# ==============================================================================================
# 
# NAME: 	CheckXenAppIsFree.ps1
# 
# AUTHOR:	Alain Assaf 
# DATE   :	05/21/2009
# 
# COMMENT: 	Script that will run on a locked down server and automatically disconnect users 
#               until there are no more sessions.
# USAGE:	.\CheckXenAppIsFree.ps1
# ==============================================================================================

# Prompt for server to watch
if (($citrixserver -eq $null) -or ($citrixserver -eq "")){
	$citrixserver=$(Read-Host "Enter Server to watch until no sessions exist.")
}

# Setup Farm object
$MetaFrameWinAppObject = 3 
$MetaFrameWinFarmObject = 1 
$myFarm = New-Object -com MetaFrameCOM.MetaFrameFarm
$myFarm.Initialize($MetaFrameWinFarmObject)

# Checking if user is a Citrix administrator
If ($myFarm.WinFarmObject.IsCitrixAdministrator -eq 0) {
	Write-Output "You must be a Citrix admin to run this script`n"	
}

# Checking that the Citrix server exists
$MetaframeServers = $myFarm.Servers | Sort-Object -property ServerName | ? { $_.ServerName -like $citrixserver}
If ($MetaframeServers -eq $null) {
	Write-Host "Invalid Citrix server" -ForegroundColor Red
	Write-Host "Exiting CheckXenAppIsFree" -ForegroundColor Red
	break
}

# Getting the currently assigned load evaluator
$le = $MetaframeServers.AttachedLE
$le.loaddata(1)
$LEName = $le.LEName
$XenAppServerName = $citrixserver.ToUpper()

# If the LE isn't set to Lockdown, then this script will exit
If ($LEName -eq 'Lockdown') {
	Write-Host "$XenAppServerName has '$LEName' attached." -ForegroundColor White
} else {
	Write-Host "$XenAppServerName does not have a Lockdown LE attached.  It has '$LEName' attached." -ForegroundColor White
	Write-Host "Exiting CheckXenAppIsFree" -ForegroundColor Red
	break
}

# Get the current session count
$sessCount = $MetaframeServers.SessionCount

# Check for disconnected users.  If none, wait 10 minutes and check again
# If there are disconnected users.  Log them off.  Continue until there are no more logged in sessions.
while ($sessCount -ge 0) {
	$MetaframeServers = $myFarm.Servers | Sort-Object -property ServerName | ? { $_.ServerName -like $citrixserver}
	$sessCount = $MetaframeServers.SessionCount	
	Write-Host "Current session Count = $sessCount on $XenAppServerName" -ForegroundColor White
	if ($sessCount -eq 0) { Write-Host "$XenAppServerName is free of users" -ForegroundColor White
		break
	} else {
		$disconnected = @()
		Write-Host "Checking for disconnected users on $XenAppServername" -ForegroundColor White
		$disconnected = @($myfarm.Sessions | Where-Object {$_.SessionState -eq 5 -and $_.ServerName -eq $citrixserver})
		if ($disconnected[0] -eq $null) { 
			Write-Host "There are no currently disconnected sessions on $XenAppServerName" -ForegroundColor White 
			Write-Host "Waiting 10 minutes" -ForegroundColor Red
			Start-Sleep -Seconds 600
		} else {
			Write-host "Logging off disconnected users from $XenAppServerName" -ForegroundColor White
			$i = 0
			foreach ($user in $disconnected) {
				$namedUser = $disconnected[$i].Username
				write-host "Logging off $namedUser" -ForegroundColor White
				$user.Logoff($false)
				$sessCount--
				$i++
			}
		}
	}
}