content: /*
   * Copyright (C) 2013 The Android Open Source Project
   *
   * 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 android.print;
  
  import android.annotation.NonNull;
  import android.annotation.Nullable;
  import android.annotation.RequiresFeature;
  import android.annotation.RequiresPermission;
  import android.annotation.SystemApi;
  import android.annotation.SystemService;
  import android.annotation.UnsupportedAppUsage;
  import android.app.Activity;
  import android.app.Application.ActivityLifecycleCallbacks;
  import android.content.ComponentName;
  import android.content.Context;
  import android.content.IntentSender;
  import android.content.IntentSender.SendIntentException;
  import android.content.pm.PackageManager;
  import android.graphics.drawable.Icon;
  import android.os.Bundle;
  import android.os.CancellationSignal;
  import android.os.Handler;
  import android.os.ICancellationSignal;
  import android.os.Looper;
  import android.os.Message;
  import android.os.ParcelFileDescriptor;
  import android.os.RemoteException;
  import android.print.PrintDocumentAdapter.LayoutResultCallback;
  import android.print.PrintDocumentAdapter.WriteResultCallback;
  import android.printservice.PrintServiceInfo;
  import android.printservice.recommendation.IRecommendationsChangeListener;
  import android.printservice.recommendation.RecommendationInfo;
  import android.text.TextUtils;
  import android.util.ArrayMap;
  import android.util.Log;
  
  import com.android.internal.os.SomeArgs;
  import com.android.internal.util.Preconditions;
  
  import libcore.io.IoUtils;
  
  import java.lang.ref.WeakReference;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import java.util.Map;
  
  /**
   * System level service for accessing the printing capabilities of the platform.
   *
   * <h3>Print mechanics</h3>
   * <p>
   * The key idea behind printing on the platform is that the content to be printed
   * should be laid out for the currently selected print options resulting in an
   * optimized output and higher user satisfaction. To achieve this goal the platform
   * declares a contract that the printing application has to follow which is defined
   * by the {@link PrintDocumentAdapter} class. At a higher level the contract is that
   * when the user selects some options from the print UI that may affect the way
   * content is laid out, for example page size, the application receives a callback
   * allowing it to layout the content to better fit these new constraints. After a
   * layout pass the system may ask the application to render one or more pages one
   * or more times. For example, an application may produce a single column list for
   * smaller page sizes and a multi-column table for larger page sizes.
   * </p>
   * <h3>Print jobs</h3>
   * <p>
   * Print jobs are started by calling the {@link #print(String, PrintDocumentAdapter,
   * PrintAttributes)} from an activity which results in bringing up the system print
   * UI. Once the print UI is up, when the user changes a selected print option that
   * affects the way content is laid out the system starts to interact with the
   * application following the mechanics described the section above.
   * </p>
   * <p>
   * Print jobs can be in {@link PrintJobInfo#STATE_CREATED created}, {@link
   * PrintJobInfo#STATE_QUEUED queued}, {@link PrintJobInfo#STATE_STARTED started},
   * {@link PrintJobInfo#STATE_BLOCKED blocked}, {@link PrintJobInfo#STATE_COMPLETED
   * completed}, {@link PrintJobInfo#STATE_FAILED failed}, and {@link
   * PrintJobInfo#STATE_CANCELED canceled} state. Print jobs are stored in dedicated
   * system spooler until they are handled which is they are cancelled or completed.
   * Active print jobs, ones that are not cancelled or completed, are considered failed
   * if the device reboots as the new boot may be after a very long time. The user may
   * choose to restart such print jobs. Once a print job is queued all relevant content
   * is stored in the system spooler and its lifecycle becomes detached from this of
   * the application that created it.
   * </p>
   * <p>
   * An applications can query the print spooler for current print jobs it created
   * but not print jobs created by other applications.
   * </p>
   *
   * @see PrintJob
   * @see PrintJobInfo
   */
  @SystemService(Context.PRINT_SERVICE)
  @RequiresFeature(PackageManager.FEATURE_PRINTING)
  public final class PrintManager {
  
      private static final String LOG_TAG = "PrintManager";
  
      private static final boolean DEBUG = false;
  
      private static final int MSG_NOTIFY_PRINT_JOB_STATE_CHANGED = 1;
  
      /**
       * Package name of print spooler.
       *
       * @hide
       */
      public static final String PRINT_SPOOLER_PACKAGE_NAME = "com.android.printspooler";
  
      /**
       * Select enabled services.
       * </p>
       * @see #getPrintServices
       * @hide
       */
      @SystemApi
      public static final int ENABLED_SERVICES = 1 << 0;
  
      /**
       * Select disabled services.
       * </p>
       * @see #getPrintServices
       * @hide
       */
      public static final int DISABLED_SERVICES = 1 << 1;
  
      /**
       * Select all services.
       * </p>
       * @see #getPrintServices
       * @hide
       */
      public static final int ALL_SERVICES = ENABLED_SERVICES | DISABLED_SERVICES;
  
      /**
       * The action for launching the print dialog activity.
       *
       * @hide
       */
      public static final String ACTION_PRINT_DIALOG = "android.print.PRINT_DIALOG";
  
