package assignment1;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;

public class UserLogin {
    static final String DBURL = "jdbc:mysql://localhost:3306/xiaoshou?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT";

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Connection conn = null;
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        try {
            Class.forName("com.mysql.cj.jdbc.Driver");
            conn = DriverManager.getConnection(DBURL);
            int attempts = 0;
            boolean loginSuccess = false;
            while (attempts < 3 && !loginSuccess) {
                System.out.println("欢迎使用阳光超市收银系统，请登陆");
                System.out.print("请输入用户名: ");
                String username = scanner.nextLine();
                System.out.print("请输入密码: ");
                String password = scanner.nextLine();
                String sql = "SELECT xingming FROM t_yong WHERE yonghuming=? AND mima=?";
                pstmt = conn.prepareStatement(sql);
                pstmt.setString(1, username);
                pstmt.setString(2, Encrypt.MD5(password));
                rs = pstmt.executeQuery();
                if (rs.next()) {
                    loginSuccess = true;
                    String xingming = rs.getString("xingming");
                    SimpleDateFormat formatter = new SimpleDateFormat("yyyy年MM月dd日HH时mm分ss秒");
                    String currentTime = formatter.format(new Date());
                    System.out.println("欢迎使用阳光超市收银系统");
                    System.out.println("当前收银员：" + xingming);
                    System.out.println("当前时间：" + currentTime);
                } else {
                    System.out.println("用户名或密码不正确，请重新输入");
                    attempts++;
                }
            }
            if (!loginSuccess)
                System.out.println("最多只能尝试3次");
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                if (rs != null)
                    rs.close();
                if (pstmt != null)
                    pstmt.close();
                if (conn != null)
                    conn.close();
            } catch (SQLException se) {
                se.printStackTrace();
            }
        }
    }
}