ViewController.swift

import UIKit
import CoreBluetooth

class ViewController: UIViewController, CBCentralManagerDelegate, CBPeripheralManagerDelegate {
    
    var centralManager:CBCentralManager!
    var peripheralManager:CBPeripheralManager = CBPeripheralManager()
    let uuid:CBUUID = CBUUID(string: "DCEF54A2-31EB-467F-AF8E-350FB641C97B")

    override func viewDidLoad() {
        super.viewDidLoad()
        self.peripheralManager = CBPeripheralManager(delegate: self, queue: nil)
        self.centralManager = CBCentralManager(delegate: self, queue: nil)
        let advertisingData = [CBAdvertisementDataLocalNameKey:"my-peripheral", CBAdvertisementDataServiceUUIDsKey: uuid]
        peripheralManager.startAdvertising(advertisingData)
        centralManager.scanForPeripheralsWithServices([uuid], options: [ CBCentralManagerScanOptionAllowDuplicatesKey : true])
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    func peripheralManagerDidStartAdvertising(peripheral: CBPeripheralManager, error: NSError?) {
        print("started advertising")
        print(peripheral)
    }
    
    func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber) {
        print("peripheral discovered")
        print("peripheral: \(peripheral)")
        print("advertisement: \(advertisementData)")
        if let data = advertisementData["kCBAdvDataServiceData"] {
            print("found advert data: \(data)")
        }
        print("RSSI: \(RSSI)")
    }
    
    func centralManager(central: CBCentralManager, didDisconnectPeripheral peripheral: CBPeripheral, error: NSError?) {
        print("peripheral disconnected")
        print("peripheral: \(peripheral)")
    }
    
    func centralManagerDidUpdateState(central: CBCentralManager) {
        print("central state updated")
        print(central.description)
        if central.state == .PoweredOff {
            print("bluetooth is off")
        }
        if central.state == .PoweredOn {
            print("bluetooth is on")
            centralManager.scanForPeripheralsWithServices(nil, options: [ CBCentralManagerScanOptionAllowDuplicatesKey : true])
        }
        if central.state == .Unsupported {
            print("bluetooth is unsupported on this device")
        }
    }
    
    func peripheralManagerDidUpdateState(peripheral: CBPeripheralManager) {
        print("peripheral state updated")
        print("\(peripheral.description)")
    }

}