content: /*
   * Copyright (C) 2017 Anthony C. Restaino
   * <p/>
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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
   * <p/>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p/>
   * 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.anthonycr.grant;
  
  import android.content.pm.PackageManager;
  import android.os.Handler;
  import android.os.Looper;
  import android.support.annotation.CallSuper;
  import android.support.annotation.NonNull;
  import android.util.Log;
  
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.Set;
  
  /**
   * This abstract class should be used to create an if/else action that the PermissionsManager
   * can execute when the permissions you request are granted or denied. Simple use involves
   * creating an anonymous instance of it and passing that instance to the
   * requestPermissionsIfNecessaryForResult method. The result will be sent back to you as
   * either onGranted (all permissions have been granted), or onDenied (a required permission
   * has been denied). Ideally you put your functionality in the onGranted method and notify
   * the user what won't work in the onDenied method.
   */
  public abstract class PermissionsResultAction {
  
      private static final String TAG = PermissionsResultAction.class.getSimpleName();
      private final Set<String> mPermissions = new HashSet<>(1);
      private Looper mLooper = Looper.getMainLooper();
  
      /**
       * Default Constructor
       */
      public PermissionsResultAction() {}
  
      /**
       * Alternate Constructor. Pass the looper you wish the PermissionsResultAction
       * callbacks to be executed on if it is not the current Looper. For instance,
       * if you are making a permissions request from a background thread but wish the
       * callback to be on the UI thread, use this constructor to specify the UI Looper.
       *
       * @param looper the looper that the callbacks will be called using.
       */
      @SuppressWarnings("unused")
      public PermissionsResultAction(@NonNull Looper looper) {mLooper = looper;}
  
      /**
       * This method is called when ALL permissions that have been
       * requested have been granted by the user. In this method
       * you should put all your permissions sensitive code that can
       * only be executed with the required permissions.
       */
      public abstract void onGranted();
  
      /**
       * This method is called when a permission has been denied by
       * the user. It provides you with the permission that was denied
       * and will be executed on the Looper you pass to the constructor
       * of this class, or the Looper that this object was created on.
       *
       * @param permission the permission that was denied.
       */
      public abstract void onDenied(String permission);
  
      /**
       * This method is used to determine if a permission not
       * being present on the current Android platform should
       * affect whether the PermissionsResultAction should continue
       * listening for events. By default, it returns true and will
       * simply ignore the permission that did not exist. Usually this will
       * work fine since most new permissions are introduced to
       * restrict what was previously allowed without permission.
       * If that is not the case for your particular permission you
       * request, override this method and return false to result in the
       * Action being denied.
       *
       * @param permission the permission that doesn't exist on this
       *                   Android version
       * @return return true if the PermissionsResultAction should
       * ignore the lack of the permission and proceed with exection
       * or false if the PermissionsResultAction should treat the
       * absence of the permission on the API level as a denial.
       */
      @SuppressWarnings({"WeakerAccess", "SameReturnValue"})
      public synchronized boolean shouldIgnorePermissionNotFound(String permission) {
          Log.d(TAG, "Permission not found: " + permission);
          return true;
      }
  
      @SuppressWarnings("WeakerAccess")
      @CallSuper
      protected synchronized final boolean onResult(final @NonNull String permission, int result) {
          if (result == PackageManager.PERMISSION_GRANTED) {
              return onResult(permission, Permissions.GRANTED);
          } else {
              return onResult(permission, Permissions.DENIED);
          }
  
      }
  
      /**
       * This method is called when a particular permission has changed.
       * This method will be called for all permissions, so this method determines
       * if the permission affects the state or not and whether it can proceed with
       * calling onGranted or if onDenied should be called.
       *
       * @param permission the permission that changed.
       * @param result     the result for that permission.
       * @return this method returns true if its primary action has been completed
       * and it should be removed from the data structure holding a reference to it.
       */
      @SuppressWarnings("WeakerAccess")
      @CallSuper
      protected synchronized final boolean onResult(final @NonNull String permission, Permissions result) {
          mPermissions.remove(permission);
          if (result == Permissions.GRANTED) {
              if (mPermissions.isEmpty()) {
                  new Handler(mLooper).post(new Runnable() {
                      @Override
                      public void run() {
                          onGranted();
                      }
                  });
                  return true;
              }
          } else if (result == Permissions.DENIED) {
              new Handler(mLooper).post(new Runnable() {
                  @Override
                  public void run() {
                      onDenied(permission);
                  }
              });
              return true;
          } else if (result == Permissions.NOT_FOUND) {
              if (shouldIgnorePermissionNotFound(permission)) {
                  if (mPermissions.isEmpty()) {
                      new Handler(mLooper).post(new Runnable() {
                          @Override
                          public void run() {
                              onGranted();
                          }
                      });
                      return true;
                  }
              } else {
                  new Handler(mLooper).post(new Runnable() {
                      @Override
                      public void run() {
                          onDenied(permission);
                      }
                  });
                  return true;
              }
          }
          return false;
      }
  
      /**
       * This method registers the PermissionsResultAction object for the specified permissions
       * so that it will know which permissions to look for changes to. The PermissionsResultAction
       * will then know to look out for changes to these permissions.
       *
       * @param perms the permissions to listen for
       */
      @SuppressWarnings("WeakerAccess")
      @CallSuper
      protected synchronized final void registerPermissions(@NonNull String[] perms) {
          Collections.addAll(mPermissions, perms);
      }
  }
  