LWAViewController.swift

//
//  ViewController.swift
//  AuthLWA
//
//  Created by Hills, Dennis on 12/7/18.
//  Copyright © 2018 Hills, Dennis. All rights reserved.
//  
//  Requires LoginWithAmazonProxy via Gist here: https://gist.github.com/mobilequickie/56916503a41ebb2374fea241ede26eab
//  This gist: https://gist.github.com/mobilequickie/47a238e073043a271425f7ffe9d56d5e
//

import UIKit
import LoginWithAmazon
import AWSMobileClient

class ViewController: UIViewController, AIAuthenticationDelegate {
    
    @IBOutlet weak var lblIdentityId: UILabel!
    @IBOutlet weak var btnLWALogin: UIButton!
    @IBOutlet weak var btnLWALogout: UIButton!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        initializeAWSMobileClient() // Initialize the AWSMobileClient
        
        lblIdentityId.text = AWSMobileClient.sharedInstance().identityId
    }
    
    // Initializing the AWSMobileClient and take action based on current user state
    func initializeAWSMobileClient() {
        AWSMobileClient.sharedInstance().initialize { (userState, error) in
                                      
            self.addUserStateListener() // Register for user state changes
            
            if let userState = userState
                switch(userState){
                case .signedIn: // is Signed IN
                    print("Logged In")
                    print("Cognito Identity Id (authenticated): \(AWSMobileClient.sharedInstance().identityId))")
                     DispatchQueue.main.async {
                        self.btnLWALogin.isEnabled = false
                        self.btnLWALogout.isEnabled = true
                    }
                case .signedOut: // is Signed OUT
                    print("Logged Out")
                    DispatchQueue.main.async {
                        self.btnLWALogin.isEnabled = true
                        self.btnLWALogout.isEnabled = false
                    }
                case .signedOutUserPoolsTokenInvalid: // User Pools refresh token INVALID
                    print("User Pools refresh token is invalid or expired.")
                    DispatchQueue.main.async {
                        //self.showSignIn()  // If implemented drop-in auth UI for User Pools call that UI here.
                    }
                case .signedOutFederatedTokensInvalid: // Login with Amazon, Facebook, or Google refresh token is INVALID
                    print("Federated refresh token is invalid or expired.")
                    DispatchQueue.main.async {
                        self.btnLWALogin.isEnabled = true
                        self.btnLWALogout.isEnabled = false
                    }
                default:
                    AWSMobileClient.sharedInstance().signOut()
                }
            } else if let error = error {
                print(error.localizedDescription)
            }
        }
    }

    func addUserStateListener() {
        AWSMobileClient.sharedInstance().addUserStateListener(self) { (userState, info) in
            switch (userState) {
                
            case .guest:
                print("user is not signed in (unauthenticated)")
                DispatchQueue.main.async(execute: { () -> Void in
                    self.lblIdentityId.text = AWSMobileClient.sharedInstance().identityId
                })
                
            case .signedIn:
                DispatchQueue.main.async(execute: { () -> Void in
                    self.btnLWALogin.isEnabled = false
                    self.btnLWALogout.isEnabled = true
                })
                print("user is signed in (authenticated)")
                
                DispatchQueue.main.async(execute: { () -> Void in
                    self.lblIdentityId.text = AWSMobileClient.sharedInstance().identityId
                })
                
            case .signedOut:
                print("user signed out")
                DispatchQueue.main.async(execute: { () -> Void in
                    self.btnLWALogin.isEnabled = true
                    self.btnLWALogout.isEnabled = false
                })
                DispatchQueue.main.async(execute: { () -> Void in
                    self.lblIdentityId.text = AWSMobileClient.sharedInstance().identityId
                })
                
            case .signedOutUserPoolsTokenInvalid:
                print("need to login again.") // Show drop-in auth UI for Cognito User Pools if you have basic auth enabled
            
            case .signedOutFederatedTokensInvalid: // Login with Amazon refresh token has expired. Re-authenticate
                LoginWithAmazonProxy.sharedInstance.login(delegate: self) 
            
            default:
                print("unsupported")
            }
        }
    }
    
    // User taps [Login with Amazon] button
    @IBAction func onClickLWALogin(_ sender: Any) {
        LoginWithAmazonProxy.sharedInstance.login(delegate: self)
    }
    
    // User taps [Logout]
    @IBAction func onClickLWALogout(_ sender: Any) {
        LoginWithAmazonProxy.sharedInstance.logout(delegate: self)
    }
    
    func AMZNSignOutRequestHandler(_ apiResult: APIResult!) {
        print("Sign out callback")
    }
    
    // Login with Amazon - Successful login callback
    func requestDidSucceed(_ apiResult: APIResult!) {
        
        switch (apiResult.api) {
        
        case API.authorizeUser:
            LoginWithAmazonProxy.sharedInstance.getAccessToken(delegate: self)
        
        case API.getAccessToken:
            print("LWA Access Token: \(apiResult.result)")
            guard let LWAtoken = apiResult.result as? String else { return }
            
            // Get the user profile from LWA
            LoginWithAmazonProxy.sharedInstance.getUserProfile(delegate: self)
            
            // To federate Login with Amazon (LWA) as a sign-in provider, pass tokens to AWSMobileClient.sharedInstance().federatedSignIn()
            AWSMobileClient.sharedInstance().federatedSignIn(providerName: IdentityProvider.amazon.rawValue, token: LWAtoken ) { (userState,err) in
                if let error = err {
                    print("Federated SignIn failed for LWA: \(error.localizedDescription)")
                }
            }
        
        case API.getProfile:
            print("LWA User Profile: \(apiResult.result)")
        
        case API.clearAuthorizationState:
            print("user logged out from LWA")
            
            // Sign out from AWSMobileClient
            AWSMobileClient.sharedInstance().signOut()
            
        default:
            print("unsupported")
        }
    }
    
    // Login with Amazon - callback error
    func requestDidFail(_ errorResponse: APIError!) {
        print("Error: \(errorResponse.error.message ?? "nil")")
    }
}