content: /*************************** The CRY.ME project (2023) *************************************************
   *
   *  This file is part of the CRY.ME project (https://github.com/ANSSI-FR/cry-me).
   *  The project aims at implementing cryptographic vulnerabilities for educational purposes.
   *  Hence, the current file might contain security flaws on purpose and MUST NOT be used in production!
   *  Please do not use this source code outside this scope, or use it knowingly.
   *
   *  Many files come from the Android element (https://github.com/vector-im/element-android), the
   *  Matrix SDK (https://github.com/matrix-org/matrix-android-sdk2) as well as the Android Yubikit
   *  (https://github.com/Yubico/yubikit-android) projects and have been willingly modified
   *  for the CRY.ME project purposes. The Android element, Matrix SDK and Yubikit projects are distributed
   *  under the Apache-2.0 license, and so is the CRY.ME project.
   *
   ***************************  (END OF CRY.ME HEADER)   *************************************************/
  
  /*
   * Copyright (C) 2020 Yubico.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *       http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.yubico.yubikit.android.ui;
  
  import android.app.Activity;
  import android.content.Intent;
  import android.os.Bundle;
  import android.view.KeyEvent;
  
  import com.yubico.yubikit.android.R;
  import com.yubico.yubikit.android.transport.nfc.NfcYubiKeyDevice;
  import com.yubico.yubikit.android.transport.usb.UsbConfiguration;
  import com.yubico.yubikit.core.YubiKeyDevice;
  import com.yubico.yubikit.core.application.CommandState;
  import com.yubico.yubikit.core.util.Callback;
  import com.yubico.yubikit.core.util.NdefUtils;
  import com.yubico.yubikit.core.util.Pair;
  
  import java.io.IOException;
  
  import javax.annotation.Nullable;
  
  /**
   * An Activity to prompt the user for a YubiKey to retrieve an OTP from a YubiOTP slot.
   */
  public class OtpActivity extends YubiKeyPromptActivity {
      public static final int RESULT_ERROR = RESULT_FIRST_USER;
  
      public static final String EXTRA_OTP = "otp";
      public static final String EXTRA_ERROR = "error";
  
      private OtpKeyListener keyListener;
  
      private int usbSessionCounter = 0;
  
      @Override
      protected void onCreate(@Nullable Bundle savedInstanceState) {
          getIntent().putExtra(ARG_ACTION_CLASS, YubiKeyNdefAction.class);
          getIntent().putExtra(ARG_ALLOW_USB, false);  // Custom USB handling for keyboard.
  
          super.onCreate(savedInstanceState);
  
          getYubiKitManager().startUsbDiscovery(new UsbConfiguration().handlePermissions(false), device -> {
              usbSessionCounter++;
              device.setOnClosed(() -> {
                  usbSessionCounter--;
                  if (usbSessionCounter == 0) {
                      runOnUiThread(() -> helpTextView.setText(isNfcEnabled() ? R.string.yubikit_prompt_plug_in_or_tap : R.string.yubikit_prompt_plug_in));
                  }
              });
              runOnUiThread(() -> helpTextView.setText(R.string.yubikit_otp_touch));
          });
  
          keyListener = new OtpKeyListener(new OtpKeyListener.OtpListener() {
              @Override
              public void onCaptureStarted() {
                  helpTextView.setText(R.string.yubikit_prompt_wait);
              }
  
              @Override
              public void onCaptureComplete(String capture) {
                  Intent intent = new Intent();
                  intent.putExtra(EXTRA_OTP, capture);
                  setResult(Activity.RESULT_OK, intent);
                  finish();
              }
          });
      }
  
      @Override
      protected void onDestroy() {
          getYubiKitManager().stopUsbDiscovery();
          super.onDestroy();
      }
  
      @Override
      public boolean onKeyUp(int keyCode, KeyEvent event) {
          return keyListener.onKeyEvent(event);
      }
  
      static class YubiKeyNdefAction extends YubiKeyPromptAction {
          @Override
          void onYubiKey(YubiKeyDevice device, Bundle extras, CommandState commandState, Callback<Pair<Integer, Intent>> callback) {
              if (device instanceof NfcYubiKeyDevice) {
                  Intent intent = new Intent();
                  try {
                      String credential = NdefUtils.getNdefPayload(((NfcYubiKeyDevice) device).readNdef());
                      intent.putExtra(EXTRA_OTP, credential);
                      callback.invoke(new Pair<>(RESULT_OK, intent));
                  } catch (IOException e) {
                      intent.putExtra(EXTRA_ERROR, e);
                      callback.invoke(new Pair<>(RESULT_ERROR, intent));
                  }
              }
          }
      }
  }
  