authenticateUser method

Implementation

Future<String?> authenticateUser(AuthInfo authInfo, String scope,
    String deviceCodeUrl, BuildContext context) async {
  try {
    final deviceCodeResponse =
        await getDeviceCode(authInfo.clientId, scope, deviceCodeUrl);
    final userCode = deviceCodeResponse['user_code'];
    final verificationUri = deviceCodeResponse['verification_uri'];

    String fullVerificationUrl = "$verificationUri?code=$userCode";

    print('Please go to $fullVerificationUrl');

    showDialog<void>(
      context: context,
      builder: (BuildContext context) {
        return AlertDialog(
          title: const Text('Login with your phone'),
          content: SizedBox(
            height: 200,
            width: 200,
            child: QrImageView(
              eyeStyle: const QrEyeStyle(
                color: Colors.white,
                eyeShape: QrEyeShape.square,
              ),
              dataModuleStyle: const QrDataModuleStyle(
                color: Colors.white,
                dataModuleShape: QrDataModuleShape.square,
              ),
              data: fullVerificationUrl,
              version: QrVersions.auto,
              // size: 200.0,
            ),
          ),
          actions: <Widget>[
            TextButton(
              style: TextButton.styleFrom(
                textStyle: Theme.of(context).textTheme.labelLarge,
              ),
              child: const Text('Done'),
              onPressed: () {
                Navigator.of(context).pop();
              },
            ),
          ],
        );
      },
    );

    final code = deviceCodeResponse['device_code'];
    final interval = deviceCodeResponse['interval'];
    var token = await pollForToken(
      code,
      interval,
      authInfo.clientId,
      authInfo.tokenUrl,
      scope,
    );

    return token;
  } catch (e) {
    print('Error: $e');
  }

  return null;
}