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

namespace AmazonWebHelpers
{
    // Content item for the combo box
    public class AmazonItem
    {
        public string Title;
        public string ASIN;
        public string Artist;

        public AmazonItem(string title, string Asin, string artist)
        {
            Title = title; ASIN = Asin; Artist = artist;
        }
        public override string ToString()
        {
            // Generates the text shown in the combo box
            if (Artist == "")
                return Title + " [Various]";
            else
                return Title + " [" + Artist + "]";
        }
    }

    public class AmazonAlbumRetriever
    {
        #region private 
        private XmlNamespaceManager _ns;
        private XPathNavigator _nav;
        private string _proxyname;
        private string _proxypassword;
        private string _proxydomain;
        private string _wsKey;

        #endregion

        #region Constructor

        public AmazonAlbumRetriever(string WSKey){
        
            _proxydomain="";
            _proxyname="";
            _proxypassword="";
            _wsKey= WSKey;

            _ns = new XmlNamespaceManager(new NameTable());
            _ns.AddNamespace("asr", "http://webservices.amazon.com/AWSECommerceService/2007-01-15");
        }
            
        public AmazonAlbumRetriever(string WSKey,string ProxyName,string ProxyPassword,string ProxyDomain){
        
            _proxydomain=ProxyDomain;
            _proxyname=ProxyName;
            _proxypassword=ProxyPassword;
            _wsKey= WSKey;
            _ns = new XmlNamespaceManager(new NameTable());
            _ns.AddNamespace("asr", "http://webservices.amazon.com/AWSECommerceService/2007-01-15");
        }
        

        #endregion // Constructor
                       
        #region Property
        /// <summary>
        /// The XMLNavigator for the loaded page.
        /// </summary>
        public XPathNavigator XMLNavigator
        {
            get
            {
                if (_nav==null)
                     throw new ArgumentException("The XmlNavigator must be initialised before it is accessed.");
                else
                return _nav;
            }
        }

        public int GetArtistAlbumResultsLength
        {
            get
            {
                if (_nav == null)
                {
                    throw new ArgumentException("The XmlNavigator must be initialised before it is accessed.");
                }
                else
                {

                    try
                    {
                        return this._nav.SelectSingleNode("/asr:ItemSearchResponse/asr:Items/asr:TotalResults", this._ns).ValueAsInt;
                    }
                    catch
                    {
                        return 0;
                    }
                }
            }
        }

        public int GetArtistAlbumPagesNo
        {
            get{
                if (_nav == null)
                {
                    throw new ArgumentException("The XmlNavigator must be initialised before it is accessed.");
                }
                else
                {

                    try
                    {
                        return this._nav.SelectSingleNode("/asr:ItemSearchResponse/asr:Items/asr:TotalPages", this._ns).ValueAsInt;
                    }
                    catch
                    {
                        return 0;
                    }
                }
            }

        }
        #endregion

        #region Methods
        public string GetAlbumImageURL(string ASIN)
        {
            HttpWebRequest request;
            HttpWebResponse response;
            XPathNavigator nav;
            XPathNavigator resnav;
                        
            try
            {
                string uri = "http://ecs.amazonaws.com/onca/xml?Service=AWSECommerceService&AWSAccessKeyId=" + this._wsKey + "&Operation=ItemLookup&AssociateTag=devconn-20&Version=2007-01-15&ItemId=" + ASIN + "&ResponseGroup=Images";
                request = (HttpWebRequest)WebRequest.Create(uri);
                request.Method = "GET";

                //set proxy auth if required
                if (this._proxyname != "")
                {
                    if (this._proxydomain == "")
                        request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword);
                    else
                        request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword,this._proxydomain);

                }
                    response = (HttpWebResponse)request.GetResponse();
                    if (response.StatusCode == HttpStatusCode.OK)
                    {
                        nav = new XPathDocument(response.GetResponseStream()).CreateNavigator();
                        resnav = nav.SelectSingleNode("/asr:ItemLookupResponse/asr:Items/asr:Item/asr:LargeImage/asr:URL", this._ns);
                        return resnav.ToString();
                    }
                
                return "";

            }
            catch
            {
                return "";
            }

        }


        public string[] GetAlbumtracks(string ASIN)
        {
            HttpWebRequest request;
            HttpWebResponse response;
            XPathNavigator nav;
            XPathNodeIterator nitr;
            List<string> Tracks = new List<string>();

            XPathNavigator resnav;

            try
            {
                string uri = "http://ecs.amazonaws.com/onca/xml?Service=AWSECommerceService&AWSAccessKeyId=" + this._wsKey + "&Operation=ItemLookup&AssociateTag=devconn-20&Version=2007-01-15&ItemId=" + ASIN + "&ResponseGroup=Tracks";
                request = (HttpWebRequest)WebRequest.Create(uri);
                request.Method = "GET";

                //set proxy auth if required
                if (this._proxyname != "")
                {
                    if (this._proxydomain == "")
                        request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword);
                    else
                        request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword, this._proxydomain);

