/**
 *############################################################################
 * A component of the Greenstone Librarian Interface, part of the Greenstone
 * digital library suite from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * Author: Michael Dewsnip, NZDL Project, University of Waikato, NZ
 *
 * Copyright (C) 2004 New Zealand Digital Library Project
 *
 * 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.
 *############################################################################
 */

package org.greenstone.gatherer.greenstone;


import java.io.*;
import java.lang.*;
import java.net.*;
import java.util.*;
import javax.swing.*;
import org.greenstone.gatherer.Configuration;
import org.greenstone.gatherer.DebugStream;
import org.greenstone.gatherer.Dictionary;
import org.greenstone.gatherer.Gatherer;
import org.greenstone.gatherer.util.PortFinder;
import org.greenstone.gatherer.util.Utility;


public class LocalLibraryServer
{
    static final private int WAITING_TIME = 20; // number of seconds to wait for the server to start and stop

    static final private String ADD_COMMAND = "?a=config&cmd=add-collection&c=";
    static final private String RELEASE_COMMAND = "?a=config&cmd=release-collection&c=";
    static final private String QUIT_COMMAND = "?a=config&cmd=kill";

    static private LLSSiteConfig llssite_cfg_file = null;
    static private File local_library_server_file = null;

    static private boolean running = false;
    static private String ID = "greenstone-server"; // a sort of process ID

    // Need to use sockets to tell the server program to terminate when on Linux
    // The socket port number that we will use to communicate the termination
    static private int port;

    // The server is persistent if it does not have to reload all the values
    // over and over again each time. Tomcat is persistent and fastcgi is too,
    // but the Apache webserver is not persistent by default.
    // Change the initialisation of this value depending on whether fastcgi is 
    // on. At the moment, this does not apply to the Linux' local library server.
    static private boolean isPersistentServer = Utility.isWindows();

    static public void addCollection(String collection_name)
    {
	if (isPersistentServer) {
	    config(ADD_COMMAND + collection_name);
	}
    }


    // Used to send messages to the local library
    static private void config(String command)
    {
	if (!isPersistentServer) {
	    return;
	}
	if (Configuration.library_url == null) {
	    System.err.println("Error: Trying to configure local library with null Configuration.library_url!");
	    return;
	}

	try {
	    URL url = new URL(Configuration.library_url.toString() + command);
	    HttpURLConnection library_connection = (HttpURLConnection) url.openConnection();

	    // It's very important that we read the output of the command
	    // This ensures that the command has actually finished
	    // (The response code is returned immediately)
	    InputStream library_is = library_connection.getInputStream();
	    BufferedReader library_in = new BufferedReader(new InputStreamReader(library_is, "UTF-8"));
	    String library_output_line = library_in.readLine();
	    while (library_output_line != null) {
		DebugStream.println("Local library server output: " + library_output_line);
		library_output_line = library_in.readLine();
	    }
	    library_in.close();

	    int response_code = library_connection.getResponseCode();
	    if (response_code >= HttpURLConnection.HTTP_OK && response_code < HttpURLConnection.HTTP_MULT_CHOICE) {
		DebugStream.println("200 - Complete.");
	    }
	    else {
		DebugStream.println("404 - Failed.");
	    }
	}
	catch (Exception exception) {
	    DebugStream.printStackTrace(exception);
	}
    }

    // Used to send messages to the local server on Linux
    static private boolean sendMessageToServer(String message) {
	if(Utility.isWindows()) {
	    return false;
	}
	
	if(port == -1) {
	    return false;
	}
	    
	try {
	    Socket clientSocket = new Socket("localhost", port);
	    Writer writer = new BufferedWriter(new OutputStreamWriter(clientSocket.getOutputStream()));
	    writer.write(message);
	    writer.close();
	    writer = null;
	} catch (Exception e) {
	    System.err.println("An exception occurred when trying to send the message: " + message 
			       + "\nto the LocalLibraryServer.\n" + e);
	    return false;
	} 
	return true;
    }

    static public boolean isRunning()
    {
	if (!running) return false; // if the url is pending, then running would also be false (server not started up yet)

	llssite_cfg_file.load(true);
	String url = llssite_cfg_file.getURL();
	if (url == null) return false;
	
