2 * Copyright © 2020 Soren Stoutner <soren@stoutner.com>.
4 * This file is part of Privacy Browser <https://www.stoutner.com/privacy-browser>.
6 * Privacy Browser is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * Privacy Browser is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with Privacy Browser. If not, see <http://www.gnu.org/licenses/>.
20 package com.stoutner.privacybrowser.asynctasks;
22 import android.app.Activity;
23 import android.content.Context;
24 import android.net.Uri;
25 import android.os.AsyncTask;
26 import android.webkit.CookieManager;
27 import android.webkit.MimeTypeMap;
29 import androidx.fragment.app.DialogFragment;
30 import androidx.fragment.app.FragmentManager;
32 import com.stoutner.privacybrowser.R;
33 import com.stoutner.privacybrowser.dialogs.SaveWebpageDialog;
34 import com.stoutner.privacybrowser.helpers.ProxyHelper;
36 import java.lang.ref.WeakReference;
37 import java.net.HttpURLConnection;
38 import java.net.Proxy;
40 import java.text.NumberFormat;
42 public class PrepareSaveDialog extends AsyncTask<String, Void, String[]> {
43 // Define weak references.
44 private WeakReference<Activity> activityWeakReference;
45 private WeakReference<Context> contextWeakReference;
46 private WeakReference<FragmentManager> fragmentManagerWeakReference;
48 // Define the class variables.
50 private String userAgent;
51 private boolean cookiesEnabled;
52 private String urlString;
54 // The public constructor.
55 public PrepareSaveDialog(Activity activity, Context context, FragmentManager fragmentManager, int saveType, String userAgent, boolean cookiesEnabled) {
56 // Populate the weak references.
57 activityWeakReference = new WeakReference<>(activity);
58 contextWeakReference = new WeakReference<>(context);
59 fragmentManagerWeakReference = new WeakReference<>(fragmentManager);
61 // Store the class variables.
62 this.saveType = saveType;
63 this.userAgent = userAgent;
64 this.cookiesEnabled = cookiesEnabled;
68 protected String[] doInBackground(String... urlToSave) {
69 // Get a handle for the activity and context.
70 Activity activity = activityWeakReference.get();
71 Context context = contextWeakReference.get();
73 // Abort if the activity is gone.
74 if (activity == null || activity.isFinishing()) {
75 // Return a null string array.
79 // Get the URL string.
80 urlString = urlToSave[0];
82 // Define the file name string.
83 String fileNameString;
85 // Initialize the formatted file size string.
86 String formattedFileSize = context.getString(R.string.unknown_size);
88 // Because everything relating to requesting data from a webserver can throw errors, the entire section must catch exceptions.
90 // Convert the URL string to a URL.
91 URL url = new URL(urlString);
93 // Instantiate the proxy helper.
94 ProxyHelper proxyHelper = new ProxyHelper();
96 // Get the current proxy.
97 Proxy proxy = proxyHelper.getCurrentProxy(context);
99 // Open a connection to the URL. No data is actually sent at this point.
100 HttpURLConnection httpUrlConnection = (HttpURLConnection) url.openConnection(proxy);
102 // Add the user agent to the header property.
103 httpUrlConnection.setRequestProperty("User-Agent", userAgent);
105 // Add the cookies if they are enabled.
106 if (cookiesEnabled) {
107 // Get the cookies for the current domain.
108 String cookiesString = CookieManager.getInstance().getCookie(url.toString());
110 // only add the cookies if they are not null.
111 if (cookiesString != null) {
112 // Add the cookies to the header property.
113 httpUrlConnection.setRequestProperty("Cookie", cookiesString);
117 // The actual network request is in a `try` bracket so that `disconnect()` is run in the `finally` section even if an error is encountered in the main block.
119 // Get the status code. This initiates a network connection.
120 int responseCode = httpUrlConnection.getResponseCode();
122 // Check the response code.
123 if (responseCode >= 400) { // The response code is an error message.
124 // Set the formatted file size to indicate a bad URL.
125 formattedFileSize = context.getString(R.string.invalid_url);
127 // Set the file name according to the URL.
128 fileNameString = getFileNameFromUrl(context, urlString, null);
129 } else { // The response code is not an error message.
131 String contentLengthString = httpUrlConnection.getHeaderField("Content-Length");
132 String contentDispositionString = httpUrlConnection.getHeaderField("Content-Disposition");
133 String contentTypeString = httpUrlConnection.getContentType();
135 // Remove anything after the MIME type in the content type string.
