@available(iOS 10.3, *)
open class SKStoreReviewController : NSObject {
    /** Request StoreKit to ask the user for an app review.
     *  This may or may not show any UI.
     *
     *  Given this may not succussfully present an alert to
     *  the user, it is not appropriate for use from a button
     *  or any other user action. For presenting a write
     *  review form, a deep link is available to the App
     *  Store by appending the query params
     *  "action=write-review" to a product URL.
     */
    open class func requestReview()
}

// BPOrderViewController

typedef enum : NSUInteger {
    BPOrderEntryContextFromDirectPayment,
    BPOrderEntryContextFromHistoryList,
    BPOrderEntryContextFromNotificationMessage,
    BPOrderEntryContextFromMerchantPayment,
} BPOrderEntryContext;

// BPOrderObject

- (BOOL)isFinalized
{
    return self.status == BPOrderObjectStatusCompleted || self.status == BPOrderObjectStatusCompleting;
}

guard
    isDirectPurchase && order.isFinalized(),
    giftIDs[order.orderID].map({ $0 != 0 }) ?? false
        || order.isWelcomeGift()
        || order.isDiscounted()
        || order.hasRebate(),
    isLoyalCustomer(dateFirstOpenedApp: dateFirstOpenedApp),
    !hasSeenPromptRecently(datelastReviewed: dateLastReviewed)
    else {
    return false
}

if !order.isFinalized() {
    return false
}
if !(isWelcomeGift(order: order)
    || order.isFreeGift()
    || order.isDiscounted()
    || order.hasRebate()) {
    return false
}
if !isLoyalCustomer() {
    return false
}
if hasSeenPromptRecently() {
    return false
}

let tutorial = TutorialKit(
    name: "tutorial-demo-example",
    makeSteps: { [weak self] in
        guard let this = self else {
            return []
        }
        return [
            TutorialStepText(target: this.label, text: "This is a text view"),
            TutorialStepText(
                target: CGRect(x: 100, y: 100, width: 100, height: 100),
                text: "This is an arbitrary frame"
            ),
            TutorialStepText(
                target: TutorialTargetTableViewCell(this.table, at: [0, 10]) {
                    return $0.detailTextLabel
                },
                text: "This is a table view cell's detail")
            )
        ]
    }
)

weakify(self);
_tutorial = [[TutorialKit alloc] initWithName:@"tutorial-kit-demo" makeSteps:^NSArray * {
    strongify(self);
    NSMutableArray *steps = [[NSMutableArray alloc] init];
    [steps addObject:[[TutorialStepText alloc]
                      initWithTarget:self.label
                      text:@"This is a text view"]];
    [steps addObject:[[TutorialStepText alloc]
                      initWithTarget: [[TutorialTargetCGRect alloc]
                                       init:CGRectMake(100, 100, 100, 100)]
                      text:@"This is an arbitrary frame"]];
    [steps addObject:[[TutorialStepText alloc]
                      initWithTarget: [[TutorialTargetTableViewCell alloc]
                                       init:self.table
                                       at: [NSIndexPath indexPathForRow:10 inSection:0]
                                       targetForCell:^UIView * (UITableViewCell *cell) {
                                           return cell.detailTextLabel;
                                       }]
                      text:@"This is a table view cell's detail"]];
    return steps;
}]

public class TutorialKit: NSObject {
    public init(name: String, makeSteps: @escaping () -> [TutorialStep]) { ... }

    @available(swift, obsoleted: 1.0)
    @objc public convenience init(name: String, makeSteps: @escaping () -> [Any]) { ... }

    @objc public func start() { ... }
    @objc public func forceStart() { ... }
    @objc public func hasSeenTutorial() -> Bool { ... }
}

public protocol TutorialStep {
    var target: UIView { get }

    var willEnter: (() -> Void)? { get set }
    var didEnter: (() -> Void)? { get set }
    var willExit: (() -> Void)? { get set }
    var didExit: (() -> Void)? { get set }

    /**
     Returns a UIView that should be shown when the step is displayed

     - Parameter frame: The frame the UIView should draw within
     - Parameter targetFrame: The frame of the view the step is targeting
     */
    func makeView(frame: CGRect, targetFrame: CGRect) -> UIView
}

public class TutorialStepPointing: NSObject, TutorialStep { ... }
public class TutorialStepText: TutorialStepPointing { ... }

+ public protocol TutorialTarget { ... }

  public protocol TutorialStep {
-     var target: UIView { get }
+     var target: TutorialTarget { get }

      var willEnter: (() -> Void)? { get set }
      var didEnter: (() -> Void)? { get set }
      var willExit: (() -> Void)? { get set }
      var didExit: (() -> Void)? { get set }

      /**
       Returns a UIView that should be shown when the step is displayed

       - Parameter frame: The frame the UIView should draw within
       - Parameter targetFrame: The frame of the view the step is targeting
       */
      func makeView(frame: CGRect, targetFrame: CGRect) -> UIView
  }

public protocol TutorialTarget {
    /**
     Will be called before the tutorial step is displayed

     - Important: This function should not be animated as it will be wrapped in a UIView.animate()

     - Parameter completion: should be called with the target rect after the target is in view
     */
    func scrollToFrame(completion: @escaping (CGRect) -> Void)
}

extension UIView: TutorialTarget { ... }
extension CGRect: TutorialTarget { ... }
public class TutorialTargetTableViewCell: NSObject, TutorialTarget { ... }
public class TutorialTargetCollectionViewCell: NSObject, TutorialTarget { ... }
@objc public class TutorialTargetCGRect: NSObject, TutorialTarget { ... }

public class TutorialTargetTableViewCell: NSObject, TutorialTarget {
    public init(_ collectionView: UICollectionView,
        at indexPath: IndexPath,
        targetForCell: @escaping (UICollectionViewCell) -> TutorialTarget? = { $0 })

    @available(swift, obsoleted: 1.0)
    @objc public convenience init(_ collectionView: UICollectionView,
        at indexPath: IndexPath,
        targetForCell: @escaping (UICollectionViewCell) -> Any? = { $0 })

    ...
}