module.exports = {
  main: async (event) => {
    let { data = {}, userInfo } = event;

    const COZE_TOKEN = 'sat_OiXlI4Da5Q99fxmul6pNfExmA6hR898UbxBDwrvjZ638APxRSlFnXbz6zyFedKNG';
    // 从前端传入 bot_id，不同项目用不同智能体
    const BOT_ID = data.bot_id || '7680345813062680618';

    const res = await uniCloud.httpclient.request('https://api.coze.cn/v3/chat', {
      method: 'POST',
      dataType: 'text',
      contentType: 'json',
      timeout: 120000,
      headers: { 'Authorization': 'Bearer ' + COZE_TOKEN },
      data: {
        bot_id: BOT_ID,
        user_id: (userInfo && userInfo.uid) || 'anonymous',
        stream: true,
        auto_save_history: true,
        additional_messages: [{
          role: 'user',
          content: data.message,
          content_type: 'text'
        }]
      }
    });

    // 扣子 v3 流式事件说明：
    //   conversation.message.delta      —— 增量片段（应当拼接）
    //   conversation.message.completed  —— 该条消息的「完整内容」（不能再次拼接，否则重复）
    // 因此必须按事件类型区分，只累加 delta；completed 仅用于兜底。
    let conversationId = '';
    const msgMap = new Map(); // messageId -> { text }
    let curEvent = '';
    const text = res.data || '';
    const lines = text.split('\n');
    for (const line of lines) {
      if (line.startsWith('event:')) {
        curEvent = line.slice(6).trim();
        continue;
      }
      if (!line.startsWith('data:')) continue;
      const d = line.slice(5).trim();
      if (d === '[DONE]' || d === '"[DONE]"') continue;
      try {
        const p = JSON.parse(d);
        if (p.conversation_id) conversationId = p.conversation_id;
        // 只取正文，忽略 verbose（工具调用日志）等其他类型
        if (p.type !== 'answer' || typeof p.content !== 'string') continue;
        const key = p.id || '__default__';
        const rec = msgMap.get(key) || { text: '' };

        if (curEvent === 'conversation.message.delta') {
          // 防御：万一上游发的是累计内容而非增量，用长度+前缀判断避免重复
          if (p.content.length > rec.text.length && p.content.indexOf(rec.text) === 0) {
            rec.text = p.content;
          } else {
            rec.text += p.content;
          }
          msgMap.set(key, rec);
        } else if (curEvent === 'conversation.message.completed') {
          // 已有 delta 拼出的内容就丢掉 completed，避免重复；没有则用它兜底
          if (!rec.text && p.content) {
            rec.text = p.content;
            msgMap.set(key, rec);
          }
        }
      } catch (e) { /* 跳过 */ }
    }

    // 按消息首次出现顺序拼接（多段消息之间自带换行，直接相连）
    let answer = '';
    for (const rec of msgMap.values()) answer += rec.text;
    if (!answer) answer = '暂时无法回复，请拨打 400-686-5559 咨询';

    return {
      code: 0,
      msg: 'ok',
      data: { answer, conversation_id: conversationId }
    };
  }
};