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[Sone.git] / src / main / java / net / pterodactylus / sone / text / SoneTextParser.java
1 /*
2  * Sone - FreenetLinkParser.java - Copyright © 2010 David Roden
3  *
4  * This program is free software: you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation, either version 3 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17
18 package net.pterodactylus.sone.text;
19
20 import java.io.BufferedReader;
21 import java.io.IOException;
22 import java.io.Reader;
23 import java.net.MalformedURLException;
24 import java.util.logging.Level;
25 import java.util.logging.Logger;
26 import java.util.regex.Matcher;
27 import java.util.regex.Pattern;
28
29 import net.pterodactylus.sone.core.PostProvider;
30 import net.pterodactylus.sone.core.SoneProvider;
31 import net.pterodactylus.sone.data.Post;
32 import net.pterodactylus.sone.data.Sone;
33 import net.pterodactylus.util.logging.Logging;
34 import freenet.keys.FreenetURI;
35
36 /**
37  * {@link Parser} implementation that can recognize Freenet URIs.
38  *
39  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
40  */
41 public class SoneTextParser implements Parser<SoneTextParserContext> {
42
43         /** The logger. */
44         private static final Logger logger = Logging.getLogger(SoneTextParser.class);
45
46         /** Pattern to detect whitespace. */
47         private static final Pattern whitespacePattern = Pattern.compile("[\\u000a\u0020\u00a0\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u200b\u200c\u200d\u202f\u205f\u2060\u2800\u3000]");
48
49         /**
50          * Enumeration for all recognized link types.
51          *
52          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
53          */
54         private enum LinkType {
55
56                 /** Link is a KSK. */
57                 KSK,
58
59                 /** Link is a CHK. */
60                 CHK,
61
62                 /** Link is an SSK. */
63                 SSK,
64
65                 /** Link is a USK. */
66                 USK,
67
68                 /** Link is HTTP. */
69                 HTTP,
70
71                 /** Link is HTTPS. */
72                 HTTPS,
73
74                 /** Link is a Sone. */
75                 SONE,
76
77                 /** Link is a post. */
78                 POST,
79
80         }
81
82         /** The Sone provider. */
83         private final SoneProvider soneProvider;
84
85         /** The post provider. */
86         private final PostProvider postProvider;
87
88         /**
89          * Creates a new freenet link parser.
90          *
91          * @param soneProvider
92          *            The Sone provider
93          * @param postProvider
94          *            The post provider
95          */
96         public SoneTextParser(SoneProvider soneProvider, PostProvider postProvider) {
97                 this.soneProvider = soneProvider;
98                 this.postProvider = postProvider;
99         }
100
101         //
102         // PART METHODS
103         //
104
105         /**
106          * {@inheritDoc}
107          */
108         @Override
109         public Iterable<Part> parse(SoneTextParserContext context, Reader source) throws IOException {
110                 PartContainer parts = new PartContainer();
111                 BufferedReader bufferedReader = (source instanceof BufferedReader) ? (BufferedReader) source : new BufferedReader(source);
112                 String line;
113                 boolean lastLineEmpty = true;
114                 int emptyLines = 0;
115                 while ((line = bufferedReader.readLine()) != null) {
116                         if (line.trim().length() == 0) {
117                                 if (lastLineEmpty) {
118                                         continue;
119                                 }
120                                 parts.add(new PlainTextPart("\n"));
121                                 ++emptyLines;
122                                 lastLineEmpty = emptyLines == 2;
123                                 continue;
124                         }
125                         emptyLines = 0;
126                         boolean lineComplete = true;
127                         while (line.length() > 0) {
128                                 int nextKsk = line.indexOf("KSK@");
129                                 int nextChk = line.indexOf("CHK@");
130                                 int nextSsk = line.indexOf("SSK@");
131                                 int nextUsk = line.indexOf("USK@");
132                                 int nextHttp = line.indexOf("http://");
133                                 int nextHttps = line.indexOf("https://");
134                                 int nextSone = line.indexOf("sone://");
135                                 int nextPost = line.indexOf("post://");
136                                 if ((nextKsk == -1) && (nextChk == -1) && (nextSsk == -1) && (nextUsk == -1) && (nextHttp == -1) && (nextHttps == -1) && (nextSone == -1) && (nextPost == -1)) {
137                                         if (lineComplete && !lastLineEmpty) {
138                                                 parts.add(new PlainTextPart("\n" + line));
139                                         } else {
140                                                 parts.add(new PlainTextPart(line));
141                                         }
142                                         break;
143                                 }
144                                 int next = Integer.MAX_VALUE;
145                                 LinkType linkType = null;
146                                 if ((nextKsk > -1) && (nextKsk < next)) {
147                                         next = nextKsk;
148                                         linkType = LinkType.KSK;
149                                 }
150                                 if ((nextChk > -1) && (nextChk < next)) {
