using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;
using System.Xml;
using System.Xml.Linq;

namespace OpenAPISampleNET
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("--- Download data sample ---");
            WebClient webclient = new WebClient();
            webclient.Headers.Add("Referer", "http://www.example.com"); // Replace with your domain here
            // Registrer a handler that will execute when download is completed.
            webclient.UploadStringCompleted += (obj, arguments) =>
            {
                if (arguments.Cancelled == true)
                {
                    Console.Write("Request cancelled by user");
                }
                else if (arguments.Error != null)
                {
                    Console.WriteLine(arguments.Error.Message);
                    Console.Write("Request Failed");
                }
                else
                {
                    Console.WriteLine(formatXML(arguments.Result));
                    Console.Write("Data downloaded");
                }
                Console.WriteLine(", press 'X' to exit.");
            };

            try
            {
                // API server url
                Uri address = new Uri("https://api.trafikinfo.trafikverket.se/v2/data.xml");
                string requestBody = "<REQUEST>" +
                    // Use your valid authenticationkey
                                        "<LOGIN authenticationkey='yourAuthenticationKey'/>" +
                                        "<QUERY objecttype='TrainMessage' schemaversion='1.3'>" +
                                            "<FILTER>" +
                                                "<IN name='AffectedLocation' value='Blg'/>" +
                                            "</FILTER>" +
                                            "<EXCLUDE>Deleted</EXCLUDE>" +
                                        "</QUERY>" +
                                    "</REQUEST>";

                webclient.Headers["Content-Type"] = "text/xml";
                Console.WriteLine("Fetching data ... (press 'C' to cancel)");
                webclient.UploadStringAsync(address, "POST", requestBody);
            }
            catch (UriFormatException)
            {
                Console.WriteLine("Malformed url, press 'X' to exit.");
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
                Console.WriteLine("An error occured, press 'X' to exit.");
            }

            char keychar = ' ';
            while (keychar != 'X')
            {
                keychar = Char.ToUpper(Console.ReadKey().KeyChar);
                if (keychar == 'C')
                {
                    webclient.CancelAsync();
                }
            }
        }

        // Format xml so it is readable by humans.
        private static string formatXML(string xml)
        {
            // Format xml.
            XDocument rxml = XDocument.Parse(xml);
            XmlWriterSettings xmlsettings = new XmlWriterSettings();
            xmlsettings.OmitXmlDeclaration = true;
            xmlsettings.Indent = true;
            xmlsettings.IndentChars = "      ";
            var sb = new StringBuilder();
            using (XmlWriter xmlWriter = XmlWriter.Create(sb, xmlsettings))
            {
                rxml.WriteTo(xmlWriter);
            }
            return sb.ToString();
        }
    }
}