import 'package:flutter/material.dart';
import 'package:otp/otp.dart';

class UserServeGooglePage extends StatefulWidget {
  const UserServeGooglePage({Key? key}) : super(key: key);

  @override
  State<UserServeGooglePage> createState() => _UserServeGooglePageState();
}

class _UserServeGooglePageState extends State<UserServeGooglePage> {
  String code = '000000';
  String secret = 'T4UM3VPYXPALF7M5';
  int remaining = 0;

  @override
  void initState() {
    super.initState();
    getCode();
  }

  void getCode() {
    setState(() {
      remaining = OTP.remainingSeconds();

      code = OTP.generateTOTPCodeString(
        secret,
        DateTime.now().millisecondsSinceEpoch,
        algorithm: Algorithm.SHA1,
        isGoogle: true,
      );
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('谷歌验证器'),
      ),
      body: Column(
        children: [
          Text(
            code,
            style: const TextStyle(
              fontSize: 32,
            ),
          ),
          Text(remaining.toString()),
          ElevatedButton(
            onPressed: () {
              getCode();
            },
            child: const Text('刷新密码'),
          ),
        ],
      ),
    );
  }
}