutdown -- */
	ao_close(device);
	ao_close(play_ptr.device2);

	ao_shutdown();

  return (0);
}