using Plugin.Geolocator;

using Plugin.Geolocator.Abstractions;

using System;

​

public static class CommonExtensions

{

    public static double ToRadian(this double value)

    {

        return (Math.PI / 180) * value;

    }

}

​

public struct GeoCoordinates : ICloneable

    {

        public double Longitude;

        public double Latitude;

​

        public bool IsEmpty { get { return Longitude.Equals(0) && Latitude.Equals(0); } }

​

        public string Text { get { return ToString(); } }

​

        public object Clone()

        {

            return new GeoCoordinates()

            {

                Latitude = Latitude,

                Longitude = Longitude

            };

        }

​

        public new string ToString()

        {

            return Latitude + "," + Longitude;

        }

    }

​

public class Program

{

    public static void Main()

    {

        GeoCoordinates login = new GeoCoordinates() {

            Latitude = 40.7598268,

            Longitude = -73.937688833

        };

        GeoCoordinates login2 = new GeoCoordinates() {

            Latitude = 33.00909,

            Longitude = -96.35937

        };

        GeoCoordinates site = new GeoCoordinates() {

            Latitude =  40.775928,

            Longitude = -73.9060499

        };

        double result = GetDistanceInMiles(site,login);

        double resultEAPI = GetDistanceInMilesEAPI(site,login);

        Console.Write("Mobile: " + result);

        Console.WriteLine();

        Console.Write("EAPI: " + resultEAPI);

    }

    public static double GetDistanceInMilesEAPI(GeoCoordinates geoCoordinatesX, GeoCoordinates geoCoordinatesY) {

        Double aSq = Math.Pow(geoCoordinatesX.Latitude - geoCoordinatesY.Latitude, 2);

        Double bSq = Math.Pow(geoCoordinatesX.Longitude - geoCoordinatesY.Longitude, 2);

        Double cSq = aSq + bSq;

        Double milesBetween = Math.Sqrt(cSq) * 69.2;

        return milesBetween;

    }

​

    public static double GetDistanceInMiles(GeoCoordinates geoCoordinatesX, GeoCoordinates geoCoordinatesY)

        {

            double deltaLatitude = (geoCoordinatesY.Latitude - geoCoordinatesX.Latitude).ToRadian();

            double deltaLongitude = (geoCoordinatesY.Longitude - geoCoordinatesX.Longitude).ToRadian();

            double a =

                Math.Sin(deltaLatitude / 2) *

                Math.Sin(deltaLatitude / 2) +

                Math.Cos(geoCoordinatesX.Latitude.ToRadian()) *

                Math.Cos(geoCoordinatesY.Latitude.ToRadian()) *

                Math.Sin(deltaLongitude / 2) *

                Math.Sin(deltaLongitude / 2);

            return 3960 * (2 * Math.Asin(Math.Min(1, Math.Sqrt(a))));

        }

}