feat: embed a Flutter G4F client with Cronet, cookie jar, and origin WebView

Port the Oracle off the Python g4f container onto on-device providers: Chromium HTTP via Cronet, a shared cookie session, IterList retry, hosted OpenAI-compat aggregators, and same-origin WebView fallbacks instead of CORS fetch.
2026-09-01 22:05:38 +05:00
parent f3e7412cf9
commit fbf04d90db
49 changed files with 4856 additions and 92 deletions
@@ -0,0 +1,90 @@
+import 'dart:convert';
+import 'package:http/http.dart' as http;
+import '../http_client.dart';
+import '../http_util.dart';
+import '../models.dart';
+import '../sse.dart';
+import 'base_provider.dart';
+
+/// OpenAI-compatible `/v1/chat/completions` client used by several free proxies.
+class OpenAiCompatProvider extends BaseProvider {
+  OpenAiCompatProvider({
+    required this.providerName,
+    required this.apiBase,
+    required this.fallbackModel,
+    List<String>? supportedModels,
+    this.apiKey,
+    this.extraHeaders = const {},
+  }) : supportedModels = supportedModels ?? [fallbackModel];
+
+  final String providerName;
+  final String apiBase;
+  final String fallbackModel;
+  final List<String> supportedModels;
+  final String? apiKey;
+  final Map<String, String> extraHeaders;
+
+  @override
+  String get name => providerName;
+
+  @override
+  bool get working => true;
+
+  @override
+  List<String> get models => supportedModels;
+
+  @override
+  String get defaultModel => fallbackModel;
+
+  String get chatUrl {
+    final base = apiBase.endsWith('/') ? apiBase.substring(0, apiBase.length - 1) : apiBase;
+    if (base.endsWith('/chat/completions')) return base;
+    return '$base/chat/completions';
+  }
+
+  @override
+  Stream<String> createAsyncGenerator(
+    String model,
+    List<Message> messages, {
+    bool stream = false,
+  }) async* {
+    final payload = <String, dynamic>{
+      'model': models.contains(model) ? model : defaultModel,
+      'messages': toOpenAiMessages(messages),
+      'stream': false,
+      'temperature': 0.8,
+    };
+
+    final headers = browserHeaders(
+      contentType: 'application/json',
+      accept: 'application/json',
+      extra: {
+        if (apiKey != null && apiKey!.isNotEmpty) 'Authorization': 'Bearer $apiKey',
+        ...extraHeaders,
+      },
+    );
+
+    final req = http.Request('POST', Uri.parse(chatUrl));
+    req.headers.addAll(headers);
+    req.body = jsonEncode(payload);
+
+    final response = await g4fHttp.send(req).timeout(requestTimeout);
+    if (response.statusCode < 200 || response.statusCode >= 300) {
+      final err = await response.stream.bytesToString();
+      throw Exception(
+        '$name returned ${response.statusCode}: ${err.substring(0, err.length.clamp(0, 240))}',
+      );
+    }
+
+    final body = utf8.decode(await response.stream.toBytes());
+    final fromJson = extractOpenAiMessage(body);
+    final fromSse = extractAllSseContent(body).join();
+    final text = (fromJson != null && looksLikeModelOutput(fromJson))
+        ? fromJson
+        : fromSse;
+    if (!looksLikeModelOutput(text)) {
+      throw Exception('$name returned unusable body');
+    }
+    yield text;
+  }
+}