src/main/java/net/pterodactylus/sone/text/SoneTextParser.java

   1 /*
   2  * Sone - FreenetLinkParser.java - Copyright © 2010–2012 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.sone.database.memory.MemorySone;
  34 import net.pterodactylus.util.logging.Logging;
  35 import freenet.keys.FreenetURI;
  36
  37 /**
  38  * {@link Parser} implementation that can recognize Freenet URIs.
  39  *
  40  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  41  */
  42 public class SoneTextParser implements Parser<SoneTextParserContext> {
  43
  44         /** The logger. */
  45         private static final Logger logger = Logging.getLogger(SoneTextParser.class);
  46
  47         /** Pattern to detect whitespace. */
  48         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]");
  49
  50         /**
  51          * Enumeration for all recognized link types.
  52          *
  53          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  54          */
  55         private enum LinkType {
  56
  57                 /** Link is a KSK. */
  58                 KSK,
  59
  60                 /** Link is a CHK. */
  61                 CHK,
  62
  63                 /** Link is an SSK. */
  64                 SSK,
  65
  66                 /** Link is a USK. */
  67                 USK,
  68
  69                 /** Link is HTTP. */
  70                 HTTP,
  71
  72                 /** Link is HTTPS. */
  73                 HTTPS,
  74
  75                 /** Link is a Sone. */
  76                 SONE,
  77
  78                 /** Link is a post. */
  79                 POST,
  80
  81         }
  82
  83         /** The Sone provider. */
  84         private final SoneProvider soneProvider;
  85
  86         /** The post provider. */
  87         private final PostProvider postProvider;
  88
  89         /**
  90          * Creates a new freenet link parser.
  91          *
  92          * @param soneProvider
  93          *            The Sone provider
  94          * @param postProvider
  95          *            The post provider
  96          */
  97         public SoneTextParser(SoneProvider soneProvider, PostProvider postProvider) {
  98                 this.soneProvider = soneProvider;
  99                 this.postProvider = postProvider;
 100         }
 101
 102         //
 103         // PART METHODS
 104         //
 105
 106         /**
 107          * {@inheritDoc}
 108          */
 109         @Override
 110         public Iterable<Part> parse(SoneTextParserContext context, Reader source) throws IOException {
 111                 PartContainer parts = new PartContainer();
 112                 BufferedReader bufferedReader = (source instanceof BufferedReader) ? (BufferedReader) source : new BufferedReader(source);
 113                 String line;
 114                 boolean lastLineEmpty = true;
 115                 int emptyLines = 0;
 116                 while ((line = bufferedReader.readLine()) != null) {
 117                         if (line.trim().length() == 0) {
 118                                 if (lastLineEmpty) {
 119                                         continue;
 120                                 }
 121                                 parts.add(new PlainTextPart("\n"));
 122                                 ++emptyLines;
 123                                 lastLineEmpty = emptyLines == 2;
 124                                 continue;
 125                         }
 126                         emptyLines = 0;
 127                         /*
 128                          * lineComplete tracks whether the block you are parsing is the
 129                          * first block of the line. this is important because sometimes you
 130                          * have to add an additional line break.
