Dépôt officiel du code source de l'ERP OpenConcerto

/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

 *

 * Copyright 2011 OpenConcerto, by ILM Informatique. All rights reserved.

 *

 * The contents of this file are subject to the terms of the GNU General Public License Version 3

 * only ("GPL"). You may not use this file except in compliance with the License. You can obtain a

 * copy of the License at http://www.gnu.org/licenses/gpl-3.0.html See the License for the specific

 * language governing permissions and limitations under the License.

 *

 * When distributing the software, include this License Header Notice in each file.

 */

 package org.openconcerto.utils.i18n;

import org.openconcerto.utils.Log;

import org.openconcerto.utils.i18n.TranslationPool.Mode;

import java.io.IOException;

import java.io.InputStream;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Collections;

import java.util.HashMap;

import java.util.List;

import java.util.Locale;

import java.util.Map;

import java.util.ResourceBundle.Control;

import java.util.function.Consumer;

import javax.xml.XMLConstants;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.NodeList;

import org.xml.sax.SAXException;

import net.jcip.annotations.GuardedBy;

import net.jcip.annotations.ThreadSafe;

@ThreadSafe

public class TranslationManager {

    public static final void setVMLocale(Locale locale) {

        Locale.setDefault(locale);

        // As explained in Locale.setDefault() javadoc : "be prepared to reinitialize

        // locale-sensitive code". As ResourceBundle.getBundle(), this throws RuntimeException if no

        // instance can be created.

        TranslationManager.createDefaultInstance();

        // nothing to do for TM

    }

    private static final Locale FALLBACK_LOCALE = Locale.ENGLISH;

    private static final Control CONTROL = new I18nUtils.SameLanguageControl() {

        @Override

        public Locale getFallbackLocale(String baseName, Locale locale) {

            if (!locale.equals(FALLBACK_LOCALE))

                return FALLBACK_LOCALE;

            return null;

        }

    };

    public static final Control getControl() {

        return CONTROL;

    }

    static public interface Loader extends Consumer<TranslationManager> {

    }

    private static final String BASENAME = "translation";

    private static final TranslationPool<TranslationManager, RuntimeException> POOL = new TranslationPool<TranslationManager, RuntimeException>() {

        @Override

        protected TranslationManager createTM(Locale l) throws RuntimeException {

            assert Thread.holdsLock(POOL);

            // Allow some apps to not create an instance at all

            if (classes.isEmpty())

                return null;

            final TranslationManager res = new TranslationManager(l);

            res.setTranslations(classes, true);

            return res;

        }

    };

    /**

     * Create the default instance if needed. Must be called each time {@link TM#getDefaultLocale()}

     * changes otherwise {@link #getInstance()} will throw an exception.

     *

     * @return the instance for the default locale, <code>null</code> if

     *         {@link #addTranslationStreamFromClass(Class)} wasn't called.

     */

    public static final TranslationManager createDefaultInstance() {

        return POOL.get(TM.getDefaultLocale(), Mode.OPTIONAL_CREATE);

    }

    public static final TranslationManager getInstance() {

        return getInstance(TM.getDefaultLocale());

    }

    // TODO throw exception

    public static final TranslationManager createInstance(final Locale l) {

        return POOL.get(l);

    }

    /**

     * Get an instance already created by {@link #createInstance(Locale)}. This method won't block,

     * that's what createInstance() is for.

     *

     * @param l the locale

     * @return the cached instance.

     */

    public static final TranslationManager getInstance(final Locale l) {

        return POOL.getCreated(l);

    }

    @GuardedBy("POOL")

    private static final List<Object> classes = new ArrayList<>();

    public static final void addTranslationStreamFromClass(Class<?> c) {

        _addLoader(c);

    }

    public static final void addLoader(final Loader loader) {

        _addLoader(loader);

    }

    private static final void _addLoader(final Object loader) {

        synchronized (POOL) {

            classes.add(loader);

            for (final TranslationManager tm : POOL.getCreated()) {

                tm.addTranslations(loader, true);

            }

        }

    }

    public static final void removeTranslationStreamFromClass(Class<?> c) {

        _removeLoader(c);

    }

    public static final void removeLoader(final Loader loader) {

        _removeLoader(loader);

    }

    private static final void _removeLoader(final Object o) {

        synchronized (POOL) {

            if (classes.remove(o)) {

                for (final TranslationManager tm : POOL.getCreated()) {

                    tm.setTranslations(classes, false);

                }

            }

        }

    }

    private final Locale locale;

    private final Object trMutex = new Object();

    @GuardedBy("trMutex")

    private Map<String, String> menuTranslation;

    @GuardedBy("trMutex")

    private Map<String, String> itemTranslation;

    @GuardedBy("trMutex")

    private Map<String, String> actionTranslation;

    private TranslationManager(final Locale locale) {

        this.locale = locale;

    }

    public final Locale getLocale() {

        return this.locale;

    }

    private void checkNulls(String id, String label) {

        if (id == null)

            throw new NullPointerException("null id");

        if (label == null)

            throw new NullPointerException("null label");

