param(
  [string]$VMName,
  [string]$IP,
  [int]$MaskBits,
  [string]$Gateway,
  [string]$DNS,
  [string]$GuestUser,
  [string]$GuestPassword
)

$sec = ConvertTo-SecureString $GuestPassword -AsPlainText -Force
$cred = New-Object pscredential($GuestUser, $sec)

try {
  $vm = Get-VM -Name $VMName -ErrorAction Stop

  if ($vm.PowerState -ne 'PoweredOn') {
    [pscustomobject]@{ status="error"; message="VM is powered off" } | ConvertTo-Json
    exit
  }

  if ($vm.ExtensionData.Guest.ToolsStatus -notin @('toolsOk','toolsOld')) {
    [pscustomobject]@{ status="error"; message="VMware Tools not ready" } | ConvertTo-Json
    exit
  }

  $script = @"
`$adapter = Get-NetAdapter | Where-Object { `$_.Status -eq 'Up' } | Select-Object -First 1
Remove-NetIPAddress -InterfaceIndex `$adapter.ifIndex -Confirm:`$false -ErrorAction SilentlyContinue
Remove-NetRoute -InterfaceIndex `$adapter.ifIndex -Confirm:`$false -ErrorAction SilentlyContinue
New-NetIPAddress -InterfaceIndex `$adapter.ifIndex -IPAddress "$IP" -PrefixLength $MaskBits -DefaultGateway "$Gateway"
Set-DnsClientServerAddress -InterfaceIndex `$adapter.ifIndex -ServerAddresses "$DNS"
"@

  $res = Invoke-VMScript -VM $vm -ScriptText $script -GuestCredential $cred -ScriptType PowerShell

  [pscustomobject]@{
    status="ok"
    message="IP updated"
    ip=$IP
  } | ConvertTo-Json

} catch {
  [pscustomobject]@{
    status="error"
    message=$_.Exception.Message
  } | ConvertTo-Json
}