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.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author ulrich
 */
public class OMXLogLeser {
  
  private static final Logger logger = Logger.getLogger(OMXLogLeser.class.getName());
  
  public static final SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
  
  private static final long MILLIS = (long) 1000;
  
  private static final long MINSEC = (long) 60;
      
  /**
   * 
   * <p>Die Spieldauer laut OMX-Log ergibt sich aus dem Zeitstempel des 
   * letzten Eintrags abzueglich des Zeitstempels des 
   * ersten Eintrags abzueglich der Pausen</p>
   * 
   * <p>Eine Pause ist der Zeitraum vom Zeitstempel eines Eintrags mit 
   * <code>Keyboard: character p (0x70)</code> bis zum Zeitstempel des 
   * n&auml;chsten Eintrags mit <code>Keyboard: character p</code></p>
   * 
   * 
   * @param logfile
   * @return  die Spieldauer als String im Format H:MM:SS
   * @throws FileNotFoundException
   * @throws IOException
   * @throws ParseException 
   */
  public String lesen(File logfile) throws FileNotFoundException, IOException, ParseException {    
    boolean inPause = false;
    logger.info("Starting to parse log..");
    Date parseStart = new Date();
    long lineCount = 0;
    InputStream is = new FileInputStream(logfile);
    BufferedReader r = new BufferedReader(new InputStreamReader(is));
    String firstLine = r.readLine();
    ++lineCount;
    String lastLine = "";
    String line = r.readLine();
    Blocks blocks = new Blocks();
    Block currentBlock = new Block();
    while(line != null) {
      ++lineCount;
      if(currentBlock.getStart() == null) {
        currentBlock.setStart(line.substring(0, 8));
      }
      if(line.contains("Keyboard: character p")) {
        if(inPause) {
          currentBlock.setStart(line.substring(0, 8));          
        } else {
          currentBlock.setEnd(line.substring(0, 8));
          blocks.add(currentBlock);
          currentBlock = new Block();
        }
        inPause = !inPause;
      }
      lastLine = line;
      line = r.readLine();
    }
    currentBlock.setEnd(lastLine.substring(0, 8));
    blocks.add(currentBlock);
    Date parseEnd = new Date();
    long timeMillis = parseEnd.getTime() - parseStart.getTime();
    long timeSeconds = timeMillis / MILLIS;
    long secMillis = timeSeconds * MILLIS;
    long restMillis = timeMillis - secMillis;
    logger.log(Level.INFO, 
            "{0} lines parsed in {1} seconds and {2} milliseconds.", 
            new Object[]{lineCount, timeSeconds, restMillis});
    return blocks.getTimeString();
  }
  
  class Block {
    private String start = null;
    private String end = null;
    
    public long getDuration() throws ParseException {
      Date startDate = sdf.parse(start);
      Date endDate = sdf.parse(end);
      return endDate.getTime() - startDate.getTime();
    }

    public String getStart() {
      return start;
    }

    public void setStart(String start) {
      //logger.log(Level.FINER, "Start: ''{0}''", start);
      this.start = start;
    }

    public String getEnd() {
      return end;
    }

    public void setEnd(String end) {
      //logger.log(Level.FINER, "End: ''{0}''", end);
      this.end = end;
    }
    
    
  }
  
  class Blocks {
    
    private final List<Block> blocks = new ArrayList();
    
    public void add(Block block) {
      blocks.add(block);
    }
    
    public long getDuration() throws ParseException {
      long duration = (long) 0;
      Iterator<Block> i = blocks.iterator();
      while(i.hasNext()) {
        Block b = i.next();
        duration += b.getDuration();
      }
      return duration;
    }
    
    public String getTimeString() throws ParseException {
      long diff = getDuration();
      long h = diff / MILLIS / MINSEC / MINSEC;
      long hmillis = h * MINSEC * MINSEC  * MILLIS;
      long m = (diff - hmillis) / MILLIS / MINSEC;
      long mmillis = m * MINSEC * MILLIS;
      long s = (diff - hmillis - mmillis) / MILLIS;
      //logger.log(Level.FINER, "{0}:{1}:{2}", new Object[]{h, m, s});
      return h + ":" + m + ":" + s;
    }
  }
}