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.messaging.util;
18
19import android.content.ContentResolver;
20import android.content.Context;
21import android.net.Uri;
22import android.os.Environment;
23import android.text.TextUtils;
24import android.webkit.MimeTypeMap;
25
26import com.android.messaging.Factory;
27import com.android.messaging.R;
28import com.google.common.io.Files;
29
30import java.io.File;
31import java.io.IOException;
32import java.text.SimpleDateFormat;
33import java.util.Date;
34import java.util.Locale;
35
36public class FileUtil {
37    /** Returns a new file name, ensuring that such a file does not already exist. */
38    private static synchronized File getNewFile(File directory, String extension,
39            String fileNameFormat) throws IOException {
40        final Date date = new Date(System.currentTimeMillis());
41        final SimpleDateFormat dateFormat = new SimpleDateFormat(fileNameFormat);
42        final String numberedFileNameFormat = dateFormat.format(date) + "_%02d" + "." + extension;
43        for (int i = 1; i <= 99; i++) { // Only save 99 of the same file name.
44            final String newName = String.format(Locale.US, numberedFileNameFormat, i);
45            File testFile = new File(directory, newName);
46            if (!testFile.exists()) {
47                testFile.createNewFile();
48                return testFile;
49            }
50        }
51        LogUtil.e(LogUtil.BUGLE_TAG, "Too many duplicate file names: " + numberedFileNameFormat);
52        return null;
53    }
54
55    /**
56     * Creates an unused name to use for creating a new file. The format happens to be similar
57     * to that used by the Android camera application.
58     *
59     * @param directory directory that the file should be saved to
60     * @param contentType of the media being saved
61     * @return file name to be used for creating the new file. The caller is responsible for
62     *   actually creating the file.
63     */
64    public static File getNewFile(File directory, String contentType) throws IOException {
65        MimeTypeMap mimeTypeMap = MimeTypeMap.getSingleton();
66        String fileExtension = mimeTypeMap.getExtensionFromMimeType(contentType);
67
68        final Context context = Factory.get().getApplicationContext();
69        String fileNameFormat = context.getString(ContentType.isImageType(contentType)
70                ? R.string.new_image_file_name_format : R.string.new_file_name_format);
71        return getNewFile(directory, fileExtension, fileNameFormat);
72    }
73
74    /** Delete everything below and including root */
75    public static void removeFileOrDirectory(File root) {
76        removeFileOrDirectoryExcept(root, null);
77    }
78
79    /** Delete everything below and including root except for the given file */
80    public static void removeFileOrDirectoryExcept(File root, File exclude) {
81        if (root.exists()) {
82            if (root.isDirectory()) {
83                for (File file : root.listFiles()) {
84                    if (exclude == null || !file.equals(exclude)) {
85                        removeFileOrDirectoryExcept(file, exclude);
86                    }
87                }
88                root.delete();
89            } else if (root.isFile()) {
90                root.delete();
91            }
92        }
93    }
94
95    /**
96     * Move all files and folders under a directory into the target.
97     */
98    public static void moveAllContentUnderDirectory(File sourceDir, File targetDir) {
99        if (sourceDir.isDirectory() && targetDir.isDirectory()) {
100            if (isSameOrSubDirectory(sourceDir, targetDir)) {
101                LogUtil.e(LogUtil.BUGLE_TAG, "Can't move directory content since the source " +
102                        "directory is a parent of the target");
103                return;
104            }
105            for (File file : sourceDir.listFiles()) {
106                if (file.isDirectory()) {
107                    final File dirTarget = new File(targetDir, file.getName());
108                    dirTarget.mkdirs();
109                    moveAllContentUnderDirectory(file, dirTarget);
110                } else {
111                    try {
112                        final File fileTarget = new File(targetDir, file.getName());
113                        Files.move(file, fileTarget);
114                    } catch (IOException e) {
115                        LogUtil.e(LogUtil.BUGLE_TAG, "Failed to move files", e);
116                        // Try proceed with the next file.
117                    }
118                }
119            }
120        }
121    }
122
123    private static boolean isFileUri(final Uri uri) {
124        return TextUtils.equals(uri.getScheme(), ContentResolver.SCHEME_FILE);
125    }
126
127    // Checks if the file is in /data, and don't allow any app to send personal information.
128    // We're told it's possible to create world readable hardlinks to other apps private data
129    // so we ban all /data file uris.
130    public static boolean isInPrivateDir(Uri uri) {
131        if (!isFileUri(uri)) {
132            return false;
133        }
134        final File file = new File(uri.getPath());
135        return FileUtil.isSameOrSubDirectory(Environment.getDataDirectory(), file);
136    }
137
138    /**
139     * Checks, whether the child directory is the same as, or a sub-directory of the base
140     * directory.
141     */
142    private static boolean isSameOrSubDirectory(File base, File child) {
143        try {
144            base = base.getCanonicalFile();
145            child = child.getCanonicalFile();
146            File parentFile = child;
147            while (parentFile != null) {
148                if (base.equals(parentFile)) {
149                    return true;
150                }
151                parentFile = parentFile.getParentFile();
152            }
153            return false;
154        } catch (IOException ex) {
155            LogUtil.e(LogUtil.BUGLE_TAG, "Error while accessing file", ex);
156            return false;
157        }
158    }
159}
160