export type Coordinates = [number, number];

export const calculateHaversineDistance = (
  [lat1, lon1]: Coordinates,
  [lat2, lon2]: Coordinates
): number => {
  const R = 6371; // Radius of the Earth in kilometers

  const dLat = degreesToRadians(lat2 - lat1);
  const dLon = degreesToRadians(lon2 - lon1);

  const a =
    Math.sin(dLat / 2) * Math.sin(dLat / 2) +
    Math.cos(degreesToRadians(lat1)) *
      Math.cos(degreesToRadians(lat2)) *
      Math.sin(dLon / 2) *
      Math.sin(dLon / 2);

  const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
  const distance = R * c; // Distance in kilometers
  return distance;
};

const degreesToRadians = (degrees: number): number => degrees * (Math.PI / 180);