      /**
       * Extra with the intent for starting the print dialog.
       * <p>
       * <strong>Type:</strong> {@link android.content.IntentSender}
       * </p>
       *
       * @hide
       */
      public static final String EXTRA_PRINT_DIALOG_INTENT =
              "android.print.intent.extra.EXTRA_PRINT_DIALOG_INTENT";
  
      /**
       * Extra with a print job.
       * <p>
       * <strong>Type:</strong> {@link android.print.PrintJobInfo}
       * </p>
       *
       * @hide
       */
      public static final String EXTRA_PRINT_JOB =
              "android.print.intent.extra.EXTRA_PRINT_JOB";
  
      /**
       * Extra with the print document adapter to be printed.
       * <p>
       * <strong>Type:</strong> {@link android.print.IPrintDocumentAdapter}
       * </p>
       *
       * @hide
       */
      public static final String EXTRA_PRINT_DOCUMENT_ADAPTER =
              "android.print.intent.extra.EXTRA_PRINT_DOCUMENT_ADAPTER";
  
      /** @hide */
      public static final int APP_ID_ANY = -2;
  
      private final Context mContext;
  
      private final IPrintManager mService;
  
      private final int mUserId;
  
      private final int mAppId;
  
      private final Handler mHandler;
  
      private Map<PrintJobStateChangeListener, PrintJobStateChangeListenerWrapper>
              mPrintJobStateChangeListeners;
      private Map<PrintServicesChangeListener, PrintServicesChangeListenerWrapper>
              mPrintServicesChangeListeners;
      private Map<PrintServiceRecommendationsChangeListener,
              PrintServiceRecommendationsChangeListenerWrapper>
              mPrintServiceRecommendationsChangeListeners;
  
      /** @hide */
      public interface PrintJobStateChangeListener {
  
          /**
           * Callback notifying that a print job state changed.
           *
           * @param printJobId The print job id.
           */
          public void onPrintJobStateChanged(PrintJobId printJobId);
      }
  
      /**
       * Listen for changes to {@link #getPrintServices(int)}.
       *
       * @hide
       */
      @SystemApi
      public interface PrintServicesChangeListener {
  
          /**
           * Callback notifying that the print services changed.
           */
          void onPrintServicesChanged();
      }
  
      /**
       * Listen for changes to {@link #getPrintServiceRecommendations()}.
       *
       * @hide
       */
      @SystemApi
      public interface PrintServiceRecommendationsChangeListener {
  
          /**
           * Callback notifying that the print service recommendations changed.
           */
          void onPrintServiceRecommendationsChanged();
      }
  
      /**
       * Creates a new instance.
       *
       * @param context The current context in which to operate.
       * @param service The backing system service.
       * @param userId The user id in which to operate.
       * @param appId The application id in which to operate.
       * @hide
       */
      public PrintManager(Context context, IPrintManager service, int userId, int appId) {
          mContext = context;
          mService = service;
          mUserId = userId;
          mAppId = appId;
          mHandler = new Handler(context.getMainLooper(), null, false) {
              @Override
              public void handleMessage(Message message) {
                  switch (message.what) {
                      case MSG_NOTIFY_PRINT_JOB_STATE_CHANGED: {
                          SomeArgs args = (SomeArgs) message.obj;
                          PrintJobStateChangeListenerWrapper wrapper =
                                  (PrintJobStateChangeListenerWrapper) args.arg1;
                          PrintJobStateChangeListener listener = wrapper.getListener();
                          if (listener != null) {
                              PrintJobId printJobId = (PrintJobId) args.arg2;
                              listener.onPrintJobStateChanged(printJobId);
                          }
                          args.recycle();
                      } break;
                  }
              }
          };
      }
  
      /**
       * Creates an instance that can access all print jobs.
       *
       * @param userId The user id for which to get all print jobs.
       * @return An instance if the caller has the permission to access all print
       *         jobs, null otherwise.
       * @hide
       */
      public PrintManager getGlobalPrintManagerForUser(int userId) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return null;
          }
          return new PrintManager(mContext, mService, userId, APP_ID_ANY);
      }
  
      PrintJobInfo getPrintJobInfo(PrintJobId printJobId) {
          try {
              return mService.getPrintJobInfo(printJobId, mAppId, mUserId);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      /**
       * Adds a listener for observing the state of print jobs.
       *
       * @param listener The listener to add.
       * @hide
       */
      @UnsupportedAppUsage
      public void addPrintJobStateChangeListener(PrintJobStateChangeListener listener) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          if (mPrintJobStateChangeListeners == null) {
              mPrintJobStateChangeListeners = new ArrayMap<>();
          }
          PrintJobStateChangeListenerWrapper wrappedListener =
                  new PrintJobStateChangeListenerWrapper(listener, mHandler);
          try {
              mService.addPrintJobStateChangeListener(wrappedListener, mAppId, mUserId);
              mPrintJobStateChangeListeners.put(listener, wrappedListener);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      /**
       * Removes a listener for observing the state of print jobs.
       *
       * @param listener The listener to remove.
       * @hide
       */
      public void removePrintJobStateChangeListener(PrintJobStateChangeListener listener) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          if (mPrintJobStateChangeListeners == null) {
              return;
          }
          PrintJobStateChangeListenerWrapper wrappedListener =
                  mPrintJobStateChangeListeners.remove(listener);
          if (wrappedListener == null) {
              return;
          }
          if (mPrintJobStateChangeListeners.isEmpty()) {
              mPrintJobStateChangeListeners = null;
          }
          wrappedListener.destroy();
          try {
              mService.removePrintJobStateChangeListener(wrappedListener, mUserId);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      /**
       * Gets a print job given its id.
       *
       * @param printJobId The id of the print job.
       * @return The print job list.
       * @see PrintJob
       * @hide
       */
      public PrintJob getPrintJob(PrintJobId printJobId) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return null;
          }
          try {
              PrintJobInfo printJob = mService.getPrintJobInfo(printJobId, mAppId, mUserId);
              if (printJob != null) {
                  return new PrintJob(printJob, this);
              }
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
          return null;
      }
  
