2 * Copyright © 2020-2021 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.activities.MainWebViewActivity;
34 import com.stoutner.privacybrowser.definitions.PendingDialog;
35 import com.stoutner.privacybrowser.dialogs.SaveWebpageDialog;
36 import com.stoutner.privacybrowser.helpers.ProxyHelper;
38 import java.lang.ref.WeakReference;
39 import java.net.HttpURLConnection;
40 import java.net.Proxy;
42 import java.text.NumberFormat;
44 public class PrepareSaveDialog extends AsyncTask<String, Void, String[]> {
45 // Define weak references.
46 private final WeakReference<Activity> activityWeakReference;
47 private final WeakReference<Context> contextWeakReference;
48 private final WeakReference<FragmentManager> fragmentManagerWeakReference;
50 // Define the class variables.
51 private final int saveType;
52 private final String userAgent;
53 private final boolean cookiesEnabled;
54 private String urlString;
56 // The public constructor.
57 public PrepareSaveDialog(Activity activity, Context context, FragmentManager fragmentManager, int saveType, String userAgent, boolean cookiesEnabled) {
58 // Populate the weak references.
59 activityWeakReference = new WeakReference<>(activity);
60 contextWeakReference = new WeakReference<>(context);
61 fragmentManagerWeakReference = new WeakReference<>(fragmentManager);
63 // Store the class variables.
64 this.saveType = saveType;
65 this.userAgent = userAgent;
66 this.cookiesEnabled = cookiesEnabled;
70 protected String[] doInBackground(String... urlToSave) {
71 // Get a handle for the activity and context.
72 Activity activity = activityWeakReference.get();
73 Context context = contextWeakReference.get();
75 // Abort if the activity is gone.
76 if (activity == null || activity.isFinishing()) {
77 // Return a null string array.
81 // Get the URL string.
82 urlString = urlToSave[0];
84 // Define the strings.
85 String formattedFileSize;
86 String fileNameString;
88 // Populate the file size and name strings.
89 if (urlString.startsWith("data:")) { // The URL contains the entire data of an image.
90 // Remove `data:` from the beginning of the URL.
91 String urlWithoutData = urlString.substring(5);
93 // Get the URL MIME type, which end with a `;`.
94 String urlMimeType = urlWithoutData.substring(0, urlWithoutData.indexOf(";"));
96 // Get the Base64 data, which begins after a `,`.
97 String base64DataString = urlWithoutData.substring(urlWithoutData.indexOf(",") + 1);
99 // Calculate the file size of the data URL. Each Base64 character represents 6 bits.
100 formattedFileSize = NumberFormat.getInstance().format(base64DataString.length() * 3 / 4) + " " + context.getString(R.string.bytes);
102 // Set the file name according to the MIME type.
103 fileNameString = context.getString(R.string.file) + "." + MimeTypeMap.getSingleton().getExtensionFromMimeType(urlMimeType);
104 } else { // The URL refers to the location of the data.
105 // Initialize the formatted file size string.
106 formattedFileSize = context.getString(R.string.unknown_size);
108 // Because everything relating to requesting data from a webserver can throw errors, the entire section must catch exceptions.
110 // Convert the URL string to a URL.
111 URL url = new URL(urlString);
113 // Instantiate the proxy helper.
114 ProxyHelper proxyHelper = new ProxyHelper();
116 // Get the current proxy.
117 Proxy proxy = proxyHelper.getCurrentProxy(context);
119 // Open a connection to the URL. No data is actually sent at this point.
120 HttpURLConnection httpUrlConnection = (HttpURLConnection) url.openConnection(proxy);
122 // Add the user agent to the header property.
123 httpUrlConnection.setRequestProperty("User-Agent", userAgent);
125 // Add the cookies if they are enabled.
126 if (cookiesEnabled) {
127 // Get the cookies for the current domain.
128 String cookiesString = CookieManager.getInstance().getCookie(url.toString());
130 // only add the cookies if they are not null.
131 if (cookiesString != null) {
132 // Add the cookies to the header property.
133 httpUrlConnection.setRequestProperty("Cookie", cookiesString);
137 // 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.
139 // Get the status code. This initiates a network connection.
140 int responseCode = httpUrlConnection.getResponseCode();
142 // Check the response code.
143 if (responseCode >= 400) { // The response code is an error message.
144 // Set the formatted file size to indicate a bad URL.
145 formattedFileSize = context.getString(R.string.invalid_url);
147 // Set the file name according to the URL.
148 fileNameString = getFileNameFromUrl(context, urlString, null);
149 } else { // The response code is not an error message.
151 String contentLengthString = httpUrlConnection.getHeaderField("Content-Length");
152 String contentDispositionString = httpUrlConnection.getHeaderField("Content-Disposition");
153 String contentTypeString = httpUrlConnection.getContentType();
155 // Remove anything after the MIME type in the content type string.
