/* See LICENSE file for copyright and license details. */
#include "common.h"


static int
parse(char *s, struct location *location)
{
	errno = 0;

	location->latitude = strtod(s, &s);
	if (errno)
		return -1;

	while (isspace(*s))
		s++;
	if (*s == ',' || *s == ':')
		s++;
	while (isspace(*s))
		s++;

	location->longitude = strtod(s, &s);
	if (errno)
		return -1;

	while (isspace(*s) && *s != '\n')
		s++;

	return (*s && *s != '\n') ? -1 : 0;
}


int
libgeome_get_from_file(struct libgeome_context *ctx, struct libgeome_data *out, const char *path)
{
	struct location location;
	FILE *f;
	char *line = NULL;
	size_t size = 0;
	int r;

	if (!path)
		path = libgeome_default_geolocation_file;

	f = fopen(path, "r");
	if (!f) {
		if (errno == ENOENT)
			ctx->print_debug(ctx, "fopen %s r: %s\n", path, strerror(errno));
		else
			ctx->print_error(ctx, "fopen %s r: %s\n", path, strerror(errno));
		return 1;
	}

again:
	if (getline(&line, &size, f) < 0) {
		if (feof(f)) {
			ctx->print_debug(ctx, "%s is empty\n", path, strerror(errno));
		} else {
			if (errno == EINTR) {
				clearerr(f);
				goto again;
			}
			ctx->print_error(ctx, "getline %s: %s\n", path, strerror(errno));
		}
		fclose(f);
		free(line);
		return 1;
	}

	fclose(f);

	r = parse(line, &location);
	free(line);
	if (!r) {
		if (!isfinite(location.latitude) || !isfinite(location.longitude))
			r = -1;
		else if (location.latitude < -90 || location.latitude > 90)
			r = -1;
		else if (location.longitude < -180 || location.longitude > 180)
			r = -1;
	}
	if (r) {
		ctx->print_debug(ctx, "the first line of %s was not a coordinate pair\n", path, strerror(errno));
		return 1;
	}

	out->requested_data &= LIBGEOME_DATUM_LATITUDE | LIBGEOME_DATUM_LONGITUDE;
	if (out->requested_data) {
		if (out->requested_data & LIBGEOME_DATUM_LATITUDE)
			out->latitude = location.latitude;
		if (out->requested_data & LIBGEOME_DATUM_LONGITUDE)
			out->longitude = location.longitude;
	}

	return 0;
}