Next step button

Stepic/Sources/Modules/NewLesson/NewLessonViewController.swift

@@ -255,14 +255,16 @@ final class NewLessonViewController: TabmanViewController, ControllerWithStepikP
         // Can navigate to previous unit from current step
         let canNavigateToPreviousUnit = index == 0 && hasNavigationToPreviousUnit
         let canNavigateToNextUnit = (index == self.stepModulesInputs.count - 1) && hasNavigationToNextUnit
+        let canNavigateToNextStep = index != self.stepModulesInputs.count - 1
 
         guard let input = self.stepModulesInputs[safe: index].flatMap({ $0 }) else {
             return
         }
 
         input.updateStepNavigation(
             canNavigateToPreviousUnit: canNavigateToPreviousUnit,
-            canNavigateNextUnit: canNavigateToNextUnit
+            canNavigateToNextUnit: canNavigateToNextUnit,
+            canNavigateToNextStep: canNavigateToNextStep
         )
     }
 

Stepic/Sources/Modules/NewStep/InputOutput/NewStepInputProtocol.swift

@@ -1,5 +1,5 @@
 import Foundation
 
 protocol NewStepInputProtocol: class {
-    func updateStepNavigation(canNavigateToPreviousUnit: Bool, canNavigateNextUnit: Bool)
+    func updateStepNavigation(canNavigateToPreviousUnit: Bool, canNavigateToNextUnit: Bool, canNavigateToNextStep: Bool)
 }

Stepic/Sources/Modules/NewStep/NewStepDataFlow.swift

@@ -19,11 +19,13 @@ enum NewStep {
         struct Response {
             let canNavigateToPreviousUnit: Bool
             let canNavigateToNextUnit: Bool
+            let canNavigateToNextStep: Bool
         }
 
         struct ViewModel {
             let canNavigateToPreviousUnit: Bool
             let canNavigateToNextUnit: Bool
+            let canNavigateToNextStep: Bool
         }
     }
 
@@ -51,8 +53,13 @@ enum NewStep {
 
     /// Handle navigation inside lesson
     enum StepNavigationRequest {
+        enum Direction {
+            case index(Int)
+            case next
+        }
+
         struct Request {
-            let index: Int
+            let direction: Direction
         }
     }
 

Stepic/Sources/Modules/NewStep/NewStepInteractor.swift

@@ -18,6 +18,9 @@ final class NewStepInteractor: NewStepInteractorProtocol {
     private let stepID: Step.IdType
     private var didAnalyticsSend = false
 
+    /// Current step index inside lesson.
+    private var currentStepIndex: Int?
+
     init(
         stepID: Step.IdType,
         presenter: NewStepPresenterProtocol,
@@ -35,6 +38,8 @@ final class NewStepInteractor: NewStepInteractorProtocol {
                 throw Error.fetchFailed
             }
 
+            self.currentStepIndex = step.position - 1
+
             DispatchQueue.main.async { [weak self] in
                 self?.presenter.presentStep(response: .init(result: .success(step)))
             }
@@ -79,7 +84,16 @@ final class NewStepInteractor: NewStepInteractorProtocol {
     }
 
     func doStepNavigationRequest(request: NewStep.StepNavigationRequest.Request) {
-        self.moduleOutput?.handleStepNavigation(to: request.index - 1)
+        switch request.direction {
+        case .index(let stepIndex):
+            self.moduleOutput?.handleStepNavigation(to: stepIndex)
+        case .next:
+            guard let currentStepIndex = self.currentStepIndex else {
+                return
+            }
+
+            self.moduleOutput?.handleStepNavigation(to: currentStepIndex + 1)
+        }
     }
 
     func doLessonNavigationRequest(request: NewStep.LessonNavigationRequest.Request) {
@@ -105,11 +119,16 @@ final class NewStepInteractor: NewStepInteractorProtocol {
 }
 
 extension NewStepInteractor: NewStepInputProtocol {
-    func updateStepNavigation(canNavigateToPreviousUnit: Bool, canNavigateNextUnit: Bool) {
+    func updateStepNavigation(
+        canNavigateToPreviousUnit: Bool,
+        canNavigateToNextUnit: Bool,
+        canNavigateToNextStep: Bool
+    ) {
         self.presenter.presentControlsUpdate(
             response: .init(
                 canNavigateToPreviousUnit: canNavigateToPreviousUnit,
-                canNavigateToNextUnit: canNavigateNextUnit
+                canNavigateToNextUnit: canNavigateToNextUnit,
+                canNavigateToNextStep: canNavigateToNextStep
             )
         )
     }

