/**************************************************************************
/* GUI application for document search.
/*
/* Copyright (c) 2003-2004 by Bernhard Bablok (mail@bablokb.de)
/*
/* This library is free software; you can redistribute it and/or modify
/* it under the terms of the GNU Lesser General Public License as published
/* by  the Free Software Foundation; either version 2 of the License or
/* (at your option) any later version.
/*
/* This library 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 Lesser General Public License for more details.
/*
/* You should have received a copy of the GNU Lesser General Public License
/* along with this library; see the file COPYING.LESSER.  If not, write to
/* the Free Software Foundation Inc., 59 Temple Place - Suite 330,
/* Boston, MA  02111-1307 USA
/**************************************************************************/

package de.bablokb.luala.app;

import java.util.*;
import java.io.*;
import java.net.*;
import java.awt.*;
import javax.swing.*;

import gnu.getopt.*;
import org.apache.lucene.document.*;

import de.bablokb.luala.lib.*;
import de.bablokb.luala.lib.event.*;
import de.bablokb.luala.lib.gui.*;

/**
   GUI application for document search.

   <p><strong>TODO:</strong>Add options using getopt.

   @version $Revision: 1.15 $
   @author  $Author: bablokb $
*/

public class GuiSearcher 
                   implements SearchEventListener, ShowDocumentEventListener {

  ////////////////////////////////////////////////////////////////////////////

  /**
     String-constant for the properties-file.
  */

  private static final String 
    GUI_SEARCHER_PROPERTIES = "/GuiSearcher.properties";

  ////////////////////////////////////////////////////////////////////////////

  /**
     The index directory.
  */

  private String iIndexDir;

  ////////////////////////////////////////////////////////////////////////////

  /**
     The browser to use for hyperlinks.
  */

  private String iBrowser;

  ////////////////////////////////////////////////////////////////////////////

  /**
     The path-prefix.
  */

  private String iPathPrefix = "";

  ////////////////////////////////////////////////////////////////////////////

  /**
     The start-page.
  */

  private String iStartPage = "";

  ////////////////////////////////////////////////////////////////////////////

  /**
     The debug-mode.
  */

  private boolean iDebug = false;

  ////////////////////////////////////////////////////////////////////////////

  /**
     The singleton-object of this class.
  */

  private static GuiSearcher iSearcher = new GuiSearcher();

  ////////////////////////////////////////////////////////////////////////////

  /**
     The {@link SearchPanel} for this application.
  */

  private SearchPanel iSearchPanel;

  ////////////////////////////////////////////////////////////////////////////

  /**
     The {@link ResultView} for this application.
  */

  private ResultView iResultView;

  ////////////////////////////////////////////////////////////////////////////

  /**
     The {@link MessageLine} for this application.
  */

  private MessageLine iMessageLine;

  /////////////////////////////////////////////////////////////////////////////

  /**
     A private constructor, since we use the singleton-design pattern.
     Use {@link #getInstance()} to access the singleton.
  */

  private GuiSearcher() {
  }

  /////////////////////////////////////////////////////////////////////////////

  /**
     Query the singleton-instance.

     @return The singleton instance.
  */

  public static GuiSearcher getInstance() {
    return iSearcher;
  }

  ////////////////////////////////////////////////////////////////////////////

  /**
     Display Usage information and exit.
  */

  private void usage() {
    System.out.println("\nusage: java " + GuiSearcher.class.getName() + 
       " -i indexDir -b browser [-p path-prefix] [-dh] start-page\n\n" +
       "valid options:\n" +
       "\t-i indexDir     directory with the index-files (required)\n" +
       "\t-b browser      browser to use for results (required)\n" +
       "\t-p path-prefix  a prefix to prepend to the results\n" +
       "\t-d              display debug-output\n" +
       "\t-h              display usage-information and exit\n"
    );
    System.exit(1);
  }

  ////////////////////////////////////////////////////////////////////////////

  /**
     Parse commandline arguments.

