/**
 * <copyright> Copyright 2006 by Know-Center, Graz, Austria </copyright>
 * PDF-AS has been contracted by the E-Government Innovation Center EGIZ, a
 * joint initiative of the Federal Chancellery Austria and Graz University of
 * Technology.
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * http://www.osor.eu/eupl/
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 *
 * $Id: FileHelper.java,v 1.2 2006/05/15 12:05:21 wlackner Exp $
 */
package at.knowcenter.wag.egov.egiz.tools;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

import org.apache.log4j.Logger;

import at.knowcenter.wag.egov.egiz.cfg.ConfigLogger;

/**
 * This class provides file reader and writer methods. All methods are static!
 * 
 * @author wlackner
 */
public class FileHelper {
  /**
   * The logger definition.
   */
  private static final Logger logger_ = ConfigLogger.getLogger(FileHelper.class);

  /**
   * This method reads a file by reading line by line.
   * 
   * @param fileName the file to be read
   * @return the content string of the file
   */
  public static String readFromFile(String fileName) {
    String file_string = null;
    logger_.trace("Looking for file: " + fileName);
    try {
      BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(fileName), "UTF-8"));
      logger_.trace("Reading file: " + fileName);
      String line = null;
      file_string = "";
      while ((line = reader.readLine()) != null) {
        file_string += line;
      }
      reader.close();
      logger_.debug("File successfully read: " + fileName);
    } catch (FileNotFoundException e) {
      logger_.debug("File not found: " + fileName);
    } catch (IOException e) {
      logger_.debug("Error reading file: " + fileName);
    }
    return file_string;
  }

  /**
   * This method reads a file by reading line by line.
   * 
   * @param fileName the file to be read
   * @return the content string of the file
   */
  public static String readFromInputStream(InputStream inputStream) {
    String file_string = null;
    if (inputStream == null) {
       return null;
    }
    try {
      BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));
      String line = null;
      file_string = "";
      while ((line = reader.readLine()) != null) {
        file_string += line;
      }
      reader.close();
    } catch (IOException e) {
      logger_.debug("Error reading inputstream.");
    }
    return file_string;
  }

  /**
   * This method writes a file line by line.
   * 
   * @param fileName the file to be written
   * @param fileString the content to be written
   * @return true if the file could be written sucessfully, false otherwise
   */
  public static boolean writeToFile(String fileName, String fileString) {
    BufferedWriter writer;
    try {
      FileWriter fwriter = new FileWriter(fileName);
      writer = new BufferedWriter(fwriter);
      writer.write(fileString);
      writer.close();
    } catch (IOException e) {
      logger_.info("File:" + fileName + " can not be written. Cause:" + e.getMessage());
      return false;
    }
    return true;
  }
}