bt.swift

//
//  BTConnectionHandler.swift
//  AdTableTest
//
//  Created by Paul Wilkinson on 24/06/2016.
//  Copyright © 2016 Paul Wilkinson. All rights reserved.
//

import Foundation
import CoreBluetooth

class BTConnectionHandler: NSObject, CBPeripheralManagerDelegate {
    
    var cbManager: CBPeripheralManager!
    
    var serialService: CBMutableService!
    var advertisementData: [String: AnyObject]!
    var tx: CBMutableCharacteristic!
    var rx: CBMutableCharacteristic!
    
    let TX_UUID = CBUUID(string: "68A36B42-DE0D-452E-9A5B-E2655CB73163")
    let TX_PROPERTIES: CBCharacteristicProperties = [.read, .notify]
    let TX_PERMISSIONS: CBAttributePermissions = .readable
    
    let RX_UUID = CBUUID(string: "3B66D024-2336-4F22-A980-8095F4898C42")
    let RX_PROPERTIES: CBCharacteristicProperties = .write
    let RX_PERMISSIONS: CBAttributePermissions = .writeable
    
    let SERIAL_UUID = CBUUID(string: "81F02411-BAD8-4367-8EE0-710FFA610608")
    
    var receiveQueue = [NSData]();
    
    override init() {
        
        super.init()
        
        self.cbManager = CBPeripheralManager(delegate: self, queue: nil)
        
        // cbManager.startAdvertising(ADVERTISEMENT_DATA)
        
        self.serialService = CBMutableService(type: SERIAL_UUID, primary: true)
        self.tx = CBMutableCharacteristic(type: TX_UUID, properties: TX_PROPERTIES, value: nil, permissions: TX_PERMISSIONS)
        self.rx = CBMutableCharacteristic(type: RX_UUID, properties: RX_PROPERTIES, value: nil, permissions: RX_PERMISSIONS)
        self.serialService.characteristics = [tx,rx]
        
        
    }
    
    
    
    // CENTRAL read from TX
    func peripheralManager(_ peripheral: CBPeripheralManager, didReceiveRead request: CBATTRequest) {
        print("Read request received from central device")
        request.value = tx.value
        self.cbManager.respond(to: request, withResult: .success)
    }
    
    // CENTRAL write to RX
    func peripheralManager(_ peripheral: CBPeripheralManager, didReceiveWrite requests: [CBATTRequest]) {
        print("Write request(s) received from central device")
        for request in requests {
            if let value = request.value {
                
                DispatchQueue.global(attributes: .qosUtility).sync { ()-> Void in
                    self.receiveQueue.append(value)
                }
            }
            self.cbManager.respond(to: request, withResult: .success)
        }
    }
    
    func startAdvertising() {
        
        self.advertisementData = [CBAdvertisementDataLocalNameKey: "serialThingy", CBAdvertisementDataServiceUUIDsKey: [SERIAL_UUID]]
        
        self.cbManager.add(self.serialService)
        self.cbManager.startAdvertising(advertisementData)
        
    }
    
    func stopAdvertising() {
        self.cbManager.remove(self.serialService)
        self.cbManager.stopAdvertising()
    }
    
    // Print state of peripheral manager as it changes
    func peripheralManagerDidUpdateState(_ peripheral:CBPeripheralManager) {
        
        
        switch peripheral.state {
        case .poweredOn:
            print("Bluetooth is powered on")
            startAdvertising()
        case .poweredOff:
            stopAdvertising()
        default:
            print("Bluetooth state is \(peripheral.state.rawValue)")
        }
        
    }
    
    func getReceivedData() -> NSData? {
        var returnData: NSData? = nil
        DispatchQueue.global(attributes: .qosUtility).sync { ()-> Void in
            if (self.receiveQueue.count > 0) {
                returnData = self.receiveQueue.removeFirst()
            }
        }
        return returnData
    }
    
    
}