Add base skeleton

moneymgr_mobile/lib/services/auth_state.dart

@@ -0,0 +1,75 @@
+import 'package:moneymgr_mobile/routes/login/login_model.dart';
+import 'package:moneymgr_mobile/services/router/routes_list.dart';
+import 'package:moneymgr_mobile/services/storage/secure_storage.dart';
+import 'package:riverpod_annotation/riverpod_annotation.dart';
+
+part 'auth_state.g.dart';
+
+/// The current authentication state of the app.
+///
+/// This notifier is responsible for saving/removing the token and profile info
+/// to the storage through the [login] and [logout] methods.
+@riverpod
+class CurrentAuthState extends _$CurrentAuthState {
+  @override
+  AuthState build() {
+    final secureStorage = ref.watch(secureStorageProvider).requireValue;
+    final token = secureStorage.get('token');
+    return token != null ? AuthState.authenticated : AuthState.unauthenticated;
+  }
+
+  /// Attempts to log in with [data] and saves the token and profile info to storage.
+  /// Will invalidate the state if success.
+  Future<void> login(LoginModel data) async {
+    // TODO : perform login
+    /*final secureStorage = ref.read(secureStorageProvider).requireValue;
+    final token = await ref.read(apiServiceProvider).login(data);
+
+    // Save the new [token] and [profile] to secure storage.
+    secureStorage.set('token', token);
+
+    ref
+    // Invalidate the state so the auth state will be updated to authenticated.
+      ..invalidateSelf()
+    // Invalidate the token provider so the API service will use the new token.
+      ..invalidate(tokenProvider);*/
+  }
+
+  /// Logs out, deletes the saved token and profile info from storage, and invalidates
+  /// the state.
+  void logout() {
+    // TODO : implement logic
+    /*final secureStorage = ref.read(secureStorageProvider).requireValue;
+
+    // Delete the current [token] and [profile] from secure storage.
+    secureStorage.remove('token');
+
+    ref
+    // Invalidate the state so the auth state will be updated to unauthenticated.
+      ..invalidateSelf()
+    // Invalidate the token provider so the API service will no longer use the
+    // previous token.
+      ..invalidate(tokenProvider);*/
+  }
+}
+
+
+/// The possible authentication states of the app.
+enum AuthState {
+  unknown(redirectPath: homePath, allowedPaths: [homePath]),
+  unauthenticated(
+    redirectPath: authPath,
+    allowedPaths: [authPath, settingsPath],
+  ),
+  authenticated(redirectPath: homePath, allowedPaths: null);
+
+  const AuthState({required this.redirectPath, required this.allowedPaths});
+
+  /// The target path to redirect when the current route is not allowed in this
+  /// auth state.
+  final String redirectPath;
+
+  /// List of paths allowed when the app is in this auth state. May be set to null if there is no
+  /// restriction applicable
+  final List<String>? allowedPaths;
+}