/*

 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.

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

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.util.locale.provider;

import java.security.AccessController;

import java.text.spi.BreakIteratorProvider;

import java.text.spi.CollatorProvider;

import java.text.spi.DateFormatProvider;

import java.text.spi.DateFormatSymbolsProvider;

import java.text.spi.DecimalFormatSymbolsProvider;

import java.text.spi.NumberFormatProvider;

import java.util.ArrayList;

import java.util.List;

import java.util.Locale;

import java.util.ResourceBundle;

import java.util.Set;

import java.util.spi.CalendarDataProvider;

import java.util.spi.CalendarNameProvider;

import java.util.spi.CurrencyNameProvider;

import java.util.spi.LocaleNameProvider;

import java.util.spi.LocaleServiceProvider;

import java.util.spi.TimeZoneNameProvider;

import sun.util.cldr.CLDRLocaleProviderAdapter;

/**

 * The LocaleProviderAdapter abstract class.

 *

 * @author Naoto Sato

 * @author Masayoshi Okutsu

 */

public abstract class LocaleProviderAdapter {

    /**

     * Adapter type.

     */

    public static enum Type {

        JRE("sun.util.resources", "sun.text.resources"),

        CLDR("sun.util.resources.cldr", "sun.text.resources.cldr"),

        SPI,

        HOST,

        FALLBACK("sun.util.resources", "sun.text.resources");

        private final String UTIL_RESOURCES_PACKAGE;

        private final String TEXT_RESOURCES_PACKAGE;

        private Type() {

            this(null, null);

        }

        private Type(String util, String text) {

            UTIL_RESOURCES_PACKAGE = util;

            TEXT_RESOURCES_PACKAGE = text;

        }

        public String getUtilResourcesPackage() {

            return UTIL_RESOURCES_PACKAGE;

        }

        public String getTextResourcesPackage() {

            return TEXT_RESOURCES_PACKAGE;

        }

    }

    /**

     * LocaleProviderAdapter preference list. The default list is intended

     * to behave the same manner in JDK7.

     */

    private static Type[] adapterPreference = {

        Type.JRE,

        Type.SPI,

    };

    /**

     * JRE Locale Data Adapter instance

     */

    private static LocaleProviderAdapter jreLocaleProviderAdapter = new JRELocaleProviderAdapter();

    /**

     * SPI Locale Data Adapter instance

     */

    private static LocaleProviderAdapter spiLocaleProviderAdapter = new SPILocaleProviderAdapter();

    /**

     * CLDR Locale Data Adapter instance, if any.

     */

    private static LocaleProviderAdapter cldrLocaleProviderAdapter = null;

    /**

     * HOST Locale Data Adapter instance, if any.

     */

    private static LocaleProviderAdapter hostLocaleProviderAdapter = null;

    /**

     * FALLBACK Locale Data Adapter instance. It's basically the same with JRE, but only kicks

     * in for the root locale.

     */

    private static LocaleProviderAdapter fallbackLocaleProviderAdapter = null;

    static {

        String order = AccessController.doPrivileged(

                           new sun.security.action.GetPropertyAction("java.locale.providers"));

        // Override adapterPreference with the properties one

        if (order != null && order.length() != 0) {

            String[] types = order.split(",");

            List<Type> typeList = new ArrayList<>();

            for (String type : types) {

                try {

                    Type aType = Type.valueOf(type.trim().toUpperCase(Locale.ROOT));

                    // load adapter if necessary

                    switch (aType) {

                        case CLDR:

                            cldrLocaleProviderAdapter = new CLDRLocaleProviderAdapter();

                            break;

                        case HOST:

                            hostLocaleProviderAdapter = new HostLocaleProviderAdapter();

                            break;

                    }

                    typeList.add(aType);

                } catch (IllegalArgumentException | UnsupportedOperationException e) {

                    // could be caused by the user specifying wrong

                    // provider name or format in the system property

                    LocaleServiceProviderPool.config(LocaleProviderAdapter.class, e.toString());

