import Foundation
import Alamofire


class User {


    let defaults = UserDefaults.standard

    var email: String
    var password: String
    var isLoggedIn: Bool

    init(email: String, password: String) {
        self.email = email
        self.password = password
        self.isLoggedIn = false
    }

    // Perform authentication
    func authenticateUser(user: User, completionHandler: @escaping (_ result: Bool) -> ()) {
        makeAuthenticateUserCall(user: user, completionHandler: completionHandler)
    }

    // Perform POST request
    func makeAuthenticateUserCall(user: User, completionHandler: @escaping (Bool) -> ()) {

        let parameters = [
            "email" : user.email,
            "password" : user.password
        ]

        Alamofire.request("http://apistaging.server.com/api/v1/login", method: .post, parameters: parameters, encoding:  URLEncoding.httpBody).responseJSON {response in

                switch response.result {
                case .success:
                    if let json = response.result.value as? [String: Any],
                        let status = json["status"] as? String,
                        status == "success" {
                        completionHandler(true)
                    }
                case .failure:
                    completionHandler(false)
                }
        }
    }
}

// Код из ViewController:

    @IBAction func loginButtonPressed(_ sender: UIButton) {

        if let email = _email.text {
            if let password = _password.text {
                let user = User(email: email, password: password)
                user.authenticateUser(user: user) {resultBool in
                        user.isLoggedIn = resultBool
                    }
                if user.isLoggedIn {
                    self.performSegue(withIdentifier: "MainPageViewController", sender: nil)
                }
            }
        }
    }