First working version

ios/Runner/VPN/Helpers/Stored.swift

@@ -0,0 +1,86 @@
+//
+//  Stored.swift
+//  Runner
+//
+//  Created by GFWFighter on 10/24/23.
+//
+
+import Foundation
+import Combine
+
+enum StoredLocation {
+    case standard
+    
+    func data(for key: String) -> Data? {
+        switch self {
+        case .standard:
+            return UserDefaults.standard.data(forKey: key)
+        }
+    }
+    
+    func set(_ value: Data, for key: String) {
+        switch self {
+        case .standard:
+            UserDefaults.standard.set(value, forKey: key)
+        }
+    }
+}
+
+
+@propertyWrapper
+struct Stored<Value: Codable> {
+    let location: StoredLocation
+    let key: String
+    var wrappedValue: Value {
+        willSet {  // Before modifying wrappedValue
+            publisher.subject.send(newValue)
+            guard let value = try? JSONEncoder().encode(newValue) else {
+                return
+            }
+            location.set(value, for: key)
+        }
+    }
+
+    var projectedValue: Publisher {
+        publisher
+    }
+    private var publisher: Publisher
+    struct Publisher: Combine.Publisher {
+        typealias Output = Value
+        typealias Failure = Never
+        var subject: CurrentValueSubject<Value, Never> // PassthroughSubject will lack the call of initial assignment
+        func receive<S>(subscriber: S) where S: Subscriber, Self.Failure == S.Failure, Self.Output == S.Input {
+            subject.subscribe(subscriber)
+        }
+        init(_ output: Output) {
+            subject = .init(output)
+        }
+    }
+    init(wrappedValue: Value, key: String, in location: StoredLocation = .standard) {
+        self.location = location
+        self.key = key
+        var value = wrappedValue
+        if let data = location.data(for: key) {
+            do {
+                value = try JSONDecoder().decode(Value.self, from: data)
+            } catch {}
+        }
+        self.wrappedValue = value
+        publisher = Publisher(value)
+    }
+    static subscript<OuterSelf: ObservableObject>(
+        _enclosingInstance observed: OuterSelf,
+        wrapped wrappedKeyPath: ReferenceWritableKeyPath<OuterSelf, Value>,
+        storage storageKeyPath: ReferenceWritableKeyPath<OuterSelf, Self>
+    ) -> Value {
+        get {
+            observed[keyPath: storageKeyPath].wrappedValue
+        }
+        set {
+            if let subject = observed.objectWillChange as? ObservableObjectPublisher {
+                subject.send() // Before modifying wrappedValue
+                observed[keyPath: storageKeyPath].wrappedValue = newValue
+            }
+        }
+    }
+}

ios/Runner/VPN/VPNConfig.swift

@@ -0,0 +1,22 @@
+//
+//  VPNConfig.swift
+//  Runner
+//
+//  Created by GFWFighter on 10/24/23.
+//
+
+import Foundation
+import Combine
+
+class VPNConfig: ObservableObject {
+    static let shared = VPNConfig()
+    
+    @Stored(key: "VPN.ActiveConfigPath")
+    var activeConfigPath: String = ""
+    
+    @Stored(key: "VPN.ConfigOptions")
+    var configOptions: String = ""
+    
+    @Stored(key: "VPN.DisableMemoryLimit")
+    var disableMemoryLimit: Bool = false
+}

ios/Runner/VPN/VPNManager.swift

@@ -9,6 +9,20 @@ import Foundation
 import Combine
 import NetworkExtension
 
+enum VPNManagerAlertType: String {
+    case RequestVPNPermission
+    case RequestNotificationPermission
+    case EmptyConfiguration
+    case StartCommandServer
+    case CreateService
+    case StartService
+}
+
+struct VPNManagerAlert {
+    let alert: VPNManagerAlertType?
+    let message: String?
+}
+
 class VPNManager: ObservableObject {
     private var cancelBag: Set<AnyCancellable> = []
     
@@ -20,6 +34,7 @@ class VPNManager: ObservableObject {
     static let shared: VPNManager = VPNManager()
         
     @Published private(set) var state: NEVPNStatus = .invalid
+    @Published private(set) var alert: VPNManagerAlert = .init(alert: nil, message: nil)
     
     @Published private(set) var upload: Int64 = 0
     @Published private(set) var download: Int64 = 0