1/*
2 * Copyright (C) 2010 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 */
16package eu.siacs.conversations.utils;
17
18import android.content.Context;
19import android.database.Cursor;
20import android.net.Uri;
21import android.provider.OpenableColumns;
22import android.util.Log;
23
24import com.google.common.base.Strings;
25import com.google.common.collect.ImmutableList;
26
27import java.io.File;
28import java.io.FileInputStream;
29import java.io.IOException;
30import java.io.InputStream;
31import java.util.Arrays;
32import java.util.Collection;
33import java.util.HashMap;
34import java.util.List;
35import java.util.Map;
36import java.util.Properties;
37
38import eu.siacs.conversations.Config;
39import eu.siacs.conversations.entities.Transferable;
40import eu.siacs.conversations.services.ExportBackupService;
41
42/**
43 * Utilities for dealing with MIME types.
44 * Used to implement java.net.URLConnection and android.webkit.MimeTypeMap.
45 */
46public final class MimeUtils {
47
48 public static final List<String> AMBIGUOUS_CONTAINER_FORMATS = ImmutableList.of(
49 "application/ogg",
50 "video/3gpp", // .3gp files can contain audio, video or both
51 "video/3gpp2"
52 );
53
54 private static final Map<String, String> mimeTypeToExtensionMap = new HashMap<>();
55 private static final Map<String, String> extensionToMimeTypeMap = new HashMap<>();
56
57 static {
58 // The following table is based on /etc/mime.types data minus
59 // chemical/* MIME types and MIME types that don't map to any
60 // file extensions. We also exclude top-level domain names to
61 // deal with cases like:
62 //
63 // mail.google.com/a/google.com
64 //
65 // and "active" MIME types (due to potential security issues).
66 // Note that this list is _not_ in alphabetical order and must not be sorted.
67 // The "most popular" extension must come first, so that it's the one returned
68 // by guessExtensionFromMimeType.
69 add("application/andrew-inset", "ez");
70 add("application/dsptype", "tsp");
71 add("application/epub+zip", "epub");
72 add("application/gpx+xml", "gpx");
73 add("application/hta", "hta");
74 add("application/mac-binhex40", "hqx");
75 add("application/mathematica", "nb");
76 add("application/msaccess", "mdb");
77 add("application/oda", "oda");
78 add("application/ogg", "ogg");
79 add("application/pdf", "pdf");
80 add("application/pgp-keys", "key");
81 add("application/pgp-signature", "pgp");
82 add("application/pics-rules", "prf");
83 add("application/pkix-cert", "cer");
84 add("application/rar", "rar");
85 add("application/rdf+xml", "rdf");
86 add("application/rss+xml", "rss");
87 add("application/zip", "zip");
88 add("application/vnd.amazon.mobi8-ebook", "azw3");
89 add("application/vnd.amazon.mobi8-ebook", "azw");
90 add("application/vnd.amazon.mobi8-ebook", "kfx");
91 add("application/vnd.android.package-archive", "apk");
92 add("application/vnd.cinderella", "cdy");
93 add(ExportBackupService.MIME_TYPE, "ceb");
94 add("application/vnd.ms-pki.stl", "stl");
95 add("application/vnd.oasis.opendocument.database", "odb");
96 add("application/vnd.oasis.opendocument.formula", "odf");
97 add("application/vnd.oasis.opendocument.graphics", "odg");
98 add("application/vnd.oasis.opendocument.graphics-template", "otg");
99 add("application/vnd.oasis.opendocument.image", "odi");
100 add("application/vnd.oasis.opendocument.spreadsheet", "ods");
101 add("application/vnd.oasis.opendocument.spreadsheet-template", "ots");
