#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <signal.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <time.h>

static void signal_handler(int _signal);
static int quit_app = 0;

int main(int argc, char *argv[])
{
	signal(SIGINT, signal_handler);

	if (argc <= 3)
		exit(1);	

	int in_fd = open(argv[1], O_RDONLY);
	int out_fd = open(argv[2], O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
	int tsi_fd = open(argv[3], O_RDWR);

	int rlen = 0;
	int wlen = 0;
	int rtsilen = 0;
	int wtsilen = 0;

	int BUFFY = 188 * 20;
	unsigned char buf[BUFFY];
	struct timespec sl[1];
	sl[0].tv_nsec = 250000;
	
	while (!quit_app)
	{
		// read from input (DVR or other)
		rlen = read(in_fd, buf, BUFFY);
		if (rlen > 0)
		{
			// write data to caio device
			wlen = write(tsi_fd, buf, rlen);
			if (wlen != rlen)
			{
				perror("Did not write same amount of data from input to caio!!!");
				exit(1);
			}/* else
				printf("written %d bytes in tsi\n", wlen);
	*/	}

		if (rlen < BUFFY)
		{
			nanosleep(sl, NULL);
		}

		if (rlen < 188)
			continue;


		// read data from caio device - should be decrypted
		// finding sync byte
		do {
			rtsilen = read(tsi_fd, buf, 1);
		//	printf("reading one byte: %02x from tsi\n", buf[0]);
			if (rtsilen && (buf[0] == 0x47)) {
				do {
					int i = read(tsi_fd, buf + rtsilen, 188 - rtsilen);
					rtsilen += i;
		//			printf("reading %d bytes from tsi\n", i);
				} while (rtsilen < 188);

				break;
			}
		} while (1);

//printf("sync byte found: %02x \n", buf[0]);

		wtsilen = 0;
		do {
//			printf("from tsi out: %x %x %x \n", buf[0], buf[1], buf[2]);
			if (buf[0] == 0x47 && buf[1] == 0x1F && buf[2] == 0xFF) {
				// DVB null packet, discard
			} else {
				// write packet to output
				wtsilen += write(out_fd, buf, 188);
			}

			if (rlen == wtsilen)
				break;

			rtsilen = 0;
			do {
				rtsilen += read(tsi_fd, buf + rtsilen, 188 - rtsilen);
			} while (rtsilen < 188);
		} while (1);
	}

	close(in_fd);
	close(out_fd);
	close(tsi_fd);

	exit(0);
}


static void signal_handler(int _signal)
{
	if (!quit_app)
	{
		quit_app = 1;
	}
}