In-App Purchase (#718)

* Create encrypted file for In-App Purchases product identifiers

* Retrieve store products via IAPProductsService

* Synchronize fetchProducts(productIdentifiers:)

* Fix param name

* Validate receipts

* Add payments service

* Buy course

* Support course purchases API APPS-2768

* Update validate receipt method signature

* Cache ongoing payments

* Update product ids

* Use course payment payload data

* Add default course payment request handler

* Fix fetch course in default handler

* Add error descriptions

* Handle payment states in course info

* Present course info in course list on paid course click

* Fetch IAP localized price

* Prefetch products on app launch

* Clean up

* Merge Core Data models

* Update product ids

Author: ivan-magda

.gitattributes

@@ -4,6 +4,8 @@ StepicTests/TestInfo.plist filter=git-crypt diff=git-crypt
 Stepic/Auth.plist filter=git-crypt diff=git-crypt
 Stepic/GoogleService-Info.plist filter=git-crypt diff=git-crypt
 Stepic/Legacy/Model/Tokens/Tokens.plist filter=git-crypt diff=git-crypt
+Stepic/Sources/Frameworks/InAppPurchases/IAPProductIDs.plist filter=git-crypt diff=git-crypt
+Stepic/Sources/Frameworks/InAppPurchases/IAPPaymentsCache.swift filter=git-crypt diff=git-crypt
 fastlane/metadata/**/review_information/** filter=git-crypt diff=git-crypt
 fastlane/Deliverfile filter=git-crypt diff=git-crypt
 fastlane/Appfile filter=git-crypt diff=git-crypt

Stepic.xcodeproj/project.pbxproj

@@ -123,6 +123,8 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
 
         ApplicationThemeService().registerDefaultTheme()
 
+        IAPService.shared.startObservingPayments()
+
         return true
     }
 
@@ -137,13 +139,18 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
         NotificationsBadgesManager.shared.set(number: application.applicationIconBadgeNumber)
         self.notificationsService.removeRetentionNotifications()
         self.userCoursesObserver.startObserving()
+        IAPService.shared.prefetchProducts()
     }
 
     func applicationWillResignActive(_ application: UIApplication) {
         self.notificationsService.scheduleRetentionNotifications()
         self.userCoursesObserver.stopObserving()
     }
 
+    func applicationWillTerminate(_ application: UIApplication) {
+        IAPService.shared.stopObservingPayments()
+    }
+
     // MARK: - Downloading Data in the Background
 
     func application(

Stepic/Legacy/AppDelegate.swift

@@ -54,6 +54,7 @@ extension Course {
 
     @NSManaged var managedIsPaid: NSNumber?
     @NSManaged var managedDisplayPrice: String?
+    @NSManaged var managedPriceTier: NSNumber?
 
     // MARK: Relationships
     @NSManaged var managedAuthors: NSOrderedSet?
@@ -66,6 +67,7 @@ extension Course {
     @NSManaged var managedReviewSummary: CourseReviewSummary?
     @NSManaged var managedSections: NSOrderedSet?
     @NSManaged var managedUserCourse: UserCourse?
+    @NSManaged var managedCoursePurchases: NSOrderedSet?
 
     static var oldEntity: NSEntityDescription {
         NSEntityDescription.entity(forEntityName: "Course", in: CoreDataHelper.shared.context)!
@@ -256,6 +258,15 @@ extension Course {
         }
     }
 
+    var priceTier: Int? {
+        get {
+            self.managedPriceTier?.intValue
+        }
+        set {
+            self.managedPriceTier = newValue as NSNumber?
+        }
+    }
+
     var readiness: Float? {
         set {
             self.managedReadiness = newValue as NSNumber?
@@ -490,6 +501,19 @@ extension Course {
         }
     }
 
+    var purchases: [CoursePurchase] {
+        get {
+            (self.managedCoursePurchases?.array as? [CoursePurchase]) ?? []
+        }
+        set {
+            self.managedCoursePurchases = NSOrderedSet(array: newValue)
+        }
+    }
+
+    var isPurchased: Bool {
+        self.purchases.contains(where: { $0.isActive })
+    }
+
     var userCourse: UserCourse? {
         get {
             self.managedUserCourse

