/*-
 * ============LICENSE_START=======================================================
 * SDC
 * ================================================================================
 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * 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.
 * ============LICENSE_END=========================================================
 */
package org.openecomp.sdc.be.components.distribution.engine;

import com.google.common.util.concurrent.ThreadFactoryBuilder;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import org.openecomp.sdc.be.config.DistributionEngineConfiguration.DistributionNotificationTopicConfig;
import org.openecomp.sdc.common.log.wrappers.Logger;

public class NotificationExecutorService {

    private static final Logger logger = Logger.getLogger(NotificationExecutorService.class.getName());

    public ExecutorService createExcecutorService(DistributionNotificationTopicConfig distributionNotificationTopic) {
        Integer minThreadPoolSize = distributionNotificationTopic.getMinThreadPoolSize();
        if (minThreadPoolSize == null) {
            minThreadPoolSize = 0;
        }
        Integer maxThreadPoolSize = distributionNotificationTopic.getMaxThreadPoolSize();
        if (maxThreadPoolSize == null) {
            maxThreadPoolSize = 10;
        }
        ThreadFactoryBuilder threadFactoryBuilder = new ThreadFactoryBuilder();
        threadFactoryBuilder.setNameFormat("distribution-notification-thread-%d");
        ThreadFactory threadFactory = threadFactoryBuilder.build();
        return new ThreadPoolExecutor(minThreadPoolSize, maxThreadPoolSize, 60L, TimeUnit.SECONDS, new SynchronousQueue<>(), threadFactory);
    }

    public void shutdownAndAwaitTermination(ExecutorService pool, long maxTimeToWait) {
        logger.debug("shutdown NotificationExecutorService");
        pool.shutdown(); // Disable new tasks from being submitted
        try {
            // Wait a while for existing tasks to terminate
            if (!pool.awaitTermination(maxTimeToWait, TimeUnit.SECONDS)) {
                pool.shutdownNow(); // Cancel currently executing tasks

                // Wait a while for tasks to respond to being cancelled
                if (!pool.awaitTermination(maxTimeToWait, TimeUnit.SECONDS)) {
                    logger.debug("Failed to close executor service");
                }
            }
        } catch (InterruptedException ie) {
            // (Re-)Cancel if current thread also interrupted
            pool.shutdownNow();
            // Preserve interrupt status
            Thread.currentThread().interrupt();
        }
    }
}