#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static int ugen_ep1, ugen_ep3;

#ifndef UGEN
#define UGEN	"ugen0"
#endif

int
main(int argc, char *argv[])
{
	int chan, freq, i;
	uint8_t cmd[10], rpkt[188], wpkt[188];

	if (argc != 2)
		return -1;

	chan = strtoul(argv[1], NULL, 10);

	if (chan < 13 || chan > 62)
		return -1;

	if ((ugen_ep1 = open("/dev/" UGEN ".01", O_RDWR, 0)) == -1)
		return -1;

	if ((ugen_ep3 = open("/dev/" UGEN ".03", O_RDONLY, 0)) == -1)
		return -1;

	memset(cmd, 0, sizeof(cmd));

	cmd[0] = 0x21;
	write(ugen_ep1, cmd, sizeof(cmd));

	cmd[0] = 0x9f;
	write(ugen_ep1, cmd, sizeof(cmd));
	read(ugen_ep1, rpkt, 3);
	fprintf(stderr, "version: %d.%d.%d\n", rpkt[0], rpkt[1], rpkt[2]);

	cmd[0] = 0x43;
	write(ugen_ep1, cmd, sizeof(cmd));
	read(ugen_ep1, rpkt, 4);
	fprintf(stderr, "serial: %02x%02x%02x%02x\n", rpkt[0], rpkt[1],
	    rpkt[2], rpkt[3]);

	cmd[0] = 0x10;
	cmd[1] = 0x04;
	cmd[2] = 0x00;

	freq = 473143 + (chan - 13) * 6000;

	cmd[3] = (freq >> 16) & 0xff;
	cmd[4] = (freq >> 8) & 0xff;
	cmd[5] = freq & 0xff;
	write(ugen_ep1, cmd, sizeof(cmd));

	memset(cmd, 0, sizeof(cmd));

	cmd[0] = 0x11;
	do {
		write(ugen_ep1, cmd, sizeof(cmd));
		read(ugen_ep1, rpkt, 1);
		fprintf(stderr, ".", rpkt[0]);
	} while (rpkt[0] != 1);
	fprintf(stderr, "o\n");

	cmd[0] = 0x20;
	write(ugen_ep1, cmd, sizeof(cmd));

	for (;;) {
		read(ugen_ep3, rpkt, sizeof(rpkt));

		if (((rpkt[1] ^ 0xb5) & 0x80) == 0x80) {
			fprintf(stderr, "x");
			continue;
		}

		wpkt[0] = 0x47;
		for (i = 1; i < 188; i++)
			wpkt[i] = rpkt[i] ^ 0xb5;

		write(1, wpkt, sizeof(wpkt));

		if ((wpkt[1] & 0x1f) == 0 && wpkt[2] == 0x14) {
			i = 5;
			while (wpkt[i] != 0x73 && wpkt[i] != 0xff && i < 181) {
				i += ((wpkt[i + 1] & 0xf) << 8) | wpkt[i + 2];
			}
			if (wpkt[i] == 0x73) {
				i += 3;
				fprintf(stderr, "%d %02x:%02x:%02x\n",
				    wpkt[i] << 8 | wpkt[i + 1],
				    wpkt[i + 2], wpkt[i + 3], wpkt[i + 4]);
			}
		}
	}

	cmd[0] = 0x21;
	write(ugen_ep1, cmd, sizeof(cmd));

	close(ugen_ep3);
	close(ugen_ep1);

	return 0;
}