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
17package com.android.settings.applications;
18
19import android.content.ContentResolver;
20import android.content.Context;
21import android.content.Intent;
22import android.content.pm.ApplicationInfo;
23import android.content.pm.PackageInfo;
24import android.content.pm.PackageManager;
25import android.content.pm.ResolveInfo;
26import android.os.AsyncTask;
27import android.provider.Settings;
28import android.telephony.TelephonyManager;
29import android.text.TextUtils;
30import android.util.ArraySet;
31import android.util.AttributeSet;
32
33import com.android.settings.AppListPreference;
34
35import java.util.List;
36import java.util.Objects;
37import java.util.Set;
38
39/**
40 * A preference for choosing the default emergency app
41 */
42public class DefaultEmergencyPreference extends AppListPreference {
43
44    private final ContentResolver mContentResolver;
45
46    public static final Intent QUERY_INTENT = new Intent(
47            TelephonyManager.ACTION_EMERGENCY_ASSISTANCE);
48
49    public DefaultEmergencyPreference(Context context, AttributeSet attrs) {
50        super(context, attrs);
51        mContentResolver = context.getContentResolver();
52
53        if (isAvailable(context)) {
54            load();
55        }
56    }
57
58    @Override
59    protected boolean persistString(String value) {
60        String previousValue = Settings.Secure.getString(mContentResolver,
61                Settings.Secure.EMERGENCY_ASSISTANCE_APPLICATION);
62
63        if (!TextUtils.isEmpty(value) && !Objects.equals(value, previousValue)) {
64            Settings.Secure.putString(mContentResolver,
65                    Settings.Secure.EMERGENCY_ASSISTANCE_APPLICATION,
66                    value);
67        }
68        setSummary(getEntry());
69        return true;
70    }
71
72    private void load() {
73        new AsyncTask<Void, Void, Set<String>>() {
74            @Override
75            protected Set<String> doInBackground(Void[] params) {
76                return resolveAssistPackageAndQueryApps();
77            }
78
79            @Override
80            protected void onPostExecute(Set<String> entries) {
81                String currentPkg = Settings.Secure.getString(mContentResolver,
82                        Settings.Secure.EMERGENCY_ASSISTANCE_APPLICATION);
83                setPackageNames(entries.toArray(new String[entries.size()]), currentPkg);
84            }
85        }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
86    }
87
88    private Set<String> resolveAssistPackageAndQueryApps() {
89        Set<String> packages = new ArraySet<>();
90
91        PackageManager packageManager = getContext().getPackageManager();
92        List<ResolveInfo> infos = packageManager.queryIntentActivities(QUERY_INTENT, 0);
93
94        PackageInfo bestMatch = null;
95        final int size = infos.size();
96        for (int i = 0; i < size; i++) {
97            ResolveInfo info = infos.get(i);
98            if (info == null || info.activityInfo == null
99                    || packages.contains(info.activityInfo.packageName)) {
100                continue;
101            }
102
103            String packageName = info.activityInfo.packageName;
104
105            packages.add(packageName);
106
107            PackageInfo packageInfo;
108            try {
109                packageInfo = packageManager.getPackageInfo(packageName, 0);
110            } catch (PackageManager.NameNotFoundException e) {
111                continue;
112            }
113
114            // Get earliest installed app, but prioritize system apps.
115            if (bestMatch == null
116                    || !isSystemApp(bestMatch) && isSystemApp(packageInfo)
117                    || isSystemApp(bestMatch) == isSystemApp(packageInfo)
118                    && bestMatch.firstInstallTime > packageInfo.firstInstallTime) {
119                bestMatch = packageInfo;
120            }
121        }
122
123        String defaultPackage = Settings.Secure.getString(mContentResolver,
124                Settings.Secure.EMERGENCY_ASSISTANCE_APPLICATION);
125        boolean defaultMissing = TextUtils.isEmpty(defaultPackage)
126                || !packages.contains(defaultPackage);
127        if (bestMatch != null && defaultMissing) {
128            Settings.Secure.putString(mContentResolver,
129                    Settings.Secure.EMERGENCY_ASSISTANCE_APPLICATION,
130                    bestMatch.packageName);
131        }
132
133        return packages;
134    }
135
136    public static boolean isAvailable(Context context) {
137        return isCapable(context)
138                && context.getPackageManager().resolveActivity(QUERY_INTENT, 0) != null;
139    }
140
141    public static boolean isCapable(Context context) {
142        return TelephonyManager.EMERGENCY_ASSISTANCE_ENABLED
143                && context.getResources().getBoolean(
144                com.android.internal.R.bool.config_voice_capable);
145    }
146
147    private static boolean isSystemApp(PackageInfo info) {
148        return info.applicationInfo != null
149                && (info.applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0;
150    }
151}
152