1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.deskclock;
18 
19 import android.app.AlarmManager;
20 import android.app.PendingIntent;
21 import android.app.backup.BackupAgent;
22 import android.app.backup.BackupDataInput;
23 import android.app.backup.BackupDataOutput;
24 import android.content.ContentResolver;
25 import android.content.Context;
26 import android.content.Intent;
27 import android.os.ParcelFileDescriptor;
28 import android.os.SystemClock;
29 import androidx.annotation.NonNull;
30 
31 import com.android.deskclock.alarms.AlarmStateManager;
32 import com.android.deskclock.data.DataModel;
33 import com.android.deskclock.provider.Alarm;
34 import com.android.deskclock.provider.AlarmInstance;
35 
36 import java.io.File;
37 import java.io.IOException;
38 import java.util.Calendar;
39 import java.util.List;
40 
41 public class DeskClockBackupAgent extends BackupAgent {
42 
43     private static final LogUtils.Logger LOGGER = new LogUtils.Logger("DeskClockBackupAgent");
44 
45     public static final String ACTION_COMPLETE_RESTORE =
46             "com.android.deskclock.action.COMPLETE_RESTORE";
47 
48     @Override
onBackup(ParcelFileDescriptor oldState, BackupDataOutput data, ParcelFileDescriptor newState)49     public void onBackup(ParcelFileDescriptor oldState, BackupDataOutput data,
50             ParcelFileDescriptor newState) throws IOException { }
51 
52     @Override
onRestore(BackupDataInput data, int appVersionCode, ParcelFileDescriptor newState)53     public void onRestore(BackupDataInput data, int appVersionCode,
54             ParcelFileDescriptor newState) throws IOException { }
55 
56     @Override
onRestoreFile(@onNull ParcelFileDescriptor data, long size, File destination, int type, long mode, long mtime)57     public void onRestoreFile(@NonNull ParcelFileDescriptor data, long size, File destination,
58             int type, long mode, long mtime) throws IOException {
59         // The preference file on the backup device may not be the same on the restore device.
60         // Massage the file name here before writing it.
61         if (destination.getName().endsWith("_preferences.xml")) {
62             final String prefFileName = getPackageName() + "_preferences.xml";
63             destination = new File(destination.getParentFile(), prefFileName);
64         }
65 
66         super.onRestoreFile(data, size, destination, type, mode, mtime);
67     }
68 
69     /**
70      * When this method is called during backup/restore, the application is executing in a
71      * "minimalist" state. Because of this, the application's ContentResolver cannot be used.
72      * Consequently, the work of scheduling alarms on the restore device cannot be done here.
73      * Instead, a future callback to DeskClock is used as a signal to reschedule the alarms. The
74      * future callback may take the form of ACTION_BOOT_COMPLETED if the device is not yet fully
75      * booted (i.e. the restore occurred as part of the setup wizard). If the device is booted, an
76      * ACTION_COMPLETE_RESTORE broadcast is scheduled 10 seconds in the future to give
77      * backup/restore enough time to kill the Clock process. Both of these future callbacks result
78      * in the execution of {@link #processRestoredData(Context)}.
79      */
80     @Override
onRestoreFinished()81     public void onRestoreFinished() {
82         if (Utils.isNOrLater()) {
83             // TODO: migrate restored database and preferences over into
84             // the device-encrypted storage area
85         }
86 
87         // Indicate a data restore has been completed.
88         DataModel.getDataModel().setRestoreBackupFinished(true);
89 
90         // Create an Intent to send into DeskClock indicating restore is complete.
91         final PendingIntent restoreIntent = PendingIntent.getBroadcast(this, 0,
92                 new Intent(ACTION_COMPLETE_RESTORE).setClass(this, AlarmInitReceiver.class),
93                 PendingIntent.FLAG_ONE_SHOT | PendingIntent.FLAG_CANCEL_CURRENT);
94 
95         // Deliver the Intent 10 seconds from now.
96         final long triggerAtMillis = SystemClock.elapsedRealtime() + 10000;
97 
98         // Schedule the Intent delivery in AlarmManager.
99         final AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
100         alarmManager.setExact(AlarmManager.ELAPSED_REALTIME_WAKEUP, triggerAtMillis, restoreIntent);
101 
102         LOGGER.i("Waiting for %s to complete the data restore", ACTION_COMPLETE_RESTORE);
103     }
104 
105     /**
106      * @param context a context to access resources and services
107      * @return {@code true} if restore data was processed; {@code false} otherwise.
108      */
processRestoredData(Context context)109     public static boolean processRestoredData(Context context) {
110         // If data was not recently restored, there is nothing to do.
111         if (!DataModel.getDataModel().isRestoreBackupFinished()) {
112             return false;
113         }
114 
115         LOGGER.i("processRestoredData() started");
116 
117         // Now that alarms have been restored, schedule new instances in AlarmManager.
118         final ContentResolver contentResolver = context.getContentResolver();
119         final List<Alarm> alarms = Alarm.getAlarms(contentResolver, null);
120 
121         final Calendar now = Calendar.getInstance();
122         for (Alarm alarm : alarms) {
123             // Remove any instances that may currently exist for the alarm;
124             // these aren't relevant on the restore device and we'll recreate them below.
125             AlarmStateManager.deleteAllInstances(context, alarm.id);
126 
127             if (alarm.enabled) {
128                 // Create the next alarm instance to schedule.
129                 AlarmInstance alarmInstance = alarm.createInstanceAfter(now);
130 
131                 // Add the next alarm instance to the database.
132                 alarmInstance = AlarmInstance.addInstance(contentResolver, alarmInstance);
133 
134                 // Schedule the next alarm instance in AlarmManager.
135                 AlarmStateManager.registerInstance(context, alarmInstance, true);
136                 LOGGER.i("DeskClockBackupAgent scheduled alarm instance: %s", alarmInstance);
137             }
138         }
139 
140         // Remove the preference to avoid executing this logic multiple times.
141         DataModel.getDataModel().setRestoreBackupFinished(false);
142 
143         LOGGER.i("processRestoredData() completed");
144         return true;
145     }
146 }
147