Implement Firebase Google sign-in with enum-based auth contracts.

Refactor AuthService to use AuthProvider and User, add Firebase-backed auth wiring for login/manage flows, and fix app-level Google services configuration so Credential Manager sign-in works reliably.

Made-with: Cursor

sdk/src/main/kotlin/org/db3/airmq/sdk/auth/AuthService.kt

@@ -1,10 +1,11 @@
 package org.db3.airmq.sdk.auth
 
-import org.db3.airmq.sdk.auth.model.Auth
+import org.db3.airmq.sdk.auth.model.AuthProvider
+import org.db3.airmq.sdk.auth.model.User
 
 interface AuthService {
-    suspend fun getCurrentSession(): Auth?
+    suspend fun getCurrentSession(): User?
     suspend fun isAuthenticated(): Boolean
-    suspend fun signIn(provider: String, token: String? = null): Result<Auth>
+    suspend fun signIn(provider: AuthProvider, token: String): Result<User>
     suspend fun signOut(): Result<Unit>
 }

sdk/src/main/kotlin/org/db3/airmq/sdk/auth/AuthServiceImpl.kt

@@ -0,0 +1,60 @@
+package org.db3.airmq.sdk.auth
+
+import com.google.android.gms.tasks.Task
+import com.google.firebase.auth.FirebaseAuth
+import com.google.firebase.auth.FirebaseUser
+import com.google.firebase.auth.GoogleAuthProvider
+import javax.inject.Inject
+import javax.inject.Singleton
+import kotlin.coroutines.resume
+import kotlin.coroutines.resumeWithException
+import kotlinx.coroutines.suspendCancellableCoroutine
+import org.db3.airmq.sdk.auth.model.AuthProvider
+import org.db3.airmq.sdk.auth.model.User
+
+@Singleton
+class FirebaseAuthService @Inject constructor(
+    private val firebaseAuth: FirebaseAuth
+) : AuthService {
+
+    override suspend fun getCurrentSession(): User? = firebaseAuth.currentUser?.toUser()
+
+    override suspend fun isAuthenticated(): Boolean = firebaseAuth.currentUser != null
+
+    override suspend fun signIn(provider: AuthProvider, token: String): Result<User> = runCatching {
+        require(token.isNotBlank()) { "ID token is required for Google sign-in." }
+        when (provider) {
+            AuthProvider.GOOGLE -> signInWithGoogle(token)
+        }
+    }
+
+    override suspend fun signOut(): Result<Unit> = runCatching {
+        firebaseAuth.signOut()
+    }
+
+    private suspend fun signInWithGoogle(token: String): User {
+        val credential = GoogleAuthProvider.getCredential(token, null)
+        val authResult = firebaseAuth.signInWithCredential(credential).awaitResult()
+        val firebaseUser = authResult.user ?: error("Google sign-in completed without a Firebase user.")
+        return firebaseUser.toUser()
+    }
+
+    private fun FirebaseUser.toUser(): User = User(
+        userId = uid,
+        email = email,
+        displayName = displayName,
+        isAuthenticated = true
+    )
+}
+
+private suspend fun <T> Task<T>.awaitResult(): T = suspendCancellableCoroutine { continuation ->
+    addOnSuccessListener { result ->
+        continuation.resume(result)
+    }
+    addOnFailureListener { exception ->
+        continuation.resumeWithException(exception)
+    }
+    addOnCanceledListener {
+        continuation.cancel()
+    }
+}

sdk/src/main/kotlin/org/db3/airmq/sdk/auth/model/AuthProvider.kt

@@ -0,0 +1,5 @@
+package org.db3.airmq.sdk.auth.model
+
+enum class AuthProvider {
+    GOOGLE
+}

sdk/src/main/kotlin/org/db3/airmq/sdk/auth/model/User.kt

@@ -1,6 +1,6 @@
 package org.db3.airmq.sdk.auth.model
 
-data class Auth(
+data class User(
     val userId: String,
     val email: String?,
     val displayName: String?,

sdk/src/main/kotlin/org/db3/airmq/sdk/di/SDKModule.kt

@@ -1,12 +1,15 @@
 package org.db3.airmq.sdk.di
 
 import com.apollographql.apollo.ApolloClient
+import com.google.firebase.auth.FirebaseAuth
 import dagger.Binds
 import dagger.Module
 import dagger.Provides
 import dagger.hilt.InstallIn
 import dagger.hilt.components.SingletonComponent
 import javax.inject.Singleton
+import org.db3.airmq.sdk.auth.AuthService
+import org.db3.airmq.sdk.auth.FirebaseAuthService
 import org.db3.airmq.sdk.map.MapServiceImpl
 import org.db3.airmq.sdk.map.MapService
 import org.db3.airmq.sdk.settings.SettingsService
@@ -26,11 +29,19 @@ object SDKModule {
             .addInterceptor(ApolloLoggingInterceptor())
             .build()
     }
+
+    @Provides
+    @Singleton
+    fun provideFirebaseAuth(): FirebaseAuth = FirebaseAuth.getInstance()
 }
 
 @Module
 @InstallIn(SingletonComponent::class)
 abstract class SDKBindModule {
+    @Binds
+    @Singleton
+    abstract fun bindAuthService(impl: FirebaseAuthService): AuthService
+
     @Binds
     @Singleton
     abstract fun bindMapService(impl: MapServiceImpl): MapService