WinCloudInit.psm1

function Set-WinCloudInit {
    param(
        [switch] $Enabled,
        [ValidateRange(0,99)]
        [int] $State,
        [pscredential] $Credential
    )

    Set-Content $PSScriptRoot\state $State

    if ($PSBoundParameters.ContainsKey('Enabled')) {
        if ($Enabled) {
            Set-WinCloudInit -Enabled:$false
            if (-not $Credential) {
                $Credential = Get-Credential -UserName $env:USERNAME -Message 'Specify credential'
            }
            $user = $Credential.UserName
            $password = $Credential.GetNetworkCredential().Password
            $command = 'powershell -Command Start-WinCloudInit'
            schtasks /Create /TN 'WinCloudInit' /RU $user /RP $password /TR $command /SC ONSTART
        } else {
            if (schtasks | Select-String WinCloudInit) {
                schtasks /Delete /TN 'WinCloudInit' /F
            }
        }
    } elseif ($Credential.UserName -eq 'SYSTEM') {
        schtasks /Change /TN 'WinCloudInit' /RU 'SYSTEM'
    }
}

function Start-WinCloudInit {
    [CmdletBinding()]
    param()
    $Log = Join-Path C:\Windows\Temp "WinCloudInit-$((Get-Date).ToString('MM-dd-yy')).log"

    "Starting WinCloudInit $(Get-Date)" >> $Log
    'Searching for cloud-config.json on floppy/cdrom' >> $Log
    $Found = $false
    2,5 | % {
        if ($ConfigDrive = Get-CimInstance -ClassName Win32_LogicalDisk -Filter "DriveType = $_" -Property DeviceID) {
            $ConfigPath = Join-Path $ConfigDrive.DeviceID 'cloud-config.json'
            if (Test-Path $ConfigPath) { $Found = $ConfigPath; return }
        }
    }
    if (-not $Found) {
        'Searching for cloud-config.json on local drive' >> $Log
        $LocalPath = 'C:\WinCloudInit\cloud-config.json'
        if (Test-Path $LocalPath) { $Found = $LocalPath }
    }

    if ($Found) {
        "Found in $Found" >> $Log
        $Config = Get-Content $Found -Raw | ConvertFrom-Json |
        Add-Member -MemberType NoteProperty -Name _Path -Value (Split-Path $Found) -TypeName string -Force -PassThru
        mkdir C:\WinCloudInit\ -ea SilentlyContinue
        Copy-Item $Found "C:\WinCloudInit\_cloud-config.json" -Force
    } else {
        $Msg = 'No config source found'
        $Msg >> $Log
        throw $Msg
    }

    # state file contains last executed plugin number (for reboot handling)
    'Reading <state> file' >> $Log
    $StatePath = "$PSScriptRoot\state"
    try {
        if (-not (Test-Path $StatePath)) {
            New-Item -Path $StatePath -ItemType File
        }
        $State = [int](Get-Content $StatePath)
        "State is $State" >> $Log
    } catch {
        $Msg = 'Invalid state file content'
        $Msg >> $Log
        throw $Msg
    }

    'Running plugins:' >> $Log
    Get-ChildItem $PSScriptRoot\plugins | Sort Name |
    ? { ($_.Name.Split('-')[0] -as [int]) -gt $State } -pv Plugin | % {
        try {
            "Executing $($Plugin.Name)" >> $Log
            $Output = & $Plugin.FullName -Config $Config -Verbose 4>> $Log
        } catch {
            $Msg = "Error during $($Plugin.Name) execution"
            ($_ | Out-String) >> $Log
            throw $Msg
        }
        $Plugin.Name.Split('-')[0] > $StatePath
        if (($Output | Select -Last 1) -eq 'reboot') { break } # exit function, continue after reboot
    }
    
    'Disabling WinCloudInit' >> $Log
    Set-WinCloudInit -Enabled:$false
}