using System;
using System.Collections.Generic;
using System.DirectoryServices;
using System.DirectoryServices.AccountManagement;
using System.Linq;

public static class DirectoryServiceUtils
{
	private static IList<string> _DomainGroupList = null;
	public static IList<string> DomainGroupList
	{
		get
		{
			if (_DomainGroupList == null)
			{
				_DomainGroupList = new List<string>();
				GetGroups(x => { _DomainGroupList.Add(x.SamAccountName); return true; });
			}
			return _DomainGroupList;
		}
	}
	public static IList<Principal> GetGroups(ContextType contextType = ContextType.Domain, string name = null, string container = null, ContextOptions options = ContextOptions.Negotiate | ContextOptions.Signing | ContextOptions.Sealing, string userName = null, string password = null, int pageSize = 1000, SearchScope searchScope = SearchScope.Subtree)
	{
		using (PrincipalContext context = new PrincipalContext(contextType, name, container, options, userName, password))
		{
			using (GroupPrincipal principal = new GroupPrincipal(context))
			{
				principal.GroupScope = GroupScope.Global;
				using (PrincipalSearcher principalSearcher = new PrincipalSearcher(principal))
				{
					DirectorySearcher directorySearcher = principalSearcher.GetUnderlyingSearcher() as DirectorySearcher;
					directorySearcher.PageSize = pageSize;
					directorySearcher.SearchScope = searchScope;
					return principalSearcher.FindAll().ToList();
				}
			}
		}
	}
	public static string GetGroups(string separator = ",", ContextType contextType = ContextType.Domain, string name = null, string container = null, ContextOptions options = ContextOptions.Negotiate | ContextOptions.Signing | ContextOptions.Sealing, string userName = null, string password = null, int pageSize = 1000, SearchScope searchScope = SearchScope.Subtree)
	{
		return String.Join(separator, GetGroups(contextType, name, container, options, userName, password, pageSize, searchScope).Select(x => x.SamAccountName).ToArray());
	}
	public static void GetGroups(Func<GroupPrincipal, bool> func, ContextType contextType = ContextType.Domain, string name = null, string container = null, ContextOptions options = ContextOptions.Negotiate | ContextOptions.Signing | ContextOptions.Sealing, string userName = null, string password = null, int pageSize = 1000, SearchScope searchScope = SearchScope.Subtree)
	{
		using (PrincipalContext context = new PrincipalContext(contextType, name, container, options, userName, password))
		{
			using (GroupPrincipal principal = new GroupPrincipal(context))
			{
				principal.GroupScope = GroupScope.Global;
				using (PrincipalSearcher principalSearcher = new PrincipalSearcher(principal))
				{
					DirectorySearcher directorySearcher = principalSearcher.GetUnderlyingSearcher() as DirectorySearcher;
					directorySearcher.PageSize = pageSize;
					directorySearcher.SearchScope = searchScope;
					foreach (Principal result in principalSearcher.FindAll())
					{
						if (func != null && !func(result as GroupPrincipal))
							break;
					}
				}
			}
		}
	}
}