102 add("application/vnd.oasis.opendocument.text", "odt");
103 add("application/vnd.oasis.opendocument.text-master", "odm");
104 add("application/vnd.oasis.opendocument.text-template", "ott");
105 add("application/vnd.oasis.opendocument.text-web", "oth");
106 add("application/vnd.google-earth.kml+xml", "kml");
107 add("application/vnd.google-earth.kmz", "kmz");
108 add("application/msword", "doc");
109 add("application/msword", "dot");
110 add("application/vnd.openxmlformats-officedocument.wordprocessingml.document", "docx");
111 add("application/vnd.openxmlformats-officedocument.wordprocessingml.template", "dotx");
112 add("application/vnd.ms-excel", "xls");
113 add("application/vnd.ms-excel", "xlt");
114 add("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", "xlsx");
115 add("application/vnd.openxmlformats-officedocument.spreadsheetml.template", "xltx");
116 add("application/vnd.ms-powerpoint", "ppt");
117 add("application/vnd.ms-powerpoint", "pot");
118 add("application/vnd.ms-powerpoint", "pps");
119 add("application/vnd.openxmlformats-officedocument.presentationml.presentation", "pptx");
120 add("application/vnd.openxmlformats-officedocument.presentationml.template", "potx");
121 add("application/vnd.openxmlformats-officedocument.presentationml.slideshow", "ppsx");
122 add("application/vnd.rim.cod", "cod");
123 add("application/vnd.smaf", "mmf");
124 add("application/vnd.stardivision.calc", "sdc");
125 add("application/vnd.stardivision.draw", "sda");
126 add("application/vnd.stardivision.impress", "sdd");
127 add("application/vnd.stardivision.impress", "sdp");
128 add("application/vnd.stardivision.math", "smf");
129 add("application/vnd.stardivision.writer", "sdw");
130 add("application/vnd.stardivision.writer", "vor");
131 add("application/vnd.stardivision.writer-global", "sgl");
132 add("application/vnd.sun.xml.calc", "sxc");
133 add("application/vnd.sun.xml.calc.template", "stc");
134 add("application/vnd.sun.xml.draw", "sxd");
135 add("application/vnd.sun.xml.draw.template", "std");
136 add("application/vnd.sun.xml.impress", "sxi");
137 add("application/vnd.sun.xml.impress.template", "sti");
138 add("application/vnd.sun.xml.math", "sxm");
139 add("application/vnd.sun.xml.writer", "sxw");
140 add("application/vnd.sun.xml.writer.global", "sxg");
141 add("application/vnd.sun.xml.writer.template", "stw");
142 add("application/vnd.visio", "vsd");
143 add("application/x-abiword", "abw");
144 add("application/x-apple-diskimage", "dmg");
145 add("application/x-bcpio", "bcpio");
146 add("application/x-bittorrent", "torrent");
147 add("application/x-cdf", "cdf");
148 add("application/x-cdlink", "vcd");
149 add("application/x-chess-pgn", "pgn");
150 add("application/x-cpio", "cpio");
151 add("application/x-debian-package", "deb");
152 add("application/x-debian-package", "udeb");
153 add("application/x-director", "dcr");
154 add("application/x-director", "dir");
155 add("application/x-director", "dxr");
156 add("application/x-dms", "dms");
157 add("application/x-doom", "wad");
158 add("application/x-dvi", "dvi");
159 add("application/x-font", "pfa");
160 add("application/x-font", "pfb");
161 add("application/x-font", "gsf");
162 add("application/x-font", "pcf");
163 add("application/x-font", "pcf.Z");
164 add("application/x-freemind", "mm");
165 // application/futuresplash isn't IANA, so application/x-futuresplash should come first.
