/*
 * Copyright (C) 2009 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.app.backup;

import android.app.backup.RestoreSet;
import android.app.backup.IRestoreObserver;

/**
 * Binder interface used by clients who wish to manage a restore operation.  Every
 * method in this interface requires the android.permission.BACKUP permission.
 *
 * {@hide}
 */
interface IRestoreSession {
    /**
     * Ask the current transport what the available restore sets are.
     *
     * @param observer This binder points to an object whose onRestoreSetsAvailable()
     *   method will be called to supply the results of the transport's lookup.
     * @return Zero on success; nonzero on error.  The observer will only receive a
     *   result callback if this method returned zero.
     */
    int getAvailableRestoreSets(IRestoreObserver observer);

    /**
     * Restore the given set onto the device, replacing the current data of any app
     * contained in the restore set with the data previously backed up.
     *
     * <p>Callers must hold the android.permission.BACKUP permission to use this method.
     *
     * @return Zero on success; nonzero on error.  The observer will only receive
     *   progress callbacks if this method returned zero.
     * @param token The token from {@link getAvailableRestoreSets()} corresponding to
     *   the restore set that should be used.
     * @param observer If non-null, this binder points to an object that will receive
     *   progress callbacks during the restore operation.
     */
    int restoreAll(long token, IRestoreObserver observer);

    /**
     * Restore select packages from the given set onto the device, replacing the
     * current data of any app contained in the set with the data previously
     * backed up.
     *
     * <p>Callers must hold the android.permission.BACKUP permission to use this method.
     *
     * @return Zero on success, nonzero on error. The observer will only receive
     *   progress callbacks if this method returned zero.
     * @param token The token from {@link getAvailableRestoreSets()} corresponding to
     *   the restore set that should be used.
     * @param observer If non-null, this binder points to an object that will receive
     *   progress callbacks during the restore operation.
     * @param packages The set of packages for which to attempt a restore.  Regardless of
     *   the contents of the actual back-end dataset named by {@code token}, only
     *   applications mentioned in this list will have their data restored.
     */
    int restoreSome(long token, IRestoreObserver observer, in String[] packages);

    /**
     * Restore a single application from backup.  The data will be restored from the
     * current backup dataset if the given package has stored data there, or from
     * the dataset used during the last full device setup operation if the current
     * backup dataset has no matching data.  If no backup data exists for this package
     * in either source, a nonzero value will be returned.
     *
     * @return Zero on success; nonzero on error.  The observer will only receive
     *   progress callbacks if this method returned zero.
     * @param packageName The name of the package whose data to restore.  If this is
     *   not the name of the caller's own package, then the android.permission.BACKUP
     *   permission must be held.
     * @param observer If non-null, this binder points to an object that will receive
     *   progress callbacks during the restore operation.
     */
    int restorePackage(in String packageName, IRestoreObserver observer);

    /**
     * End this restore session.  After this method is called, the IRestoreSession binder
     * is no longer valid.
     *
     * <p><b>Note:</b> The caller <i>must</i> invoke this method to end the restore session,
     *   even if {@link getAvailableRestoreSets} or {@link performRestore} failed.
     */
    void endRestoreSession();
}