      /**
       * Get the custom icon for a printer. If the icon is not cached, the icon is
       * requested asynchronously. Once it is available the printer is updated.
       *
       * @param printerId the id of the printer the icon should be loaded for
       * @return the custom icon to be used for the printer or null if the icon is
       *         not yet available
       * @see android.print.PrinterInfo.Builder#setHasCustomPrinterIcon(boolean)
       * @hide
       */
      public Icon getCustomPrinterIcon(PrinterId printerId) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return null;
          }
          try {
              return mService.getCustomPrinterIcon(printerId, mUserId);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      /**
       * Gets the print jobs for this application.
       *
       * @return The print job list.
       * @see PrintJob
       */
      public @NonNull List<PrintJob> getPrintJobs() {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return Collections.emptyList();
          }
          try {
              List<PrintJobInfo> printJobInfos = mService.getPrintJobInfos(mAppId, mUserId);
              if (printJobInfos == null) {
                  return Collections.emptyList();
              }
              final int printJobCount = printJobInfos.size();
              List<PrintJob> printJobs = new ArrayList<PrintJob>(printJobCount);
              for (int i = 0; i < printJobCount; i++) {
                  printJobs.add(new PrintJob(printJobInfos.get(i), this));
              }
              return printJobs;
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      void cancelPrintJob(PrintJobId printJobId) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          try {
              mService.cancelPrintJob(printJobId, mAppId, mUserId);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      void restartPrintJob(PrintJobId printJobId) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          try {
              mService.restartPrintJob(printJobId, mAppId, mUserId);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      /**
       * Creates a print job for printing a {@link PrintDocumentAdapter} with
       * default print attributes.
       * <p>
       * Calling this method brings the print UI allowing the user to customize
       * the print job and returns a {@link PrintJob} object without waiting for the
       * user to customize or confirm the print job. The returned print job instance
       * is in a {@link PrintJobInfo#STATE_CREATED created} state.
       * <p>
       * This method can be called only from an {@link Activity}. The rationale is that
       * printing from a service will create an inconsistent user experience as the print
       * UI would appear without any context.
       * </p>
       * <p>
       * Also the passed in {@link PrintDocumentAdapter} will be considered invalid if
       * your activity is finished. The rationale is that once the activity that
       * initiated printing is finished, the provided adapter may be in an inconsistent
       * state as it may depend on the UI presented by the activity.
       * </p>
       * <p>
       * The default print attributes are a hint to the system how the data is to
       * be printed. For example, a photo editor may look at the photo aspect ratio
       * to determine the default orientation and provide a hint whether the printing
       * should be in portrait or landscape. The system will do a best effort to
       * selected the hinted options in the print dialog, given the current printer
       * supports them.
       * </p>
       * <p>
       * <strong>Note:</strong> Calling this method will bring the print dialog and
       * the system will connect to the provided {@link PrintDocumentAdapter}. If a
       * configuration change occurs that you application does not handle, for example
       * a rotation change, the system will drop the connection to the adapter as the
       * activity has to be recreated and the old adapter may be invalid in this context,
       * hence a new adapter instance is required. As a consequence, if your activity
       * does not handle configuration changes (default behavior), you have to save the
       * state that you were printing and call this method again when your activity
       * is recreated.
       * </p>
       *
       * @param printJobName A name for the new print job which is shown to the user.
       * @param documentAdapter An adapter that emits the document to print.
       * @param attributes The default print job attributes or <code>null</code>.
       * @return The created print job on success or null on failure.
       * @throws IllegalStateException If not called from an {@link Activity}.
       * @throws IllegalArgumentException If the print job name is empty or the
       * document adapter is null.
       *
       * @see PrintJob
       */
      public @NonNull PrintJob print(@NonNull String printJobName,
              @NonNull PrintDocumentAdapter documentAdapter,
              @Nullable PrintAttributes attributes) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return null;
          }
          if (!(mContext instanceof Activity)) {
              throw new IllegalStateException("Can print only from an activity");
          }
          if (TextUtils.isEmpty(printJobName)) {
              throw new IllegalArgumentException("printJobName cannot be empty");
          }
          if (documentAdapter == null) {
              throw new IllegalArgumentException("documentAdapter cannot be null");
          }
          PrintDocumentAdapterDelegate delegate = new PrintDocumentAdapterDelegate(
                  (Activity) mContext, documentAdapter);
          try {
              Bundle result = mService.print(printJobName, delegate,
                      attributes, mContext.getPackageName(), mAppId, mUserId);
              if (result != null) {
                  PrintJobInfo printJob = result.getParcelable(EXTRA_PRINT_JOB);
                  IntentSender intent = result.getParcelable(EXTRA_PRINT_DIALOG_INTENT);
                  if (printJob == null || intent == null) {
                      return null;
                  }
                  try {
                      mContext.startIntentSender(intent, null, 0, 0, 0);
                      return new PrintJob(printJob, this);
                  } catch (SendIntentException sie) {
                      Log.e(LOG_TAG, "Couldn't start print job config activity.", sie);
                  }
              }
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
          return null;
      }
  