166 add("application/x-futuresplash", "spl");
167 add("application/futuresplash", "spl");
168 add("application/x-gnumeric", "gnumeric");
169 add("application/x-go-sgf", "sgf");
170 add("application/x-graphing-calculator", "gcf");
171 add("application/x-gtar", "tgz");
172 add("application/x-gtar", "gtar");
173 add("application/x-gtar", "taz");
174 add("application/x-hdf", "hdf");
175 add("application/x-ica", "ica");
176 add("application/x-internet-signup", "ins");
177 add("application/x-internet-signup", "isp");
178 add("application/x-iphone", "iii");
179 add("application/x-iso9660-image", "iso");
180 add("application/x-jmol", "jmz");
181 add("application/x-kchart", "chrt");
182 add("application/x-killustrator", "kil");
183 add("application/x-koan", "skp");
184 add("application/x-koan", "skd");
185 add("application/x-koan", "skt");
186 add("application/x-koan", "skm");
187 add("application/x-kpresenter", "kpr");
188 add("application/x-kpresenter", "kpt");
189 add("application/x-kspread", "ksp");
190 add("application/x-kword", "kwd");
191 add("application/x-kword", "kwt");
192 add("application/x-latex", "latex");
193 add("application/x-lha", "lha");
194 add("application/x-lzh", "lzh");
195 add("application/x-lzx", "lzx");
196 add("application/x-maker", "frm");
197 add("application/x-maker", "maker");
198 add("application/x-maker", "frame");
199 add("application/x-maker", "fb");
200 add("application/x-maker", "book");
201 add("application/x-maker", "fbdoc");
202 add("application/x-mif", "mif");
203 add("application/x-mobipocket-ebook", "mobi");
204 add("application/x-ms-wmd", "wmd");
205 add("application/x-ms-wmz", "wmz");
206 add("application/x-msi", "msi");
207 add("application/x-ns-proxy-autoconfig", "pac");
208 add("application/x-nwc", "nwc");
209 add("application/x-object", "o");
210 add("application/x-oz-application", "oza");
211 add("application/x-pem-file", "pem");
212 add("application/x-pkcs12", "p12");
213 add("application/x-pkcs12", "pfx");
214 add("application/x-pkcs7-certreqresp", "p7r");
215 add("application/x-pkcs7-crl", "crl");
216 add("application/x-quicktimeplayer", "qtl");
217 add("application/x-shar", "shar");
218 add("application/x-shockwave-flash", "swf");
219 add("application/x-stuffit", "sit");
220 add("application/x-sv4cpio", "sv4cpio");
221 add("application/x-sv4crc", "sv4crc");
222 add("application/x-tar", "tar");
223 add("application/x-texinfo", "texinfo");
224 add("application/x-texinfo", "texi");
225 add("application/x-troff", "t");
226 add("application/x-troff", "roff");
227 add("application/x-troff-man", "man");
228 add("application/x-ustar", "ustar");
229 add("application/x-wais-source", "src");
230 add("application/x-wingz", "wz");
231 add("application/x-webarchive", "webarchive");
232 add("application/x-webarchive-xml", "webarchivexml");
233 add("application/x-x509-ca-cert", "crt");
234 add("application/x-x509-user-cert", "crt");
235 add("application/x-x509-server-cert", "crt");
236 add("application/x-xcf", "xcf");
237 add("application/x-xfig", "fig");
238 add("application/xhtml+xml", "xhtml");
239 add("video/3gpp", "3gpp");
240 add("video/3gpp", "3gp");
241 add("video/3gpp2", "3gpp2");
242 add("video/3gpp2", "3g2");
