Thêm tính năng đăng nhập vào ứng dụng iOS bằng FirebaseUI

import FirebaseAppleSwiftUI
import FirebaseAuthSwiftUI
import FirebaseGoogleSwiftUI
import SwiftUI

struct ContentView: View {
  let authService: AuthService

  init() {
    // Create configuration with options
    let configuration = AuthConfiguration(
      tosUrl: URL(string: "https://example.com/tos"),
      privacyPolicyUrl: URL(string: "https://example.com/privacy"),
      shouldAutoUpgradeAnonymousUsers: true
    )

    // Initialize AuthService with multiple providers
    authService = AuthService(configuration: configuration)
      .withEmailSignIn()
      .withAppleSignIn()
      .withGoogleSignIn()
  }

  var body: some View {
    AuthPickerView {
      authenticatedContent
    }
    .environment(authService)
  }

  var authenticatedContent: some View {
    NavigationStack {
      VStack(spacing: 20) {
        if authService.authenticationState == .authenticated {
          Text("Authenticated")
          
          Button("Manage Account") {
            authService.isPresented = true
          }
          .buttonStyle(.bordered)
          
          Button("Sign Out") {
            Task {
              try? await authService.signOut()
            }
          }
          .buttonStyle(.borderedProminent)
        } else {
          Text("Not Authenticated")
          
          Button("Sign In") {
            authService.isPresented = true
          }
          .buttonStyle(.borderedProminent)
        }
      }
      .navigationTitle("My App")
    }
    .onChange(of: authService.authenticationState) { _, newValue in
      // Automatically show auth UI when not authenticated
      if newValue != .authenticating {
        authService.isPresented = (newValue == .unauthenticated)
      }
    }
  }
}

let configuration = AuthConfiguration(
    logo: ImageResource.exampleLogoAsset,
    customStringsBundle: .main,
    tosUrl: URL(string: "https://example.com/tos"),
    privacyPolicyUrl: URL(string: "https://example.com/privacy"),
)

import FirebaseAuthSwiftUI
import FirebaseTwitterSwiftUI
import SwiftUI

// Step 1: Create your custom button view
struct CustomTwitterButton: View {
  let provider: TwitterProviderSwift
  @Environment(AuthService.self) private var authService
  @Environment(\.mfaHandler) private var mfaHandler

  var body: some View {
    Button {
      Task {
        do {
          let outcome = try await authService.signIn(provider)

          // Handle MFA if required
          if case let .mfaRequired(mfaInfo) = outcome,
             let onMFA = mfaHandler {
            onMFA(mfaInfo)
          }
        } catch {
          // Do Something Else
        }
      }
    } label: {
      HStack { // Your custom icon
        Text("Sign in with Twitter")
          .fontWeight(.semibold)
      }
      .frame(maxWidth: .infinity)
      .padding()
      .background(
        LinearGradient(
          colors: [Color.blue, Color.cyan],
          startPoint: .leading,
          endPoint: .trailing
        )
      )
      .foregroundColor(.white)
      .cornerRadius(12)
      .shadow(radius: 4)
    }
  }
}

// Step 2: Create a custom AuthProviderUI wrapper
class CustomTwitterProviderAuthUI: AuthProviderUI {
  private let typedProvider: TwitterProviderSwift
  var provider: AuthProviderSwift { typedProvider }
  let id: String = "twitter.com"

  init(provider: TwitterProviderSwift = TwitterProviderSwift()) {
    typedProvider = provider
  }

  @MainActor func authButton() -> AnyView {
    AnyView(CustomTwitterButton(provider: typedProvider))
  }
}

// Step 3: Use it in your app
struct ContentView: View {
  let authService: AuthService

  init() {
    let configuration = AuthConfiguration()
    authService = AuthService(configuration: configuration)

    // Register your custom provider UI
    authService.registerProvider(
      providerWithButton: CustomTwitterProviderAuthUI()
    )
    authService.isPresented = true
  }

  var body: some View {
    AuthPickerView {
      usersApp
    }
    .environment(authService)
  }

  var usersApp: some View {
    NavigationStack {
      VStack {
        Button {
          authService.isPresented = true
        } label: {
          Text("Authenticate")
        }
      }
    }
  }
}

import FirebaseAuthSwiftUI
import FirebaseGoogleSwiftUI
import FirebaseAppleSwiftUI
import SwiftUI