	// Called by Gatherer to check whether we need to stop the server.
	// if the url is pending, then the GSI hasn't started the server up yet
	// Already covered in !running
	//if (url.equals(LLSSiteConfig.URL_PENDING)) return false;

	return true;
    }


    static public void releaseCollection(String collection_name)
    {
	if (isPersistentServer) {
	    config(RELEASE_COMMAND + collection_name);
	}
    }

    static public void start(String gsdl_path, String local_library_server_file_path)
    {
	// Check the local library server file (server.exe or gs2-server.sh) exists
	local_library_server_file = new File(local_library_server_file_path);
	
	if (!local_library_server_file.exists()) {
	    DebugStream.println("No local library at given file path.");
	
	    String defaultServerFilename = Utility.isWindows() ? "server.exe" : "gs2-server.sh";
	    local_library_server_file = new File(gsdl_path + defaultServerFilename);
	    if (!local_library_server_file.exists()) {
		DebugStream.println("No local library at all.");
		return;
	    }
	}	

	// In the case of the Local Library Server on Linux, we need to do an extra test:
	// If GS2 was not configured with --enable-apache-httpd, then there is no apache webserver folder,
	// even though the gs2-server.sh file would still be there. That means if the folder is absent 
	// we still have no local library server.
	if(!Utility.isWindows()) {
	    File localLinuxServerFolder = new File(gsdl_path, "apache-httpd");
	    if (!localLinuxServerFolder.exists() && !localLinuxServerFolder.isDirectory()) {
		DebugStream.println("The web server does not exist at " 
				    + localLinuxServerFolder.getAbsolutePath() + "\nNo local library at all. Trying web library");
		return;
	    }
	}

	llssite_cfg_file = new LLSSiteConfig(local_library_server_file);
		
	// If the user launched the GSI independent of GLI, but user has not pressed
	// Enter Library yet, then we will obtain the previewURL later.
	if(LocalLibraryServer.isURLPending()) {
	    // running is still false when the URL is pending because only GSI is running, not the server
	    return;
	} else if(llssite_cfg_file.isIndependentGSI()) {
	    // there is a url, it's not pending, and it is llssite.cfg: meaning GSI has started up
	    return;	    
	}

	// Spawn local library server process
	String local_library_server_command = local_library_server_file.getAbsolutePath() + getExtraLaunchArguments(llssite_cfg_file);

	// Check if the server is already running
	String url = llssite_cfg_file.getURL();
	if (url != null) {
	    // If it is already running then set the Greenstone web server address and we're done
	    // E.g. if previously GLI was not properly shut down, the URL property (signifying 
	    // the server is still running) would still be in the glisite_cfg file.
	    try {
		Configuration.library_url = new URL(url);
		running = true;

		// Run the server interface
		Gatherer.spawnApplication(local_library_server_command, ID);
		return;
	    }
	    catch (MalformedURLException exception) {
		DebugStream.printStackTrace(exception);
	    }
	}	

	// Configure the server for immediate entry
	//llssite_cfg_file.set();

	// Spawn local library server process
	Gatherer.spawnApplication(local_library_server_command, ID);
	
	// Wait until program has started
	try {
	    testServerRunning(); // will set running = true when the server is up and running successfully	    
	} catch (IOException bad_url_connection) {
	    try {
		// If this fails then we try changing the url to be localhost
		Configuration.library_url = new URL(llssite_cfg_file.getLocalHostURL());
		DebugStream.println("Try connecting to server on local host: '" + Configuration.library_url + "'");
		URLConnection connection = Configuration.library_url.openConnection();
		connection.getContent();
		running = true;
		
	    } catch (IOException worse_url_connection) {
		DebugStream.println("Can't connect to server on either address.");
		Configuration.library_url = null;
		running = false;
	    }
	}
    }


    static public void stop()
    {
	if (!running) {
	    // also the case if the URL is pending in an independently launched GSI
	    return;
	}

	// don't (can't) shutdown the GSI/server if it was launched independent of GLI
	if(llssite_cfg_file.isIndependentGSI()) {
	    return;
	}

	// Send the command for it to exit.
	if (isPersistentServer) {
	    config(QUIT_COMMAND);
	} else {
	    if(sendMessageToServer("QUIT")) {
		Gatherer.terminateApplication(ID);
	    } else {
		System.err.println("Unable to stop the server, since there's no communication port to send the quit msg over."
				   + "\nPlease stop the local Greenstone server manually.");	    
	    }
	}