Stepic/Sources/Modules/NewStep/NewStepPresenter.swift

@@ -30,7 +30,8 @@ final class NewStepPresenter: NewStepPresenterProtocol {
     func presentControlsUpdate(response: NewStep.ControlsUpdate.Response) {
         let viewModel = NewStep.ControlsUpdate.ViewModel(
             canNavigateToPreviousUnit: response.canNavigateToPreviousUnit,
-            canNavigateToNextUnit: response.canNavigateToNextUnit
+            canNavigateToNextUnit: response.canNavigateToNextUnit,
+            canNavigateToNextStep: response.canNavigateToNextStep
         )
 
         self.viewController?.displayControlsUpdate(viewModel: viewModel)

Stepic/Sources/Modules/NewStep/NewStepViewController.swift

@@ -26,6 +26,8 @@ final class NewStepViewController: UIViewController, ControllerWithStepikPlaceho
 
     private var isFirstAppearance = true
 
+    private var canNavigateToNextStep = false
+
     init(interactor: NewStepInteractorProtocol) {
         self.interactor = interactor
         self.state = .loading
@@ -168,7 +170,11 @@ final class NewStepViewController: UIViewController, ControllerWithStepikPlaceho
         let quizController: UIViewController? = {
             switch quizType {
             case .string, .number, .math, .freeAnswer, .choice, .code, .sorting, .matching:
-                let assembly = BaseQuizAssembly(step: viewModel.step, output: self)
+                let assembly = BaseQuizAssembly(
+                    step: viewModel.step,
+                    hasNextStep: self.canNavigateToNextStep,
+                    output: self
+                )
                 return assembly.makeModule()
             default:
                 return initQuizController(type: quizType, step: viewModel.step)
@@ -197,6 +203,7 @@ extension NewStepViewController: NewStepViewControllerProtocol {
             hasPreviousButton: viewModel.canNavigateToPreviousUnit,
             hasNextButton: viewModel.canNavigateToNextUnit
         )
+        self.canNavigateToNextStep = viewModel.canNavigateToNextStep
     }
 }
 
@@ -251,7 +258,7 @@ extension NewStepViewController: NewStepViewDelegate {
                 if index + 1 < components.count {
                     let urlStepIndexString = components[index + 1]
                     if let urlStepIndex = Int(urlStepIndexString) {
-                        self.interactor.doStepNavigationRequest(request: .init(index: urlStepIndex))
+                        self.interactor.doStepNavigationRequest(request: .init(direction: .index(urlStepIndex - 1)))
                         return
                     }
                 }
@@ -287,4 +294,8 @@ extension NewStepViewController: BaseQuizOutputProtocol {
     func handleCorrectSubmission() {
         self.interactor.doStepDoneRequest(request: .init())
     }
+
+    func handleNextStepNavigation() {
+        self.interactor.doStepNavigationRequest(request: .init(direction: .next))
+    }
 }

Stepic/Sources/Modules/Quizzes/BaseQuiz/BaseQuizAssembly.swift

@@ -3,10 +3,12 @@ import UIKit
 final class BaseQuizAssembly: Assembly {
     private weak var moduleOutput: BaseQuizOutputProtocol?
     private let step: Step
+    private let hasNextStep: Bool
 
-    init(step: Step, output: BaseQuizOutputProtocol? = nil) {
+    init(step: Step, hasNextStep: Bool = false, output: BaseQuizOutputProtocol? = nil) {
         self.moduleOutput = output
         self.step = step
+        self.hasNextStep = hasNextStep
     }
 
     func makeModule() -> UIViewController {
@@ -18,6 +20,7 @@ final class BaseQuizAssembly: Assembly {
         let presenter = BaseQuizPresenter()
         let interactor = BaseQuizInteractor(
             step: self.step,
+            hasNextStep: self.hasNextStep,
             presenter: presenter,
             provider: provider,
             notificationSuggestionManager: NotificationSuggestionManager(),

Stepic/Sources/Modules/Quizzes/BaseQuiz/BaseQuizDataFlow.swift

@@ -9,6 +9,7 @@ enum BaseQuiz {
             let submission: Submission?
             let cachedReply: Reply?
             let submissionsCount: Int
+            let hasNextStep: Bool
         }
 
         struct Request {
@@ -56,6 +57,11 @@ enum BaseQuiz {
         }
     }
 
+    /// Navigate to next step  inside lesson
+    enum NextStepNavigation {
+        struct Request { }
+    }
+
     enum ViewControllerState {
         case loading
         case result(data: BaseQuizViewModel)

