@@ -0,0 +1,261 @@
+//
+//  LoginViewController_TVING.swift
+//  GO_SOPT_Seminar_Assingment
+//
+//  Created by 김다예 on 2023/04/11.
+//
+
+import UIKit
+
+import SnapKit
+import Then
+
+struct TvingUserInfo {
+    var id: String?
+    var password: String?
+    var nickName: String?
+}
+
+final class LoginViewController_TVING: BaseViewController {
+    
+    // MARK: - Property
+    
+    private let mainView = LoginView()
+    private let nickNameBottomSheet = AddNickNameBottomSheetUIView()
+    
+    var user = TvingUserInfo()
+    
+    private var bottomSheetKeyboardEnable: Bool = false
+    
+    // MARK: - Target
+    
+    private func target() {
+        mainView.idTextField.delegate = self
+        mainView.passwordTextField.delegate = self
+        
+        mainView.idTextField.addTarget(self, action: #selector(textFieldDidChange), for: .allEditingEvents)
+        mainView.passwordTextField.addTarget(self, action: #selector(textFieldDidChange), for: .allEditingEvents)
+        
+        mainView.logInBtn.addTarget(self, action: #selector(tappedLogInBtn), for: .touchUpInside)
+        mainView.goToMakeNicknameBtn.addTarget(self, action: #selector(tappedMakeNickNameBtn), for: .touchUpInside)
+    }
+    
+    private func targetBottomSheet() {
+        nickNameBottomSheet.nickNameTextField.delegate = self
+        
+        nickNameBottomSheet.nickNameTextField.addTarget(self, action: #selector(textFieldDidChange), for: .allEditingEvents)
+        
+        nickNameBottomSheet.saveNickNameBtn.addTarget(self, action: #selector(tappedSavedNickNameBtn), for: .touchUpInside)
+        
+        let bottomSheetBackgroundTap = UITapGestureRecognizer(target: self, action: #selector(TappedBottomSheetBackground))
+        nickNameBottomSheet.dimmendView.addGestureRecognizer(bottomSheetBackgroundTap)
+    }
+    
+    // MARK: - Lift Cycle
+    
+    override func loadView() {
+        self.view = mainView
+        view.addSubview(nickNameBottomSheet)
+        
+        nickNameBottomSheet.snp.makeConstraints {
+            $0.width.equalToSuperview()
+            $0.top.equalTo(view.snp.bottom)
+        }
+    }
+    
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        
+        target()
+        targetBottomSheet()
+        setKeyboardObserver()   // 키보드 활성화에 따른 bottomSheet 높이 조절 위해
+    }
+    
+    override func viewWillAppear(_ animated: Bool) {
+        initView()
+    }
+
+}
+
+private extension LoginViewController_TVING {
+    
+    // MARK: - objc func
+    
+    @objc
+    func tappedLogInBtn() {
+        saveUserEmail()
+        let welcomViewController = WelcomeViewController()
+        welcomViewController.idDataBind(idOrNick: getNickNameOrId())
+        self.navigationController?.pushViewController(welcomViewController, animated: true)
+    }
+    
+    @objc
+    func tappedMakeNickNameBtn() {
+        showBottomSheet()
+    }
+    
+    @objc
+    func tappedSavedNickNameBtn() {
+        saveUserNickName()
+        hideBottomSheet()
+    }
+    
+    @objc func TappedBottomSheetBackground(_ tapRecognizer: UITapGestureRecognizer) {
+        hideBottomSheet()
+    }
+    
+    @objc func keyboardWillShow(notification: NSNotification) {
+        guard let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else { return }
+        if (nickNameBottomSheet.nickNameTextField.isSelected){
+            bottomSheetKeyboardEnable = true
+            nickNameBottomSheet.bottomSheetView.frame.origin.y = UIScreen.main.bounds.height - (nickNameBottomSheet.bottomSheetHeight + keyboardSize.height)
+        }
+    }
+    
+    @objc func keyboardWillHide(notification: NSNotification) {
+        if (nickNameBottomSheet.nickNameTextField.isSelected){
+            bottomSheetKeyboardEnable = true
+            nickNameBottomSheet.bottomSheetView.frame.origin.y = UIScreen.main.bounds.height - nickNameBottomSheet.bottomSheetHeight
+        }
+    }
+    
+    // MARK: - custom func
+    
+    func saveUserEmail(){
+        guard let id = mainView.idTextField.text else { return }
+        user.id = id
+    }
+    
+    func saveUserNickName() {
+        guard let nickName = nickNameBottomSheet.nickNameTextField.text else { return }
+        user.nickName = nickName
+    }
+    
+    func getNickNameOrId() -> String {
+        if let nickName = user.nickName {
+            return nickName
+        } else {
+            guard let id = user.id else { return "" }
+            return id
+        }
+    }
+    
+    func isIDValid() -> Bool {
+        guard let id = mainView.idTextField.text else { return false }
+        return id.isValidEmail()
+    }
+    
+    func showBottomSheet() {
