LoginController에서 컴바인을 통해 ViewModel로 분리. 가독성, 클린코드를 고려한 리펙터링.

Clone App/Instagram/Instagram/Controller/Authentication/LoginController.swift

@@ -7,40 +7,30 @@
 
 import UIKit
 import Firebase
-
-/**
-    이번에 할거는 LoginController를 MVVM으로 리펙터링 할 것이다. 물론 로그인 컨트롤과 연관된 서비스도 리펙터링
- 
- */
-
-protocol AuthentificationDelegate: class {
-    func authenticationCompletion(uid: String) async
-}
+import Combine
 
 class LoginController: UIViewController {
 
     //MARK: - Properties
-    weak var authDelegate: AuthentificationDelegate?
     private let instagramIcon: UIImageView = initialInstagramIcon()
-    private lazy var emailTextField: CustomTextField = initialEmailTextField()
-    private lazy var passwdTextField: CustomTextField = initialPasswdTextField()
+    private lazy var emailTextField: UITextField = initialEmailTextField()
+    private lazy var passwdTextField: UITextField = initialPasswdTextField()
     private lazy var loginButton: LoginButton = initialLoginButton()
     private lazy var forgotHelpLineStackView: UIStackView = initialForgotStackView()
     private lazy var signUpLineStackView: UIStackView = initialSignUpLineStackView()
-    private var indicator: UIActivityIndicatorView = UIActivityIndicatorView(style: .medium)
 
-    private var vm = LoginViewModel()
+    var viewModel: LoginViewModel = LoginViewModel()
+    private var subscriptions: Set<AnyCancellable> = Set<AnyCancellable>()
+    private var tapLogin: PassthroughSubject<UIViewController,Never> = PassthroughSubject<UIViewController,Never>()
 
     //MARK: - Life cycle
-
     override func viewDidLoad() {
         super.viewDidLoad()
         setupUI()
-        setupTextFieldBindingByViewModel()
+        setupBindings()
     }
 }
 
-
 //MARK: - View helpers
 extension LoginController {
 
@@ -67,23 +57,8 @@ extension LoginController {
 
     @objc func didTapLoginButton(_ sender: Any) {
         startIndicator(indicator: indicator)
-        let email = vm.email.value
-        let pw = vm.password.value
-        guard let vc = self.presentingViewController as? MainHomeTabController else {
-            return
-        }
-        Task() {
-            do {
-                guard let authDataResult = try await AuthService.handleIsLoginAccount(email: email, pw: pw) else { throw FetchUserError.invalidUserInfo }
-                endIndicator(indicator: indicator)
-                vc.view.isHidden = false
-                await authDelegate?.authenticationCompletion(uid: authDataResult.user.uid)
-            }catch FetchUserError.invalidUserInfo {
-                print("DEBUG: Fail to bind userInfo")
-            }catch {
-                print("DEBUG: Failure an occured error: \(error.localizedDescription) ")
-            }
-        }
+        guard let presentingViewController = presentingViewController else { return }
+        tapLogin.send(presentingViewController)
     }
 
     @objc func didTapHelpButton(_ sender: Any) {
@@ -97,40 +72,46 @@ extension LoginController {
 
