/* Copyright (c) 2013-2014 Boundless and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Distribution License v1.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/org/documents/edl-v10.html
 *
 * Contributors:
 * Gabriel Roldan (Boundless) - initial implementation
 */
package org.locationtech.geogig.metrics;

import java.lang.management.ManagementFactory;

import org.locationtech.geogig.api.Platform;
import org.locationtech.geogig.di.GeogigModule;
import org.locationtech.geogig.storage.ConfigDatabase;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.inject.AbstractModule;

/**
 * Guice module to be used jointly with {@link GeogigModule}, that logs command ellapsed time to a
 * file.
 * <p>
 * The {@code metrics.enabled} (boolean) <b>local</b> configuration property is used to
 * enable/disable logging tracking of command ellapsed time.
 * <p>
 * The following loggers are used:
 * <ul>
 * <li>{@code org.locationtech.geogig.metrics.csv}: used to log command times as they happen, with the format
 * {@code <op name:string>, <start time in millis:long>, <ellapsed time in millis:double>, <success:boolean>}
 * <li>{@code org.locationtech.geogig.metrics.stack}: used to log the stack of command timings whenever a "root"
 * command (that is, one called by client code instead of from another command) finishes. Contains
 * an indented, multiline, stack of commands called with each timing and the relative percent of
 * time each represents to the total time taken by the "root" command. For example:
 * 
 * <pre>
 * <code>
 * LogOp -> 128.31 MILLISECONDS (100.00%), success: true
 *   RevParse -> 114.40 MILLISECONDS (89.16%), success: true
 *       RefParse -> 107.08 MILLISECONDS (83.46%), success: true
 *           ResolveObjectType -> 92.02 MILLISECONDS (71.72%), success: true
 * </code>
 * </pre>
 * 
 * <li>{@code org.locationtech.geogig.metrics.memory}: used to log heap and non heap memory usage, every two
 * seconds, in the format
 * {@code <timestamp>,<heap memory usage in MB>,<non heap mem usage in MB>,<estimated number of objects pending finalization> }
 * 
 * </ul>
 * 
 */
public class MetricsModule extends AbstractModule {

    public static final Logger METRICS_LOGGER = LoggerFactory.getLogger("org.locationtech.geogig.metrics.csv");

    public static final Logger COMMAND_STACK_LOGGER = LoggerFactory
            .getLogger("org.locationtech.geogig.metrics.stack");

    public static final Logger MEMORY_LOGGER = LoggerFactory.getLogger("org.locationtech.geogig.metrics.memory");

    public static final String METRICS_ENABLED = "metrics.enabled";

    public static final long startTimeSecs = ManagementFactory.getRuntimeMXBean().getStartTime() / 1000;

    @Override
    protected void configure() {

        // Provider<Platform> platform = getProvider(Platform.class);
        // Provider<ConfigDatabase> configDb = getProvider(ConfigDatabase.class);

        // final Matcher<Class> stagingDatabase = subclassesOf(StagingDatabase.class);
        // final Matcher<Class> objectDatabase = subclassesOf(ObjectDatabase.class).and(
        // Matchers.not(stagingDatabase));
        //
        // bindInterceptor(objectDatabase, new MethodMatcher(ObjectDatabase.class, "putAll",
        // Iterator.class), new NamedMeteredInterceptor(platform, configDb,
        // "ObjectDatabase.putAll"));
        //
        // bindInterceptor(stagingDatabase, new MethodMatcher(StagingDatabase.class, "putAll",
        // Iterator.class), new NamedMeteredInterceptor(platform, configDb,
        // "StagingDatabase.putAll"));
        //
        // bindInterceptor(objectDatabase, new MethodMatcher(ObjectDatabase.class, "close"),
        // new NamedMeteredInterceptor(platform, configDb, "ObjectDatabase.close"));
        //
        // bindInterceptor(stagingDatabase, new MethodMatcher(StagingDatabase.class, "close"),
        // new NamedMeteredInterceptor(platform, configDb, "StagingDatabase.close"));

        // bind JVM metrics to the repository life cycle
        final HeapMemoryMetricsService jvmMetricsService = new HeapMemoryMetricsService(
                getProvider(Platform.class), getProvider(ConfigDatabase.class));

        GeogigModule.bindDecorator(binder(), new RepositoryDecorator(jvmMetricsService));
    }

}