	// Wait until program has stopped, by reloading and checking the URL field
	llssite_cfg_file.load(false);
	int attempt_count = 0;
	String url = llssite_cfg_file.getURL();
	while (url != null && !url.equals(LLSSiteConfig.URL_PENDING)) { // if pending, the server is already stopped (not running)
	    new OneSecondWait();  // Wait one second (give or take)
	    llssite_cfg_file.load(false);
	    attempt_count++;

	    // After waiting for the specified time, ask the user whether they want to wait for that long again
	    if (attempt_count == WAITING_TIME) {
		int try_again = JOptionPane.showConfirmDialog(Gatherer.g_man, Dictionary.get("Server.QuitTimeOut", Integer.toString(WAITING_TIME)),
							      Dictionary.get("General.Warning"), JOptionPane.YES_NO_OPTION);
		if (try_again == JOptionPane.NO_OPTION) {
		    return;
		}
		attempt_count = 0;
	    }
	    // read the url again to see if it's updated
	    url = llssite_cfg_file.getURL();
	}

	// Restore the llssite_cfg.
	llssite_cfg_file.restore();

	// If the local server is still running then our changed values will get overwritten.
	url = llssite_cfg_file.getURL();
	if (url != null && !url.equals(LLSSiteConfig.URL_PENDING)) {
	    JOptionPane.showMessageDialog(Gatherer.g_man, Dictionary.get("Server.QuitManual"), Dictionary.get("General.Error"), JOptionPane.ERROR_MESSAGE);
	}

	running = false;
    }
    
    static private String getExtraLaunchArguments(LLSSiteConfig site_cfg_file) {
	String args = " " + site_cfg_file.getSiteConfigFilename();

	if(Utility.isWindows()) {
	    return args;
	}
	
	// Else, when running the Local Library Server on Linux, need to provide a port argument
	try {
	    PortFinder portFinder = new PortFinder(50100, 100);
	    port = portFinder.findPortInRange(false); // silent mode
	} catch(Exception e) {
	    System.err.println("Exception when trying to find an available port: " + e);
	    port = -1;
	}
	
	return args + " --quitport=" + port;
    }


    // This method first tests whether there is a URL in the llssite_cfg_file 
    // and after that appears, it tests whether the URL is functional.
    static private void testServerRunning() throws IOException {
	// Wait until program has started, by reloading and checking the URL field
	llssite_cfg_file.load(false);
	int attempt_count = 0;
	while (llssite_cfg_file.getURL() == null) {
	    new OneSecondWait();  // Wait one second (give or take)
	    llssite_cfg_file.load(false);
	    attempt_count++;

	    // After waiting for the specified time, ask the user whether they want to wait for that long again
	    if (attempt_count == WAITING_TIME) {
		int try_again = JOptionPane.showConfirmDialog(Gatherer.g_man, Dictionary.get("Server.StartUpTimeOut", Integer.toString(WAITING_TIME)),
							      Dictionary.get("General.Warning"), JOptionPane.YES_NO_OPTION);
		if (try_again == JOptionPane.NO_OPTION) {
		    return;
		}
		attempt_count = 0;
	    }
	}
	
	// Ta-da. Now the url should be available
	try {
	    Configuration.library_url = new URL(llssite_cfg_file.getURL());
	}
	catch (MalformedURLException exception) {
	    DebugStream.printStackTrace(exception);
	}

	// A quick test involves opening a connection to get the home page for this collection
	try {
	    DebugStream.println("Try connecting to server on config url: '" + Configuration.library_url + "'");
	    URLConnection connection = Configuration.library_url.openConnection();
	    connection.getContent();
	    running = true;
	}
	catch (IOException bad_url_connection) {
	    throw bad_url_connection;
	}

	
    }

    /** Returns true if we're waiting on the user to click on Enter Library button
     * in an independently launched GSI (one not launched by GLI). */
    static public boolean isURLPending() {
	/*if(Configuration.library_url != null) {
	    System.err.println("**** Configuration.library_url: " + Configuration.library_url );
	    return false; // don't need to do anything as we already have the url
	    }*/

	llssite_cfg_file.load(true); // don't force reload, load only if modified

	String url = llssite_cfg_file.getURL();

	if(url != null) {
	    if(url.equals(LLSSiteConfig.URL_PENDING)) {
		running = false; // imagine if they restarted an external GSI
		return true; 
	    } else {
		// a valid URL at last
		try {
		    Configuration.library_url = new URL(url);
		    running = true;
		}
		catch (MalformedURLException exception) {
		    exception.printStackTrace();
		    DebugStream.printStackTrace(exception);
		}
		return false;
	    }
	}

