NextAlarmTracker.java revision 3c984d67ebf07e1215c6b403f0e18e309f2604e9 
1/*
2 * Copyright (C) 2014 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
17package com.android.server.notification;
18
19import android.app.ActivityManager;
20import android.app.AlarmManager;
21import android.app.AlarmManager.AlarmClockInfo;
22import android.app.PendingIntent;
23import android.content.BroadcastReceiver;
24import android.content.Context;
25import android.content.Intent;
26import android.content.IntentFilter;
27import android.os.Handler;
28import android.os.Message;
29import android.os.PowerManager;
30import android.os.UserHandle;
31import android.text.format.DateFormat;
32import android.util.Log;
33import android.util.Slog;
34import android.util.TimeUtils;
35
36import com.android.server.notification.NotificationManagerService.DumpFilter;
37
38import java.io.PrintWriter;
39import java.util.ArrayList;
40import java.util.Locale;
41
42/** Helper for tracking updates to the current user's next alarm. */
43public class NextAlarmTracker {
44    private static final String TAG = "NextAlarmTracker";
45    private static final boolean DEBUG = Log.isLoggable(TAG, Log.DEBUG);
46
47    private static final String ACTION_TRIGGER = TAG + ".trigger";
48    private static final String EXTRA_TRIGGER = "trigger";
49    private static final int REQUEST_CODE = 100;
50
51    private static final long SECONDS = 1000;
52    private static final long MINUTES = 60 * SECONDS;
53    private static final long NEXT_ALARM_UPDATE_DELAY = 1 * SECONDS;  // treat clear+set as update
54    private static final long EARLY = 5 * SECONDS;  // fire early, ensure alarm stream is unmuted
55    private static final long WAIT_AFTER_INIT = 5 * MINUTES;// for initial alarm re-registration
56    private static final long WAIT_AFTER_BOOT = 20 * SECONDS;  // for initial alarm re-registration
57
58    private final Context mContext;
59    private final H mHandler = new H();
60    private final ArrayList<Callback> mCallbacks = new ArrayList<Callback>();
61
62    private long mInit;
63    private boolean mRegistered;
64    private AlarmManager mAlarmManager;
65    private int mCurrentUserId;
66    private long mScheduledAlarmTime;
67    private long mBootCompleted;
68    private PowerManager.WakeLock mWakeLock;
69
70    public NextAlarmTracker(Context context) {
71        mContext = context;
72    }
73
74    public void dump(PrintWriter pw, DumpFilter filter) {
75        pw.println("    NextAlarmTracker:");
76        pw.print("      len(mCallbacks)="); pw.println(mCallbacks.size());
77        pw.print("      mRegistered="); pw.println(mRegistered);
78        pw.print("      mInit="); pw.println(mInit);
79        pw.print("      mBootCompleted="); pw.println(mBootCompleted);
80        pw.print("      mCurrentUserId="); pw.println(mCurrentUserId);
81        pw.print("      mScheduledAlarmTime="); pw.println(formatAlarmDebug(mScheduledAlarmTime));
82        pw.print("      mWakeLock="); pw.println(mWakeLock);
83    }
84
85    public void addCallback(Callback callback) {
86        mCallbacks.add(callback);
87    }
88
89    public void removeCallback(Callback callback) {
90        mCallbacks.remove(callback);
91    }
92
93    public int getCurrentUserId() {
94        return mCurrentUserId;
95    }
96
97    public AlarmClockInfo getNextAlarm() {
98        return mAlarmManager.getNextAlarmClock(mCurrentUserId);
99    }
100
101    public void onUserSwitched() {
102        reset();
103    }
104
105    public void init() {
106        mAlarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);
107        final PowerManager p = (PowerManager) mContext.getSystemService(Context.POWER_SERVICE);
108        mWakeLock = p.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, TAG);
109        mInit = System.currentTimeMillis();
110        reset();
111    }
112
113    public void reset() {
114        if (mRegistered) {
115            mContext.unregisterReceiver(mReceiver);
116        }
117        mCurrentUserId = ActivityManager.getCurrentUser();
118        final IntentFilter filter = new IntentFilter();
119        filter.addAction(AlarmManager.ACTION_NEXT_ALARM_CLOCK_CHANGED);
120        filter.addAction(ACTION_TRIGGER);
121        filter.addAction(Intent.ACTION_TIME_CHANGED);
122        filter.addAction(Intent.ACTION_TIMEZONE_CHANGED);
123        filter.addAction(Intent.ACTION_BOOT_COMPLETED);
124        mContext.registerReceiverAsUser(mReceiver, new UserHandle(mCurrentUserId), filter, null,
125                null);
126        mRegistered = true;
127        evaluate();
128    }
129
130    public void destroy() {
131        if (mRegistered) {
132            mContext.unregisterReceiver(mReceiver);
133            mRegistered = false;
134        }
135    }
136
137    public void evaluate() {
138        mHandler.postEvaluate(0);
139    }
140
141    private void fireEvaluate(AlarmClockInfo nextAlarm, long wakeupTime, boolean booted) {
142        for (Callback callback : mCallbacks) {
143            callback.onEvaluate(nextAlarm, wakeupTime, booted);
144        }
145    }
146