// Custom Google Provider UI
class CustomGoogleProviderAuthUI: AuthProviderUI {
  private let typedProvider: GoogleProviderSwift
  var provider: AuthProviderSwift { typedProvider }
  let id: String = "google.com"
  
  init() {
    typedProvider = GoogleProviderSwift()
  }
  
  @MainActor func authButton() -> AnyView {
    AnyView(CustomGoogleButton(provider: typedProvider))
  }
}

struct CustomGoogleButton: View {
  let provider: GoogleProviderSwift
  @Environment(AuthService.self) private var authService
  
  var body: some View {
    Button {
      Task {
        try? await authService.signIn(provider)
      }
    } label: {
      HStack {
        Image(systemName: "g.circle.fill")
        Text("My Custom Google Button")
      }
      .frame(maxWidth: .infinity)
      .padding()
      .background(Color.purple) // Your custom color
      .foregroundColor(.white)
      .cornerRadius(10)
    }
  }
}

// Then use it
struct ContentView: View {
  let authService: AuthService
  
  init() {
    let configuration = AuthConfiguration()
    authService = AuthService(configuration: configuration)
      .withAppleSignIn() // Use default Apple button
    
    // Use custom Google button
    authService.registerProvider(
      providerWithButton: CustomGoogleProviderAuthUI()
    )
  }
  
  var body: some View {
    AuthPickerView {
      Text("App Content")
    }
    .environment(authService)
  }
}

import FirebaseAuthSwiftUI
import FirebaseGoogleSwiftUI
import FirebaseAppleSwiftUI
import SwiftUI

struct CustomAuthView: View {
  @Environment(AuthService.self) private var authService

  var body: some View {
    VStack(spacing: 30) {
      // Your custom logo/branding
      Image("app-logo")
        .resizable()
        .frame(width: 150, height: 150)
      
      Text("Welcome to My App")
        .font(.largeTitle)
        .fontWeight(.bold)
      
      Text("Sign in to continue")
        .font(.subheadline)
        .foregroundStyle(.secondary)
      
      // Render default auth buttons
      authService.renderButtons(spacing: 12)
        .padding()
    }
    .padding()
  }
}

struct ContentView: View {
  init() {
    let configuration = AuthConfiguration()
    
    authService = AuthService(configuration: configuration)
      .withGoogleSignIn()
      .withAppleSignIn()
  }
  
  let authService: AuthService

  var body: some View {
    NavigationStack {
      if authService.authenticationState == .authenticated {
        Text("Authenticated!")
      } else {
        CustomAuthView()
      }
    }
    .environment(authService)
  }
}

import FirebaseAuth
import FirebaseAuthSwiftUI
import FirebaseGoogleSwiftUI
import SwiftUI

enum CustomAuthRoute {
  case signIn
  case phoneVerification
  case mfaResolution
}

struct ContentView: View {
  private let authService: AuthService
  @State private var navigationPath: [CustomAuthRoute] = []
  @State private var errorMessage: String?

  init() {
    let configuration = AuthConfiguration()
    self.authService = AuthService(configuration: configuration)
      .withGoogleSignIn()
      .withPhoneSignIn()
  }

  var body: some View {
    NavigationStack(path: $navigationPath) {
      Group {
        if authService.authenticationState == .authenticated {
          authenticatedView
        } else {
          customSignInView
        }
      }
      .navigationDestination(for: CustomAuthRoute.self) { route in
        switch route {
        case .signIn:
          customSignInView
        case .phoneVerification:
          customPhoneVerificationView
        case .mfaResolution:
          customMFAView
        }
      }
    }
    .environment(authService)
    .alert("Error", isPresented: .constant(errorMessage != nil)) {
      Button("OK") {
        errorMessage = nil
      }
    } message: {
      Text(errorMessage ?? "")
    }
  }

  var customSignInView: some View {
    VStack(spacing: 20) {
      Text("Custom Sign In")
        .font(.title)
      
