using System;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.Net;
using System.IO;
using System.Xml;

namespace GetITunesCoverArt {

    class Program {

        static void Main( string[] args ) {

            string artist; string album;
            if (args.Length == 2) {
                artist = HttpUtility.UrlEncode(args[0]);
                album = HttpUtility.UrlEncode(args[1]);
            } else {
                artist = "Dire Straits";
                album = "Sultans of swing";
            }

            string url = String.Format(urlBase, artist, album);

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            // wipe old headers
            request.Headers.Clear();
            request.Headers.Add("X-Apple-Tz", "7200");
            request.Headers.Add("X-Apple-Store-Front", store.ToString());
            request.Headers.Add("Accept-Language", "en-us, en;q=0.50");
            request.Headers.Add("Accept-Encoding", "gzip, x-aes-cbc");
            request.UserAgent = userAgent;
            request.AutomaticDecompression = DecompressionMethods.GZip;

            string imageUrl = null;

            using (HttpWebResponse response = (HttpWebResponse)request.GetResponse()) {

                using (Stream stream = response.GetResponseStream()) {


                    XmlDocument doc = new XmlDocument();
                    doc.Load(stream);
                    XmlNamespaceManager xnm = new XmlNamespaceManager(doc.NameTable);
                    xnm.AddNamespace("a", ns);

                    XmlNodeList nodes = doc.SelectNodes("/a:Document/a:Protocol/a:plist/a:dict/a:string", xnm);

                    imageUrl = nodes[0].InnerText;
                }

                response.Close();
            }

            if (String.IsNullOrEmpty(imageUrl)) {
                Console.Write("No image found.");
            } else {

                DownLoadImage(imageUrl, String.Format("{0}.{1}.jpg", artist, album));
                                                                                                                                                                                                    ;
                Console.WriteLine("done");
            }
            Console.ReadLine();
        }

        private static void DownLoadImage( string imageUrl, string fileName ) {

            HttpWebRequest imgRequest = (HttpWebRequest)WebRequest.Create(imageUrl);

            using (HttpWebResponse response = (HttpWebResponse)imgRequest.GetResponse())
            using (Stream stream = response.GetResponseStream())
            using (FileStream file = new FileStream(fileName, FileMode.Create)) {
                long total = 0;
                int count = 1024;
                byte[] buffer = new byte[count];

                while (count > 0) {
                    count = stream.Read(buffer, 0, buffer.Length);
                    total += count;
                    file.Write(buffer, 0, count);
                }
                file.Flush();
            }
        }

        // CONSTANTS
        const string userAgent = "iTunes/7.0 (Macintosh; U; PPC Mac OS X 10.4.7)";
        const string urlBase = "http://ax.phobos.apple.com.edgesuite.net/WebObjects/MZSearch.woa/wa/coverArtMatch?an={0}&pn={1}";
        const string ns = "http://www.apple.com/itms/";
        const int store = 143457;

    }
}