Deprecate storing user data in UserDefaults (#574)

## Summary
Previously we were double-writing to CoreData and to UserDefaults in
case we decided not to move ahead with CoreData. Now we have a public
release that is fully migrated to CoreData we are committed to the
migration, and don't need to maintain the UserDefaults paths.

This leaves in the code which migrates data from UserDefaults to
CoreData, so it it still possible to seamlessly upgrade from previous
versions, but removes incremental updates to UserDefaults, and deletes
all values after the data has been migrated. This means downgrading from
this version to <6.7 will require logging in again.

## Validation
* [x] Launch the app and verify you can reload goals, view timezone
* [x] Verify it is still possible to seamlessly upgrade from code before
the CoreData migration

BeeKit/Managers/CurrentUserManager.swift

@@ -48,11 +48,13 @@ public actor CurrentUserManager {
 
     init(requestManager: RequestManager, container: BeeminderPersistentContainer) {
         self.requestManager = requestManager
-        modelContainer = container
+        self.modelContainer = container
         let context = container.newBackgroundContext()
         context.name = "CurrentUserManager"
-        modelExecutor = .init(context: context)
+        self.modelExecutor = .init(context: context)
+
         migrateValuesToCoreData()
+        cleanUpUserDefaults()
     }
 
     // If there is an existing session based on UserDefaults, create a new User object
@@ -69,7 +71,6 @@ public actor CurrentUserManager {
             return
         }
 
-
         // Create a new user
         let _ = User(context: context,
             username: userDefaults.object(forKey: CurrentUserManager.usernameKey) as! String,
@@ -82,6 +83,14 @@ public actor CurrentUserManager {
         try! context.save()
     }
 
+    private nonisolated func cleanUpUserDefaults() {
+        for key in CurrentUserManager.allKeys {
+            userDefaults.removeObject(forKey: key)
+        }
+    }
+
+
+    // MARK: - User Management
 
     public nonisolated func user(context: NSManagedObjectContext) -> User? {
         do {
@@ -94,11 +103,27 @@ public actor CurrentUserManager {
         }
     }
 
-    private func modifyUser(_ callback: (User)->()) throws {
+    public nonisolated func isDeadbeat(context: NSManagedObjectContext) -> Bool {
+        return user(context: context)?.deadbeat ?? false
+    }
+
+    public var username: String? {
+        return user(context: modelContext)?.username
+    }
+
+    public func refreshUser() async throws {
+        let response = try await requestManager.get(url: "api/v1/users/\(username!).json", parameters: [:])
+        let responseJSON = JSON(response!)
+
         guard let user = self.user(context: modelContext) else { return }
         modelContext.refresh(user, mergeChanges: false)
-        callback(user)
+        user.updateToMatch(json: responseJSON)
         try modelContext.save()
+
+        await Task { @MainActor in
+            guard let user = self.user(context: modelContainer.viewContext) else { return }
+            modelContainer.viewContext.refresh(user, mergeChanges: false)
+        }.value
     }
 
     private func deleteUser() throws {
@@ -110,38 +135,22 @@ public actor CurrentUserManager {
         try modelContext.save()
     }
 
-    /// Write a value to the UserDefaults store
-    ///
-    /// During migration to the appGroup shared store we still want to support users downgrading
-    /// to prior versions, and thus write all values to both stores.
-    func set(_ value: Any, forKey key: String) {
-        userDefaults.set(value, forKey: key)
-    }
-
-    func removeObject(forKey key: String) {
-        userDefaults.removeObject(forKey: key)
-    }
+    // MARK: - Keychain Management
 
-    public nonisolated var accessToken :String? {
-        return keychain.get(CurrentUserManager.accessTokenKey)
+    nonisolated func setAccessToken(_ accessToken: String) {
+        keychain.set(accessToken, forKey: CurrentUserManager.accessTokenKey, withAccess: .accessibleAfterFirstUnlock)
     }
 
-    public var username :String? {
-        return user(context: modelContext)?.username
+    public nonisolated var accessToken: String? {
+        return keychain.get(CurrentUserManager.accessTokenKey)
     }
 
+    // MARK: - Authentication
+
     public nonisolated func signedIn(context: NSManagedObjectContext) -> Bool {
         return self.accessToken != nil && self.user(context: context)?.username != nil
     }
 