                }
                response = (HttpWebResponse)request.GetResponse();
                if (response.StatusCode == HttpStatusCode.OK)
                {
                    nav = new XPathDocument(response.GetResponseStream()).CreateNavigator();
                    nitr = this._nav.Select("/asr:ItemLookupResponse/asr:Items/asr:Item/asr:Tracks/asr:Disc/asr:Track", this._ns);
                    while (nitr.MoveNext())
                    {
                        Tracks.Add(nitr.Current.Value);
                    }
                                        
                }

                return Tracks.ToArray();

            }
            catch
            {
                return new List<string>().ToArray();
            }

        }
        public List<AmazonItem> GetArtistAlbumList(string artistname,int Page)
        {
            HttpWebRequest request;
            HttpWebResponse response;

            XPathNodeIterator nitr;
            
            string CurrentASIN="";
            string CurrentTitle = "";
            string CurrentArtist = "";
            List<AmazonItem> ItemList = new List<AmazonItem>();

            string uri = "http://ecs.amazonaws.com/onca/xml?Service=AWSECommerceService&AWSAccessKeyId=" + this._wsKey + "&Operation=ItemSearch&AssociateTag=&Version=2007-01-15&SearchIndex=Music&Artist=" + artistname + "&ItemPage=" + Page.ToString();
            try
            {

                request = (HttpWebRequest)WebRequest.Create(uri);
                request.Method = "GET";

                //set proxy auth if required
                if (this._proxyname != "")
                {
                    if (this._proxydomain == "")
                        request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword);
                    else
                        request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword, this._proxydomain);

                }

                response = (HttpWebResponse)request.GetResponse();

                this._nav = new XPathDocument(response.GetResponseStream()).CreateNavigator();
                               //Check that we got a result
                if (this.GetArtistAlbumResultsLength != 0)
                {
                    if (Page <= this.GetArtistAlbumPagesNo){
                   
                        nitr = this._nav.Select("/asr:ItemSearchResponse/asr:Items/asr:Item", this._ns);
                        while (nitr.MoveNext())
                        {
                            XPathNodeIterator _nodeChildren = nitr.Current.SelectChildren(XPathNodeType.All);
                            while (_nodeChildren.MoveNext())
                            {
                                if (_nodeChildren.Current.LocalName == "ASIN")
                                    CurrentASIN = _nodeChildren.Current.Value;

                                if (_nodeChildren.Current.LocalName == "ItemAttributes")
                                {
                                    XPathNodeIterator _nodegChildren = _nodeChildren.Current.SelectChildren(XPathNodeType.All);
                                    while (_nodegChildren.MoveNext())
                                    {
                                        if (_nodegChildren.Current.LocalName == "Title")
                                            CurrentTitle = _nodegChildren.Current.Value;
                                        if (_nodegChildren.Current.LocalName == "Artist")
                                            CurrentArtist = _nodegChildren.Current.Value;

                                    }
                                                                    

                                }
                                
                            }
                            if (CurrentTitle != "" && CurrentASIN != "")
                            {
                                ItemList.Add(new AmazonItem(CurrentTitle,CurrentASIN, CurrentArtist));
                            }
                            CurrentTitle = "";
                            CurrentASIN = "";
                            CurrentArtist = "";
                        }
                       
                       
                    }
                }

                return ItemList;

            }
            catch
            {
                ItemList.Clear();
                return ItemList;
            }

        }
        public byte[] DownloadImagetobytes(string uri)
        {

            Stream stream = null;

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
            request.Method = "GET";

            //set proxy auth if required
            if (this._proxyname != "")
            {
                if (this._proxydomain == "")
                    request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword);
                else
                    request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword, this._proxydomain);

            }

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            stream = response.GetResponseStream();

            return ReadFully(stream, 32768);

        }
        public Stream DownloadImagetoStream(string uri)
        {

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
            request.Method = "GET";

            //set proxy auth if required
            if (this._proxyname != "")
            {
                if (this._proxydomain == "")
                    request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword);
                else
                    request.Proxy.Credentials = new NetworkCredential(this._proxyname, this._proxypassword, this._proxydomain);

            }

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            return response.GetResponseStream();

        }
        private static byte[] ReadFully(Stream stream, int initialLength)
        {
            if (initialLength < 1)
            {
                initialLength = 32768;
            }

            byte[] buffer = new byte[initialLength];
            int read = 0;

            int chunk;
            while ((chunk = stream.Read(buffer, read, buffer.Length - read)) > 0)
            {
                read += chunk;

                /* If we've reached the end of our buffer, check to see if there's
                 any more information */
                if (read == buffer.Length)
                {
                    int nextByte = stream.ReadByte();

                    /* End of stream? If so, we're done */
                    if (nextByte == -1)
                    {
                        return buffer;
                    }

                    /* Nope. Resize the buffer, put in the byte we've just
                     read, and continue */
                    byte[] newBuffer = new byte[buffer.Length * 2];
                    Array.Copy(buffer, newBuffer, buffer.Length);
                    newBuffer[read] = (byte)nextByte;
                    buffer = newBuffer;
                    read++;
                }
            }
            /* Buffer is now too big. Shrink it. */
            byte[] ret = new byte[read];
            Array.Copy(buffer, ret, read);
            return ret;
        }
        #endregion
    }
}