                }

            }

            if (!typeList.isEmpty()) {

                if (!typeList.contains(Type.JRE)) {

                    // Append FALLBACK as the last resort.

                    fallbackLocaleProviderAdapter = new FallbackLocaleProviderAdapter();

                    typeList.add(Type.FALLBACK);

                }

                adapterPreference = typeList.toArray(new Type[0]);

            }

        }

    }

    /**

     * Returns the singleton instance for each adapter type

     */

    public static LocaleProviderAdapter forType(Type type) {

        switch (type) {

        case JRE:

            return jreLocaleProviderAdapter;

        case CLDR:

            return cldrLocaleProviderAdapter;

        case SPI:

            return spiLocaleProviderAdapter;

        case HOST:

            return hostLocaleProviderAdapter;

        case FALLBACK:

            return fallbackLocaleProviderAdapter;

        default:

            throw new InternalError("unknown locale data adapter type");

        }

    }

    public static LocaleProviderAdapter forJRE() {

        return jreLocaleProviderAdapter;

    }

    public static LocaleProviderAdapter getResourceBundleBased() {

        for (Type type : getAdapterPreference()) {

            if (type == Type.JRE || type == Type.CLDR || type == Type.FALLBACK) {

                return forType(type);

            }

        }

        // Shouldn't happen.

        throw new InternalError();

    }

    /**

     * Returns the preference order of LocaleProviderAdapter.Type

     */

    public static Type[] getAdapterPreference() {

        return adapterPreference;

    }

    /**

     * Returns a LocaleProviderAdapter for the given locale service provider that

     * best matches the given locale. This method returns the LocaleProviderAdapter

     * for JRE if none is found for the given locale.

     *

     * @param providerClass the class for the locale service provider

     * @param locale the desired locale.

     * @return a LocaleProviderAdapter

     */

    public static LocaleProviderAdapter getAdapter(Class<? extends LocaleServiceProvider> providerClass,

                                               Locale locale) {

        // Fast look-up for the given locale

        if (adapter != null) {

            return adapter;

        }

        // Try finding an adapter in the normal candidate locales path of the given locale.

        List<Locale> lookupLocales = ResourceBundle.Control.getControl(ResourceBundle.Control.FORMAT_DEFAULT)

                                        .getCandidateLocales("", locale);

        for (Locale loc : lookupLocales) {

            if (loc.equals(locale)) {

                // We've already done with this loc.

                continue;

            }

            adapter = findAdapter(providerClass, loc);

            if (adapter != null) {

                return adapter;

            }

        }

        // returns the adapter for FALLBACK as the last resort

        return fallbackLocaleProviderAdapter;

    }

    private static LocaleProviderAdapter findAdapter(Class<? extends LocaleServiceProvider> providerClass,

                                                 Locale locale) {

        for (Type type : getAdapterPreference()) {

            LocaleProviderAdapter adapter = forType(type);

            LocaleServiceProvider provider = adapter.getLocaleServiceProvider(providerClass);

            if (provider != null) {

                if (provider.isSupportedLocale(locale)) {

                    return adapter;

                }

            }

        }

        return null;

    }

    /**

     * A utility method for implementing the default LocaleServiceProvider.isSupportedLocale

     * for the JRE, CLDR, and FALLBACK adapters.

     */

    static boolean isSupportedLocale(Locale locale, LocaleProviderAdapter.Type type, Set<String> langtags) {

        assert type == Type.JRE || type == Type.CLDR || type == Type.FALLBACK;

        if (Locale.ROOT.equals(locale)) {

            return true;

        }

        if (type == Type.FALLBACK) {

            // no other locales except ROOT are supported for FALLBACK

            return false;

        }

        locale = locale.stripExtensions();

        if (langtags.contains(locale.toLanguageTag())) {

            return true;

        }

        if (type == Type.JRE) {

            String oldname = locale.toString().replace('_', '-');

            return langtags.contains(oldname);

        }

        return false;

