WordPress to Jetpack flow: main flow implementation

WordPress/Classes/System/WindowManager.swift

@@ -82,7 +82,7 @@ class WindowManager: NSObject {
     /// Shows the specified VC as the root VC for the managed window.  Takes care of animating the transition whenever the existing
     /// root VC isn't `nil` (this is because a `nil` VC means we're showing the initial VC on a call to this method).
     ///
-    func show(_ viewController: UIViewController, completion: Completion?) {
+    func show(_ viewController: UIViewController, completion: Completion? = nil) {
         // When the App is launched, the root VC will be `nil`.
         // When this is the case we'll simply show the VC without any type of animation.
         guard window.rootViewController != nil else {

WordPress/Jetpack/Classes/System/JetpackWindowManager.swift

@@ -1,10 +1,14 @@
+import Combine
 import Foundation
 
 class JetpackWindowManager: WindowManager {
+    /// receives migration flow updates in order to dismiss it when needed.
+    private var cancellable: AnyCancellable?
+
     override func showUI(for blog: Blog?) {
         // If the user is logged in and has blogs sync'd to their account
         if AccountHelper.isLoggedIn && AccountHelper.hasBlogs {
-            showAppUI(for: blog)
+            shouldShowMigrationUI ? showMigrationUI(blog) : showAppUI(for: blog)
             return
         }
 
@@ -18,4 +22,27 @@ class JetpackWindowManager: WindowManager {
         // the `logOutDefaultWordPressComAccount` method will trigger the `showSignInUI` automatically
         AccountHelper.logOutDefaultWordPressComAccount()
     }
+
+    private func showMigrationUI(_ blog: Blog?) {
+        let container = MigrationDependencyContainer()
+        cancellable = container.migrationCoordinator.$currentStep
+            .receive(on: DispatchQueue.main)
+            .sink { [weak self] step in
+                guard step == .dismiss else {
+                    return
+                }
+                self?.switchToAppUI(for: blog)
+            }
+        self.show(container.makeInitialViewController())
+    }
+
+    private func switchToAppUI(for blog: Blog?) {
+        cancellable = nil
+        showAppUI(for: blog)
+    }
+
+    // TODO: Add logic in here to trigger migration UI if needed
+    private var shouldShowMigrationUI: Bool {
+        false
+    }
 }

WordPress/Jetpack/Classes/ViewRelated/WordPress-to-Jetpack Migration/All done/MigrationDoneViewController.swift

@@ -0,0 +1,26 @@
+import UIKit
+
+class MigrationDoneViewController: UIViewController {
+
+    private let viewModel: MigrationDoneViewModel
+
+    init(viewModel: MigrationDoneViewModel) {
+        self.viewModel = viewModel
+        super.init(nibName: nil, bundle: nil)
+    }
+
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+
+    override func loadView() {
+        // TODO: replace this blank center view with the actual content
+        let centerView = UIView()
+        centerView.translatesAutoresizingMaskIntoConstraints = false
+        centerView.setContentHuggingPriority(UILayoutPriority.defaultLow, for: .vertical)
+
+        view = MigrationStepView(headerView: MigrationHeaderView(configuration: viewModel.configuration.headerConfiguration),
+                                 actionsView: MigrationActionsView(configuration: viewModel.configuration.actionsConfiguration),
+                                 centerView: centerView)
+    }
+}

WordPress/Jetpack/Classes/ViewRelated/WordPress-to-Jetpack Migration/All done/MigrationDoneViewModel.swift

@@ -0,0 +1,15 @@
+class MigrationDoneViewModel {
+
+    let configuration: MigrationStepConfiguration
+
+    init(coordinator: MigrationFlowCoordinator) {
+
+        let headerConfiguration = MigrationHeaderConfiguration(step: .done)
+
+        let actionsConfiguration = MigrationActionsViewConfiguration(step: .done, primaryHandler: { [weak coordinator] in
+            coordinator?.transitionToNextStep()
+        })
+        configuration = MigrationStepConfiguration(headerConfiguration: headerConfiguration,
+                                                   actionsConfiguration: actionsConfiguration)
+    }
+}

WordPress/Jetpack/Classes/ViewRelated/WordPress-to-Jetpack Migration/Common/MigrationDependencyContainer.swift

@@ -0,0 +1,70 @@
+struct MigrationDependencyContainer {
+
+    let migrationCoordinator = MigrationFlowCoordinator()
+
+    func makeInitialViewController() -> UIViewController {
+        MigrationNavigationController(coordinator: migrationCoordinator,
+                                      factory: MigrationViewControllerFactory(coordinator: migrationCoordinator))
+    }
+}
+
+struct MigrationViewControllerFactory {
+
+    let coordinator: MigrationFlowCoordinator
+
+    init(coordinator: MigrationFlowCoordinator) {
+        self.coordinator = coordinator
+    }
+
+    func viewController(for step: MigrationStep) -> UIViewController? {
+        switch step {
+        case .welcome:
+            return makeWelcomeViewController()
+        case .notifications:
+            return makeNotificationsViewController()
+        case .done:
+            return makeDoneViewController()
+        case .dismiss:
+            return nil
+        }
+    }
+
+    func initialViewController() -> UIViewController? {
+        viewController(for: coordinator.currentStep)
+    }
+
+    private func makeAccount() -> WPAccount? {
+
+        let context = ContextManager.shared.mainContext
+        do {
+            return try WPAccount.lookupDefaultWordPressComAccount(in: context)
+        } catch {
+            DDLogError("Account lookup failed with error: \(error)")
+            return nil
+        }
+    }
+
+    private func makeWelcomeViewModel() -> MigrationWelcomeViewModel {
+        MigrationWelcomeViewModel(account: makeAccount(), coordinator: coordinator)
+    }
+
+    private func makeWelcomeViewController() -> UIViewController {
+        MigrationWelcomeViewController(viewModel: makeWelcomeViewModel())
+    }
+
+    private func makeNotificationsViewModel() -> MigrationNotificationsViewModel {
+        MigrationNotificationsViewModel(coordinator: coordinator)
+    }
+
+    private func makeNotificationsViewController() -> UIViewController {
+        MigrationNotificationsViewController(viewModel: makeNotificationsViewModel())
+    }
+
+    private func makeDoneViewModel() -> MigrationDoneViewModel {
+        MigrationDoneViewModel(coordinator: coordinator)
+    }
+
+    private func makeDoneViewController() -> UIViewController {
+        MigrationDoneViewController(viewModel: makeDoneViewModel())
+    }
+}