1/*
2 * Copyright (C) 2008 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.systemui.statusbar.policy;
18
19import android.app.ActivityManager;
20import android.app.AppOpsManager;
21import android.app.StatusBarManager;
22import android.content.BroadcastReceiver;
23import android.content.ContentResolver;
24import android.content.Context;
25import android.content.Intent;
26import android.content.IntentFilter;
27import android.database.ContentObserver;
28import android.location.LocationManager;
29import android.os.Handler;
30import android.os.UserHandle;
31import android.os.UserManager;
32import android.provider.Settings;
33
34import com.android.systemui.R;
35
36import java.util.ArrayList;
37import java.util.List;
38
39/**
40 * A controller to manage changes of location related states and update the views accordingly.
41 */
42public class LocationController extends BroadcastReceiver {
43    // The name of the placeholder corresponding to the location request status icon.
44    // This string corresponds to config_statusBarIcons in core/res/res/values/config.xml.
45    public static final String LOCATION_STATUS_ICON_PLACEHOLDER = "location";
46    public static final int LOCATION_STATUS_ICON_ID
47        = R.drawable.stat_sys_device_access_location_found;
48
49    private static final int[] mHighPowerRequestAppOpArray
50        = new int[] {AppOpsManager.OP_MONITOR_HIGH_POWER_LOCATION};
51
52    private Context mContext;
53
54    private AppOpsManager mAppOpsManager;
55    private StatusBarManager mStatusBarManager;
56
57    private boolean mAreActiveLocationRequests;
58
59    private ArrayList<LocationSettingsChangeCallback> mSettingsChangeCallbacks =
60            new ArrayList<LocationSettingsChangeCallback>();
61
62    /**
63     * A callback for change in location settings (the user has enabled/disabled location).
64     */
65    public interface LocationSettingsChangeCallback {
66        /**
67         * Called whenever location settings change.
68         *
69         * @param locationEnabled A value of true indicates that at least one type of location
70         *                        is enabled in settings.
71         */
72        public void onLocationSettingsChanged(boolean locationEnabled);
73    }
74
75    public LocationController(Context context) {
76        mContext = context;
77
78        IntentFilter filter = new IntentFilter();
79        filter.addAction(LocationManager.HIGH_POWER_REQUEST_CHANGE_ACTION);
80        context.registerReceiver(this, filter);
81
82        mAppOpsManager = (AppOpsManager) context.getSystemService(Context.APP_OPS_SERVICE);
83        mStatusBarManager
84                = (StatusBarManager) context.getSystemService(Context.STATUS_BAR_SERVICE);
85
86        // Register to listen for changes in location settings.
87        IntentFilter intentFilter = new IntentFilter();
88        intentFilter.addAction(LocationManager.MODE_CHANGED_ACTION);
89        context.registerReceiverAsUser(new BroadcastReceiver() {
90            @Override
91            public void onReceive(Context context, Intent intent) {
92                String action = intent.getAction();
93                if (LocationManager.MODE_CHANGED_ACTION.equals(action)) {
94                    locationSettingsChanged();
95                }
96            }
97        }, UserHandle.ALL, intentFilter, null, new Handler());
98
99        // Examine the current location state and initialize the status view.
100        updateActiveLocationRequests();
101        refreshViews();
102    }
103
104    /**
105     * Add a callback to listen for changes in location settings.
106     */
107    public void addSettingsChangedCallback(LocationSettingsChangeCallback cb) {
108        mSettingsChangeCallbacks.add(cb);
109    }
110
111    /**
112     * Enable or disable location in settings.
113     *
114     * <p>This will attempt to enable/disable every type of location setting
115     * (e.g. high and balanced power).
116     *
117     * <p>If enabling, a user consent dialog will pop up prompting the user to accept.
118     * If the user doesn't accept, network location won't be enabled.
119     *
120     * @return true if attempt to change setting was successful.
121     */
122    public boolean setLocationEnabled(boolean enabled) {
123        int currentUserId = ActivityManager.getCurrentUser();
124        if (isUserLocationRestricted(currentUserId)) {
125            return false;
126        }
127        final ContentResolver cr = mContext.getContentResolver();
128        // When enabling location, a user consent dialog will pop up, and the
129        // setting won't be fully enabled until the user accepts the agreement.
