import 'dart:convert';
import 'package:http/http.dart' as http;
import '../http_client.dart';
import 'package:uuid/uuid.dart';
import '../http_util.dart';
import '../models.dart';
import '../sse.dart';
import 'base_provider.dart';

/// Port of g4f.Provider.Liaobots — guest auth code + chat.
class Liaobots extends BaseProvider {
  @override
  String get name => 'Liaobots';

  @override
  bool get working => true;

  @override
  List<String> get models => ['gpt-3.5-turbo', 'gpt-4'];

  @override
  String get defaultModel => 'gpt-3.5-turbo';

  static const _hosts = [
    'https://liaobots.work',
    'https://liaobots.site',
    'https://liaobots.com',
  ];

  @override
  Stream<String> createAsyncGenerator(
    String model,
    List<Message> messages, {
    bool stream = false,
  }) async* {
    Object? last;
    for (final host in _hosts) {
      try {
        yield await _chat(host, model, messages);
        return;
      } catch (e) {
        last = e;
      }
    }
    throw Exception('Liaobots failed: $last');
  }

  Future<String> _chat(String host, String model, List<Message> messages) async {
    final headers = browserHeaders(
      origin: host,
      referer: '$host/',
      contentType: 'application/json',
    );
    final login = await g4fHttp
        .post(
          Uri.parse('$host/api/user'),
          headers: headers,
          body: jsonEncode({'authcode': const Uuid().v4()}),
        )
        .timeout(const Duration(seconds: 12));
    String? auth;
    if (login.statusCode == 200) {
      try {
        final data = jsonDecode(login.body);
        auth = (data is Map ? (data['authCode'] ?? data['authcode']) : null)
            ?.toString();
      } catch (_) {}
    }

    final req = http.Request('POST', Uri.parse('$host/api/chat'));
    req.headers.addAll({
      ...headers,
      if (auth != null) 'x-auth-code': auth,
      if (auth != null) 'authorization': auth,
    });
    req.body = jsonEncode({
      'conversationId': const Uuid().v4(),
      'model': {
        'id': models.contains(model) ? model : defaultModel,
        'name': model,
        'maxLength': 24000,
        'tokenLimit': 8000,
      },
      'messages': toOpenAiMessages(messages),
      'key': '',
      'prompt': extractSystemMessage(messages),
    });
    final res = await g4fHttp.send(req).timeout(requestTimeout);
    if (res.statusCode != 200) {
      throw Exception('Liaobots ${res.statusCode} @ $host');
    }
    final raw = utf8.decode(await res.stream.toBytes().timeout(requestTimeout));
    final sse = extractAllSseContent(raw).join();
    final text = looksLikeModelOutput(sse) ? sse : raw.trim();
    if (!looksLikeModelOutput(text)) throw Exception('Liaobots empty @ $host');
    return text;
  }
}