243 add("audio/3gpp", "3gpp");
244 add("audio/3gpp", "3gp");
245 add("audio/aac", "aac");
246 add("audio/aac-adts", "aac");
247 add("audio/amr", "amr");
248 add("audio/amr-wb", "awb");
249 add("audio/basic", "snd");
250 add("audio/flac", "flac");
251 add("application/x-flac", "flac");
252 add("audio/imelody", "imy");
253 add("audio/midi", "mid");
254 add("audio/midi", "midi");
255 add("audio/midi", "ota");
256 add("audio/midi", "kar");
257 add("audio/midi", "rtttl");
258 add("audio/midi", "xmf");
259 add("audio/mobile-xmf", "mxmf");
260 // add ".mp3" first so it will be the default for guessExtensionFromMimeType
261 add("audio/mpeg", "mp3");
262 add("audio/mpeg", "mpga");
263 add("audio/mpeg", "mpega");
264 add("audio/mpeg", "mp2");
265 add("audio/mp4", "m4a");
266 add("audio/x-m4b", "m4b");
267 add("audio/mpegurl", "m3u");
268 add("audio/ogg", "oga");
269 add("audio/opus", "opus");
270 add("audio/prs.sid", "sid");
271 add("audio/x-aiff", "aif");
272 add("audio/x-aiff", "aiff");
273 add("audio/x-aiff", "aifc");
274 add("audio/x-gsm", "gsm");
275 add("audio/x-matroska", "mka");
276 add("audio/x-mpegurl", "m3u");
277 add("audio/x-ms-wma", "wma");
278 add("audio/x-ms-wax", "wax");
279 add("audio/x-pn-realaudio", "ra");
280 add("audio/x-pn-realaudio", "rm");
281 add("audio/x-pn-realaudio", "ram");
282 add("audio/x-realaudio", "ra");
283 add("audio/x-scpls", "pls");
284 add("audio/x-sd2", "sd2");
285 add("audio/x-wav", "wav");
286 // image/bmp isn't IANA, so image/x-ms-bmp should come first.
287 add("image/x-ms-bmp", "bmp");
288 add("image/bmp", "bmp");
289 add("image/gif", "gif");
290 // image/ico isn't IANA, so image/x-icon should come first.
291 add("image/x-icon", "ico");
292 add("image/ico", "cur");
293 add("image/ico", "ico");
294 add("image/ief", "ief");
295 add("image/heic", "heic");
296 add("image/heif", "heif");
297 add("image/avif", "avif");
298 // add ".jpg" first so it will be the default for guessExtensionFromMimeType
299 add("image/jpeg", "jpg");
300 add("image/jpeg", "jpeg");
301 add("image/jpeg", "jpe");
302 add("image/jpeg", "jfif");
303 add("image/jpeg", "jif");
304 add("image/pcx", "pcx");
305 add("image/png", "png");
306 add("image/svg+xml", "svg");
307 add("image/svg+xml", "svgz");
308 add("image/tiff", "tiff");
309 add("image/tiff", "tif");
310 add("image/vnd.djvu", "djvu");
311 add("image/vnd.djvu", "djv");
312 add("image/vnd.wap.wbmp", "wbmp");
313 add("image/webp", "webp");
314 add("image/x-cmu-raster", "ras");
315 add("image/x-coreldraw", "cdr");
316 add("image/x-coreldrawpattern", "pat");
317 add("image/x-coreldrawtemplate", "cdt");
318 add("image/x-corelphotopaint", "cpt");
319 add("image/x-jg", "art");
320 add("image/x-jng", "jng");
321 add("image/x-photoshop", "psd");
322 add("image/x-portable-anymap", "pnm");
323 add("image/x-portable-bitmap", "pbm");
324 add("image/x-portable-graymap", "pgm");
325 add("image/x-portable-pixmap", "ppm");
326 add("image/x-rgb", "rgb");
327 add("image/x-xbitmap", "xbm");
328 add("image/x-xpixmap", "xpm");
329 add("image/x-xwindowdump", "xwd");
330 add("model/iges", "igs");
331 add("model/iges", "iges");
332 add("model/mesh", "msh");
333 add("model/mesh", "mesh");
334 add("model/mesh", "silo");
