package de.uhilger.avdirektor;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.logging.Logger;

/**
 *
 * @author ulrich
 */
public class OMXLogLeser {
  
  private static final Logger logger = Logger.getLogger(OMXLogLeser.class.getName());
      
  public String lesen(File logfile) throws FileNotFoundException, IOException {    
    InputStream is = new FileInputStream(logfile);
    BufferedReader r = new BufferedReader(new InputStreamReader(is));
    String firstLine = r.readLine();
    String lastLine = "";
    if(firstLine != null) {
      long size = logfile.length();
      long pos = size - (long) 1000;
      logger.info("Size: " + size + ", Pos: " + pos); // 2.341.930 Bytes
      long skipped = r.skip(pos);
      logger.info("skipped: " + skipped);
      String line = r.readLine();
      while(line != null) {
        lastLine = line;
        logger.info(lastLine);
        line = r.readLine();
      }
    }
    r.close();
    is.close();
    StringBuilder sb = new StringBuilder();
    sb.append("\r\n---");
    sb.append("\r\nfirst line:\r\n");
    sb.append(firstLine);
    sb.append("\r\n\r\nlastLine\r\n");
    sb.append(lastLine);
    String lines = sb.toString();
    logger.info(lines);
    return lines;
  }
  
}