	// If either the URL is null--which means no independent GSI (Greenstone server interface
	// app) was launched--or if the 'URL' doesn't say it's pending, then we're not waiting
	return false;
    }

    static public void checkServerRunning() {
	if (!running) return; // don't worry about it if it's not supposed to be running 
	llssite_cfg_file.load(true); // don't force reload, load only if modified
	
	String url = llssite_cfg_file.getURL();
	if(url != null) {
	    try {
		Configuration.library_url = new URL(url);
	    }
	    catch (MalformedURLException exception) {
		DebugStream.printStackTrace(exception);
		exception.printStackTrace();
	    }
	} else {
	    // need to restart the server again
 
	    // if we were running an independently launched GSI before, but the GSI has been
	    // exited, it would need to be relaunched, but from within GLI (dependent) this time.
	    if(llssite_cfg_file.isIndependentGSI()) {
		// first save the current configFile (llssite.cfg), then set to use glisite.cfg
		llssite_cfg_file.save();
		llssite_cfg_file.relaunchAsDependentGSI(local_library_server_file);
	    } else {
		// We were using glisite.cfg before, don't need to swap config files
		llssite_cfg_file.set();
	    }
	    // Spawn local library server process
	    String local_library_server_command = local_library_server_file.getAbsolutePath() + getExtraLaunchArguments(llssite_cfg_file);
	    running = false;
	    Gatherer.spawnApplication(local_library_server_command, ID);
	    try {
		testServerRunning(); // don't return until the webserver is up and running
	    } catch (IOException bad_url_connection) {
		DebugStream.println("Can't connect to server on address " + Configuration.library_url);
		running = false;
	    }
	}
    }

    static private class OneSecondWait
    {
	public OneSecondWait()
	{
	    synchronized(this) {
		try {
		    wait(1000);
		}
		catch (InterruptedException exception) {
		}
	    }
	}
    }


    static public class LLSSiteConfig
	extends LinkedHashMap 
    {
	private File configFile;

	private File llssite_cfg;
	private File glisite_cfg;
	private String autoenter_initial;
	private String start_browser_initial;

	private long lastModified = 0;
    
	static final private String AUTOENTER = "autoenter";
	static final private String COLON = ":";
	static final private String ENTERLIB = "enterlib";
	static final private String FALSE = "0";
	static final private String GLISITE_CFG = "glisite.cfg";
	static final private String GSDL = "greenstone"; // httpprefix is no longer /gsdl but /greenstone
	static final private String LLSSITE_CFG = "llssite.cfg";
	static final private String LOCAL_HOST = "http://localhost"; 
	static final private String PORTNUMBER = "portnumber";
	static final private String SEPARATOR = "/";
	static final private String SPECIFIC_CONFIG = "--config=";
	static final private String STARTBROWSER = "start_browser";
	static final private String TRUE = "1";
	static final private String URL = "url";

	static final public String URL_PENDING = "URL_pending";

	public LLSSiteConfig(File server_exe) {
	    debug("New LLSSiteConfig for: " + server_exe.getAbsolutePath());
	    
	    llssite_cfg = new File(server_exe.getParentFile(), LLSSITE_CFG);
	    glisite_cfg = new File(server_exe.getParentFile(), GLISITE_CFG);

	    configFile = null;

	    autoenter_initial = null;
	    start_browser_initial = null;
	    
	    // first test if server was started independently of GLI
	    // if so, the config file we'd be using would be llssite.cfg
	    if(!usingLLS_configFile()) { // if we were using llssite_cfg, this would have loaded it in
		// else we try using the glisite configfile
		useGLISiteCfg(server_exe);
	    }

	    if(configFile != null && configFile.exists()) {
		System.err.println("Using configfile: " + configFile);
		lastModified = configFile.lastModified();
	    }
	}

	/** Tries to get a glisite.cfg file and then loads it, setting it as the configFile */
	public void useGLISiteCfg(File server_exe) {
	    if(!glisite_cfg.exists()) { // create it from the templates or the llssite.cfg file
		
		File llssite_cfg_in = new File(server_exe.getParentFile(), LLSSITE_CFG+".in");
		File glisite_cfg_in = new File(server_exe.getParentFile(), GLISITE_CFG+".in");
		
