/*
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 *    SerializedModelSaver.java
 *    Copyright (C) 2008 University of Waikato, Hamilton, New Zealand
 *
 */

package weka.gui.beans;

import java.awt.BorderLayout;
import java.beans.EventSetDescriptor;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Vector;

import javax.swing.JPanel;

import weka.core.Environment;
import weka.core.EnvironmentHandler;
import weka.core.Instances;
import weka.core.Tag;
import weka.core.Utils;
import weka.core.xml.KOML;
import weka.core.xml.XStream;

/**
 * A bean that saves serialized models
 * 
 * @author Mark Hall (mhall{[at]}pentaho{[dot]}org
 * @version $Revision: 10534 $
 */
public class SerializedModelSaver extends JPanel implements BeanCommon,
  Visible, BatchClassifierListener, IncrementalClassifierListener,
  BatchClustererListener, EnvironmentHandler, Serializable {

  /** for serialization */
  private static final long serialVersionUID = 3956528599473814287L;

  /**
   * Default visual for data sources
   */
  protected BeanVisual m_visual = new BeanVisual("AbstractDataSink",
    BeanVisual.ICON_PATH + "SerializedModelSaver.gif", BeanVisual.ICON_PATH
      + "SerializedModelSaver_animated.gif");

  /**
   * Non null if this object is a target for any events. Provides for the
   * simplest case when only one incomming connection is allowed.
   */
  protected Object m_listenee = null;

  /**
   * The log for this bean
   */
  protected transient weka.gui.Logger m_logger = null;

  /**
   * The prefix for the file name (model + training set info will be appended)
   */
  private String m_filenamePrefix = "";

  /**
   * The directory to hold the saved model(s)
   */
  private File m_directory = new File(System.getProperty("user.dir"));

  /**
   * File format stuff
   */
  private Tag m_fileFormat;

  public final static int BINARY = 0;
  public final static int KOMLV = 1;
  public final static int XSTREAM = 2;

  /** the extension for serialized models (binary Java serialization) */
  public final static String FILE_EXTENSION = "model";

  /**
   * relative path for the directory (relative to the user.dir (startup
   * directory))?
   */
  private boolean m_useRelativePath = false;

  /**
   * Available file formats. Reflection is used to check if classes are
   * available for deep object serialization to XML
   */
  public static ArrayList<Tag> s_fileFormatsAvailable;
  static {
    s_fileFormatsAvailable = new ArrayList<Tag>();
    s_fileFormatsAvailable.add(new Tag(BINARY, Messages.getInstance()
      .getString("SerializedModelSaver_FileFormatsAvailable_Text_First")
      + FILE_EXTENSION
      + Messages.getInstance().getString(
        "SerializedModelSaver_FileFormatsAvailable_Text_Second"), "", false));
    if (KOML.isPresent()) {
      s_fileFormatsAvailable.add(new Tag(KOMLV, Messages.getInstance()
        .getString("SerializedModelSaver_FileFormatsAvailable_Text_Third")
        + KOML.FILE_EXTENSION
        + FILE_EXTENSION
        + Messages.getInstance().getString(
          "SerializedModelSaver_FileFormatsAvailable_Text_Fourth"), "", false));
    }

    if (XStream.isPresent()) {
      s_fileFormatsAvailable.add(new Tag(XSTREAM, Messages.getInstance()
        .getString("SerializedModelSaver_FileFormatsAvailable_Text_Fifth")
        + XStream.FILE_EXTENSION
        + FILE_EXTENSION
        + Messages.getInstance().getString(
          "SerializedModelSaver_FileFormatsAvailable_Text_Sixth"), "", false));
    }
  }

  /**
   * The environment variables.
   */
  protected transient Environment m_env;

  /**
   * Constructor.
   */
  public SerializedModelSaver() {
    useDefaultVisual();
    setLayout(new BorderLayout());
    add(m_visual, BorderLayout.CENTER);
    m_fileFormat = s_fileFormatsAvailable.get(0);

    m_env = Environment.getSystemWide();
  }

  /**
   * Set a custom (descriptive) name for this bean
   * 
   * @param name the name to use
   */
  @Override
  public void setCustomName(String name) {
    m_visual.setText(name);
  }

