CarFleetFeatureToggleLogic.swift

// MARK: - Toggle Logic For CarFleet

protocol CarFleetFeatureToggleLogic {
    var fuelToUse: Fuel { get }
    func transport(car: Car, to position: Position)
}

extension CarFleetFeatureToggleLogic where Self: CarFleet {
    /**
    Get the fuel to be used on cars.
    - Toggle Options:
        - Toggle on: return fuel type for rockets.
        - Toggle off: return fuel type for cars.
    */
    var fuelToUse: Fuel {
        switch Toggles.Vehicle.carsCanFly.enabled {
        case true  : Fuel.rocket
        case false : Fuel.car
        }
    }

    /**
    Transport cars to their destination.
    - Toggle Options:
        - Toggle on: Fly cars to destination.
        - Toggle off: Drive cars to destination.
    */
    func transport(car: Car, to position: Position) {
        switch Toggles.Vehicle.carsCanFly.enabled {
        case true  : fly(to: location)
        case false : drive(to: location)
        }
    }
}