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 +1,124 @@
+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';
+
+class Pollinations extends BaseProvider {
+  @override
+  String get name => 'Pollinations';
+
+  @override
+  bool get working => true;
+
+  @override
+  List<String> get models => [
+        'openai-fast',
+        'openai',
+        'deepseek',
+        G4FModels.gpt4o,
+        G4FModels.mistral,
+        G4FModels.llama3,
+        G4FModels.qwen,
+      ];
+
+  @override
+  String get defaultModel => 'openai-fast';
+
+  static const _getBase = 'https://text.pollinations.ai';
+  static const _postUrl = 'https://gen.pollinations.ai/v1/chat/completions';
+
+  String _resolveModel(String model) {
+    switch (model) {
+      case G4FModels.gpt4o:
+      case G4FModels.gpt4oMini:
+      case G4FModels.gpt4:
+        return 'openai-fast';
+      case G4FModels.mistral:
+      case G4FModels.llama3:
+      case G4FModels.qwen:
+        return 'openai-fast';
+      default:
+        return models.contains(model) ? model : defaultModel;
+    }
+  }
+
+  @override
+  Stream<String> createAsyncGenerator(
+    String model,
+    List<Message> messages, {
+    bool stream = false,
+  }) async* {
+    final resolved = _resolveModel(model);
+    try {
+      await for (final chunk in _getPrompt(resolved, messages, stream: stream)) {
+        yield chunk;
+      }
+      return;
+    } catch (_) {
+      await for (final chunk in _postChat(resolved, messages, stream: stream)) {
+        yield chunk;
+      }
+    }
+  }
+
+  Stream<String> _postChat(
+    String model,
+    List<Message> messages, {
+    required bool stream,
+  }) async* {
+    final req = http.Request('POST', Uri.parse(_postUrl));
+    req.headers.addAll(browserHeaders(
+      contentType: 'application/json',
+      accept: stream ? 'text/event-stream' : 'application/json',
+    ));
+    req.body = jsonEncode({
+      'model': model,
+      'messages': toOpenAiMessages(messages),
+      'stream': false, // anonymous POST rejects SSE
+    });
+
+    final response = await g4fHttp.send(req).timeout(const Duration(seconds: 30));
+    if (response.statusCode != 200) {
+      final err = await response.stream.bytesToString().timeout(const Duration(seconds: 4));
+      throw Exception('Pollinations POST ${response.statusCode}: $err');
+    }
+    final body = utf8.decode(await response.stream.toBytes().timeout(const Duration(seconds: 30)));
+    if (looksLikeGarbage(body)) {
+      throw Exception('Pollinations POST garbage');
+    }
+    final text = extractOpenAiMessage(body) ?? body.trim();
+    if (!looksLikeModelOutput(text)) {
+      throw Exception('Pollinations POST empty');
+    }
+    yield text;
+  }
+
+  Stream<String> _getPrompt(
+    String model,
+    List<Message> messages, {
+    required bool stream,
+  }) async* {
+    final seed = DateTime.now().millisecondsSinceEpoch % 100000;
+    final prompt = formatPrompt(messages);
+    final url = Uri.parse(
+      '$_getBase/${Uri.encodeComponent(prompt)}?model=$model&seed=$seed',
+    );
+
+    final req = http.Request('GET', url);
+    req.headers.addAll(browserHeaders());
+    final response = await g4fHttp.send(req).timeout(const Duration(seconds: 30));
+    if (response.statusCode != 200) {
+      throw Exception('Pollinations returned status ${response.statusCode}');
+    }
+    final fullText = utf8
+        .decode(await response.stream.toBytes().timeout(const Duration(seconds: 30)))
+        .trim();
+    if (!looksLikeModelOutput(fullText)) {
+      throw Exception('Pollinations GET empty');
+    }
+    yield fullText;
+  }
+}