156 if (contentTypeString.contains(";")) {
157 // Remove everything beginning with the `;`.
158 contentTypeString = contentTypeString.substring(0, contentTypeString.indexOf(";"));
161 // Only process the content length string if it isn't null.
162 if (contentLengthString != null) {
163 // Convert the content length string to a long.
164 long fileSize = Long.parseLong(contentLengthString);
166 // Format the file size.
167 formattedFileSize = NumberFormat.getInstance().format(fileSize) + " " + context.getString(R.string.bytes);
170 // Get the file name string from the content disposition.
171 fileNameString = getFileNameFromHeaders(context, contentDispositionString, contentTypeString, urlString);
174 // Disconnect the HTTP URL connection.
175 httpUrlConnection.disconnect();
177 } catch (Exception exception) {
178 // Set the formatted file size to indicate a bad URL.
179 formattedFileSize = context.getString(R.string.invalid_url);
181 // Set the file name according to the URL.
182 fileNameString = getFileNameFromUrl(context, urlString, null);
186 // Return the formatted file size and name as a string array.
187 return new String[] {formattedFileSize, fileNameString};
190 // `onPostExecute()` operates on the UI thread.
192 protected void onPostExecute(String[] fileStringArray) {
193 // Get a handle for the activity and the fragment manager.
194 Activity activity = activityWeakReference.get();
195 FragmentManager fragmentManager = fragmentManagerWeakReference.get();
197 // Abort if the activity is gone.
198 if (activity == null || activity.isFinishing()) {
203 // Instantiate the save dialog.
204 DialogFragment saveDialogFragment = SaveWebpageDialog.saveWebpage(saveType, urlString, fileStringArray[0], fileStringArray[1], userAgent, cookiesEnabled);
206 // Try to show the dialog. Sometimes the window is not active.
208 // Show the save dialog. It must be named `save_dialog` so that the file picker can update the file name.
209 saveDialogFragment.show(fragmentManager, activity.getString(R.string.save_dialog));
210 } catch (Exception exception) {
211 // Add the dialog to the pending dialog array list. It will be displayed in `onStart()`.
212 MainWebViewActivity.pendingDialogsArrayList.add(new PendingDialog(saveDialogFragment, activity.getString(R.string.save_dialog)));
216 // Content dispositions can contain other text besides the file name, and they can be in any order.
217 // Elements are separated by semicolons. Sometimes the file names are contained in quotes.
218 public static String getFileNameFromHeaders(Context context, String contentDispositionString, String contentTypeString, String urlString) {
219 // Define a file name string.
220 String fileNameString;
222 // Only process the content disposition string if it isn't null.
223 if (contentDispositionString != null) { // The content disposition is not null.
224 // Check to see if the content disposition contains a file name.
225 if (contentDispositionString.contains("filename=")) { // The content disposition contains a filename.
226 // Get the part of the content disposition after `filename=`.
227 fileNameString = contentDispositionString.substring(contentDispositionString.indexOf("filename=") + 9);
229 // Remove any `;` and anything after it. This removes any entries after the filename.
230 if (fileNameString.contains(";")) {
231 // Remove the first `;` and everything after it.
232 fileNameString = fileNameString.substring(0, fileNameString.indexOf(";") - 1);
235 // Remove any `"` at the beginning of the string.
236 if (fileNameString.startsWith("\"")) {
237 // Remove the first character.
238 fileNameString = fileNameString.substring(1);
241 // Remove any `"` at the end of the string.
242 if (fileNameString.endsWith("\"")) {
243 // Remove the last character.
244 fileNameString = fileNameString.substring(0, fileNameString.length() - 1);
246 } else { // The headers contain no useful information.
247 // Get the file name string from the URL.
248 fileNameString = getFileNameFromUrl(context, urlString, contentTypeString);
250 } else { // The content disposition is null.
251 // Get the file name string from the URL.
252 fileNameString = getFileNameFromUrl(context, urlString, contentTypeString);
255 // Return the file name string.
256 return fileNameString;
259 private static String getFileNameFromUrl(Context context, String urlString, String contentTypeString) {
260 // Convert the URL string to a URI.
261 Uri uri = Uri.parse(urlString);
263 // Get the last path segment.
264 String lastPathSegment = uri.getLastPathSegment();
266 // Use a default file name if the last path segment is null.
267 if (lastPathSegment == null) {
268 lastPathSegment = context.getString(R.string.file);
270 if (MimeTypeMap.getSingleton().hasMimeType(contentTypeString)) { // The content type contains a MIME type.
271 // Add the file extension that matches the MIME type.
272 lastPathSegment = lastPathSegment + "." + MimeTypeMap.getSingleton().getExtensionFromMimeType(contentTypeString);
276 // Return the last path segment as the file name.
277 return lastPathSegment;