Virtualization App Capabilities (macOS 26/27)

import Virtualization
import Foundation

// MARK: - macOS Guest Provisioning (new in macOS 26)

func startProvisionedMacVM(virtualMachine: VZVirtualMachine) async throws {
    // 1. Build provisioning options for the first boot
    let provisioningOptions = VZMacGuestProvisioningOptions()
    provisioningOptions.fullName = "Jane Appleseed"
    provisioningOptions.userName = "jappleseed"
    provisioningOptions.password = ProcessInfo.processInfo.environment["VM_PASSWORD"] ?? "changeme"
    provisioningOptions.isAutoLoginEnabled = true
    provisioningOptions.isRemoteLoginEnabled = true   // enables SSH

    // 2. Attach provisioning options to start options
    let startOptions = VZMacOSVirtualMachineStartOptions()
    startOptions.guestProvisioning = provisioningOptions

    // 3. Start the VM — Setup Assistant will run headlessly on first boot
    try await virtualMachine.start(options: startOptions)
    print("VM started; guest will auto-provision user '\(provisioningOptions.userName)'")
}

// MARK: - Minimal VM configuration helper (macOS guest)

func buildMinimalMacVMConfiguration(bundleURL: URL) throws -> VZVirtualMachineConfiguration {
    let config = VZVirtualMachineConfiguration()

    // Load auxiliary storage created during macOS installation
    let auxStorageURL = bundleURL.appendingPathComponent("AuxiliaryStorage")
    let macPlatform = VZMacPlatformConfiguration()
    macPlatform.auxiliaryStorage = try VZMacAuxiliaryStorage(contentsOf: auxStorageURL)

    // Load hardware model & machine identifier saved at install time
    let hwModelData = try Data(contentsOf: bundleURL.appendingPathComponent("HardwareModel"))
    macPlatform.hardwareModel = VZMacHardwareModel(dataRepresentation: hwModelData)!
    let machineIDData = try Data(contentsOf: bundleURL.appendingPathComponent("MachineIdentifier"))
    macPlatform.machineIdentifier = VZMacMachineIdentifier(dataRepresentation: machineIDData)!
    config.platform = macPlatform

    // Boot loader
    config.bootLoader = VZMacOSBootLoader()

    // CPU & memory
    config.cpuCount = 4
    config.memorySize = 8 * 1024 * 1024 * 1024  // 8 GB

    // Disk
    let diskURL = bundleURL.appendingPathComponent("Disk.img")
    let diskAttachment = try VZDiskImageStorageDeviceAttachment(url: diskURL, readOnly: false)
    config.storageDevices = [VZVirtioBlockDeviceConfiguration(attachment: diskAttachment)]

    // Network (basic NAT)
    let networkDevice = VZVirtioNetworkDeviceConfiguration()
    networkDevice.attachment = VZNATNetworkDeviceAttachment()
    config.networkDevices = [networkDevice]

    try config.validate()
    return config
}

// MARK: - Usage example

func runDemo() async {
    let bundleURL = URL(fileURLWithPath: "/Users/me/VMs/MyMac.bundle")
    do {
        let config = try buildMinimalMacVMConfiguration(bundleURL: bundleURL)
        let vm = VZVirtualMachine(configuration: config)
        try await startProvisionedMacVM(virtualMachine: vm)
    } catch {
        print("VM provisioning failed: \(error)")
    }
}