// MediaSnippet.java
// -----------------
// (C) by Michael Peter Christen; mc@yacy.net
// first published on http://www.anomic.de
// Frankfurt, Germany, 2005
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// 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 2 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, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package net.yacy.search.snippet;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.SortedMap;
import java.util.SortedSet;
import java.util.TreeSet;
import net.yacy.cora.document.analysis.Classification;
import net.yacy.cora.document.analysis.Classification.ContentDomain;
import net.yacy.cora.document.encoding.ASCII;
import net.yacy.cora.document.id.AnchorURL;
import net.yacy.cora.document.id.DigestURL;
import net.yacy.cora.federate.solr.FailCategory;
import net.yacy.cora.federate.yacy.CacheStrategy;
import net.yacy.cora.order.Base64Order;
import net.yacy.cora.protocol.ClientIdentification;
import net.yacy.cora.storage.HandleSet;
import net.yacy.cora.util.ByteArray;
import net.yacy.cora.util.ConcurrentLog;
import net.yacy.cora.util.NumberTools;
import net.yacy.cora.util.SpaceExceededException;
import net.yacy.document.Document;
import net.yacy.document.Parser;
import net.yacy.document.WordTokenizer;
import net.yacy.document.parser.html.ImageEntry;
import net.yacy.kelondro.index.RowHandleSet;
import net.yacy.repository.Blacklist.BlacklistType;
import net.yacy.search.Switchboard;
public class MediaSnippet implements Comparable<MediaSnippet>, Comparator<MediaSnippet> {
public ContentDomain type;
public DigestURL href, source;
public String name, attr, mime;
public long ranking;
public int width, height;
public long fileSize;
public MediaSnippet(final ContentDomain type, final DigestURL href, final String mime, final String name, final long fileSize, final String attr, final long ranking, final DigestURL source) {
this.type = type;
this.href = href;
this.mime = mime;
this.fileSize = fileSize;
this.source = source; // the web page where the media resource appeared
this.name = name;
this.attr = attr;
this.width = -1;
this.height = -1;
int p = 0;
if (attr != null && (p = attr.indexOf(" x ",0)) > 0) {
this.width = NumberTools.parseIntDecSubstring(attr, 0, p);
this.height = NumberTools.parseIntDecSubstring(attr, p + 3);
}
this.ranking = ranking; // the smaller the better! small values should be shown first
if ((this.name == null) || (this.name.isEmpty())) this.name = "_";
if ((this.attr == null) || (this.attr.isEmpty())) this.attr = "_";
}
public MediaSnippet(final ContentDomain type, final DigestURL href, final String mime, final String name, final long fileSize, final int width, final int height, final long ranking, final DigestURL source) {
this.type = type;
this.href = href;
this.mime = mime;
this.fileSize = fileSize;
this.source = source; // the web page where the media resource appeared
this.name = name;
this.attr = width + " x " + height;
this.width = width;
this.height = height;
this.ranking = ranking; // the smaller the better! small values should be shown first
if ((this.name == null) || (this.name.isEmpty())) this.name = "_";
if ((this.attr == null) || (this.attr.isEmpty())) this.attr = "_";
}
private int hashCache = Integer.MIN_VALUE; // if this is used in a compare method many times, a cache is useful
@Override
public int hashCode() {
if (this.hashCache == Integer.MIN_VALUE) {
this.hashCache = ByteArray.hashCode(this.href.hash());
}
return this.hashCache;
}
@Override
public String toString() {
return ASCII.String(this.href.hash());
}
@Override
public boolean equals(final Object obj) {
if (this == obj) return true;
if (obj == null) return false;
if (!(obj instanceof MediaSnippet)) return false;
final MediaSnippet other = (MediaSnippet) obj;
return Base64Order.enhancedCoder.equal(this.href.hash(), other.href.hash());
}
@Override
public int compareTo(final MediaSnippet o) {
return Base64Order.enhancedCoder.compare(this.href.hash(), o.href.hash());
}
@Override
public int compare(final MediaSnippet o1, final MediaSnippet o2) {
return o1.compareTo(o2);
}
public static List<MediaSnippet> retrieveMediaSnippets(final DigestURL url, final HandleSet queryhashes, final Classification.ContentDomain mediatype, final CacheStrategy cacheStrategy, final boolean reindexing) {
if (queryhashes.isEmpty()) {
ConcurrentLog.fine("snippet fetch", "no query hashes given for url " + url);
return new ArrayList<MediaSnippet>();
}
Document document;
try {
document = Document.mergeDocuments(url, null, Switchboard.getSwitchboard().loader.loadDocuments(Switchboard.getSwitchboard().loader.request(url, false, reindexing), cacheStrategy, Integer.MAX_VALUE, BlacklistType.SEARCH, ClientIdentification.yacyIntranetCrawlerAgent));
} catch (final IOException e) {
ConcurrentLog.fine("snippet fetch", "load error: " + e.getMessage());
return new ArrayList<MediaSnippet>();
} catch (final Parser.Failure e) {
ConcurrentLog.fine("snippet fetch", "parser error: " + e.getMessage());
return new ArrayList<MediaSnippet>();
}
final ArrayList<MediaSnippet> a = new ArrayList<MediaSnippet>();
if (document != null) {
if ((mediatype == ContentDomain.ALL) || (mediatype == ContentDomain.AUDIO)) a.addAll(computeMediaSnippets(url, document, queryhashes, ContentDomain.AUDIO));
if ((mediatype == ContentDomain.ALL) || (mediatype == ContentDomain.VIDEO)) a.addAll(computeMediaSnippets(url, document, queryhashes, ContentDomain.VIDEO));
if ((mediatype == ContentDomain.ALL) || (mediatype == ContentDomain.APP)) a.addAll(computeMediaSnippets(url, document, queryhashes, ContentDomain.APP));
if ((mediatype == ContentDomain.ALL) || (mediatype == ContentDomain.IMAGE)) a.addAll(computeImageSnippets(url, document, queryhashes));
}
return a;
}
public static List<MediaSnippet> computeMediaSnippets(final DigestURL source, final Document document, final HandleSet queryhashes, final ContentDomain mediatype) {
if (document == null) return new ArrayList<MediaSnippet>();
Map<AnchorURL, String> media = null;
if (mediatype == ContentDomain.AUDIO) media = document.getAudiolinks();
else if (mediatype == ContentDomain.VIDEO) media = document.getVideolinks();
else if (mediatype == ContentDomain.APP) media = document.getApplinks();
if (media == null) return null;
final Iterator<Map.Entry<AnchorURL, String>> i = media.entrySet().iterator();
Map.Entry<AnchorURL, String> entry;
AnchorURL url;
String desc;
final List<MediaSnippet> result = new ArrayList<MediaSnippet>();
while (i.hasNext()) {
entry = i.next();
url = entry.getKey();
desc = entry.getValue();
if (isUrlBlacklisted(BlacklistType.SEARCH, url)) continue;
final int ranking = removeAppearanceHashes(url.toNormalform(true), queryhashes).size() +
removeAppearanceHashes(desc, queryhashes).size();
if (ranking < 2 * queryhashes.size()) {
result.add(new MediaSnippet(mediatype, url, Classification.url2mime(url), desc, document.getTextLength(), null, ranking, source));
}
}
return result;
}
public static List<MediaSnippet> computeImageSnippets(final DigestURL source, final Document document, final HandleSet queryhashes) {
final SortedSet<ImageEntry> images = new TreeSet<ImageEntry>();
images.addAll(document.getImages().values()); // iterates images in descending size order!
// a measurement for the size of the images can be retrieved using the htmlFilterImageEntry.hashCode()
final Iterator<ImageEntry> i = images.iterator();
ImageEntry ientry;
DigestURL url;
String desc;
final List<MediaSnippet> result = new ArrayList<MediaSnippet>();
while (i.hasNext()) {
ientry = i.next();
url = ientry.url();
final String u = url.toNormalform(false);
if (isUrlBlacklisted(BlacklistType.SEARCH, url)) continue;
if (u.indexOf(".ico",0) >= 0 || u.indexOf("favicon",0) >= 0) continue;
if (ientry.height() > 0 && ientry.height() < 32) continue;
if (ientry.width() > 0 && ientry.width() < 32) continue;
desc = ientry.alt();
final int appcount = queryhashes.size() * 2 -
removeAppearanceHashes(url.toNormalform(true), queryhashes).size() -
removeAppearanceHashes(desc, queryhashes).size();
final long ranking = Long.MAX_VALUE - (ientry.height() + 1) * (ientry.width() + 1) * (appcount + 1);
result.add(new MediaSnippet(ContentDomain.IMAGE, url, Classification.url2mime(url), desc, ientry.fileSize(), ientry.width(), ientry.height(), ranking, source));
}
return result;
}
/**
* removed all word hashes that can be computed as tokens from a given sentence from a given hash set
* @param sentence
* @param queryhashes
* @return the given hash set minus the hashes from the tokenization of the given sentence
*/
private static HandleSet removeAppearanceHashes(final String sentence, final HandleSet queryhashes) {
// remove all hashes that appear in the sentence
if (sentence == null) return queryhashes;
final SortedMap<byte[], Integer> hs = WordTokenizer.hashSentence(sentence, 100);
final Iterator<byte[]> j = queryhashes.iterator();
byte[] hash;
Integer pos;
final HandleSet remaininghashes = new RowHandleSet(queryhashes.keylen(), queryhashes.comparator(), queryhashes.size());
while (j.hasNext()) {
hash = j.next();
pos = hs.get(hash);
if (pos == null) {
try {
remaininghashes.put(hash);
} catch (final SpaceExceededException e) {
ConcurrentLog.logException(e);
}
}
}
remaininghashes.optimize();
return remaininghashes;
}
/**
* Checks whether given URL is in blacklist for given blacklist type
*
* @param url
* The URL to check
* @param blacklistType
* Type of blacklist (see class Blacklist, BLACKLIST_FOO)
* @return isBlacklisted Whether the given URL is blacklisted
*/
private static boolean isUrlBlacklisted (final BlacklistType blacklistType, final DigestURL url) {
final boolean isBlacklisted = Switchboard.urlBlacklist.isListed(blacklistType, url.getHost().toLowerCase(), url.getFile());
if (isBlacklisted) {
Switchboard.getSwitchboard().crawlQueues.errorURL.push(url, 996, null, FailCategory.FINAL_LOAD_CONTEXT, "url in blacklist", -1);
ConcurrentLog.fine("snippet fetch", "MEDIA-SNIPPET Rejecting URL '" + url.toNormalform(false) + "'. URL is in blacklist.");
}
return isBlacklisted;
}
}