/*
* Sone - SoneTextParser.java - Copyright © 2010–2013 David Roden
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package net.pterodactylus.sone.text;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.Reader;
import java.net.MalformedURLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import net.pterodactylus.sone.data.Post;
import net.pterodactylus.sone.data.Sone;
import net.pterodactylus.sone.data.SoneImpl;
import net.pterodactylus.sone.database.PostProvider;
import net.pterodactylus.sone.database.SoneProvider;
import net.pterodactylus.util.io.Closer;
import net.pterodactylus.util.logging.Logging;
import com.google.common.base.Optional;
import freenet.keys.FreenetURI;
/**
* {@link Parser} implementation that can recognize Freenet URIs.
*
* @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
*/
public class SoneTextParser implements Parser<SoneTextParserContext> {
/** The logger. */
private static final Logger logger = Logging.getLogger(SoneTextParser.class);
/** Pattern to detect whitespace. */
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]");
/**
* Enumeration for all recognized link types.
*
* @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
*/
private enum LinkType {
/** Link is a KSK. */
KSK("KSK@"),
/** Link is a CHK. */
CHK("CHK@"),
/** Link is an SSK. */
SSK("SSK@"),
/** Link is a USK. */
USK("USK@"),
/** Link is HTTP. */
HTTP("http://"),
/** Link is HTTPS. */
HTTPS("https://"),
/** Link is a Sone. */
SONE("sone://"),
/** Link is a post. */
POST("post://");
/** The scheme identifying this link type. */
private final String scheme;
/**
* Creates a new link type identified by the given scheme.
*
* @param scheme
* The scheme of the link type
*/
private LinkType(String scheme) {
this.scheme = scheme;
}
/**
* Returns the scheme of this link type.
*
* @return The scheme of this link type
*/
public String getScheme() {
return scheme;
}
}
/** The Sone provider. */
private final SoneProvider soneProvider;
/** The post provider. */
private final PostProvider postProvider;
/**
* Creates a new freenet link parser.
*
* @param soneProvider
* The Sone provider
* @param postProvider
* The post provider
*/
public SoneTextParser(SoneProvider soneProvider, PostProvider postProvider) {
this.soneProvider = soneProvider;
this.postProvider = postProvider;
}
//
// PART METHODS
//
/**
* {@inheritDoc}
*/
@Override
public Iterable<Part> parse(SoneTextParserContext context, Reader source) throws IOException {
PartContainer parts = new PartContainer();
BufferedReader bufferedReader = (source instanceof BufferedReader) ? (BufferedReader) source : new BufferedReader(source);
try {
String line;
boolean lastLineEmpty = true;
int emptyLines = 0;
while ((line = bufferedReader.readLine()) != null) {
if (line.trim().length() == 0) {
if (lastLineEmpty) {
continue;
}
parts.add(new PlainTextPart("\n"));
++emptyLines;
lastLineEmpty = emptyLines == 2;
continue;
}
emptyLines = 0;
/*
* lineComplete tracks whether the block you are parsing is the
* first block of the line. this is important because sometimes
* you have to add an additional line break.
*/
boolean lineComplete = true;
while (line.length() > 0) {
int nextKsk = line.indexOf("KSK@");
int nextChk = line.indexOf("CHK@");
int nextSsk = line.indexOf("SSK@");
int nextUsk = line.indexOf("USK@");
int nextHttp = line.indexOf("http://");
int nextHttps = line.indexOf("https://");
int nextSone = line.indexOf("sone://");
int nextPost = line.indexOf("post://");
if ((nextKsk == -1) && (nextChk == -1) && (nextSsk == -1) && (nextUsk == -1) && (nextHttp == -1) && (nextHttps == -1) && (nextSone == -1) && (nextPost == -1)) {
if (lineComplete && !lastLineEmpty) {
parts.add(new PlainTextPart("\n" + line));
} else {
parts.add(new PlainTextPart(line));
}
break;
}
int next = Integer.MAX_VALUE;
LinkType linkType = null;
if ((nextKsk > -1) && (nextKsk < next)) {
next = nextKsk;
linkType = LinkType.KSK;
}
if ((nextChk > -1) && (nextChk < next)) {
next = nextChk;
linkType = LinkType.CHK;
}
if ((nextSsk > -1) && (nextSsk < next)) {
next = nextSsk;
linkType = LinkType.SSK;
}
if ((nextUsk > -1) && (nextUsk < next)) {
next = nextUsk;
linkType = LinkType.USK;
}
if ((nextHttp > -1) && (nextHttp < next)) {
next = nextHttp;
linkType = LinkType.HTTP;
}
if ((nextHttps > -1) && (nextHttps < next)) {
