Nagios - SQL Backup check

declare @tgt varchar(128)
declare @uts varchar(16)
declare @output varchar(128)
select @uts = DATEDIFF(s, '1970-01-01 00:00:00', SYSUTCDATETIME() )
set @tgt = 'D:\SQL_Data\backup.status'
set @output = 'echo ' + @uts + ' > ' + @tgt
exec master..xp_cmdshell @output

# args: path, warnhours, crithours
If ($Args.count -lt 3) {
  write-output "UNKNOWN: Too few parameters!"
  exit 3
}

If ($Args[1] -eq "$" -Or $Args[2] -eq "$") {
  write-output "UNKNOWN: Warning and critical must be set!"
  exit 3
}

If (!$Args[0] -Or !$Args[1] -Or !$Args[2]) {
  write-output "UNKNOWN: Three arguments needed!"
  exit 3
}

Function Convert-FromUnixdate ($UnixDate) {
   [timezone]::CurrentTimeZone.ToLocalTime(([datetime]'1/1/1970').`
   AddSeconds($UnixDate))
}

$arg_file = $Args[0]
$arg_warn_hours = $Args[1]
$arg_crit_hours = $Args[2]

If (![System.IO.File]::Exists($arg_file)) {
  write-output "UNKNOWN: File $arg_file does not exist!"
  exit 3
}

If ($arg_warn_hours -ge $arg_crit_hours) {
  write-output "UNKNOWN: Warning can't be bigger than critical"
  exit 3
}

$tsfile = Get-Content $arg_file
$nicefile = Convert-FromUnixDate $tsfile

$tsnow = [int][double]::Parse($(Get-Date -date (Get-Date).ToUniversalTime()-uformat %s))
# DEBUG $nicetime = Convert-FromUnixDate $tsnow
# DEBUG write-output "NOW $tsnow - $nicetime"

$tswarnlimit = [int]$tsfile + [int]($arg_warn_hours * 3600)
$tscritlimit = [int]$tsfile + [int]($arg_crit_hours * 3600)

If ( $tscritlimit -le $tsnow ) {
  write-output "CRITICAL: Last backup finished at $nicefile"
  exit 2
}
ElseIf ( $tswarnlimit -le $tsnow ) {
  write-output "WARNING: Last backup finished at $nicefile"
  exit 1
}
Else {
  write-output "OK: Last backup finished at $nicefile"
  exit 0
}

# If you want to fill this file with all avalible options run the following command:
#   nscp settings --generate --add-defaults --load-all
# If you want to activate a module and bring in all its options use:
#   nscp settings --activate-module <MODULE NAME> --add-defaults
# For details run: nscp settings --help


; Undocumented section
[/settings/default]

; Undocumented key
password = S1hD35Dqs3PxrR4A

; Undocumented key
allowed hosts = 127.0.0.1,172.16.0.47,::1


; Undocumented section
[/settings/NRPE/server]
allow arguments=true
allow nasty characters=true

; Undocumented key
verify mode = none

; Undocumented key
insecure = true


; Undocumented section
[/modules]

; Undocumented key
CheckExternalScripts = 1

; Undocumented key
CheckHelpers = 1

; Undocumented key
CheckEventLog = 1

; Undocumented key
CheckNSCP = 1

; Undocumented key
CheckDisk = 1

; Undocumented key
CheckSystem = 1

; Undocumented key
NRPEServer = 1

; rss
[/settings/external scripts]
allow arguments=true
allow nasty characters=true

[/settings/external scripts/scripts]
check_backupstatus = cmd /c echo d:\sql_data\check_backupstatus.ps1 "$ARG1$" $ARG2$ $ARG3$ ; exit($lastexitcode) | powershell.exe -command -