package com.ybw.mathapp.util;

import com.ybw.mathapp.entity.User;
import java.io.*;
import java.util.ArrayList;
import java.util.List;

public class LoginFileUtils {
  private static final String USER_FILE = "users.txt";

  // 读取所有用户
  // FileUtils.java 中的 readUsers 方法（简化版）
  public static List<User> readUsers() {
    List<User> users = new ArrayList<>();
    File file = new File(USER_FILE);

    if (!file.exists()) {
      try {
        file.createNewFile();
      } catch (IOException e) {
        System.err.println("创建用户文件失败: " + e.getMessage());
      }
      return users;
    }

    try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
      String line;
      while ((line = reader.readLine()) != null) {
        line = line.trim();
        if (line.isEmpty()) continue;

        User user = User.fromString(line);
        if (user != null) {
          users.add(user);
        }
      }
    } catch (IOException e) {
      System.err.println("读取用户文件失败: " + e.getMessage());
    }
    return users;
  }

  // 保存用户到文件
  public static void saveUser(User user) {
    try (PrintWriter writer = new PrintWriter(new FileWriter(USER_FILE, true))) {
      writer.println(user.toString());
    } catch (IOException e) {
      System.err.println("保存用户信息失败: " + e.getMessage());
    }
  }

  // 检查邮箱是否已注册
  public static boolean isEmailRegistered(String email) {
    List<User> users = readUsers();
    for (User user : users) {
      if (user.getEmail().equalsIgnoreCase(email)) {
        return true;
      }
    }
    return false;
  }

  // 验证用户登录
  public static boolean validateUser(String email, String password) {
    List<User> users = readUsers();
    for (User user : users) {
      if (user.getEmail().equalsIgnoreCase(email) &&
          user.getPassword().equals(password)) {
        return true;
      }
    }
    return false;
  }
}