		// need to generate glisite_cfg from glisite_cfg_in, llssite_cfg or llssite.cfg.in
		if(glisite_cfg_in.exists()) {
		    copyConfigFile(glisite_cfg_in, glisite_cfg, false);    
		} 
		else if(llssite_cfg_in.exists()) { 
		    copyConfigFile(llssite_cfg_in, glisite_cfg_in, true); // adjust for glisite.cfg
		    copyConfigFile(glisite_cfg_in, glisite_cfg, false);    
		}
		else if(llssite_cfg.exists()) {
		    copyConfigFile(llssite_cfg, glisite_cfg, true);        // adjust for glisite.cfg
		}
		else {
		    debug("Neither the file glisite.cfg nor llssite.cfg can be found!");
		}
	    }
	    // use the config file now
	    if(glisite_cfg.exists()) {
		configFile = glisite_cfg;
		load(false); // force reload
	    } 
	}

	/** Tests whether the server interface is up, running independently of GLI
	 * If so, we don't need to launch the server interface.
	 * The server interface may not have started up the server itself though
	 * (in which case the server URL would be URL_PENDING).
	 * This method returns true if the server interface has already started
	 * and, if so, it would have loaded in the llssite_cfg configFile.
	 */
	private boolean usingLLS_configFile() {
	    if(!llssite_cfg.exists()) {
		return false;
	    }

	    // check if the configfile contains the URL line
	    configFile = llssite_cfg;
	    load(false); // force load

	    if(getURL() == null) {
		configFile = null;
		clear(); // we're not using llssite_cfg, so clear the values we just read
		return false;
	    }

	    //System.err.println("***** we're using llssite_configfile, url:" + getURL());
	    return true;
	}
	
	/** @return true if GSI was started up independently and outside of GLI. 
	 * In such a case, GLI would be using llssite_cfg. */
	public boolean isIndependentGSI() {
	    return (configFile == llssite_cfg);
	}

	/** Call this when an independently launched GSI server has been stopped
	 * (one using llssite_cfg) and GLI needs to next launch another server.
	 * In such a case, since GLI itself is relaunching the GSI, we use glisite_cfg.
	*/
	public void relaunchAsDependentGSI(File server_exe) {
		useGLISiteCfg(server_exe);
	}

	public boolean exists() {
	    return configFile.exists();
	}

	public String getLocalHostURL() {
	    StringBuffer url = new StringBuffer(LOCAL_HOST);
	    url.append(COLON);
	    url.append((String)get(PORTNUMBER));
	    String enterlib = (String)get(ENTERLIB);
	    if(enterlib == null || enterlib.length() == 0) {
		// Use the default /gsdl and hope for the best.
		url.append(SEPARATOR);
		url.append(GSDL);
	    }
	    else {
		if(!enterlib.startsWith(SEPARATOR)) {
		    url.append(SEPARATOR);
		}
		url.append(enterlib);
	    }
	    enterlib = null;
	    debug("Found Local Library Address: " + url.toString());
	    return url.toString();
	}

	/** @return the cmd-line parameter for the configfile used to launch
	 * the server through GLI: --config <glisite.cfg/llssite.cfg file path>. */
	public String getSiteConfigFilename() {
	    return SPECIFIC_CONFIG + configFile.getAbsolutePath();
	}

	public String getURL() {
	    // URL is made from url and portnumber
	    String url = (String) get(URL);

	    // server interface is already up, independent of GLI
	    // but it has not started the server (hence URL is pending) 
	    if(url != null && url.equals(URL_PENDING)) {
		return url;
	    }

	    if(!Utility.isWindows()) {
		return url;
	    }

	    if(url != null) {
		StringBuffer temp = new StringBuffer(url);
		temp.append(COLON);
		temp.append((String)get(PORTNUMBER));
		String enterlib = (String)get(ENTERLIB);
		if(enterlib == null || enterlib.length() == 0) {
		    // Use the default /greenstone prefix and hope for the best.
		    temp.append(SEPARATOR);
		    temp.append(GSDL);
		}
		else {
		    if(!enterlib.startsWith(SEPARATOR)) {
			temp.append(SEPARATOR);
		    }
		    temp.append(enterlib);
		}
		enterlib = null;
		url = temp.toString();
	    }
	    debug("Found Local Library Address: " + url);
	    return url;
	}

	public boolean isModified() {
	    return (lastModified != configFile.lastModified());
	}

	public void load(boolean reloadOnlyIfModified) {	    

	    if(configFile == null) {
		debug(configFile.getAbsolutePath() + " cannot be found!");
	    }

