refactor: allow providers to use whatever sign-in methods they wish

FirebaseSwiftUI/FirebaseAppleSwiftUI/Sources/Services/AppleProviderAuthUI.swift

@@ -114,7 +114,7 @@ extension AuthenticateWithAppleDialog: ASAuthorizationControllerDelegate {
 
 // MARK: - Apple Provider Swift
 
-public class AppleProviderSwift: AuthProviderSwift {
+public class AppleProviderSwift: CredentialAuthProviderSwift {
   public let scopes: [ASAuthorization.Scope]
   let providerId = "apple.com"
 
@@ -140,15 +140,15 @@ public class AppleProviderSwift: AuthProviderSwift {
 }
 
 public class AppleProviderAuthUI: AuthProviderUI {
-  public var provider: AuthProviderSwift
+  private let typedProvider: AppleProviderSwift
+  public var provider: AuthProviderSwift { typedProvider }
+  public let id: String = "apple.com"
 
-  public init(provider: AuthProviderSwift) {
-    self.provider = provider
+  public init(provider: AppleProviderSwift) {
+    typedProvider = provider
   }
 
-  public let id: String = "apple.com"
-
   @MainActor public func authButton() -> AnyView {
-    AnyView(SignInWithAppleButton(provider: provider))
+    AnyView(SignInWithAppleButton(provider: typedProvider))
   }
 }

FirebaseSwiftUI/FirebaseAppleSwiftUI/Sources/Views/SignInWithAppleButton.swift

@@ -20,8 +20,8 @@ import SwiftUI
 @MainActor
 public struct SignInWithAppleButton {
   @Environment(AuthService.self) private var authService
-  let provider: AuthProviderSwift
-  public init(provider: AuthProviderSwift) {
+  let provider: AppleProviderSwift
+  public init(provider: AppleProviderSwift) {
     self.provider = provider
   }
 }

FirebaseSwiftUI/FirebaseAuthSwiftUI/Sources/Services/AuthService.swift

@@ -17,7 +17,12 @@ import FirebaseAuthUIComponents
 import FirebaseCore
 import SwiftUI
 
-public protocol AuthProviderSwift {
+/// Base protocol for all authentication providers
+public protocol AuthProviderSwift {}
+
+/// Protocol for providers that can directly create an AuthCredential
+/// Used by Google, Apple, Twitter, Facebook, and OAuth providers
+public protocol CredentialAuthProviderSwift: AuthProviderSwift {
   @MainActor func createAuthCredential() async throws -> AuthCredential
 }
 
@@ -27,12 +32,6 @@ public protocol AuthProviderUI {
   var provider: AuthProviderSwift { get }
 }
 
-public protocol PhoneAuthProviderSwift: AuthProviderSwift {
-  @MainActor func verifyPhoneNumber(phoneNumber: String) async throws -> String
-  @MainActor func createAuthCredential(verificationId: String,
-                                       verificationCode: String) async throws -> AuthCredential
-}
-
 public enum AuthenticationState {
   case unauthenticated
   case authenticating
@@ -164,10 +163,6 @@ public final class AuthService {
 
   private var providers: [AuthProviderUI] = []
 
-  public var currentPhoneProvider: PhoneAuthProviderSwift? {
-    providers.compactMap { $0.provider as? PhoneAuthProviderSwift }.first
-  }
-
   public func registerProvider(providerWithButton: AuthProviderUI) {
     providers.append(providerWithButton)
   }
@@ -189,7 +184,7 @@ public final class AuthService {
     )
   }
 
