#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
#include <termios.h>
#include <unistd.h>

int z__b_stream_is_tty(FILE *fp)
{
	return isatty(fileno(fp));
}

int z__b_stream_dimensions(FILE *fp, unsigned int *w, unsigned int *h)
{
	if (!isatty(fileno(fp))) {
		return -1;
	}

	struct winsize ws;
	if (ioctl(fileno(fp), TIOCGWINSZ, &ws) == -1) {
		return -1;
	}

	if (w) {
		*w = ws.ws_col;
	}

	if (h) {
		*h = ws.ws_row;
	}

	return 0;
}

int z__b_stream_cursorpos(FILE *in, FILE *out, unsigned int *x, unsigned int *y)
{
	if (!isatty(fileno(in)) || !isatty(fileno(out))) {
		return -1;
	}

	struct termios term, restore;

	tcgetattr(fileno(in), &term);
	tcgetattr(fileno(in), &restore);
	term.c_lflag &= ~(ICANON | ECHO);
	tcsetattr(fileno(in), TCSANOW, &term);

	const char *cmd = "\033[6n";
	write(fileno(out), cmd, strlen(cmd));

	char buf[64];
	read(fileno(in), buf, sizeof buf);

	tcsetattr(fileno(in), TCSANOW, &restore);

	unsigned int row, col;
	int r = sscanf(buf, "\033[%u;%uR", &row, &col);
	if (r != 2) {
		return -1;
	}

	*x = col - 1;
	*y = row - 1;

	return 0;
}