1/*
2 * Copyright (C) 2017 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.googlecode.android_scripting.activity;
18
19import android.app.AlarmManager;
20import android.app.Notification;
21import android.app.PendingIntent;
22import android.content.Context;
23import android.content.Intent;
24import android.os.Binder;
25import android.os.IBinder;
26
27import com.google.common.base.Preconditions;
28import com.googlecode.android_scripting.BaseApplication;
29import com.googlecode.android_scripting.ForegroundService;
30import com.googlecode.android_scripting.IntentBuilders;
31import com.googlecode.android_scripting.NotificationIdFactory;
32import com.googlecode.android_scripting.R;
33import com.googlecode.android_scripting.event.Event;
34import com.googlecode.android_scripting.event.EventObserver;
35import com.googlecode.android_scripting.facade.EventFacade;
36import com.googlecode.android_scripting.facade.FacadeConfiguration;
37import com.googlecode.android_scripting.facade.FacadeManager;
38import com.googlecode.android_scripting.trigger.EventGenerationControllingObserver;
39import com.googlecode.android_scripting.trigger.Trigger;
40import com.googlecode.android_scripting.trigger.TriggerRepository;
41import com.googlecode.android_scripting.trigger.TriggerRepository.TriggerRepositoryObserver;
42
43/**
44 * The trigger service takes care of installing triggers serialized to the preference storage.
45 *
46 * <p>
47 * The service also installs an alarm that keeps it running, unless the user force-quits the
48 * service.
49 *
50 * <p>
51 * When no triggers are installed the service shuts down silently as to not consume resources
52 * unnecessarily.
53 *
54 */
55public class TriggerService extends ForegroundService {
56  private static final int NOTIFICATION_ID = NotificationIdFactory.create();
57  private static final long PING_MILLIS = 10 * 1000 * 60;
58
59  private final IBinder mBinder;
60  private TriggerRepository mTriggerRepository;
61  private FacadeManager mFacadeManager;
62  private EventFacade mEventFacade;
63
64  public class LocalBinder extends Binder {
65    public TriggerService getService() {
66      return TriggerService.this;
67    }
68  }
69
70  public TriggerService() {
71    super(NOTIFICATION_ID);
72    mBinder = new LocalBinder();
73  }
74
75  @Override
76  public IBinder onBind(Intent intent) {
77    return mBinder;
78  }
79
80  @Override
81  public void onCreate() {
82    super.onCreate();
83
84    mFacadeManager =
85        new FacadeManager(FacadeConfiguration.getSdkLevel(), this, null,
86            FacadeConfiguration.getFacadeClasses());
87    mEventFacade = mFacadeManager.getReceiver(EventFacade.class);
88
89    mTriggerRepository = ((BaseApplication) getApplication()).getTriggerRepository();
90    mTriggerRepository.bootstrapObserver(new RepositoryObserver());
91    mTriggerRepository.bootstrapObserver(new EventGenerationControllingObserver(mFacadeManager));
92    installAlarm();
93  }
94
95  @Override
96  public void onStart(Intent intent, int startId) {
97    if (mTriggerRepository.isEmpty()) {
98      stopSelfResult(startId);
99      return;
100    }
101  }
102
103  /** Returns the notification to display whenever the service is running. */
104  @Override
105  protected Notification createNotification() {
106    Intent notificationIntent = new Intent(this, TriggerManager.class);
107    Notification.Builder builder = new Notification.Builder(this);
108    builder.setSmallIcon(R.drawable.sl4a_logo_48)
109           .setTicker("SL4A Trigger Service started.")
110           .setWhen(System.currentTimeMillis())
111           .setContentTitle("SL4A Trigger Service")
112           .setContentText("Tap to view triggers")
113           .setContentIntent(PendingIntent.getActivity(this, 0, notificationIntent, 0));
114    Notification notification = builder.build();
115    notification.flags = Notification.FLAG_NO_CLEAR | Notification.FLAG_ONGOING_EVENT;
116    return notification;
117  }
118
119  private class TriggerEventObserver implements EventObserver {
120    private final Trigger mTrigger;
121
122    public TriggerEventObserver(Trigger trigger) {
123      mTrigger = trigger;
124    }
125
126    @Override
127    public void onEventReceived(Event event) {
128      mTrigger.handleEvent(event, TriggerService.this);
129    }
130  }
131
132  private class RepositoryObserver implements TriggerRepositoryObserver {
133    int mTriggerCount = 0;
134
135    @Override
136    public void onPut(Trigger trigger) {
137      mTriggerCount++;
138      mEventFacade.addNamedEventObserver(trigger.getEventName(), new TriggerEventObserver(trigger));
139    }
140
141    @Override
142    public void onRemove(Trigger trigger) {
143      Preconditions.checkArgument(mTriggerCount > 0);
144      // TODO(damonkohler): Tear down EventObserver associated with trigger.
145      if (--mTriggerCount == 0) {
146        // TODO(damonkohler): Use stopSelfResult() which would require tracking startId.
147        stopSelf();
148      }
149    }
150  }
151
152  private void installAlarm() {
153    AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
154    alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + PING_MILLIS,
155        PING_MILLIS, IntentBuilders.buildTriggerServicePendingIntent(this));
156  }
157
158  private void uninstallAlarm() {
159    AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
160    alarmManager.cancel(IntentBuilders.buildTriggerServicePendingIntent(this));
161  }
162
163  @Override
164  public void onDestroy() {
165    super.onDestroy();
166    uninstallAlarm();
167  }
168}
169