/*
 * Created on May 29, 2004
 *
 */
package net.sourceforge.fenixedu.tools;

import java.util.Calendar;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

/**
 * @author Luis Cruz
 * 
 */
public class Profiler {

    private static Profiler profiler = null;

    private static Map startTimes = null;

    private static Map times = null;

    private static int keyIndex = 0;

    private static int[] objectSynchCreateInstance = new int[0];

    private static void init() {
	synchronized (objectSynchCreateInstance) {
	    if (profiler == null) {
		profiler = new Profiler();
	    }
	    if (startTimes == null) {
		startTimes = new HashMap();
	    }
	    if (times == null) {
		times = new HashMap();
	    }
	}
    }

    public static Profiler getInstance() {
	init();
	return profiler;
    }

    public static void resetInstance() {
	startTimes = null;
	times = null;
	init();
    }

    private Profiler() {
	super();
    }

    public static int getKeyIndex() {
	synchronized (objectSynchCreateInstance) {
	    return keyIndex++;
	}
    }

    public static Object start(String key) {
	HashKey hashKey = profiler.getHashKey(key, getKeyIndex());
	startTimes.put(hashKey, Calendar.getInstance());
	return hashKey;
    }

    public static void stop(Object hashKey) {
	Calendar stopTime = Calendar.getInstance();
	Calendar startTime = (Calendar) startTimes.get(hashKey);
	Long executionTime = Long.valueOf(stopTime.getTimeInMillis() - startTime.getTimeInMillis());
	times.put(hashKey, executionTime);
    }

    public static void report() {
	Map resultTimes = new HashMap();

	long totalTime = 0;
	Iterator iterator = times.keySet().iterator();
	while (iterator.hasNext()) {
	    HashKey hashKey = (HashKey) iterator.next();
	    Long time = (Long) times.get(hashKey);
	    totalTime += time.longValue();

	    String originalKey = hashKey.getKey();
	    Long resultTime = (Long) resultTimes.get(originalKey);
	    if (resultTime == null) {
		resultTimes.put(originalKey, time);
	    } else {
		resultTimes.remove(originalKey);
		resultTimes.put(originalKey, Long.valueOf(resultTime.longValue() + time.longValue()));
	    }
	}

	iterator = resultTimes.keySet().iterator();
	while (iterator.hasNext()) {
	    String originalKey = (String) iterator.next();
	    System.out.println(originalKey + " " + resultTimes.get(originalKey));
	}
	System.out.println("Total time: " + totalTime + "ms");
    }

    public HashKey getHashKey(String key, int index) {
	return new HashKey(key, index);
    }

    public class HashKey {

	private String key = null;

	private int index = 0;

	public HashKey(String keyArg, int indexArg) {
	    key = keyArg;
	    index = indexArg;
	}

	public int getIndex() {
	    return index;
	}

	public void setIndex(int index) {
	    this.index = index;
	}

	public String getKey() {
	    return key;
	}

	public void setKey(String key) {
	    this.key = key;
	}
    }

}