/**
 * Copyright (c) 2011, The University of Southampton and the individual contributors.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   *  Redistributions of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *   *  Redistributions in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the documentation
 *      and/or other materials provided with the distribution.
 *
 *   *  Neither the name of the University of Southampton nor the names of its
 *      contributors may be used to endorse or promote products derived from this
 *      software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.openimaj.stream.provider;

import java.io.IOException;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.openimaj.stream.provider.WikipediaEditsDataset.WikipediaEdit;
import org.openimaj.stream.provider.irc.AbstractIRCStreamDataset;
import org.openimaj.util.concurrent.ArrayBlockingDroppingQueue;
import org.openimaj.util.concurrent.BlockingDroppingQueue;

/**
 * Streaming dataset based on the Wikipedia/Wikimedia edits published in
 * real-time on the wikimedia IRC channels.
 * 
 * @author Sina Samangooei (ss@ecs.soton.ac.uk)
 * @author Jonathon Hare (jsh2@ecs.soton.ac.uk)
 * 
 */
public class WikipediaEditsDataset extends AbstractIRCStreamDataset<WikipediaEdit> {
        private static final String RCPMTPA_REGEX = "" +
                        "\\x0314\\[\\[\\x0307(.+?)\\x0314\\]\\]" +
                        "\\x034 (.*?)" +
                        "\\x0310.*" +
                        "\\x0302(.*?)" +
                        "\\x03.+" +
                        "\\x0303(.+?)" +
                        "\\x03.+" +
                        "\\x03 [(](.*)[)] " +
                        "\\x0310(.*)\\u0003.*";
        private static Map<String, String> languageChannels;

        static {
                languageChannels = new HashMap<String, String>();
                languageChannels.put("en", "#en.wikipedia");
        }

        private static Pattern regex = Pattern.compile(RCPMTPA_REGEX);

        /**
         * Construct the edit stream with the given buffer and language.
         * 
         * @param buffer
         *            the buffer
         * @param language
         *            the language id; currently only English "en" is supported
         * @throws IOException
         *             if there is a problem connecting
         */
        public WikipediaEditsDataset(BlockingDroppingQueue<WikipediaEdit> buffer, String language)
                        throws IOException
        {
                super(buffer, "irc.wikimedia.org", languageChannels.get(language));
        }

        /**
         * Construct the edit stream with an {@link ArrayBlockingDroppingQueue} of
         * capacity 1.
         * 
         * @param lang
         *            the language id; currently only English "en" is supported
         * @throws IOException
         *             if there is a problem connecting
         */
        public WikipediaEditsDataset(String lang) throws IOException {
                this(new ArrayBlockingDroppingQueue<WikipediaEdit>(1), lang);
        }

        /**
         * An edit
         * 
         * @author Sina Samangooei (ss@ecs.soton.ac.uk)
         * 
         */
        public static class WikipediaEdit {

                /** The change ID **/
                public int change;
                /** The user who made the change **/
                public String user;
                /** Was the edit anonymous? **/
                public boolean anon;
                /** The raw flags **/
                public String flag;
                /** Was it a robot that made the change? **/
                public boolean isRobot;
                /** Was a new page created? **/
                public boolean isNewPage;
                /** Is the edit unpatrolled? **/
                public boolean isUnpatrolled;
                /** The page that was edited **/
                public String page;
                /** The URL **/
                public URL wikipedia;
                /** The URL as a string **/
                public String wikipediaUrl;
                /** The URL of the page **/
                public URL pageUrl;
                /** The URL of the user **/
                public URL userUrl;
                /** The edit comment **/
                public String comment;

                /**
                 * Default constructor
                 * 
                 * @param message
                 *            the raw message string
                 * @throws IOException
                 *             if an error occurs during parsing
                 */
                protected WikipediaEdit(String message) throws IOException {
                        final Matcher m = regex.matcher(message);
                        if (!m.matches())
                                throw new IOException("Wikipedia message not parseable");
                        final String group1 = m.group(1);
                        final String group2 = m.group(2);
                        final String group3 = m.group(3);
                        final String group4 = m.group(4);
                        final String group5 = m.group(5).replace("+", "").replace("-", "");
                        final int neg = m.group(5).contains("-") ? -1 : 1;
                        final String group6 = m.group(6);
                        change = neg * Integer.parseInt(group5);

                        user = group4;
                        anon = Pattern.matches("\\d+.\\d+.\\d+.\\d+", user);
                        flag = group2;
                        isRobot = flag.contains("M");
                        isNewPage = flag.contains("N");
                        isUnpatrolled = flag.contains("!");
                        page = group1;
                        wikipedia = new URL(group3);
                        wikipediaUrl = "http://" + wikipedia.getHost();
                        pageUrl = new URL(wikipediaUrl + "/wiki/" + page.replace(" ", "_"));
                        if (!anon)
                                userUrl = new URL(wikipediaUrl + "/wiki/User:" + user.replace(" ", "_"));
                        else
                                userUrl = null;
                        comment = group6;
                }

                @Override
                public String toString() {
                        return String.format("User: %s, Change: %d", user, change);
                }

        }

        @Override
        public WikipediaEdit construct(String channel, String sender, String login, String hostname, String message) {
                if (!sender.equals("rc-pmtpa"))
                        return null;

                try {
                        return new WikipediaEdit(message);
                } catch (final Exception e) {
                        return null;
                }
        }
}