```Swift

import UIKit

import Foundation

import Firebase

import FirebaseAuth

import GoogleSignIn

import FBSDKLoginKit

import SCLAlertView

import UserNotifications





class LoginViewController: UIViewController{

   

  @IBOutlet weak var emailTextField: UITextField!

   

  @IBOutlet weak var passwordTextField: UITextField!

   

  @IBOutlet weak var loginButton: UIButton!

   

  @IBOutlet weak var errorLabel: UILabel!

   

  @IBOutlet weak var passwordEye: UIImageView!

   

  @IBOutlet weak var googlrLoginButton: UIButton!

  var error: Error?

   

  @IBOutlet weak var forgotPassword: UILabel!



  @IBOutlet weak var fbLoginButton: UIButton!

   

   

  override func viewDidLoad() {

    super.viewDidLoad()

    passwordTextField!.isSecureTextEntry = true

    passwordEye!.isUserInteractionEnabled = true

    passwordEye!.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(eyeSelected)))

     

    forgotPassword!.isUserInteractionEnabled = true

    forgotPassword!.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(forgotPasswordSelected)))

     

     

    let spacerView = UIView(frame:CGRect(x:0, y:0, width:30, height:10))

    passwordTextField.leftViewMode = UITextField.ViewMode.always

    passwordTextField.leftView = spacerView

     

    let spacerView2 = UIView(frame:CGRect(x:0, y:0, width:30, height:10))

    emailTextField.leftViewMode = UITextField.ViewMode.always

    emailTextField.leftView = spacerView2

     

    loginButton.layer.cornerRadius = 10

    loginButton.clipsToBounds = true

    googlrLoginButton.layer.cornerRadius = googlrLoginButton.frame.width / 2

    googlrLoginButton.layer.masksToBounds = true

    fbLoginButton.layer.cornerRadius =

      fbLoginButton.frame.width / 2

    fbLoginButton.layer.masksToBounds = true

    errorLabel.alpha=0

  }

  

  func aftergoogledismiss(){

    GIDSignIn.sharedInstance().delegate = self

  }

   

  override func viewWillDisappear(_ animated: Bool) {

    aftergoogledismiss()

  }

  override func viewWillAppear(_ animated: Bool) {

    aftergoogledismiss()

  }

   

  var googleSignIn = GIDSignIn.sharedInstance()

   

  @IBAction func googleLoginButtonPressed(_ sender: Any){

   

    self.googleAuthLogin()

     

  }

   

  func googleAuthLogin() {

    self.googleSignIn?.presentingViewController = self

    self.googleSignIn?.clientID = "122963184918-q1kp62b948nav07cl6265d0s6r6e173e.apps.googleusercontent.com"

    self.googleSignIn?.delegate = self

    self.googleSignIn?.signIn()

  }

   

  @IBAction func didChangeSegement(_ sender:UISegmentedControl){

    if sender.selectedSegmentIndex == 1{

      let vc = storyboard?.instantiateViewController(identifier: "signupVC") as! SignupViewController

      vc.modalPresentationStyle = .fullScreen

      present(vc, animated: true)

    }

  }

   

   

  @IBAction func loginButtonTapped(_ sender: UIButton) {

     

    let email = emailTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)

    let password = passwordTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)

     

    Auth.auth().signIn(withEmail: email, password: password) { (result, error) in

       

       

      if error != nil {

         

        sender.shake()

        SCLAlertView().showError("Oof",subTitle:"😱It looks like there was an error😱")

      } else {

         

        sender.pulsate()

        let homeViewController = self.storyboard?.instantiateViewController(identifier: "homeVC") as! HomeViewController

         

        homeViewController.modalPresentationStyle = .fullScreen

        self.present(homeViewController, animated: true)

         

      }

    }

  }

   

   

   

  @objc private func eyeSelected(){

    passwordTextField.isSecureTextEntry.toggle()

    if passwordTextField.isSecureTextEntry == true{

      passwordEye.image = UIImage(systemName: "eye")

    }else{

      passwordEye.image = UIImage(systemName: "eye.fill")

    }

  }

   

   

  @objc private func forgotPasswordSelected(){