-  public func signIn(_ provider: AuthProviderSwift) async throws -> SignInOutcome {
+  public func signIn(_ provider: CredentialAuthProviderSwift) async throws -> SignInOutcome {
     do {
       let credential = try await provider.createAuthCredential()
       let result = try await signIn(credentials: credential)
@@ -829,8 +824,15 @@ public extension AuthService {
       let password = try await passwordPrompt.confirmPassword()
       let credential = EmailAuthProvider.credential(withEmail: email, password: password)
       _ = try await user.reauthenticate(with: credential)
-    } else if let matchingProvider = providers.first(where: { $0.id == providerId }) {
-      let credential = try await matchingProvider.provider.createAuthCredential()
+    } else if providerId == PhoneAuthProviderID {
+      // Phone auth requires manual reauthentication via sign out and sign in otherwise it will take
+      // the user out of the existing flow
+      throw AuthServiceError.reauthenticationRequired(
+        "Phone authentication requires you to sign out and sign in again to continue"
+      )
+    } else if let matchingProvider = providers.first(where: { $0.id == providerId }),
+              let credentialProvider = matchingProvider.provider as? CredentialAuthProviderSwift {
+      let credential = try await credentialProvider.createAuthCredential()
       _ = try await user.reauthenticate(with: credential)
     } else {
       throw AuthServiceError.providerNotFound("No provider found for \(providerId)")

FirebaseSwiftUI/FirebaseAuthSwiftUI/Sources/Views/EnterPhoneNumberView.swift

@@ -48,11 +48,8 @@ struct EnterPhoneNumberView: View {
       Button(action: {
         Task {
           do {
-            guard let provider = authService.currentPhoneProvider else {
-              fatalError("No phone provider found")
-            }
             let fullPhoneNumber = selectedCountry.dialCode + phoneNumber
-            let id = try await provider.verifyPhoneNumber(phoneNumber: fullPhoneNumber)
+            let id = try await authService.verifyPhoneNumber(phoneNumber: fullPhoneNumber)
             authService.navigator.push(.enterVerificationCode(
               verificationID: id,
               fullPhoneNumber: fullPhoneNumber

FirebaseSwiftUI/FirebaseAuthSwiftUI/Sources/Views/EnterVerificationCodeView.swift

@@ -52,15 +52,10 @@ struct EnterVerificationCodeView: View {
         Button(action: {
           Task {
             do {
-              guard let provider = authService.currentPhoneProvider else {
-                fatalError("No phone provider found")
-              }
-              let credential = try await provider.createAuthCredential(
-                verificationId: verificationID,
+              try await authService.signInWithPhoneNumber(
+                verificationID: verificationID,
                 verificationCode: verificationCode
               )
-
-              _ = try await authService.signIn(credentials: credential)
               authService.navigator.clear()
             } catch {}
           }

FirebaseSwiftUI/FirebaseFacebookSwiftUI/Sources/Services/FacebookProviderAuthUI.swift

@@ -19,7 +19,7 @@ import FirebaseAuth
 import FirebaseAuthSwiftUI
 import SwiftUI
 
-public class FacebookProviderSwift: AuthProviderSwift {
+public class FacebookProviderSwift: CredentialAuthProviderSwift {
   let scopes: [String]
   let providerId = "facebook.com"
   private let loginManager = LoginManager()
@@ -119,14 +119,15 @@ public class FacebookProviderSwift: AuthProviderSwift {
 }
 
 public class FacebookProviderAuthUI: AuthProviderUI {
-  public var provider: AuthProviderSwift
+  private let typedProvider: FacebookProviderSwift
+  public var provider: AuthProviderSwift { typedProvider }
   public let id: String = "facebook.com"
 
-  public init(provider: AuthProviderSwift) {
-    self.provider = provider
+  public init(provider: FacebookProviderSwift) {
+    typedProvider = provider
   }
 
   @MainActor public func authButton() -> AnyView {
-    AnyView(SignInWithFacebookButton(facebookProvider: provider as! FacebookProviderSwift))
+    AnyView(SignInWithFacebookButton(facebookProvider: typedProvider))
   }
 }

FirebaseSwiftUI/FirebaseGoogleSwiftUI/Sources/Services/GoogleProviderAuthUI.swift

@@ -19,7 +19,7 @@ import GoogleSignIn
 import GoogleSignInSwift
 import SwiftUI
 
-public class GoogleProviderSwift: AuthProviderSwift {
+public class GoogleProviderSwift: CredentialAuthProviderSwift {
   let scopes: [String]
   let clientID: String
   let providerId = "google.com"
@@ -71,14 +71,15 @@ public class GoogleProviderSwift: AuthProviderSwift {
 }
 
 public class GoogleProviderAuthUI: AuthProviderUI {
-  public var provider: AuthProviderSwift
+  private let typedProvider: GoogleProviderSwift
+  public var provider: AuthProviderSwift { typedProvider }
   public let id: String = "google.com"
 