      /**
       * Listen for changes to the installed and enabled print services.
       *
       * @param listener the listener to add
       * @param handler the handler the listener is called back on
       *
       * @see android.print.PrintManager#getPrintServices
       *
       * @hide
       */
      @SystemApi
      @RequiresPermission(android.Manifest.permission.READ_PRINT_SERVICES)
      public void addPrintServicesChangeListener(@NonNull PrintServicesChangeListener listener,
              @Nullable Handler handler) {
          Preconditions.checkNotNull(listener);
  
          if (handler == null) {
              handler = mHandler;
          }
  
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          if (mPrintServicesChangeListeners == null) {
              mPrintServicesChangeListeners = new ArrayMap<>();
          }
          PrintServicesChangeListenerWrapper wrappedListener =
                  new PrintServicesChangeListenerWrapper(listener, handler);
          try {
              mService.addPrintServicesChangeListener(wrappedListener, mUserId);
              mPrintServicesChangeListeners.put(listener, wrappedListener);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      /**
       * Stop listening for changes to the installed and enabled print services.
       *
       * @param listener the listener to remove
       *
       * @see android.print.PrintManager#getPrintServices
       *
       * @hide
       */
      @SystemApi
      @RequiresPermission(android.Manifest.permission.READ_PRINT_SERVICES)
      public void removePrintServicesChangeListener(@NonNull PrintServicesChangeListener listener) {
          Preconditions.checkNotNull(listener);
  
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          if (mPrintServicesChangeListeners == null) {
              return;
          }
          PrintServicesChangeListenerWrapper wrappedListener =
                  mPrintServicesChangeListeners.remove(listener);
          if (wrappedListener == null) {
              return;
          }
          if (mPrintServicesChangeListeners.isEmpty()) {
              mPrintServicesChangeListeners = null;
          }
          wrappedListener.destroy();
          try {
              mService.removePrintServicesChangeListener(wrappedListener, mUserId);
          } catch (RemoteException re) {
              Log.e(LOG_TAG, "Error removing print services change listener", re);
          }
      }
  
      /**
       * Gets the list of print services, but does not register for updates. The user has to register
       * for updates by itself, or use {@link PrintServicesLoader}.
       *
       * @param selectionFlags flags selecting which services to get. Either
       *                       {@link #ENABLED_SERVICES},{@link #DISABLED_SERVICES}, or both.
       *
       * @return The print service list or an empty list.
       *
       * @see #addPrintServicesChangeListener(PrintServicesChangeListener, Handler)
       * @see #removePrintServicesChangeListener(PrintServicesChangeListener)
       *
       * @hide
       */
      @SystemApi
      @RequiresPermission(android.Manifest.permission.READ_PRINT_SERVICES)
      public @NonNull List<PrintServiceInfo> getPrintServices(int selectionFlags) {
          Preconditions.checkFlagsArgument(selectionFlags, ALL_SERVICES);
  
          try {
              List<PrintServiceInfo> services = mService.getPrintServices(selectionFlags, mUserId);
              if (services != null) {
                  return services;
              }
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
          return Collections.emptyList();
      }
  
      /**
       * Listen for changes to the print service recommendations.
       *
       * @param listener the listener to add
       * @param handler the handler the listener is called back on
       *
       * @see android.print.PrintManager#getPrintServiceRecommendations
       *
       * @hide
       */
      @SystemApi
      @RequiresPermission(android.Manifest.permission.READ_PRINT_SERVICE_RECOMMENDATIONS)
      public void addPrintServiceRecommendationsChangeListener(
              @NonNull PrintServiceRecommendationsChangeListener listener,
              @Nullable Handler handler) {
          Preconditions.checkNotNull(listener);
  
          if (handler == null) {
              handler = mHandler;
          }
  
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          if (mPrintServiceRecommendationsChangeListeners == null) {
              mPrintServiceRecommendationsChangeListeners = new ArrayMap<>();
          }
          PrintServiceRecommendationsChangeListenerWrapper wrappedListener =
                  new PrintServiceRecommendationsChangeListenerWrapper(listener, handler);
          try {
              mService.addPrintServiceRecommendationsChangeListener(wrappedListener, mUserId);
              mPrintServiceRecommendationsChangeListeners.put(listener, wrappedListener);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      /**
       * Stop listening for changes to the print service recommendations.
       *
       * @param listener the listener to remove
       *
       * @see android.print.PrintManager#getPrintServiceRecommendations
       *
       * @hide
       */
      @SystemApi
      @RequiresPermission(android.Manifest.permission.READ_PRINT_SERVICE_RECOMMENDATIONS)
      public void removePrintServiceRecommendationsChangeListener(
              @NonNull PrintServiceRecommendationsChangeListener listener) {
          Preconditions.checkNotNull(listener);
  