151                                         next = nextChk;
152                                         linkType = LinkType.CHK;
153                                 }
154                                 if ((nextSsk > -1) && (nextSsk < next)) {
155                                         next = nextSsk;
156                                         linkType = LinkType.SSK;
157                                 }
158                                 if ((nextUsk > -1) && (nextUsk < next)) {
159                                         next = nextUsk;
160                                         linkType = LinkType.USK;
161                                 }
162                                 if ((nextHttp > -1) && (nextHttp < next)) {
163                                         next = nextHttp;
164                                         linkType = LinkType.HTTP;
165                                 }
166                                 if ((nextHttps > -1) && (nextHttps < next)) {
167                                         next = nextHttps;
168                                         linkType = LinkType.HTTPS;
169                                 }
170                                 if ((nextSone > -1) && (nextSone < next)) {
171                                         next = nextSone;
172                                         linkType = LinkType.SONE;
173                                 }
174                                 if ((nextPost > -1) && (nextPost < next)) {
175                                         next = nextPost;
176                                         linkType = LinkType.POST;
177                                 }
178                                 if (linkType == LinkType.SONE) {
179                                         if (next > 0) {
180                                                 parts.add(new PlainTextPart(line.substring(0, next)));
181                                         }
182                                         if (line.length() >= (next + 7 + 43)) {
183                                                 String soneId = line.substring(next + 7, next + 50);
184                                                 Sone sone = soneProvider.getSone(soneId, false);
185                                                 if (sone != null) {
186                                                         parts.add(new SonePart(sone));
187                                                 } else {
188                                                         parts.add(new PlainTextPart(line.substring(next, next + 50)));
189                                                 }
190                                                 line = line.substring(next + 50);
191                                         } else {
192                                                 parts.add(new PlainTextPart(line.substring(next)));
193                                                 line = "";
194                                         }
195                                         continue;
196                                 }
197                                 if (linkType == LinkType.POST) {
198                                         if (next > 0) {
199                                                 parts.add(new PlainTextPart(line.substring(0, next)));
200                                         }
201                                         if (line.length() >= (next + 7 + 36)) {
202                                                 String postId = line.substring(next + 7, next + 43);
203                                                 Post post = postProvider.getPost(postId, false);
204                                                 if ((post != null) && (post.getSone() != null)) {
205                                                         String postText = post.getText();
206                                                         postText = postText.substring(0, Math.min(postText.length(), 20)) + "…";
207                                                         parts.add(new PostPart(post));
208                                                 } else {
209                                                         parts.add(new PlainTextPart(line.substring(next, next + 43)));
210                                                 }
211                                                 line = line.substring(next + 43);
212                                         } else {
213                                                 parts.add(new PlainTextPart(line.substring(next)));
214                                                 line = "";
215                                         }
216                                         continue;
217                                 }
218                                 if ((next >= 8) && (line.substring(next - 8, next).equals("freenet:"))) {
219                                         next -= 8;
220                                         line = line.substring(0, next) + line.substring(next + 8);
221                                 }
222                                 Matcher matcher = whitespacePattern.matcher(line);
223                                 int nextSpace = matcher.find(next) ? matcher.start() : line.length();
224                                 if (nextSpace > (next + 4)) {
225                                         if (!lastLineEmpty && lineComplete) {
226                                                 parts.add(new PlainTextPart("\n" + line.substring(0, next)));
227                                         } else {
228                                                 if (next > 0) {
229                                                         parts.add(new PlainTextPart(line.substring(0, next)));
230                                                 }
231                                         }
232                                         String link = line.substring(next, nextSpace);
233                                         String name = link;
