Script to format mobile numbers in Active Directory

phonesanitisation.ps1

#Get's all enabled users from the all users group which is populated nightly.
$usersall = Get-ADUser -Filter *

#Declare pattern match to remove non integer characters.
$numpattern = '[^0-9]'

#Iterate through users applying replaced value
$users | ForEach-Object {
    $regexedmobile = $_.mobile -replace $numpattern,''
    $userobj = [pscustomobject]@{
            samaccountname = $_.samaccountname
            oldmobile = $_.mobile
            intermediate = $regexedmobile

            newmobile = if ($regexedmobile.StartsWith('353')) {
                            $regexedmobile -replace '^3530|^353','+353' -replace '^(\+353)(\d{3})(\d{3})(\d{3})', '$1 $2 $3 $4'
                        }
                        #Rep of Ireland missing leading prefix
                        elseif ($regexedmobile.StartsWith('08')) {
                            $regexedmobile -replace '^08','+3538' -replace '^(\+353)(\d{3})(\d{3})(\d{3})', '$1 $2 $3 $4'
                        }
                        #UK with missing leading '0'
                        elseif ($regexedmobile.StartsWith('7')) {
                            $regexedmobile -replace '^7','+447' -replace '^(\+44)(\d{4})(\d{3})(\d{3})', '$1 $2 $3 $4'
                        }
                        #India +91 International Dialling Code
                        elseif ($regexedmobile.StartsWith('91')) {
                            $regexedmobile -replace '^91','+91' -replace '^(\+91)(\d{4})(\d{3})(\d{3})', '$1 $2 $3 $4'
                        }
                        #Sri Lanka International Dialling Code
                        elseif ($regexedmobile.StartsWith('0094')) {
                            $regexedmobile -replace '^0094','+94' -replace '^(\+94)(\d{4})(\d{3})(\d{3})', '$1 $2 $3 $4'
                        }
                        #United States International Dialling Code
                        elseif ($regexedmobile.StartsWith('1')) {
                            $regexedmobile -replace '^1','+1' -replace '^(\+1)(\d{4})(\d{3})(\d{3})', '$1 $2 $3 $4'
                        }
                        #Everything else (should be UK)
                        else {
                            $regexedmobile -replace '^0|^4400|^440|^44','+44' -replace '^(\+44)(\d{4})(\d{3})(\d{3})', '$1 $2 $3 $4'
                        }
        }

        #If the users mobile field is not already populated then don't attempt to set a new mobile number.
        if ($null -ne $userobj.oldmobile) {
            Set-aduser -Identity $userobj.samaccountname -MobilePhone $userobj.newmobile -Credential $creds -Verbose -ErrorAction SilentlyContinue
        }

        #Return user object for validation
        $userobj

}