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          if (mPrintServiceRecommendationsChangeListeners == null) {
              return;
          }
          PrintServiceRecommendationsChangeListenerWrapper wrappedListener =
                  mPrintServiceRecommendationsChangeListeners.remove(listener);
          if (wrappedListener == null) {
              return;
          }
          if (mPrintServiceRecommendationsChangeListeners.isEmpty()) {
              mPrintServiceRecommendationsChangeListeners = null;
          }
          wrappedListener.destroy();
          try {
              mService.removePrintServiceRecommendationsChangeListener(wrappedListener, mUserId);
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
      }
  
      /**
       * Gets the list of print service recommendations, but does not register for updates. The user
       * has to register for updates by itself, or use {@link PrintServiceRecommendationsLoader}.
       *
       * @return The print service recommendations list or an empty list.
       *
       * @see #addPrintServiceRecommendationsChangeListener
       * @see #removePrintServiceRecommendationsChangeListener
       *
       * @hide
       */
      @SystemApi
      @RequiresPermission(android.Manifest.permission.READ_PRINT_SERVICE_RECOMMENDATIONS)
      public @NonNull List<RecommendationInfo> getPrintServiceRecommendations() {
          try {
              List<RecommendationInfo> recommendations =
                      mService.getPrintServiceRecommendations(mUserId);
              if (recommendations != null) {
                  return recommendations;
              }
          } catch (RemoteException re) {
              throw re.rethrowFromSystemServer();
          }
          return Collections.emptyList();
      }
  
      /**
       * @hide
       */
      public PrinterDiscoverySession createPrinterDiscoverySession() {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return null;
          }
          return new PrinterDiscoverySession(mService, mContext, mUserId);
      }
  
      /**
       * Enable or disable a print service.
       *
       * @param service The service to enabled or disable
       * @param isEnabled whether the service should be enabled or disabled
       *
       * @hide
       */
      public void setPrintServiceEnabled(@NonNull ComponentName service, boolean isEnabled) {
          if (mService == null) {
              Log.w(LOG_TAG, "Feature android.software.print not available");
              return;
          }
          try {
              mService.setPrintServiceEnabled(service, isEnabled, mUserId);
          } catch (RemoteException re) {
              Log.e(LOG_TAG, "Error enabling or disabling " + service, re);
          }
      }
  
      /**
       * @hide
       */
      public static final class PrintDocumentAdapterDelegate extends IPrintDocumentAdapter.Stub
              implements ActivityLifecycleCallbacks {
          private final Object mLock = new Object();
  
          private Activity mActivity; // Strong reference OK - cleared in destroy
  
          private PrintDocumentAdapter mDocumentAdapter; // Strong reference OK - cleared in destroy
  
          private Handler mHandler; // Strong reference OK - cleared in destroy
  
          private IPrintDocumentAdapterObserver mObserver; // Strong reference OK - cleared in destroy
  
          private DestroyableCallback mPendingCallback;
  
          public PrintDocumentAdapterDelegate(Activity activity,
                  PrintDocumentAdapter documentAdapter) {
              if (activity.isFinishing()) {
                  // The activity is already dead hence the onActivityDestroyed callback won't be
                  // triggered. Hence it is not save to print in this situation.
                  throw new IllegalStateException("Cannot start printing for finishing activity");
              }
  
              mActivity = activity;
              mDocumentAdapter = documentAdapter;
              mHandler = new MyHandler(mActivity.getMainLooper());
              mActivity.getApplication().registerActivityLifecycleCallbacks(this);
          }
  
          @Override
          public void setObserver(IPrintDocumentAdapterObserver observer) {
              final boolean destroyed;
              synchronized (mLock) {
                  mObserver = observer;
                  destroyed = isDestroyedLocked();
              }
  
              if (destroyed && observer != null) {
                  try {
                      observer.onDestroy();
                  } catch (RemoteException re) {
                      Log.e(LOG_TAG, "Error announcing destroyed state", re);
                  }
              }
          }
  
          @Override
          public void start() {
              synchronized (mLock) {
                  // If destroyed the handler is null.
                  if (!isDestroyedLocked()) {
                      mHandler.obtainMessage(MyHandler.MSG_ON_START,
                              mDocumentAdapter).sendToTarget();
                  }
              }
          }
  
          @Override
          public void layout(PrintAttributes oldAttributes, PrintAttributes newAttributes,
                  ILayoutResultCallback callback, Bundle metadata, int sequence) {
  
              ICancellationSignal cancellationTransport = CancellationSignal.createTransport();
              try {
                  callback.onLayoutStarted(cancellationTransport, sequence);
              } catch (RemoteException re) {
                  // The spooler is dead - can't recover.
                  Log.e(LOG_TAG, "Error notifying for layout start", re);
                  return;
              }
  
              synchronized (mLock) {
                  // If destroyed the handler is null.
                  if (isDestroyedLocked()) {
                      return;
                  }
  
                  CancellationSignal cancellationSignal = CancellationSignal.fromTransport(
                          cancellationTransport);
  
                  SomeArgs args = SomeArgs.obtain();
                  args.arg1 = mDocumentAdapter;
                  args.arg2 = oldAttributes;
                  args.arg3 = newAttributes;
                  args.arg4 = cancellationSignal;
                  args.arg5 = new MyLayoutResultCallback(callback, sequence);
                  args.arg6 = metadata;
  
                  mHandler.obtainMessage(MyHandler.MSG_ON_LAYOUT, args).sendToTarget();
              }
          }
  