130        int mode = enabled
131                ? Settings.Secure.LOCATION_MODE_HIGH_ACCURACY : Settings.Secure.LOCATION_MODE_OFF;
132        // QuickSettings always runs as the owner, so specifically set the settings
133        // for the current foreground user.
134        return Settings.Secure
135                .putIntForUser(cr, Settings.Secure.LOCATION_MODE, mode, currentUserId);
136    }
137
138    /**
139     * Returns true if location isn't disabled in settings.
140     */
141    public boolean isLocationEnabled() {
142        ContentResolver resolver = mContext.getContentResolver();
143        // QuickSettings always runs as the owner, so specifically retrieve the settings
144        // for the current foreground user.
145        int mode = Settings.Secure.getIntForUser(resolver, Settings.Secure.LOCATION_MODE,
146                Settings.Secure.LOCATION_MODE_OFF, ActivityManager.getCurrentUser());
147        return mode != Settings.Secure.LOCATION_MODE_OFF;
148    }
149
150    /**
151     * Returns true if the current user is restricted from using location.
152     */
153    private boolean isUserLocationRestricted(int userId) {
154        final UserManager um = (UserManager) mContext.getSystemService(Context.USER_SERVICE);
155        return um.hasUserRestriction(
156                UserManager.DISALLOW_SHARE_LOCATION,
157                new UserHandle(userId));
158    }
159
160    /**
161     * Returns true if there currently exist active high power location requests.
162     */
163    private boolean areActiveHighPowerLocationRequests() {
164        List<AppOpsManager.PackageOps> packages
165            = mAppOpsManager.getPackagesForOps(mHighPowerRequestAppOpArray);
166        // AppOpsManager can return null when there is no requested data.
167        if (packages != null) {
168            final int numPackages = packages.size();
169            for (int packageInd = 0; packageInd < numPackages; packageInd++) {
170                AppOpsManager.PackageOps packageOp = packages.get(packageInd);
171                List<AppOpsManager.OpEntry> opEntries = packageOp.getOps();
172                if (opEntries != null) {
173                    final int numOps = opEntries.size();
174                    for (int opInd = 0; opInd < numOps; opInd++) {
175                        AppOpsManager.OpEntry opEntry = opEntries.get(opInd);
176                        // AppOpsManager should only return OP_MONITOR_HIGH_POWER_LOCATION because
177                        // of the mHighPowerRequestAppOpArray filter, but checking defensively.
178                        if (opEntry.getOp() == AppOpsManager.OP_MONITOR_HIGH_POWER_LOCATION) {
179                            if (opEntry.isRunning()) {
180                                return true;
181                            }
182                        }
183                    }
184                }
185            }
186        }
187
188        return false;
189    }
190
191    // Updates the status view based on the current state of location requests.
192    private void refreshViews() {
193        if (mAreActiveLocationRequests) {
194            mStatusBarManager.setIcon(LOCATION_STATUS_ICON_PLACEHOLDER, LOCATION_STATUS_ICON_ID, 0,
195                    mContext.getString(R.string.accessibility_location_active));
196        } else {
197            mStatusBarManager.removeIcon(LOCATION_STATUS_ICON_PLACEHOLDER);
198        }
199    }
200
201    // Reads the active location requests and updates the status view if necessary.
202    private void updateActiveLocationRequests() {
203        boolean hadActiveLocationRequests = mAreActiveLocationRequests;
204        mAreActiveLocationRequests = areActiveHighPowerLocationRequests();
205        if (mAreActiveLocationRequests != hadActiveLocationRequests) {
206            refreshViews();
207        }
208    }
209
210    private void locationSettingsChanged() {
211        boolean isEnabled = isLocationEnabled();
212        for (LocationSettingsChangeCallback cb : mSettingsChangeCallbacks) {
213            cb.onLocationSettingsChanged(isEnabled);
214        }
215    }
216
217    @Override
218    public void onReceive(Context context, Intent intent) {
219        final String action = intent.getAction();
220        if (LocationManager.HIGH_POWER_REQUEST_CHANGE_ACTION.equals(action)) {
221            updateActiveLocationRequests();
222        }
223    }
224}
225