    let email = emailTextField.text!.trimmingCharacters(in: .whitespacesAndNewlines)

    Auth.auth().sendPasswordReset(withEmail: email) { (error) in

       

      if error != nil{

        SCLAlertView().showError("Oof",subTitle:"😱It looks like there was an error.😱")

      }else{

        self.emailTextField.text = ""

      }

    }

  }

   

  

  @IBAction func fbLoginButtonPressed(_ sender: Any) {

    let fbLoginManager = LoginManager()

    fbLoginManager.logIn(permissions: ["public_profile", "email"], from: self) { (result, error) in

      if error != nil {

        SCLAlertView().showError("Oof",subTitle:"😱It looks like there was an error😱")

        return

      }

       

      guard let accessToken = AccessToken.current else {

        SCLAlertView().showError("Oof",subTitle:"😱It looks like there was an error😱")

        return

      }

       

      let credential = FacebookAuthProvider.credential(withAccessToken: accessToken.tokenString)

       

      Auth.auth().signIn(with: credential, completion: { (user, error) in

        if error != nil {

          SCLAlertView().showError("Oof",subTitle:"😱It looks like there was an error😱")

          return

        }

        else {

           

          let connection = GraphRequestConnection()

              connection.add(GraphRequest(graphPath: "/me", parameters: ["fields" : "id,name,about,birthday"], httpMethod: .get)) { (connection, response, error) in

              if error != nil {

                SCLAlertView().showError("Oof",subTitle:"😱It looks like there was an error😱")

                } else {

                guard (response as? Dictionary<String,Any>) != nil else {

                    return

                  }

                  

                }

              }

              connection.start()

           

          let homeViewController = self.storyboard?.instantiateViewController(identifier: "homeVC") as! HomeViewController

           

          homeViewController.modalPresentationStyle = .fullScreen

          self.present(homeViewController, animated: true)

           

        }

      })

       

    }

  }

   

   

   

   

}



extension UIButton {

   

  func pulsate() {

     

    let pulse = CASpringAnimation(keyPath: "transform.scale")

    pulse.duration = 0.2

    pulse.fromValue = 0.95

    pulse.toValue = 1.0

    pulse.autoreverses = true

    pulse.repeatCount = 2

    pulse.initialVelocity = 0.5

    pulse.damping = 1.0

     

    layer.add(pulse, forKey: nil)

  }

   

  func shake(){

     

    let shake = CABasicAnimation(keyPath: "position")

    shake.duration = 0.1

    shake.repeatCount = 2

    shake.autoreverses = true

     

    let fromPoint = CGPoint(x: center.x-5, y: center.y)

    let fromValue = NSValue(cgPoint: fromPoint)

     

    let toPoint = CGPoint(x: center.x + 5, y: center.y)

    let toValue = NSValue(cgPoint: toPoint)

     

    shake.fromValue = fromValue

    shake.toValue = toValue

     

    layer.add(shake, forKey: nil)

  }

}



extension LoginViewController: GIDSignInDelegate {

  func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error!) {

      guard let user = user else {

        SCLAlertView().showError("Oof",subTitle:"😱It looks like there was an error😱")

        return

      }

      let userId = user.userID ?? ""

     

       

      let userIdToken = user.authentication.idToken ?? ""

       

      let userEmail = user.profile.email ?? ""

     

    let userInfo = ["username":userId,"email":userEmail, "password":"not given"]

     

     

     

       

    let homeViewController = self.storyboard?.instantiateViewController(identifier: "homeVC") as! HomeViewController

     

    homeViewController.modalPresentationStyle = .fullScreen

    self.present(homeViewController, animated: true)

       

    }

   

  func sign(_ signIn: GIDSignIn!, didDisconnectWith user: GIDGoogleUser!, withError error: Error!) {

     

  }

}



```