 }
 
-
 //MARK: - Helpers
 extension LoginController {
 
-    //vm의 값이 바뀌면 현재 연결된 UITextField의 쳐져있는 값도 변경.
-    func setupTextFieldBindingByViewModel() {
-        vm.email.bind{ [weak self] text in
-            self?.emailTextField.text = text
-        }
-        vm.password.bind{ [weak self] text in
-            self?.passwdTextField.text = text
-        }
-    }
-
-    func changeValidTextFields() {
-        if vm.isValiedUserForm {
-            DispatchQueue.main.async {
-                self.loginButton.isEnabled = true
-                self.loginButton.backgroundColor = UIColor.systemPink.withAlphaComponent(0.6)
-                self.loginButton.titleLabel?.textColor.withAlphaComponent(1)
-            }
-        } else {
-            DispatchQueue.main.async {
-                self.loginButton.isEnabled = false
-                self.loginButton.backgroundColor = UIColor.systemPink.withAlphaComponent(0.3)
-                self.loginButton.titleLabel?.textColor.withAlphaComponent(0.2)
-            }
-        }
+    func setupBindings() {
+
+        subscriptions.forEach { $0.cancel() }
+        subscriptions.removeAll()
+
+        let input = LoginViewModelInput(tapLogin: tapLogin.eraseToAnyPublisher())
+        viewModel.login(with: input)
+
+        textfieldNotificationPublisher(withTF: emailTextField)
+            .receive(on: RunLoop.main)
+            .sink { [unowned self] text in
+                viewModel.email = text
+                viewModel.checkIsValidTextFields(withLogin: loginButton)
+            }.store(in: &subscriptions)
+
+        textfieldNotificationPublisher(withTF: passwdTextField)
+            .receive(on: RunLoop.main)
+            .sink { [unowned self] text in
+                viewModel.passwd = text
+                viewModel.checkIsValidTextFields(withLogin: loginButton)
+            }.store(in: &subscriptions)
+
+    }
+
+    func textfieldNotificationPublisher(withTF textField: UITextField) -> AnyPublisher<String,NotificationCenter.Publisher.Failure> {
+        return NotificationCenter.default
+            .publisher(for: UITextField.textDidChangeNotification,object: textField)
+            .map {
+                guard let text = ($0.object as? UITextField)?.text else {
+                    return ""
+                }
+                return text
+            }.eraseToAnyPublisher()
     }
 
 }
 
-
-
 //MARK: - Setup Navigation
 extension LoginController {
     func setupNavigationAppearance() {
@@ -157,30 +138,20 @@ extension LoginController {
         let iv = UIImageView()
         iv.translatesAutoresizingMaskIntoConstraints = false
         iv.image = .imageLiteral(name: "Instagram_logo_white")
-
         return iv
     }
 
     func initialEmailTextField() -> CustomTextField {
         let tf = CustomTextField(placeHolder: "Email")
         tf.keyboardType = .emailAddress
         tf.setHeight(50)
-        tf.bind{ [weak self] text in
-            self?.vm.email.value = text
-            self?.changeValidTextFields()
-        }
         return tf
     }
 
     func initialPasswdTextField() -> CustomTextField {
         let tf = CustomTextField(placeHolder: "Password")
         tf.isSecureTextEntry = true
         tf.setHeight(50)
-        tf.bind { [weak self] text in
-            self?.vm.password.value = text
-            self?.changeValidTextFields()
-        }
-
         return tf
     }
 

Clone App/Instagram/Instagram/Model/LoginViewModelInput.swift

@@ -5,4 +5,11 @@
 //  Created by 양승현 on 2022/12/08.
 //
 
-import Foundation
+import UIKit
+import Combine
+
+
+///define UI events
+struct LoginViewModelInput {
+    var tapLogin: AnyPublisher<UIViewController,Never>
+}