136 if (contentTypeString.contains(";")) {
137 // Remove everything beginning with the `;`.
138 contentTypeString = contentTypeString.substring(0, contentTypeString.indexOf(";"));
141 // Only process the content length string if it isn't null.
142 if (contentLengthString != null) {
143 // Convert the content length string to a long.
144 long fileSize = Long.parseLong(contentLengthString);
146 // Format the file size.
147 formattedFileSize = NumberFormat.getInstance().format(fileSize) + " " + context.getString(R.string.bytes);
150 // Get the file name string from the content disposition.
151 fileNameString = getFileNameFromHeaders(context, contentDispositionString, contentTypeString, urlString);
154 // Disconnect the HTTP URL connection.
155 httpUrlConnection.disconnect();
157 } catch (Exception exception) {
158 // Set the formatted file size to indicate a bad URL.
159 formattedFileSize = context.getString(R.string.invalid_url);
161 // Set the file name according to the URL.
162 fileNameString = getFileNameFromUrl(context, urlString, null);
165 // Return the formatted file size and name as a string array.
166 return new String[] {formattedFileSize, fileNameString};
169 // `onPostExecute()` operates on the UI thread.
171 protected void onPostExecute(String[] fileStringArray) {
172 // Get a handle for the activity and the fragment manager.
173 Activity activity = activityWeakReference.get();
174 FragmentManager fragmentManager = fragmentManagerWeakReference.get();
176 // Abort if the activity is gone.
177 if (activity == null || activity.isFinishing()) {
182 // Instantiate the save dialog.
183 DialogFragment saveDialogFragment = SaveWebpageDialog.saveWebpage(saveType, urlString, fileStringArray[0], fileStringArray[1], userAgent, cookiesEnabled);
185 // Show the save dialog. It must be named `save_dialog` so that the file picker can update the file name.
186 saveDialogFragment.show(fragmentManager, activity.getString(R.string.save_dialog));
189 // Content dispositions can contain other text besides the file name, and they can be in any order.
190 // Elements are separated by semicolons. Sometimes the file names are contained in quotes.
191 public static String getFileNameFromHeaders(Context context, String contentDispositionString, String contentTypeString, String urlString) {
192 // Define a file name string.
193 String fileNameString;
195 // Only process the content disposition string if it isn't null.
196 if (contentDispositionString != null) { // The content disposition is not null.
197 // Check to see if the content disposition contains a file name.
198 if (contentDispositionString.contains("filename=")) { // The content disposition contains a filename.
199 // Get the part of the content disposition after `filename=`.
200 fileNameString = contentDispositionString.substring(contentDispositionString.indexOf("filename=") + 9);
202 // Remove any `;` and anything after it. This removes any entries after the filename.
203 if (fileNameString.contains(";")) {
204 // Remove the first `;` and everything after it.
205 fileNameString = fileNameString.substring(0, fileNameString.indexOf(";") - 1);
208 // Remove any `"` at the beginning of the string.
209 if (fileNameString.startsWith("\"")) {
210 // Remove the first character.
211 fileNameString = fileNameString.substring(1);
214 // Remove any `"` at the end of the string.
215 if (fileNameString.endsWith("\"")) {
216 // Remove the last character.
217 fileNameString = fileNameString.substring(0, fileNameString.length() - 1);
219 } else { // The headers contain no useful information.
220 // Get the file name string from the URL.
221 fileNameString = getFileNameFromUrl(context, urlString, contentTypeString);
223 } else { // The content disposition is null.
224 // Get the file name string from the URL.
225 fileNameString = getFileNameFromUrl(context, urlString, contentTypeString);
228 // Return the file name string.
229 return fileNameString;
232 private static String getFileNameFromUrl(Context context, String urlString, String contentTypeString) {
233 // Convert the URL string to a URI.
234 Uri uri = Uri.parse(urlString);
236 // Get the last path segment.
237 String lastPathSegment = uri.getLastPathSegment();
239 // Use a default file name if the last path segment is null.
240 if (lastPathSegment == null) {
241 lastPathSegment = context.getString(R.string.file);
243 if (MimeTypeMap.getSingleton().hasMimeType(contentTypeString)) { // The content type contains a MIME type.
244 // Add the file extension that matches the MIME type.
245 lastPathSegment = lastPathSegment + "." + MimeTypeMap.getSingleton().getExtensionFromMimeType(contentTypeString);
249 // Return the last path segment as the file name.
250 return lastPathSegment;