AccessorySetupKit

import AccessorySetupKit
import CoreBluetooth

var descriptor = ASDiscoveryDescriptor()
descriptor.bluetoothServiceUUID = CBUUID(string: "12345678-1234-1234-1234-123456789ABC")
descriptor.bluetoothNameSubstring = "MyDevice"
descriptor.bluetoothRange = .immediate  // Only nearby devices

var descriptor = ASDiscoveryDescriptor()
descriptor.ssid = "MyAccessory-Network"
// OR use a prefix:
// descriptor.ssidPrefix = "MyAccessory-"

descriptor.supportedOptions = [.bluetoothPairingLE, .bluetoothTransportBridging]

import AccessorySetupKit

final class AccessoryManager {
    private let session = ASAccessorySession()

    func start() {
        session.activate(on: .main) { [weak self] event in
            self?.handleEvent(event)
        }
    }

    private func handleEvent(_ event: ASAccessoryEvent) {
        switch event.eventType {
        case .activated:
            // Session ready. Check session.accessories for previously paired devices.
            break
        case .accessoryAdded:
            guard let accessory = event.accessory else { return }
            handleAccessoryAdded(accessory)
        case .accessoryChanged:
            // Accessory properties changed (e.g., display name updated in Settings)
            break
        case .accessoryRemoved:
            // Accessory removed by user or app
            break
        case .invalidated:
            // Session invalidated, cannot be reused
            break
        default:
            break
        }
    }
}

func showAccessoryPicker() {
    var descriptor = ASDiscoveryDescriptor()
    descriptor.bluetoothServiceUUID = CBUUID(string: "ABCD1234-0000-1000-8000-00805F9B34FB")

    guard let image = UIImage(named: "my-accessory") else { return }

    let item = ASPickerDisplayItem(
        name: "My Bluetooth Accessory",
        productImage: image,
        descriptor: descriptor
    )

    session.showPicker(for: [item]) { error in
        if let error {
            print("Picker failed: \(error.localizedDescription)")
        }
    }
}

var item = ASPickerDisplayItem(
    name: "My Accessory",
    productImage: image,
    descriptor: descriptor
)
item.setupOptions = [.rename, .confirmAuthorization]

private var pendingAccessory: ASAccessory?

private func handleEvent(_ event: ASAccessoryEvent) {
    switch event.eventType {
    case .accessoryAdded:
        pendingAccessory = event.accessory
    case .pickerDidDismiss:
        if let accessory = pendingAccessory {
            pendingAccessory = nil
            beginCustomSetup(accessory)
        }
    default:
        break
    }
}

import CoreBluetooth

func handleAccessoryAdded(_ accessory: ASAccessory) {
    guard let btIdentifier = accessory.bluetoothIdentifier else { return }

    // Create CBCentralManager — no Bluetooth permission prompt appears
    let centralManager = CBCentralManager(delegate: self, queue: nil)

    // After poweredOn, retrieve the peripheral
    let peripherals = centralManager.retrievePeripherals(
        withIdentifiers: [btIdentifier]
    )
    guard let peripheral = peripherals.first else { return }
    centralManager.connect(peripheral, options: nil)
}

import NetworkExtension

func handleWiFiAccessoryAdded(_ accessory: ASAccessory) {
    guard let ssid = accessory.ssid else { return }

    let configuration = NEHotspotConfiguration(ssid: ssid)
    NEHotspotConfigurationManager.shared.apply(configuration) { error in
        if let error {
            print("Wi-Fi join failed: \(error.localizedDescription)")
        }
    }
}

func migrateExistingAccessories() {
    guard let image = UIImage(named: "my-accessory") else { return }

    var descriptor = ASDiscoveryDescriptor()
    descriptor.bluetoothServiceUUID = CBUUID(string: "ABCD1234-0000-1000-8000-00805F9B34FB")

    let migrationItem = ASMigrationDisplayItem(
        name: "My Accessory",
        productImage: image,
        descriptor: descriptor
    )
    // Set the peripheral identifier from CoreBluetooth
    migrationItem.peripheralIdentifier = existingPeripheralUUID

    // For Wi-Fi accessories:
    // migrationItem.hotspotSSID = "MyAccessory-WiFi"

    session.showPicker(for: [migrationItem]) { error in
        if let error {
            print("Migration failed: \(error.localizedDescription)")
        }
    }
}

// WRONG — service UUID not in NSAccessorySetupBluetoothServices
var descriptor = ASDiscoveryDescriptor()
descriptor.bluetoothServiceUUID = CBUUID(string: "UNDECLARED-UUID")
session.showPicker(for: [item]) { _ in }  // Crash

// CORRECT — declare all UUIDs in Info.plist first
// Info.plist: NSAccessorySetupBluetoothServices = ["ABCD1234-..."]
var descriptor = ASDiscoveryDescriptor()
descriptor.bluetoothServiceUUID = CBUUID(string: "ABCD1234-...")

// WRONG — crashes at runtime
var descriptor = ASDiscoveryDescriptor()
descriptor.ssid = "MyNetwork"
descriptor.ssidPrefix = "My"  // Cannot set both

// CORRECT — use one or the other
var descriptor = ASDiscoveryDescriptor()
descriptor.ssid = "MyNetwork"

// WRONG — migration fails, picker does not appear
let central = CBCentralManager(delegate: self, queue: nil)
session.showPicker(for: [migrationItem]) { error in
    // error is non-nil
}

// CORRECT — wait for .migrationComplete before using CoreBluetooth
session.activate(on: .main) { event in
    if event.eventType == .migrationComplete {
        let central = CBCentralManager(delegate: self, queue: nil)
    }
}

// WRONG — picker appears unexpectedly on app launch
override func viewDidLoad() {
    super.viewDidLoad()
    session.showPicker(for: items) { _ in }
}

// CORRECT — bind picker to a user action
@IBAction func addAccessoryTapped(_ sender: UIButton) {
    session.showPicker(for: items) { _ in }
}

// WRONG — session is dead after invalidation
session.showPicker(for: items) { _ in }  // No effect

// CORRECT — create a new session
let newSession = ASAccessorySession()
newSession.activate(on: .main) { event in
    // Handle events
}