feat(firebaseai): hybrid with system default model

packages/firebase_ai/firebase_ai/android/build.gradle

@@ -47,3 +47,9 @@ android {
         disable 'InvalidPackage'
     }
 }
+
+dependencies {
+    implementation "com.google.mlkit:genai-prompt:1.0.0-beta2"
+    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:1.7.3"
+}
+

packages/firebase_ai/firebase_ai/android/local-config.gradle

@@ -1,6 +1,6 @@
 ext {
     compileSdk=34
-    minSdk=23
+    minSdk=26
     targetSdk=34
     javaVersion = JavaVersion.toVersion(17)
     androidGradlePluginVersion = '8.3.0'

packages/firebase_ai/firebase_ai/android/src/main/kotlin/io/flutter/plugins/firebase/ai/FirebaseAIPlugin.kt

@@ -32,6 +32,11 @@ class FirebaseAIPlugin : FlutterPlugin, MethodChannel.MethodCallHandler {
         context = binding.applicationContext
         channel = MethodChannel(binding.binaryMessenger, "plugins.flutter.io/firebase_ai")
         channel.setMethodCallHandler(this)
+
+        LocalAIApi.setUp(binding.binaryMessenger, LocalAIImpl())
+
+        val eventChannel = io.flutter.plugin.common.EventChannel(binding.binaryMessenger, "dev.flutter.pigeon.firebase_ai.LocalAIApi.stream")
+        eventChannel.setStreamHandler(LocalAIStreamHandler.shared)
     }
 
     override fun onDetachedFromEngine(binding: FlutterPlugin.FlutterPluginBinding) {
@@ -99,3 +104,26 @@ class FirebaseAIPlugin : FlutterPlugin, MethodChannel.MethodCallHandler {
         private const val TAG = "FirebaseAIPlugin"
     }
 }
+
+class LocalAIStreamHandler : io.flutter.plugin.common.EventChannel.StreamHandler {
+    companion object {
+        val shared = LocalAIStreamHandler()
+    }
+    private var eventSink: io.flutter.plugin.common.EventChannel.EventSink? = null
+
+    override fun onListen(arguments: Any?, events: io.flutter.plugin.common.EventChannel.EventSink?) {
+        eventSink = events
+    }
+
+    override fun onCancel(arguments: Any?) {
+        eventSink = null
+    }
+
+    fun sendEvent(event: String) {
+        eventSink?.success(event)
+    }
+
+    fun closeStream() {
+        eventSink?.endOfStream()
+    }
+}

packages/firebase_ai/firebase_ai/android/src/main/kotlin/io/flutter/plugins/firebase/ai/GeneratedLocalAI.kt

