Persist "Only favorites" toggle (#813)

Drop didChange subjects from filters model, observe published fields
directly.

Passepartout/Library/Sources/AppUIMain/Views/Provider/VPNFiltersView+Model.swift

@@ -24,6 +24,7 @@
 //
 
 import Combine
+import CommonLibrary
 import Foundation
 import PassepartoutKit
 
@@ -33,6 +34,8 @@ extension VPNFiltersView {
     final class Model: ObservableObject {
         typealias CodeWithDescription = (code: String, description: String)
 
+        private let defaults: UserDefaults
+
         private var options: VPNFilterOptions
 
         @Published
@@ -45,22 +48,21 @@ extension VPNFiltersView {
         private(set) var presets: [AnyVPNPreset]
 
         @Published
-        var filters = VPNFilters()
+        var filters: VPNFilters
 
         @Published
-        var onlyShowsFavorites = false
-
-        let filtersDidChange = PassthroughSubject<VPNFilters, Never>()
-
-        let onlyShowsFavoritesDidChange = PassthroughSubject<Bool, Never>()
+        var onlyShowsFavorites: Bool
 
         private var subscriptions: Set<AnyCancellable>
 
-        init() {
+        init(defaults: UserDefaults = .standard) {
+            self.defaults = defaults
             options = VPNFilterOptions()
             categories = []
             countries = []
             presets = []
+            filters = VPNFilters()
+            onlyShowsFavorites = false
             subscriptions = []
 
             observeObjects()
@@ -129,22 +131,31 @@ private extension VPNFiltersView.Model {
 
 private extension VPNFiltersView.Model {
     func observeObjects() {
-        $filters
+        $onlyShowsFavorites
+            .dropFirst()
             .sink { [weak self] in
-                self?.filtersDidChange.send($0)
+                self?.defaults.onlyShowsFavorites = $0
             }
             .store(in: &subscriptions)
 
-        $onlyShowsFavorites
-            .sink { [weak self] in
-                self?.onlyShowsFavoritesDidChange.send($0)
-            }
-            .store(in: &subscriptions)
+        // send initial value
+        onlyShowsFavorites = defaults.onlyShowsFavorites
     }
 }
 
 // MARK: -
 
+private extension UserDefaults {
+    var onlyShowsFavorites: Bool {
+        get {
+            bool(forKey: AppPreference.onlyShowsFavorites.key)
+        }
+        set {
+            set(newValue, forKey: AppPreference.onlyShowsFavorites.key)
+        }
+    }
+}
+
 private extension String {
     var asCountryCodeWithDescription: VPNFiltersView.Model.CodeWithDescription {
         (self, localizedAsRegionCode ?? self)

Passepartout/Library/Sources/AppUIMain/Views/Provider/VPNProviderServerView.swift

@@ -166,12 +166,12 @@ extension VPNProviderServerView {
                     errorHandler.handle(error, title: Strings.Global.servers)
                 }
             }
-            .onReceive(filtersViewModel.filtersDidChange) { newValue in
+            .onReceive(filtersViewModel.$filters) { newValue in
                 Task {
                     await reloadServers(filters: newValue)
                 }
             }
-            .onReceive(filtersViewModel.onlyShowsFavoritesDidChange) { newValue in
+            .onReceive(filtersViewModel.$onlyShowsFavorites) { newValue in
                 onlyShowsFavorites = newValue
             }
             .onDisappear {

Passepartout/Library/Sources/CommonLibrary/Domain/AppPreference.swift

@@ -32,6 +32,8 @@ public enum AppPreference: String {
 
     case logsPrivateData
 
+    case onlyShowsFavorites
+
     case profilesLayout
 
     case providerFavoriteServers