帮我把下面的代码抽取出公共部分并且把网络请求抽取到api_service部分使用Dio插件获取验证码图片并返回图片 static FutureWidget getVerifyCodecontext setState async print_pureyzmtoString; if !_pureyzm Dio dio = Dio; print下载了; R

//api_service.dart class ApiService { static Dio dio = Dio();

static Future getVerifyCode() async { Response response = await dio.get( "https://nepuback-nepu-restart-xbbhhovrls.cn-beijing.fcapp.run/jwc_login", options: Options(responseType: ResponseType.bytes)); return response; }

static Future noPerceptionLogin() async { Response response = await dio.get( "https://nepuback-nepu-restart-xbbhhovrls.cn-beijing.fcapp.run/jwc_login", options: Options(responseType: ResponseType.bytes));

for (var item in response.headers
    .value('Set-Cookie')
    .toString()
    .replaceAll('{', '')
    .replaceAll('}', '')
    .replaceAll("'", '')
    .replaceAll(' ', '')
    .split(',')) {
  if (item.length < 50 && item.length > 10) {
    jwc_jsessionid = item;
  }
  if (item.length > 100) {
    jwc_webvpn_key = item;
  }
  if (item.length > 50 && item.length < 100) {
    jwc_webvpn_username = item;
  }
  if (item.length == 4) {
    jwc_verifycode = item;
  }
  if (item.length == 5) {
    await noPerceptionLogin();
  }
}

Response response1 = await dio.get(
    "https://nepu-node-login-nepu-restart-togqejjknk.cn-beijing.fcapp.run/course",
    options: Options(),
    queryParameters: {
      'account': Global.jwc_xuehao,
      'password': Global.jwc_password,
      'verifycode': Global.jwc_verifycode,
      'JSESSIONID': Global.jwc_jsessionid,
      '_webvpn_key': Global.jwc_webvpn_key,
      'webvpn_username': Global.jwc_webvpn_username
    });

return response1;

} }

//原始代码中的部分 static Future getVerifyCode(context, setState) async { if (!_pureyzm) { Response response = await ApiService.getVerifyCode(); for (var item in response.headers .value('Set-Cookie') .toString() .replaceAll('{', '') .replaceAll('}', '') .replaceAll("'", '') .replaceAll(' ', '') .split(',')) { if (item.length < 50 && item.length > 10) { jwc_jsessionid = item; } if (item.length > 100) { jwc_webvpn_key = item; } if (item.length > 50 && item.length < 100) { jwc_webvpn_username = item; } if (item.length == 4) { jwc_verifycode = item; jwc_verifycodeController.text = item; } if (item.length == 5) { setState(() {}); } }

try {
  await AchievementView(context,
      title: "你可以无需验证码登录啦，验证码是",
      subTitle: Global.jwc_verifycode,
      icon: Icon(
        Icons.error,
        color: Colors.white,
      ),
      color: Colors.green,
      duration: Duration(seconds: 3),
      isCircle: true,
      listener: (status) {})
    ..show();
} catch (e) {
  print(e);
}
return Image.memory(response.data);

} else { return Image.asset('assets/jwc_login.jpg'); } }

Future No_perception_login() async { Response response = await ApiService.getVerifyCode();

for (var item in response.headers .value('Set-Cookie') .toString() .replaceAll('{', '') .replaceAll('}', '') .replaceAll("'", '') .replaceAll(' ', '') .split(',')) { if (item.length < 50 && item.length > 10) { jwc_jsessionid = item; } if (item.length > 100) { jwc_webvpn_key = item; } if (item.length > 50 && item.length < 100) { jwc_webvpn_username = item; } if (item.length == 4) { jwc_verifycode = item; } if (item.length == 5) { await ApiService.noPerceptionLogin(); } }