test001/lib/doubao/DouBao.dart

import 'dart:convert';
import 'package:http/http.dart' as http;

// 假设这是一个包含聊天方法的类
class Doubao {
  final String apiKey;
  final String modelId;
  Doubao({required this.apiKey, required this.modelId});

  Stream<String> chat(String userMessage) async* {
    final client = http.Client();
    final url =
        Uri.parse('https://ark.cn-beijing.volces.com/api/v3/chat/completions');

    final headers = {
      'Content-Type': 'application/json',
      'Authorization': 'Bearer $apiKey',
    };

    final requestBody = {
      "model": modelId,
      "messages": [
        {"role": "system", "content": "你是豆包，是由字节跳动开发的 AI 人工智能助手."},
        {"role": "user", "content": userMessage}
      ],
      "stream": true,
    };

    try {
      final request = http.Request('POST', url)
        ..headers.addAll(headers)
        ..body = jsonEncode(requestBody);

      final response = await client.send(request);
      //流式处理响应数据
      await for (final chunk in response.stream
          .transform(utf8.decoder)
          .transform(const LineSplitter())) {
        if (chunk.isEmpty) continue;

        // 假设豆包API使用类似OpenAI的流式格式（data: {...}）
        if (chunk.startsWith('data:')) {
          final jsonStr = chunk.substring(5).trim();
          if (jsonStr == '[DONE]') break; // 流结束标志

          try {
            final data = jsonDecode(jsonStr);
            final content = data['choices'][0]['delta']['content'] ?? '';
            if (content.isNotEmpty) {
              yield content; // 逐块返回生成的文本
            }
          } catch (e) {
            print('JSON解析错误: $e');
          }
          print('请求成功: $jsonStr');
        }
      }
    } catch (e) {
      print('请求异常: $e');
    }
  }
}