-    public nonisolated func isDeadbeat(context: NSManagedObjectContext) -> Bool {
-        return user(context: context)?.deadbeat ?? false
-    }
-
-    nonisolated func setAccessToken(_ accessToken: String) {
-        keychain.set(accessToken, forKey: CurrentUserManager.accessTokenKey, withAccess: .accessibleAfterFirstUnlock)
-    }
-
     public func signInWithEmail(_ email: String, password: String) async {
         do {
             let response = try await requestManager.post(url: "api/private/sign_in", parameters: ["user": ["login": email, "password": password], "beemios_secret": self.beemiosSecret] as Dictionary<String, Any>)
@@ -157,42 +166,13 @@ public actor CurrentUserManager {
         let _ = User(context: modelContext, json: responseJSON)
         try modelContext.save()
 
-        if responseJSON["deadbeat"].boolValue {
-            self.set(true, forKey: CurrentUserManager.deadbeatKey)
-        } else {
-            self.removeObject(forKey: CurrentUserManager.deadbeatKey)
-        }
         self.setAccessToken(responseJSON[CurrentUserManager.accessTokenKey].string!)
-        self.set(responseJSON[CurrentUserManager.usernameKey].string!, forKey: CurrentUserManager.usernameKey)
-        self.set(responseJSON[CurrentUserManager.defaultAlertstartKey].number!, forKey: CurrentUserManager.defaultAlertstartKey)
-        self.set(responseJSON[CurrentUserManager.defaultDeadlineKey].number!, forKey: CurrentUserManager.defaultDeadlineKey)
-        self.set(responseJSON[CurrentUserManager.defaultLeadtimeKey].number!, forKey: CurrentUserManager.defaultLeadtimeKey)
-        self.set(responseJSON[CurrentUserManager.beemTZKey].string!, forKey: CurrentUserManager.beemTZKey)
+
         await Task { @MainActor in
             NotificationCenter.default.post(name: Notification.Name(rawValue: CurrentUserManager.signedInNotificationName), object: self)
         }.value
     }
 
-    public func refreshUser() async throws {
-        let response = try await requestManager.get(url: "api/v1/users/\(username!).json", parameters: [:])
-        let responseJSON = JSON(response!)
-
-        try! modifyUser { user in
-            user.updateToMatch(json: responseJSON)
-        }
-
-        self.set(responseJSON[CurrentUserManager.usernameKey].string!, forKey: CurrentUserManager.usernameKey)
-        self.set(responseJSON[CurrentUserManager.defaultAlertstartKey].number!, forKey: CurrentUserManager.defaultAlertstartKey)
-        self.set(responseJSON[CurrentUserManager.defaultDeadlineKey].number!, forKey: CurrentUserManager.defaultDeadlineKey)
-        self.set(responseJSON[CurrentUserManager.defaultLeadtimeKey].number!, forKey: CurrentUserManager.defaultLeadtimeKey)
-        self.set(responseJSON[CurrentUserManager.beemTZKey].string!, forKey: CurrentUserManager.beemTZKey)
-
-        await Task { @MainActor in
-            guard let user = self.user(context: modelContainer.viewContext) else { return }
-            modelContainer.viewContext.refresh(user, mergeChanges: false)
-        }.value
-    }
-
     func handleFailedSignin(_ responseError: Error, errorMessage : String?) async throws {
         await Task { @MainActor in
             NotificationCenter.default.post(name: Notification.Name(rawValue: CurrentUserManager.failedSignInNotificationName), object: self, userInfo: ["error" : responseError])
@@ -208,15 +188,9 @@ public actor CurrentUserManager {
         try deleteUser()
 
         keychain.delete(CurrentUserManager.accessTokenKey)
-        self.removeObject(forKey: CurrentUserManager.deadbeatKey)
-        self.removeObject(forKey: CurrentUserManager.usernameKey)
 
         await Task { @MainActor in
             NotificationCenter.default.post(name: Notification.Name(rawValue: CurrentUserManager.signedOutNotificationName), object: self)
         }.value
     }
-}
-
-public enum CurrentUserManagerError : Error {
-    case loggedOut
-}
+}