          @Override
          public void write(PageRange[] pages, ParcelFileDescriptor fd,
                  IWriteResultCallback callback, int sequence) {
  
              ICancellationSignal cancellationTransport = CancellationSignal.createTransport();
              try {
                  callback.onWriteStarted(cancellationTransport, sequence);
              } catch (RemoteException re) {
                  // The spooler is dead - can't recover.
                  Log.e(LOG_TAG, "Error notifying for write start", re);
                  return;
              }
  
              synchronized (mLock) {
                  // If destroyed the handler is null.
                  if (isDestroyedLocked()) {
                      return;
                  }
  
                  CancellationSignal cancellationSignal = CancellationSignal.fromTransport(
                          cancellationTransport);
  
                  SomeArgs args = SomeArgs.obtain();
                  args.arg1 = mDocumentAdapter;
                  args.arg2 = pages;
                  args.arg3 = fd;
                  args.arg4 = cancellationSignal;
                  args.arg5 = new MyWriteResultCallback(callback, fd, sequence);
  
                  mHandler.obtainMessage(MyHandler.MSG_ON_WRITE, args).sendToTarget();
              }
          }
  
          @Override
          public void finish() {
              synchronized (mLock) {
                  // If destroyed the handler is null.
                  if (!isDestroyedLocked()) {
                      mHandler.obtainMessage(MyHandler.MSG_ON_FINISH,
                              mDocumentAdapter).sendToTarget();
                  }
              }
          }
  
          @Override
          public void kill(String reason) {
              synchronized (mLock) {
                  // If destroyed the handler is null.
                  if (!isDestroyedLocked()) {
                      mHandler.obtainMessage(MyHandler.MSG_ON_KILL,
                              reason).sendToTarget();
                  }
              }
          }
  
          @Override
          public void onActivityPaused(Activity activity) {
              /* do nothing */
          }
  
          @Override
          public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
              /* do nothing */
          }
  
          @Override
          public void onActivityStarted(Activity activity) {
              /* do nothing */
          }
  
          @Override
          public void onActivityResumed(Activity activity) {
              /* do nothing */
          }
  
          @Override
          public void onActivityStopped(Activity activity) {
              /* do nothing */
          }
  
          @Override
          public void onActivitySaveInstanceState(Activity activity, Bundle outState) {
              /* do nothing */
          }
  
          @Override
          public void onActivityDestroyed(Activity activity) {
              // We really care only if the activity is being destroyed to
              // notify the the print spooler so it can close the print dialog.
              // Note the the spooler has a death recipient that observes if
              // this process gets killed so we cover the case of onDestroy not
              // being called due to this process being killed to reclaim memory.
              IPrintDocumentAdapterObserver observer = null;
              synchronized (mLock) {
                  if (activity == mActivity) {
                      observer = mObserver;
                      destroyLocked();
                  }
              }
              if (observer != null) {
                  try {
                      observer.onDestroy();
                  } catch (RemoteException re) {
                      Log.e(LOG_TAG, "Error announcing destroyed state", re);
                  }
              }
          }
  
          private boolean isDestroyedLocked() {
              return (mActivity == null);
          }
  
          private void destroyLocked() {
              mActivity.getApplication().unregisterActivityLifecycleCallbacks(
                      PrintDocumentAdapterDelegate.this);
              mActivity = null;
  
              mDocumentAdapter = null;
  
              // This method is only called from the main thread, so
              // clearing the messages guarantees that any time a
              // message is handled we are not in a destroyed state.
              mHandler.removeMessages(MyHandler.MSG_ON_START);
              mHandler.removeMessages(MyHandler.MSG_ON_LAYOUT);
              mHandler.removeMessages(MyHandler.MSG_ON_WRITE);
              mHandler.removeMessages(MyHandler.MSG_ON_FINISH);
              mHandler = null;
  
              mObserver = null;
  
              if (mPendingCallback != null) {
                  mPendingCallback.destroy();
                  mPendingCallback = null;
              }
          }
  
          private final class MyHandler extends Handler {
              public static final int MSG_ON_START = 1;
              public static final int MSG_ON_LAYOUT = 2;
              public static final int MSG_ON_WRITE = 3;
              public static final int MSG_ON_FINISH = 4;
              public static final int MSG_ON_KILL = 5;
  
              public MyHandler(Looper looper) {
                  super(looper, null, true);
              }
  
              @Override
              public void handleMessage(Message message) {
                  switch (message.what) {
                      case MSG_ON_START: {
                          if (DEBUG) {
                              Log.i(LOG_TAG, "onStart()");
                          }
  
                          ((PrintDocumentAdapter) message.obj).onStart();
                      } break;
  
                      case MSG_ON_LAYOUT: {
                          SomeArgs args = (SomeArgs) message.obj;
                          PrintDocumentAdapter adapter = (PrintDocumentAdapter) args.arg1;
                          PrintAttributes oldAttributes = (PrintAttributes) args.arg2;
                          PrintAttributes newAttributes = (PrintAttributes) args.arg3;
                          CancellationSignal cancellation = (CancellationSignal) args.arg4;
                          LayoutResultCallback callback = (LayoutResultCallback) args.arg5;
                          Bundle metadata = (Bundle) args.arg6;
                          args.recycle();
  