-  public init(provider: AuthProviderSwift) {
-    self.provider = provider
+  public init(provider: GoogleProviderSwift) {
+    typedProvider = provider
   }
 
   @MainActor public func authButton() -> AnyView {
-    AnyView(SignInWithGoogleButton(googleProvider: provider))
+    AnyView(SignInWithGoogleButton(googleProvider: typedProvider))
   }
 }

FirebaseSwiftUI/FirebaseGoogleSwiftUI/Sources/Views/SignInWithGoogleButton.swift

@@ -26,9 +26,9 @@ import SwiftUI
 @MainActor
 public struct SignInWithGoogleButton {
   @Environment(AuthService.self) private var authService
-  let googleProvider: AuthProviderSwift
+  let googleProvider: GoogleProviderSwift
 
-  public init(googleProvider: AuthProviderSwift) {
+  public init(googleProvider: GoogleProviderSwift) {
     self.googleProvider = googleProvider
   }
 }

FirebaseSwiftUI/FirebaseOAuthSwiftUI/Sources/Services/OAuthProviderSwift.swift

@@ -18,7 +18,7 @@ import FirebaseCore
 import SwiftUI
 
 /// Configuration for a generic OAuth provider
-public class OAuthProviderSwift: AuthProviderSwift {
+public class OAuthProviderSwift: CredentialAuthProviderSwift {
   public let providerId: String
   public let scopes: [String]
   public let customParameters: [String: String]
@@ -116,20 +116,18 @@ public class OAuthProviderSwift: AuthProviderSwift {
 }
 
 public class OAuthProviderAuthUI: AuthProviderUI {
-  public var provider: AuthProviderSwift
+  private let typedProvider: OAuthProviderSwift
+  public var provider: AuthProviderSwift { typedProvider }
 
-  public init(provider: AuthProviderSwift) {
-    self.provider = provider
+  public init(provider: OAuthProviderSwift) {
+    typedProvider = provider
   }
 
   public var id: String {
-    guard let oauthProvider = provider as? OAuthProviderSwift else {
-      return "oauth.unknown"
-    }
-    return oauthProvider.providerId
+    return typedProvider.providerId
   }
 
   @MainActor public func authButton() -> AnyView {
-    AnyView(GenericOAuthButton(provider: provider))
+    AnyView(GenericOAuthButton(provider: typedProvider))
   }
 }

FirebaseSwiftUI/FirebaseOAuthSwiftUI/Sources/Views/GenericOAuthButton.swift

@@ -20,35 +20,28 @@ import SwiftUI
 @MainActor
 public struct GenericOAuthButton {
   @Environment(AuthService.self) private var authService
-  let provider: AuthProviderSwift
-  public init(provider: AuthProviderSwift) {
+  let provider: OAuthProviderSwift
+  public init(provider: OAuthProviderSwift) {
     self.provider = provider
   }
 }
 
 extension GenericOAuthButton: View {
   public var body: some View {
-    guard let oauthProvider = provider as? OAuthProviderSwift else {
-      return AnyView(
-        Text(authService.string.invalidOAuthProviderError)
-          .foregroundColor(.red)
-      )
-    }
-
     // Create custom style from provider configuration
     var resolvedStyle: ProviderStyle {
       ProviderStyle(
-        icon: oauthProvider.buttonIcon,
-        backgroundColor: oauthProvider.buttonBackgroundColor,
-        contentColor: oauthProvider.buttonForegroundColor
+        icon: provider.buttonIcon,
+        backgroundColor: provider.buttonBackgroundColor,
+        contentColor: provider.buttonForegroundColor
       )
     }
 
     return AnyView(
       AuthProviderButton(
-        label: oauthProvider.displayName,
+        label: provider.displayName,
         style: resolvedStyle,
-        accessibilityId: "sign-in-with-\(oauthProvider.providerId)-button"
+        accessibilityId: "sign-in-with-\(provider.providerId)-button"
       ) {
         Task {
           try? await authService.signIn(provider)

FirebaseSwiftUI/FirebasePhoneAuthSwiftUI/Sources/Services/PhoneAuthProviderAuthUI.swift