234                                         logger.log(Level.FINER, "Found link: %s", link);
235                                         logger.log(Level.FINEST, "Next: %d, CHK: %d, SSK: %d, USK: %d", new Object[] { next, nextChk, nextSsk, nextUsk });
236
237                                         if ((linkType == LinkType.KSK) || (linkType == LinkType.CHK) || (linkType == LinkType.SSK) || (linkType == LinkType.USK)) {
238                                                 FreenetURI uri;
239                                                 if (name.indexOf('?') > -1) {
240                                                         name = name.substring(0, name.indexOf('?'));
241                                                 }
242                                                 if (name.endsWith("/")) {
243                                                         name = name.substring(0, name.length() - 1);
244                                                 }
245                                                 try {
246                                                         uri = new FreenetURI(name);
247                                                         name = uri.lastMetaString();
248                                                         if (name == null) {
249                                                                 name = uri.getDocName();
250                                                         }
251                                                         if (name == null) {
252                                                                 name = link.substring(0, Math.min(9, link.length()));
253                                                         }
254                                                         boolean fromPostingSone = ((linkType == LinkType.SSK) || (linkType == LinkType.USK)) && (context != null) && (context.getPostingSone() != null) && link.substring(4, Math.min(link.length(), 47)).equals(context.getPostingSone().getId());
255                                                         parts.add(new FreenetLinkPart(link, name, fromPostingSone));
256                                                 } catch (MalformedURLException mue1) {
257                                                         /* not a valid link, insert as plain text. */
258                                                         parts.add(new PlainTextPart(link));
259                                                 } catch (NullPointerException npe1) {
260                                                         /* FreenetURI sometimes throws these, too. */
261                                                         parts.add(new PlainTextPart(link));
262                                                 } catch (ArrayIndexOutOfBoundsException aioobe1) {
263                                                         /* oh, and these, too. */
264                                                         parts.add(new PlainTextPart(link));
265                                                 }
266                                         } else if ((linkType == LinkType.HTTP) || (linkType == LinkType.HTTPS)) {
267                                                 name = link.substring(linkType == LinkType.HTTP ? 7 : 8);
268                                                 int firstSlash = name.indexOf('/');
269                                                 int lastSlash = name.lastIndexOf('/');
270                                                 if ((lastSlash - firstSlash) > 3) {
271                                                         name = name.substring(0, firstSlash + 1) + "…" + name.substring(lastSlash);
272                                                 }
273                                                 if (name.endsWith("/")) {
274                                                         name = name.substring(0, name.length() - 1);
275                                                 }
276                                                 if (((name.indexOf('/') > -1) && (name.indexOf('.') < name.lastIndexOf('.', name.indexOf('/'))) || ((name.indexOf('/') == -1) && (name.indexOf('.') < name.lastIndexOf('.')))) && name.startsWith("www.")) {
277                                                         name = name.substring(4);
278                                                 }
279                                                 if (name.indexOf('?') > -1) {
280                                                         name = name.substring(0, name.indexOf('?'));
281                                                 }
282                                                 parts.add(new LinkPart(link, name));
283                                         }
284                                         line = line.substring(nextSpace);
285                                 } else {
286                                         if (!lastLineEmpty && lineComplete) {
287                                                 parts.add(new PlainTextPart("\n" + line.substring(0, next + 4)));
288                                         } else {
289                                                 parts.add(new PlainTextPart(line.substring(0, next + 4)));
290                                         }
291                                         line = line.substring(next + 4);
292                                 }
293                                 lineComplete = false;
294                         }
295                         lastLineEmpty = false;
296                 }
297                 for (int partIndex = parts.size() - 1; partIndex >= 0; --partIndex) {
298                         Part part = parts.getPart(partIndex);
299                         if (!(part instanceof PlainTextPart) || !"\n".equals(((PlainTextPart) part).getText())) {
300                                 break;
301                         }
302                         parts.removePart(partIndex);
303                 }
304                 return parts;
305         }
306
307 }