CentralManagerDelegate.swift

/// Facade for the CBCentralManagerDelegate.
protocol CentralManagerDelegate: CBCentralManagerDelegate {
    /// Function called when the central manager updates its state.
    func centralManagerDidUpdateState(_ central: CentralManager)
    
    /// Function called when the central manager discovers peripherals.
    func centralManager(_ central: CentralManager,
                        didDiscover peripheral: Peripheral,
                        advertisementData: [String : Any],
                        rssi RSSI: NSNumber)
}

/// Wishful thinking... 
/// This is unfortunately not possible due to the inherited objective-c exposure requirement from the CBCentralManagerDelegate file.
extension CentralManagerDelegate {
    func centralManagerDidUpdateState(_ central: CBCentralManager) {
        centralManagerDidUpdateState(central as CentralManager)
    }
    
    func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) {
        centralManager(central as CentralManager,
                       didDiscover: peripheral as Peripheral,
                       advertisementData: advertisementData,
                       rssi: RSSI)
    }
}