public void Book(int carId, DateTime start, DateTime end)
{
var car = _carRepository.FindById(carId);
if (car == null)
{
throw new CarDoesNotExistsException(carId);
}
var bookings = _bookingRepository.GetBooking(car, start, end);
if (bookings.Count > 0)
{
throw new CarIsAlreadyBookedException(carId, start, end);
}
var days = (int)Math.Ceiling((end - start).TotalDays);
_bookingRepository.BookCar(car, start, end, car.Price.DailyPrice * days);
}