package eu.dnetlib.dhp.export.zenodo;

import java.io.*;

import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
import org.apache.commons.compress.archivers.tar.TarArchiveOutputStream;
import org.apache.commons.io.IOUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import eu.dnetlib.dhp.application.ArgumentApplicationParser;

public class MakeTar implements Serializable {

	private static final Logger log = LoggerFactory.getLogger(MakeTar.class);

	public static void main(String[] args) throws Exception {
		String jsonConfiguration = IOUtils
			.toString(
				MakeTar.class
					.getResourceAsStream(
						"/eu/dnetlib/dhp/export/input_maketar_parameters.json"));

		final ArgumentApplicationParser parser = new ArgumentApplicationParser(jsonConfiguration);
		parser.parseArgument(args);

		final String outputPath = parser.get("targetPath");
		log.info("hdfsPath: {}", outputPath);

		final String hdfsNameNode = parser.get("nameNode");
		log.info("nameNode: {}", hdfsNameNode);

		final String inputPath = parser.get("sourcePath");
		log.info("input path : {}", inputPath);

		Configuration conf = new Configuration();
		conf.set("fs.defaultFS", hdfsNameNode);

		FileSystem fileSystem = FileSystem.get(conf);

		makeTArArchive(fileSystem, inputPath, outputPath);

	}

	public static void makeTArArchive(FileSystem fileSystem, String inputPath, String outputPath) throws IOException {

		RemoteIterator<LocatedFileStatus> dir_iterator = fileSystem.listLocatedStatus(new Path(inputPath));

		while (dir_iterator.hasNext()) {
			LocatedFileStatus fileStatus = dir_iterator.next();

			Path p = fileStatus.getPath();
			String p_string = p.toString();
			String entity = p_string.substring(p_string.lastIndexOf("/") + 1);

			write(fileSystem, p_string, outputPath + "/" + entity + ".tar", entity);
		}

	}

	private static void write(FileSystem fileSystem, String inputPath, String outputPath, String dir_name)
		throws IOException {

		Path hdfsWritePath = new Path(outputPath);
		FSDataOutputStream fsDataOutputStream = null;
		if (fileSystem.exists(hdfsWritePath)) {
			fileSystem.delete(hdfsWritePath, true);

		}
		fsDataOutputStream = fileSystem.create(hdfsWritePath);

		TarArchiveOutputStream ar = new TarArchiveOutputStream(fsDataOutputStream.getWrappedStream());

		RemoteIterator<LocatedFileStatus> fileStatusListIterator = fileSystem
			.listFiles(
				new Path(inputPath), true);

		while (fileStatusListIterator.hasNext()) {
			LocatedFileStatus fileStatus = fileStatusListIterator.next();

			Path p = fileStatus.getPath();
			String p_string = p.toString();
			if (!p_string.endsWith("_SUCCESS")) {
				String name = p_string.substring(p_string.lastIndexOf("/") + 1);
				TarArchiveEntry entry = new TarArchiveEntry(dir_name + "/" + name + ".json.gz");
				entry.setSize(fileStatus.getLen());
				ar.putArchiveEntry(entry);

				InputStream is = fileSystem.open(fileStatus.getPath());

				BufferedInputStream bis = new BufferedInputStream(is);

				int count;
				byte data[] = new byte[1024];
				while ((count = bis.read(data, 0, data.length)) != -1) {
					ar.write(data, 0, count);
				}
				bis.close();
				ar.closeArchiveEntry();

			}

		}

		ar.close();
	}

}