param(
    [object]$Config,
    [string]$LogFile
)

$ErrorActionPreference = "Continue"

function Write-Log {
    param([string]$Message, [string]$Level = "INFO")
    $line = "[$(Get-Date -Format 'HH:mm:ss')] [$Level] $Message"
    Add-Content -Path $LogFile -Value $line -Encoding UTF8
}

# -----------------------------------------------------------------------
# KMS Generic Volume License Keys (GVLK)
# Source: https://docs.microsoft.com/en-us/windows-server/get-started/kms-client-activation-keys
# These are official Microsoft-published keys for use with KMS infrastructure.
# Replace with your MAK/retail key for standalone activation.
# -----------------------------------------------------------------------
$KmsKeys = @{
    # Windows 11
    "Windows 11 Pro"                    = "W269N-WFGWX-YVC9B-4J6C9-T83GX"
    "Windows 11 Pro N"                  = "MH37W-N47XK-V7XM9-C7227-GCQG9"
    "Windows 11 Pro Education"          = "6TP4R-GNPTD-KYYHQ-7B7DP-J447Y"
    "Windows 11 Education"              = "NW6C2-QMPVW-D7KKK-3GKT6-VCFB2"
    "Windows 11 Enterprise"             = "NPPR9-FWDCX-D2C8J-H872K-2YT43"
    # Windows 10
    "Windows 10 Pro"                    = "W269N-WFGWX-YVC9B-4J6C9-T83GX"
    "Windows 10 Pro N"                  = "MH37W-N47XK-V7XM9-C7227-GCQG9"
    "Windows 10 Education"              = "NW6C2-QMPVW-D7KKK-3GKT6-VCFB2"
    "Windows 10 Enterprise"             = "NPPR9-FWDCX-D2C8J-H872K-2YT43"
    "Windows 10 Home"                   = "TX9XD-98N7V-6WMQ6-BX7FG-H8Q99"
}

# -----------------------------------------------------------------------
# Check current activation status
# -----------------------------------------------------------------------
Write-Log "Checking Windows activation status" -Level INFO

$licenseStatus = (Get-CimInstance SoftwareLicensingProduct -Filter "PartialProductKey IS NOT NULL AND Name LIKE 'Windows%'" -ErrorAction SilentlyContinue |
                  Select-Object -First 1).LicenseStatus
# LicenseStatus: 0=Unlicensed, 1=Licensed, 2=OOBGrace, 3=OOTGrace, 4=NonGenuineGrace, 5=Notification, 6=ExtendedGrace

if ($licenseStatus -eq 1) {
    Write-Log "  Windows is already activated - skipping" -Level OK
} else {
    Write-Log "  Activation status: $licenseStatus (not activated)" -Level WARN

    # Detect Windows edition
    $osCaption = (Get-CimInstance Win32_OperatingSystem -ErrorAction SilentlyContinue).Caption
    Write-Log "  Detected OS: $osCaption" -Level INFO

    # Check if a key is configured in config
    $customKey = $null
    if ($Config -and $Config.activation -and $Config.activation.productKey) {
        $customKey = $Config.activation.productKey
    }

    if ($customKey -and $customKey -ne "XXXXX-XXXXX-XXXXX-XXXXX-XXXXX") {
        # Use key from config
        $keyToUse = $customKey
        Write-Log "  Using product key from config" -Level INFO
    } else {
        # Find matching GVLK key by OS name
        $keyToUse = $null
        foreach ($entry in $KmsKeys.GetEnumerator()) {
            if ($osCaption -like "*$($entry.Key)*") {
                $keyToUse = $entry.Value
                Write-Log "  Matched GVLK key for: $($entry.Key)" -Level INFO
                break
            }
        }
    }

    if (-not $keyToUse) {
        Write-Log "  No matching key found for: $osCaption" -Level WARN
        Write-Log "  Skipping activation - set activation.productKey in config.json" -Level WARN
    } else {
        # Install key
        Write-Log "  Installing product key..." -Level INFO
        $ipkResult = & cscript //nologo "$env:SystemRoot\System32\slmgr.vbs" /ipk $keyToUse 2>&1
        if ($LASTEXITCODE -eq 0) {
            Write-Log "  Key installed" -Level OK
        } else {
            Write-Log "  Key install result: $ipkResult" -Level WARN
        }

        # Set KMS server if configured
        if ($Config -and $Config.activation -and $Config.activation.kmsServer) {
            $kmsServer = $Config.activation.kmsServer
            Write-Log "  Setting KMS server: $kmsServer" -Level INFO
            & cscript //nologo "$env:SystemRoot\System32\slmgr.vbs" /skms $kmsServer 2>&1 | Out-Null
        }

        # Attempt activation
        Write-Log "  Attempting activation..." -Level INFO
        $atoResult = & cscript //nologo "$env:SystemRoot\System32\slmgr.vbs" /ato 2>&1
        $atoOutput = $atoResult -join " "

        if ($atoOutput -match "successfully" -or $atoOutput -match "uspesn") {
            Write-Log "  Activation successful" -Level OK
        } else {
            Write-Log "  Activation result: $atoOutput" -Level WARN
            Write-Log "  Activation may require a KMS server or valid MAK key" -Level WARN
        }
    }
}

Write-Log "Step 8 - Activation complete" -Level OK