UIImagePickerController+Rx

class RxImagePickerDelegateProxy:
    DelegateProxy<UIImagePickerController, UIImagePickerControllerDelegate & UINavigationControllerDelegate>,
    DelegateProxyType,
    UIImagePickerControllerDelegate,
    UINavigationControllerDelegate {

    weak private(set) var imagePicker: UIImagePickerController?

    internal init(imagePicker: UIImagePickerController) {
        self.imagePicker = imagePicker
        super.init(parentObject: imagePicker, delegateProxy: RxImagePickerDelegateProxy.self)
    }

    static func registerKnownImplementations() {
        self.register(make: { RxImagePickerDelegateProxy(imagePicker: $0) })
    }

    static func currentDelegate(for object: UIImagePickerController) -> (UIImagePickerControllerDelegate & UINavigationControllerDelegate)? {
        return object.delegate
    }

    static func setCurrentDelegate(_ delegate: (UIImagePickerControllerDelegate & UINavigationControllerDelegate)?, to object: UIImagePickerController) {
        object.delegate = delegate
    }

}

extension Reactive where Base: UIImagePickerController {
    private var _delegate: DelegateProxy<UIImagePickerController, UIImagePickerControllerDelegate & UINavigationControllerDelegate> {
        return RxImagePickerDelegateProxy.proxy(for: base)
    }

    private var _selected: Observable<[String: Any]> {
        let selector = #selector(UIImagePickerControllerDelegate.imagePickerController(_:didFinishPickingMediaWithInfo:))
        return _delegate.methodInvoked(selector)
            .map({ (params) -> [String: Any] in
                return params[1] as! [String: Any]
            })
    }

    var cancel: Observable<Void> {
        return _delegate.methodInvoked(#selector(UIImagePickerControllerDelegate.imagePickerControllerDidCancel(_:)))
            .map({ _ in })
    }

    var selectedEditedImage: Observable<UIImage> {
        return _selected
            .map({ $0[UIImagePickerControllerEditedImage] as! UIImage })
    }

    var selectedOriginalImage: Observable<UIImage> {
        return _selected
            .map({ $0[UIImagePickerControllerOriginalImage] as! UIImage })
    }
}