Stepic/Legacy/Model/Entities/Course/Course+CoreDataProperties.swift

@@ -120,6 +120,7 @@ final class Course: NSManagedObject, IDFetchable {
         self.languageCode = json[JSONKey.language.rawValue].stringValue
         self.isPaid = json[JSONKey.isPaid.rawValue].boolValue
         self.displayPrice = json[JSONKey.displayPrice.rawValue].string
+        self.priceTier = json[JSONKey.priceTier.rawValue].int
 
         self.certificate = json[JSONKey.certificate.rawValue].stringValue
         self.certificateRegularThreshold = json[JSONKey.certificateRegularThreshold.rawValue].int
@@ -436,5 +437,6 @@ final class Course: NSManagedObject, IDFetchable {
         case isPaid = "is_paid"
         case displayPrice = "display_price"
         case introVideo = "intro_video"
+        case priceTier = "price_tier"
     }
 }

Stepic/Legacy/Model/Entities/Course/Course.swift

@@ -0,0 +1,82 @@
+import CoreData
+import Foundation
+
+extension CoursePurchase {
+    @NSManaged var managedId: NSNumber?
+    @NSManaged var managedUserId: NSNumber?
+    @NSManaged var managedCourseId: NSNumber?
+    @NSManaged var managedIsActive: NSNumber?
+    @NSManaged var managedPaymentId: NSNumber?
+
+    @NSManaged var managedCourse: Course?
+
+    static var oldEntity: NSEntityDescription {
+        NSEntityDescription.entity(forEntityName: "CoursePurchase", in: CoreDataHelper.shared.context)!
+    }
+
+    static var defaultSortDescriptors: [NSSortDescriptor] {
+        [NSSortDescriptor(key: #keyPath(managedId), ascending: false)]
+    }
+
+    static var fetchRequest: NSFetchRequest<CoursePurchase> {
+        NSFetchRequest<CoursePurchase>(entityName: "CoursePurchase")
+    }
+
+    convenience init() {
+        self.init(entity: Self.oldEntity, insertInto: CoreDataHelper.shared.context)
+    }
+
+    var id: Int {
+        get {
+            self.managedId?.intValue ?? 0
+        }
+        set {
+            self.managedId = NSNumber(value: newValue)
+        }
+    }
+
+    var userID: Int {
+        get {
+            self.managedUserId?.intValue ?? 0
+        }
+        set {
+            self.managedUserId = NSNumber(value: newValue)
+        }
+    }
+
+    var courseID: Int {
+        get {
+            self.managedCourseId?.intValue ?? 0
+        }
+        set {
+            self.managedCourseId = NSNumber(value: newValue)
+        }
+    }
+
+    var isActive: Bool {
+        get {
+            self.managedIsActive?.boolValue ?? false
+        }
+        set {
+            self.managedIsActive = NSNumber(value: newValue)
+        }
+    }
+
+    var paymentID: Int {
+        get {
+            self.managedPaymentId?.intValue ?? 0
+        }
+        set {
+            self.managedPaymentId = NSNumber(value: newValue)
+        }
+    }
+
+    var course: Course? {
+        get {
+            self.managedCourse
+        }
+        set {
+            self.managedCourse = newValue
+        }
+    }
+}

Stepic/Legacy/Model/Entities/CoursePurchase/CoursePurchase+CoreDataProperties.swift

@@ -0,0 +1,32 @@
+import CoreData
+import Foundation
+import SwiftyJSON
+
+final class CoursePurchase: NSManagedObject, JSONSerializable, IDFetchable {
+    typealias IdType = Int
+
+    required convenience init(json: JSON) {
+        self.init()
+        self.update(json: json)
+    }
+
+    func update(json: JSON) {
+        self.id = json[JSONKey.id.rawValue].intValue
+        self.userID = json[JSONKey.user.rawValue].intValue
+        self.courseID = json[JSONKey.course.rawValue].intValue
+        self.isActive = json[JSONKey.isActive.rawValue].boolValue
+        self.paymentID = json[JSONKey.payment.rawValue].intValue
+    }
+
+    func hasEqualId(json: JSON) -> Bool {
+        self.id == json[JSONKey.id.rawValue].int
+    }
+
+    enum JSONKey: String {
+        case id
+        case user
+        case course
+        case isActive = "is_active"
+        case payment
+    }
+}

Stepic/Legacy/Model/Entities/CoursePurchase/CoursePurchase.swift

@@ -3,6 +3,6 @@
 <plist version="1.0">
 <dict>
 	<key>_XCCurrentVersionName</key>
-	<string>Model_new_profile_v53.xcdatamodel</string>
+	<string>Model_course_purchases_v54.xcdatamodel</string>
 </dict>
 </plist>