 131                          */
 132                         boolean lineComplete = true;
 133                         while (line.length() > 0) {
 134                                 int nextKsk = line.indexOf("KSK@");
 135                                 int nextChk = line.indexOf("CHK@");
 136                                 int nextSsk = line.indexOf("SSK@");
 137                                 int nextUsk = line.indexOf("USK@");
 138                                 int nextHttp = line.indexOf("http://");
 139                                 int nextHttps = line.indexOf("https://");
 140                                 int nextSone = line.indexOf("sone://");
 141                                 int nextPost = line.indexOf("post://");
 142                                 if ((nextKsk == -1) && (nextChk == -1) && (nextSsk == -1) && (nextUsk == -1) && (nextHttp == -1) && (nextHttps == -1) && (nextSone == -1) && (nextPost == -1)) {
 143                                         if (lineComplete && !lastLineEmpty) {
 144                                                 parts.add(new PlainTextPart("\n" + line));
 145                                         } else {
 146                                                 parts.add(new PlainTextPart(line));
 147                                         }
 148                                         break;
 149                                 }
 150                                 int next = Integer.MAX_VALUE;
 151                                 LinkType linkType = null;
 152                                 if ((nextKsk > -1) && (nextKsk < next)) {
 153                                         next = nextKsk;
 154                                         linkType = LinkType.KSK;
 155                                 }
 156                                 if ((nextChk > -1) && (nextChk < next)) {
 157                                         next = nextChk;
 158                                         linkType = LinkType.CHK;
 159                                 }
 160                                 if ((nextSsk > -1) && (nextSsk < next)) {
 161                                         next = nextSsk;
 162                                         linkType = LinkType.SSK;
 163                                 }
 164                                 if ((nextUsk > -1) && (nextUsk < next)) {
 165                                         next = nextUsk;
 166                                         linkType = LinkType.USK;
 167                                 }
 168                                 if ((nextHttp > -1) && (nextHttp < next)) {
 169                                         next = nextHttp;
 170                                         linkType = LinkType.HTTP;
 171                                 }
 172                                 if ((nextHttps > -1) && (nextHttps < next)) {
 173                                         next = nextHttps;
 174                                         linkType = LinkType.HTTPS;
 175                                 }
 176                                 if ((nextSone > -1) && (nextSone < next)) {
 177                                         next = nextSone;
 178                                         linkType = LinkType.SONE;
 179                                 }
 180                                 if ((nextPost > -1) && (nextPost < next)) {
 181                                         next = nextPost;
 182                                         linkType = LinkType.POST;
 183                                 }
 184
 185                                 /* cut off “freenet:” from before keys. */
 186                                 if (((linkType == LinkType.KSK) || (linkType == LinkType.CHK) || (linkType == LinkType.SSK) || (linkType == LinkType.USK)) && (next >= 8) && (line.substring(next - 8, next).equals("freenet:"))) {
 187                                         next -= 8;
 188                                         line = line.substring(0, next) + line.substring(next + 8);
 189                                 }
 190
 191                                 /* if there is text before the next item, write it out. */
 192                                 if (lineComplete && !lastLineEmpty) {
 193                                         parts.add(new PlainTextPart("\n"));
 194                                 }
 195                                 if (next > 0) {
 196                                         parts.add(new PlainTextPart(line.substring(0, next)));
 197                                         line = line.substring(next);
 198                                         next = 0;
 199                                 }
 200                                 lineComplete = false;
 201
 202                                 if (linkType == LinkType.SONE) {
 203                                         if (line.length() >= (7 + 43)) {
 204                                                 String soneId = line.substring(7, 50);
 205                                                 Sone sone = soneProvider.getSone(soneId, false);
 206                                                 if (sone == null) {
 207                                                         /*
 208                                                          * don’t use create=true above, we don’t want the
 209                                                          * empty shell.
