Using WinRT libraries from a Windows Desktop application: Setting the LockScreen image

Program.cs

namespace WinRTTest
{
    using System;
    using System.Collections.Generic;
    using System.IO;
    using System.Linq;
    using System.Net.Http;
    using System.Threading.Tasks;
    using Windows.Storage;
    using Windows.System.UserProfile;

    class Program
    {
        const string urlFormat = "http://www.bing.com{0}_{1}x{2}{3}";

        static void Main(string[] args)
        {
            Console.WriteLine("Fetching latest Bing Daily Picture...");
            UpdateAsync().GetAwaiter().GetResult();
            Console.WriteLine("Done.");
        }

        static async Task UpdateAsync()
        {
            using (var client = new HttpClient())
            using (HttpResponseMessage response = await client.GetAsync("http://www.bing.com/HPImageArchive.aspx?format=js&n=1"))
            {
                BingImageArchive model = await response.Content.ReadAsAsync<BingImageArchive>();
                BingImage image = model.Images.Single();

                const int width = 1920;
                const int height = 1080;
                string url = string.Format(urlFormat, image.UrlBase, width, height, Path.GetExtension(image.Url));

                using (Stream stream = await client.GetStreamAsync(url))
                {
                    var file = await KnownFolders.PicturesLibrary.CreateFileAsync("LockScreen" + Path.GetExtension(image.Url), CreationCollisionOption.ReplaceExisting);

                    using (var fileStream = await file.OpenStreamForWriteAsync())
                    {
                        await stream.CopyToAsync(fileStream);
                    }

                    await LockScreen.SetImageFileAsync(file);
                }
            }
        }
    }

    class BingImageArchive
    {
        public ICollection<BingImage> Images { get; set; }
    }

    class BingImage
    {
        public string Url { get; set; }
        public string UrlBase { get; set; }
    }
}