BLEManager.swift

//
//  BLEPeripheral.swift
//  BLEPublishTest
//
//  Created by Paul Wilkinson on 22/4/20.
//  Copyright © 2020 Paul Wilkinson. All rights reserved.
//

    import Foundation
    import CoreBluetooth


    class BLEPeripheral: NSObject, CBPeripheralManagerDelegate, CBCentralManagerDelegate, CBPeripheralDelegate {
        
        
        
        static let shared = BLEPeripheral()
        
        var peripheralManager: CBPeripheralManager
        var centralManager: CBCentralManager
        private let beaconOperationsQueue = DispatchQueue(label: "beacon_operations_queue")
        private var peripheralName: String?
        private var connectTarget: CBPeripheral?
        
        
        let kTRANSFER_SERVICE_UUID  = "29ada058-c7d6-4ed5-bc7f-1c7b0458b3b8"
        let kTRANSFER_CHARACTERISTIC_UUID = "91e032f2-c915-47c6-a8d9-6b3bc6c8e73d"
        
        override init() {
            self.peripheralManager = CBPeripheralManager(delegate: nil, queue: beaconOperationsQueue, options: nil)
            self.centralManager = CBCentralManager()
            super.init()
            
            self.peripheralManager.delegate = self
            self.centralManager.delegate = self
        }
        
        public func startAdvertising(serviceID: CBUUID, name: String) {
            
            let valueData = name.data(using: .utf8)

            self.peripheralName = name
            
            let CustomChar = CBMutableCharacteristic(type: CBUUID(string: kTRANSFER_CHARACTERISTIC_UUID), properties: [.read], value: valueData, permissions: [.readable])
            
            let myService = CBMutableService(type:  serviceID, primary: true)
            myService.characteristics = [CustomChar]
            
            peripheralManager.add(myService)
            
            peripheralManager.startAdvertising([
                CBAdvertisementDataServiceUUIDsKey: [serviceID],CBAdvertisementDataLocalNameKey: peripheralName!])
        }
        
        func startScan() {
            self.centralManager.scanForPeripherals(withServices: [CBUUID(string:kTRANSFER_SERVICE_UUID)], options: nil)
        }
        
        func peripheralManagerDidUpdateState(_ peripheral: CBPeripheralManager) {
            if peripheral.state == .poweredOn {
                print("Powered on, start advertising")
                self.startAdvertising(serviceID: CBUUID(string:self.kTRANSFER_SERVICE_UUID), name: "Test")
            }
        }
        
        func centralManagerDidUpdateState(_ central: CBCentralManager) {
            if central.state == .poweredOn {
                print("Powered on, start scanning")
                self.startScan()
            }
        }
        
       public func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) {
             print("Discovered \(peripheral)")
        self.connectTarget = peripheral
        central.connect(peripheral)
        }
        
        
        public func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) {
            print("Connected to \(peripheral)")
            peripheral.delegate = self
            peripheral.discoverServices([CBUUID(string:kTRANSFER_SERVICE_UUID)])
        }
        
        func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {
        
            for service in peripheral.services ?? [] {
                print(service)
            }
        }
    }