Add album builder creation to memory database.
[Sone.git] / src / main / java / net / pterodactylus / sone / text / SoneTextParser.java
1 /*
2  * Sone - SoneTextParser.java - Copyright © 2010–2013 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.data.Post;
30 import net.pterodactylus.sone.data.Sone;
31 import net.pterodactylus.sone.database.PostProvider;
32 import net.pterodactylus.sone.database.SoneProvider;
33 import net.pterodactylus.util.io.Closer;
34 import net.pterodactylus.util.logging.Logging;
35
36 import com.google.common.base.Optional;
37
38 import freenet.keys.FreenetURI;
39
40 /**
41  * {@link Parser} implementation that can recognize Freenet URIs.
42  *
43  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
44  */
45 public class SoneTextParser implements Parser<SoneTextParserContext> {
46
47         /** The logger. */
48         private static final Logger logger = Logging.getLogger(SoneTextParser.class);
49
50         /** Pattern to detect whitespace. */
51         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]");
52
53         /**
54          * Enumeration for all recognized link types.
55          *
56          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
57          */
58         private enum LinkType {
59
60                 /** Link is a KSK. */
61                 KSK("KSK@"),
62
63                 /** Link is a CHK. */
64                 CHK("CHK@"),
65
66                 /** Link is an SSK. */
67                 SSK("SSK@"),
68
69                 /** Link is a USK. */
70                 USK("USK@"),
71
72                 /** Link is HTTP. */
73                 HTTP("http://"),
74
75                 /** Link is HTTPS. */
76                 HTTPS("https://"),
77
78                 /** Link is a Sone. */
79                 SONE("sone://"),
80
81                 /** Link is a post. */
82                 POST("post://");
83
84                 /** The scheme identifying this link type. */
85                 private final String scheme;
86
87                 /**
88                  * Creates a new link type identified by the given scheme.
89                  *
90                  * @param scheme
91                  *            The scheme of the link type
92                  */
93                 private LinkType(String scheme) {
94                         this.scheme = scheme;
95                 }
96
97                 /**
98                  * Returns the scheme of this link type.
99                  *
100                  * @return The scheme of this link type
101                  */
102                 public String getScheme() {
103                         return scheme;
104                 }
105
106         }
107
108         /** The Sone provider. */
109         private final SoneProvider soneProvider;
110
111         /** The post provider. */
112         private final PostProvider postProvider;
113
114         /**
115          * Creates a new freenet link parser.
116          *
117          * @param soneProvider
118          *            The Sone provider
119          * @param postProvider
120          *            The post provider
121          */
122         public SoneTextParser(SoneProvider soneProvider, PostProvider postProvider) {
123                 this.soneProvider = soneProvider;
124                 this.postProvider = postProvider;
125         }
126
127         //
128         // PART METHODS
129         //
130
131         /**
132          * {@inheritDoc}
133          */
134         @Override
135         public Iterable<Part> parse(SoneTextParserContext context, Reader source) throws IOException {
136                 PartContainer parts = new PartContainer();
137                 BufferedReader bufferedReader = (source instanceof BufferedReader) ? (BufferedReader) source : new BufferedReader(source);
138                 try {
139                         String line;
140                         boolean lastLineEmpty = true;
141                         int emptyLines = 0;
142                         while ((line = bufferedReader.readLine()) != null) {
143                                 if (line.trim().length() == 0) {
144                                         if (lastLineEmpty) {
145                                                 continue;
146                                         }
147                                         parts.add(new PlainTextPart("\n"));
148                                         ++emptyLines;
149                                         lastLineEmpty = emptyLines == 2;
150                                         continue;
151                                 }
152                                 emptyLines = 0;
153                                 /*
154                                  * lineComplete tracks whether the block you are parsing is the
155                                  * first block of the line. this is important because sometimes
156                                  * you have to add an additional line break.