 210                                                          */
 211                                                         sone = new MemorySone(soneId, false);
 212                                                 }
 213                                                 parts.add(new SonePart(sone));
 214                                                 line = line.substring(50);
 215                                         } else {
 216                                                 parts.add(new PlainTextPart(line));
 217                                                 line = "";
 218                                         }
 219                                         continue;
 220                                 }
 221                                 if (linkType == LinkType.POST) {
 222                                         if (line.length() >= (7 + 36)) {
 223                                                 String postId = line.substring(7, 43);
 224                                                 Post post = postProvider.getPost(postId, false);
 225                                                 if ((post != null) && (post.getSone() != null)) {
 226                                                         parts.add(new PostPart(post));
 227                                                 } else {
 228                                                         parts.add(new PlainTextPart(line.substring(0, 43)));
 229                                                 }
 230                                                 line = line.substring(43);
 231                                         } else {
 232                                                 parts.add(new PlainTextPart(line));
 233                                                 line = "";
 234                                         }
 235                                         continue;
 236                                 }
 237                                 Matcher matcher = whitespacePattern.matcher(line);
 238                                 int nextSpace = matcher.find(0) ? matcher.start() : line.length();
 239                                 String link = line.substring(0, nextSpace);
 240                                 String name = link;
 241                                 logger.log(Level.FINER, String.format("Found link: %s", link));
 242                                 logger.log(Level.FINEST, String.format("CHK: %d, SSK: %d, USK: %d", nextChk, nextSsk, nextUsk));
 243
 244                                 if ((linkType == LinkType.KSK) || (linkType == LinkType.CHK) || (linkType == LinkType.SSK) || (linkType == LinkType.USK)) {
 245                                         FreenetURI uri;
 246                                         if (name.indexOf('?') > -1) {
 247                                                 name = name.substring(0, name.indexOf('?'));
 248                                         }
 249                                         if (name.endsWith("/")) {
 250                                                 name = name.substring(0, name.length() - 1);
 251                                         }
 252                                         try {
 253                                                 uri = new FreenetURI(name);
 254                                                 name = uri.lastMetaString();
 255                                                 if (name == null) {
 256                                                         name = uri.getDocName();
 257                                                 }
 258                                                 if (name == null) {
 259                                                         name = link.substring(0, Math.min(9, link.length()));
 260                                                 }
 261                                                 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());
 262                                                 parts.add(new FreenetLinkPart(link, name, fromPostingSone));
 263                                         } catch (MalformedURLException mue1) {
 264                                                 /* not a valid link, insert as plain text. */
 265                                                 parts.add(new PlainTextPart(link));
 266                                         } catch (NullPointerException npe1) {
 267                                                 /* FreenetURI sometimes throws these, too. */
 268                                                 parts.add(new PlainTextPart(link));
 269                                         } catch (ArrayIndexOutOfBoundsException aioobe1) {
 270                                                 /* oh, and these, too. */
 271                                                 parts.add(new PlainTextPart(link));
 272                                         }
 273                                 } else if ((linkType == LinkType.HTTP) || (linkType == LinkType.HTTPS)) {
 274                                         name = link.substring(linkType == LinkType.HTTP ? 7 : 8);
 275                                         int firstSlash = name.indexOf('/');
 276                                         int lastSlash = name.lastIndexOf('/');
 277                                         if ((lastSlash - firstSlash) > 3) {
 278                                                 name = name.substring(0, firstSlash + 1) + "…" + name.substring(lastSlash);
 279                                         }
 280                                         if (name.endsWith("/")) {
 281                                                 name = name.substring(0, name.length() - 1);
 282                                         }
 283                                         if (((name.indexOf('/') > -1) && (name.indexOf('.') < name.lastIndexOf('.', name.indexOf('/'))) || ((name.indexOf('/') == -1) && (name.indexOf('.') < name.lastIndexOf('.')))) && name.startsWith("www.")) {
 284                                                 name = name.substring(4);
 285                                         }
 286                                         if (name.indexOf('?') > -1) {
 287                                                 name = name.substring(0, name.indexOf('?'));
 288                                         }
 289                                         parts.add(new LinkPart(link, name));
 290                                 }
 291                                 line = line.substring(nextSpace);
 292                         }
 293                         lastLineEmpty = false;
 294                 }
 295                 for (int partIndex = parts.size() - 1; partIndex >= 0; --partIndex) {
 296                         Part part = parts.getPart(partIndex);
 297                         if (!(part instanceof PlainTextPart) || !"\n".equals(((PlainTextPart) part).getText())) {
 298                                 break;
 299                         }
 300                         parts.removePart(partIndex);
 301                 }
 302                 return parts;
 303         }
 304
 305 }