BIDI mini refactoring and new additions

firebase-ai/src/main/kotlin/com/google/firebase/ai/LiveGenerativeModel.kt

@@ -113,13 +113,17 @@ internal constructor(
       val receivedJson = JSON.parseToJsonElement(receivedJsonStr)
 
       return if (receivedJson is JsonObject && "setupComplete" in receivedJson) {
-        LiveSession(session = webSession, blockingDispatcher = blockingDispatcher)
+        LiveSession(
+          session = webSession,
+          blockingDispatcher = blockingDispatcher,
+          firebaseApp = controller.firebaseApp
+        )
       } else {
         webSession.close()
         throw ServiceConnectionHandshakeFailedException("Unable to connect to the server")
       }
     } catch (e: ClosedReceiveChannelException) {
-      throw ServiceConnectionHandshakeFailedException("Channel was closed by the server", e)
+      throw ServiceConnectionHandshakeFailedException("Error: Too many concurrent live requests", e)
     }
   }
 

firebase-ai/src/main/kotlin/com/google/firebase/ai/common/APIController.kt

@@ -97,7 +97,7 @@ internal constructor(
   private val requestOptions: RequestOptions,
   httpEngine: HttpClientEngine,
   private val apiClient: String,
-  private val firebaseApp: FirebaseApp,
+  internal val firebaseApp: FirebaseApp,
   private val appVersion: Int = 0,
   private val googleAppId: String,
   private val headerProvider: HeaderProvider?,

firebase-ai/src/main/kotlin/com/google/firebase/ai/type/Exceptions.kt

@@ -219,6 +219,10 @@ public class AudioRecordInitializationFailedException(message: String) :
 public class ServiceConnectionHandshakeFailedException(message: String, cause: Throwable? = null) :
   FirebaseAIException(message, cause)
 
+/** The request is missing a permission that is required to perform the requested operation. */
+public class PermissionMissingException(message: String, cause: Throwable? = null) :
+  FirebaseAIException(message, cause)
+
 /** Catch all case for exceptions not explicitly expected. */
 public class UnknownException internal constructor(message: String, cause: Throwable? = null) :
   FirebaseAIException(message, cause)

firebase-ai/src/main/kotlin/com/google/firebase/ai/type/LiveSession.kt

@@ -17,10 +17,13 @@
 package com.google.firebase.ai.type
 
 import android.Manifest.permission.RECORD_AUDIO
+import android.content.pm.PackageManager
 import android.media.AudioFormat
 import android.media.AudioTrack
 import android.util.Log
 import androidx.annotation.RequiresPermission
+import androidx.core.content.ContextCompat
+import com.google.firebase.FirebaseApp
 import com.google.firebase.ai.common.JSON
 import com.google.firebase.ai.common.util.CancelledCoroutineScope
 import com.google.firebase.ai.common.util.accumulateUntil
@@ -58,7 +61,8 @@ public class LiveSession
 internal constructor(
   private val session: ClientWebSocketSession,
   @Blocking private val blockingDispatcher: CoroutineContext,
-  private var audioHelper: AudioHelper? = null
+  private var audioHelper: AudioHelper? = null,
+  private val firebaseApp: FirebaseApp,
 ) {
   /**
    * Coroutine scope that we batch data on for [startAudioConversation].
@@ -93,6 +97,14 @@ internal constructor(
   public suspend fun startAudioConversation(
     functionCallHandler: ((FunctionCallPart) -> FunctionResponsePart)? = null
   ) {
+
+    val context = firebaseApp.applicationContext
+    if (
+      ContextCompat.checkSelfPermission(context, RECORD_AUDIO) != PackageManager.PERMISSION_GRANTED
+    ) {
+      throw PermissionMissingException("Audio access not provided by the user")
+    }
+
     FirebaseAIException.catchAsync {
       if (scope.isActive) {
         Log.w(
@@ -131,6 +143,12 @@ internal constructor(
     }
   }
 
+  /** Indicates whether the underlying websocket connection is active. */
+  public fun isActive(): Boolean = session.isActive
+
+  /** Indicates whether an audio conversation is being used for this session object. */
+  public fun isAudioConversationRunning(): Boolean = (audioHelper != null)
+
   /**
    * Receives responses from the model for both streaming and standard requests.
    *