                          if (DEBUG) {
                              StringBuilder builder = new StringBuilder();
                              builder.append("PrintDocumentAdapter#onLayout() {\n");
                              builder.append("\n  oldAttributes:").append(oldAttributes);
                              builder.append("\n  newAttributes:").append(newAttributes);
                              builder.append("\n  preview:").append(metadata.getBoolean(
                                      PrintDocumentAdapter.EXTRA_PRINT_PREVIEW));
                              builder.append("\n}");
                              Log.i(LOG_TAG, builder.toString());
                          }
  
                          adapter.onLayout(oldAttributes, newAttributes, cancellation,
                                  callback, metadata);
                      } break;
  
                      case MSG_ON_WRITE: {
                          SomeArgs args = (SomeArgs) message.obj;
                          PrintDocumentAdapter adapter = (PrintDocumentAdapter) args.arg1;
                          PageRange[] pages = (PageRange[]) args.arg2;
                          ParcelFileDescriptor fd = (ParcelFileDescriptor) args.arg3;
                          CancellationSignal cancellation = (CancellationSignal) args.arg4;
                          WriteResultCallback callback = (WriteResultCallback) args.arg5;
                          args.recycle();
  
                          if (DEBUG) {
                              StringBuilder builder = new StringBuilder();
                              builder.append("PrintDocumentAdapter#onWrite() {\n");
                              builder.append("\n  pages:").append(Arrays.toString(pages));
                              builder.append("\n}");
                              Log.i(LOG_TAG, builder.toString());
                          }
  
                          adapter.onWrite(pages, fd, cancellation, callback);
                      } break;
  
                      case MSG_ON_FINISH: {
                          if (DEBUG) {
                              Log.i(LOG_TAG, "onFinish()");
                          }
  
                          ((PrintDocumentAdapter) message.obj).onFinish();
  
                          // Done printing, so destroy this instance as it
                          // should not be used anymore.
                          synchronized (mLock) {
                              destroyLocked();
                          }
                      } break;
  
                      case MSG_ON_KILL: {
                          if (DEBUG) {
                              Log.i(LOG_TAG, "onKill()");
                          }
  
                          String reason = (String) message.obj;
                          throw new RuntimeException(reason);
                      }
  
                      default: {
                          throw new IllegalArgumentException("Unknown message: "
                                  + message.what);
                      }
                  }
              }
          }
  
          private interface DestroyableCallback {
              public void destroy();
          }
  
          private final class MyLayoutResultCallback extends LayoutResultCallback
                  implements DestroyableCallback {
              private ILayoutResultCallback mCallback;
              private final int mSequence;
  
              public MyLayoutResultCallback(ILayoutResultCallback callback,
                      int sequence) {
                  mCallback = callback;
                  mSequence = sequence;
              }
  
              @Override
              public void onLayoutFinished(PrintDocumentInfo info, boolean changed) {
                  final ILayoutResultCallback callback;
                  synchronized (mLock) {
                      callback = mCallback;
                  }
  
                  // If the callback is null we are destroyed.
                  if (callback == null) {
                      Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
                              + "finish the printing activity before print completion "
                              + "or did you invoke a callback after finish?");
                      return;
                  }
  
                  try {
                      if (info == null) {
                          throw new NullPointerException("document info cannot be null");
                      }
  
                      try {
                          callback.onLayoutFinished(info, changed, mSequence);
                      } catch (RemoteException re) {
                          Log.e(LOG_TAG, "Error calling onLayoutFinished", re);
                      }
                  } finally {
                      destroy();
                  }
              }
  
              @Override
              public void onLayoutFailed(CharSequence error) {
                  final ILayoutResultCallback callback;
                  synchronized (mLock) {
                      callback = mCallback;
                  }
  
                  // If the callback is null we are destroyed.
                  if (callback == null) {
                      Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
                              + "finish the printing activity before print completion "
                              + "or did you invoke a callback after finish?");
                      return;
                  }
  
                  try {
                      callback.onLayoutFailed(error, mSequence);
                  } catch (RemoteException re) {
                      Log.e(LOG_TAG, "Error calling onLayoutFailed", re);
                  } finally {
                      destroy();
                  }
              }
  
              @Override
              public void onLayoutCancelled() {
                  final ILayoutResultCallback callback;
                  synchronized (mLock) {
                      callback = mCallback;
                  }
  
                  // If the callback is null we are destroyed.
                  if (callback == null) {
                      Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
                              + "finish the printing activity before print completion "
                              + "or did you invoke a callback after finish?");
                      return;
                  }
  
                  try {
                      callback.onLayoutCanceled(mSequence);
                  } catch (RemoteException re) {
                      Log.e(LOG_TAG, "Error calling onLayoutFailed", re);
                  } finally {
                      destroy();
                  }
              }
  
              @Override
              public void destroy() {
                  synchronized (mLock) {
                      mCallback = null;
                      mPendingCallback = null;
                  }
              }
          }
  
          private final class MyWriteResultCallback extends WriteResultCallback
                  implements DestroyableCallback {
              private ParcelFileDescriptor mFd;
              private IWriteResultCallback mCallback;
              private final int mSequence;
  
              public MyWriteResultCallback(IWriteResultCallback callback,
                      ParcelFileDescriptor fd, int sequence) {
                  mFd = fd;
                  mSequence = sequence;
                  mCallback = callback;
              }
  
