Param (
    [Parameter(Mandatory=$true,
        Position=0,
        ValueFromPipeline=$true,
        HelpMessage="DN or ObjectGUID of the AD Group."
    )]
    [string]$groupIdentity,
    [switch]$showTree
    )
#Validate Quest PSSnapin is loaded
Add-PSSnapin -Name Quest.ActiveRoles.ADManagement -ErrorAction SilentlyContinue
$global:numberOfRecursiveGroupMemberships = 0
$lastGroupAtALevelFlags = @() 

function Get-GroupNesting ([string] $identity, [int] $level, [hashtable] $groupsVisitedBeforeThisOne, [bool] $lastGroupOfTheLevel)
{
    $group = $null
    $group = Get-QADGroup -Identity $identity -SizeLimit 0
    if($lastGroupAtALevelFlags.Count -le $level)
    {
        $lastGroupAtALevelFlags = $lastGroupAtALevelFlags + 0
    }
    if($group -ne $null)
    {
        if($showTree)
        {
            for($i = 0; $i -lt $level - 1; $i++)
            {
                if($lastGroupAtALevelFlags[$i] -ne 0)
                {
                    Write-Host -ForegroundColor Blue -NoNewline "  "
                }
                else
                {
                    Write-Host -ForegroundColor Blue -NoNewline "„  "
                }
            }
            if($level -ne 0)
            {
                if($lastGroupOfTheLevel)
                {
                    Write-Host -ForegroundColor Blue -NoNewline "„¤„Ÿ"
                }
                else
                {
                    Write-Host -ForegroundColor Blue -NoNewline "„¥„Ÿ"
                }
            }
            Write-Host -ForegroundColor Blue $group.Name
        }
        $groupsVisitedBeforeThisOne.Add($group.DN,$null)
        $global:numberOfRecursiveGroupMemberships ++
        $groupMemberShipCount = $group.memberOf.Count
        if ($groupMemberShipCount -gt 0)
        {
            $maxMemberGroupLevel = 0
            $count = 0
            foreach($groupDN in $group.memberOf)
            {
                $count++
                $lastGroupOfThisLevel = $false
                if($count -eq $groupMemberShipCount){$lastGroupOfThisLevel = $true; $lastGroupAtALevelFlags[$level] = 1}
                if(-not $groupsVisitedBeforeThisOne.Contains($groupDN)) #prevent cyclic dependancies
                {
                    $memberGroupLevel = Get-GroupNesting -Identity $groupDN -Level $($level+1) -GroupsVisitedBeforeThisOne $groupsVisitedBeforeThisOne -lastGroupOfTheLevel $lastGroupOfThisLevel
                    if ($memberGroupLevel -gt $maxMemberGroupLevel){$maxMemberGroupLevel = $memberGroupLevel}
                }
            }
            $level = $maxMemberGroupLevel
        }
        else #we've reached the top level group, return it's height
        {
            return $level
        }
        return $level
    }
}
$global:numberOfRecursiveGroupMemberships = 0
$groupObj = Get-QADGroup -Identity $groupIdentity -SizeLimit 0
if($groupObj)
{
    [int]$maxNestingLevel = Get-GroupNesting -Identity $groupIdentity -Level 0 -GroupsVisitedBeforeThisOne @{} -lastGroupOfTheLevel $false
	Add-Member -InputObject $groupObj -MemberType NoteProperty  -Name MaxNestingLevel -Value $maxNestingLevel -Force
    Add-Member -InputObject $groupObj -MemberType NoteProperty  -Name NestedGroupMembershipCount -Value $($global:numberOfRecursiveGroupMemberships - 1) -Force
	$groupObj | Select-Object Name,DN,MaxNestingLevel,NestedGroupMembershipCount | Format-List
}