namespace BingImageOfTheDay
{
    using System;
    using System.IO;
    using System.Net;
    using Newtonsoft.Json.Linq; //install Newtonsoft.Json via NuGet

    public static class Program
    {
        public static void Main(string[] args)
        {
            string imagesDir = Environment.CurrentDirectory + "\\Images";

            try
            {
                if (!Directory.Exists(imagesDir))
                {
                    Directory.CreateDirectory(imagesDir);
                }

                using (var client = new WebClient())
                {
                    string bingImageOfTheDayApi = "https://www.bing.com/HPImageArchive.aspx?format=js&idx=0&n=1";
                    string bingImageOfTheDayJson = client.DownloadString(bingImageOfTheDayApi);

                    //like python (or any other dynamically typed lang)
                    //dynamic is used to get the json's response for the image url
                    //no need to deserialize to a class
                    dynamic parsedJson = JObject.Parse(bingImageOfTheDayJson);
                    string imageUrl = "https://www.bing.com" + parsedJson.images[0].url;
                    string fileTitle = parsedJson.images[0].title;

                    var validFileName = (DateTime.Now.ToShortDateString() + "_" + fileTitle)
                        .Replace(" ", "-")
                        .Split(Path.GetInvalidFileNameChars());

                    string finalFileName = String.Join("-", validFileName) + ".jpg";

                    if (!File.Exists(imagesDir + "\\" + finalFileName))
                    {
                        Console.WriteLine($"Downloaded: {imageUrl} {Environment.NewLine}as{Environment.NewLine}{finalFileName}");
                        client.DownloadFile(imageUrl, imagesDir + "\\" + finalFileName);
                    }
                    else
                    {
                        Console.WriteLine("File has already been downloaded.");
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex);
            }
            finally
            {
                Console.WriteLine("---------------------------------------------------");
                Console.WriteLine("Press enter to exit.");
                Console.ReadLine();
            }
        }
    }
}