      Button("Sign in with Google") {
        Task {
          do {
            let provider = GoogleProviderSwift(clientID: Auth.auth().app?.options.clientID ?? "")
            let outcome = try await authService.signIn(provider)
            
            // Handle MFA if required
            if case .mfaRequired = outcome {
              navigationPath.append(.mfaResolution)
            }
          } catch {
            errorMessage = error.localizedDescription
          }
        }
      }
      .buttonStyle(.borderedProminent)
      
      Button("Phone Sign In") {
        navigationPath.append(.phoneVerification)
      }
      .buttonStyle(.bordered)
    }
    .padding()
  }

  var customPhoneVerificationView: some View {
    Text("Custom Phone Verification View")
    // Implement your custom phone auth UI here
  }

  var customMFAView: some View {
    Text("Custom MFA Resolution View")
    // Implement your custom MFA UI here
  }

  var authenticatedView: some View {
    VStack(spacing: 20) {
      Text("Welcome!")
      Text("Email: \(authService.currentUser?.email ?? "N/A")")
      
      Button("Sign Out") {
        Task {
          try? await authService.signOut()
        }
      }
      .buttonStyle(.borderedProminent)
    }
  }
}

do {
  try await authService.deleteUser()
} catch let error as AuthServiceError {
  if case .oauthReauthenticationRequired(let context) = error {
    try await authService.reauthenticate(context: context)
    try await authService.deleteUser() // Retry operation
  }
}

do {
  try await authService.updatePassword(to: newPassword)
} catch let error as AuthServiceError {
  if case .emailReauthenticationRequired(let context) = error {
    // Show your password prompt UI
    let password = await promptUserForPassword()
    let credential = EmailAuthProvider.credential(
      withEmail: context.email,
      password: password
    )
    try await authService.reauthenticate(with: credential)
    try await authService.updatePassword(to: newPassword) // Retry
  }
}

do {
  try await authService.deleteUser()
} catch let error as AuthServiceError {
  if case .phoneReauthenticationRequired(let context) = error {
    // Send verification code
    let verificationId = try await authService.verifyPhoneNumber(
      phoneNumber: context.phoneNumber
    )
    // Show your SMS code input UI
    let code = await promptUserForSMSCode()
    let credential = PhoneAuthProvider.provider().credential(
      withVerificationID: verificationId,
      verificationCode: code
    )
    try await authService.reauthenticate(with: credential)
    try await authService.deleteUser() // Retry
  }
}

do {
  try await authService.updatePassword(to: newPassword)
} catch let error as AuthServiceError {
  if case .emailLinkReauthenticationRequired(let context) = error {
    // Send verification email
    try await authService.sendEmailSignInLink(
      email: context.email,
      isReauth: true
    )
    // Show your "Check your email" UI
    await showCheckEmailUI()
    // When user taps the link, it opens your app with a URL
    // Handle it in your URL handler:
    // try await authService.handleSignInLink(url: url)
    // The handleSignInLink method automatically completes reauthentication
    try await authService.updatePassword(to: newPassword) // Retry
  }
}

import FirebaseAuthSwiftUI
import FirebaseOAuthSwiftUI
import SwiftUI

struct ContentView: View {
  let authService: AuthService

  init() {
    let configuration = AuthConfiguration()
    
    authService = AuthService(configuration: configuration)
      .withOAuthSignIn(
        OAuthProviderSwift(
          providerId: "oidc.line",  // LINE OIDC provider
          scopes: ["profile", "openid", "email"],  // LINE requires these scopes
          displayName: "Sign in with LINE",
          buttonIcon: Image("line-logo"),
          buttonBackgroundColor: .green,
          buttonForegroundColor: .white
        )
      )
      .withOAuthSignIn(
        OAuthProviderSwift(
          providerId: "oidc.custom-provider",
          scopes: ["profile", "openid"],
          displayName: "Sign in with Custom",
          buttonIcon: Image(systemName: "person.circle"),
          buttonBackgroundColor: .purple,
          buttonForegroundColor: .white
        )
      )
  }

  var body: some View {
    AuthPickerView {
      Text("App Content")
    }
    .environment(authService)
  }
}