#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <math.h>

#include <laaga/laaga.h>

#define TABLE_SIZE 4096
#define FREQ 440.0f

laaga_port_t *sin_output_port;
unsigned int sample_rate;
unsigned int phase = 0;
unsigned int inc = 0;
sample_t sin_tbl[TABLE_SIZE];

int process (nframes_t nframes, void *arg)
{
	sample_t *out = (sample_t *) laaga_port_get_buffer(sin_output_port, nframes);
	unsigned int i;

	for(i=0; i<nframes; i++) {
		out[i] = sin_tbl[phase];
		phase += inc;
		phase &= TABLE_SIZE - 1;
	}

	return 0;      
}

int srate (nframes_t nframes, void *arg)
{
	printf ("the sample rate is now %lu/sec\n", nframes);
	sample_rate = nframes;
	inc = FREQ * TABLE_SIZE / sample_rate;
	return 0;
}

int main (int argc, char *argv[])
{
	laaga_client_t *client;
	unsigned int i;

	if ((client = laaga_client_new("sin_client")) == 0) {
		fprintf (stderr, "laaga server not running?\n");
		return 1;
	}

	/* Create wavetable */
	for (i=0; i<TABLE_SIZE; i++) {
		sin_tbl[i] = sin((float)i / (float)TABLE_SIZE * 2.0f * M_PI);
	}

	laaga_set_process_callback (client, process, 0);
	laaga_set_sample_rate_callback (client, srate, 0);

	sample_rate = laaga_get_sample_rate(client);
	inc = FREQ * TABLE_SIZE / sample_rate;
	printf ("engine sample rate: %u\n", sample_rate);

	sin_output_port = laaga_port_register (client, "sin_wave", LAAGA_DEFAULT_AUDIO_TYPE, LaagaPortIsOutput, 0);

	if (laaga_activate(client)) {
		fprintf (stderr, "cannot activate client\n");
		exit(1);
	}

	printf("client activated\n");

	if (laaga_port_connect (client, sin_output_port->shared->name, "ALSA I/O:Output 1")) {
		fprintf (stderr, "cannot connect output ports\n");
	} 

	sleep (5);

	printf ("done sleeping, now closing...\n");
	laaga_client_close (client);
	exit (0);
}