1/*
2 * Copyright (C) 2012 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.contacts.util;
18
19import android.content.Context;
20import android.content.Intent;
21import android.content.pm.PackageInfo;
22import android.content.pm.PackageManager.NameNotFoundException;
23import android.net.Uri;
24import android.text.TextUtils;
25import android.util.Log;
26import android.view.MenuItem;
27
28import java.util.Locale;
29
30/**
31 * Functions to easily prepare contextual help menu option items with an intent that opens up the
32 * browser to a particular URL, while taking into account the preferred language and app version.
33 */
34public class HelpUtils {
35    private final static String TAG = HelpUtils.class.getName();
36
37    /**
38     * Help URL query parameter key for the preferred language.
39     */
40    private final static String PARAM_LANGUAGE_CODE = "hl";
41
42    /**
43     * Help URL query parameter key for the app version.
44     */
45    private final static String PARAM_VERSION = "version";
46
47    /**
48     * Cached version code to prevent repeated calls to the package manager.
49     */
50    private static String sCachedVersionCode = null;
51
52    /** Static helper that is not instantiable*/
53    private HelpUtils() { }
54
55    /**
56     * Prepares the help menu item by doing the following.
57     * - If the string corresponding to the helpUrlResourceId is empty or null, then the help menu
58     *   item is made invisible.
59     * - Otherwise, this makes the help menu item visible and sets the intent for the help menu
60     *   item to view the URL.
61     *
62     * @return returns whether the help menu item has been made visible.
63     */
64    public static boolean prepareHelpMenuItem(Context context, MenuItem helpMenuItem,
65            int helpUrlResourceId) {
66        String helpUrlString = context.getResources().getString(helpUrlResourceId);
67        return prepareHelpMenuItem(context, helpMenuItem, helpUrlString);
68    }
69
70    /**
71     * Prepares the help menu item by doing the following.
72     * - If the helpUrlString is empty or null, the help menu item is made invisible.
73     * - Otherwise, this makes the help menu item visible and sets the intent for the help menu
74     *   item to view the URL.
75     *
76     * @return returns whether the help menu item has been made visible.
77     */
78    public static boolean prepareHelpMenuItem(Context context, MenuItem helpMenuItem,
79            String helpUrlString) {
80        if (TextUtils.isEmpty(helpUrlString)) {
81            // The help url string is empty or null, so set the help menu item to be invisible.
82            helpMenuItem.setVisible(false);
83
84            // return that the help menu item is not visible (i.e. false)
85            return false;
86        } else {
87            // The help url string exists, so first add in some extra query parameters.
88            final Uri fullUri = uriWithAddedParameters(context, Uri.parse(helpUrlString));
89
90            // Then, create an intent that will be fired when the user
91            // selects this help menu item.
92            Intent intent = new Intent(Intent.ACTION_VIEW, fullUri);
93            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK
94                    | Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
95
96            // Set the intent to the help menu item, show the help menu item in the overflow
97            // menu, and make it visible.
98            helpMenuItem.setIntent(intent);
99            helpMenuItem.setShowAsAction(MenuItem.SHOW_AS_ACTION_NEVER);
100            helpMenuItem.setVisible(true);
101
102            // return that the help menu item is visible (i.e., true)
103            return true;
104        }
105    }
106
107    /**
108     * Adds two query parameters into the Uri, namely the language code and the version code
109     * of the app's package as gotten via the context.
110     * @return the uri with added query parameters
111     */
112    private static Uri uriWithAddedParameters(Context context, Uri baseUri) {
113        Uri.Builder builder = baseUri.buildUpon();
114
115        // Add in the preferred language
116        builder.appendQueryParameter(PARAM_LANGUAGE_CODE, Locale.getDefault().toString());
117
118        // Add in the package version code
119        if (sCachedVersionCode == null) {
120            // There is no cached version code, so try to get it from the package manager.
121            try {
122                // cache the version code
123                PackageInfo info = context.getPackageManager().getPackageInfo(
124                        context.getPackageName(), 0);
125                sCachedVersionCode = Integer.toString(info.versionCode);
126
127                // append the version code to the uri
128                builder.appendQueryParameter(PARAM_VERSION, sCachedVersionCode);
129            } catch (NameNotFoundException e) {
130                // Cannot find the package name, so don't add in the version parameter
131                // This shouldn't happen.
132                Log.wtf(TAG, "Invalid package name for context", e);
133            }
134        } else {
135            builder.appendQueryParameter(PARAM_VERSION, sCachedVersionCode);
136        }
137
138        // Build the full uri and return it
139        return builder.build();
140    }
141}
142