	    if(isModified()) {
		lastModified = configFile.lastModified();
	    } else if(reloadOnlyIfModified) {
		return; // asked to reload only if modified. Don't reload since not modified
	    }

	    if(configFile.exists()) {
		debug("Load: " + configFile.getAbsolutePath());
		clear();
		try {
		    BufferedReader in = new BufferedReader(new FileReader(configFile));
		    String line = null;
		    while((line = in.readLine()) != null) {
			String key = null;
			String value = null;
			int index = -1;
			if((index = line.indexOf("=")) != -1 && line.length() >= index + 1) {
			    key = line.substring(0, index);
			    value = line.substring(index + 1);
			}
			else {
			    key = line;
			}
			put(key, value);
		    }
		    in.close();
		}
		catch (Exception error) {
		    error.printStackTrace();
		}
	    }
	    else {
		debug(configFile.getAbsolutePath() + " cannot be found!");
	    }
	}

	/** Restore the autoenter value to its initial value, and remove url if present. */
	public void restore() {
	    if(configFile != null) {
		// Delete the file
		configFile.delete();
	    }
	    else {
		debug("Restore Initial Settings");
		put(AUTOENTER, autoenter_initial);
		put(STARTBROWSER, start_browser_initial);
		remove(URL);
		save();
	    }
	}

	public void set() {
	    debug("Set Session Settings");
	    if(autoenter_initial == null) {
		autoenter_initial = (String) get(AUTOENTER);
		debug("Remember autoenter was: " + autoenter_initial);
	    }
	    put(AUTOENTER, TRUE);
	    if(start_browser_initial == null) {
		start_browser_initial = (String) get(STARTBROWSER);
		debug("Remember start_browser was: " + start_browser_initial);
	    }
	    put(STARTBROWSER, FALSE);
	    save();
	}

	private void debug(String message) {
	    ///ystem.err.println(message);
	}

	private void save() {
	    //debug("Save: " + llssite_cfg.getAbsolutePath());
	    debug("Save: " + configFile.getAbsolutePath());
	    try {
		//BufferedWriter out = new BufferedWriter(new FileWriter(llssite_cfg, false));
		BufferedWriter out = new BufferedWriter(new FileWriter(configFile, false));
		for(Iterator keys = keySet().iterator(); keys.hasNext(); ) {
		    String key = (String) keys.next();
		    String value = (String) get(key);
		    out.write(key, 0, key.length());
		    if(value != null) {
			out.write('=');
			
			// if the server is using llssite.cfg, don't overwrite its default
			// autoenter and startbrowser values
			if(configFile == llssite_cfg && (key == AUTOENTER || key == STARTBROWSER)) {
			    if(key == AUTOENTER) {
				out.write(autoenter_initial, 0, autoenter_initial.length());
			    } else { // STARTBROWSER
				out.write(start_browser_initial, 0, start_browser_initial.length());
			    }
			 } else {
			     out.write(value, 0, value.length());
			}
		    }
		    out.newLine();
		}
		out.flush();
		out.close();
	    }
	    catch (Exception error) {
		error.printStackTrace();
	    }
	}

	private static void copyConfigFile(File source_cfg, File dest_cfg, boolean setToGliSiteDefaults) {
	    // source_cfg file should exist
	    // dest_cfg file should not yet exist
	    // If setToGliSiteDefaults is true, then GLIsite.cfg's default configuration 
	    // is applied to concerned lines: autoenter=1, and startbrowser=0

	    try {
		BufferedReader in = new BufferedReader(new FileReader(source_cfg));
		BufferedWriter out = new BufferedWriter(new FileWriter(dest_cfg, false));
		
		String line = null;
		while((line = in.readLine()) != null) {
		    
		    if(setToGliSiteDefaults) {
			if(line.startsWith(AUTOENTER)) {
			    line = AUTOENTER+"=1";
			}
			else if(line.startsWith(STARTBROWSER)) {
			    line = STARTBROWSER+"=0";
			}
		    }
		
		    // write out the line
		    out.write(line + "\n");
		}
		
		out.flush();
		in.close();
		out.close();
	    } catch(Exception e) {
		System.err.println("Exception occurred when trying to copy the config file "
				   + source_cfg.getName() + " to " + dest_cfg.getName() + ": " + e);
		e.printStackTrace();
	    }
	}
    }
}