     @param args The cmd-line arguments.
  */

  private void parseArguments(String[] args) {
    Getopt g = new Getopt(GuiSearcher.class.getName(),args, ":i:b:p:dh");
    int c;
    while ((c = g.getopt()) != -1) {
      switch(c)	{
      case 'i':
	iIndexDir = g.getOptarg();
	break;
      case 'b':
	iBrowser = g.getOptarg();
	break;
      case 'p':
	iPathPrefix = g.getOptarg();
	break;
      case 'd':
	iDebug = true;
	break;
      case 'h':
      case ':':
      case '?':
	usage();
	break;
      default:
	break;
      }
    }
    if (g.getOptind() == args.length-1)
      iStartPage = args[g.getOptind()];
    else
      usage();
  }

  ////////////////////////////////////////////////////////////////////////////

  /**
     Check arguments.
  */

  private void checkArguments() {
    if (iIndexDir == null || iBrowser == null || iStartPage == null)
      usage();
    if (! new File(iIndexDir).isDirectory()) {
      System.err.println("error: " + iIndexDir + " does not exist!");
      usage();
    }
  }

  ////////////////////////////////////////////////////////////////////////////

  /**
     Main-program. Currently, the program just supports three command-line
     arguments:
     <ol>
       <li>The index directory
       <li>The browser to use for hyperlinks
       <li>The optional path-prefix for results
     </ol>

     @param args The cmd-line arguments.
  */

  public static void main(String[] args) {
    try {
      GuiSearcher searcher = GuiSearcher.getInstance();
      searcher.parseArguments(args);
      searcher.checkArguments();
      //     searcher.loadProperties();
      searcher.initLogging();
      searcher.createGUI();
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
    
  /////////////////////////////////////////////////////////////////////////////

  /**
     Load a properties-file into the System-properties.
  */

  private void loadProperties() {
    Properties props = System.getProperties();
    try {
      InputStream lStream =
	GuiSearcher.class.getResourceAsStream(GUI_SEARCHER_PROPERTIES);
      props.load(lStream);
      lStream.close();
    } catch (IOException e) {
      e.printStackTrace();
    }
    System.setProperties(props);
  }

  /////////////////////////////////////////////////////////////////////////////

  /**
     Initiate log4j-logging.
  */

  private void initLogging() {
  }

  /////////////////////////////////////////////////////////////////////////////

  /**
     Create GUI of this application.
  */

  private void createGUI() throws Exception {
    iSearchPanel = new SimpleSearchPanel();
    iSearchPanel.addSearchEventListener(this);

    File startPage = new File(iStartPage);
    iResultView  = new HtmlResultView(startPage.toURL());
    iResultView.addShowDocumentEventListener(this);
    GuiSearcherPanel panel = new GuiSearcherPanel(iSearchPanel,iResultView);

    iMessageLine = new MessageLine();
    GuiSearcherFrame frame = new GuiSearcherFrame("Index: " + iIndexDir);
    frame.getContentPane().add(panel,BorderLayout.CENTER);
    frame.getContentPane().add(iMessageLine,BorderLayout.SOUTH);
    frame.pack();
    WindowHelper.center(frame);
    frame.show();
  }

  /////////////////////////////////////////////////////////////////////////////

  /**
     Process the exit-command. <strong>TODO:</strong> save location and other
     settings in preferences.
  */

  public void processExit() {
    System.exit(0);
  }

  /////////////////////////////////////////////////////////////////////////////

  /**
     Process the openIndex-command. <strong>TODO:</strong> implement it!
  */

  public void processOpenIndex() {
  }

  ////////////////////////////////////////////////////////////////////////////

  /**
     {@inheritDoc}
  */

  public void search(SearchEvent se) {
    iMessageLine.start();
    iMessageLine.setText("searching ...");
    final String searchString = se.getSearchString();
    Runnable searchThread = new Runnable() {
      public void run() {
        try {
          SearchEngine engine = new SearchEngine(iIndexDir);
          Document[] results = engine.search(searchString);
          ResultRenderer renderer = new HtmlResultRenderer(iPathPrefix);
          iResultView.setData(renderer.render(results));
	  iMessageLine.stop();
	  iMessageLine.setText("Search finished");
        } catch (Exception ex) {
          ex.printStackTrace();
        }
      }
    };
    SwingUtilities.invokeLater(searchThread);
  }

  ////////////////////////////////////////////////////////////////////////////

  /**
     {@inheritDoc}
  */

  public void showDocument(ShowDocumentEvent sde) {
    iMessageLine.start();
    final String doc =  sde.getName();
    Runnable viewerThread = new Runnable() {
	public void run() {
	  try {
	    Runtime.getRuntime().exec(iBrowser + " " + doc);
	    iMessageLine.stop();
	    iMessageLine.setText("Browser " + iBrowser + " started!");
	  } catch (IOException ex) {
	  }
	}
      };
    new Thread(viewerThread).start();
  }
}