source: main/trunk/gli/src/org/greenstone/gatherer/file/FileAssociationManager.java@ 24707

/**
 *#########################################################################
 *
 * A component of the Gatherer application, part of the Greenstone digital
 * library suite from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * Author: John Thompson, Greenstone Digital Library, University of Waikato
 *
 * Copyright (C) 1999 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.file;

import java.io.*;
import java.util.regex.*;
import javax.swing.table.*;
import org.greenstone.gatherer.Configuration;
import org.greenstone.gatherer.DebugStream;
import org.greenstone.gatherer.Dictionary;
import org.greenstone.gatherer.gui.FileAssociationDialog;
import org.greenstone.gatherer.gui.PreviewCommandDialog;
import org.greenstone.gatherer.util.ExternalProgram;
import org.greenstone.gatherer.util.StaticStrings;
import org.greenstone.gatherer.util.Utility;
import org.greenstone.gatherer.util.XMLTools;
import org.w3c.dom.*;

public class FileAssociationManager 
    extends AbstractTableModel {
    static final public String FILENAME_ARG = "%1";
    static final private String ESCAPE = "\\\\"; // '\'
    static final private String ESCAPED_ESCAPE = "\\\\\\\\"; // '\\'
    static final private String SPACE = " ";
    static final private String ESCAPED_SPACE = "\\\\ ";
    private Element associations_element;
    private File data_file;   

    public FileAssociationManager() {
    // Retrieve the associations_element from the config
    associations_element = Configuration.getFileAssociations();
    // Initialize the associations. This involves looking through all current associations searching for those with a command of "".
    if(associations_element != null) {
        NodeList entries = associations_element.getElementsByTagName(StaticStrings.ENTRY_ELEMENT);
        for(int i = 0; i < entries.getLength(); i++) {
        Element entry = (Element) entries.item(i);
        String command = XMLTools.getValue(entry);
        // If we encounter a command of ""...
        if(command.length() == 0) {
            // if we are on windows, we default to the start command
            if(Utility.isWindows()) {
            if (Utility.isWindows9x()) {
                XMLTools.setValue(entry, StaticStrings.WIN_9X_OPEN_COMMAND);
            } else {
                XMLTools.setValue(entry, StaticStrings.WIN_OPEN_COMMAND);
            }
            }
            // and if we are on mac, we default to the open program
            else if(Utility.isMac()) {
            XMLTools.setValue(entry, StaticStrings.MAC_OPEN_COMMAND);
            }
            //else { XMLTools.setValue(entry, StaticStrings.LINUX_OPEN_COMMAND); } // assume linux?
        }
        command = null;
        entry = null;
        }
        entries = null;
    }
    else {
        DebugStream.println("Didn't parse anything. About to crash.");
    }
    }
    
    public void edit() {
    FileAssociationDialog dialog = new FileAssociationDialog(this);
    dialog.display(null);
    dialog = null;        
    }

    public String getBrowserCommand(String url) {
    DebugStream.println("Get browser command: " + url);
    // First off we try to retrieve one from the configuration
    String command = Configuration.getPreviewCommand();
    // If that worked, substitute in the url and return
    if(command != null && command.length() > 0) {
        command = command.replaceAll("%1", url);
        DebugStream.println("Result = " + command);
        return command;
    }
    command = null;
    // Failing that we have a guess at a sensible default 
    if(Utility.isWindows()) {
        // we use cmd and start
        if (Utility.isWindows9x()) {
        command = StaticStrings.WIN_9X_OPEN_COMMAND;//"command.com /c start \""+url+"\"";
        } else {
        command = StaticStrings.WIN_OPEN_COMMAND;//"cmd.exe /c start \"\" \""+url+"\"";
        }
    } else if (Utility.isMac()) {
        command = StaticStrings.MAC_OPEN_COMMAND; // "open %1"
    } else {
        // we try to look for a browser
        String [] browsers = new String [] {"mozilla", "netscape"};
        for (int i=0; i<browsers.length; i++) {
        if (isAvailable(browsers[i])) {
            command = browsers[i]+ " %1";
            break;
        }
        }
        //if (command == null) { command = StaticStrings.LINUX_OPEN_COMMAND; } // "xdg-open %1"
    }

    // if we still haven't found something, prompt the user
    if (command == null) {
        PreviewCommandDialog dialog = new PreviewCommandDialog();
        command = dialog.display();
        dialog.dispose();
        dialog = null;
    }

    // Store the result if any
    if(command != null && !command.equals("")) {
        Configuration.setPreviewCommand(command);
        command = command.replaceAll(FILENAME_ARG, url);
        DebugStream.println("Result = " + command);
        return command;
    }
    // if we haven't got a command by now, we'll never get one
    DebugStream.println("Result = null");
    return null;
    