157                                  */
158                                 boolean lineComplete = true;
159                                 while (line.length() > 0) {
160                                         int nextKsk = line.indexOf("KSK@");
161                                         int nextChk = line.indexOf("CHK@");
162                                         int nextSsk = line.indexOf("SSK@");
163                                         int nextUsk = line.indexOf("USK@");
164                                         int nextHttp = line.indexOf("http://");
165                                         int nextHttps = line.indexOf("https://");
166                                         int nextSone = line.indexOf("sone://");
167                                         int nextPost = line.indexOf("post://");
168                                         if ((nextKsk == -1) && (nextChk == -1) && (nextSsk == -1) && (nextUsk == -1) && (nextHttp == -1) && (nextHttps == -1) && (nextSone == -1) && (nextPost == -1)) {
169                                                 if (lineComplete && !lastLineEmpty) {
170                                                         parts.add(new PlainTextPart("\n" + line));
171                                                 } else {
172                                                         parts.add(new PlainTextPart(line));
173                                                 }
174                                                 break;
175                                         }
176                                         int next = Integer.MAX_VALUE;
177                                         LinkType linkType = null;
178                                         if ((nextKsk > -1) && (nextKsk < next)) {
179                                                 next = nextKsk;
180                                                 linkType = LinkType.KSK;
181                                         }
182                                         if ((nextChk > -1) && (nextChk < next)) {
183                                                 next = nextChk;
184                                                 linkType = LinkType.CHK;
185                                         }
186                                         if ((nextSsk > -1) && (nextSsk < next)) {
187                                                 next = nextSsk;
188                                                 linkType = LinkType.SSK;
189                                         }
190                                         if ((nextUsk > -1) && (nextUsk < next)) {
191                                                 next = nextUsk;
192                                                 linkType = LinkType.USK;
193                                         }
194                                         if ((nextHttp > -1) && (nextHttp < next)) {
195                                                 next = nextHttp;
196                                                 linkType = LinkType.HTTP;
197                                         }
198                                         if ((nextHttps > -1) && (nextHttps < next)) {
199                                                 next = nextHttps;
200                                                 linkType = LinkType.HTTPS;
201                                         }
202                                         if ((nextSone > -1) && (nextSone < next)) {
203                                                 next = nextSone;
204                                                 linkType = LinkType.SONE;
205                                         }
206                                         if ((nextPost > -1) && (nextPost < next)) {
207                                                 next = nextPost;
208                                                 linkType = LinkType.POST;
209                                         }
210
211                                         /* cut off “freenet:” from before keys. */
212                                         if (((linkType == LinkType.KSK) || (linkType == LinkType.CHK) || (linkType == LinkType.SSK) || (linkType == LinkType.USK)) && (next >= 8) && (line.substring(next - 8, next).equals("freenet:"))) {
213                                                 next -= 8;
214                                                 line = line.substring(0, next) + line.substring(next + 8);
215                                         }
216
217                                         /* if there is text before the next item, write it out. */
218                                         if (lineComplete && !lastLineEmpty) {
219                                                 parts.add(new PlainTextPart("\n"));
220                                         }
221                                         if (next > 0) {
222                                                 parts.add(new PlainTextPart(line.substring(0, next)));
223                                                 line = line.substring(next);
224                                                 next = 0;
225                                         }
226                                         lineComplete = false;
227
228                                         Matcher matcher = whitespacePattern.matcher(line);
229                                         int nextSpace = matcher.find(0) ? matcher.start() : line.length();
230                                         String link = line.substring(0, nextSpace);
231                                         String name = link;
232                                         logger.log(Level.FINER, String.format("Found link: %s", link));
233                                         logger.log(Level.FINEST, String.format("CHK: %d, SSK: %d, USK: %d", nextChk, nextSsk, nextUsk));
234
235                                         /* if there is no text after the scheme, it’s not a link! */
236                                         if (link.equals(linkType.getScheme())) {
237                                                 parts.add(new PlainTextPart(linkType.getScheme()));
238                                                 line = line.substring(linkType.getScheme().length());
239                                                 continue;
240                                         }
241
242                                         if (linkType == LinkType.SONE) {
243                                                 if (line.length() >= (7 + 43)) {
244                                                         String soneId = line.substring(7, 50);
245                                                         Optional<Sone> sone = soneProvider.getSone(soneId);
246                                                         if (!sone.isPresent()) {
247                                                                 /*
248                                                                  * don’t use create=true above, we don’t want
249                                                                  * the empty shell.