    }

    public static Locale[] toLocaleArray(Set<String> tags) {

        Locale[] locs = new Locale[tags.size() + 1];

        int index = 0;

        locs[index++] = Locale.ROOT;

        for (String tag : tags) {

            switch (tag) {

            case "ja-JP-JP":

                locs[index++] = JRELocaleConstants.JA_JP_JP;

                break;

            case "th-TH-TH":

                locs[index++] = JRELocaleConstants.TH_TH_TH;

                break;

            default:

                locs[index++] = Locale.forLanguageTag(tag);

                break;

            }

        }

        return locs;

    }

    /**

     * Returns the type of this LocaleProviderAdapter

     */

    public abstract LocaleProviderAdapter.Type getAdapterType();

    /**

     * Getter method for Locale Service Providers.

     */

    public abstract <P extends LocaleServiceProvider> P getLocaleServiceProvider(Class<P> c);

    /**

     * Returns a BreakIteratorProvider for this LocaleProviderAdapter, or null if no

     * BreakIteratorProvider is available.

     *

     * @return a BreakIteratorProvider

     */

    public abstract BreakIteratorProvider getBreakIteratorProvider();

    /**

     * Returns a ollatorProvider for this LocaleProviderAdapter, or null if no

     * ollatorProvider is available.

     *

     * @return a ollatorProvider

     */

    public abstract CollatorProvider getCollatorProvider();

    /**

     * Returns a DateFormatProvider for this LocaleProviderAdapter, or null if no

     * DateFormatProvider is available.

     *

     * @return a DateFormatProvider

     */

    public abstract DateFormatProvider getDateFormatProvider();

    /**

     * Returns a DateFormatSymbolsProvider for this LocaleProviderAdapter, or null if no

     * DateFormatSymbolsProvider is available.

     *

     * @return a DateFormatSymbolsProvider

     */

    public abstract DateFormatSymbolsProvider getDateFormatSymbolsProvider();

    /**

     * Returns a DecimalFormatSymbolsProvider for this LocaleProviderAdapter, or null if no

     * DecimalFormatSymbolsProvider is available.

     *

     * @return a DecimalFormatSymbolsProvider

     */

    public abstract DecimalFormatSymbolsProvider getDecimalFormatSymbolsProvider();

    /**

     * Returns a NumberFormatProvider for this LocaleProviderAdapter, or null if no

     * NumberFormatProvider is available.

     *

     * @return a NumberFormatProvider

     */

    public abstract NumberFormatProvider getNumberFormatProvider();

    /*

     * Getter methods for java.util.spi.* providers

     */

    /**

     * Returns a CurrencyNameProvider for this LocaleProviderAdapter, or null if no

     * CurrencyNameProvider is available.

     *

     * @return a CurrencyNameProvider

     */

    public abstract CurrencyNameProvider getCurrencyNameProvider();

    /**

     * Returns a LocaleNameProvider for this LocaleProviderAdapter, or null if no

     * LocaleNameProvider is available.

     *

     * @return a LocaleNameProvider

     */

    public abstract LocaleNameProvider getLocaleNameProvider();

    /**

     * Returns a TimeZoneNameProvider for this LocaleProviderAdapter, or null if no

     * TimeZoneNameProvider is available.

     *

     * @return a TimeZoneNameProvider

     */

    public abstract TimeZoneNameProvider getTimeZoneNameProvider();

    /**

     * Returns a CalendarDataProvider for this LocaleProviderAdapter, or null if no

     * CalendarDataProvider is available.

     *

     * @return a CalendarDataProvider

     */

    public abstract CalendarDataProvider getCalendarDataProvider();

    /**

     * Returns a CalendarNameProvider for this LocaleProviderAdapter, or null if no

     * CalendarNameProvider is available.

     *

     * @return a CalendarNameProvider

     */

    public abstract CalendarNameProvider getCalendarNameProvider();

    public abstract LocaleResources getLocaleResources(Locale locale);

    public abstract Locale[] getAvailableLocales();

}