content: /*
   * Copyright (C) 2010 ZXing authors
   *
   * 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.xys.libzxing.zxing.utils;
  
  import android.annotation.SuppressLint;
  import android.app.Activity;
  import android.content.BroadcastReceiver;
  import android.content.Context;
  import android.content.Intent;
  import android.content.IntentFilter;
  import android.os.AsyncTask;
  import android.os.BatteryManager;
  import android.os.Build;
  import android.util.Log;
  
  /**
   * Finishes an activity after a period of inactivity if the device is on battery
   * power.
   */
  public class InactivityTimer {
  
      private static final String TAG = InactivityTimer.class.getSimpleName();
  
      private static final long INACTIVITY_DELAY_MS = 5 * 60 * 1000L;
  
      private Activity activity;
      private BroadcastReceiver powerStatusReceiver;
      private boolean registered;
      private AsyncTask<Object, Object, Object> inactivityTask;
  
      public InactivityTimer(Activity activity) {
          this.activity = activity;
          powerStatusReceiver = new PowerStatusReceiver();
          registered = false;
          onActivity();
      }
  
      @SuppressLint("NewApi")
      public synchronized void onActivity() {
          cancel();
          inactivityTask = new InactivityAsyncTask();
          if (Build.VERSION.SDK_INT >= 11) {
              inactivityTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
          } else {
              inactivityTask.execute();
          }
      }
  
      public synchronized void onPause() {
          cancel();
          if (registered) {
              activity.unregisterReceiver(powerStatusReceiver);
              registered = false;
          } else {
              Log.w(TAG, "PowerStatusReceiver was never registered?");
          }
      }
  
      public synchronized void onResume() {
          if (registered) {
              Log.w(TAG, "PowerStatusReceiver was already registered?");
          } else {
              activity.registerReceiver(powerStatusReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
              registered = true;
          }
          onActivity();
      }
  
      private synchronized void cancel() {
          AsyncTask<?, ?, ?> task = inactivityTask;
          if (task != null) {
              task.cancel(true);
              inactivityTask = null;
          }
      }
  
      public void shutdown() {
          cancel();
      }
  
      private class PowerStatusReceiver extends BroadcastReceiver {
          @Override
          public void onReceive(Context context, Intent intent) {
              if (Intent.ACTION_BATTERY_CHANGED.equals(intent.getAction())) {
                  // 0 indicates that we're on battery
                  boolean onBatteryNow = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, -1) <= 0;
                  if (onBatteryNow) {
                      InactivityTimer.this.onActivity();
                  } else {
                      InactivityTimer.this.cancel();
                  }
              }
          }
      }
  
      private class InactivityAsyncTask extends AsyncTask<Object, Object, Object> {
          @Override
          protected Object doInBackground(Object... objects) {
              try {
                  Thread.sleep(INACTIVITY_DELAY_MS);
                  Log.i(TAG, "Finishing activity due to inactivity");
                  activity.finish();
              } catch (InterruptedException e) {
                  // continue without killing
              }
              return null;
          }
      }
  
  }
  