  /**
   * Get the custom (descriptive) name for this bean (if one has been set)
   * 
   * @return the custom name (or the default name)
   */
  @Override
  public String getCustomName() {
    return m_visual.getText();
  }

  /**
   * Use the default images for this bean.
   * 
   */
  @Override
  public void useDefaultVisual() {
    m_visual.loadIcons(BeanVisual.ICON_PATH + "SerializedModelSaver.gif",
      BeanVisual.ICON_PATH + "SerializedModelSaver_animated.gif");
    m_visual.setText("SerializedModelSaver");
  }

  /**
   * Set the visual for this data source.
   * 
   * @param newVisual a <code>BeanVisual</code> value
   */
  @Override
  public void setVisual(BeanVisual newVisual) {
    m_visual = newVisual;
  }

  /**
   * Get the visual being used by this data source.
   * 
   */
  @Override
  public BeanVisual getVisual() {
    return m_visual;
  }

  /**
   * Returns true if, at this time, the object will accept a connection
   * according to the supplied EventSetDescriptor.
   * 
   * @param esd the EventSetDescriptor
   * @return true if the object will accept a connection
   */
  @Override
  public boolean connectionAllowed(EventSetDescriptor esd) {
    return connectionAllowed(esd.getName());
  }

  /**
   * Returns true if, at this time, the object will accept a connection
   * according to the supplied event name.
   * 
   * @param eventName the event
   * @return true if the object will accept a connection
   */
  @Override
  public boolean connectionAllowed(String eventName) {
    return (m_listenee == null);
  }

  /**
   * Notify this object that it has been registered as a listener with a source
   * with respect to the supplied event name.
   * 
   * @param eventName the event
   * @param source the source with which this object has been registered as a
   *          listener
   */
  @Override
  public synchronized void connectionNotification(String eventName,
    Object source) {
    if (connectionAllowed(eventName)) {
      m_listenee = source;
    }
  }

  /**
   * Notify this object that it has been deregistered as a listener with a
   * source with respect to the supplied event name.
   * 
   * @param eventName the event
   * @param source the source with which this object has been registered as a
   *          listener
   */
  @Override
  public synchronized void disconnectionNotification(String eventName,
    Object source) {
    if (m_listenee == source) {
      m_listenee = null;
    }
  }

  /**
   * Set a log for this bean.
   * 
   * @param logger a <code>weka.gui.Logger</code> value
   */
  @Override
  public void setLog(weka.gui.Logger logger) {
    m_logger = logger;
  }

  /**
   * Stop any processing that the bean might be doing.
   */
  @Override
  public void stop() {
    // tell the listenee (upstream bean) to stop
    if (m_listenee instanceof BeanCommon) {
      ((BeanCommon) m_listenee).stop();
    }
  }

  /**
   * Returns true if. at this time, the bean is busy with some (i.e. perhaps a
   * worker thread is performing some calculation).
   * 
   * @return true if the bean is busy.
   */
  @Override
  public boolean isBusy() {
    return false;
  }

  /**
   * makes sure that the filename is valid, i.e., replaces slashes, backslashes
   * and colons with underscores ("_").
   * 
   * @param filename the filename to cleanse
   * @return the cleansed filename
   */
  protected String sanitizeFilename(String filename) {
    return filename.replaceAll("\\\\", "_").replaceAll(":", "_")
      .replaceAll("/", "_");
  }

  /**
   * Accept and save a batch trained clusterer.
   * 
   * @param ce a <code>BatchClassifierEvent</code> value
   */
  @Override
  public void acceptClusterer(BatchClustererEvent ce) {
    if (ce.getTestSet() == null
      || ce.getTestOrTrain() == BatchClustererEvent.TEST
      || ce.getTestSet().isStructureOnly()) {
      return;
    }

    Instances trainHeader = ce.getTestSet().getDataSet().stringFreeStructure();
    String titleString = ce.getClusterer().getClass().getName();
    titleString = titleString.substring(titleString.lastIndexOf('.') + 1,
      titleString.length());

