using System.Threading.Tasks;

using System.Collections.Generic;

using System;

​

public interface IWeatherProvider

    {

        //calling an external service

        Task<int> GetTemperatureAsync(string longitude, string latitude);

        //calling an external service

        Task<int> GetHumidityAsync(string longitude, string latitude);

​

        Task<IDictionary<string, WeatherForecast>> GetWeatherForecastAsync(IEnumerable<string> source);

    }

    public class WeatherForecast

    {

        public int Temperature { get; set; }

        public int Humidity { get; set; }

    }

​

    public class WeatherProvider : IWeatherProvider

    {

        public Task<int> GetTemperatureAsync(string longitude, string latitude) => throw new NotImplementedException();

​

        public Task<int> GetHumidityAsync(string longitude, string latitude) => throw new NotImplementedException();

        public async Task<IDictionary<string, WeatherForecast>> GetWeatherForecastAsync(IEnumerable<string> coordinates)

        {

        }

    }

​

    public class Client

    {

        private readonly IWeatherProvider _weatherProvider;

​

        public Client(IWeatherProvider weatherProvider)

        {

            _weatherProvider = weatherProvider;

        }

​

        public void GetWeatherForecast()

        {

            var source = new string[] { "14.408080, 18.887114", "21.427503, 47.382691", "21.099875, 79.748037"};

​

            _weatherProvider.GetWeatherForecastAsync(source);

        }

    }