/*
 * Copyright (c) 2010-2015, b3log.org
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.b3log.solo.event.ping;


import java.net.URL;
import java.net.URLEncoder;
import org.b3log.latke.Latkes;
import org.b3log.latke.event.AbstractEventListener;
import org.b3log.latke.event.Event;
import org.b3log.latke.event.EventException;
import org.b3log.latke.ioc.LatkeBeanManager;
import org.b3log.latke.ioc.Lifecycle;
import org.b3log.latke.logging.Level;
import org.b3log.latke.logging.Logger;
import org.b3log.latke.urlfetch.HTTPRequest;
import org.b3log.latke.urlfetch.URLFetchService;
import org.b3log.latke.urlfetch.URLFetchServiceFactory;
import org.b3log.solo.event.EventTypes;
import org.b3log.solo.model.Article;
import org.b3log.solo.model.Preference;
import org.b3log.solo.service.PreferenceQueryService;
import org.json.JSONObject;


/**
 * This listener is responsible for pinging <a href="http://blogsearch.google.com">
 * Google Blog Search Service</a> asynchronously while updating an article.
 *
 * <p>
 *   <li>
 *     <a href="http://www.google.com/help/blogsearch/pinging_API.html">
 *     About Google Blog Search Pinging Service API</a>
 *   </li>
 * </p>
 *
 * @author <a href="http://88250.b3log.org">Liang Ding</a>
 * @version 1.0.0.3, May 17, 2013
 * @see AddArticleGoogleBlogSearchPinger
 * @since 0.3.1
 */
public final class UpdateArticleGoogleBlogSearchPinger extends AbstractEventListener<JSONObject> {

    /**
     * Logger.
     */
    private static final Logger LOGGER = Logger.getLogger(UpdateArticleGoogleBlogSearchPinger.class.getName());

    /**
     * URL fetch service.
     */
    private static final URLFetchService URL_FETCH_SERVICE = URLFetchServiceFactory.getURLFetchService();

    /**
     * Gets the event type {@linkplain EventTypes#UPDATE_ARTICLE}.
     *
     * @return event type
     */
    @Override
    public String getEventType() {
        return EventTypes.UPDATE_ARTICLE;
    }

    @Override
    public void action(final Event<JSONObject> event) throws EventException {
        final JSONObject eventData = event.getData();

        String articleTitle = null;

        final LatkeBeanManager beanManager = Lifecycle.getBeanManager();
        final PreferenceQueryService preferenceQueryService = beanManager.getReference(PreferenceQueryService.class);

        try {
            final JSONObject article = eventData.getJSONObject(Article.ARTICLE);

            articleTitle = article.getString(Article.ARTICLE_TITLE);
            final JSONObject preference = preferenceQueryService.getPreference();
            final String blogTitle = preference.getString(Preference.BLOG_TITLE);

            if (Latkes.getServePath().contains("localhost")) {
                LOGGER.log(Level.INFO,
                    "Blog Solo runs on local server, so should not ping " + "Google Blog Search Service for the article[title={0}]",
                    new Object[] {article.getString(Article.ARTICLE_TITLE)});
                return;
            }

            final String articlePermalink = Latkes.getServePath() + article.getString(Article.ARTICLE_PERMALINK);
            final String spec = "http://blogsearch.google.com/ping?name=" + URLEncoder.encode(blogTitle, "UTF-8") + "&url="
                + URLEncoder.encode(Latkes.getServePath(), "UTF-8") + "&changesURL=" + URLEncoder.encode(articlePermalink, "UTF-8");

            LOGGER.log(Level.DEBUG,
                "Request Google Blog Search Service API[{0}] while updateing " + "an article[title=" + articleTitle + "]", spec);
            final HTTPRequest request = new HTTPRequest();

            request.setURL(new URL(spec));
            URL_FETCH_SERVICE.fetchAsync(request);
        } catch (final Exception e) {
            LOGGER.log(Level.ERROR, "Ping Google Blog Search Service fail while updating an " + "article[title=" + articleTitle + "]", e);
        }
    }
}
