# get-sendaspermission
#
# Only direct SendAs for USers. No Group support
# run in Exhcange PowerShell

param (
	[string]$exportfile = ".\sendaspermission.csv" ,
	[string]$resultsize = "unlimited"   # set to unlimited
)

Write-Host "Export-SendAsPermission: Start"
# -- delete existing file
Remove-Item $exportfile -ErrorAction SilentlyContinue

# --- Load mailboxes
Write-Host "Load $($resultsize) Mailboxes from Exchange..."
$Mailboxes = Get-Mailbox -ResultSize $resultsize | Select-Object DistinguishedName,PrimarySmtpAddress,Name
Write-Host "Total Mailboxes: $($Mailboxes.count)"

Write-Host "Load $($resultsize) RemoteMailboxes from Exchange..."
$RemoteMailboxes = Get-RemoteMailbox -ResultSize $resultsize | Select-Object DistinguishedName,PrimarySmtpAddress,Name
Write-Host "Total RemoteMailboxes: $($RemoteMailboxes.count)"

Write-host "Merge Maiboxes/RemoteMailboxes"
$Totalmailboxes = $Mailboxes + $RemoteMailboxes
Write-Host "Total Items to process: $($TotalMailboxes.count)"

# --- Process mailbox/remotemailbox
$count = 0
ForEach ($Mailbox in $Totalmailboxes) {
	$count = $count + 1
	write-host "( $($count)/$($TotalMailboxes.Count)) Mailbox $($Mailbox.PrimarySmtpAddress)"
	$result = [pscustomobject][ordered]@{
				MailboxEmail = $Mailbox.PrimarySmtpAddress
				MailboxName = $Mailbox.Name
				SendAsUser = ""
				SendAsUserMail = ""
	}

	$Delegates = @()
	$Delegates = Get-ADPermission -identity $Mailbox.DistinguishedName `
	| Where-Object {($_.ExtendedRights -like "*send-as*")}
	If ($null -eq $Delegates) {
		write-host "  No SendAs Permission"
	}
	else {
		write-host "  Parsing SendAs Permission"
		ForEach ($Delegate in $Delegates) {
			write-host "   Delegate $($Delegate.identity)"
			$CheckDelegate = Get-Recipient $Delegate.User.RawIdentity -ErrorAction SilentlyContinue
			If ($null -eq $CheckDelegate) {
				Write-host "    Skip - No Mailbox"
			}
			elseif ($CheckDelegate.distinguishedname -eq $Mailbox.DistinguishedName) {
				write-host "  Skip Self"
			}
			else {
				If (($CheckDelegate.RecipientType -like "Mail*") `
				-or $CheckDelegate.RecipientType -like "*Mailbox") {
					$result.SendAsUser = $CheckDelegate.Name
					$result.SendAsUserMail = $CheckDelegate.PrimarySmtpAddress
					write-host "  Export Line" -ForegroundColor Green
					$result | export-csv $exportfile -append -NoTypeInformation
				}
			}
		}
	}
}

Write-Host "Export-SendAsPermission: End"