              @Override
              public void onWriteFinished(PageRange[] pages) {
                  final IWriteResultCallback callback;
                  synchronized (mLock) {
                      callback = mCallback;
                  }
  
                  // If the callback is null we are destroyed.
                  if (callback == null) {
                      Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
                              + "finish the printing activity before print completion "
                              + "or did you invoke a callback after finish?");
                      return;
                  }
  
                  try {
                      if (pages == null) {
                          throw new IllegalArgumentException("pages cannot be null");
                      }
                      if (pages.length == 0) {
                          throw new IllegalArgumentException("pages cannot be empty");
                      }
  
                      try {
                          callback.onWriteFinished(pages, mSequence);
                      } catch (RemoteException re) {
                          Log.e(LOG_TAG, "Error calling onWriteFinished", re);
                      }
                  } finally {
                      destroy();
                  }
              }
  
              @Override
              public void onWriteFailed(CharSequence error) {
                  final IWriteResultCallback callback;
                  synchronized (mLock) {
                      callback = mCallback;
                  }
  
                  // If the callback is null we are destroyed.
                  if (callback == null) {
                      Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
                              + "finish the printing activity before print completion "
                              + "or did you invoke a callback after finish?");
                      return;
                  }
  
                  try {
                      callback.onWriteFailed(error, mSequence);
                  } catch (RemoteException re) {
                      Log.e(LOG_TAG, "Error calling onWriteFailed", re);
                  } finally {
                      destroy();
                  }
              }
  
              @Override
              public void onWriteCancelled() {
                  final IWriteResultCallback callback;
                  synchronized (mLock) {
                      callback = mCallback;
                  }
  
                  // If the callback is null we are destroyed.
                  if (callback == null) {
                      Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
                              + "finish the printing activity before print completion "
                              + "or did you invoke a callback after finish?");
                      return;
                  }
  
                  try {
                      callback.onWriteCanceled(mSequence);
                  } catch (RemoteException re) {
                      Log.e(LOG_TAG, "Error calling onWriteCanceled", re);
                  } finally {
                      destroy();
                  }
              }
  
              @Override
              public void destroy() {
                  synchronized (mLock) {
                      IoUtils.closeQuietly(mFd);
                      mCallback = null;
                      mFd = null;
                      mPendingCallback = null;
                  }
              }
          }
      }
  
      /**
       * @hide
       */
      public static final class PrintJobStateChangeListenerWrapper extends
              IPrintJobStateChangeListener.Stub {
          private final WeakReference<PrintJobStateChangeListener> mWeakListener;
          private final WeakReference<Handler> mWeakHandler;
  
          public PrintJobStateChangeListenerWrapper(PrintJobStateChangeListener listener,
                  Handler handler) {
              mWeakListener = new WeakReference<PrintJobStateChangeListener>(listener);
              mWeakHandler = new WeakReference<Handler>(handler);
          }
  
          @Override
          public void onPrintJobStateChanged(PrintJobId printJobId) {
              Handler handler = mWeakHandler.get();
              PrintJobStateChangeListener listener = mWeakListener.get();
              if (handler != null && listener != null) {
                  SomeArgs args = SomeArgs.obtain();
                  args.arg1 = this;
                  args.arg2 = printJobId;
                  handler.obtainMessage(MSG_NOTIFY_PRINT_JOB_STATE_CHANGED,
                          args).sendToTarget();
              }
          }
  
          public void destroy() {
              mWeakListener.clear();
          }
  
          public PrintJobStateChangeListener getListener() {
              return mWeakListener.get();
          }
      }
  
      /**
       * @hide
       */
      public static final class PrintServicesChangeListenerWrapper extends
              IPrintServicesChangeListener.Stub {
          private final WeakReference<PrintServicesChangeListener> mWeakListener;
          private final WeakReference<Handler> mWeakHandler;
  
          public PrintServicesChangeListenerWrapper(PrintServicesChangeListener listener,
                  Handler handler) {
              mWeakListener = new WeakReference<>(listener);
              mWeakHandler = new WeakReference<>(handler);
          }
  
          @Override
          public void onPrintServicesChanged() {
              Handler handler = mWeakHandler.get();
              PrintServicesChangeListener listener = mWeakListener.get();
              if (handler != null && listener != null) {
                  handler.post(listener::onPrintServicesChanged);
              }
          }
  
          public void destroy() {
              mWeakListener.clear();
          }
      }
  
      /**
       * @hide
       */
      public static final class PrintServiceRecommendationsChangeListenerWrapper extends
              IRecommendationsChangeListener.Stub {
          private final WeakReference<PrintServiceRecommendationsChangeListener> mWeakListener;
          private final WeakReference<Handler> mWeakHandler;
  
          public PrintServiceRecommendationsChangeListenerWrapper(
                  PrintServiceRecommendationsChangeListener listener, Handler handler) {
              mWeakListener = new WeakReference<>(listener);
              mWeakHandler = new WeakReference<>(handler);
          }
  
          @Override
          public void onRecommendationsChanged() {
              Handler handler = mWeakHandler.get();
              PrintServiceRecommendationsChangeListener listener = mWeakListener.get();
              if (handler != null && listener != null) {
                  handler.post(listener::onPrintServiceRecommendationsChanged);
              }
          }
  
          public void destroy() {
              mWeakListener.clear();
          }
      }
  }
  