    }

    public int getColumnCount() {
    return 2;
    }

    public String getColumnName(int column) {
    String name;
    switch(column) {
    case 0:
        name = Dictionary.get("FileAssociationDialog.Table.Extension");
        break;
    default:
        name = Dictionary.get("FileAssociationDialog.Table.Command");
    }
    return name;
    }
   
    public String [] getCommand(File file) {
    String command = null;
    String [] commands = null;
    if(file.isFile()) {
        // Determine extension
        String filename = file.getAbsolutePath();
        String extension = filename.substring(filename.lastIndexOf(".") + 1);
        // Try to retrieve a value from cache
        Element entry = getCommand(extension);
        if(entry != null) {
        ///ystem.err.println("Retrieved Value From Cache");
        command = XMLTools.getValue(entry); 
        }
        if(command == null || command.length() == 0) {
        ///ystem.err.println("No Existing Command");
        // If command is null, and we are on windows try searching the registry.
        if(Utility.isWindows()) {
            //try the start command
            if (Utility.isWindows9x()) {
            command = StaticStrings.WIN_9X_OPEN_COMMAND;
            } else {
            command = StaticStrings.WIN_OPEN_COMMAND;
            }
            
        }
        
        // If we are on a mac, default to using the open program
        else if(Utility.isMac()) {
            command = StaticStrings.MAC_OPEN_COMMAND;
        }
        
        //else { command = StaticStrings.LINUX_OPEN_COMMAND; } // If linux, default to using xdg-open
        
        // Otherwise display the dialog and ask the user to enter launching command.
        if(command == null || command.length() == 0) {
            ///ystem.err.println("Show Dialog");
            // Show the dialog which forces a user to select the launch command for a certain file.
            FileAssociationDialog dialog = new FileAssociationDialog(this);
            command = dialog.display(extension);
            dialog = null;
        }

        // Hopefully by now we have a command, or else we're never going to get one. Add the association.
        if (command != null && !command.equals("")) {
            // If no previous entry existed create one.
            if(entry == null) {
            entry = associations_element.getOwnerDocument().createElement(StaticStrings.ENTRY_ELEMENT);
            entry.setAttribute(StaticStrings.EXTENSION_ATTRIBUTE, extension);
            associations_element.appendChild(entry);
            }
            // Replace the text in this node. Remember to replace the dummy filename with %1 - I dont think the filename will ever be in the comand now
            //XMLTools.setValue(entry, command.replaceAll(filename, FILENAME_ARG));
            XMLTools.setValue(entry, command);
        }
        }

        if (command != null && !command.equals("")) {
        // Make the command into a string []        
        commands = command.split(" ");

        // Now substitute any occurrences of %1 with its filename
        // Note this is done after the split on spaces to avoid
        // any conflict with filenames with spaces in them.

        // We have to fix filename under windows to escape the backslashes
        filename = filename.replaceAll(ESCAPE, ESCAPED_ESCAPE);

        for (int i=0; i<commands.length; i++) {
            // Replace %1 with the appropriate filename
            commands[i] = commands[i].replaceAll(FILENAME_ARG, filename);
        }
        }
        
        entry = null;
        extension = null;
        filename = null;
    }
    return commands;
    }

    public Element getCommand(String target_extension) {
    NodeList entries = associations_element.getElementsByTagName(StaticStrings.ENTRY_ELEMENT);
    for(int i = 0; i < entries.getLength(); i++) { 
        Element entry = (Element) entries.item(i);
        String extension = entry.getAttribute(StaticStrings.EXTENSION_ATTRIBUTE);
        if(extension.equalsIgnoreCase(target_extension)) {
        entries = null;
        extension = null;
        return entry;
        }
    }
    entries = null;
    return null;
    }

    public String getCommandString(String target_extension) {
    Element entry = getCommand(target_extension);
    if(entry != null) {
        return XMLTools.getValue(entry);
    }
    else {
        return "";
    }
    }

    public String getExtension(int index) {
    NodeList entries = associations_element.getElementsByTagName(StaticStrings.ENTRY_ELEMENT);
    if(0 <= index && index < entries.getLength()) {
        Element entry = (Element) entries.item(index);
        return entry.getAttribute(StaticStrings.EXTENSION_ATTRIBUTE);
    }
    return "";
    }

    public int getRowCount() {
    return size();
    }

    public Object getValueAt(int row, int column) {
    String extension = getExtension(row);
    switch(column) {
    case 0:
        return extension;
    default:
        return getCommandString(extension);
    }
    }

    public void save() {
    }

    public void setCommand(String extension, String command) {
    DebugStream.println("Set Launch: " + extension + " with " + command);
    // Retrieve any existing entry for this extension
    Element entry = getCommand(extension);
    // If no previous entry existed create one.
    if(entry == null && command != null) {
        entry = associations_element.getOwnerDocument().createElement(StaticStrings.ENTRY_ELEMENT);
        entry.setAttribute(StaticStrings.EXTENSION_ATTRIBUTE, extension);
        associations_element.appendChild(entry);
    }

    if(command != null) {
        // Replace the text in this node. If the user has used filename instead of %1 then too bad.
        XMLTools.setValue(entry, command);
    }
    else {
        // Remove the entry
        associations_element.removeChild(entry);
    }
    entry = null;
    fireTableDataChanged(); // Can't be anymore efficient as DOM does not gareuntee ordering of new child nodes is consistant
    }

    public int size() {
    NodeList entries = associations_element.getElementsByTagName(StaticStrings.ENTRY_ELEMENT);
    return entries.getLength();
    }


    protected boolean isAvailable(String program) {
    try {
        ExternalProgram e = new ExternalProgram("which", program);
        e.exitProgram();
        String out = e.getLineOfProgramOutput();
        if (out == null) {
        return false;
        }
        return true;
    } catch (Exception exc) {
        return false;
    }
    }
}