147    private void handleEvaluate() {
148        final AlarmClockInfo nextAlarm = mAlarmManager.getNextAlarmClock(mCurrentUserId);
149        final long triggerTime = getEarlyTriggerTime(nextAlarm);
150        final long now = System.currentTimeMillis();
151        final boolean alarmUpcoming = triggerTime > now;
152        final boolean booted = isDoneWaitingAfterBoot(now);
153        if (DEBUG) Slog.d(TAG, "handleEvaluate nextAlarm=" + formatAlarmDebug(triggerTime)
154                + " alarmUpcoming=" + alarmUpcoming
155                + " booted=" + booted);
156        fireEvaluate(nextAlarm, triggerTime, booted);
157        if (!booted) {
158            // recheck after boot
159            final long recheckTime = (mBootCompleted > 0 ? mBootCompleted : now) + WAIT_AFTER_BOOT;
160            rescheduleAlarm(recheckTime);
161            return;
162        }
163        if (alarmUpcoming) {
164            // wake up just before the next alarm
165            rescheduleAlarm(triggerTime);
166        }
167    }
168
169    public static long getEarlyTriggerTime(AlarmClockInfo alarm) {
170        return alarm != null ? (alarm.getTriggerTime() - EARLY) : 0;
171    }
172
173    private boolean isDoneWaitingAfterBoot(long time) {
174        if (mBootCompleted > 0) return (time - mBootCompleted) > WAIT_AFTER_BOOT;
175        if (mInit > 0) return (time - mInit) > WAIT_AFTER_INIT;
176        return true;
177    }
178
179    public static String formatDuration(long millis) {
180        final StringBuilder sb = new StringBuilder();
181        TimeUtils.formatDuration(millis, sb);
182        return sb.toString();
183    }
184
185    public String formatAlarm(AlarmClockInfo alarm) {
186        return alarm != null ? formatAlarm(alarm.getTriggerTime()) : null;
187    }
188
189    private String formatAlarm(long time) {
190        return formatAlarm(time, "Hm", "hma");
191    }
192
193    private String formatAlarm(long time, String skeleton24, String skeleton12) {
194        final String skeleton = DateFormat.is24HourFormat(mContext) ? skeleton24 : skeleton12;
195        final String pattern = DateFormat.getBestDateTimePattern(Locale.getDefault(), skeleton);
196        return DateFormat.format(pattern, time).toString();
197    }
198
199    public String formatAlarmDebug(AlarmClockInfo alarm) {
200        return formatAlarmDebug(alarm != null ? alarm.getTriggerTime() : 0);
201    }
202
203    public String formatAlarmDebug(long time) {
204        if (time <= 0) return Long.toString(time);
205        return String.format("%s (%s)", time, formatAlarm(time, "Hms", "hmsa"));
206    }
207
208    private void rescheduleAlarm(long time) {
209        if (DEBUG) Slog.d(TAG, "rescheduleAlarm " + time);
210        final AlarmManager alarms = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);
211        final PendingIntent pendingIntent = PendingIntent.getBroadcast(mContext, REQUEST_CODE,
212                new Intent(ACTION_TRIGGER)
213                        .addFlags(Intent.FLAG_RECEIVER_FOREGROUND)
214                        .putExtra(EXTRA_TRIGGER, time),
215                PendingIntent.FLAG_UPDATE_CURRENT);
216        alarms.cancel(pendingIntent);
217        mScheduledAlarmTime = time;
218        if (time > 0) {
219            if (DEBUG) Slog.d(TAG, String.format("Scheduling alarm for %s (in %s)",
220                    formatAlarmDebug(time), formatDuration(time - System.currentTimeMillis())));
221            alarms.setExact(AlarmManager.RTC_WAKEUP, time, pendingIntent);
222        }
223    }
224
225    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
226        @Override
227        public void onReceive(Context context, Intent intent) {
228            final String action = intent.getAction();
229            if (DEBUG) Slog.d(TAG, "onReceive " + action);
230            long delay = 0;
231            if (action.equals(AlarmManager.ACTION_NEXT_ALARM_CLOCK_CHANGED)) {
232                delay = NEXT_ALARM_UPDATE_DELAY;
233                if (DEBUG) Slog.d(TAG, String.format("  next alarm for user %s: %s",
234                        mCurrentUserId,
235                        formatAlarmDebug(mAlarmManager.getNextAlarmClock(mCurrentUserId))));
236            } else if (action.equals(Intent.ACTION_BOOT_COMPLETED)) {
237                mBootCompleted = System.currentTimeMillis();
238            }
239            mHandler.postEvaluate(delay);
240            mWakeLock.acquire(delay + 5000);  // stay awake during evaluate
241        }
242    };
243
244    private class H extends Handler {
245        private static final int MSG_EVALUATE = 1;
246
247        public void postEvaluate(long delay) {
248            removeMessages(MSG_EVALUATE);
249            sendEmptyMessageDelayed(MSG_EVALUATE, delay);
250        }
251
252        @Override
253        public void handleMessage(Message msg) {
254            if (msg.what == MSG_EVALUATE) {
255                handleEvaluate();
256            }
257        }
258    }
259
260    public interface Callback {
261        void onEvaluate(AlarmClockInfo nextAlarm, long wakeupTime, boolean booted);
262    }
263}
264