335 add("text/calendar", "ics");
336 add("text/calendar", "icz");
337 add("text/comma-separated-values", "csv");
338 add("text/css", "css");
339 add("text/html", "htm");
340 add("text/html", "html");
341 add("text/h323", "323");
342 add("text/iuls", "uls");
343 add("text/mathml", "mml");
344 // add ".txt" first so it will be the default for guessExtensionFromMimeType
345 add("text/plain", "txt");
346 add("text/plain", "asc");
347 add("text/plain", "text");
348 add("text/plain", "diff");
349 add("text/plain", "po"); // reserve "pot" for vnd.ms-powerpoint
350 add("text/richtext", "rtx");
351 add("text/rtf", "rtf");
352 add("text/text", "phps");
353 add("text/tab-separated-values", "tsv");
354 add("text/xml", "xml");
355 add("text/x-bibtex", "bib");
356 add("text/x-boo", "boo");
357 add("text/x-c++hdr", "hpp");
358 add("text/x-c++hdr", "h++");
359 add("text/x-c++hdr", "hxx");
360 add("text/x-c++hdr", "hh");
361 add("text/x-c++src", "cpp");
362 add("text/x-c++src", "c++");
363 add("text/x-c++src", "cc");
364 add("text/x-c++src", "cxx");
365 add("text/x-chdr", "h");
366 add("text/x-component", "htc");
367 add("text/x-csh", "csh");
368 add("text/x-csrc", "c");
369 add("text/x-dsrc", "d");
370 add("text/x-haskell", "hs");
371 add("text/x-java", "java");
372 add("text/x-literate-haskell", "lhs");
373 add("text/x-moc", "moc");
374 add("text/x-pascal", "p");
375 add("text/x-pascal", "pas");
376 add("text/x-pcs-gcd", "gcd");
377 add("text/x-setext", "etx");
378 add("text/x-tcl", "tcl");
379 add("text/x-tex", "tex");
380 add("text/x-tex", "ltx");
381 add("text/x-tex", "sty");
382 add("text/x-tex", "cls");
383 add("text/x-vcalendar", "vcs");
384 add("text/x-vcard", "vcf");
385 add("video/avi", "avi");
386 add("video/dl", "dl");
387 add("video/dv", "dif");
388 add("video/dv", "dv");
389 add("video/fli", "fli");
390 add("video/m4v", "m4v");
391 add("video/mp2ts", "ts");
392 add("video/ogg", "ogv");
393 add("video/mpeg", "mpeg");
394 add("video/mpeg", "mpg");
395 add("video/mpeg", "mpe");
396 add("video/mp4", "mp4");
397 add("video/mpeg", "VOB");
398 add("video/quicktime", "qt");
399 add("video/quicktime", "mov");
400 add("video/vnd.mpegurl", "mxu");
401 add("video/webm", "webm");
402 add("video/x-la-asf", "lsf");
403 add("video/x-la-asf", "lsx");
404 add("video/x-matroska", "mkv");
405 add("video/x-mng", "mng");
406 add("video/x-ms-asf", "asf");
407 add("video/x-ms-asf", "asx");
408 add("video/x-ms-wm", "wm");
409 add("video/x-ms-wmv", "wmv");
410 add("video/x-ms-wmx", "wmx");
411 add("video/x-ms-wvx", "wvx");
412 add("video/x-sgi-movie", "movie");
413 add("video/x-webex", "wrf");
414 add("x-conference/x-cooltalk", "ice");
415 add("x-epoc/x-sisx-app", "sisx");
416 applyOverrides();
417 }
418
419 // mime types that are more reliant by path
420 private static final Collection<String> PATH_PRECEDENCE_MIME_TYPE = Arrays.asList("audio/x-m4b");
421
422 private static void add(String mimeType, String extension) {
423 // If we have an existing x -> y mapping, we do not want to
424 // override it with another mapping x -> y2.
425 // If a mime type maps to several extensions
426 // the first extension added is considered the most popular
427 // so we do not want to overwrite it later.
