export type Location = {
	latitude: number;
	longitude: number;
};

/**
 * Returns the distance between src and dst as meters
 */
export const haversineDistance = (src: Location, dst: Location) => {
	const RADIUS_OF_EARTH_IN_KM = 6371;
	const toRadian = (deg: number) => deg * (Math.PI / 180);

	const dLat = toRadian(dst.latitude - src.latitude);
	const dLon = toRadian(dst.longitude - src.longitude);

	const a =
		Math.sin(dLat / 2) * Math.sin(dLat / 2) +
		Math.cos(toRadian(src.latitude)) *
			Math.cos(toRadian(dst.latitude)) *
			Math.sin(dLon / 2) *
			Math.sin(dLon / 2);
	const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
	return RADIUS_OF_EARTH_IN_KM * c * 1000;
};