next = nextHttps;
linkType = LinkType.HTTPS;
}
if ((nextSone > -1) && (nextSone < next)) {
next = nextSone;
linkType = LinkType.SONE;
}
if ((nextPost > -1) && (nextPost < next)) {
next = nextPost;
linkType = LinkType.POST;
}
/* cut off “freenet:” from before keys. */
if (((linkType == LinkType.KSK) || (linkType == LinkType.CHK) || (linkType == LinkType.SSK) || (linkType == LinkType.USK)) && (next >= 8) && (line.substring(next - 8, next).equals("freenet:"))) {
next -= 8;
line = line.substring(0, next) + line.substring(next + 8);
}
/* if there is text before the next item, write it out. */
if (lineComplete && !lastLineEmpty) {
parts.add(new PlainTextPart("\n"));
}
if (next > 0) {
parts.add(new PlainTextPart(line.substring(0, next)));
line = line.substring(next);
next = 0;
}
lineComplete = false;
Matcher matcher = whitespacePattern.matcher(line);
int nextSpace = matcher.find(0) ? matcher.start() : line.length();
String link = line.substring(0, nextSpace);
String name = link;
logger.log(Level.FINER, String.format("Found link: %s", link));
logger.log(Level.FINEST, String.format("CHK: %d, SSK: %d, USK: %d", nextChk, nextSsk, nextUsk));
/* if there is no text after the scheme, it’s not a link! */
if (link.equals(linkType.getScheme())) {
parts.add(new PlainTextPart(linkType.getScheme()));
line = line.substring(linkType.getScheme().length());
continue;
}
if (linkType == LinkType.SONE) {
if (line.length() >= (7 + 43)) {
String soneId = line.substring(7, 50);
Optional<Sone> sone = soneProvider.getSone(soneId);
if (!sone.isPresent()) {
/*
* don’t use create=true above, we don’t want
* the empty shell.
*/
sone = Optional.<Sone>of(new SoneImpl(soneId, false));
}
parts.add(new SonePart(sone.get()));
line = line.substring(50);
} else {
parts.add(new PlainTextPart(line));
line = "";
}
continue;
}
if (linkType == LinkType.POST) {
if (line.length() >= (7 + 36)) {
String postId = line.substring(7, 43);
Optional<Post> post = postProvider.getPost(postId);
if (post.isPresent()) {
parts.add(new PostPart(post.get()));
} else {
parts.add(new PlainTextPart(line.substring(0, 43)));
}
line = line.substring(43);
} else {
parts.add(new PlainTextPart(line));
line = "";
}
continue;
}
if ((linkType == LinkType.KSK) || (linkType == LinkType.CHK) || (linkType == LinkType.SSK) || (linkType == LinkType.USK)) {
FreenetURI uri;
if (name.indexOf('?') > -1) {
name = name.substring(0, name.indexOf('?'));
}
if (name.endsWith("/")) {
name = name.substring(0, name.length() - 1);
}
try {
uri = new FreenetURI(name);
name = uri.lastMetaString();
if (name == null) {
name = uri.getDocName();
}
if (name == null) {
name = link.substring(0, Math.min(9, link.length()));
}
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());
parts.add(new FreenetLinkPart(link, name, fromPostingSone));
} catch (MalformedURLException mue1) {
/* not a valid link, insert as plain text. */
parts.add(new PlainTextPart(link));
} catch (NullPointerException npe1) {
/* FreenetURI sometimes throws these, too. */
parts.add(new PlainTextPart(link));
} catch (ArrayIndexOutOfBoundsException aioobe1) {
/* oh, and these, too. */
parts.add(new PlainTextPart(link));
}
} else if ((linkType == LinkType.HTTP) || (linkType == LinkType.HTTPS)) {
name = link.substring(linkType == LinkType.HTTP ? 7 : 8);
int firstSlash = name.indexOf('/');
int lastSlash = name.lastIndexOf('/');
if ((lastSlash - firstSlash) > 3) {
name = name.substring(0, firstSlash + 1) + "…" + name.substring(lastSlash);
}
if (name.endsWith("/")) {
name = name.substring(0, name.length() - 1);
}
if (((name.indexOf('/') > -1) && (name.indexOf('.') < name.lastIndexOf('.', name.indexOf('/'))) || ((name.indexOf('/') == -1) && (name.indexOf('.') < name.lastIndexOf('.')))) && name.startsWith("www.")) {
name = name.substring(4);
}
if (name.indexOf('?') > -1) {
name = name.substring(0, name.indexOf('?'));
}
parts.add(new LinkPart(link, name));
}
line = line.substring(nextSpace);
}
lastLineEmpty = false;
}
} finally {
if (bufferedReader != source) {
Closer.close(bufferedReader);
}
}
for (int partIndex = parts.size() - 1; partIndex >= 0; --partIndex) {
Part part = parts.getPart(partIndex);
if (!(part instanceof PlainTextPart) || !"\n".equals(((PlainTextPart) part).getText())) {
break;
}
parts.removePart(partIndex);
}
return parts;
}
}