/**
 * Copyright (C) 2014-2016 LinkedIn Corp. (pinot-core@linkedin.com)
 *
 * 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.
 */
package com.linkedin.pinot.hadoop.job;

import java.io.InputStream;
import java.util.Properties;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.linkedin.pinot.common.utils.FileUploadUtils;


public class SegmentTarPushJob extends Configured {

  private String _segmentPath;
  private String[] _hosts;
  private String _port;
  public static final int MAX_RETRIES = 5;
  public static final int SLEEP_BETWEEN_RETRIES_IN_SECONDS = 60;

  private static final Logger LOGGER = LoggerFactory.getLogger(SegmentTarPushJob.class);

  public SegmentTarPushJob(String name, Properties properties) {
    super(new Configuration());
    _segmentPath = properties.getProperty("path.to.output") + "/";
    _hosts = properties.getProperty("push.to.hosts").split(",");
    _port = properties.getProperty("push.to.port");

  }

  public void run() throws Exception {
    Configuration conf = new Configuration();
    FileSystem fs = FileSystem.get(conf);
    Path path = new Path(_segmentPath);
    FileStatus[] fileStatusArr = fs.globStatus(path);
    for (FileStatus fileStatus : fileStatusArr) {
      if (fileStatus.isDirectory()) {
        pushDir(fs, fileStatus.getPath());
      } else {
        pushOneTarFile(fs, fileStatus.getPath());
      }
    }

  }

  public void pushDir(FileSystem fs, Path path) throws Exception {
    LOGGER.info("******** Now uploading segments tar from dir: {}", path);
    FileStatus[] fileStatusArr = fs.listStatus(new Path(path.toString() + "/"));
    for (FileStatus fileStatus : fileStatusArr) {
      if (fileStatus.isDirectory()) {
        pushDir(fs, fileStatus.getPath());
      } else {
        pushOneTarFile(fs, fileStatus.getPath());
      }
    }
  }

  public void pushOneTarFile(FileSystem fs, Path path) throws Exception {
    String fileName = path.getName();
    if (!fileName.endsWith(".tar.gz")) {
      return;
    }
    for (String host : _hosts) {
      InputStream inputStream = null;
      try {
        inputStream = fs.open(path);
        fileName = fileName.split(".tar")[0];
        LOGGER.info("******** Upoading file: {} to Host: {} and Port: {} *******", fileName, host, _port);
        try {
          int responseCode = sendSegmentFile(host, _port, fileName, fs, path);
          LOGGER.info("Response code: {}", responseCode);
        } catch (Exception e) {
          LOGGER.error("******** Error Upoading file: {} to Host: {} and Port: {}  *******", fileName, host, _port);
          LOGGER.error("Caught exception during upload", e);
          throw new RuntimeException("Got Error during send tar files to push hosts!");
        }
      } finally {
        inputStream.close();
      }
    }
  }

  public static int sendSegmentFile(final String host, final String port, final String fileName,
      final FileSystem fs, final Path path) {
    int retval = 0;
    for (int numRetries = 0; ; numRetries++) {
      try {
        InputStream inputStream = fs.open(path);
        long length = fs.getFileStatus(path).getLen();
        retval = FileUploadUtils.sendSegmentFile(host, port, fileName, inputStream, length);
        break;
      } catch (Exception e) {
        if (numRetries >= MAX_RETRIES) {
          throw new RuntimeException(e);
        }
        LOGGER.warn("Retry " + numRetries + " of Upload of File " + fileName + " to host " + host
            + " after error trying to send file ");
        try {
          Thread.sleep(SLEEP_BETWEEN_RETRIES_IN_SECONDS * 1000);
        } catch (Exception e1) {
          LOGGER.error("Upload of File " + fileName + " to host " + host + " interrupted while waiting to retry after error");
          throw new RuntimeException(e1);
        }
      }
    }
    return retval;
  }

}