@@ -0,0 +1,165 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// Autogenerated from Pigeon (v26.3.4), do not edit directly.
+// See also: https://pub.dev/packages/pigeon
+@file:Suppress("UNCHECKED_CAST", "ArrayInDataClass")
+
+package io.flutter.plugins.firebase.ai
+
+import android.util.Log
+import io.flutter.plugin.common.BasicMessageChannel
+import io.flutter.plugin.common.BinaryMessenger
+import io.flutter.plugin.common.EventChannel
+import io.flutter.plugin.common.MessageCodec
+import io.flutter.plugin.common.StandardMethodCodec
+import io.flutter.plugin.common.StandardMessageCodec
+import java.io.ByteArrayOutputStream
+import java.nio.ByteBuffer
+private object GeneratedLocalAIPigeonUtils {
+
+  fun wrapResult(result: Any?): List<Any?> {
+    return listOf(result)
+  }
+
+  fun wrapError(exception: Throwable): List<Any?> {
+    return if (exception is FlutterError) {
+      listOf(
+        exception.code,
+        exception.message,
+        exception.details
+      )
+    } else {
+      listOf(
+        exception.javaClass.simpleName,
+        exception.toString(),
+        "Cause: " + exception.cause + ", Stacktrace: " + Log.getStackTraceString(exception)
+      )
+    }
+  }
+}
+
+/**
+ * Error class for passing custom error details to Flutter via a thrown PlatformException.
+ * @property code The error code.
+ * @property message The error message.
+ * @property details The error details. Must be a datatype supported by the api codec.
+ */
+class FlutterError (
+  val code: String,
+  override val message: String? = null,
+  val details: Any? = null
+) : RuntimeException()
+private open class GeneratedLocalAIPigeonCodec : StandardMessageCodec() {
+  override fun readValueOfType(type: Byte, buffer: ByteBuffer): Any? {
+    return     super.readValueOfType(type, buffer)
+  }
+  override fun writeValue(stream: ByteArrayOutputStream, value: Any?)   {
+    super.writeValue(stream, value)
+  }
+}
+
+
+/** Generated interface from Pigeon that represents a handler of messages from Flutter. */
+interface LocalAIApi {
+  fun isAvailable(callback: (Result<Boolean>) -> Unit)
+  fun generateContent(prompt: String, callback: (Result<String>) -> Unit)
+  fun warmup(callback: (Result<Unit>) -> Unit)
+  fun startStreaming(prompt: String, callback: (Result<Unit>) -> Unit)
+
+  companion object {
+    /** The codec used by LocalAIApi. */
+    val codec: MessageCodec<Any?> by lazy {
+      GeneratedLocalAIPigeonCodec()
+    }
+    /** Sets up an instance of `LocalAIApi` to handle messages through the `binaryMessenger`. */
+    @JvmOverloads
+    fun setUp(binaryMessenger: BinaryMessenger, api: LocalAIApi?, messageChannelSuffix: String = "") {
+      val separatedMessageChannelSuffix = if (messageChannelSuffix.isNotEmpty()) ".$messageChannelSuffix" else ""
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.firebase_ai.LocalAIApi.isAvailable$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { _, reply ->
+            api.isAvailable{ result: Result<Boolean> ->
+              val error = result.exceptionOrNull()
+              if (error != null) {
+                reply.reply(GeneratedLocalAIPigeonUtils.wrapError(error))
+              } else {
+                val data = result.getOrNull()
+                reply.reply(GeneratedLocalAIPigeonUtils.wrapResult(data))
+              }
+            }
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.firebase_ai.LocalAIApi.generateContent$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val promptArg = args[0] as String
+            api.generateContent(promptArg) { result: Result<String> ->
+              val error = result.exceptionOrNull()
+              if (error != null) {
+                reply.reply(GeneratedLocalAIPigeonUtils.wrapError(error))
+              } else {
+                val data = result.getOrNull()
+                reply.reply(GeneratedLocalAIPigeonUtils.wrapResult(data))
+              }
+            }
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.firebase_ai.LocalAIApi.warmup$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { _, reply ->
+            api.warmup{ result: Result<Unit> ->
+              val error = result.exceptionOrNull()
+              if (error != null) {
+                reply.reply(GeneratedLocalAIPigeonUtils.wrapError(error))
+              } else {
+                reply.reply(GeneratedLocalAIPigeonUtils.wrapResult(null))
+              }
+            }
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+      run {
+        val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.firebase_ai.LocalAIApi.startStreaming$separatedMessageChannelSuffix", codec)
+        if (api != null) {
+          channel.setMessageHandler { message, reply ->
+            val args = message as List<Any?>
+            val promptArg = args[0] as String
+            api.startStreaming(promptArg) { result: Result<Unit> ->
+              val error = result.exceptionOrNull()
+              if (error != null) {
+                reply.reply(GeneratedLocalAIPigeonUtils.wrapError(error))
+              } else {
+                reply.reply(GeneratedLocalAIPigeonUtils.wrapResult(null))
+              }
+            }
+          }
+        } else {
+          channel.setMessageHandler(null)
+        }
+      }
+    }
+  }
+}

packages/firebase_ai/firebase_ai/android/src/main/kotlin/io/flutter/plugins/firebase/ai/LocalAIImpl.kt

@@ -0,0 +1,86 @@
+// Copyright 2026 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package io.flutter.plugins.firebase.ai
+
+import com.google.mlkit.genai.prompt.Generation
+import com.google.mlkit.genai.prompt.GenerateContentRequest
+import com.google.mlkit.genai.prompt.TextPart
+import com.google.mlkit.genai.common.FeatureStatus
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.flow.catch
+
+class LocalAIImpl : LocalAIApi {
+  private val coroutineScope = CoroutineScope(Dispatchers.Main)
+  private val mlkitModel by lazy { Generation.getClient() }
+
+  override fun isAvailable(callback: (Result<Boolean>) -> Unit) {
+    coroutineScope.launch {
+      try {
+        val status = mlkitModel.checkStatus()
+        callback(Result.success(status == FeatureStatus.AVAILABLE))
+      } catch (e: Exception) {
+        callback(Result.success(false))
+      }
+    }
+  }
+
+  override fun generateContent(prompt: String, callback: (Result<String>) -> Unit) {
+    coroutineScope.launch {
+      try {
+        val request = GenerateContentRequest.builder(TextPart(prompt)).build()
+        val response = mlkitModel.generateContent(request)
+        val text = response.candidates.firstOrNull()?.text ?: ""
+        callback(Result.success(text))
+      } catch (e: Exception) {
+        callback(Result.failure(e))
+      }
+    }
+  }
+
+  override fun warmup(callback: (Result<Unit>) -> Unit) {
+    coroutineScope.launch {
+      try {
+        mlkitModel.warmup()
+        callback(Result.success(Unit))
+      } catch (e: Exception) {
+        callback(Result.failure(e))
+      }
+    }
+  }
+
+  override fun startStreaming(prompt: String, callback: (Result<Unit>) -> Unit) {
+    coroutineScope.launch {
+      try {
+        val request = GenerateContentRequest.builder(TextPart(prompt)).build()
+        mlkitModel.generateContentStream(request)
+          .catch { e ->
+            callback(Result.failure(e))
+          }
+          .collect { chunk ->
+            val text = chunk.candidates.firstOrNull()?.text ?: ""
+            if (text.isNotEmpty()) {
+              LocalAIStreamHandler.shared.sendEvent(text)
+            }
+          }
+        LocalAIStreamHandler.shared.closeStream()
+        callback(Result.success(Unit))
+      } catch (e: Exception) {
+        callback(Result.failure(e))
+      }
+    }
+  }
+}

