using System;
using System.Collections;
using System.Data;
using System.Diagnostics;
using System.IO;
using System.Net;
using System.Reflection;
using System.Text;
using System.Web;
using ICSharpCode.SharpZipLib.Zip.Compression.Streams;

namespace Ip2CountryLib
{
 public class CountryLookup
 {
  private string theCountries = String.Empty;
  private string theLatLong = String.Empty;

  private static string[] countryCodes =
   {
    "AP", "EU", "AD", "AE", "AF" ....
   };

  private static string[] countryNames =
   {
    "Asia/Pacific Region", "Europe", "Andorra", "United Arab Emirates", "Afghanistan", ...
   };

  private Hashtable htCountryNames = new Hashtable();
  private DataTable IP2CountryTable = new DataTable();
  private DataTable CountryLatLongTable = new DataTable();
  private string foundCountry;
  private string foundCountryLong;
  private decimal latitude;
  private decimal longitude;

  public string FoundCountryLong
  {
   get { return foundCountryLong; }
   set { foundCountryLong = value; }
  }

  public Decimal Latitude
  {
   get { return latitude; }
   set { latitude = value; }
  }

  public Decimal Longitude
  {
   get { return longitude; }
   set { longitude = value; }
  }

  public string FoundCountry
  {
   get { return foundCountry; }
  }

  private long addrToNum(IPAddress addr)
  {
   long ipnum = 0;

   byte[] b = BitConverter.GetBytes(addr.Address);
   for (int i = 0; i < 4; ++i)
   {
    long y = b[i];
    if (y < 0)
    {
     y += 256;
    }
    ipnum += y << ((3 - i)*8);
   }
   //Console.WriteLine(ipnum);
   return ipnum;
  }

  public void FindCountryByDottedIp(string dottedQuadIp)
  {
   IPAddress addr = IPAddress.Parse(dottedQuadIp);
   long num = addrToNum(addr);
   

   foreach (DataRow row in IP2CountryTable.Rows)
   {
    if (Convert.ToDouble(row[0]) <= num && Convert.ToDouble(row[1]) >= num)
    {
     this.foundCountry = row[2].ToString();     
     DataRow[] fndLats = this.CountryLatLongTable.Select("CountryCode='" + this.foundCountry + "'");
     DataRow fndLat = fndLats[0];

     this.foundCountryLong = (string) this.htCountryNames[foundCountry];
     this.latitude = Convert.ToDecimal(fndLat[1]);
     this.longitude = Convert.ToDecimal(fndLat[2]);
     break;
    }
   } // end foreach
  } //end method
  public CountryLookup()
  {
   for (int i = 0; i < CountryLookup.countryCodes.Length; i++)
   {
    this.htCountryNames.Add(CountryLookup.countryCodes[i], CountryLookup.countryNames[i]);
   }

   if (HttpContext.Current.Cache["CountryLatLongTable"] == null)
   {
    theLatLong = GetDecompressedResourceString("IP2CountryLib.CountryLatLong.txt",false);
    this.CountryLatLongTable.Columns.Add("CountryCode", typeof (string));
    this.CountryLatLongTable.Columns.Add("Latitude", typeof (string));
    this.CountryLatLongTable.Columns.Add("Longitude", typeof (string));
    CountryLatLongTable.Columns["CountryCode"].Unique = true;
    string[] countries = theLatLong.Split(new char[] {'\n'});
    for (int i = 0; i < countries.Length; i++)
    {
     object[] theRow = countries[i].Split(new Char[] {'|'});
     CountryLatLongTable.Rows.Add(theRow);
    }
    CountryLatLongTable.AcceptChanges();  
    HttpContext.Current.Cache["CountryLatLongTable"] = CountryLatLongTable;
   }
   else
   {
    CountryLatLongTable = (DataTable) HttpContext.Current.Cache["CountryLatLongTable"];
   }

   if (HttpContext.Current.Cache["IP2CountryTable"] == null)
   {
    theCountries = GetDecompressedResourceString("IP2CountryLib.IP2Country.dat",true);
    IP2CountryTable.Columns.Add("BeginIp", typeof (long));
    IP2CountryTable.Columns.Add("EndIp", typeof (long));
    IP2CountryTable.Columns.Add("CountryCode", typeof (string));

    string[] countries = theCountries.Split(new Char[] {'\n'});
    for (int i = 0; i < countries.Length; i++)
    {
     countries[i] = countries[i].Replace("\r", ""); // cleanup
     object[] theRow = countries[i].Split(new Char[] {'|'});
     IP2CountryTable.Rows.Add(theRow);
    }
    IP2CountryTable.AcceptChanges();
    HttpContext.Current.Cache["IP2CountryTable"] = IP2CountryTable;
   }
   else
   {
    IP2CountryTable = (DataTable) HttpContext.Current.Cache["IP2CountryTable"];
   }
  }

  private string GetDecompressedResourceString(string resource,bool IsCompressed)
  {
   string theResource=String.Empty;
   byte[] bytInput = null;
            Stream stm=null;
   BinaryReader br=null;
   try
   {
    Assembly asm = Assembly.GetExecutingAssembly();
    stm = asm.GetManifestResourceStream(resource);
     br = new BinaryReader(stm);
    long siz = stm.Length;
    
    bytInput = br.ReadBytes((int) siz);
    if(IsCompressed)
    {
     theResource = Decompress(bytInput);
    }
    else
    {
     theResource=System.Text.Encoding.UTF8.GetString(bytInput) ;
    }
   }
   catch (Exception ex)
   {
    throw new ApplicationException(ex.Message);
   }
   finally
   {
    br.Close();
    stm.Close();
   }
   return theResource;
  }

  private string Decompress(byte[] bytInput)
  {
   string strResult = "";
   int totalLength = 0;
   byte[] writeData = new byte[4096];
   Stream s2 = new InflaterInputStream(new MemoryStream(bytInput));
   try
   {
    while (true)
    {
     int size = s2.Read(writeData, 0, writeData.Length);
     if (size > 0)
     {
      totalLength += size;
      strResult += Encoding.UTF8.GetString(writeData, 0,size);
     }
     else
     {
      break;
     }
    }
    s2.Close();
    return strResult;
   }
   catch 
   {
    throw; 
   }
  }
 }
}