/*******************************************************************************
 * Copyright (c) 2007, 2010 Association for Decentralized Information Management
 * in Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.utils.datastructures;

import java.io.PrintStream;
import java.util.concurrent.TimeUnit;
import java.util.function.BiConsumer;


/**
 * @author Tuukka Lehtonen
 */
public final class TimingUtil {

    public abstract static class NamedRunnable implements Runnable {
        String name;
        public NamedRunnable(String name) {
            this.name = name;
        }
        @Override
        public String toString() {
            return name;
        }
    }

    public static class PrintCallback implements BiConsumer<Long, TimeUnit> {
        String task;
        PrintStream stream;
        PrintCallback(String task) {
            this(task, System.out);
        }
        PrintCallback(String task, PrintStream stream) {
            this.task = task;
            this.stream = stream;
        }
        @Override
        public void accept(Long arg1, TimeUnit arg2) {
            stream.println(task + " took " + arg1 + " " + arg2.toString());
        }
    };

    public static void time(Runnable runnable) {
        time(runnable, System.out);
    }

    public static void time(Runnable runnable, PrintStream stream) {
        time(runnable, TimeUnit.MILLISECONDS, new PrintCallback(runnable.toString(), stream));
    }

    public static void time(Runnable runnable, TimeUnit reportTimeUnit, PrintStream stream) {
        time(runnable, reportTimeUnit, new PrintCallback(runnable.toString(), stream));
    }

    public static void time(Runnable runnable, TimeUnit reportTimeUnit, BiConsumer<Long, TimeUnit> result) {
        long start = System.nanoTime();
        runnable.run();
        long end = System.nanoTime();
        result.accept(reportTimeUnit.convert(end-start, TimeUnit.NANOSECONDS), reportTimeUnit);
    }

}