refactor: move closer to preliminary design

Author: russellwheatley

FirebaseSwiftUI/FirebaseAuthSwiftUI/Sources/FirebaseAuthSwiftUI/FUIAuth.swift

@@ -0,0 +1,71 @@
+@preconcurrency import FirebaseAuth
+import SwiftUI
+
+public enum AuthenticationProvider {
+  case email
+  case google
+}
+
+public enum AuthenticationOperationType: String {
+  case signIn
+  case signUp
+  case deleteAccount
+}
+
+public enum AuthenticationState {
+  case unauthenticated
+  case authenticating
+  case authenticated
+}
+
+@MainActor
+@Observable
+public final class AuthEnvironment {
+  public static let shared = AuthEnvironment()
+
+  var currentUser: User?
+
+  private init() {
+    setupAuthenticationListener()
+  }
+
+  deinit {
+    if let handle = authStateHandle {
+      Auth.auth().removeStateDidChangeListener(handle)
+      authStateHandle = nil
+    }
+  }
+
+  public var authenticationState: AuthenticationState = .unauthenticated
+
+  private func setupAuthenticationListener() {
+    authStateHandle = Auth.auth().addStateDidChangeListener { [weak self] _, user in
+      self?.currentUser = user
+      self?.updateAuthenticationState()
+    }
+  }
+
+  private nonisolated(unsafe) var authStateHandle: AuthStateDidChangeListenerHandle? {
+    willSet {
+      if let handle = authStateHandle {
+        Auth.auth().removeStateDidChangeListener(handle)
+      }
+    }
+  }
+
+  func updateAuthenticationState() {
+    authenticationState =
+      (currentUser == nil || currentUser?.isAnonymous == true)
+        ? .unauthenticated
+        : .authenticated
+  }
+
+  public func signOut() throws {
+    try Auth.auth().signOut()
+  }
+
+  func signIn(with credentials: AuthCredential) async throws {
+    try await Auth.auth().signIn(with: credentials)
+    updateAuthenticationState()
+  }
+}

FirebaseSwiftUI/FirebaseAuthSwiftUI/Sources/FirebaseAuthSwiftUI/FUIAuthProvider.swift

@@ -0,0 +1,29 @@
+@preconcurrency import FirebaseAuth
+import SwiftUI
+
+@MainActor
+class EmailAuthProvider {
+  @Environment(AuthEnvironment.self) private var authEnvironment
+
+  public init() {}
+
+  func signIn(withEmail email: String, password: String) async throws {
+    authEnvironment.authenticationState = .authenticating
+    do {
+      try await Auth.auth().createUser(withEmail: email, password: password)
+    } catch {
+      authEnvironment.authenticationState = .unauthenticated
+      throw error
+    }
+  }
+
+  func signUp(withEmail email: String, password: String) async throws {
+    authEnvironment.authenticationState = .authenticating
+    do {
+      try await Auth.auth().createUser(withEmail: email, password: password)
+    } catch {
+      authEnvironment.authenticationState = .unauthenticated
+      throw error
+    }
+  }
+}

FirebaseSwiftUI/FirebaseAuthSwiftUI/Sources/FirebaseAuthSwiftUI/FUIAuthState.swift

@@ -0,0 +1,28 @@
+import FirebaseAuth
+import SwiftUI
+
+enum AuthenticationFlow {
+  case login
+  case signUp
+}
+
+public struct AuthenticationScreen {
+  @Environment(AuthEnvironment.self) private var authEnvironment
+
+  @State private var flow: AuthenticationFlow = .login
+
+  private func switchFlow() {
+    flow = flow == .login ? .signUp : .login
+    errorMessage = ""
+  }
+
+  @State private var errorMessage = ""
+}
+
+extension AuthenticationScreen: View {
+  public var body: some View {
+    VStack {
+      Text("Authentication screen")
+    }
+  }
+}

FirebaseSwiftUI/FirebaseAuthSwiftUI/Sources/FirebaseAuthSwiftUI/Services/AuthEnvironment.swift

@@ -0,0 +1,8 @@
+//
+//  EmailPasswordView.swift
+//  FirebaseUI
+//
+//  Created by Russell Wheatley on 20/03/2025.
+//
+
+import Foundation