@@ -12,49 +12,24 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-@preconcurrency import FirebaseAuth
 import FirebaseAuthSwiftUI
 import SwiftUI
 
-public typealias VerificationID = String
-
-public class PhoneProviderSwift: PhoneAuthProviderSwift {
+/// Simple provider marker for phone authentication
+public class PhoneProviderSwift: AuthProviderSwift {
   public init() {}
-
-  @MainActor public func verifyPhoneNumber(phoneNumber: String) async throws -> VerificationID {
-    return try await withCheckedThrowingContinuation { continuation in
-      PhoneAuthProvider.provider()
-        .verifyPhoneNumber(phoneNumber, uiDelegate: nil) { verificationID, error in
-          if let error = error {
-            continuation.resume(throwing: error)
-            return
-          }
-          continuation.resume(returning: verificationID!)
-        }
-    }
-  }
-
-  @MainActor public func createAuthCredential() async throws -> AuthCredential {
-    fatalError("Not implemented")
-  }
-
-  @MainActor public func createAuthCredential(verificationId: String,
-                                              verificationCode: String) async throws
-    -> AuthCredential {
-    return PhoneAuthProvider.provider()
-      .credential(withVerificationID: verificationId, verificationCode: verificationCode)
-  }
 }
 
 public class PhoneAuthProviderAuthUI: AuthProviderUI {
-  public var provider: AuthProviderSwift
+  private let typedProvider: PhoneProviderSwift
+  public var provider: AuthProviderSwift { typedProvider }
   public let id: String = "phone"
 
-  public init(provider: PhoneAuthProviderSwift? = nil) {
-    self.provider = provider ?? PhoneProviderSwift()
+  public init() {
+    typedProvider = PhoneProviderSwift()
   }
 
   @MainActor public func authButton() -> AnyView {
-    AnyView(PhoneAuthButtonView(phoneProvider: provider as! PhoneAuthProviderSwift))
+    AnyView(PhoneAuthButtonView())
   }
 }

FirebaseSwiftUI/FirebasePhoneAuthSwiftUI/Sources/Views/PhoneAuthButtonView.swift

@@ -20,11 +20,8 @@ import SwiftUI
 @MainActor
 public struct PhoneAuthButtonView {
   @Environment(AuthService.self) private var authService
-  let phoneProvider: PhoneAuthProviderSwift
 
-  public init(phoneProvider: PhoneAuthProviderSwift) {
-    self.phoneProvider = phoneProvider
-  }
+  public init() {}
 }
 
 extension PhoneAuthButtonView: View {
@@ -41,7 +38,6 @@ extension PhoneAuthButtonView: View {
 
 #Preview {
   FirebaseOptions.dummyConfigurationForPreview()
-  let phoneProvider = PhoneProviderSwift()
-  return PhoneAuthButtonView(phoneProvider: phoneProvider)
+  return PhoneAuthButtonView()
     .environment(AuthService())
 }

FirebaseSwiftUI/FirebaseTwitterSwiftUI/Sources/Services/TwitterProviderAuthUI.swift

@@ -17,7 +17,7 @@ import FirebaseAuthSwiftUI
 import FirebaseCore
 import SwiftUI
 
-public class TwitterProviderSwift: AuthProviderSwift {
+public class TwitterProviderSwift: CredentialAuthProviderSwift {
   public let scopes: [String]
   let providerId = "twitter.com"
 
@@ -45,15 +45,15 @@ public class TwitterProviderSwift: AuthProviderSwift {
 }
 
 public class TwitterProviderAuthUI: AuthProviderUI {
-  public var provider: AuthProviderSwift
+  private let typedProvider: TwitterProviderSwift
+  public var provider: AuthProviderSwift { typedProvider }
+  public let id: String = "twitter.com"
 
-  public init(provider: AuthProviderSwift) {
-    self.provider = provider
+  public init(provider: TwitterProviderSwift) {
+    typedProvider = provider
   }
 
-  public let id: String = "twitter.com"
-
   @MainActor public func authButton() -> AnyView {
-    AnyView(SignInWithTwitterButton(provider: provider))
+    AnyView(SignInWithTwitterButton(provider: typedProvider))
   }
 }