bw-expo-app/lib/auth/token-manager.ts

import { storage } from '@/lib/storage';

const SESSION_TOKEN_KEY = 'bestaibest.better-auth.session_token';
const TOKEN_REFRESH_THRESHOLD = 5 * 60 * 1000; // 5分钟

interface TokenInfo {
  token: string;
  expiresAt: number;
  refreshToken?: string;
}

/**
 * Token管理器
 * 负责处理token的存储、刷新和生命周期管理
 */
class TokenManager {
  private refreshTimer: NodeJS.Timeout | null = null;

  /**
   * 设置token信息
   */
  async setToken(token: string, expiresIn?: number, refreshToken?: string): Promise<void> {
    const now = Date.now();
    const expiresAt = expiresIn ? now + expiresIn * 1000 : now + 24 * 60 * 60 * 1000; // 默认24小时

    const tokenInfo: TokenInfo = {
      token,
      expiresAt,
      refreshToken,
    };

    await storage.setItem(SESSION_TOKEN_KEY, JSON.stringify(tokenInfo));
    this.scheduleTokenRefresh(expiresAt);
  }

  /**
   * 获取token信息
   */
  async getToken(): Promise<TokenInfo | null> {
    const tokenData = await storage.getItem(SESSION_TOKEN_KEY);
    if (!tokenData) {
      return null;
    }

    try {
      const tokenInfo: TokenInfo = JSON.parse(tokenData);

      // 检查token是否即将过期
      if (this.isTokenExpiring(tokenInfo.expiresAt)) {
        console.log('Token即将过期，尝试刷新...');
        try {
          await this.refreshToken(tokenInfo.refreshToken);
          return this.getToken(); // 递归获取新的token
        } catch (error) {
          console.error('Token刷新失败:', error);
          await this.clearToken();
          return null;
        }
      }

      return tokenInfo;
    } catch (error) {
      console.error('解析token失败:', error);
      await this.clearToken();
      return null;
    }
  }

  /**
   * 获取原始token字符串
   */
  async getTokenString(): Promise<string | null> {
    const tokenInfo = await this.getToken();
    return tokenInfo?.token ?? null;
  }

  /**
   * 检查token是否即将过期
   */
  private isTokenExpiring(expiresAt: number): boolean {
    const now = Date.now();
    return expiresAt - now < TOKEN_REFRESH_THRESHOLD;
  }

  /**
   * 安排token刷新
   */
  private scheduleTokenRefresh(expiresAt: number): void {
    if (this.refreshTimer) {
      clearTimeout(this.refreshTimer);
    }

    const now = Date.now();
    const refreshTime = expiresAt - TOKEN_REFRESH_THRESHOLD - now;

    if (refreshTime > 0) {
      this.refreshTimer = setTimeout(async () => {
        console.log('自动刷新token...');
        try {
          await this.refreshToken();
        } catch (error) {
          console.error('自动刷新token失败:', error);
        }
      }, refreshTime);
    }
  }

  /**
   * 刷新token
   */
  private async refreshToken(refreshToken?: string): Promise<void> {
    // TODO: 实现实际的token刷新逻辑
    // 这里应该调用认证服务的refresh端点

    console.log('执行token刷新...');

    try {
      // 示例刷新逻辑
      // const response = await fetch('/api/auth/refresh', {
      //   method: 'POST',
      //   headers: {
      //     'Content-Type': 'application/json',
      //   },
      //   body: JSON.stringify({
      //     refreshToken: refreshToken || await storage.getItem('refresh_token'),
      //   }),
      // });

      // if (!response.ok) {
      //   throw new Error('刷新失败');
      // }

      // const data = await response.json();
      // await this.setToken(data.accessToken, data.expiresIn, data.refreshToken);

      // 临时实现：清除token，强制重新登录
      throw new Error('Refresh token not implemented');
    } catch (error) {
      console.error('Token刷新失败:', error);
      await this.clearToken();
      throw error;
    }
  }

  /**
   * 清除token
   */
  async clearToken(): Promise<void> {
    if (this.refreshTimer) {
      clearTimeout(this.refreshTimer);
      this.refreshTimer = null;
    }

    await storage.removeItem(SESSION_TOKEN_KEY);
    console.log('Token已清除');
  }

  /**
   * 检查token是否有效
   */
  async isTokenValid(): Promise<boolean> {
    const tokenInfo = await this.getToken();
    if (!tokenInfo) {
      return false;
    }

    const now = Date.now();
    return tokenInfo.expiresAt > now;
  }

  /**
   * 获取token剩余有效时间（毫秒）
   */
  async getTokenRemainingTime(): Promise<number> {
    const tokenInfo = await this.getToken();
    if (!tokenInfo) {
      return 0;
    }

    const now = Date.now();
    return Math.max(0, tokenInfo.expiresAt - now);
  }
}

/**
 * 单例实例
 */
export const tokenManager = new TokenManager();

/**
 * 便捷函数：获取认证头
 */
export async function getAuthHeaders(): Promise<Record<string, string>> {
  const token = await tokenManager.getTokenString();
  return token ? { Authorization: `Bearer ${token}` } : {};
}

/**
 * 便捷函数：检查是否已认证
 */
export async function isAuthenticated(): Promise<boolean> {
  return tokenManager.isTokenValid();
}