    }

    // Menus in menu bar and menu items

    public String getTranslationForMenu(String id) {

        synchronized (this.trMutex) {

            return this.menuTranslation.get(id);

        }

    }

    public void setTranslationForMenu(String id, String label) {

        checkNulls(id, label);

        synchronized (this.trMutex) {

            this.menuTranslation.put(id, label);

        }

    }

    // Items labels in panels

    public String getTranslationForItem(String id) {

        synchronized (this.trMutex) {

            return this.itemTranslation.get(id);

        }

    }

    public void setTranslationForItem(String id, String label) {

        checkNulls(id, label);

        synchronized (this.trMutex) {

            this.itemTranslation.put(id, label);

        }

    }

    // Actions (buttons or contextual menus)

    public String getTranslationForAction(String id) {

        synchronized (this.trMutex) {

            return this.actionTranslation.get(id);

        }

    }

    public void setTranslationForAction(String id, String label) {

        checkNulls(id, label);

        synchronized (this.trMutex) {

            this.actionTranslation.put(id, label);

        }

    }

    private void setTranslations(final Collection<?> classes, final boolean warn) {

        synchronized (this.trMutex) {

            this.menuTranslation = new HashMap<>();

            this.itemTranslation = new HashMap<>();

            this.actionTranslation = new HashMap<>();

            if (warn && classes.isEmpty()) {

                Log.get().warning("TranslationManager has no resources to load (" + this.getLocale() + ")");

            }

            for (Object o : classes) {

                this.addTranslations(o, warn);

            }

        }

    }

    private void addTranslations(final Object o, final boolean warn) {

        if (o instanceof Class) {

            final Class<?> c = (Class<?>) o;

            boolean loaded = loadTranslation(this.getLocale(), c);

            if (warn && !loaded) {

                Log.get().warning("TranslationManager was unable to load translation " + c.getCanonicalName() + " for locale " + this.getLocale());

            }

        } else {

            final Loader loader = (Loader) o;

            loader.accept(this);

        }

    }

    // return all existing (e.g fr_CA only specify differences with fr)

    private List<String> findResources(final Locale locale, final Class<?> c, final boolean rootLast) {

        final Control cntrl = CONTROL;

        final List<String> res = new ArrayList<>();

        final String baseName = c.getPackage().getName() + "." + BASENAME;

        // test emptiness to not mix languages

        for (Locale targetLocale = locale; targetLocale != null && res.isEmpty(); targetLocale = cntrl.getFallbackLocale(baseName, targetLocale)) {

            for (final Locale candidate : cntrl.getCandidateLocales(baseName, targetLocale)) {

                res.add(cntrl.toResourceName(cntrl.toBundleName(baseName, candidate), "xml"));

            }

        }

        if (!rootLast)

            Collections.reverse(res);

        return res;

    }

    private boolean loadTranslation(final Locale l, final Class<?> c) {

        boolean translationLoaded = false;

        // FIXME : l'implementation de Java est lente

        // com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl : 60 ms!

        // On pourrait passer à 1ms avec Piccolo...

        final DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();

        final DocumentBuilder dBuilder;

        try {

            dbFactory.setFeature(XMLConstants.FEATURE_SECURE_PROCESSING, true);

            dbFactory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);

            dBuilder = dbFactory.newDocumentBuilder();

        } catch (ParserConfigurationException e) {

            throw new IllegalStateException("Couldn't create DocumentBuilder", e);

        }

        // we want more specific translations to replace general ones, i.e. root Locale first

        for (final String rsrcName : findResources(l, c, false)) {

            // create new instances to check if there's no duplicates in each resource

            final Map<String, String> menuTranslation = new HashMap<>(), itemTranslation = new HashMap<>(), actionTranslation = new HashMap<>();

            try (final InputStream input = c.getClassLoader().getResourceAsStream(rsrcName)) {

                if (input == null)

                    continue;

                final Document doc = dBuilder.parse(input);

                // Menus

                loadTranslation(doc, "menu", menuTranslation);

                // Items (title, labels not related to fields...)

                loadTranslation(doc, "item", itemTranslation);

                // Actions

                loadTranslation(doc, "action", actionTranslation);

            } catch (SAXException | IOException e) {

                e.printStackTrace();

                // don't return to load as much as possible

            }

            // on the other hand, it's OK for one resource to override another

            this.menuTranslation.putAll(menuTranslation);

            this.itemTranslation.putAll(itemTranslation);

            this.actionTranslation.putAll(actionTranslation);

            translationLoaded = true;

        }

        return translationLoaded;

    }

    private static void loadTranslation(final Document doc, final String tagName, final Map<String, String> m) {

        final NodeList menuChildren = doc.getElementsByTagName(tagName);

        final int size = menuChildren.getLength();

        for (int i = 0; i < size; i++) {

            final Element element = (Element) menuChildren.item(i);

            final String id = element.getAttributeNode("id").getValue();

            final String label = element.getAttributeNode("label").getValue();

            if (m.containsKey(id)) {

                throw new IllegalStateException("Duplicate " + tagName + " translation entry for " + id + " (" + label + ")");

            }

            m.put(id, label);

        }

    }

}