/*
 * Copyright 2007 Yusuke Yamamoto
 *
 * 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 twitter4j;

import twitter4j.management.APIStatistics;
import twitter4j.management.APIStatisticsMBean;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Singleton instance of all Twitter API monitoring. Handles URL parsing and
 * "wire off" logic. We could avoid using a singleton here if Twitter objects
 * were instantiated from a factory.
 * 
 * @author Nick Dellamaggiore (nick.dellamaggiore <at> gmail.com)
 * @since Twitter4J 2.2.1
 */
public class TwitterAPIMonitor {
	// https?:\/\/[^\/]+\/([a-zA-Z_\.]*).*
	// finds the "method" part a Twitter REST API url, ignoring member-specific
	// resource names
	private static final Pattern pattern = Pattern.compile("https?:\\/\\/[^\\/]+\\/([a-zA-Z_\\.]*).*");

	private static final TwitterAPIMonitor SINGLETON = new TwitterAPIMonitor();

	private final APIStatistics STATISTICS = new APIStatistics(100);

	static {
		System.setProperty("http.keepAlive", "false");
	}

	/**
	 * Constructor
	 */
	private TwitterAPIMonitor() {
	}

	public APIStatisticsMBean getStatistics() {
		return STATISTICS;
	}

	void methodCalled(final String twitterUrl, final long elapsedTime, final boolean success) {
		final Matcher matcher = pattern.matcher(twitterUrl);
		if (matcher.matches() && matcher.groupCount() > 0) {
			final String method = matcher.group();
			STATISTICS.methodCalled(method, elapsedTime, success);
		}
	}

	public static TwitterAPIMonitor getInstance() {
		return SINGLETON;
	}
}