#Usage DeleteSCOMAgents.ps1 -MSServer "zOM01.scom2k12.com" -AgentComputerName "xSP01.scom2k12.com", "xDV02.scom2k12.com"


Param(
  [string[]]$AgentComputerName,
  [string]$MSServer
)

[System.Reflection.Assembly]::Load("Microsoft.EnterpriseManagement.Core, Version=7.0.5000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35")
[System.Reflection.Assembly]::Load("Microsoft.EnterpriseManagement.OperationsManager, Version=7.0.5000.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35")



function New-Collection ( [type] $type ) 
{
	$typeAssemblyName = $type.AssemblyQualifiedName;
	$collection = new-object "System.Collections.ObjectModel.Collection``1[[$typeAssemblyName]]";
	return ,($collection);
}




# Connect to management group
Write-output "Connecting to management group"

$ConnectionSetting = New-Object Microsoft.EnterpriseManagement.ManagementGroup($MSServer)
$admin = $ConnectionSetting.GetAdministration()


Write-output "Getting agent managed computers"
$agentManagedComputers = $admin.GetAllAgentManagedComputers()

# Get list of agents to delete
foreach ($name in $AgentComputerName) 
{
    Write-output "Checking for $name"
    foreach ($agent in $agentManagedComputers)
    {
        if ($deleteCollection -eq $null) 
        {
            $deleteCollection = new-collection $agent.GetType()
        }

        
        if (@($agent.PrincipalName -eq $name))
        {
	    Write-output "Matched $name"
            $deleteCollection.Add($agent)
            break
        }
    }
}

if ($deleteCollection.Count -gt 0) 
{
    Write-output "Deleting agents"
    $admin.DeleteAgentManagedComputers($deleteCollection)
    if($?){ Write-output "Agents deleted" }
}