428 if (!mimeTypeToExtensionMap.containsKey(mimeType)) {
429 mimeTypeToExtensionMap.put(mimeType, extension);
430 }
431 if (!extensionToMimeTypeMap.containsKey(extension)) {
432 extensionToMimeTypeMap.put(extension, mimeType);
433 }
434 }
435
436 private static InputStream getContentTypesPropertiesStream() {
437 // User override?
438 String userTable = System.getProperty("content.types.user.table");
439 if (userTable != null) {
440 File f = new File(userTable);
441 if (f.exists()) {
442 try {
443 return new FileInputStream(f);
444 } catch (IOException ignored) {
445 }
446 }
447 }
448 // Standard location?
449 File f = new File(System.getProperty("java.home"), "lib" + File.separator + "content-types.properties");
450 if (f.exists()) {
451 try {
452 return new FileInputStream(f);
453 } catch (IOException ignored) {
454 }
455 }
456 return null;
457 }
458
459 /**
460 * This isn't what the RI does. The RI doesn't have hard-coded defaults, so supplying your
461 * own "content.types.user.table" means you don't get any of the built-ins, and the built-ins
462 * come from "$JAVA_HOME/lib/content-types.properties".
463 */
464 private static void applyOverrides() {
465 // Get the appropriate InputStream to read overrides from, if any.
466 InputStream stream = getContentTypesPropertiesStream();
467 if (stream == null) {
468 return;
469 }
470 try {
471 try {
472 // Read the properties file...
473 Properties overrides = new Properties();
474 overrides.load(stream);
475 // And translate its mapping to ours...
476 for (Map.Entry<Object, Object> entry : overrides.entrySet()) {
477 String extension = (String) entry.getKey();
478 String mimeType = (String) entry.getValue();
479 add(mimeType, extension);
480 }
481 } finally {
482 stream.close();
483 }
484 } catch (IOException ignored) {
485 }
486 }
487
488 private MimeUtils() {
489 }
490
491 /**
492 * Returns true if the given MIME type has an entry in the map.
493 *
494 * @param mimeType A MIME type (i.e. text/plain)
495 * @return True iff there is a mimeType entry in the map.
496 */
497 public static boolean hasMimeType(String mimeType) {
498 if (mimeType == null || mimeType.isEmpty()) {
499 return false;
500 }
501 return mimeTypeToExtensionMap.containsKey(mimeType);
502 }
503
504 /**
505 * Returns the MIME type for the given extension.
506 *
507 * @param extension A file extension without the leading '.'
508 * @return The MIME type for the given extension or null iff there is none.
509 */
510 public static String guessMimeTypeFromExtension(String extension) {
511 if (extension == null || extension.isEmpty()) {
512 return null;
513 }
514 return extensionToMimeTypeMap.get(extension.toLowerCase());
515 }
516
517 /**
518 * Returns true if the given extension has a registered MIME type.
519 *
520 * @param extension A file extension without the leading '.'
521 * @return True iff there is an extension entry in the map.
522 */
523 public static boolean hasExtension(String extension) {
524 if (extension == null || extension.isEmpty()) {
525 return false;
526 }
527 return extensionToMimeTypeMap.containsKey(extension);
528 }
529
530 /**
531 * Returns the registered extension for the given MIME type. Note that some
532 * MIME types map to multiple extensions. This call will return the most
533 * common extension for the given MIME type.
534 *
535 * @param mimeType A MIME type (i.e. text/plain)
536 * @return The extension for the given MIME type or null iff there is none.