Clone App/Instagram/Instagram/Protocols/LoginViewModelProtocols.swift

@@ -5,4 +5,37 @@
 //  Created by 양승현 on 2022/12/08.
 //
 
-import Foundation
+import UIKit
+import Combine
+
+protocol AuthentificationDelegate: class {
+
+    /// 회원이라면 메인화면으로 돌아간다.
+    /// 이때 Firebase  에서 지원하는 Auth.auth().currentUser는 잘 동작하지 않는다.
+    /// 초기에는 동작하지만 중간에 사용자가 로그아웃 후 다른 계정으로 로그인 할 경우 currentuser의 캐시가 변경되지 않는다고 한다.
+    /// 그래서 영구 저장소에 저장하고 갱신하기 위해 로그인된 유저의 uid를 따로 반환한다.
+    func authenticationCompletion(uid: String) async
+
+}
+
+
+protocol LoginViewModelType {
+
+    /// 사용자가 로그인, 비밀번호 칸을 두개 다 입력 했는지 체크 여부 반환한다.
+    /// 추후 비밀번호 최소 입력 개수를 제한하고 알림창을 띄우는 기능을 추가할 것이다.
+    func isValidUserForm() -> AnyPublisher<Bool,Never>
+
+    /// 입력한 email, pw 두 userForm을 통해 회원인지 아닌지 확인한다.
+    func checkIsValidTextFields(withLogin button: UIButton)
+
+    /// LoginController에서 ViewModel로 login 입력이 들어온다.
+    func login(with input: LoginViewModelInput)
+
+}
+
+protocol LoginViewModelAPIType {
+
+    /// Async, Await을 통해 회원 여부 판단을 request하는 server api관련 wrapper func.
+    func loginInputAccount(mainHomeTab vc: MainHomeTabController)
+
+}

Clone App/Instagram/Instagram/ViewModel/Authentification/LoginViewModel.swift

@@ -5,4 +5,77 @@
 //  Created by 양승현 on 2022/12/07.
 //
 
-import Foundation
+import UIKit
+import Combine
+
+final class LoginViewModel {
+
+    //MARK: - Properties
+    weak var authDelegate: AuthentificationDelegate?
+    @Published var email: String = ""
+    @Published var passwd: String = ""
+    var subscriptions: Set<AnyCancellable> = Set<AnyCancellable>()
+
+}
+
+//MARK: - LoginViewModelType
+extension LoginViewModel: LoginViewModelType {
+
+    func isValidUserForm() -> AnyPublisher<Bool, Never> {
+        $email
+            .zip($passwd)
+            .map { (emailText, passwdText) in
+                return !emailText.isEmpty && !passwdText.isEmpty
+            }.eraseToAnyPublisher()
+    }
+
+    func checkIsValidTextFields(withLogin button: UIButton) {
+        isValidUserForm()
+            .receive(on: RunLoop.main)
+            .sink{ isValied in
+                if isValied {
+                    button.isEnabled = true
+                    button.backgroundColor = UIColor.systemPink.withAlphaComponent(0.6)
+                    button.titleLabel?.textColor.withAlphaComponent(1)
+                } else {
+                    button.isEnabled = false
+                    button.backgroundColor = UIColor.systemPink.withAlphaComponent(0.3)
+                    button.titleLabel?.textColor.withAlphaComponent(0.2)
+                }
+            }.store(in: &subscriptions)
+    }
+
+    func login(with input: LoginViewModelInput) {
+        subscriptions.forEach{ $0.cancel() }
+        subscriptions.removeAll()
+
+        input
+            .tapLogin
+            .receive(on: RunLoop.main)
+            .sink { [unowned self] presentingVC in
+                guard let vc = presentingVC as? MainHomeTabController else { return }
+                vc.view.isHidden = false
+                loginInputAccount(mainHomeTab: vc)
+            }.store(in: &subscriptions)
+    }
+
+}
+
+//MARK: - LoginViewModelAPIType
+extension LoginViewModel: LoginViewModelAPIType {
+
+    func loginInputAccount(mainHomeTab vc: MainHomeTabController) {
+        Task() {
+            do {
+                guard let authDataResult = try await AuthService.handleIsLoginAccount(email: email, pw: passwd) else { throw FetchUserError.invalidUserInfo }
+                await authDelegate?.authenticationCompletion(uid: authDataResult.user.uid)
+                await vc.endIndicator(indicator: indicator)
+            }catch FetchUserError.invalidUserInfo {
+                print("DEBUG: Fail to bind userInfo")
+            }catch {
+                print("DEBUG: Failure an occured error: \(error.localizedDescription) ")
+            }
+        }
+    }
+
+}