packages/firebase_ai/firebase_ai/example/android/app/build.gradle.kts

@@ -1,5 +1,8 @@
 plugins {
     id("com.android.application")
+    // START: FlutterFire Configuration
+    id("com.google.gms.google-services")
+    // END: FlutterFire Configuration
     id("kotlin-android")
     // The Flutter Gradle Plugin must be applied after the Android and Kotlin Gradle plugins.
     id("dev.flutter.flutter-gradle-plugin")
@@ -22,9 +25,7 @@ android {
     defaultConfig {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
         applicationId = "com.example.firebase_ai_example"
-        // You can update the following values to match your application needs.
-        // For more information, see: https://flutter.dev/to/review-gradle-config.
-        minSdk = flutter.minSdkVersion
+        minSdk = 26
         targetSdk = flutter.targetSdkVersion
         versionCode = flutter.versionCode
         versionName = flutter.versionName

packages/firebase_ai/firebase_ai/example/android/settings.gradle.kts

@@ -19,6 +19,9 @@ pluginManagement {
 plugins {
     id("dev.flutter.flutter-plugin-loader") version "1.0.0"
     id("com.android.application") version "8.9.1" apply false
+    // START: FlutterFire Configuration
+    id("com.google.gms.google-services") version("4.3.15") apply false
+    // END: FlutterFire Configuration
     id("org.jetbrains.kotlin.android") version "2.1.0" apply false
 }
 

packages/firebase_ai/firebase_ai/example/lib/main.dart

@@ -19,27 +19,28 @@ import 'package:firebase_core/firebase_core.dart';
 import 'package:flutter/material.dart';
 
 // Import after file is generated through flutterfire_cli.
-// import 'package:firebase_ai_example/firebase_options.dart';
+import 'package:firebase_ai_example/firebase_options.dart';
 
 import 'pages/bidi_page.dart';
 import 'pages/chat_page.dart';
 import 'pages/function_calling_page.dart';
+import 'pages/grounding_page.dart';
+import 'pages/hybrid_page.dart';
 import 'pages/image_generation_page.dart';
 import 'pages/image_prompt_page.dart';
 import 'pages/json_schema_page.dart';
 import 'pages/multimodal_page.dart';
 import 'pages/schema_page.dart';
 import 'pages/server_template_page.dart';
-import 'pages/grounding_page.dart';
 import 'pages/token_count_page.dart';
 
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
   // Enable this line instead once have the firebase_options.dart generated and
   // imported through flutterfire_cli.
-  // await Firebase.initializeApp(options: DefaultFirebaseOptions.currentPlatform);
-  await Firebase.initializeApp();
-  await FirebaseAuth.instance.signInAnonymously();
+  await Firebase.initializeApp(options: DefaultFirebaseOptions.currentPlatform);
+  // await Firebase.initializeApp();
+  // await FirebaseAuth.instance.signInAnonymously();
   runApp(const GenerativeAISample());
 }
 
@@ -180,6 +181,11 @@ class _HomeScreenState extends State<HomeScreen> {
           title: 'Grounding',
           useVertexBackend: useVertexBackend,
         );
+      case 11:
+        return HybridPage(
+          title: 'Hybrid Mode',
+          model: currentModel,
+        );
 
       default:
         // Fallback to the first page in case of an unexpected index
@@ -314,6 +320,13 @@ class _HomeScreenState extends State<HomeScreen> {
             label: 'Grounding',
             tooltip: 'Search & Maps Grounding',
           ),
+          BottomNavigationBarItem(
+            icon: Icon(
+              Icons.auto_awesome,
+            ),
+            label: 'Hybrid',
+            tooltip: 'Hybrid Mode',
+          ),
         ],
         currentIndex: _selectedIndex,
         onTap: _onItemTapped,