LangTool.java

/*
 * This file is part of LaTeXDraw.
 * Copyright (c) 2005-2017 Arnaud BLOUIN
 * LaTeXDraw 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.
 * LaTeXDraw is distributed 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.
 */
package net.sf.latexdraw.util;

import java.io.IOException;
import java.net.URISyntaxException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Collections;
import java.util.List;
import java.util.Locale;
import java.util.ResourceBundle;
import java.util.stream.Collectors;
import javax.xml.parsers.DocumentBuilderFactory;
import net.sf.latexdraw.badaboom.BadaboomCollector;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

/**
 * The different localizations of LaTeXDraw.
 * @author Arnaud BLOUIN
 */
public final class LangTool {
	public static final LangTool INSTANCE = new LangTool();
	
	private final ResourceBundle bundle;
	
	private LangTool() {
		super();
		bundle = readLang();
	}

	
	public ResourceBundle getBundle() {
		return bundle;
	}


	/**
	 * Allows to get the language of the program.
	 * @return The read language, or the default language.
	 */
	private ResourceBundle readLang() {
		try {
			final Path xml = Paths.get(LPath.PATH_PREFERENCES_XML_FILE);

			if(Files.exists(xml)) {
	            final Node node = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(Files.newInputStream(xml)).getFirstChild();

	            if(node!=null && node.getNodeName().equals(LNamespace.XML_ROOT_PREFERENCES)) {
	            	final NodeList nl = node.getChildNodes();

		            for(int i=0,size = nl.getLength() ; i<size; i++)
		            	if(nl.item(i).getNodeName().equals(LNamespace.XML_LANG)) {
		            		ResourceBundle bu = loadResourceBundle(Locale.forLanguageTag(nl.item(i).getTextContent()));
		            		if(bu==null) return getDefaultLanguage();
		            		return bu;
		            	}
	            }
			}
		}
		catch(final Exception ex) {
			ex.printStackTrace();
			BadaboomCollector.INSTANCE.add(ex); 
		}
		return getDefaultLanguage();
	}

	
	private Locale getLocaleFromFileName(final String fileName) {
		return Locale.forLanguageTag(LFileUtils.INSTANCE.getFileNameNoExtension(fileName).replaceAll("bundle_", "").replaceAll("_", "-"));
	}
	
	
	public List<Locale> getSupportedLocales() {
		try {
			return Files.list(Paths.get(getClass().getResource("/lang").toURI())).filter(f -> !Files.isDirectory(f) && Files.isReadable(f)).
								map(f -> getLocaleFromFileName(f.getFileName().toString())).collect(Collectors.toList());
		}catch(final IOException | URISyntaxException e) {
			e.printStackTrace();
			BadaboomCollector.INSTANCE.add(e); 
		}
		return Collections.emptyList();
	}
	
	
	/** @return The language used by default. */
	private ResourceBundle getDefaultLanguage() {
		return loadResourceBundle(Locale.getDefault());
	}
	
	
	private ResourceBundle loadResourceBundle(Locale locale) {
		try {
			return ResourceBundle.getBundle("lang.bundle", locale);
		}catch(Exception ex) {
			ex.printStackTrace();
			BadaboomCollector.INSTANCE.add(ex); 
			return null;
		}
	}
}