/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.activemq.broker.scheduler;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

import java.io.File;
import java.io.IOException;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

import org.apache.activemq.store.kahadb.scheduler.JobSchedulerStoreImpl;
import org.apache.activemq.util.ByteSequence;
import org.apache.activemq.util.IOHelper;
import org.apache.activemq.util.Wait;
import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.LogManager;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class JobSchedulerStoreCheckpointTest {

    static final Logger LOG = LoggerFactory.getLogger(JobSchedulerStoreCheckpointTest.class);

    private JobSchedulerStoreImpl store;
    private JobScheduler scheduler;
    private ByteSequence payload;

    @Before
    public void setUp() throws Exception {

        // investigate gc issue - store usage not getting released
        org.apache.logging.log4j.core.Logger.class.cast(LogManager.getLogger(JobSchedulerStoreImpl.class)).setLevel(Level.TRACE);

        File directory = new File("target/test/ScheduledJobsDB");
        IOHelper.mkdirs(directory);
        IOHelper.deleteChildren(directory);
        startStore(directory);

        byte[] data = new byte[8192];
        for (int i = 0; i < data.length; ++i) {
            data[i] = (byte) (i % 256);
        }

        payload = new ByteSequence(data);
    }

    protected void startStore(File directory) throws Exception {
        store = new JobSchedulerStoreImpl();
        store.setDirectory(directory);
        store.setCheckpointInterval(5000);
        store.setCleanupInterval(10000);
        store.setJournalMaxFileLength(10 * 1024);
        store.start();
        scheduler = store.getJobScheduler("test");
        scheduler.startDispatching();
    }

    private int getNumJournalFiles() throws IOException {
        return store.getJournal().getFileMap().size();
    }

    @After
    public void tearDown() throws Exception {
        scheduler.stopDispatching();
        store.stop();
    }

    @Test
    public void testStoreCleanupLinear() throws Exception {
        final int COUNT = 10;
        final CountDownLatch latch = new CountDownLatch(COUNT);
        scheduler.addListener(new JobListener() {
            @Override
            public void scheduledJob(String id, ByteSequence job) {
                latch.countDown();
            }
        });

        long time = TimeUnit.SECONDS.toMillis(30);
        for (int i = 0; i < COUNT; i++) {
            scheduler.schedule("id" + i, payload, "", time, 0, 0);
        }

        int size = scheduler.getAllJobs().size();
        assertEquals(size, COUNT);

        LOG.info("Number of journal log files: {}", getNumJournalFiles());
        // need a little slack so go over 60 seconds
        assertTrue(latch.await(70, TimeUnit.SECONDS));
        assertEquals(0, latch.getCount());

        for (int i = 0; i < COUNT; i++) {
            scheduler.schedule("id" + i, payload, "", time, 0, 0);
        }

        LOG.info("Number of journal log files: {}", getNumJournalFiles());
        // need a little slack so go over 60 seconds
        assertTrue(latch.await(70, TimeUnit.SECONDS));
        assertEquals(0, latch.getCount());

        assertTrue("Should be only one log left: " + getNumJournalFiles(), Wait.waitFor(new Wait.Condition() {

            @Override
            public boolean isSatisified() throws Exception {
                return getNumJournalFiles() == 1;
            }
        }, TimeUnit.MINUTES.toMillis(2)));

        LOG.info("Number of journal log files: {}", getNumJournalFiles());
    }

    @Test
    public void testColocatedAddRemoveCleanup() throws Exception {
        final CountDownLatch latch = new CountDownLatch(1);
        scheduler.addListener(new JobListener() {
            @Override
            public void scheduledJob(String id, ByteSequence job) {
                latch.countDown();
            }
        });

        byte[] data = new byte[1024];
        for (int i = 0; i < data.length; ++i) {
            data[i] = (byte) (i % 256);
        }

        long time = TimeUnit.SECONDS.toMillis(2);
        scheduler.schedule("Message-1", new ByteSequence(data), "", time, 0, 0);

        assertTrue(latch.await(70, TimeUnit.SECONDS));
        assertEquals(0, latch.getCount());

        scheduler.schedule("Message-2", payload, "", time, 0, 0);
        scheduler.schedule("Message-3", payload, "", time, 0, 0);

        assertTrue("Should be only one log left: " + getNumJournalFiles(), Wait.waitFor(new Wait.Condition() {

            @Override
            public boolean isSatisified() throws Exception {
                return getNumJournalFiles() == 1;
            }
        }, TimeUnit.MINUTES.toMillis(2)));

        LOG.info("Number of journal log files: {}", getNumJournalFiles());
    }
}
