// transferURL.java
// -----------------------
// part of the AnomicHTTPD caching proxy
// (C) by Michael Peter Christen; mc@anomic.de
// first published on http://www.anomic.de
// Frankfurt, Germany, 2004, 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
//
// Using this software in any meaning (reading, learning, copying, compiling,
// running) means that you agree that the Author(s) is (are) not responsible
// for cost, loss of data or any harm that may be caused directly or indirectly
// by usage of this softare or this documentation. The usage of this software
// is on your own risk. The installation and usage (starting/running) of this
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// software which must be done by the user of the software; the author(s) is
// (are) also not responsible for proper configuration and usage of the
// software, even if provoked by documentation provided together with
// the software.
//
// Any changes to this file according to the GPL as documented in the file
// gpl.txt aside this file in the shipment you received can be done to the
// lines that follows this copyright notice here, but changes must not be
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// Contributions and changes to the program code must be marked as such.

// You must compile this file with
// javac -classpath .:../classes transferRWI.java

import java.io.IOException;

import de.anomic.http.httpHeader;
import de.anomic.plasma.plasmaCrawlLURLEntry;
import de.anomic.plasma.plasmaSwitchboard;
import de.anomic.plasma.urlPattern.plasmaURLPattern;
import de.anomic.server.serverCore;
import de.anomic.server.serverObjects;
import de.anomic.server.serverSwitch;
import de.anomic.yacy.yacyCore;
import de.anomic.yacy.yacySeed;

public final class transferURL {

    public static serverObjects respond(httpHeader header, serverObjects post, serverSwitch ss) throws InterruptedException {
        if (post == null || ss == null) { return null; }

        long start = System.currentTimeMillis();

        // return variable that accumulates replacements
        final plasmaSwitchboard sb = (plasmaSwitchboard) ss;
        final serverObjects prop = new serverObjects();
        if (prop == null || sb == null) { return null; }

        // request values
        final String iam      = post.get("iam", "");      // seed hash of requester
//      final String youare   = post.get("youare", "");   // seed hash of the target peer, needed for network stability
//      final String key      = post.get("key", "");      // transmission key
        final int urlc        = post.getInt("urlc", 0);    // number of transported urls
        final boolean granted = sb.getConfig("allowReceiveIndex", "false").equals("true");
        final boolean blockBlacklist = sb.getConfig("indexReceiveBlockBlacklist", "false").equals("true");

        // response values
        String result = "";
        String doublevalues = "0";

        final yacySeed otherPeer = yacyCore.seedDB.get(iam);
        final String otherPeerName = iam + ":" + ((otherPeer == null) ? "NULL" : (otherPeer.getName() + "/" + otherPeer.getVersion()));

        if (granted) {
            int received = 0;
            int blocked = 0;
            final int sizeBefore = sb.urlPool.loadedURL.size();
            // read the urls from the other properties and store
            String urls;
            plasmaCrawlLURLEntry lEntry;
            for (int i = 0; i < urlc; i++) {
                serverCore.checkInterruption();
                urls = (String) post.get("url" + i);
                if (urls == null) {
                    yacyCore.log.logFine("transferURL: got null URL-string from peer " + otherPeerName);
                } else {
                    lEntry = sb.urlPool.loadedURL.newEntry(urls);
                    if (lEntry == null) {
                        yacyCore.log.logWarning("transferURL: received invalid URL (entry null) from peer " + otherPeerName + "\n\tURL Property: " + urls);
                        // TODO: should we send back an error message???
                    } else {
                        plasmaCrawlLURLEntry.Components comp = lEntry.comp();
                        if (comp.url() == null) {
                            yacyCore.log.logWarning("transferURL: received invalid URL (url null) from peer " + otherPeerName + "\n\tURL Property: " + urls);
                            // TODO: should we send back an error message???
                        } else {
                            if ((blockBlacklist) && (plasmaSwitchboard.urlBlacklist.isListed(plasmaURLPattern.BLACKLIST_DHT, lEntry.hash(), comp.url()))) {
                                int deleted = sb.wordIndex.tryRemoveURLs(lEntry.hash());
                                yacyCore.log.logFine("transferURL: blocked blacklisted URL '" + comp.url().toNormalform() + "' from peer " + otherPeerName + "; deleted " + deleted + " URL entries from RWIs");
                                lEntry = null;
                                blocked++;
                            } else try {
                                sb.urlPool.loadedURL.store(lEntry);
                                sb.urlPool.loadedURL.stack(lEntry, iam, iam, 3);
                                yacyCore.log.logFine("transferURL: received URL '" + comp.url().toNormalform() + "' from peer " + otherPeerName);
                                received++;
                            } catch (IOException e) {
                                    e.printStackTrace();
                            }
                        }
                    }
                }
            }

            yacyCore.seedDB.mySeed.incRU(received);

            // return rewrite properties
            final int more = sb.urlPool.loadedURL.size() - sizeBefore;
            doublevalues = Integer.toString(received - more);
            sb.getLog().logInfo("Received " + received + " URLs from peer " + otherPeerName + " in " + (System.currentTimeMillis() - start) + " ms, Blocked " + blocked + " URLs");
            if ((received - more) > 0) sb.getLog().logSevere("Received " + doublevalues + " double URLs from peer " + otherPeerName);
            result = "ok";
        } else {
            sb.getLog().logInfo("Rejecting URLs from peer " + otherPeerName + ". Not granted.");
            result = "error_not_granted";
        }

        prop.put("double", doublevalues);
        prop.put("result", result);
        return prop;
    }
}