/*
 * 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.management;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

/**
 * Container for all InvocationStatisticsCalculators in a given API (like
 * Twitter)
 * 
 * @author Nick Dellamaggiore (nick.dellamaggiore <at> gmail.com)
 */
public class APIStatistics implements APIStatisticsMBean {
	private final InvocationStatisticsCalculator API_STATS_CALCULATOR;
	private final Map<String, InvocationStatisticsCalculator> METHOD_STATS_MAP;
	private final int HISTORY_SIZE;

	/**
	 * @param historySize the number of calls to track (for invocation time
	 *            averaging)
	 */
	public APIStatistics(final int historySize) {
		API_STATS_CALCULATOR = new InvocationStatisticsCalculator("API", historySize);
		METHOD_STATS_MAP = new HashMap<String, InvocationStatisticsCalculator>(100);
		HISTORY_SIZE = historySize;
	}

	@Override
	public long getAverageTime() {
		return API_STATS_CALCULATOR.getAverageTime();
	}

	@Override
	public long getCallCount() {
		return API_STATS_CALCULATOR.getCallCount();
	}

	@Override
	public long getErrorCount() {
		return API_STATS_CALCULATOR.getErrorCount();
	}

	@Override
	public synchronized Iterable<? extends InvocationStatistics> getInvocationStatistics() {
		return METHOD_STATS_MAP.values();
	}

	@Override
	public synchronized Map<String, String> getMethodLevelSummariesAsString() {
		final Map<String, String> summariesMap = new HashMap<String, String>();

		final Collection<InvocationStatisticsCalculator> allMethodStats = METHOD_STATS_MAP.values();
		for (final InvocationStatisticsCalculator methodStats : allMethodStats) {
			summariesMap.put(methodStats.getName(), methodStats.toString());
		}

		return summariesMap;
	}

	@Override
	public synchronized String getMethodLevelSummary(final String methodName) {
		return METHOD_STATS_MAP.get(methodName).toString();
	}

	/**
	 * APIStatisticsMBean implementation
	 */

	@Override
	public String getName() {
		return API_STATS_CALCULATOR.getName();
	}

	@Override
	public long getTotalTime() {
		return API_STATS_CALCULATOR.getTotalTime();
	}

	/**
	 * @param method the method invoked
	 * @param time the method execution time
	 */
	public synchronized void methodCalled(final String method, final long time, final boolean success) {
		getMethodStatistics(method).increment(time, success);

		// increment for entire API
		API_STATS_CALCULATOR.increment(time, success);
	}

	@Override
	public synchronized void reset() {
		API_STATS_CALCULATOR.reset();
		METHOD_STATS_MAP.clear();
	}

	private synchronized InvocationStatisticsCalculator getMethodStatistics(final String method) {
		InvocationStatisticsCalculator methodStats = METHOD_STATS_MAP.get(method);

		if (methodStats == null) {
			methodStats = new InvocationStatisticsCalculator(method, HISTORY_SIZE);
			METHOD_STATS_MAP.put(method, methodStats);
		}
		return methodStats;
	}
}