+        nickNameBottomSheet.nickNameTextField.isSelected = true
+        nickNameBottomSheet.snp.remakeConstraints {
+            $0.edges.equalToSuperview()
+        }
+        UIView.animate(withDuration: 0.5, animations: {
+            self.nickNameBottomSheet.frame = CGRect(x: 0.0, y: 0.0, width: self.view.frame.width, height: self.view.frame.height)
+        })
+    }
+    
+    func hideBottomSheet() {
+        nickNameBottomSheet.nickNameTextField.isSelected = false
+        nickNameBottomSheet.snp.remakeConstraints {
+            $0.width.equalToSuperview()
+            $0.top.equalTo(view.snp.bottom)
+        }
+        UIView.animate(withDuration: 0.5, animations: {
+            self.nickNameBottomSheet.frame = CGRect(x: 0.0, y: self.view.frame.height, width: self.view.frame.width, height: self.view.frame.height)
+            }
+        )
+    }
+    
+    func initView() {
+        mainView.idTextField.text = nil
+        mainView.passwordTextField.text = nil
+        nickNameBottomSheet.nickNameTextField.text = nil
+        user = TvingUserInfo()
+        mainView.logInBtn.enableDisableButtonSet(isEnable: false, setColor: .black, setTextColor: .tvingGray2)
+    }
+    
+    func setKeyboardObserver() {
+        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
+        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
+    }
+    
+}
+
+// MARK: - TextFieldDelegate
+
+extension LoginViewController_TVING: UITextFieldDelegate {
+    
+    // textField가 활성화되면
+    func textFieldDidBeginEditing(_ textField: UITextField) {
+        textField.layer.borderColor = UIColor.tvingGray2.cgColor
+        textField.layer.borderWidth = 0.7
+    }
+
+    // textField 비활성화되면
+    func textFieldShouldEndEditing(_ textField: UITextField) -> Bool {
+        textField.layer.borderWidth = 0
+        
+        idValidPrint()
+            
+        return true
+    }
+    
+    @objc
+    private func textFieldDidChange(_ textField: UITextField) {
+        
+        if let nickNameText = nickNameBottomSheet.nickNameTextField.text {
+            if (!nickNameText.isValidNickName()) {
+                nickNameBottomSheet.nickNameTextField.text = nil
+            }
+        }
+        
+        let idPwIsFull: Bool = mainView.idTextField.hasText && !mainView.passwordTextField.hasText
+        let saveIdPwBtnEnable: Bool = idPwIsFull && isIDValid()
+        
+        if (saveIdPwBtnEnable) {
+            mainView.logInBtn.enableDisableButtonSet(isEnable: saveIdPwBtnEnable, setColor: .tvingRed, setTextColor: .white)
+        }else {
+            mainView.logInBtn.enableDisableButtonSet(isEnable: saveIdPwBtnEnable, setColor: .black, setTextColor: .tvingGray2)
+        }
+        
+        let saveNickNameBtnEnable = !nickNameBottomSheet.nickNameTextField.hasText
+    
+        if (saveNickNameBtnEnable) {
+            nickNameBottomSheet.saveNickNameBtn.enableDisableButtonSet(isEnable: saveNickNameBtnEnable, setColor: .tvingRed, setTextColor: .white)
+        }else {
+            nickNameBottomSheet.saveNickNameBtn.enableDisableButtonSet(isEnable: saveNickNameBtnEnable, setColor: .black, setTextColor: .tvingGray2)
+        }
+    }
+    
+    private func idValidPrint() {
+        
+        if (!(mainView.idTextField.text?.isValidEmail() ?? false) && !mainView.idTextField.hasText) {
+            mainView.idTextField.layer.borderColor = UIColor.tvingRed.cgColor
+            mainView.idTextField.layer.borderWidth = 0.7
+            
+            mainView.idInvalidLabel.isHidden = false
+            mainView.idInvalidLabel.snp.remakeConstraints {
+                $0.leading.equalTo(mainView.idTextField.snp.leading)
+                $0.top.equalTo(mainView.idTextField.snp.bottom).offset(5)
+            }
+            
+            mainView.passwordTextField.snp.remakeConstraints {
+                $0.height.equalTo(52)
+                $0.top.equalTo(mainView.idTextField.snp.bottom).offset(30)
+                $0.leading.trailing.equalToSuperview().inset(20)
+            }
+        } else {
+            mainView.idTextField.layer.borderWidth = 0
+            
+            mainView.idInvalidLabel.isHidden = true
+            
+            mainView.passwordTextField.snp.remakeConstraints {
+                $0.height.equalTo(52)
+                $0.top.equalTo(mainView.idTextField.snp.bottom).offset(7)
+                $0.leading.trailing.equalToSuperview().inset(20)
+            }
+        }
+    }
+    
+}

리뷰: 스위프트에서 접근 제어자를 따로 선언하지 않으면 internal 접근이 기본이라고 해요!
open-> public -> internal -> file-private -> private 으로 갈 수록 제한적인 접근자인데
서로 다른 모듈끼리 접근하는 상황이 아니라면 
굳이 public을 선언하여 접근 수준을 약하게 할 필요 없다고 생각하는데 어떻게 생각하세용?

https://zeddios.tistory.com/383