fix(apple): show "Loading Resources..." instead of "No Resources" while loading (#6358)

Closes #6356

---------

Signed-off-by: Reactor Scram <ReactorScram@users.noreply.github.com>
Co-authored-by: Thomas Eizinger <thomas@eizinger.io>

swift/apple/FirezoneKit/Sources/FirezoneKit/Managers/TunnelManager.swift

@@ -82,7 +82,7 @@ public class TunnelManager {
 
   // Cache resources on this side of the IPC barrier so we can
   // return them to callers when they haven't changed.
-  private var resourcesListCache: [Resource] = []
+  private var resourcesListCache: ResourceList = ResourceList.loading
 
   // Persists our tunnel settings
   private var manager: NETunnelProviderManager?
@@ -272,7 +272,7 @@ public class TunnelManager {
     updateDisabledResources()
   }
 
-  func fetchResources(callback: @escaping ([Resource]) -> Void) {
+  func fetchResources(callback: @escaping (ResourceList) -> Void) {
     guard session().status == .connected else { return }
 
     do {
@@ -281,7 +281,7 @@ public class TunnelManager {
           self.resourceListHash = Data(SHA256.hash(data: data))
           let decoder = JSONDecoder()
           decoder.keyDecodingStrategy = .convertFromSnakeCase
-          self.resourcesListCache = (try? decoder.decode([Resource].self, from: data)) ?? []
+          self.resourcesListCache = ResourceList.loaded(try! decoder.decode([Resource].self, from: data))
         }
 
         callback(self.resourcesListCache)
@@ -323,7 +323,7 @@ public class TunnelManager {
           if session.status == .disconnected {
             // Reset resource list on disconnect
             resourceListHash = Data()
-            resourcesListCache = []
+            resourcesListCache = ResourceList.loading
           }
 
           await statusChangeHandler?(session.status)

swift/apple/FirezoneKit/Sources/FirezoneKit/Models/Resource.swift

@@ -8,6 +8,20 @@
 
 import Foundation
 
+public enum ResourceList {
+  case loading
+  case loaded([Resource])
+
+  public func asArray() -> [Resource] {
+    switch self {
+    case .loading:
+      []
+    case .loaded(let x):
+      x
+    }
+  }
+}
+
 public struct Resource: Decodable, Identifiable, Equatable {
   public let id: String
   public var name: String

swift/apple/FirezoneKit/Sources/FirezoneKit/Stores/Store.swift

@@ -142,7 +142,7 @@ public final class Store: ObservableObject {
 
   // Network Extensions don't have a 2-way binding up to the GUI process,
   // so we need to periodically ask the tunnel process for them.
-  func beginUpdatingResources(callback: @escaping ([Resource]) -> Void) {
+  func beginUpdatingResources(callback: @escaping (ResourceList) -> Void) {
     Log.app.log("\(#function)")
 
     tunnelManager.fetchResources(callback: callback)

swift/apple/FirezoneKit/Sources/FirezoneKit/Views/MenuBar.swift

@@ -18,7 +18,6 @@ import SwiftUI
 // https://developer.apple.com/documentation/swiftui/menubarextra
 public final class MenuBar: NSObject, ObservableObject {
   private var statusItem: NSStatusItem
-  private var resources: [Resource] = []
 
   // Wish these could be `[String]` but diffing between different types is tricky
   private var lastShownFavorites: [Resource] = []
@@ -73,20 +72,18 @@ public final class MenuBar: NSObject, ObservableObject {
 
         if status == .connected {
           model.store.beginUpdatingResources { newResources in
-              // Handle resource changes
-              self.populateResourceMenus(newResources)
-              self.handleTunnelStatusOrResourcesChanged(status: status, resources: newResources)
-              self.resources = newResources
+            // Handle resource changes
+            self.populateResourceMenus(newResources.asArray())
+            self.handleTunnelStatusOrResourcesChanged(status: status, resources: newResources)
           }
         } else {
           model.store.endUpdatingResources()
           populateResourceMenus([])
-          resources = []
         }
 
         // Handle status changes
         self.updateStatusItemIcon(status: status)
-        self.handleTunnelStatusOrResourcesChanged(status: status, resources: resources)
+        self.handleTunnelStatusOrResourcesChanged(status: status, resources: model.resources)
 
       }).store(in: &cancellables)
   }
@@ -325,7 +322,7 @@ public final class MenuBar: NSObject, ObservableObject {
     (connectingAnimationImageIndex + 1) % connectingAnimationImages.count
   }
 
-  private func handleTunnelStatusOrResourcesChanged(status: NEVPNStatus, resources: [Resource]?) {
+  private func handleTunnelStatusOrResourcesChanged(status: NEVPNStatus, resources: ResourceList) {
     // Update "Sign In" / "Sign Out" menu items
     switch status {
     case .invalid:
@@ -405,13 +402,16 @@ public final class MenuBar: NSObject, ObservableObject {
     }()
   }
 
-  private func resourceMenuTitle(_ resources: [Resource]?) -> String {
-    guard let resources = resources else { return "Loading Resources..." }
-
-    if resources.isEmpty {
-      return "No Resources"
-    } else {
-      return "Resources"
+  private func resourceMenuTitle(_ resources: ResourceList) -> String {
+    switch resources {
+    case .loading:
+      return "Loading Resources..."
+    case .loaded(let x):
+      if x.isEmpty {
+        return "No Resources"
+      } else {
+        return "Resources"
+      }
     }
   }
 
@@ -654,7 +654,7 @@ public final class MenuBar: NSObject, ObservableObject {
     // When the user clicks to add or remove a favorite, the menu will close anyway, so just recreate the whole menu.
     // This avoids complex logic when changing in and out of the "nothing is favorited" special case
     self.populateResourceMenus([])
-    self.populateResourceMenus(resources)
+    self.populateResourceMenus(model.resources.asArray())
   }
 
   private func copyToClipboard(_ string: String) {

swift/apple/FirezoneKit/Sources/FirezoneKit/Views/SessionView.swift

@@ -12,7 +12,7 @@ import SwiftUI
 @MainActor
 public final class SessionViewModel: ObservableObject {
   @Published private(set) var actorName: String? = nil
-  @Published private(set) var resources: [Resource]? = nil
+  @Published private(set) var resources: ResourceList = ResourceList.loading
   @Published private(set) var status: NEVPNStatus? = nil
 
 
@@ -67,7 +67,8 @@ struct SessionView: View {
   var body: some View {
     switch model.status {
     case .connected:
-      if let resources = model.resources {
+      switch model.resources {
+      case .loaded(let resources):
         if resources.isEmpty {
           Text("No Resources. Contact your admin to be granted access.")
         } else {
@@ -91,10 +92,9 @@ struct SessionView: View {
                 .navigationTitle("All Resources")
             }
           }
-
           .listStyle(GroupedListStyle())
         }
-      } else {
+      case .loading:
         Text("Loading Resources...")
       }
     case .connecting: