// MediaSnippet.java
// -----------------
// (C) by Michael Peter Christen; mc@yacy.net
// first published on http://www.anomic.de
// Frankfurt, Germany, 2005
//
// $LastChangedDate: 2011-06-13 23:44:03 +0200 (Mo, 13. Jun 2011) $
// $LastChangedRevision: 7778 $
// $LastChangedBy: orbiter $
//
// 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 de.anomic.search;
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.ASCII;
import net.yacy.cora.document.MultiProtocolURI;
import net.yacy.cora.services.federated.yacy.CacheStrategy;
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.data.meta.DigestURI;
import net.yacy.kelondro.index.HandleSet;
import net.yacy.kelondro.index.RowSpaceExceededException;
import net.yacy.kelondro.logging.Log;
import net.yacy.kelondro.order.Base64Order;
import net.yacy.kelondro.util.ByteArray;
import de.anomic.data.MimeTable;
public class MediaSnippet implements Comparable<MediaSnippet>, Comparator<MediaSnippet> {
public ContentDomain type;
public DigestURI href, source;
public String name, attr, mime;
public long ranking;
public int width, height;
public long fileSize;
public MediaSnippet(final ContentDomain type, final DigestURI href, final String mime, final String name, final long fileSize, final String attr, final long ranking, final DigestURI 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) {
this.width = Integer.parseInt(attr.substring(0, p).trim());
this.height = Integer.parseInt(attr.substring(p + 3).trim());
}
this.ranking = ranking; // the smaller the better! small values should be shown first
if ((this.name == null) || (this.name.length() == 0)) this.name = "_";
if ((this.attr == null) || (this.attr.length() == 0)) this.attr = "_";
}
public MediaSnippet(final ContentDomain type, final DigestURI href, final String mime, final String name, final long fileSize, final int width, final int height, final long ranking, final DigestURI 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.length() == 0)) this.name = "_";
if ((this.attr == null) || (this.attr.length() == 0)) this.attr = "_";
}
@Override
public int hashCode() {
return ByteArray.hashCode(this.href.hash());
}
@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());
}
public int compareTo(final MediaSnippet o) {
return Base64Order.enhancedCoder.compare(this.href.hash(), o.href.hash());
}
public int compare(final MediaSnippet o1, final MediaSnippet o2) {
return o1.compareTo(o2);
}
public static List<MediaSnippet> retrieveMediaSnippets(final DigestURI url, final HandleSet queryhashes, final ContentDomain mediatype, final CacheStrategy cacheStrategy, final int timeout, final boolean reindexing) {
if (queryhashes.isEmpty()) {
Log.logFine("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, timeout, Long.MAX_VALUE));
} catch (final IOException e) {
Log.logFine("snippet fetch", "load error: " + e.getMessage());
return new ArrayList<MediaSnippet>();
} catch (final Parser.Failure e) {
Log.logFine("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 DigestURI source, final Document document, final HandleSet queryhashes, final ContentDomain mediatype) {
if (document == null) return new ArrayList<MediaSnippet>();
Map<MultiProtocolURI, 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<MultiProtocolURI, String>> i = media.entrySet().iterator();
Map.Entry<MultiProtocolURI, String> entry;
DigestURI url;
String desc;
final List<MediaSnippet> result = new ArrayList<MediaSnippet>();
while (i.hasNext()) {
entry = i.next();
url = new DigestURI(entry.getKey());
desc = entry.getValue();
final int ranking = removeAppearanceHashes(url.toNormalform(false, false), queryhashes).size() +
removeAppearanceHashes(desc, queryhashes).size();
if (ranking < 2 * queryhashes.size()) {
result.add(new MediaSnippet(mediatype, url, MimeTable.url2mime(url), desc, document.getTextLength(), null, ranking, source));
}
}
return result;
}
public static List<MediaSnippet> computeImageSnippets(final DigestURI 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;
DigestURI url;
String desc;
final List<MediaSnippet> result = new ArrayList<MediaSnippet>();
while (i.hasNext()) {
ientry = i.next();
url = new DigestURI(ientry.url());
final String u = url.toString();
if (u.indexOf(".ico") >= 0 || u.indexOf("favicon") >= 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(false, false), 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, MimeTable.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, null);
final Iterator<byte[]> j = queryhashes.iterator();
byte[] hash;
Integer pos;
final HandleSet remaininghashes = new HandleSet(queryhashes.row().primaryKeyLength, queryhashes.comparator(), queryhashes.size());
while (j.hasNext()) {
hash = j.next();
pos = hs.get(hash);
if (pos == null) {
try {
remaininghashes.put(hash);
} catch (final RowSpaceExceededException e) {
Log.logException(e);
}
}
}
return remaininghashes;
}
}