#!/snap/bin/powershell

# Syntax:       ./check-ipv4-address.ps1 [<address>]
# Description:	checks the given IPv4 address for validity
# Author:	Markus Fleschutz
# Source:	github.com/fleschutz/PowerShell
# License:	CC0

param([string]$Addr)

# IPv4-Address like 192.168.178.1
$RegEx = "^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$"

try {
	if ($Addr -eq "" ) {
		$Addr = read-host "Enter IPv4 address to validate"
	}
	if ($Addr -match $RegEx) {
		write-output "IPv4 address $Addr is valid"
		exit 0
	} else {
		write-output "IPv4 address $Addr is NOT valid"
		exit 1
	}
} catch {
	write-error "ERROR in line $($_.InvocationInfo.ScriptLineNumber): $($Error[0])"
	exit 1
}