    String prefix = "";
    try {
      prefix = m_env.substitute(m_filenamePrefix);
    } catch (Exception ex) {
      String message = Messages.getInstance().getString(
        "SerializedModelSaver_AcceptClusterer_Message_Text_First")
        + statusMessagePrefix()
        + Messages.getInstance().getString(
          "SerializedModelSaver_AcceptClusterer_Message_Text_Second")
        + ex.getMessage();
      if (m_logger != null) {
        m_logger.logMessage(message);
        m_logger.statusMessage(statusMessagePrefix()
          + Messages.getInstance().getString(
            "SerializedModelSaver_AcceptClusterer_StatusMessage_Text_First"));
      } else {
        System.err.println(message);
      }
      return;
    }
    String fileName = "" + prefix + titleString + "_" + ce.getSetNumber() + "_"
      + ce.getMaxSetNumber();
    fileName = sanitizeFilename(fileName);

    String dirName = m_directory.getPath();
    try {
      dirName = m_env.substitute(dirName);
    } catch (Exception ex) {
      String message = Messages.getInstance().getString(
        "SerializedModelSaver_AcceptClusterer_Message_Text_Third")
        + statusMessagePrefix()
        + Messages.getInstance().getString(
          "SerializedModelSaver_AcceptClusterer_Message_Text_Fourth")
        + ex.getMessage();
      if (m_logger != null) {
        m_logger.logMessage(message);
        m_logger.statusMessage(statusMessagePrefix()
          + Messages.getInstance().getString(
            "SerializedModelSaver_AcceptClusterer_StatusMessage_Text_Second"));
      } else {
        System.err.println(message);
      }
      return;
    }
    File tempFile = new File(dirName);
    fileName = tempFile.getAbsolutePath() + File.separator + fileName;

    saveModel(fileName, trainHeader, ce.getClusterer());
  }

  /**
   * Accept and save an incrementally trained classifier.
   * 
   * @param ce the BatchClassifierEvent containing the classifier
   */
  @Override
  public void acceptClassifier(final IncrementalClassifierEvent ce) {
    if (ce.getStatus() == IncrementalClassifierEvent.BATCH_FINISHED) {
      // Only save model when the end of the stream is reached
      Instances header = ce.getStructure();
      String titleString = ce.getClassifier().getClass().getName();
      titleString = titleString.substring(titleString.lastIndexOf('.') + 1,
        titleString.length());

      String prefix = "";
      try {
        prefix = m_env.substitute(m_filenamePrefix);
      } catch (Exception ex) {
        String message = Messages.getInstance().getString(
          "SerializedModelSaver_AcceptClassifier_Message_Text_First")
          + statusMessagePrefix()
          + Messages.getInstance().getString(
            "SerializedModelSaver_AcceptClassifier_Message_Text_Second")
          + ex.getMessage();
        if (m_logger != null) {
          m_logger.logMessage(message);
          m_logger
            .statusMessage(statusMessagePrefix()
              + Messages
                .getInstance()
                .getString(
                  "SerializedModelSaver_AcceptClassifier_StatusMessage_Text_First"));
        } else {
          System.err.println(message);
        }
        return;
      }

      String fileName = "" + prefix + titleString;
      fileName = sanitizeFilename(fileName);

      String dirName = m_directory.getPath();
      try {
        dirName = m_env.substitute(dirName);
      } catch (Exception ex) {
        String message = Messages.getInstance().getString(
          "SerializedModelSaver_AcceptClassifier_Message_Text_Third")
          + statusMessagePrefix()
          + Messages.getInstance().getString(
            "SerializedModelSaver_AcceptClassifier_Message_Text_Fourth")
          + ex.getMessage();
        if (m_logger != null) {
          m_logger.logMessage(message);
          m_logger
            .statusMessage(statusMessagePrefix()
              + Messages
                .getInstance()
                .getString(
                  "SerializedModelSaver_AcceptClassifier_StatusMessage_Text_Second"));
        } else {
          System.err.println(message);
        }
        return;
      }
      File tempFile = new File(dirName);

      fileName = tempFile.getAbsolutePath() + File.separator + fileName;

      saveModel(fileName, header, ce.getClassifier());
    }
  }

  /**
   * Accept and save a batch trained classifier.
   * 
   * @param ce the BatchClassifierEvent containing the classifier
   */
  @Override
  public void acceptClassifier(final BatchClassifierEvent ce) {
    if (ce.getTrainSet() == null || ce.getTrainSet().isStructureOnly()) {
      return;
    }
    Instances trainHeader = new Instances(ce.getTrainSet().getDataSet(), 0);
    String titleString = ce.getClassifier().getClass().getName();
    titleString = titleString.substring(titleString.lastIndexOf('.') + 1,
      titleString.length());

