Vanira Flutter SDK — Scaffold

Status: Scaffold only. The protocol and session class are defined. Full implementation requires wiring flutter_webrtc into VaniraSession.

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Architecture

The Flutter SDK mirrors the TypeScript SDK's core layer exactly. The signaling protocol, DataChannel event schema, and state machine are identical. Only the runtime (Dart vs JavaScript) and platform APIs differ.

flutter-sdk/
  lib/
    src/
      vanira_session.dart   ← Core session — mirrors TypeScript WebRTCClient
    vanira_sdk.dart         ← Public export
  pubspec.yaml
  README.md

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TypeScript → Dart mapping

TypeScript (npm SDK)	Dart (Flutter SDK)
new RTCPeerConnection(config)	createPeerConnection(config) (flutter_webrtc)
navigator.mediaDevices.getUserMedia()	navigator.mediaDevices.getUserMedia() (flutter_webrtc)
pc.createDataChannel('control', {})	pc.createDataChannel('control', RTCDataChannelInit())
pc.createOffer()	await pc.createOffer({})
pc.setLocalDescription(offer)	await pc.setLocalDescription(offer)
pc.setRemoteDescription(answer)	await pc.setRemoteDescription(...)
pc.onConnectionState = handler	pc.onConnectionState.listen(handler)
pc.onIceGatheringState listener	pc.onIceGatheringState.listen(handler)
fetch(url, { method: 'POST', ... })	http.post(Uri.parse(url), body: jsonEncode(...))
JSON.stringify / JSON.parse	jsonEncode / jsonDecode (dart:convert)
new Audio() + srcObject	Not needed — flutter_webrtc routes audio automatically
setTimeout(fn, 5000)	Future.delayed(const Duration(seconds: 5), fn)
Promise / async-await	Future / async-await (same pattern)
onConnected callback	VoidCallback / Function()
onTranscription callback	Function(String text, bool isFinal)

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DataChannel protocol

The event schema is identical to the browser/RN SDK. Dart's jsonDecode produces Map<String, dynamic> which maps directly to the TypeScript interface.

Server → client events

event	payload fields	action
clearAudio	—	No-op (flutter_webrtc manages audio)
transcription	text, isFinal	Call onTranscription(text, isFinal)
mark	name	Log only
client_tool_call	tool_call_id, name, arguments	Send ack immediately, call onClientToolCall

Client → server events

method	event name	payload
sendToolResult(id, res)	client_tool_result	{ call_id, result }
sendContextUpdate(ctx)	client_context_update	{ data: { context } }
sendActionTrigger(name)	client_action_trigger	{ data: { action_name, data } }
triggerActionInterrupt()	action_interrupt	—

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Implementation steps

1. Add dependencies to pubspec.yaml

dependencies:
  flutter_webrtc: ^0.9.0
  http: ^1.2.0
  permission_handler: ^11.0.0

2. Request microphone permission

import 'package:permission_handler/permission_handler.dart';
await Permission.microphone.request();

3. Register globals (Android / iOS)

// In main.dart before runApp()
import 'package:flutter_webrtc/flutter_webrtc.dart';
// No explicit registerGlobals() needed in flutter_webrtc >= 0.9
// flutter_webrtc auto-initializes on first API call

4. Wire VaniraSession.connect()

Uncomment and implement all TODO blocks in lib/src/vanira_session.dart. Each TODO maps to a numbered step in the TypeScript SDK's connect() method.

5. HTTP signaling (already portable)

The signaling endpoint and JSON body are identical to the TypeScript SDK:

final response = await http.post(
  Uri.parse('$serverUrl/webrtc?agent=${agentId}_$callId'),
  headers: {'Content-Type': 'application/json'},
  body: jsonEncode({
    'offer': offer.toMap(),
    'agentId': agentId,
    'callId': callId,
  }),
);
final answer = jsonDecode(response.body)['answer'];

6. Distribution

Publish to pub.flutter-io.cn as vanira_sdk:

name: vanira_sdk
version: 0.0.1
homepage: https://vanira.io
repository: https://github.com/vanira-ai/flutter-sdk

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Known differences from browser/RN SDK

Topic	Browser / RN	Flutter
Audio output	new Audio() / native stack	Automatic via flutter_webrtc
playedStream event	Sent when audio.onended fires	Never sent — no onended equiv.
Screen share	Browser: getDisplayMedia(); RN: N/A	N/A — not supported
CDN distribution	<script> tag via unpkg	flutter pub add vanira_sdk
Widget	<vanira-convai> custom element	Flutter StatefulWidget
State management	React hooks / Redux	Riverpod / Provider / setState
Env vars	import.meta.env.VITE_*	flutter_dotenv or const String.fromEnvironment