import EscortAgent from "./agent.js";

class ChatTask {
  constructor(options = {}) {
    this.options = {
      modelProvider: options.modelProvider || "deepseek",
      apiKey: options.apiKey,
      baseURL: options.baseURL,
      modelName: options.modelName,
      temperature: options.temperature ?? 0.7,
      maxIterations: options.maxIterations || 10,
    };

    this.agents = new Map();
    this.maxAgents = options.maxAgents || 100;
  }

  async streamChat(userInfo, message, callback) {
    const userId = userInfo ? userInfo._id : message.appId;

    let agent = this.agents.get(userId);
    if (agent) {
      // LRU：重新插入以更新使用顺序
      this.agents.delete(userId);
    } else {
      agent = new EscortAgent();
    }
    this.agents.set(userId, agent);

    // 超出上限时淘汰最久未使用的 Agent，避免内存泄漏
    if (this.agents.size > this.maxAgents) {
      const oldest = this.agents.keys().next().value;
      this.agents.delete(oldest);
    }

    return agent.streamChat(userInfo, [message], callback);
  }
}

const chatTask = new ChatTask();

export { ChatTask, chatTask };
export default chatTask;