/*
 * Copyright (C) 2016 Didier Clermonté <dclermonte@april.org>
 * Copyright (C) 2016 Christian Pierre Momon <christian.momon@devinsy.fr>
 *
 * This file is part of Siba.
 *
 * Siba is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.dclermonte.siba.model;

import java.io.BufferedOutputStream;
import java.io.Closeable;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.ResourceBundle;

import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
import org.apache.commons.compress.archivers.tar.TarArchiveOutputStream;
import org.apache.commons.compress.compressors.gzip.GzipCompressorOutputStream;
import org.apache.commons.compress.utils.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.dclermonte.siba.SibaException;

/**
 *
 * @author dclermonte
 *
 */

public class SibaManager
{
	private static final ResourceBundle BUNDLE = ResourceBundle.getBundle("org.dclermonte.siba.model.messages"); //$NON-NLS-1$

	/**
	 * This method perform the backup.
	 *
	 * @param fileToSave
	 * @param target
	 * @return
	 * @throws SibaException
	 */
	public static File backup(final File fileToSave, File target) throws SibaException
	{
		File result;
		try
		{
			if ((fileToSave == null) || !(fileToSave.exists()))
			{
				throw new SibaException(BUNDLE.getString("sourceNotExist.text"));
			}
			else
			{
				if (!(fileToSave.isDirectory()))
				{
					throw new SibaException(BUNDLE.getString("NotDirectorySource.text"));
				}
				else
				{
					if ((target == null))
					{
						target = new File(System.getProperty("user.dir"));
					}
					if (!(target.isDirectory()))
					{
						throw new SibaException(BUNDLE.getString("NotDirectoryTarget.text"));
					}
					else
					{
						int pathLength = fileToSave.getParentFile().getAbsolutePath().length();
						LocalDateTime date = LocalDateTime.now();
						DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH'h'mm'mn'ss's'");
						String textDate = date.format(formatter);
						String outputFileNameWithoutExtension = fileToSave.getName() + "-" + textDate;

						result = new File(target + "/" + outputFileNameWithoutExtension + ".tgz");
						OutputStream gzipOutputStream = new GzipCompressorOutputStream(
								new BufferedOutputStream(new FileOutputStream(result)));
						TarArchiveOutputStream out = new TarArchiveOutputStream(gzipOutputStream);
						directoryToSave(fileToSave, out, pathLength);
						out.close();
						fileCheckMD5(result, target + "/" + outputFileNameWithoutExtension + ".tgz.md5");
					}
				}
			}
		}
		catch (IOException ioExceptionBackup)
		{
			throw new SibaException(BUNDLE.getString("ioExceptionBackup.text"), ioExceptionBackup); //$NON-NLS-1$
		}
		finally
		{
			Closeable out = null;
			IOUtils.closeQuietly(out);
		}
		//
		return result;
	}

	/**
	 * This method is used to check the file.
	 *
	 * @param choosenFile
	 * @return
	 * @throws SibaException
	 */
	public static boolean check(final File choosenFile) throws SibaException
	{
		boolean result;
		try
		{
			if (choosenFile.exists() && (choosenFile.length() > 32))
			{
				FileReader fileReader = new FileReader(choosenFile);
				char[] md5 = new char[32];
				byte[] md5byte = new byte[32];
				char[] fileToCheck = new char[(int) (choosenFile.length()) - 32];
				String md5String = new String();
				for (int index = 0; index < 32; index++)
				{
					md5[index] = (char) fileReader.read();
					md5byte[index] = (byte) md5[index];
					md5String = md5String + md5[index];
				}
				fileReader.read();
				String fileNameToString = new String();
				for (int index = 36; index < (choosenFile.length() + 2); index++)
				{
					fileToCheck[index - 36] = (char) fileReader.read();
					fileNameToString = fileNameToString + fileToCheck[index - 36];
				}

				fileReader.close();
				File fileToCheck1;
				if (choosenFile.isAbsolute())
				{
					fileToCheck1 = new File(choosenFile.getParent() + "/" + fileNameToString);
				}
				else
				{
					String path = System.getProperty("user.dir");
					fileToCheck1 = new File(path + "/" + fileNameToString);
				}

				if (StringUtils.equals(md5String, md5(fileToCheck1)))
				{
					result = true;
				}
				else
				{
					result = false;
				}
			}
			else
			{
				throw new SibaException(BUNDLE.getString("NotExistFileToCheck.text"));
			}
		}
		catch (IOException ioExceptionCheck)
		{
			throw new SibaException(BUNDLE.getString("ioExceptionCheck.text"), ioExceptionCheck); //$NON-NLS-1$
		}
		//
		return result;
	}