Stepic/Sources/Modules/Quizzes/BaseQuiz/BaseQuizInteractor.swift

@@ -5,6 +5,7 @@ protocol BaseQuizInteractorProtocol {
     func doSubmissionLoad(request: BaseQuiz.SubmissionLoad.Request)
     func doSubmissionSubmit(request: BaseQuiz.SubmissionSubmit.Request)
     func doReplyCache(request: BaseQuiz.ReplyCache.Request)
+    func doNextStepNavigationRequest(request: BaseQuiz.NextStepNavigation.Request)
 }
 
 final class BaseQuizInteractor: BaseQuizInteractorProtocol {
@@ -21,19 +22,22 @@ final class BaseQuizInteractor: BaseQuizInteractorProtocol {
     private let rateAppManager: RateAppManager
 
     let step: Step
+    private let hasNextStep: Bool
 
     private var submissionsCount = 0
     private var currentAttempt: Attempt?
 
     init(
         step: Step,
+        hasNextStep: Bool,
         presenter: BaseQuizPresenterProtocol,
         provider: BaseQuizProviderProtocol,
         notificationSuggestionManager: NotificationSuggestionManager,
         rateAppManager: RateAppManager,
         userService: UserAccountServiceProtocol
     ) {
         self.step = step
+        self.hasNextStep = hasNextStep
         self.presenter = presenter
         self.provider = provider
         self.userService = userService
@@ -147,6 +151,10 @@ final class BaseQuizInteractor: BaseQuizInteractorProtocol {
         }
     }
 
+    func doNextStepNavigationRequest(request: BaseQuiz.NextStepNavigation.Request) {
+        self.moduleOutput?.handleNextStepNavigation()
+    }
+
     // MARK: - Private API
 
     @discardableResult
@@ -186,7 +194,8 @@ final class BaseQuizInteractor: BaseQuizInteractorProtocol {
             attempt: attempt,
             submission: submission,
             cachedReply: cachedReply,
-            submissionsCount: self.submissionsCount
+            submissionsCount: self.submissionsCount,
+            hasNextStep: self.hasNextStep
         )
 
         self.presenter.presentSubmission(response: .init(result: .success(response)))

Stepic/Sources/Modules/Quizzes/BaseQuiz/BaseQuizOutputProtocol.swift

@@ -2,4 +2,5 @@ import Foundation
 
 protocol BaseQuizOutputProtocol: class {
     func handleCorrectSubmission()
+    func handleNextStepNavigation()
 }

Stepic/Sources/Modules/Quizzes/BaseQuiz/BaseQuizPresenter.swift

@@ -19,7 +19,8 @@ final class BaseQuizPresenter: BaseQuizPresenterProtocol {
                 submission: data.submission,
                 attempt: data.attempt,
                 cachedReply: data.cachedReply,
-                submissionsCount: data.submissionsCount
+                submissionsCount: data.submissionsCount,
+                hasNextStep: data.hasNextStep
             )
             self.viewController?.displaySubmission(viewModel: .init(state: .result(data: viewModel)))
         }
@@ -38,7 +39,8 @@ final class BaseQuizPresenter: BaseQuizPresenterProtocol {
         submission: Submission?,
         attempt: Attempt,
         cachedReply: Reply?,
-        submissionsCount: Int
+        submissionsCount: Int,
+        hasNextStep: Bool
     ) -> BaseQuizViewModel {
         let quizStatus: QuizStatus? = {
             guard let submission = submission else {
@@ -90,6 +92,8 @@ final class BaseQuizPresenter: BaseQuizPresenterProtocol {
 
         let isSubmitButtonDisabled = quizStatus == .evaluation || submissionsLeft == 0
         let shouldPassPeerReview = quizStatus == .correct && step.hasReview
+        let canNavigateToNextStep = quizStatus == .correct && hasNextStep
+        let canRetry = quizStatus == .correct && !(submissionsLeft == 0)
 
         let hintContent: String? = {
             if let text = submission?.hint, !text.isEmpty {
@@ -122,7 +126,9 @@ final class BaseQuizPresenter: BaseQuizPresenterProtocol {
             shouldPassPeerReview: shouldPassPeerReview,
             stepURL: self.makeURL(for: step),
             hintContent: hintContent,
-            codeDetails: codeDetails
+            codeDetails: codeDetails,
+            canNavigateToNextStep: canNavigateToNextStep,
+            canRetry: canRetry
         )
     }