Get AzVMHybridUseBenefitCandidate

<#
.SYNOPSIS
    Identifies Windows VMs that are NOT using the Azure Hybrid Benefit (AHB).

.DESCRIPTION
    <!-- library-status:start -->
    Prüfstatus: Ungeprüft
    Windows- und Tenant-Abnahme ausstehend; keine pauschale Produktionsfreigabe.

    <!-- library-status:end -->

    Running Windows Server in Azure is cheaper if you bring your own license (AHB).
    This script finds VMs with 'Windows' OS where LicenseType is null or not 'Windows_Server',
    indicating potential cost savings.

.NOTES
    File Name  : 121_Get-AzVMHybridUseBenefitCandidate.ps1
    Author     : Kaffeeundcode
    Version    : 1.0
#>

try {
    Connect-AzAccount -ErrorAction Stop
} catch {
    Write-Error "Login failed. Run Connect-AzAccount."
    exit
}

Write-Host "Scanning VMs for Hybrid Benefit status..." -ForegroundColor Cyan
$VMs = Get-AzVM -Status

$Report = @()

foreach ($VM in $VMs) {
    # Check if OS is Windows
    if ($VM.StorageProfile.OsDisk.OsType -eq "Windows") {

        $LicenseType = $VM.LicenseType
        $Status = "Using AHB"

        if ([string]::IsNullOrWhiteSpace($LicenseType)) {
            $Status = "NOT Using AHB (Cost saving opportunity)"
        }

        $obj = [PSCustomObject]@{
            VMName = $VM.Name
            ResourceGroup = $VM.ResourceGroupName
            Size = $VM.HardwareProfile.VmSize
            LicenseType = if ($LicenseType) { $LicenseType } else { "PAYG (None)" }
            Status = $Status
        }
        $Report += $obj
    }
}

$Report | Sort-Object Status | Format-Table VMName, Size, LicenseType, Status -AutoSize

$Path = "$PSScriptRootAHB_Candidate_Report.csv"
$Report | Export-Csv -Path $Path -NoTypeInformation
Write-Host "Report saved to $Path" -ForegroundColor Green