	/**
	 *
	 * This method generate ArchiveEntry.
	 *
	 * @param directory
	 * @param outputStream
	 * @param pathLength
	 * @throws SibaException
	 */
	public static void directoryToSave(final File directory, final TarArchiveOutputStream outputStream,
			final int pathLength) throws SibaException
	{
		try
		{
			for (File file : directory.listFiles())
			{

				if (file.isDirectory())
				{
					if (file.listFiles().length == 0)
					{
						TarArchiveEntry tarArchiveEntry = new TarArchiveEntry(file);
						String pathPartiel = file.getPath().substring(pathLength);
						tarArchiveEntry.setName(pathPartiel);
						outputStream.putArchiveEntry(tarArchiveEntry);
						outputStream.closeArchiveEntry();
					}
					else
					{
						directoryToSave(file, outputStream, pathLength);
					}

				}
				else
				{
					TarArchiveEntry tarArchiveEntry = new TarArchiveEntry(file);
					String pathPartiel = file.getPath().substring(pathLength);
					tarArchiveEntry.setName(pathPartiel);
					outputStream.putArchiveEntry(tarArchiveEntry);
					IOUtils.copy(new FileInputStream(file), outputStream);
					outputStream.closeArchiveEntry();

				}
			}
		}
		catch (IOException ioExceptionTarEntry)
		{
			throw new SibaException(BUNDLE.getString("ioExceptionTarEntry.text"), ioExceptionTarEntry); //$NON-NLS-1$
		}
	}

	/**
	 *
	 * This method Generate the file with MD5.
	 *
	 * @param directoryToSave
	 * @param destination
	 * @return
	 * @throws SibaException
	 */
	public static File fileCheckMD5(final File directoryToSave, final String destination) throws SibaException
	{
		File result;
		try
		{
			result = new File(destination);
			FileWriter fileWriter = new FileWriter(result);
			fileWriter.write(md5(directoryToSave));
			String newLine = System.getProperty("line.separator");
			fileWriter.append(" " + directoryToSave.getName() + newLine);
			fileWriter.close();
		}
		catch (IOException ioExceptionFileMD5)
		{
			throw new SibaException(BUNDLE.getString("ioExceptionFileMD5.text"), ioExceptionFileMD5); //$NON-NLS-1$
		}
		//
		return result;
	}

	/**
	 * This method calculate the MD5 itself.
	 *
	 * @param input
	 * @return
	 * @throws SibaException
	 */
	public static String md5(final File input) throws SibaException
	{
		String result;
		StringBuilder hashString = new StringBuilder();
		try
		{
			byte[] byteInput = new byte[(int) input.length()];
			FileInputStream fileInputStream = new FileInputStream(input);
			for (int index1 = 0; index1 < input.length(); index1++)
			{
				byteInput[index1] = (byte) fileInputStream.read();
			}
			byte[] hash = null;
			MessageDigest messageDigest = MessageDigest.getInstance("MD5");
			hash = messageDigest.digest(byteInput);

			for (int index = 0; index < hash.length; index++)
			{
				String hex = Integer.toHexString(hash[index]);
				if (hex.length() == 1)
				{
					hashString.append('0');
					hashString.append(hex.charAt(hex.length() - 1));
				}
				else
				{
					hashString.append(hex.substring(hex.length() - 2));
				}
			}
			fileInputStream.close();
		}
		catch (NoSuchAlgorithmException noSuchAlgorithmException)
		{
			throw new SibaException(BUNDLE.getString("noSuchAlgorithm.text"), noSuchAlgorithmException); //$NON-NLS-1$
		}
		catch (IOException ioException)
		{
			throw new SibaException(BUNDLE.getString("ioExceptionMD5.text"), ioException); //$NON-NLS-1$
		}
		result = hashString.toString();
		//
		return result;
	}

}