1/*
2 * Copyright (C) 2007 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;
18
19import android.app.Activity;
20import android.app.LoaderManager;
21import android.content.ActivityNotFoundException;
22import android.content.ContentResolver;
23import android.content.Context;
24import android.content.Intent;
25import android.content.Loader;
26import android.net.Uri;
27import android.os.Bundle;
28import android.os.StrictMode;
29import android.os.SystemProperties;
30import android.support.annotation.VisibleForTesting;
31import android.support.v4.content.FileProvider;
32import android.text.TextUtils;
33import android.util.Log;
34import android.widget.Toast;
35
36import com.android.settings.users.RestrictedProfileSettings;
37
38import java.io.File;
39import java.util.ArrayList;
40import java.util.List;
41
42/**
43 * The "dialog" that shows from "License" in the Settings app.
44 */
45public class SettingsLicenseActivity extends Activity implements
46            LoaderManager.LoaderCallbacks<File> {
47    private static final String TAG = "SettingsLicenseActivity";
48
49    private static final String DEFAULT_LICENSE_PATH = "/system/etc/NOTICE.html.gz";
50    private static final String PROPERTY_LICENSE_PATH = "ro.config.license_path";
51
52    private static final int LOADER_ID_LICENSE_HTML_LOADER = 0;
53
54    @Override
55    protected void onCreate(Bundle savedInstanceState) {
56        super.onCreate(savedInstanceState);
57
58        final String licenseHtmlPath =
59                SystemProperties.get(PROPERTY_LICENSE_PATH, DEFAULT_LICENSE_PATH);
60        if (isFilePathValid(licenseHtmlPath)) {
61            showSelectedFile(licenseHtmlPath);
62        } else {
63            showHtmlFromDefaultXmlFiles();
64        }
65    }
66
67    @Override
68    public Loader<File> onCreateLoader(int id, Bundle args) {
69        return new LicenseHtmlLoader(this);
70    }
71
72    @Override
73    public void onLoadFinished(Loader<File> loader, File generatedHtmlFile) {
74        showGeneratedHtmlFile(generatedHtmlFile);
75    }
76
77    @Override
78    public void onLoaderReset(Loader<File> loader) {
79    }
80
81    private void showHtmlFromDefaultXmlFiles() {
82        getLoaderManager().initLoader(LOADER_ID_LICENSE_HTML_LOADER, Bundle.EMPTY, this);
83    }
84
85    @VisibleForTesting
86    Uri getUriFromGeneratedHtmlFile(File generatedHtmlFile) {
87        return FileProvider.getUriForFile(this, RestrictedProfileSettings.FILE_PROVIDER_AUTHORITY,
88                generatedHtmlFile);
89    }
90
91    private void showGeneratedHtmlFile(File generatedHtmlFile) {
92        if (generatedHtmlFile != null) {
93            showHtmlFromUri(getUriFromGeneratedHtmlFile(generatedHtmlFile));
94        } else {
95            Log.e(TAG, "Failed to generate.");
96            showErrorAndFinish();
97        }
98    }
99
100    private void showSelectedFile(final String path) {
101        if (TextUtils.isEmpty(path)) {
102            Log.e(TAG, "The system property for the license file is empty");
103            showErrorAndFinish();
104            return;
105        }
106
107        final File file = new File(path);
108        if (!isFileValid(file)) {
109            Log.e(TAG, "License file " + path + " does not exist");
110            showErrorAndFinish();
111            return;
112        }
113        showHtmlFromUri(Uri.fromFile(file));
114     }
115
116     private void showHtmlFromUri(Uri uri) {
117        // Kick off external viewer due to WebView security restrictions; we
118        // carefully point it at HTMLViewer, since it offers to decompress
119        // before viewing.
120        final Intent intent = new Intent(Intent.ACTION_VIEW);
121        intent.setDataAndType(uri, "text/html");
122        intent.putExtra(Intent.EXTRA_TITLE, getString(R.string.settings_license_activity_title));
123        if (ContentResolver.SCHEME_CONTENT.equals(uri.getScheme())) {
124            intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
125        }
126        intent.addCategory(Intent.CATEGORY_DEFAULT);
127        intent.setPackage("com.android.htmlviewer");
128
129        try {
130            startActivity(intent);
131            finish();
132        } catch (ActivityNotFoundException e) {
133            Log.e(TAG, "Failed to find viewer", e);
134            showErrorAndFinish();
135        }
136    }
137
138    private void showErrorAndFinish() {
139        Toast.makeText(this, R.string.settings_license_activity_unavailable, Toast.LENGTH_LONG)
140                .show();
141        finish();
142    }
143
144    private boolean isFilePathValid(final String path) {
145        return !TextUtils.isEmpty(path) && isFileValid(new File(path));
146    }
147
148    @VisibleForTesting
149    boolean isFileValid(final File file) {
150        return file.exists() && file.length() != 0;
151    }
152}
153