    String prefix = "";
    try {
      prefix = m_env.substitute(m_filenamePrefix);
    } catch (Exception ex) {
      String message = Messages.getInstance().getString(
        "SerializedModelSaver_AcceptClassifier_Message_Text_Fifth")
        + statusMessagePrefix()
        + Messages.getInstance().getString(
          "SerializedModelSaver_AcceptClassifier_Message_Text_Sixth")
        + ex.getMessage();
      if (m_logger != null) {
        m_logger.logMessage(message);
        m_logger.statusMessage(statusMessagePrefix()
          + Messages.getInstance().getString(
            "SerializedModelSaver_AcceptClassifier_StatusMessage_Text_Third"));
      } else {
        System.err.println(message);
      }
      return;
    }

    String fileName = "" + prefix + titleString + "_" + ce.getSetNumber() + "_"
      + ce.getMaxSetNumber();
    fileName = sanitizeFilename(fileName);

    String dirName = m_directory.getPath();
    try {
      dirName = m_env.substitute(dirName);
    } catch (Exception ex) {
      String message = Messages.getInstance().getString(
        "SerializedModelSaver_AcceptClassifier_Message_Text_Seventh")
        + statusMessagePrefix()
        + Messages.getInstance().getString(
          "SerializedModelSaver_AcceptClassifier_Message_Text_Eighth")
        + ex.getMessage();
      if (m_logger != null) {
        m_logger.logMessage(message);
        m_logger.statusMessage(statusMessagePrefix()
          + Messages.getInstance().getString(
            "SerializedModelSaver_AcceptClassifier_StatusMessage_Text_Fourth"));
      } else {
        System.err.println(message);
      }
      return;
    }
    File tempFile = new File(dirName);

    fileName = tempFile.getAbsolutePath() + File.separator + fileName;

    saveModel(fileName, trainHeader, ce.getClassifier());
  }

  /**
   * Helper routine to actually save the models.
   */

  private void saveModel(String fileName, Instances trainHeader, Object model) {
    m_fileFormat = validateFileFormat(m_fileFormat);
    if (m_fileFormat == null) {
      // default to binary if validation fails
      m_fileFormat = s_fileFormatsAvailable.get(0);
    }
    try {
      switch (m_fileFormat.getID()) {
      case KOMLV:
        fileName = fileName + KOML.FILE_EXTENSION + FILE_EXTENSION;
        saveKOML(new File(fileName), model, trainHeader);
        break;
      case XSTREAM:
        fileName = fileName + XStream.FILE_EXTENSION + FILE_EXTENSION;
        saveXStream(new File(fileName), model, trainHeader);
        break;
      default:
        fileName = fileName + "." + FILE_EXTENSION;
        saveBinary(new File(fileName), model, trainHeader);
        break;
      }
    } catch (Exception ex) {
      System.err.println(Messages.getInstance().getString(
        "SerializedModelSaver_SaveModel_Error_Text"));
      if (m_logger != null) {
        m_logger.logMessage(Messages.getInstance().getString(
          "SerializedModelSaver_SaveModel_LogMessage_Text_First")
          + statusMessagePrefix()
          + Messages.getInstance().getString(
            "SerializedModelSaver_SaveModel_LogMessage_Text_Second")
          + " : "
          + ex.getMessage());
        m_logger.statusMessage(statusMessagePrefix()
          + Messages.getInstance().getString(
            "SerializedModelSaver_SaveModel_StatusMessage_Text"));
      }
    }
  }

  /**
   * Save a model in binary form.
   * 
   * @param saveTo the file name to save to
   * @param model the model to save
   * @param header the header of the data that was used to train the model
   *          (optional)
   */
  public static void saveBinary(File saveTo, Object model, Instances header)
    throws IOException {
    ObjectOutputStream os = new ObjectOutputStream(new BufferedOutputStream(
      new FileOutputStream(saveTo)));
    os.writeObject(model);
    // now the header
    if (header != null) {
      os.writeObject(header);
    }
    os.close();
  }