250                                                                  */
251                                                                 sone = Optional.fromNullable(new Sone(soneId, false));
252                                                         }
253                                                         parts.add(new SonePart(sone.get()));
254                                                         line = line.substring(50);
255                                                 } else {
256                                                         parts.add(new PlainTextPart(line));
257                                                         line = "";
258                                                 }
259                                                 continue;
260                                         }
261                                         if (linkType == LinkType.POST) {
262                                                 if (line.length() >= (7 + 36)) {
263                                                         String postId = line.substring(7, 43);
264                                                         Optional<Post> post = postProvider.getPost(postId);
265                                                         if (post.isPresent()) {
266                                                                 parts.add(new PostPart(post.get()));
267                                                         } else {
268                                                                 parts.add(new PlainTextPart(line.substring(0, 43)));
269                                                         }
270                                                         line = line.substring(43);
271                                                 } else {
272                                                         parts.add(new PlainTextPart(line));
273                                                         line = "";
274                                                 }
275                                                 continue;
276                                         }
277
278                                         if ((linkType == LinkType.KSK) || (linkType == LinkType.CHK) || (linkType == LinkType.SSK) || (linkType == LinkType.USK)) {
279                                                 FreenetURI uri;
280                                                 if (name.indexOf('?') > -1) {
281                                                         name = name.substring(0, name.indexOf('?'));
282                                                 }
283                                                 if (name.endsWith("/")) {
284                                                         name = name.substring(0, name.length() - 1);
285                                                 }
286                                                 try {
287                                                         uri = new FreenetURI(name);
288                                                         name = uri.lastMetaString();
289                                                         if (name == null) {
290                                                                 name = uri.getDocName();
291                                                         }
292                                                         if (name == null) {
293                                                                 name = link.substring(0, Math.min(9, link.length()));
294                                                         }
295                                                         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());
296                                                         parts.add(new FreenetLinkPart(link, name, fromPostingSone));
297                                                 } catch (MalformedURLException mue1) {
298                                                         /* not a valid link, insert as plain text. */
299                                                         parts.add(new PlainTextPart(link));
300                                                 } catch (NullPointerException npe1) {
301                                                         /* FreenetURI sometimes throws these, too. */
302                                                         parts.add(new PlainTextPart(link));
303                                                 } catch (ArrayIndexOutOfBoundsException aioobe1) {
304                                                         /* oh, and these, too. */
305                                                         parts.add(new PlainTextPart(link));
306                                                 }
307                                         } else if ((linkType == LinkType.HTTP) || (linkType == LinkType.HTTPS)) {
308                                                 name = link.substring(linkType == LinkType.HTTP ? 7 : 8);
309                                                 int firstSlash = name.indexOf('/');
310                                                 int lastSlash = name.lastIndexOf('/');
311                                                 if ((lastSlash - firstSlash) > 3) {
312                                                         name = name.substring(0, firstSlash + 1) + "…" + name.substring(lastSlash);
313                                                 }
314                                                 if (name.endsWith("/")) {
315                                                         name = name.substring(0, name.length() - 1);
316                                                 }
317                                                 if (((name.indexOf('/') > -1) && (name.indexOf('.') < name.lastIndexOf('.', name.indexOf('/'))) || ((name.indexOf('/') == -1) && (name.indexOf('.') < name.lastIndexOf('.')))) && name.startsWith("www.")) {
318                                                         name = name.substring(4);
319                                                 }
320                                                 if (name.indexOf('?') > -1) {
321                                                         name = name.substring(0, name.indexOf('?'));
322                                                 }
323                                                 parts.add(new LinkPart(link, name));
324                                         }
325                                         line = line.substring(nextSpace);
326                                 }
327                                 lastLineEmpty = false;
328                         }
329                 } finally {
330                         if (bufferedReader != source) {
331                                 Closer.close(bufferedReader);
332                         }
333                 }
334                 for (int partIndex = parts.size() - 1; partIndex >= 0; --partIndex) {
335                         Part part = parts.getPart(partIndex);
336                         if (!(part instanceof PlainTextPart) || !"\n".equals(((PlainTextPart) part).getText())) {
337                                 break;
338                         }
339                         parts.removePart(partIndex);
340                 }
341                 return parts;
342         }
343
344 }