#region Copyright (C) 2005-2011 Team MediaPortal



// Copyright (C) 2005-2011 Team MediaPortal

// http://www.team-mediaportal.com

// 

// MediaPortal is free software: you can redistribute it and/or modify

// it under the terms of the GNU General Public License as published by

// the Free Software Foundation, either version 2 of the License, or

// (at your option) any later version.

// 

// MediaPortal is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

// GNU General Public License for more details.

// 

// You should have received a copy of the GNU General Public License

// along with MediaPortal. If not, see <http://www.gnu.org/licenses/>.



#endregion



using System;

using System.Runtime.InteropServices;

using System.Text;

using System.ComponentModel;



namespace TvLibrary.Helper

{

  /// <summary>

  /// SID Helper methods

  /// </summary>

  public class SidHelper

  {

    #region imports



    [DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]

    private static extern bool LookupAccountSid(

      [In, MarshalAs(UnmanagedType.LPTStr)] string systemName,

      IntPtr sid,

      [Out, MarshalAs(UnmanagedType.LPTStr)] StringBuilder name,

      ref int cbName,

      StringBuilder referencedDomainName,

      ref int cbReferencedDomainName,

      out int use);



    [DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]

    private static extern bool LookupAccountName(

      [In, MarshalAs(UnmanagedType.LPTStr)] string systemName,

      [In, MarshalAs(UnmanagedType.LPTStr)] string accountName,

      IntPtr sid,

      ref int cbSid,

      StringBuilder referencedDomainName,

      ref int cbReferencedDomainName,

      out int use);



    [DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]

    internal static extern bool ConvertSidToStringSid(

      IntPtr sid,

      [In, Out, MarshalAs(UnmanagedType.LPTStr)] ref string pStringSid);



    [DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]

    internal static extern bool ConvertStringSidToSid(

      [In, MarshalAs(UnmanagedType.LPTStr)] string pStringSid,

      ref IntPtr sid);



    #endregion



    ///<summary>

    /// Gets the SID pointer

    ///</summary>

    ///<param name="name">Name</param>

    ///<returns>Pointer to the SID</returns>

    public static IntPtr GetSidPtr(string name)

    {

      IntPtr _sid = IntPtr.Zero; //pointer to binary form of SID string.

      int _sidLength = 0; //size of SID buffer.

      int _domainLength = 0; //size of domain name buffer.

      int _use; //type of object.

      //stringBuilder for domain name.

      StringBuilder _domain = new StringBuilder();



      //first call of the function only returns the size 

      //of buffers (SID, domain name)

      LookupAccountName(null, name, _sid, ref _sidLength, _domain,

                        ref _domainLength, out _use);

      int _error = Marshal.GetLastWin32Error();



      //error 122 (The data area passed to a system call is too small) 

      // normal behaviour.

      if (_error != 122)

      {

        return IntPtr.Zero;

      }

      //allocates memory for domain name

      _domain = new StringBuilder(_domainLength);

      //allocates memory for SID

      _sid = Marshal.AllocHGlobal(_sidLength);

      bool _rc = LookupAccountName(null, name, _sid, ref _sidLength, _domain,

                                   ref _domainLength, out _use);



      if (_rc == false)

      {

        Marshal.GetLastWin32Error();

        Marshal.FreeHGlobal(_sid);

        return IntPtr.Zero;

      }

      return _sid;

    }



    /// <summary>

    /// Gets the SID

    /// </summary>

    /// <param name="name">Name</param>

    /// <returns>SID</returns>

    public static string GetSid(string name)

    {

      IntPtr _sid = IntPtr.Zero; //pointer to binary form of SID string.

      int _sidLength = 0; //size of SID buffer.

      int _domainLength = 0; //size of domain name buffer.

      int _use; //type of object.

      //stringBuilder for domain name.

      StringBuilder _domain = new StringBuilder();

      string _sidString = "";



      //first call of the function only returns the size 

      //of buffers (SID, domain name)

      LookupAccountName(null, name, _sid, ref _sidLength, _domain,

                        ref _domainLength, out _use);

      int _error = Marshal.GetLastWin32Error();



      //error 122 (The data area passed to a system call is too small) 

      // normal behaviour.

      if (_error != 122)

      {

        throw (new Exception(new Win32Exception(_error).Message));

      }

      //allocates memory for domain name

      _domain = new StringBuilder(_domainLength);

      //allocates memory for SID

      _sid = Marshal.AllocHGlobal(_sidLength);

      bool _rc = LookupAccountName(null, name, _sid, ref _sidLength, _domain,

                                   ref _domainLength, out _use);



      if (_rc == false)

      {

        _error = Marshal.GetLastWin32Error();

        Marshal.FreeHGlobal(_sid);

        throw (new Exception(new Win32Exception(_error).Message));

      }

      // converts binary SID into string

      _rc = ConvertSidToStringSid(_sid, ref _sidString);



      if (_rc == false)

      {

        _error = Marshal.GetLastWin32Error();

        Marshal.FreeHGlobal(_sid);

        throw (new Exception(new Win32Exception(_error).Message));

      }

      Marshal.FreeHGlobal(_sid);

      return _sidString;

    }



    /// <summary>

    /// Gets the name to the given sid

    /// </summary>

    /// <param name="sid">The SID</param>

    /// <returns>Name to the SID</returns>

    public static string GetName(string sid)

    {

      IntPtr _sid = IntPtr.Zero; //pointer to binary form of SID string.

      int _nameLength = 0; //size of object name buffer

      int _domainLength = 0; //size of domain name buffer

      int _use; //type of object

      StringBuilder _domain = new StringBuilder(); //domain name variable

      StringBuilder _name = new StringBuilder(); //object name variable



      //converts SID string into the binary form

      bool _rc0 = ConvertStringSidToSid(sid, ref _sid);



      if (_rc0 == false)

      {

        Marshal.GetLastWin32Error();

        Marshal.FreeHGlobal(_sid);

        return String.Empty;

      }



      //first call of method returns the size of domain name 

      //and object name buffers

      LookupAccountSid(null, _sid, _name, ref _nameLength, _domain,

                       ref _domainLength, out _use);

      _domain = new StringBuilder(_domainLength); //allocates memory for domain name

      _name = new StringBuilder(_nameLength); //allocates memory for object name

      bool _rc = LookupAccountSid(null, _sid, _name, ref _nameLength, _domain,

                                  ref _domainLength, out _use);



      if (_rc == false)

      {

        Marshal.GetLastWin32Error();

        Marshal.FreeHGlobal(_sid);

        return String.Empty;

      }

      Marshal.FreeHGlobal(_sid);

      return _domain + "\\" + _name;

    }

  }

}