  /**
   * Save a model in KOML deep object serialized XML form.
   * 
   * @param saveTo the file name to save to
   * @param model the model to save
   * @param header the header of the data that was used to train the model
   *          (optional)
   */
  public static void saveKOML(File saveTo, Object model, Instances header)
    throws Exception {
    Vector v = new Vector();
    v.add(model);
    if (header != null) {
      v.add(header);
    }
    v.trimToSize();
    KOML.write(saveTo.getAbsolutePath(), v);
  }

  /**
   * Save a model in XStream deep object serialized XML form.
   * 
   * @param saveTo the file name to save to
   * @param model the model to save
   * @param header the header of the data that was used to train the model
   *          (optional)
   */
  public static void saveXStream(File saveTo, Object model, Instances header)
    throws Exception {
    Vector v = new Vector();
    v.add(model);
    if (header != null) {
      v.add(header);
    }
    v.trimToSize();
    XStream.write(saveTo.getAbsolutePath(), v);
  }

  /**
   * Get the directory that the model(s) will be saved into
   * 
   * @return the directory to save to
   */
  public File getDirectory() {
    return m_directory;
  }

  /**
   * Set the directory that the model(s) will be saved into.
   * 
   * @param d the directory to save to
   */
  public void setDirectory(File d) {
    m_directory = d;
    if (m_useRelativePath) {
      try {
        m_directory = Utils.convertToRelativePath(m_directory);
      } catch (Exception ex) {
      }
    }
  }

  /**
   * Set whether to use relative paths for the directory. I.e. relative to the
   * startup (user.dir) directory
   * 
   * @param rp true if relative paths are to be used
   */
  public void setUseRelativePath(boolean rp) {
    m_useRelativePath = rp;
  }

  /**
   * Get whether to use relative paths for the directory. I.e. relative to the
   * startup (user.dir) directory
   * 
   * @return true if relative paths are to be used
   */
  public boolean getUseRelativePath() {
    return m_useRelativePath;
  }

  /**
   * Get the prefix to prepend to the model file names.
   * 
   * @return the prefix to prepend
   */
  public String getPrefix() {
    return m_filenamePrefix;
  }

  /**
   * Set the prefix to prepend to the model file names.
   * 
   * @param p the prefix to prepend
   */
  public void setPrefix(String p) {
    m_filenamePrefix = p;
  }

  /**
   * Global info for this bean. Gets displayed in the GUI.
   * 
   * @return information about this bean.
   */
  public String globalInfo() {
    return Messages.getInstance().getString(
      "SerializedModelSaver_GlobalInfo_Text");
  }

  /**
   * Set the file format to use for saving.
   * 
   * @param ff the file format to use
   */
  public void setFileFormat(Tag ff) {
    m_fileFormat = ff;
  }

  /**
   * Get the file format to use for saving.
   * 
   * @return the file format to use
   */
  public Tag getFileFormat() {
    return m_fileFormat;
  }

  /**
   * Validate the file format. After this bean is deserialized, classes for XML
   * serialization may not be in the classpath any more.
   * 
   * @param ff the current file format to validate
   */
  public Tag validateFileFormat(Tag ff) {
    Tag r = ff;
    if (ff.getID() == BINARY) {
      return ff;
    }

    if (ff.getID() == KOMLV && !KOML.isPresent()) {
      r = null;
    }

    if (ff.getID() == XSTREAM && !XStream.isPresent()) {
      r = null;
    }

    return r;
  }

  private String statusMessagePrefix() {
    return getCustomName() + "$" + hashCode() + "|";
  }

  /**
   * Set environment variables to use.
   * 
   * @param env the environment variables to use
   */
  @Override
  public void setEnvironment(Environment env) {
    m_env = env;
  }

  // Custom de-serialization in order to set default
  // environment variables on de-serialization
  private void readObject(ObjectInputStream aStream) throws IOException,
    ClassNotFoundException {
    aStream.defaultReadObject();

    // set a default environment to use
    m_env = Environment.getSystemWide();
  }
}