537 */
538 public static String guessExtensionFromMimeType(String mimeType) {
539 if (mimeType == null || mimeType.isEmpty()) {
540 return null;
541 }
542 return mimeTypeToExtensionMap.get(mimeType.split(";")[0]);
543 }
544
545 public static String guessMimeTypeFromUriAndMime(final Context context, final Uri uri, final String mime) {
546 Log.d(Config.LOGTAG, "guessMimeTypeFromUriAndMime(" + uri + "," + mime+")");
547 final String mimeFromUri = guessMimeTypeFromUri(context, uri);
548 Log.d(Config.LOGTAG,"mimeFromUri:"+mimeFromUri);
549 if (PATH_PRECEDENCE_MIME_TYPE.contains(mimeFromUri)) {
550 return mimeFromUri;
551 } else if (mime == null || mime.equals("application/octet-stream")) {
552 return mimeFromUri;
553 } else {
554 return mime;
555 }
556 }
557
558 public static String guessMimeTypeFromUri(final Context context, final Uri uri) {
559 final String mimeTypeContentResolver = guessFromContentResolver(context, uri);
560 final String mimeTypeFromQueryParameter = uri.getQueryParameter("mimeType");
561 final String name = "content".equals(uri.getScheme()) ? getDisplayName(context, uri) : null;
562 final String mimeTypeFromName = Strings.isNullOrEmpty(name) ? null : guessFromPath(name);
563 final String path = uri.getPath();
564 final String mimeTypeFromPath = Strings.isNullOrEmpty(path) ? null : guessFromPath(path);
565 if (PATH_PRECEDENCE_MIME_TYPE.contains(mimeTypeFromName)) {
566 return mimeTypeFromName;
567 }
568 if (PATH_PRECEDENCE_MIME_TYPE.contains(mimeTypeFromPath)) {
569 return mimeTypeFromPath;
570 }
571 if (mimeTypeContentResolver != null && !"application/octet-stream".equals(mimeTypeContentResolver)) {
572 return mimeTypeContentResolver;
573 }
574 if (mimeTypeFromName != null) {
575 return mimeTypeFromName;
576 }
577 if (mimeTypeFromQueryParameter != null) {
578 return mimeTypeFromQueryParameter;
579 }
580 return mimeTypeFromPath;
581 }
582
583 private static String guessFromContentResolver(final Context context, final Uri uri) {
584 try {
585 return context.getContentResolver().getType(uri);
586 } catch (final Throwable e) {
587 return null;
588 }
589 }
590
591 private static String getDisplayName(final Context context, final Uri uri) {
592 try (final Cursor cursor = context.getContentResolver().query(uri, null, null, null, null)) {
593 if (cursor != null && cursor.moveToFirst()) {
594 final int index = cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
595 if (index == -1) {
596 return null;
597 }
598 return cursor.getString(index);
599 }
600 } catch (final Exception e) {
601 return null;
602 }
603 return null;
604 }
605
606 private static String guessFromPath(final String path) {
607 final int start = path.lastIndexOf('.') + 1;
608 if (start < path.length()) {
609 return MimeUtils.guessMimeTypeFromExtension(path.substring(start));
610 }
611 return null;
612 }
613
614 public static String extractRelevantExtension(final String path) {
615 return extractRelevantExtension(path, false);
616 }
617
618 public static String extractRelevantExtension(final String path, final boolean ignoreCryptoExtension) {
619 if (Strings.isNullOrEmpty(path)) {
620 return null;
621 }
622
623 final String filenameQueryAnchor = path.substring(path.lastIndexOf('/') + 1);
624 final String filenameQuery = cutBefore(filenameQueryAnchor, '#');
625 final String filename = cutBefore(filenameQuery, '?');
626 final int dotPosition = filename.lastIndexOf('.');
627
628 if (dotPosition == -1) {
629 return null;
630 }
631 final String extension = filename.substring(dotPosition + 1);
632 // we want the real file extension, not the crypto one
633 if (ignoreCryptoExtension && Transferable.VALID_CRYPTO_EXTENSIONS.contains(extension)) {
634 return extractRelevantExtension(filename.substring(0, dotPosition));
635 } else {
636 return extension;
637 }
638 }
639
640 private static String cutBefore(final String input, final char c) {
641 final int position = input.indexOf(c);
642 if (position > 0) {
643 return input.substring(0, position);
644 } else {
645 return input;
646 }
647 }
648}